Bartonella henselae is a fastidious Gram-negative intracellular bacterium which can cause cat scratch disease, endocarditis in humans and animals as well as other complications, leading to acute or chronic infections. The current treatment for Bartonella infections is not very effective due to antibiotic resistance and also persistence. To develop better therapies for persistent and chronic Bartonella infections, in this study, with the help of SYBR Green I/PI viability assay, we performed a high-throughput screening of an essential oil library against stationary phase B. henselae. We successfully identified 32 essential oils that had high activity, including four essential oils extracted from Citrus plants, three from Origanum, three from Cinnamomum, two from Pelargonium and two from Melaleuca, as well as frankincense, ylang ylang, fir needle, mountain savory (winter), citronella, spearmint, elemi, vetiver, clove bud, allspice and cedarwood essential oils. The minimal inhibitory concentration (MIC) determination of these 32 top hits indicated they were not only active against stationary phase non-growing B. henselae but also had good activity against log phase growing B. henselae. The time-kill curve by drug exposure assay showed 13 active hits, including essential oils of oregano, cinnamon bark, mountain savory (winter), cinnamon leaf, geranium, clove bud, allspice, geranium bourbon, ylang ylang, citronella, elemi and vetiver, could eradicate all stationary phase B. henselae cells within 7 days at the concentration of 0.032% (v/v). Two active ingredients, carvacrol and cinnamaldehyde, of oregano and cinnamon bark essential oils, respectively, were shown to be very active against stationary phase B. henselae such that they were able to eradicate all the bacterial cells even at the concentration ≤ 0.01% (v/v). Our finding of active essential oils may help to develop more effective treatments for persistent Bartonella infections.

We ascertain the in vitro Benznidazole (BZN) and Nifurtimox (NFX) susceptibility pattern of epimastigotes, trypomastigotes, and amastigotes of 21 T. cruzi strains, from patients, reservoir and triatomine bugs of various geographic origin. Using this panel of isolates, we compute the Epidemiological cut off value (CO_wt). Then, the frequency of the susceptible phenotype (Wild type) towards BZN and nifurtimox (NFX) within this set of strains belonging to 3 discrete typing units (DTUs), TcI, TcII, and TcV was deduced. We have observed that the susceptibility status of individual T. cruzi isolates toward BZN and NFX is related to the genetic background and to underlying factors probably related to the individual life trait history of each strain. Analyzing drug susceptibility in this conceptual framework would offers the possibility to evidence a link between isolates expressing a low susceptibility level (not wild-type) as define by the CO_wt value and none-curative treatment. It will also permit to tract drug-resistant parasites in T. cruzi population.

Description of a novel bovine antimicrobial peptide and its antimicrobial spectrum. RNA isolation and RT-PCR were done from various tissues. DCD peptide was synthesized, and antimicrobial activity was analyzed. Bovine dermcidin gene contains five exons intermittent by 4 introns. Bovine DCD-mRNA was 398 bp with ORF 336 bp. Bovine DCD was expressed in skin and blood. Analysis of the amino acid compositions revealed that cysteine was repeated 6 times indicating the presence of 3 disulfide bonds that play role in the peptide stability. Staphylococcus epidermidis, Streptococcus bovis, and Enterococcus faecalis were affected by Bovine DCD peptide. Highest antimicrobial effect was at 50 and 100 µg/ml. The effect on Escherichia coli and Candida albicans was slightly low. In all bacteria, Bovine DCD peptide activity did not affect by varying pH values, but in Staphylococcus aureus, the activity was affected greatly at pH 4.5 and 5.5. The optimum salt concentrations were 100 and 50 mM NaCl with all bacterial strains and E. coli, respectively. In case of C. albicans, the antimicrobial activity of Bovine DCD peptide decreased with increasing the pH value regardless the NaCl concentration. The pH 6.5 of the sweat buffer was the optimum for the Bovine DCD peptide activity.

Antimicrobial stewardship efforts are an emphasis among many institutions around the world to combat inappropriate antimicrobial utilization, rising healthcare costs and emerging antimicrobial resistance. Implementation of new innovative strategies may be challenging for many institutions with limited or constrained resources. Using proven effective methods as evidenced by other institutions in the peer-reviewed literature may offer an opportunity to evaluate institution-specific practices, which may be implemented locally. A structured examination and survey of the peer-reviewed, stewardship literature by an expert group of clinicians, scholars and educators determined the most influential publications from 2016. Herein, the top thirteen manuscripts are reviewed to aid clinicians identify potential stewardship opportunities and serve as an educational tool for trainees and others.

The antioxidant, antimicrobial, antiproliferative, and enzyme inhibitory properties of five extracts from aerial parts of Salvia pachyphylla were examined to assess the prospective of this plant as a source of natural products with therapeutic potential. Those properties were analyzed performing a set of standard assays. The extract obtained with dichloromethane showed the most variety of components, as yielded promising results in all completed assays. Furthermore, the extract obtained with ethyl acetate exhibited that greatest antioxidant activity as well as the best xanthine oxidase inhibitory activity. Remarkably, both extracts obtained with n-hexane or dichloromethane revealed significant antimicrobial activity against the Gram-positive bacteria; also, they showed greater antiproliferative activity against three representative cell lines of the most common types of cancers in women worldwide, and against a cell line that exemplifies cancers that typically develop drug resistance. Despite that other extracts were less active, such as the methanolic or aqueous, their results are promising for the isolation and identification of novel bioactive molecules.

The antibiotic or antimicrobial resistance is rapidly spreading in microbes relevant to human health. Two visible major contributory factors have been the indiscriminate overuse of antimicrobials for preventing diseases in human and to enhance the productivity in agriculture sector. To mitigate the potential threat posed by post-antibiotic era, the global health stakeholders have been making extra efforts at a war footing to formulate and implement global and national plans of action. In the current article, an endeavour is made to provide a perspective to look beyond the current focus on just use of the antimicrobials. Attention has been drawn towards various obvious and not-so-obvious self-preservation infection-prevention practices in vogue from the pre-antibiotic era whose usage has been on decline in the antibiotic era for various reasons. Particularly, the practices with a clear potential to effectively decrease the spread of pathogens through contact, curtail the evolution and dissemination of the antimicrobial resistance in local environment and its introduction into the global community, should be Identified and strengthened to make them part of comprehensive hygiene and quarantine practices. Broadly, the suggestions pertaining to the personal and community hygiene including bereavement practices, isolation and quarantine of suspected pathogen carriers, and water and environment security have been made to invoke a constructive debate and discussion among various stakeholders for their evaluation and implementation to effectively delay the development of antimicrobial resistance wherever possible and disrupt its spread to pathogens.

Biofilm-associated bacterial infections are the major reason for treatment failure in many diseases including burn trauma infections. Uncontrolled inflammation induced by bacteria leads to materiality, tissue damage and chronic diseases. Specialized proresolving mediators (SPMs), including maresin-like lipid mediators (MarLs), are enzymatically biosynthesized from omega-3 essential long-chain polyunsaturated fatty acids, especially docosahexaenoic acid (DHA) by macrophages and other leukocytes. SPMs exhibit strong inflammation-resolving activities, especially inflammation provoked by bacterial infection. In this study, we explored the potential direct inhibitory activities of three MarLs on gram-positive (Staphylococcus aureus) and gram-negative (Pseudomonas aeruginosa and Escherichia coli) bacteria in their biofilms that are leading bacteria in burn trauma related infections. We also examined the effects of MarLs on the bactericidal activities of a typical broad-spectrum antibiotics carbenicillin on these bacteria in their preformed biofilms. The results revealed that MarLs combined with carbenicillin can inhibit the survival of gram-positive and gram-negative bacteria in their biofilms although MarLs alone did not exhibit bactericidal activity. Thus, our findings suggest that the combination of MarLs and carbenicillin can lower the antibiotic requirements to kill the bacteria in preformed biofilms.

The present work was aimed at the chemical characterization and antimicrobial activity of some extracts of aerial parts (essential oils from leaves and inflorescences, and resins from inflorescences) of two legal hemp (Cannabis sativa) varieties, Tisza and Kompolti, grown in Sardinia. Chemical characterization was carried out by gas chromatography (GC) and gas chromatography-mass spectrometry (GC-MS) techniques. The antimicrobial activity of these extracts against a panel of microorganisms was also determined via minimum inhibitory concentration (M.I.C.) determination. While the results showed a minor or negligible antimicrobial activity of the extracts against Gram+ and Candida strains, a good antibacterial activity (especially of resins) was recorded against S. aureus; no substantial differences were detected between of the chemical compositions of the two Cannabis varieties.

Natural host defensins, also sometimes termed antimicrobial peptides, are evolutionarily conserved. They have been studied as antimicrobials, but some pharmaceutical properties, undesirable for clinical use, led to the development of synthetic molecules with constructed peptide arrangements and/or peptides not found in nature. The leading development currently is synthetic small molecule nonpeptide mimetics, whose physical properties capture the characteristics of the natural molecules, and share their biological attributes. We studied brilacidin, an arylamide of this type, for its activity in vitro against fungi (40 clinical isolates, 20 species) that the World Health Organization has highlighted as problem human pathogens. We find antifungal activity at low concentrations for many pathogens, which indicates further screening for activity, particularly in vivo, is justified to evaluate this compound, and other mimetics, as attractive leads for development of effective antifungal agents.

Acne vulgaris is a prevalent dermatological disorder that impacts the quality of life for millions of people around the world. The multifactorial nature of this disorder requires innovative and effective treatment strategies. Over time, there has been a growing interest regarding the use of natural topical therapies, with cannabinoids emerging as a promising group of compounds for investiga-tion. In the context of acne treatment, cannabinoids are of particular interest due to their anti-acne properties, namely, lipostatic, anti-inflammatory, antiproliferative, and antimicrobial activities. Among these bioactive compounds, cannabidiol stands out as a notable derivative, exhibiting a promising spectrum of therapeutic actions. Pre-clinical and clinical studies have proven its ability to modulate sebum production, reduce inflammation, and inhibit bacterial proliferation - all of which are critical components in the pathogenesis of this dermatosis. This review provides a comprehen-sive overview of cannabinoids' potential as a novel and holistic approach to acne vulgaris treatment and summarizes recent developments in this area.

Introduction Our aim was to determine the impact of antimicrobial stewardship tools (AST) and COVID-19 pandemic on antibiotic consumption (AC). Methods We used the national software Consores to determine AC in DDD / 1000 days of hospitalization from 2017 to 2022 in voluntary private hospitals in France. The AST considered were 1/ internal guidelines 2/ list of antibiotics with restricted access 3/ presence of an antibiotic referent or 4/ an ID specialist 5/ proof of annual meeting on antimicrobial resistance. Institutions with dedicated units for COVID-19 patients were specified. Results In 30 institutions total AC varied from (means) 390 to 405 DDD/1000 DH from 2017 to 2022. Fluoroquinolones and amoxicillin / clavulanate consumption decreased from 50 to 36 (p = 0.003) and from 112 to 77 (p = 0.025) respectively, but consumption of piperacillin / tazobactam increased from 9 to 21 (p < 0.001). Over the study period, 10 institutions with ≤ 2 AST had lower AC compared to 20 institutions with ≥ 3 AST (p < 0.01). COVID-19 units opened in 10 institutions were associated with a trend toward higher macrolide consumption from 15 to 25 from 2017 to 2020 (p = 0.065) and with an acceleration of piperacillin / tazobactam consumption from 2020 to 2022 (p ≤ 0.003). Conclusion Antibiotic consumption in 30 private hospitals in France was inversely related to the number of AST. The COVID-19 pandemic was associated with limited impact on AC but special attention should be paid on piperacillin / tazobactam consumption.

Diarrhea-related mortality remains an important public health concern, particularly in developing countries, and has become difficult to treat because of antibacterial resistance. The development of synergistic antimicrobial agents appears to be a promising alternative treatment against diar-rheal infections. In this study, the combined effect of tetracycline together with either nitroxoline, sanguinarine, or zinc pyrithione (representing various classes of alkaloid-related compounds) was evaluated in vitro against selected diarrheagenic bacteria (Enterococcus faecalis, Escherichia coli, Listeria monocytogenes, Shigella flexneri, Vibrio parahaemolyticus, and Yersinia enterocolitica). The chequerboard method in 96-well microtiter plates was used to determine the sum of the fractional inhibitory concentration indices (FICIs). Three independent experiments were performed per combination, each in triplicate. It was observed that the combinations of tetracycline with either nitroxoline, sanguinarine, or zinc pyrithione produced synergistic effects against most of the pathogenic bacteria tested, with FICI values ranging from 0.086 to 0.5. Tetracycline-nitroxoline combinations produced the greatest synergistic action against S. flexneri at a FICI value of 0.086. Combinations of the agents tested in this study can thus be used for the development of new anti-diarrheal medications. However, studies focusing on their in vivo anti-diarrheal activity and safety are required before any consideration for utilization in human medicine.

The ESKAPE pathogens are public health concerns worldwide, defining the present major antibiotic resistance issues: E. faecium vancomycin-R, S. aureus methicillin-R, Ps. Aeruginosa and A. baumannii carbapenem-R, resistance to 3rd generation cephalosporins of Kl. pneumoniae and Enterobacter spp. Covid-19 pandemic disturbed the health care usual procedures, contributing to the spread of antibiotic-resistant bacteria. The present study retrospectively assessed the prevalence and antimicrobial resistance (AMR) profile of ESKAPE microorganisms during 2020-2022 in a multidisciplinary emergency hospital from Romania, based on microbiological reports. The AMR issues mainly interest the urology department. ESKAPE group accounts for 33.5% of the total bacterial isolated. The specific AMR of ESKAPE pathogens cumulates 30.9%, while antimicrobial multidrug resistance characterizes 21% from all ESKAPE strains. Kl. Pneumoniae, followed by S. aureus, and Ps. aeruginosa are the main hospital problems concerning the ESKAPE surveillance. The directions of the near future antibiotic stewardship program focus to revise the clinical protocols for diagnostic and treatment in each department, to intensify the bacteriological samples collection, to improve the microbiological diagnostic techniques for AMR identification, to continue the epidemiological current actions of surveillance, control, and education.

Antimicrobial peptides (AMPs) are essential components of the innate immune system, present across a spectrum of organisms. Their versatility lies in their ability to effectively inhibit a wide range of pathogens including bacteria, fungi, parasites, and viruses. As the challenge of antibiotic resistance escalates and concerns surrounding antibiotic use grow, AMPs have emerged as promising alternatives. Their applications span diverse domains such as medicine, agriculture, food production, animal husbandry, and aquaculture, primarily due to their efficacy against resistant pathogens, signifying their crucial role in combating infections. Beyond their antimicrobial properties, research illuminates their intricate involvement in the immune response network. These peptides impact crucial processes including cytokine release, chemotaxis, wound healing, angiogenesis and the activation of the adaptive immune system. This comprehensive review delves into the multifaceted realm of AMPs, encompassing their classification, varied applications across industries and notably, their significance in diverse disease conditions like infections, skin diseases, cancer, oral diseases, lung diseases and cardiovascular ailments. Special attention is directed towards current advancements in clinical applications of peptide-based therapeutics, offering invaluable insights into their potential future integration within clinical settings.

Cissus populnea Guill. & Perr. (Vitaceae) is used in traditional medicine to treat microbial infec-tions, venereal diseases, and infertility, among others. The aim of the research is to isolate and characterize the antimicrobial constituent(s) from the stem of C. populnea. The n-butanol fraction of C. populnea being most active was subjected to silica gel column chromatography which led to the isolation of a white solid and white crystalline substances coded compounds C1 and C4C5, respectively. Spectral analysis (1D & 2D-NMR) of the isolated compounds and comparison with literature data indicated C1 to be Bis-(2-ethyloctyl)-phthalate and C4C5 to be a mixture of stig-masterol and β-sitosterol; C4C5 exhibited zone of inhibition ranging from 24 – 29 mm against the test organisms with Candida albicans being the most sensitive organism while Trichophyton rubrum was the least sensitive organism. The standard drugs, Ciprofloxacin had 27 – 37 mm while Flu-conazole and Fulcin exhibited zone of inhibition ranging from 34 mm and 29 – 32 mm, respec-tively. The MIC and MBC/MFC values for C4C5 ranges from 12.5 – 25.0 µg/cm3 and 25.0 – 50.0 µg/cm3 against MRSA, S. aureus, E. coli, C. albicans, T. rubrum, and T. mentagrophyte, respectively. In conclusion, three bioactive compounds were identified for the first time from the stem of C. populnea

Plants have been used in alternative medicine for centuries in the treatment of many diseases with the metabolites they contain. The goal of this work was to investigate the phenolic profile, antioxidant capacity and biological activity of I. helenium subsp. pseudohelenium extracts. Phe-nolic (HPLC) substances in leaf ethanol (L-EtOH), leaf pure water (L-PW), root ethanol (R-EtOH), and root pure water (R-PW) extracts of Inula helenium subsp. pseudohelenium plant were investi-gated. Also, in vitro the antimicrobial (hollow agar), antioxidant (DPPH, ABTS.+, FRAP, CU-PRAC), antiproliferative (MTT assay against HT-29, MCF-7 and L-929), and DNA (Agarose gel electrophoresis) protective activities of the samples were examined. Although gallic acid was not detected in the extracts, the presence of curcumin was detected only in EtOH extracts. L-EtOH exhibited the best antimicrobial activity. According to the antioxidant results, it was found that the L-EtOH extract had an activity profile close to the standard antioxidants in general. It was also found that the L-EtOH extract stabilized the DNA by disrupting the scavenging effect of H2O2+DMSO. According to the antiproliferative activity results, EtOH extracts exhibited the strongest effect, especially against MCF7. When evaluated in general terms, it was found that L-EtOH extract showed better activity than other extracts. It is important to conduct more in vivo and in vitro studies after isolating the active components of extracts e.g. L-EtOH, which have good effects in terms of biological activity.

Antimicrobial photodynamic therapy (aPDT) used to sterilize carious dentin may irritate the pulp tissues because of tissue-penetrating laser and singlet oxygen generation. This study aimed to assess the effects of aPDT on rat pulp tissues. A cavity formed in a rat maxillary first molar was treated with aPDT. The combined photosensitizer and laser irradiation conditions in the aPDT groups were as follows: methylene blue and 100 mW for 60 s, brilliant blue (BB) and 100 mW for 60 s, BB and 50 mW for 120 s, and BB and 200 mW for 30 s. Each cavity was treated with an all-in-one adhesive and filled with flowable resin. aPDT was not applied for the control. In each group, the rats were sacrificed on postoperative days 1 and 14, and thin sections of the treated teeth were prepared. Pulp tissue disorganization (PTD), inflammatory cell infiltration (ICI), and tertiary dentin formation (TDF) were evaluated. At 1 day evaluation, there were significant differences between the aPDT group and controls with respect to PTD and ICI. 14 days later, almost all specimens showed tertiary dentin formation. aPDT caused temporarily reversible injury to the rat dental pulp, which healed with tertiary dentin formation.

Background: Advances in additive manufacturing and the development of antimicrobial biopolymers facilitate the production of critical medical devices with strong and safe biocidal properties. The purpose of this study was to assess the antimicrobial efficacy, safety, and longevity of a polylactic acid-based biopolymer supplemented with a copper-based composite additive. Methods: An antimicrobial polylactic acid-based biopolymer was tested against several inoculants including Staphylococcus Aureus, MRSA, E. coli, Listeria, HCoV-229E (a SARS-CoV-2 surrogate), and HIV-1. Material safety was evaluated according to international testing standards for in vitro cytotoxicity. Results: The main findings of the present investigation showed a strong and long-lasting biocidal effect of a polylactic acid-based biopolymer embedded with a copper-based composite additive against Staphylococcus Aureus, MRSA, E. coli, Listeria, HCoV-229E (a SARS-CoV-2 surrogate), and HIV-1. Furthermore, the cytotoxicity and safety assessment of the antimicrobial biopolymer was found to be “non-toxic” and safe for human skin contact. Conclusions: The present investigation showed that the antimicrobial biopolymer exhibits strong and long-lasting biocidal properties against an array of viral and bacterial inoculants.

The recently reported microbial natural product N-benzoyl-tryptophane (1) along with twenty-two diverse known bioactive compounds were isolated from the marine Aspergillus terreus LGO13 after its re-cultivation using liquid culture fermentation. Structures of the isolated compounds were established on the basis of HR-ESIMS 1D/2D NMR spectroscopy, and comparison with literature data. The antimicrobial, cytotoxicity, and antiviral activities of the microbial extract and the obtained compounds were investigated using a set of microorganisms, cervix carcinoma KB-3-1, non-small cell lung cancer (NSCLC) A549, and coronavirus (SARS-CoV-2), respectively. Molecular docking (MD) simulation was employed to explore the theoretical targets of the isolated metabolites as anti-SARS-CoV-2 agents. Chaetominine (2) seemed to be a potential candidate against papain-like protease (PLpro), one of the viral proteins being aimed by recent research as a possible target of anti-covid agents. Inspired by the MD results, we accordingly assessed the antiviral efficacy of chaetominine (2), fumitremorgin C (6), and azaspirofuran A (9) against SARS-CoV-2. Fumitremorgin C (6) showed a high selectivity index (SI = 20.3), while chaetominine (2) and azaspirofuran A (9) showed moderate selectivity index (SI = 6.6 and 3.2, respectively). These results showed a promising antiviral activity of Fumitremorgin C against SARS-CoV-2 virus.

Surfactants are amphiphilic molecules and one of the most versatile products of the chemical industry. They can be absorbed at the air-water interface and can align themselves so that the hydrophobic part is in the air while the hydrophilic part is in water. This alignment lowers the surface or interfacial tension. Gemini surfactants are a modern variety of surfactants with unique properties and a very wide range of potential applications. Hexamethylene-1,6-bis(N-dodecyl-N,N-dimethylammonium bromide) is one such representative compound that is a better alternative to a single analogue. It shows excellent surface, antimicrobial, and anticorrosion properties. With a highly efficient synthetic method and a good ecological profile, it is a potential candidate for numerous applications, including biomedical applications.

Bee products have a millennial tradition in human use due to their numerous heal-ing properties. The paper presents the chemical characterization, antioxidant, anti-microbial and anti-inflammatory potential of royal jelly, apilarnil and propolis. These were obtained in the Banat area, Romania, in 2022. Royal jelly and apilarnil were analyzed in pure and lyophilized form and propolis in pure form and tincture. The percentage of moisture, dry matter, pH, acidity, content of impurities, sugars, proteins, ash, macro and micro minerals, total amino acids, polyphenols and flavo-noids were studied. The samples analyzed by us have a very well developed antiox-idant and according to the analysis of the mineral content of beekeeping products, an increased variability of macro and microminerals was determined, but also the lack of Pb in their composition. The flavonoid content of the samples was between 2.61519 mg QE/g sample for commercial pure apilarnil and 279.56115 mg QE/g sample for propolis harvested in 2021, and that of polyphenols between 0.63507 mg QE/g sample for natural royal jelly and 42.82186 mg QE/g sample in propolis with harvest in 2021. Propolis acts as a good antimicrobial and antiinflammatory agent, a fact that deserves to be researched in detail and exploited as a product with an ap-itherapeutic role for various microbial and inflammatory conditions.

In this work we present a study of impact of textile materials used in health care facilities on microbial colonization of textile surfaces. Polypropylene yarns doped with silver phosphate glass and zinc pyrithione were prepared and used for production of bed sheets and clothing for healthcare personnel. Subsequently measurements of airborne particles and viable microorganisms on given textiles were conducted in a private surgery clinic during 3 weeks comparing the counts of viable microorganisms before and after replacing of staff clothing and bedding on examination and surgical bed with said polypropylene cloth. In this study a significant reduction of viable airborne fungi and viable microorganisms on monitored textiles was observed by multiple methods.

Prevalence of antimicrobial-resistant bacteria has become a major challenge worldwide. Methicillin-resistant Staphylococcus aureus (MRSA)—a leading cause of infections—forms biofilms on polymeric medical devices and implants, increasing their resistance to antibiotics. Antibiotic administration before biofilm formation is crucial. Raman spectroscopy was used to assess MRSA biofilm development on solid culture media from 0 to 48 h. Biofilm formation was monitored by measuring DNA/RNA-associated Raman peaks and protein/lipid-associated peaks. The search for an antimicrobial agent against MRSA biofilm revealed that Eugenol was a promising candidate as it showed significant potential for breaking down the biofilm. Eugenol was applied at different times to test the optimal time for inhibiting MRSA biofilms, and the Raman spectrum showed that the first 5 h of biofilm formation was the most antibiotic-sensitive time. This study investigated the performance of Raman spectroscopy coupled with Principal Component Analysis (PCA) to identify planktonic bacteria from biofilm conglomerates. Raman analysis, microscopic observation, and quantification of the biofilm growth curve indicated early adhesion from 5 to 10 h of incubation time. Therefore, Raman spectroscopy can help in monitoring biofilm formation on a solid culture medium and performing rapid antibiofilm assessments with new antibiotics during the early stages of the procedure.

Chenodeoxycholic acid (CA) is a naturally occurring bile acid that is produced in the liver from cholesterol. Three CA complexes using Zn(II), Mg(II), and Ca(II) ions were synthesized to examine the chelation tendencies of CA towards these metal ions. The complexation reaction of CA with the metal ions under investigation was conducted with a 1:1 molar ratio (CA to metal) at 60-70°C in natural media (pH 7-8), which consisted of a binary solvent of MeOH and H2O (1:1). The resulting CA complexes were characterized using analytical data (metal, H, C, and Cl, analysis) and spectral data (UV-visible, FT-IR, and 1H NMR) to elucidate the complexes’ structures. The results suggested that CA in anion form utilized oxygen atoms of the carboxylate group (-COO−) to capture Zn(II), Mg(II), and Ca(II) ions. This produced complexes with the general compositions of [Zn(CA)(H2O)Cl], [Mg(CA)(H2O)Cl]H2O, and [Ca(CA)(H2O)Cl]2H2O, respectively. The Kirby-Bauer disc diffusion assay was then used to explore the bioactivity of the CA complexes toward three fungal species, three Gram-positive bacteria, and two Gram-negative bacteria. The Ca(II) and Mg(II) complexes exhibited marked inhibitory effects on the cell growth of the fungal species Aspergillus niger with potency equal to 127% and 116% of the activity of the positive control, respectively. The Zn(II) and Ca(II) complexes strongly inhibited the growth of Penicillium sp., while the Zn(II) and Mg(II) complexes showed strong growth inhibition towards the Gram-negative species Pseudomonas aeruginosa.

The chemical reaction between the quinolone antibiotic oxolinic acid (OA) and Fe(III), Zn(II), Ca(II), and Mg(II) ions results in the formation of metal-based complexes with the following formulas: [Fe(OA)(H2O)2Cl2]2H2O, [Zn(OA)(H2O)Cl]2H2O, [Ca(OA)(H2O)Cl], and [Mg(OA)(H2O)Cl]. We used analytical (C, N, H, Cl, metal analysis) and spectral (FT-IR, 1H NMR, UV-visible) data to structurally characterize the synthesized metal-based complexes of the OA molecule. We found that the OA molecule utilizes the two oxygen atoms of the carboxylate group and the pyridone C=O group to bind the investigated metal ions. The morphological properties of the synthesized OA complexes were assessed using X-ray powder diffractometry (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The biological properties, specifically antibacterial and antifungal activity, of the synthesized complexes were evaluated in vitro using the Kirby-Bauer disc diffusion protocol with five bacterial and three fungal strains. The complex containing Ca(II) ions exhibited remarkable antibacterial and antifungal activity against all tested microbial strains, surpassing or equaling the potency of the standard drugs (streptomycin for antibacterial assays and ketoconazole for antifungal assays).

Background: The AWaRe tool was set up by the World Health Organization (WHO) to promote the rational use of antimicrobials. Indeed, this tool classifies antibiotics into four groups, Access, Watch, Reserve and not-recommended antibiotics. In Republic Democratic of Congo, data on antibiotic dispensing (prescribing) by health professionals according to the AWaRe classification are scarce. In this research work, we aimed to explore antibiotic dispensing pattern from health professionals according to the WHO AWaRe classification to strengthen the national antimicrobial resistance plan. Methods: For this purpose, a survey was conducted from July to December 2022 in the district of Tshangu in Kinshasa. From randomly selected drugstores, drug-sellers were interviewed and randomly selected customers attending those drugstores were included in the study for medical prescriptions collection. The prescribed antibiotics were classified into the Access, Watch, Reserve and not recommended antibiotics group and by antibiotics number by prescription among pharmacies surveyed. Results: Of 400 medical prescriptions collected, 301 (75.25%) contained antibiotics. Of 301 prescriptions containing antibiotics, 164 (164/301; 54.5%) contained one antibiotic, 117 (117/301; 38.9%) two antibiotics, 15 (15/301; 5%) three antibiotics and 5 (5/301; 1.6%) 4 antibiotics. Out of the total of 463 antibiotics prescribed, 169 (169/463; 36.5%) were from the Access group, 200 (200/463; 43.2%) from the Watch group and 94 (94/463; 20.3%) from not recommended antibiotics group, respectively. Based on the anatomical, therapeutic and chemical (ATC) classification, it can be seen that third generation cephalosporins contained 34.33% of the prescribed antibiotics, followed by penicillins 17.17%, macrolides 7.63%, aminoglycosides 7. 36% and Imidazoles 7.36%, thus accounting approximately for 74% of the classes of antibiotics prescribed. Of the 463 antibiotics prescribed, the most frequently prescribed antibiotics were Ceftriaxone (21.38%), Amoxicillin (11.01%), Gentamycin (5.61%), Amoxicillin-clavulanic acid (5 .61%), Azithromycin (4.97%) and Metronidazole (4.75%), thus accounting for approximately 54% of all antibiotics prescribed. Conclusion: These results highlight the importance of strict implementation of the national plan to combat antimicrobial resistance and the need to train health workers in the correct application of the WHO AWaRe classification.

The rhizosphere is a rich source of actinomycetes which can produce several potential biologically-active secondary metabolites. The principal goals for this research are to extract, purify and characterize the bioactive secondary metabolites produced by three different strains of actinomycetes isolated from the rhizosphere of rosemary, black locust and olive. The plant growth-promoting effect (PGPE) of the studied strains of actinomycetes on Ocimum basilicum L. (basil) and disease-control effect on necrotic stem lesions of “black leg” caused by Fusarium tabacinum on basil, were in silico evaluated. The cell-free culture filtrates from the studied actinomycetes isolates were evaluated in vitro for their antimicrobial activity against some common phytopathogens. The secondary metabolites obtained from the cell-free culture filtrates have been chemically characterized using high‐resolution electrospray ionization of liquid-chromatography/mass-spectrometric detection (ESI-(HR)Orbitrap-MS). Results of in silico trial showed that all studied isolates demonstrated PGPE on basil seedlings improving some Eco-physiological characteristics and reduced the disease incidence of F. tabacinum. The extracted metabolites from the studied actinomycetes demonstrated antimicrobial activity in Petri-plates assay. The chemical analysis revealed the presence of totally 20 different components. This research emphasizes how valuable the examined isolates are for producing bioactive compounds, indicating their putative antimicrobial activity and their potential employment as fungal-biocontrol agents. In particular, the obtained results revealed the possibility of green-synthesis of some important secondary metabolites such as N-Acetyl-L-histidinol, Rhizocticin A and Eponemycin from actinomycetes. The bioactive metabolites may be successively used to develop novel bio-formulations for both crop protection and/or PGPE.

The Chromogranin A (CgA)-derived peptide Catestatin (CST: hCgA352-372) is highly conserved (>90% in 90% species) in mammalian species. The highest-evolved primates show 58.8% similarity with the lowest-evolved monotremes. CST was initially identified as a physiological brake in catecholamine secretion by inhibiting nicotinic-cholinergic signaling. CST also inhibits desensitization of catecholamine secretion, indicating that CST can act both as a cholinergic antagonist (short-term) and as a cholinergic agonist (long-term). The long-term effect sustains catecholamine secretion during stressful situations. CST is now established as a pleiotropic hormone: it affects the cardiovascular system by lowering blood pressure and cardiac contractility, enhancing baroreflex sensitivity, increasing heart rate variability, and promoting angiogenesis; and it increases insulin sensitivity by reducing inflammation, inhibiting hepatic glucose production, attenuating endoplasmic reticulum stress, and inducing glycogen production. The present review will highlight the important direct and indirect effects of CST, CST1-15 (aka cateslytin), D-CST1-15 (where L-amino acids were changed to D-amino acids), and human variants of CST (Gly364Ser-CST and Pro370Leu-CST) on microbial growth inhibition and their potential as therapy for antibiotic-resistant pathogenic microbes.

Cream cheese presents a favorable environment for the growth of pathogenic and spoilage microorganisms. The antimicrobial and antioxidant effects of plant extracts are well known, but their use is limited because they affect the physicochemical and sensory characteristics of products. Encapsulation presents an option to limit or prevent these changes. The paper presents the composition of individual polyphenols (HPLC–DAD-ESI-MS) from basil extracts (BE) with significant antioxidant activity (644.75±21.37 mM Trolox/g DW) and inhibitory effect against strains of Staphylococcus aureus, Geobacillus stearothermophilus, Bacillus cereus, Candida albicans, Enterococcus faecalis, Escherichia coli, and Salmonella Abony. The basil extract was encapsulated in sodium alginate (Alg) using the drop technique. The encapsulation efficiency of microencapsulated basil extract (MBE) was 78.59±0.01%. SEM and FTIR analyzes demonstrated the existence of weak physical interactions between the components. In the optimal concentration range of 0.6-0.9% MBE determined the inhibition of the post-fermentation process and the improvement of the degree of water retention. This led to the improvement of the textural parameters of the cream cheese, contributing to the extension of the shelf life of the product by 7 days. The influence of storage period and MBE concentration on texture parameters, pH and sensory analysis (overall acceptability) were evaluated by mutual information analysis.

Antimicrobial peptides (AMPs) are a promising alternative to antibiotics to combat drug resistance in pathogenic bacteria. However, the development of AMPs with high potency and specificity remains a challenge, and new tools to evaluate antimicrobial activity are needed to accelerate the discovery process. As a step toward direct prediction of the experimental minimum inhibitory concentration (MIC) of AMPs, we proposed MBC-Attention, a combination of a multi-branch CNN architecture and attention mechanism. Using a curated dataset of 3929 AMP against Escherichia coli, the optimal MBC-Attention model achieved an average Pearson correlation coefficient of 0.775 and an RMSE of 0.533 (log μM) in three independent tests of 393 sequences each. This results in a 5–12% improvement in PCC and 7–13% improvement in RMSE compared with RF and SVM models. Ablation studies confirmed that both attention mechanisms contributed to performance improvement.

Background: Bacterial infections constantly have a large impact on public health, because of increased rates of resistance and reduced frequency of development of novel antibiotics. The utility of conventional antibiotics for treating bacterial infections has become increasingly challenging. The aim of the study was to assess the antibacterial effect of β -Lapachone, a novel synthetic compound. Methods: The antibacterial activity of the β -Lapachone compound was examined against laboratory strains by agar well diffusion method, minimal inhibitory concentration (MICs), and minimal bactericidal concentration (MBCs). Growth kinetics inhibition in presence of β -Lapachone on Staphylococcus aureus, Staphylococcus epidermidis and Pseudomonas aeruginosa (ATCC 27853) was assessed by MABA. Crystal violet blue assay was used for biofilm inhibition assays, biofilm eradication assay and for molecular modeling PyMOL was used. Results: β -Lapachone exhibited potent antimicrobial activity against laboratory strains of bacteria with MIC of 0.2 mM for S. saprophyticus and Staphylococcus aureus, and 0.04 mM for Staphylococcus epidermidis and Pseudomonas aeruginosa ATCC 27853. The inhibition of catalase enzyme was found to be the cause for its antibacterial activity. Molecular modeling predicted the binding of β -Lap at active site and heme binding site of catalase, KatA. The activity of some commercial antibiotics was enhanced in association with β -Lap. In addition, β -Lap inhibited the biofilm formation and eradicated the already formed and ultra-mature biofilms of aforesaid bacterial strains.

Urinary peptides are the products of systemic protein turn over which are excreted out of the body and hence can serve as an important biomarker for various pathophysiology. These peptides in other species of bovine have been reported to possess several bioactive properties. To investigate the potential of urinary peptides we generated a peptidome profile from the urine of Murrah Buffaloes (n=10). Urine samples were processed using &lt;10 kDa MWCO filter, filtrate obtained was used for peptide extraction using Solid Phase Extraction (SPE). Eluate, obtained after SPE was extracted using ethyl acetate and the peptide-containing aqueous phase was collected. We extensively assessed the antimicrobial properties of the urinary aqueous phase. The nLC-MS/MS of the aqueous phase from 10 animals resulted in the identification of 8165 peptides originating from 6041 parent proteins. 76 Proteases responsible for the release of these sequences from precursor proteins were also identified. We further analyzed these peptide sequences to identify bioactive peptides and classify them into anti-cancerous, anti-hypertensive, anti-microbial, and anti-inflammatory groups with a special emphasis on antimicrobial properties. With this in mind, we simultaneously conducted experiments to evaluate antimicrobial properties of urinary aqueous extract on three pathogenic bacterial strains S. aureus, E. coli, &amp; S. agalactiae.

Antimicrobial resistance (AMR) due to community carriage of antibiotic-resistant bacteria is highly prevalent in the WHO South-East Asia region. One of the major reasons is the misuse of antibiotics in animal farming practices and at community level, which threatens both human and animal health. However, this multifaceted One Health (OH) problem of antibiotic use (ABU) in poultry farms and respective farmers is not well studied in countries like Pakistan. Therefore, we conducted n OH cross-sectional study in rural Punjab to explore the current practices of ABU in poultry and poultry farmers, associated factors, their healthcare-seeking behaviour and biosecurity practices. We found all the participating farmers using antibiotics for poultry, 60% of which were Colistin sulphate and Amoxicillin trihydrate. The significant consumption of antibiotics in poultry farms (60%) and poultry farmers (50%) was without prescription. Most of the farms (85%) had no wastewater drainage system, causing direct shedding of poultry waste and antibiotic residue in the surrounding environment. Lack of farmers’ education, professional farm training and duration of farming experience were the significantly associated factors with ABU and knowledge of AMR. Our study implies the necessity of an integrated OH-AMR policy with the inclusion of farmers’ education, mass awareness, and strict antibiotic usage guidelines.

Multicomponent reactions (MCR) have been used to synthesis a wide range of analogs from several classes of heterocyclic compounds, with multifaceted medicinal uses. The synthesis of highly functionalized molecules in a single pot is a unique property of MCR, allowing researchers to quickly assemble libraries of compounds of biological interest and uncover novel leads as possible therapeutic agents. Isocyanide-based multicomponent reactions have proven to be extremely effective at swiftly specifying members of compound libraries, particularly in discovery of drug . The understanding of structure-activity correlations that drive the development of new goods and technology, requires structural variety in these libraries. In current world, antibiotic resistance is a major ongoing problem which is developing a problematic scenario in public health. The implementation of isocyanide based multicomponent reactions uphold a significant potential in this regard. By utilizing such reactions, new antimicrobial compounds can be discovered and fight against such concerns. This study discusses recent developments in antimicrobial medication discovery using isocyanide-based multicomponent reactions (IMCRs). Furthermore, the article emphasizes the potential of IMCRs in the near future.

(1) Background: Health Care-Associated Infections (HAIs)are a significant public health problem worldwide favoring multidrug-resistant (MDR) microorganisms. The SARS-CoV-2 infection had a negative association with the increase in antimicrobial resistance, and the ESKAPE group had the most significant impact on HAIs. The study aimed to evaluate the bactericidal effect of high concentration O3 gas on some reference and ESKAPE bacteria. (2) Material and Methods: Four standard strains and four clinical or environmental MDR strains were exposed to high ozone doses at different concentrations and times. Bacterial inactivation (growth and cultivability) was investigated using colony counts and resazurin as a metabolic indicator. Scanning electron microscopy (SEM) was performed. (3) Results: The culture exposure to a high level of O3 inhibited the growth of all bacterial strains tested with a statistically significant reduction in colony count compared to the control group. The cell viability of S. aureus (MRSA) (99,6%) and P. aeruginosa (XDR) (29,2%) was reduced considerably, and SEM showed damage on bacteria after O3 treatment (4) Conclusion: High doses of ozone were able to interfere in the growth of all strains studied, evidencing that ozone-based decontamination approaches may represent the future of hospital cleaning methods.

Chitosan arouses large interest due to its properties and possible applications. Every year the number of publications and patents based on this polymer increases. Chitosan exhibits poor solubility in neutral and basic media limiting its use in such conditions. Another serious obstacle is directly related to its natural origin. Chitosan is not a single polymer with a defined structure but a family of molecules with differences in their composition, size, and monomer distribution. These properties have a fundamental effect on the biological and technological performance of the polymer. Moreover, some of the biological properties claimed are discrete. In this review, we discuss how chitosan chemistry can solve the problems related to its poor solubility and can boost the polymer properties. We focus on some of the main biological properties of chitosan and the relationship with the physicochemical properties of the polymer. Then, we visit two polymer applications related to green processes: the use of chitosan in the green synthesis of metallic na-noparticles and its use as support in biocatalyst. Finally, we briefly describe how making use of the technological properties of chitosan it is possible to develop a variety of systems for drug delivery

Staphylococcus aureus can develop resistance by mutation, tranfection or biofilm formation. Resistance was induced in S. aureus by growth in sub-inhibitory concentrations of ciprofloxacin for 30 days. The ability of the antimicrobials to disrupt biofilms was determined using crystal violet and live/dead staining. Effects on the cell membranes of biofilm cells was evaluated by measuring release of dyes and ATP and nucleic acids. S. aureus did not develop resistance to the AMPs but resistance increased to ciprofloxacin by 128 times after 30 passages. Only peptides reduced biofilms of ciprofloxacin resistant cells. The antibiofilm effect of melimine with ciprofloxacin was more (27%) than with melimine alone at 1X MIC (p < 0.001). Similarly, at 1X MIC the combination of Mel4 and ciprofloxacin produced more (48%) biofilm disruption than Mel4 alone (p < 0.001). Combinations of either of the peptides with ciprofloxacin at 2X MIC released  66 nM ATP, more than either peptide alone (p  0.005). At 2X MIC, only melimine in combination with ciprofloxacin released DNA/RNA which was 3 times more than released by melimine alone (p = 0.043). These results suggest the potential use of melimine and Mel4 with conventional antibiotics for the treatments of S. aureus biofilms.

The emergence of multi-drug resistant E. coli is an important matter of increasing considerable concern to global public health. The aim of this study was to investigate the incidence, antibiotic resistance pattern, phylogroups and genetic variation of E. coli isolates from raw milk, vegetable salad and ground meat samples. Methods: Culture-based techniques, Kirby-Bauer disk diffusion susceptibility testing, PCR and RAPD assays were used to determine the incidence rate, antimicrobial resistance pattern, phylogenetic groups and genetic diversity of the E. coli isolates. Results: E. coli isolates were highly resistant to amoxicillin (79.16%), trime-thoprim-sulfamethoxazole (70.83%), amoxicillin-clavulanic acid (62.50%), tetracycline (54.16%), chloramphenicol (54.16%), nitrofurantoin (54.16%), ampicillin (45.83%), streptomycin (45.83%), and kanamycin (33.33%); and completely susceptible to norfloxacin and azithromycin. 70.83% of the isolates were multi-drug resistant. Most E. coli isolates (46%) belonged to phylogroup A. RAPD with UBC245 primer categorized the isolates into 11 clusters. A high level of genetic di-versity was found among the isolates; however, 33.3% of the isolates were grouped in a major cluster (R5). Conclusions: Antibiotic resistance patterns are randomly distributed among the ge-netic clusters. Novel, practical, efficient food safety control and surveillance systems of multi-drug resistant foodborne pathogens are required to control the foodborne pathogen contamina-tion.

A derivative series of 3,4-dimethoxy-β-nitrostyrene were synthesized and identified including new compound 6. The effect of antimicrobial activity of 3,4-alkyloxy modification of β-nitrostyrene was investigated. A molecular docking was also performed to obtain information about their interactions with Protein Tyrosine Phosphatase 1B (PTP1B). PTP1B containing cysteine 215 and arginine 221 as essential active residues plays a key role in signaling pathways that regulate various cell functions of microorganisms, which also act as negative regulator in signaling pathways of insulin that are involved in type 2 diabetes and other metabolic diseases. Compound 5 and 6 were the most potent as fragment of PTP1B inhibitor based on molecular docking, but compound 5 was more effective against Candida albicans. These compounds interact with serine 216 and arginine 221 residues. However, further research is needed to investigate their potential medicinal use.

Xenorhabdus nematophila and Photorhabdus luminescens are entomopathogenic symbionts that produce several toxic proteins that can interfere with the immune system of insects. Here, we showed that outer membrane proteins (OMPs) could be involved as virulence factors during bacterial symbiont pathogenesis. Purified OMPs from bacterial culture were injected fifth instar larvae of Spodoptera exigua Hübner. Larvae were surveyed for fluctuations in total haemocyte counts (THC), granulocyte percentage (cellular defence), protease, phospholipase A2 (PLA₂), and phenoloxidase (PO) activities (humoral defence) at specific time intervals. Changes in the expression of the three antimicrobial peptides (AMPs), cecropin, attacin, and spodoptericin, were also measured. Larvae treated with both types of OMPs had more haemocytes than did the negative controls. OMPs of X. nematophila caused more haemocyte destruction than did the OMPs of P. luminescens. The OMPs of both bacterial species initially activated insect defensive enzymes post-injection, their activating fluctuated in different ways. Attacin, cecropin and spodoptericin were up-regulated by OMP injections more than in normal larvae. The expression of these three AMPs was maximal at four hpi with P. luminescens OMPs treatment. Expression of the three AMPs in X. nematophila treatment was irregular and lower than in the P. luminescens OMPs treatment. These findings provide insights into the role of OMPs of entomopathogenic nematode bacterial symbionts in countering the physiological defenses of insects.

The antiradical and antimicrobial activity of lignin and lignin-based films are both of great interest for applications such as food packaging additives. The polyphenol structure of lignin in addition to the presence of O-containing functional groups is potentially responsible for these activities. This study used DPPH assays to discuss the antiradical activity of HPMC/lignin and HPMC/lignin/chitosan films. The scavenging activity (SA) of both binary (HPMC/lignin) and ternary (HPMC/lignin/chitosan) systems was affected by the percentage of the added lignin: the 5% addition showed the highest activity and the 30% addition had the lowest. Both, scavenging activity and antimicrobial activity are depending on the biomass source showing the following trend: organosolv of softwood > Kraft of softwood > organosolv of grass. Testing the antimicrobial activities of lignins and lignin-containing films showed high antimicrobial activities against gram-positive and gram-negative bacteria at 35 °C and at low temperatures (0-7 °C). Purification of kraft lignin has a negative effect on the antimicrobial activity while storage has positive effect. The lignin release in the produced films affected the activity positively and the chitosan addition enhances the activity even more for both gram-positive and gram-negative bacteria. Testing the films against spoilage bacteria that grow at low temperatures revealed the activity of the 30% addition on HPMC/L1 film against both B. thermosphacta and P. fluorescens while L5 was active only against B. thermosphacta. In HPMC/lignin/chitosan films the 5% addition exhibited activity against both B. thermosphacta and P. fluorescens.

Mycobacteria are a large family of over 100 species, most of which do not cause diseases in humans. The majority of the mycobacterial species are referred to as nontuberculous mycobacteria (NTM), meaning they are not the causative agent of tuberculous (TB) or leprosy, i.e. Mycobacterium tuberculous complex and Mycobacterium leprae, respectively. The latter group is undoubtedly the most infamous, with TB infecting an estimated 10 million people and causing over 1.2 million deaths in 2017 alone (1). TB and leprosy also differ from NTM in that they are only transmitted from person to person and have no environmental reservoir, whereas NTM infections are commonly acquired from the environment (2) (3). It took until the 1950's for NTM to be recognised as a potential lung pathogen in people with underlying pulmonary disease and another 3 decades for NTM to be widely recognised by the medical community when NTM, particularly Mycobacterium avium complex (MAC) was recognised as the most common group of opportunistic pathogens in AIDS patients (4). This review focusses on an emerging NTM called Mycobacterium abscessus (M. abs). M. abs is a rapidly growing (RGM) NTM that is responsible for opportunistic pulmonary infections in patients with structural lung disorders such as cystic fibrosis (CF) and bronchiectasis (5), as well as a wide range of skin and soft tissue infections (SSTIs) in humans (6) (7). M. abs is a weakly staining Gram-positive mycobacterium that is neverand is, like other NTM, most often seen in soil and aquatic environments (8). The bacillus-shaped bacterium is 1-6µm long and 0.2-0.5µm in diameter, with curved ends and the presence of cord factor, or trehalose 6-6'-dimycolate, a glycolipid found in the cell wall of virulent species of mycobacteria that results in "serpentine cord" cell morphology is sometimes observed (8) (9). On solid growth medium, M. abs can display either a rough (M. abs-R) or smooth (M. abs-S) morphotype, with the rough morphotype displaying a more virulent phenotype than its smooth variant (10). The rough morphotype is characterised by irregular parallel filaments that form ridges across the colony, whereas a smooth morphology is displays a wet, smooth colony with no filaments or ridges (79). This morphology is driven by cell wall glycopeptidolipid (GPL); a loss of GPL results in the reversion from rough to smooth morphotype (80) (81). Moreover, it has been shown using human tissue culture models of infection that M. abs-R is able to persist and multiply within the host macrophage whereas M. abs-S lacks this capacity, hence its role in virulence (82). Like all other mycobacteria, M. abs are aerobic, non-motile and acid-fast organisms with a characteristically thick, lipid-rich cell wall that is hydrophobic. Due to their unusually impermeable, thick cell wall, mycobacteria are notoriously resistant to many antibiotics, disinfectants and heavy metals (11). When the genome of M. abs became available in 2009, elucidation of the resistance mechanisms of M. abs became an area of focus for scientific research, as the considerable threat it poses to public health became more apparent (12) (13) (14). In this review we will discuss how we came to understand the pathogen, how it is currently treated, as well as a discussion of drug resistance mechanisms and novel treatments currently in development.

The oceans harbor a great diversity of organisms, and have been recognized as an important source of new compounds with nutritional and therapeutic potential. Among these compounds, carbohydrate-based compounds are of particular interest because they exhibit numerous biological functions associated with their chemical diversity. This gives rise to new substances for the development of bioactive products. Many are the known applications of substances with glycosidic domains obtained from marine species. This review covers the structural properties and the current findings on the antioxidant, anti-inflammatory, anticoagulant, antitumor and antimicrobial activities of medium and high molecular-weight carbohydrates or glycosylated compounds extracted from various marine organisms.

Many marine animals use chemicals to defend themselves and their eggs from predators. Beyond their ecologically relevant functions, these chemicals may also have properties that make them beneficial for humans, including with biomedical and industrial applications. For example, some chemical defenses are also powerful antimicrobial or anti-tumor agents with relevance to human health and disease. One such chemical defense, Escapin, an L–amino acid oxidase in the defensive ink of the sea hare Aplysia californica, and related proteins have been investigated for their biomedical properties. This review details our current understanding of Escapin’s antimicrobial activity, including the array of chemicals generated by Escapin’s oxidation of its major substrates, L–lysine and L–arginine, and mechanisms underlying these molecules’ bactericidal and bacteriostatic effects on planktonic cells and the prevention of formation and removal of bacterial biofilms. Models of Escapin’s effects are presented, and future directions are proposed.

Staphylococcus aureus bacteria are one of the leading microorganisms responsible for nosocomial infections as well as being the primary causative pathogen of skin and wound infections. Currently, the therapy of staphylococcal diseases faces many difficulties, due to a variety of mechanisms of resistance and virulence factors. Moreover, a number of infections caused by S. aureus is connected with biofilm formation that impairs effectiveness of the therapy. Short cationic lipopeptides that are designed on the basis of the structure of antimicrobial peptides structure are likely to provide a promising alternative to conventional antibiotics. Despite the fact that many research groups have proved a high antistaphylococcal potential of lipopeptides, the lack of unified protocols in determination of antimicrobial activity may be the reason of inconsistency of the results. The aim of this study was to learn how the use of various bacteriological media as well as solvents may affect activity of lipopeptides and their cyclic analogs.

Accurate clinical diagnosis of patients presenting to primary care settings with acute sore throat remains challenging, often resulting in the over-prescribing of antibiotics. Using point-of-care tests (POCTs) to differentiate between respiratory infections is well-accepted, yet evidence on the application within primary care is sparse. We assessed the application of testing patients (n=160) from three family practices with suspected Streptococcal infections using rapid molecular tests (ID NOW Strep A2, Abbott). In addition to comparing clinical evaluation and prescription rates with either usual care or with testing, patients and staff completed a questionnaire about their experience of molecular POCT in primary care. The immediate availability of the result was important to patients (100%) and staff (≈90%) stated that molecular testing improved quality of care. Interestingly, only 22.73% of patients with a Centor score >2 tested positive for Strep A and overall, less than 50% of Centor scores 3 and 4 tested positive for Strep A with the ID NOW testing platform. The addition of rapid molecular POCTs to clinical assessment resulted in a 55- 65% reduction in immediate and deferred antibiotic prescriptions. The intervention was popular with patients and medical staff but was associated with increased cost and a longer appointment length.

Plant growth promoting rhizobacteria (PGPR) are a diverse group of microorganisms including genera such as Pseudomonas, Bacillus, Serratia, Enterobacter and Klebsiella. These bacteria have the ability to colonize roots externally and internally, and to directly enhance plant growth employing various mechanisms like phytohormone production and nutrient mineralization. These microbes can also promote plant growth indirectly by secreting antimicrobial compounds (e.g., siderophores, hydrogen cyanide) to antagonize root pathogens or by inducing defensive responses in the plant. Interestingly, there are also cases where production of antibiotic compounds such as 2,4-Diacetylphloroglucinol have the direct effect of enhancing plant growth and yield, irrespective of their biocontrol effects. The objective of this paper is to review publications showcasing PGPRs that have the capacity to both control root pathogens and stimulate plant growth, and to discuss what mechanisms might be involved.

Bacteria of the genus Staphylococcus are a significant a challenge for medicine, as many species are resistant to multiple antibiotics and even to all of the antibiotics used. One of the approaches to develop new therapeutics to treat staphylococcal infections is the use of bacteriophages specif-ic to these bacteria or lysins of such bacteriophages capable to hydrolyze the cell walls of these bacteria. In this study, a new bacteriophage St_134 specific to Staphylococcus epedermidis was de-scribed. This small podophage belonging to the Andhravirus genus showed relatively wide host range and was able to infect more than 60 strain of Staphylococcus spp., including a clinical strain from the Staphylococcus aureus complex. Two genes encoding different phage lysins were identi-fied in the Ste134 genome. Both lysins LysSte134_1 and LysSte134_2 were produced in Escherichia coli cells. Endolysin LysSte134_1 was demonstrated catalytic activity against a wide panel of staphylococcal peptidoglycans (4 species, 6 strains), was active against S. aureus and S. epidermidis planktonic cultures and destroyed biofilms formed by clinical strains of S. aureus and S. epider-midis.

Due to their wide range of uses in modern technology, nanomaterial’s of silver metallic (Ag-NPs) have engaged considerable concern, driving significant research with development efforts. This study focuses on investigating the antimicrobial properties of Ag-NPs, encompassing their production, characterization, and biological aspects. The eco-friendly extracellular biosynthetic method employed in this work utilized extracts from the marine fungus Aspergillus flavus MK4 as reducing agents for nanoparticle synthesis. Analyzing the colloidal Ag-NPs using UV-visible spectroscopy revealed a peak in absorbance at 460 nm, indicating the presence of plasmonic properties. The electrons imaging of internal structure (TEM) elucidated spherical shape of the Ag-NPs by 15 nm size. Testing against bacterial diversities (Gr-ve & Gr+ve) revealed potent antibacterial and antifungal efficacy. Cytotoxicity versus HepG-2 cell line was assessed using the MTT assay, and antioxidant properties were examined through the radical scavenging (DPPH) assay. In wise of their conceivable applications in the fields of antibacterial, anticancer, and wound-healing, the Ag-NPs that were synthesized exhibit promising features. With its powerful ability to synthesize silver nanoparticles (Ag-NP), Aspergillus flavus MK4 Aspergillus flavus MK4 can generate nanoparticles extensively characterized, demonstrating their antibacterial, antioxidant, anticancer, and wound-healing properties.

The study aims to evaluate the Quorum Sensing (QS) system inhibition against some Gram-positive and Gram-negative bacteria detected by molecular modeling of R. cathartica L. plant extract. R. cathartica L. methanol extract was evaluated in vitro. The research was carried out for the possible role and mechanism of R. cathartica L. The antibacterial activity of R. cathartica L. seed extract on some Gram-positive and Gram-negative strains was evaluated using culture-based and computational analysis. Gentamicin (CN; 30 µg/ml, Bioanalyse) was used as an antibacterial control of the extract on the production potential of QS-dependent virulence factors on Pseudomonas aeruginosa PAO1 was investigated. Phytochemical analysis resulted in the identification of 23 phenolic phytochemicals. R. cathartica L. extract was observed to have antimicrobial activity against Gram-positive and Gram-negative bacteria at different rates (11.3 mm-16 mm). The inhibitory effect of R. cathartica L. extract on P. aeruginosa PAO1 (elastase 61%, pyocyanin 18%, and biofilm 61%) was recorded moderately. Phytochemical analysis revealed that the main component of the extract is kaempferol. Therefore, the binding potential of kaempferol on QS system receptors was investigated via molecular docking. Computational analysis showed that kaempferol can inhibit the QS system by preventing competitive ligands from connecting to LasR. This study explored the activity and mechanism of action for a new green alternative against resistance. might provide a mechanism for R. cathartica L. seed extract components and thus provide a new avenue for using R. cathartica L. seed extract as a green antibacterial agent.

Melittin, a natural antimicrobial peptide, displays a broad-spectrum antimicrobial activity, which has caused increasing attention as a potential antibiotic alternative. However, melittin has not been used widely at present due to its high hemolysis and low proteolytic stability. In this study, N-terminal fatty acid was conjugated to melittin to develop new melittin-derived lipopep-tides (MDLs) for improving the limitation of melittin. Our results showed that, the antimicrobial activity of MDLs was increased by 2 to 16 times compared with native melittin, and the stability of these MDLs against trypsin and pepsin degradation was increased by 50 to 80%. Besides, the hemolytic of the MDLs decreased when the length of the carbon chain of fatty acids exceeded 10. Among them, the newly designed analog Mel-C8 showed optimal antimicrobial activity and protease stability. The antimicrobial mechanism studied revealed that the MDLs showed a rapid bactericidal effect by interacting with LPS or LTA and penetrating the bacterial cell membrane. In conclusion, we designed and synthesized a new class of MDLs with potent antimicrobial activity, high proteolytic stability, and low hemolysis through N-terminal fatty acid conjugation.

Few Sclerophyllous plants from the central coast of Chile have been systematically studied. This work describes the phytochemical composition and antimicrobial properties of Baccharis concava Pers. (sin. B. macraei), a shrub found in the first line and nearby the pacific coast between latitudes 29-38⁰S. B. concava has been traditionally used by indigenous inhabitants of today central Chile for their anthelmintic properties, wound healing properties and as a diuretic. Hydro-alcoholic extracts of B. concava were prepared from leaves and small branches. The qualitative phytochemical characterization indicated presence of alkaloids, steroids, terpenoids, flavonoids, phenolic and tannins compounds. The antimicrobial activity of this extract was assessed in a panel of microorganisms including Gram-positive, Gram-negative bacteria and pathogenic yeasts. The extract displayed important antimicrobial effects against Gram positive, Candida albicans, and Cryptococcus neoformans, but not against Gram negative, for which an intact Lipopolysaccharide (LPS) is apparently the determinant of resistant to B. concava extracts. The hydroalcoholic extract was then fractionated through a sephadex LH-20/methanol-ethyl acetate column. Followed, the fractions were pooled according to a similar composition that was visualized by TLC/UV analysis. Fractions obtained by this criterion were assessed for their antimicrobial activity against Staphylococcus aureus. The fraction presenting the most antimicrobial activity was HPLC-ESI-MS/MS analyzed obtaining a composition rich in structures derived from caffeoylquinic acid, dicaffeoylquinic acid and quercetin, among others. In conclusion, the extracts of B. concava show a strong antimicrobial activity probably due to their composition rich in metabolites derived from caffeoylquinic acid and quercetin, that in turn could be responsible for helping with wound healing, as reported from its ancient cultural use. In addition, the development of antimicrobial therapies based in the molecules found in B. concava could help to combat infection caused by pathogenic yeasts and Gram-positive bacteria, without affecting the Gram-negative microbiota.

Bacteremia and fungemia are significant causes of morbidity and mortality which frequently occur as co-infections with viral respiratory infections including SARS-CoV-2. It was aimed to evaluate the microorganisms isolated from blood cultures of SARS-CoV-2 positive and negative patients and investigate their antimicrobial resistance patterns. A retrospective analysis was performed with the total number of 22,944 blood cultures sent to the laboratory between November 2020 and December 2021. Blood cultures were performed on the BD Bactec automated system. Identification was performed using conventional methods, VITEK-2 and MALDI-TOF MS. Antibacterial/antifungal susceptibility tests were performed according to EUCAST/CLSI recommendations. SARS-CoV-2 tests were performed with RT-PCR. It was detected 1,630 culture positivity belonging to 652 patients. Totally 633 of 652 patients were tested for SARS-CoV-2; 118 (18.6%) were positive and 515 (81.3%) were negative. The bacteria and fungi isolated at the high-est rate in SARS-CoV-2 positive patients were methicillin-resistant coagulase negative staphylococci (MR-CoNS) (21.5%), Escherichia coli (12.4%), Klebsiella pneumoniae (12.4%), Candida albicans (1.65%) and Candida glabrata complex (1.65%); while in negative patients, E. coli (21.3%), MR-CoNS (13.5%), K. pneumoniae (12.05%), C. albicans (2.1%), Candida parapsilosis (1.1%) and Candida tropicalis (0.9%). The fact that the most common isolate was MR-CoNS in SARS-CoV-2 positive patients (p = 0.028); the detection of Acinetobacter baumannii was more frequent (p = 0.001) and the isolation of carbapenem-resistant K. pneumoniae was at a higher rate than in SARS-CoV-2 negative patients; also, the increase in multidrug-resistant strains indicate that healthcare-associated infec-tions should not be disregarded while focusing on the outbreak.

BMAP-18, derived from the N-terminal region of bovine myeloid antimicrobial peptide BMAP-27, demonstrated potent antimicrobial activity without cytotoxicity. This study aimed to compare the antibacterial, antibiofilm, and anti-inflammatory properties of BMAP-18, rich in aromatic phenylalanine residues, with its aliphatic analogue, BMAP-18-FL. Both aromatic BMAP-18 and aliphatic BMAP-18-FL exhibited equally potent antimicrobial activities against Gram-positive and Gram-negative bacteria, particularly methicillin-resistant Staphylococcus aureus (MRSA) and multidrug-resistant Pseudomonas aeruginosa (MDRPA). Mechanistic investigations employing SYTOX green uptake, DNA binding, and FACScan analysis revealed that both peptides acted by inducing membrane permeabilization and subsequent intracellular targeting. Moreover, both BMAP-18 and BMAP-18-FL effectively prevented biofilm formation and eradicated existing biofilms of MRSA and MDRPA. Notably, BMAP-18-FL displayed superior anti-inflammatory activity compared to BMAP-18, significantly reducing the expression levels of pro-inflammatory cytokines in lipopolysaccharide-stimulated macrophages. This study emphasizes the similarities and differences in the antimicrobial, antibiofilm, and anti-inflammatory properties between aromatic BMAP-18 and aliphatic BMAP-18-FL, providing valuable insights for the development of multifunctional antimicrobial peptides against drug-resistant bacteria.

The use of metal oxide nanoparticles as an alternative antimicrobial agent has gained attention due to the increasing problem of antibiotic resistance. Understanding its properties and potential benefits can contribute to the development of more effective and sustainable treatments in veterinary medicine. The aim of this study was to characterize TiO2-NP formulations and evaluate their antibacterial and wound healing abilities. The diameters and zeta potentials were determined using the Zetasizer in conjunction with dynamic light scattering. The agar-well diffusion method, time-kill kinetic assay and crystal violet assay were used to evaluate their antimicrobial activities. Wound healing assays were conducted both in-vitro and in-vivo. The study demonstrated that TiO2-NP formulations exhibit significant antimicrobial properties against various bacterial strains such as S. aureus and E. coli. No measurable E. coli growth was observed within a 15-mins period following exposure to TiO2-NP formulations. The TiO2-NP formation can improve wound healing by enhancing cell migration and collagen formation in both in-vitro and in-vivo conditions. In summary, our study suggests that TiO2-NP has the potential for use as an antimicrobial agent for animal wound treatment due to its ability to suppress bacterial growth and biofilm formation, as well as to enhance wound healing.

Methyl Salicylate (MS), the principal constituent of Wintergreen oil (WO) was obtained from acetyl salicylic acid (ASA) by sequential transesterification-esterification reaction promoted by NbCl5for the first time. The reagents were added simultaneously, and the reaction process involved the transesterification and esterification reactions, which were accompanied by thin layer chromatography and gas chromatography. The conversion rate via GC was 100%, and the MS yield was 94%. A cytotoxicity of 50% and 64% for cultured S. aureus and metastatic melanoma cells, respectively, was observed for a concentration of 0.6 mg/mL, whereas no cytotoxicity for non-tumor cells was observed for this concentration, and it is considered to be the optimum concentration.

The choice of antibiotic regimens to use in patients presenting with diabetic foot osteomyelitis and their duration differs according to the situation. Antibiotics play a more important role in the medical option where no infected bone has been resected while their role is reduced but not negligible in the case of surgical options. Some studies have reported the presence of biofilm structures in bone samples taken from patients with diabetic foot osteomyelitis which raises the question of the place of anti-biofilm antibiotic regimens in this setting. During the last two decades, clinical studies have suggested a potential benefit for anti-biofilm antibiotics, mainly rifampicin against staphylococci and fluoroquinolones against gram-negative bacilli. No data from randomized controlled studies have however been reported so far. The present work provides a summary of the available data on the question of the place of anti-biofilm antibiotics for the treatment of diabetic foot osteomyelitis but also the potential limitations of such treatments.

Objective: To evaluate the physical and chemical stability of the antibiotic temocillin at the recommended dose for severe infections and contained in infusion bags or elastomeric devices at different temperatures for its use in Outpatient Parenteral Antimicrobial Therapy (OPAT) programs.Method: Solutions of temocillin 12 g/L diluted in 0.9% sodium chloride were stored at 4ºC ± 2ºC, 25°C ± 2°C, 32°C ± 2°C and 37°C ± 2°C for 72 h both in polypropylene infusion bags and in polyisoprene elastomeric pumps. Physical and chemical stability were evaluated at 12, 24, 30 48 and 72 h after manufacturing. The solutions were considered stable if color, clearness and pH remained unchanged and if the percentage of intact drug was ≥90%. Results: There were no observed changes in color or clarity in any of the refrigerated (4°C) samples or in the samples incubated at 25ºC and 32ºC. At 37ºC, an increase in intensity of yellow color was observed at 30, 48 and 72 h in both infusion bags and elastomeric pumps samples. All samples remained within the pH range 6.84–6.06. At 4ºC, 25ºC and 32°C ± 2°C, temocillin attained the stability criteria of ≥90% of the original concentration for the whole experiment in both devices. At 37ºC, temocillin was stable for 24 h but its concentration dropped below 90% from that time point both in the infusion bags and in the elastomeric pumps.Conclusions: According to the data provided in this stability study, temocillin administrated by continuous infusion would be an appropriate candidate for the treatment of patients that can be discharge to complete therapy in an OPAT program.

Background. The European Centre for Disease Prevention and Control describes the community pharmacist as gatekeeper to the quality of antibiotic use. The pharmacist has the responsibility to guard safe and effective antibiotic use; however, little is known about how this is implemented in practice. Aims. To assess the feasibility of a method to audit the quality of antibiotic dispensing in community pharmacy practice and to explore antibiotic dispensing practices in Greece, Lithuania, Poland, and Spain. Methods. The Audit Project Odense methodology to audit antibiotic dispensing practice was adapted for use in community pharmacy practice. Community pharmacists registered antibiotic dispensing on a specifically developed registration chart and were asked to provide feedback on the registration method. Results. Altogether twenty pharmacists were recruited in four countries. They registered a total of 409 dispenses of oral antibiotics. Generally, pharmacists were positive about the feasibility of implementing the registration chart in practice. The frequency of checking for allergies, contraindications and interactions differed largely between the four countries. Pharmacists provided little advice to patients. The pharmacists rarely contacted prescribers. Conclusion. This tool seems to make it possible to get a useful picture of antibiotic dispensing patterns in community pharmacies. Dispensing practice does not seem to correspond with EU guidelines according to these preliminary results.

Background: The use of medicinal plants and their effective compounds as natural sources that have antioxidant properties, has been considered by researchers. Antioxidants are compounds that effectively inhibit the reaction of oxygen and nitrogen-free radicals with biomolecules in a variety of ways, reducing damage or preventing cell death, cardiovascular diseases, and cancers. Objective: In this study, chemical compounds of Adiantum capillus-veneris essential oil were used to evaluate its antioxidant and antimicrobial activity using water distillation and gas chromatography. Methods: The whole plant was dried at room temperature at 25 ° C and the distillation method with water with modifications was used using a Clevenger device for essential oil extraction. Gas chromatography-mass spectrometry (GC/MS) was used to identify the resulting essential oil compounds and the antioxidant and antibacterial activity of the essential oil was evaluated. Results: The most important chemical constituents of Adiantum capillus-veneris essential oil were carvone (33.00%), carvacrol (15.05%), hexadecanoic acid (7.02%), hexahydrofarnesyl acetone (4.25%) and n-nonanal (4.2%). The antibacterial activity of Adiantum capillus-veneris essential oils (mg/ml) was calculated and the highest antibacterial activity was determined by Staphylococcus aureus (8.23±1.07), Streptococcus pyogenes (12.46±1.62), and Diphtheroid (11.37±1.36) at a concentration of 100 mg/ml of essential oils. Conclusion: The results of the present study showed that the essential oil of Adiantum capillus-veneris prevented the growth of three pathogenic bacteria. This antibacterial property is due to the presence of flavonoid compounds in Adiantum capillus-veneris has the capacity for therapeutic and medical uses.

Neocarya macrophylla (Sabine) Prance (Nm, Chrysobalanaceae) is used traditionally as food, for medicinal spiritual and industrial purposes. It is also used as soap, dye, glue, fodder, termite repellent, firewood and for structural materials. Few studies on the physicochemical, nutritional contents, phytochemical and pharmacological activities have validated the benefits of Nm to humanity as food, in cosmetics and pharmaceutical products. The major bioactive constituents identified in the plant so far are steroids and flavonoids (such as stigmasterol, quercetin, catechin and its related glycosides). Extracts of the plant have shown good antivenom, antimicrobial, analgesic, anti-inflammatory, antimycobacterial, anthelmintic and antioxidant activities. Acute toxicity studies conducted have confirmed the plant to be toxic. More studies on the plant are required in order to exploit other biological activities as claimed by traditional healers and also to isolate more bioactive compounds. In addition, the safety and tolerability assessment of Nm should be undertaken due to its widespread usage.

For polymicrobial infections, AtbFinder utilizes a novel paradigm of the population response to antibiotics, enabling bacterial growth in the form of a mixed microbial community and selecting the antibiotics targeting not only the principal pathogen, but also those bacteria that support their growth. TGV medium allowed culturing a more diverse set of bacteria from polymicrobial biospecimens, compared with that achieved with the standard media and enabled, already within 4h, accurate selection of the antibiotics that completely eliminated all cultivatable bacteria from clinical samples. In conclusion, AtbFinder system may be a valuable tool in improving antibiotic selection, enabling targeted empirical therapy and accurate antibiotic replacement, which is especially important in high-risk patients.

The versatile one-pot green synthesis of a highly concentrated and stable colloidal dispersion of AgNPs was carried out using the self-assembled tannic acid without using any other hazardous chemicals. Tannic acid (Plant-based polyphenol) was used as a reducing and stabilizing agent for silver nitrate in a mild alkaline condition. The synthesized AgNPs were characterized for their concentration, capping, size distribution, and shape. The experimental results confirmed the successful synthesis of nearly spherical and highly concentrated (2281 ppm) AgNPs, capped with poly-tannic acid (AgNPs-PTA). The average particle size of AgNPs-PTA was found 9.90 ± 1.60 nm. The colloidal dispersion of synthesized nanoparticles was observed stable for more than 15 months in the ambient environment (25 oC, 65 % relative humidity). The synthesized AgNPs-PTA showed an effective antimicrobial activity against Staphylococcus Aureus Escherichia coli. Ag-PTA also exhibited enhanced catalytic properties. It reduces 4-nitrophenol into 4-aminophenol in the presence of NaBH4 with a normalized rate constant (Knor = K/m) of 615.04 mL·s-1·mg-1. Furthermore, AgNPs-PTA were stable for more than 15 months under ambient conditions. The unique core-shell structure and ease of synthesis render the synthesized nanoparticles superior to others, with potential for large-scale applications, especially in the field of catalysis and biomedical.

The most widely distributed bla_CTX-M gene on a global scale is bla_CTX-M-15. The dissemination has been associated with clonal spread and different types of mobile genetic elements. This study aimed to review and describe the genetic environments of bla_CTX-M-15 gene detected from Enterobacteriaceae in published literature from Africa. A literature search for relevant articles was done through PubMed, and Google Scholars electronic databases, 43 articles from 17 African countries were included in the review based on the eligibility criteria. Insertion sequences were reported as part of the genetic environment of bla_CTX-M-15 gene in 32 studies, integrons in 13 studies, and plasmids in 23 studies. In this review, five insertion sequences including ISEcp1, IS26, orf447, IS903, and IS3 have been detected associated with the genetic environment of bla_CTX-M-15 in Africa. Seven different genetic patterns were seen in bla_CTX-M-15 genetic environment. Insertion sequence ISEcp1 was commonly located upstream of the end of the bla_CTX-M-15 gene while insertion sequence orf477 was located downstream. In some studies, ISEcp1 was truncated upstream of bla_CTX-M-15 by insertion sequences IS26 and IS3. Class 1 integron (Intl1) was most reported to be associated with bla_CTX-M-15 (13 studies), with Intl1/dfrA17–aadA5 being the most common gene cassette array. IncFIA-FIB-FII multi-replicons and IncHI2 replicon types were the most common plasmid replicon types that horizontally transfer bla_CTX-M-15 gene. Aminoglycoside modifying enzymes, and plasmid-mediated quinolone resistance genes were commonly collocated with bla_CTX-M-15 gene on plasmids. This review revealed the predominant role of ISEcp1, Intl1and IncF plasmid in the mobilization and continental dissemination of the bla_CTX-M-15 gene in Africa.

Andean blueberries are wild berries grown and consumed in Ecuador which contain high values of bioactive compounds, mainly anthocyanins, with powerful antioxidant activity. The aim of this study was to evaluate the profile and contents of (poly)phenols and carotenoids in Andean blueberry by HPLC-DAD-MSn and determine a wide range of its biological activities. The antioxidant capacity of this fruit was evaluated in vitro by three different methods and in vivo using the zebrafish animal model, also the toxicity effect was determined by the zebrafish embryogenesis test. Besides, the antimicrobial activity and the capacity of Andean blueberry to produce hemagglutination in blood cells were evaluated. Finally, the bioaccessibility of (poly)phenols and related antioxidant capacity were determined in the different phases of an in vitro digestion. The global results indicated no toxicity of Andean blueberry, weakly bacteriostatic activity, and high contents of anthocyanins and antioxidant capacity, which were partially bioaccesible in vitro (~ 50 % at the final intestinal step), contributing to the knowledge of its health benefits for consumers and its potential use in the food and pharmaceutical industry as functional ingredient.

Edible coating gels developed from the Aloe vera plant have been used as a traditional medicine for about 3000 years. Aloe vera contains 110 potentially active constituents from six different classes: chromone and its glycoside derivatives; anthraquinone and its glycoside derivatives; flavonoids; phenylpropanoids and coumarins; phenylpyrone and phenol derivatives; and phytosterols and others. Apart from medicinal uses, Aloe gels have an important role in food preservation as edible coatings. They provide an edible barrier for atmospheric gases and moisture, and help to reduce the respiration and transpiration of fresh produce, which helps to preserve its postharvest quality. To date, numerous studies have been conducted on the postharvest use of Aloe vera gel. The present review article summarizes and discusses existing available information about the chemical constituents, antimicrobial activity, and food preservative characteristics of Aloe vera.

Fish currently provide 6.7% of all protein consumed by humans globally, nevertheless, aquaculture system has been linked to fish and environmental contamination and disease outbreak. This study aims to isolate, identify, and characterise, bacteria in fish and pond water as well as the antibiotic profile of detected Coliforms. The susceptibility of the isolates was tested using the Kirby-Bauer disc diffusion method on Mueller Hinton agar. A total of forty (40) isolates were isolated from the water samples of which (5) species were Gram Positive bacteria and 35 species of Gram Negative bacteria. The temperature for all ponds ranged from 25°C to 28°C. The mean bacteria count for pond C1 to T2 were 4.9 × 102, 4.9 × 102, 5.4 × 102, 2.5 × 102, 2.2 × 102, and 1.9 × 102 CFU/ml respectively. All isolates were 100% resistant to ceftazidime, cefuroxime and augmentin. More resistance to cefixime (80%) and gentamicin (73.3%) and nitrofurantoin (66.7%) was recorded. However, only 16.6% and 8.3% of the isolates were resistant to ciprofloxacin and ofloxacin respectively. The multiple antimicrobial resistance index (MARI) ranged from 0.5 to 0.9. The water quality parameters (temperature and pH) and the type of bacteria detected in all pond type did not differ significantly. The Multi-drug resistance bacteria detected could be pathogenic to fish and consumers.

A novel hybrid phosphite (C₄H₁₄N₂)[Co(H₂PO₃)₄]∙2H₂O was synthesized with 1,4-diaminobutane (dabn) as a structure-directing agent using slow evaporation method. Single crystal
X-ray diraction analysis showed that it crystallizes in the P-1 triclinic space group, with the following unit cell parameters (Å, °) a = 5.4814 (3), b = 7.5515 (4), c = 10.8548 (6), α = 88.001 (4), β = 88.707 (5), = 85.126 (5), and V= 447.33 (4) ų. The crystal structure was built up from corner-sharing [CoO₆]octahedrons, forming chains parallel to [001], which are interconnected by H₂PO_3^-pseudo-tetrahedral units. The diprotonated 1,4-butanediammonium molecules, residing between the parallel chains, interacted with the inorganic moiety via hydrogen bonds leading thus to the formation of the 3D crystal structure. The Fourier transform infrared spectrum showed characteristic bands corresponding to the phosphite group and the organic molecule. The thermal decomposition of the compound consisted mainly of the loss of the organic moiety and the water molecules. The biological tests exhibited significant activity against Candida albicans and Escherichia coli strains in all used concentrations, while less activity was pronounced when tested against Staphylococcus epidermidis and Saccharomyces
cerevisiae, while there was no activity against the nematode model Steinernema feltiae.

Antimicrobial resistance (AMR) is a recurring global problem, which constantly demands new antimicrobial compounds to challenge the resistance. It is well known that essential oils (EOs) have been known for biological activities including antimicrobial properties. In this study, EOs from seven aromatic plants of Asir region of southwestern Saudi Arabia were tested for their antimicrobial efficacy against four drug resistant pathogenic bacterial isolates (Staphylococcus aureus, Streptococcus pyogenes, Escherichia coli and Streptococcus typhimurium) and one fungal isolate (Candida albicans). Chemical compositions of EOs were determined by Gas chromatography-Mass Spectrometry (GC-MS). The results revealed that EOs from Mentha cervina, Ocimum basilicum and Origanum vulgare proved most active against all isolates with inhibitory zone range between17 to 45 mm. The lowest minimum inhibitory concentration (MIC) of 0.025mg/ml was observed for Staph. aureus and Streptococcus pyogenes with EO of Origanum vulgare. All the three EOs showed significant anti candida activity. Together form the results the EOs from Mentha cervina, Ocimum basilicum and Origanum vulgare demonstrated a significant antimicrobial efficacy against drug resistant microorganisms.

There is a great interest in finding antioxidants and products with antimicrobial activities from natural sources. The aim of this study was to obtain and identify the phenolic components and organic acids from Camellia oleifera cake. In addition, their antioxidant and antimicrobial activities were also investigated. The purity of phenolic components and organic acids obtained were 94.1 ± 0.5% w/w and 96.0 ± 0.3% w/w, respectively. There are 15 phenolic components have been detected and identified by HPLC-ESI-MS. Oxalic, citric, acetic, malic, and succinic acids are found to be major organic acids. The phenolic components and organic acids both had good antioxidant capacity, evaluated by 4 antioxidant activity assays (hydroxyl radical scavenging, superoxide radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl radical scavenging and lipid peroxidation inhibition). In addition, the phenolic components and organic acids exhibited significant inhibitory activity against bacteria Staphylococcus aureus, Escherichia coli, Bacillus subtilis, and fungi Mucor racemosus, Aspergillus oryzae, Rhizopus stolonifer. The phenolic components and organic acids from C. oleifera cake both showed good antioxidant capacity and exhibited antimicrobial activities. These results may be useful for the future use of phenolic components and organic acids from C. oleifera cake.

Dietary fibers regulate intestinal barrier function; however, the precise mechanisms remain unclear. This study investigated the effects of psyllium fibers on antimicrobial protein expression, focusing on the type II immunity and tuft cell-group 2 innate lymphoid cell (ILC2) circuit in the small intestine of the mouse. Supplemental psyllium fiber upregulated antimicrobial proteins, such as small proline-rich protein 2A (SPRR2A) and resistin-like beta (RELMβ), in mouse small intestine, evidently affecting cecal microbiota composition. Psyllium fibers also increased the RNA and protein expression of molecules related to ILC2 and tuft cells, such as IL-13, IL-25, DCLK1, Gfi-1b, SH2 domain-containing protein 3C, and Spi-B. In addition, ILC2 inhibitor (disulfiram) and bitter taste receptor blocker administration reduced psyllium-induced SPRR2A and RELMβ expression. Collectively, psyllium supplementation upregulates antimicrobial proteins such as SPRR2A and RELMß via the type II immune response and tuft cell-ILC2 circuit in the mouse small intestine.

Zinc nanoparticles (ZnNPs) open new opportunities for biomedical applications as a strategy against microbes and dye removal in an efficient way. The composite ZnNPs using Rhododendron arboreum (R. arboreum) stem bark were synthesized and characterized for UV-visible spectroscopy (UV-vis), Fourier transform infrared spectroscopy (FTIR), energy dispersive X-ray spectroscopy (EDX), scanning electron microscopy (SEM), and X-ray diffraction (XRD). The synthesized nanoparticles showed zones of inhibition of 23±0.09, 18±0.1 and 16±0.05 mm, against the Klebsiella pneumoniae (K. pneumoniae), Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli strains. The minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values against K. pneumoniae, S. aureus, and E. coli were found to be 34±0.21 and 72.71±0.47, 47±0.11 and 94.86±0.84 and 94±0.18 and 185.43±0.16 µg/mL, respectively. The biosynthesized ZnNPs resulted in significant eradication of the outer and inner membranes of the bacterial cells. Likewise, the synthesized ZnNPs showed time-dependent photocatalytic degradation activity and revealed 65% methyl orange dye degradation with an irradiation period of 6 hours. The findings of this study suggest the suitability of the novel R. arboreum stem bark-based ZnNPs as an effective ameliorant against bactericidal activities and photocatalysts for the removal of hazardous water contaminants.

Background: Bacteria can survive antibiotic exposure by mechanisms like tolerance without a shift in antimicrobial susceptibility. In this study, we investigated the presence of tolerance to three antimicrobials, ceftriaxone (CRO), azithromycin (AZM), and ciprofloxacin (CIP), in clinical isolates and WHO reference panel of N. gonorrhoeae and explored the prevalence between urogenital and anorectal infection sites. Methods: We examined 66 N. gonorrhoeae clinical isolates, evenly divided between anorectal and urogenital infection sites, using a modified tolerance disk (TD test) for three antibiotics. The isolates underwent a three-step incubation process wherein the isolates were exposed to an antibiotic disc for 20 hours of incubation (Step I), followed by the replacement of the antibiotic disc with a nutrient disc for overnight incubation (Step II) and additional overnight incubation with extra nutrients (Step III). Results: Four isolates were lost due to contamination. Of 62 clinical isolates, 7 exhibited tolerance to AZM, with 6 from anorectal and 1 from urogenital sites (p = 0.0496). Tolerance to CRO was observed in 11 isolates, which was significantly associated with the infection site, with 9 from the anorectum, and 2 from the urogenital site being tolerant (p = 0.02). Tolerance to CIP was found in 11 isolates, but was not significantly associated with the infection site. Tolerance was also detected in 8 (K, M, N, O, P, U, V, W) out of the 14 WHO (World Health Organization) reference strains, with varying patterns of tolerance to CRO (n=8), CIP (n=2) and AZM (n=1). Conclusion: This study identified CRO, AZM, and CIP tolerance in clinical Neisseria gonorrhoeae isolates. Significant variations in tolerance proportions between anorectal and urogenital infection sites, particularly for CRO, were observed. Additionally, tolerance was detected in WHO reference strains.

Abstract: Brassinosteroids (BR) are essential plant hormones that play a crucial role in regulating plant growth and development, as well as their resistance to abiotic and biotic stresses, including pathogen infections. In the context of plant im-munity, BR influence various processes such as the expression of genes related to pathogen defense, the production of antimicrobial compounds, and the re-inforcement of the plant cell structure. The aim of work is understand the role of BR in plant defense against abiotic and biotic stresses. BR are involved in the regulation of metabolic processes, water economy, and photosynthesis, contributing to increased plant resistance to abiotic stresses. The study discusses various mechanisms of BR action on plant immunity, including the regulation of gene expression related to defense, activation of the plant defense system, in-teraction with other plant hormones, regulation of water and salt balance, and influence on photosynthetic processes. In the context of plant immunity, BR influence various processes, including the expression of genes related to pathogen defense, the production of antimicrobial compounds, and the reinforcement of the plant cell structure. Additionally, BR are involved in the regulation of metabolic processes, water economy, and photosynthesis, con-tributing to increased plant resistance to abiotic and biotic stresses. The paper emphasizes the importance of further research on the role and mechanisms of action of BR in plant immunity, which may contribute to the development of more effective strategies for the use of BR in agriculture, horticulture, and plant protection.

Caused by pathogenic microorganisms, such as bacteria, parasites, fungi, among others, infectious diseases can spread directly or from one individual to another. According to the World Health Organization, these diseases are known to cause high mortality rates, severe burdens of disability and serious worldwide aftermaths. The inappropriate use of antibiotics in humans are the main origins of the development of drug-resistant pathogens, which reduce the efficacy of these therapies, thus accentuating the need to search for effective antimicrobials. Medicinal plants have served as starting material for the preparation of a number of antimicrobial agents. To this end, the present study highlights the green synthesis of Cocos nucifera-based nanomaterials and evaluation of the mechanistic basis of their antimicrobial action. Accordingly, Cocos nucifera extract was used to reduce different concentrations (5, 10 and 20 mM) of silver nitrate solution to afford silver nanoparticles (AgNPs). These entities were further incorporated onto activated carbons (obtained by chemical activation using sulphuric acid as activation agent) to generate the nanocomposites. The antimicrobial activity of the as-prepared nanomaterials was evaluated using the broth microdilution method, while, the antioxidant activity was assessed through standard methods, such as 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. Cytotoxicity of potent nanomaterials was assessed on Vero cells by spectrophotometric method. As a result, nanoparticles were successfully synthesized as evidenced by the color change of the solution from transparent to dark brown. Further characterization was carried out by UV-visible spectroscopy that showed an intense absorption spectrum at 433 nm. Fourier Transform Infrared Spectroscopy (FTIR) revealed the functional group moieties involved as a capping and reducing agent in the synthesis of AgNPs. The incubation of nanomaterials with selected bacterial and fungal strains led to significant inhibitory effects of these pathogens with minimum inhibitory concentrations ranging from 7.813 to 250 μg/ml. In antioxidant assays, the nanocomposites presented scavenging activities comparable to that of ascorbic acid. Cytotoxicity experiment revealed no toxic effects on the human mammalian cells Vero (range of selectivity indices: from &gt;4 to &gt;128). These results provide evidence of the implication of Cocos nucifera-based nanomaterials in targeting bacterial or fungal systems that mediate free-radical damage or by inhibiting the oxidative damage caused by selected bacteria and fungi, the most susceptible being Escherichia coli and Candida albicans, respectively.

In our previous studies, the marine-derived fungus Emericellopsis maritima BC17 was found to produce new eremophilane-type sesquiterpenoids on solid media. In order to explore its potential to produce more metabolites, E. maritima BC17 was subjected to a one strain-many compounds (OSMAC) analysis leading to the discovery of three new eremophilanes (1-3) and fourteen known derivatives (4-17) in the liquid media Czapek Dox and PDB. Their structures were established by extensive analyses of the 1D and 2D NMR, and HRESIMS data, as well as ECD data for the assignment of their absolute configurations. Antitumoral and antimicrobial activities of the isolated metabolites 1, 3, 11, and 15 were investigated. PR toxin 3-deacetyl (15) exhibited cytotoxic activity against HepG2, MCF-7, A549, A2058 and Mia PaCa-2 human cancer cell lines with IC₅₀ values ranging from 2.5 to 14.7 µM. In addition, 15 exhibited selective activity against methicillin-sensitive S. aureus ATCC29213 at the highest concentration tested of 128 µg/mL.

The antimicrobial quantitative structure–activity relationship of plant flavonoids against Gram-positive bacteria was established in our previous works, and the cell membrane was confirmed as a major site of action. To investigate whether plant flavonoids have similar antibacterial effects and mechanisms against both Gram-negative and Gram-positive bacteria, here, the minimum inhibitory concentrations (MICs) of 37 plant flavonoids against Escherichia coli were determined using the microdilution broth method, and then the correlation between their lipophilic parameter ACD/LogP or LogD_7.40 value and their MIC was analyzed. Simultaneously, the correlation between the ACD/LogP or LogD_7.40 value and the MIC of 46 plant flavonoids reported in literature against E. coli was also analyzed. Both sets of results showed that there is a significant correlation between the LogP value and the MIC of plant flavonoids against Gram-negative bacteria. However, it is difficult to effectively predict the MIC of plant flavonoids against Gram-negative bacteria from their lipophilic parameters. By comparing two regression curves derived from plant flavonoids against Gram-negative and Gram-positive bacteria, it was further discovered that the antibacterial activities of most plant flavonoids against Gram-negative bacteria are stronger than those against Gram-positive bacteria when their LogP values are less than about 3.0, but the opposite is true when their LogP values are more than about 3.6. Moreover, this comparison also suggests that unlike mainly acting on the cell membrane of Gram-positive bacteria, plant flavonoids have multiple mechanisms against Gram-negative species, while the cell membrane is also an important action site among them. Combined with the correlation analyses between the enzyme inhibitory activity and the LogP value of the reported flavonoids, it was further suggested that DNA gyrase is another important target of plant flavonoids against Gram-negative bacteria.

The wound management sector has attracted considerable attention due to the increasing challenge posed by antimicrobial resistance (AMR) and the specialized care required for chronic wounds. Effective wound care involves selecting appropriate dressings tailored with antimicrobial agents to prevent bacterial infection. Among various types of wound dressings, fibers and electrospun fibers, with their unique characteristics, have emerged as innovative new materials. However, the rise of AMR necessitates the exploration of new antimicrobial agents for wound dressings, particularly for addressing bacterial pathogens like methicillin-resistant Staphylococcus aureus (MRSA). Endophytic fungi, known for producing diverse bioactive compounds, including novel antibacterial agents, represent a promising source of such new agents. This study tested thirty-two endophytic fungi from thirteen distinct Australian native plants for their antibacterial activity against S. aureus, the most common wound-associated bacteria. Ethyl acetate (EtOAc) extracts from fungal culture filtrates exhibited inhibitory effects against both methicillin-sensitive S. aureus ATCC 25923 and MRSA strains M173525 and M180920. DNA sequence analysis was employed for fungal identification, with EtOAc extracts from the most active sample, EL 19 (Chaetomium globosum), selected for further bactericidal and antibiofilm testing against the chosen bacteria. Biofilm of S. aureus ATCC 25923 was reduced by 55% by EtOAc extracts of EL 19 at 1/2 × MIC. To demonstrate the potential application in wound dressing materials, three different concentrations of the extract were incorporated into Polycaprolactone fiber mats through electrospinning, with resultant inhibition of S. aureus ATCC 25923 being observed. This research underscores the potential of endophytic fungi from Australian plants as sources of substances effective against common wound pathogens. Further exploration of the responsible compounds and their mechanisms could facilitate the development of wound dressings effective against MRSA and innovative biofilm-resistant electrospun fibers, contributing to the global efforts to combat AMR.

Despite substantial heterogeneity of studies, there is evidence that antibiotics commonly used in primary care influence the composition of the gastrointestinal microbiota in terms of changing the composition and/or diversity. Benzyl isothiocyanate (BITC) from the food and medicinal plant nasturtium (Tropaeolum majus) is known for its antimicrobial activity and is used for the treatment against infections of the draining urinary tract and upper respiratory tract. Against this background, we raised the question whether 14 d nasturtium intervention (3 g daily, N=30 healthy females) could also impact the normal gut microbiota composition. Spot urinary BITC excretion highly correlated with a weak, but significant antibacterial effect against Escherichia coli. A significant increase in human beta defensin 1 as parameter for host defense was seen in urine and exhaled breath condensate (EBC) upon verum intervention. Pre-to-post analysis revealed that mean gut microbiome composition did not significantly differ between groups, nor did circulating serum metabolome. On an individual level, partly large changes were observed between sampling points, though. Explorative Spearman rank correlation analysis in subgroups revealed associations between gut microbiota and the circulating metabolome, as well as between changes in blood markers and bacterial gut species.

With the growing demand for personal protective equipment (PPE) in the face of the pandemic events caused by SARS-COV-2, the opportunity arises for the development of materials with characteristics such as antimicrobial, antiviral, antifungal activity, etc. The use of polymeric nanocomposites based on polyester/copper offers an alternative of great interest due to the versatility of the raw material and the high efficiency of copper as an antimicrobial additive. In this study, textile fibers prototypes with different Cu nanoparticles (CuNP) content were produced using melt-spinning to obtain bi-component multifilament fibers, and melt-blowing to obtain non-woven fabrics. The prototypes were tested against different pathogenic microorganisms such as S. aureus, E. coli, and C. albicans. It was shown that bi-component fibers offer more excellent protection against pathogens, while non-woven fabric only shows activity against E. coli. It was possible to identify that the CuNP were confined exclusively in the outer cover of the bi-component fibers, using different analytical techniques, which may be associated with the increase in antimicrobial activity, compared to the fibers present in the non-woven fabric, even when they present the same CuNP content.

Pathogenic microorganisms can cause a range of infectious diseases and are often treated with antimicrobial agents. The rise of antimicrobial resistance caused by inappropriate use of these agents in various settings has become a global health threat. There is, therefore, a need to find new and effective agents to combat infections caused by resistant pathogens. Nanotechnology has seen significant growth and development in recent years and has a wide range of applications in various fields, including health, agriculture, and industry. This novel area offers the potential for the synthesis of nanoparticles (NPs) with antimicrobial activity, such as iron oxide nanoparticles (IONPs). The use of IONPs is a promising way to overcome antimicrobial resistance or pathogenicity because of their ability to interact with several biological molecules and to inhibit microbial growth. This review focuses on the most common green synthesis methods for producing IONPs using bacteria, fungi, plants, and organic waste, as well as the most common methods for the characterization of these IONPs. Finally, it summarizes their application as promising antibacterial, antifungal, antiparasitic, and antiviral agents.

: Introduction: Discovering compounds with antibacterial activity is crucial in the current fight against antibiotic-resistance. Material and Methods: We generate two QSAR model to design six new heteroaryl drug candidates; we assessed the antibacterial properties of the compounds against nine ATCC strains, the majority being part of the ESKAPE group, that include Enterococcus faecalis, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and also Salmonella enterica and Escherichia coli. We performed a synergic assay in which we combined PB4, a compound that we have previously tested in published studies, with GC-VI-70, one of the new compounds with the best cytotoxicity/MIC profile. We tested sub-MIC concentrations of PB4 with five antibiotics (linezolid, gentamycin, ampicillin, erythromycin, rifampin and imipenem) to examine the synergic effect on the ATCC strains. To evaluate compounds’ cytotoxicity, we performed a 24-hour and 48-hour 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay on Colorectal Adenocarcinoma (CaCo-2) cells. The antibiotics were tested, alone and in combination with PB4. Results: PB4 lowered the MIC measured for GC-VI-70 and for the various antibiotics employed in clinical use, and all the compounds presented in this study have cytotoxic activity against cells. Conclusions: These compounds show promising use in combination with antibiotics to improve their effectiveness at low concentrations, to prevent unwanted cytotoxic effects.

The development of antimicrobial resistance to conventional antibiotics is a major global health challenge. Infections caused by multidrug-resistant gram-negative bacteria have been named one of the most urgent global health threats. Considerable efforts are devoted to developing new antibiotic drugs and investigating the mechanism of antibiotic resistance. Recently, Anti-Microbial Peptides (AMPs) have emerged as a new platform for the target and design of novel drug resistant anti-microbial agents promising a new therapeutic strategy. AMPs are rapid, potent, possess an unusually broad spectrum of activity, and have shown efficacy as topical agents. Unlike traditional therapeutics that interfere with essential bacterial enzymes, AMPs interact with microbial membranes through electrostatic interactions and physically damage cell integrity. However, naturally occurring AMPs have limited selectivity and modest efficacy. Therefore, recent efforts have focused on the development of synthetic AMP analogs as suitable drug targets. This work explores the development of novel antimicrobial agents which mimic the structure of graft-copolymers and mirror the mode of action of an AMP. Chitosan-graft-polypeptide side chains are synthesized by the ring-opening polymerization of N-carboxyanhydrides of L-lysine and L-leucine initiated from the functional groups of chitosan. The derivatives with random- and block-copolymer side chains are explored as drug targets. These graft copolymer systems exhibit activity against clinically significant pathogens and disrupt biofilm formation. This work highlights the potential of chitosan-graft-polypeptide structures in biomedical applications.

It is urgent to find new antibiotic classes to replenish the empty development pipeline of antibiotics. Recently, pyrrolobenzodiazepines (PBDs) with a C8-linked aliphatic-heterocycle have been identified as a new broad spectrum antibiotic class with activity against Gram-negative bacteria. The active imine moiety of the reported lead pyrrolobenzodiazepine compounds was replaced with amide to obtain the non-DNA binding and non-cytotoxic dilactam analogues to further understand the structure activity relationship and improve the safety potential of this class. The synthesized compounds were tested against panels of multidrug resistant Gram-positive and Gram-negative bacteria, including WHO priority pathogens. Minimum inhibitory concentrations for the dilactam analogues ranged from 4 – 32 mg/L for MDR Gram-positive bacteria, compared to 0.03 to 2 mg/L for the corresponding imine analogues while they were found to be inactive against MDR Gram-negative bacteria, with an MIC &gt;32 mg/L, compared to an MIC of 0.5 to 32 mg/L. A molecular modelling study suggests the lack of imine functionality also affects the interaction of PBDs with DNA gyrase. This study suggests the presence of N10-C11 imine moiety is crucial for broad spectrum activity of pyrrolobenzodiazepines.

This study assesses the secondary metabolites, minerals, antimicrobial, antioxidant, and anticancer properties of Micromeria fruticosa plant different botanical parts (leaf, stem, root, flower) extracted with various solvents. The plant samples were sequentially obtained using different solvents (n-hexane, ethanol and water) through steeping. Then, each of the extracts was further analyzed by using gas chromatography–mass spectrometry (GC-MS). Moreover, the extracts were bio-assayed to test their antioxidant, antibacterial, and anti-cancer activities. Quali-quantitative analysis of M. fruticosa crude extracts revealed the occurrence of 27 secondary metabolites were identified including mainly monoterpenes, sesquterpenes, and fatty acids, with varying quantities. Some of the major bioactive compounds included, Menthone (5.42-30.05%), Oleamide (3.40-32.20%), Pulegone (10.66-64.1%), and Menthol (3.61-100.0%), which were detected mostly in all plant parts with significant quantities. Several antioxidant minerals, mainly, Fe, Zn, and Mn, were detected with the highest amounts in the Micromeria water extracts. Results from antimicrobial assays showed that the water extract of leaves exhibited the highest DPPH scavenging activity (89.73%) followed by the water extract of flowers (80.07%) at a concentration of 100 μg/mL. The water extract of stems showed greater antimicrobial activity against all the tested gram negative and positive bacteria (Methicillin-resistant Staphylococcus aureus, Staphylococcus aureus, Escherichia coli, and Shigella sonnie). The leaves ethanolic and stem aqueous extracts had a strong antimicrobial activity against E. coli. and C. albicans. Flower aqueous extract demonstrated the highest cytostatic effect on the colon cell line by reducing viability up to 30.4%, followed by the leaf ethanol extract with 38.6% cell viability reduction at 1000 µg/mL. In conclusion, extraction solvents influenced the recovery of phytocompounds and the highest pharmacological activities of the different extracts could be correlated to the presence of additional bioactive compounds. Our results suggest that M. fruticosa plant is a promising source of natural products with antioxidant, anti-microbial and anti-cancer properties for potential nutraceutical, therapeutic, and functional food applications. , , , , , ,

(1) Background: Disinfection of medical devices designed for clinical use associated or not with the growing area of tissue engineering is an urgent need. However, traditional disinfection methods are not always suitable for some biomaterials, especially those sensitive to chemical, thermal, or radiation. Therefore, the objective of this study was to evaluate the minimal concentration of ozone gas (O3) necessary to control and kill a set of sensitive or multi-resistant Gram-positive and Gram-negative bacteria. The cell viability, membrane permeability, and the levels of reactive intracellular oxygen (ROS) species were also investigated; (2) Material and Methods: Four standard strains and a clinical MDR strain were exposed to low doses of ozone at different concentrations and times. Bacterial inactivation (cultivability, membrane damage) was investigated using colony counts, resazurin as a metabolic indicator, and propidium iodide (PI). A fluorescent probe (H2DCFDA) was used for the ROS analyses; (3) Results: No reduction in the count colony was detected after O3 exposure, compared to the control group. However, the cell viability of E. coli (30%), P. aeruginosa (25%), and A. baumannii (15%) was reduced considerably. The bacterial membrane of all strains was not affected by O3 but presented a significant increase of ROS in E. coli (90 ± 14%), P. aeruginosa (62.5 ± 19%), and A. baumanni (52.6 ± 5%); (4) Conclusion: Low doses of ozone were able to interfere in the cell viability of most strains studied, and although it does not cause damage to the bacterial membrane, increased levels of reactive ROS are responsible for causing a detrimental effect in the lipids, proteins, and DNA metabolism.

Biogenic-Silver nanoparticles emerge as new nanosilver platfmorm that allow to obtain silver nanoparticles via “green chemistry”. In our study we obtained biogenic-Silver nanoparticles from Iris tuberosa leaves extract. Nanoparticles were characterized by UV-vis spectroscopy, dinnamical light scattering technique and Transmission electron microscope, showing spheric and irregular nanoparticles with 5 to 50 nm in diameter. Antioxidant and antimicrobial properties were evaluated against typical microbial contaminants found in cosmetic products, showing high antioxidant and antimicrobial properties. We formulated a natural moisturizing cream with biogenic-silver nanoparticles to evaluate the preservative efficiency trought challenge test, confirming that our nanoparticles are a promising alternative to use as cosmetic preservative.

The members of the Liliaceae family have been regarded as an excellent source of biologically active compounds. However, the work on antimicrobial potential and characterization of the bioactive fractions of Lilium philadelphicum flower is limited and needs to be explored. The present study reports the antimicrobial potential, anti-inflammatory and anticancer potential of the bioactive fraction extracted from the flower of L. philadelphicum (Red Lily) and characterization of these bioactive compounds. The antimicrobial activity was tested against nine different Gram-positive and Gram-negative bacterial strains. The minimum inhibitory concentration (MIC) values of methanolic extract of L. philadelphicum flower against Acinetobacter bouvetii, Achromobacter xylosoxidans, Bacillus subtilis MTCC 121, Candida albicans MTCC 183, Klebsiella pneumoniae MTCC 3384, and Salmonella typhi MTCC 537 were 25, 50, 12.5, 50, 100 and 50 μg mL-1, respectively. The phytochemical analysis of the extract reveals the presence of phenols, flavonoids, tannins, terpenoids, glycosides, coumarins, and quinones. The cytotoxicity of the partially purified compound against the HepG2 cell line in MTT assay demonstrates up to 90% cell viability with a bioactive compound concentration of 50 μg/ml. However, with the increase in bioactive compound concentration up to 1000 μg/ml results into nearly 80% cell viability, just a minor decline in cell viability suggests the importance of bioactive compounds for suitable therapeutic applications. Spectroscopic studies of the bioactive compound by UV-Visible spectroscopy, FT-Infra Red spectroscopy, Gas Chromatography-Mass Spectrometry (GCMS) as well as its phytochemical analysis suggests the presence of terpenoids moiety, responsible for the antimicrobial property of L. philadelphicum flower.

Pseudomonas aeruginosa is a Gram-negative bacillus included among the six "ESKAPE" microbial species with an outstanding ability to "escape" currently used antibiotics and developing new antibiotics against it is of the highest priority. Whereas minimum inhibitory concentration (MIC) values against Pseudomonas aeruginosa have been used previously for QSAR model development, disk diffusion results (inhibition zones) have not been apparently used for this purpose in the literature, and we decided to explore their use in this sense. We developed multiple QSAR methods using several machine learning algorithms (Support vector classifier, K Nearest Neighbors, Random Forest Classifier, Decision Tree Classifier, AdaBoost Classifier, Logistic Regression, and Naive Bayes Classifier). The main descriptors used in building the models belonged to the families of adjacency matrix, constitutional descriptors, first highest eigenvalue of Burden matrix, centered Moreau-Broto autocorrelation, and averaged and centered Moreau-Broto autocorrelation descriptors. A total of 32 models were built, of which 28 were selected and stacked to create a meta-model. In terms of balanced accuracy, the best performance was provided by KNN, SVM and AdaBoost algorithms, but the ensemble method had slightly superior results in nested cross-validation.

To combat infections on biomedical devices, antimicrobial coatings have attracted considerable attention, including coatings comprising naturally occurring antimicrobial peptides (AMPs). In this study the aim was to explore performance upon extended challenge by bacteria growing in media above samples. The AMPs LL37, Magainin 2, and Parasin 1 were covalently grafted onto a plasma polymer platform, which enables application of this multilayer coating strategy to a wide range of biomaterials. Detailed surface analyses were performed to verify the intended outcomes of the coating sequence. Samples were challenged by incubation in bacterial growth media for 5 and 20 hrs. Compared with the control plasma polymer surface, all three grafted AMP coatings showed considerable reductions in bacterial colonization even at the high bacterial challenge of initial seeding at 1x107 CFU, but there were increasing numbers of dead bacteria attached to the surface. All three grafted AMP coatings were found to be non-toxic to primary fibroblasts. These coatings thus could be useful to produce antibacterial surface coatings for biomaterials, though possible consequences arising from the presence of dead bacteria need to be studied further, and compared to non-fouling coatings that avoid attached dead bacteria.

Community pharmacists are involved in antimicrobial stewardship through self-care advice and delivering medications for uncomplicated infections. Objectives This mixed methods study aimed to identify opportunities to enhance the role of community pharmacists in the management of patients with suspected or confirmed urinary tract infection (UTI). Methods Data collection was through a service user survey (n=51) and pharmacist surveys and semi-structured interviews before (16 interviews, 22 questionnaires) and after (15 interviews, 16 questionnaires) trialling UTI leaflets designed to be shared with patients. Data were analysed inductively using thematic analysis and descriptive tabulation of quantitative data. Results Twenty-five percent (n=13/51) of service users with urinary symptoms sought help from a pharmacist first and 65% (n=33/51) were comfortable discussing their urinary symptoms with a pharmacist in a private space. Community pharmacists were confident as the first professional contact for service users with uncomplicated UTI (n=13/16, 81%), but indicated the lack of a specific patient referral pathway (n=16/16, 100%), the need for additional funding and staff (n=10/16, 62%), and the importance of developing prescription options for pharmacists (5/16, 31%). All community pharmacists reported playing a daily role in controlling antimicrobial resistance by educating service users about viral and bacterial infections and promoting a healthy lifestyle. Enhancing their role will need greater integrated working with general practices and more prescribers based in community pharmacy. Conclusion This study suggests that community pharmacists could play a greater role in the management of uncomplicated UTI. The current reconfiguration of primary care in England with primary care networks and integrated care systems could provide a real opportunity for this collaborative working with potential learning for international initiatives.

High Brassicaceae consumption reduces the risk of developing several cancer types, probably due to their glucosinolate amount. Extracts from Sinapis nigra L. and Sinapis alba L. have been obtained from leaves and seeds under different conditions using ethanol/water mixtures because well accepted by food industry. The EtOH/H2O 8:2 mixture gives better yields in glucosinolate amounts from grinded seeds, mainly sinalbin in S. alba and sinigrin in S. nigra. The highest antiproliferative activity in both non-tumour and tumour cell lines was induced by S. alba seeds extract. To evaluate whether Sinapis spp effect was only due to glucosinolate content or it was influenced by the extracts’ complexity, cells were treated with extracts or glucosinolates, in the presence of myrosinase. Pure sinigrin did not modify cell proliferation, while pure sinalbin was less effective than the extract. The addition of myrosinase increased the antiproliferative effects of the S. nigra extract and sinigrin. Antiproliferative activity was correlated to MAPKs modulation, which was cell and extract-dependent. Cell-cycle analysis evidenced a proapoptotic effect of S. alba on both tumour cell lines and of S. nigra only on HCT 116. Both extracts showed good antimicrobial activity in disc diffusion tests and on ready-to-eat fresh salad. These results underline the potential effects of Sinapis spp in chemoprevention and food preservation.

Current research in the field of antimicrobials is focused on the development of novel antibiotics and antimicrobial agents to counteract the huge dilemma that the human population is mainly facing in regards to the rise of bacterial resistance and biofilm infections. Host Defense peptides (HDPs) are a promising group of molecules for antimicrobial development as they share unique characteristics suitable for antimicrobial activity including their broad spectrum of activity and potency against bacteria. AamAP1 is a novel HDP that was identified through molecular cloning from the venom of the North African scorpion Androctonus amoeruxi. In vitro antimicrobial assays revealed that the peptide displays moderate activity against different strains of Gram-positive and Gram-negative bacteria. Additionally, the peptide proved to be highly hemolytic and displaying significantly high toxicity against mammalian cells. In our study, a novel synthetic peptide analogue named A3 was designed from the naturally occurring scorpion venom host defense peptide. The design strategy depended on modifying the amino acid sequence of the parent peptide in order to increase its net positive charge, percentage helicity and optimize other physico-chemical parameters involved theoretically in HDPs activity. Accordingly, A3 was evaluated for its in vitro antimicrobial and anti-biofilm activity individually and in combination with four different types of conventional antibiotics against clinical isolates of multi-drug resistant (MDR) Gram-positive bacteria. A3 was also evaluated for its cytotoxicity against mammalian cells. A3 displayed potent and selective in vitro antimicrobial activities against a wide range of MDR Gram-positive bacteria. Our results also showed that combining A3 with conventional antibiotics displayed a synergistic mode of action which resulted in decreasing the MIC value for A3 peptide as low as 0.125 µM. These effective concentrations were associated with negligible toxicities on mammalian cells. In conclusion, A3 exhibits enhanced activity and selectivity when compared with the parent natural scorpion venom peptide. The combination of A3 with conventional antibiotics may be pursued as a potential novel treatment strategy against MDR and biofilm forming bacteria.

Selenocyanates form an interesting class of organic selenium compounds as they serve as multifunctional agents (being the precursors of seleninic acids and diselenides in synthetic chemistry and as antimicrobial and cytotoxic agent in biology) and, due to their similarity with better known thiocyanates promise high biological activity. Yet whilst selenocyanates are common in synthetic chemistry, they are rarely considered in pharmaceutical design. Arylmethyl selenocyanates (1-13) have been synthesized and an insight into their structural properties using X-ray crystallography has been obtained. The compounds subsequently have been evaluated for their potential antimicrobial, nematicidal and cytotoxic activity. ADMET properties in vitro, using mutagenicity (AMES) and permeability (PAMPA) tests, have been determined. The compounds exhibit pronounced activity against various strains of bacteria (both Gram-positive and Gram-negative) and yeasts. Among them, benzylselenocyanate (1) represents the most active anti-ESKAPE agent, with potent antibacterial activity, especially against multidrug resistant MRSA strains (HEMSA 5). Our results demonstrate that the arylmethyl selenocyantes are not only non-mutagenic but also possess moderate cytotoxic activity against cancer cells.

Application of toxic antibacterial agents is considered necessary to control prevalent fresh water microorganisms in evaporative cooling water systems, but these agents can adversely affect the environment and human health. Alternatively, natural antibacterial water chemistry has been applied in industrial cooling water systems for over 10 years with excellent results. The tower water chemistry method concentrates natural salts in highly-softened water to produce elevated pH and dissolved solids, with low calcium and magnesium. This practice conserves water while generating only a small volume of non-toxic natural salt concentrate for cost efficient separation and disposal if required. This review presents a novel perspective of natural antimicrobial chemistry for inhibiting parasitic microbiome functional relationships within the bio-triad of Legionella outbreaks, "Trojan Protozoans" and biofilms. The review further examines practical application and function of polyvalent metal ions in the inhibition of biofilms. Reducing global dependence on toxic antibacterial agents discharged to the environment is an emerging concern due to their impact on the natural microbiome, plants, animals and humans. Discharge of antibacterial agents also contributes to development of pathogen resistance. Use of natural antibacterial chemistry can play a key role in managing the cooling water environment in a more ecologically sustainable manner.

Several plant species produce mixtures of odorous and volatile compounds known as essential oils (EOs). These mixtures play important roles in nature and have been utilized by man for pharmaceutical and agrochemical purposes. There are more than 3000 EOs reported in the literature with approximately 300 having commercial use, including the oils from Eucalyptus species. Such oils are rich in monoterpenes and have found applications as pharmaceuticals, agrochemicals, food flavorants and in the perfume industry. Such applications are related to their diverse biological and organoleptic properties. In view of their importance, we review in this article up to date information concerning chemical composition and biological activities of essential oils from different species of Eucalyptus. Among the 900 species and subspecies of the Eucalyptus genus¸ we examined 68 species. The studies associated with these species were conducted in 27 countries. We have focused on the antimicrobial, acaricide, insecticide and herbicide activities, hoping that such information will contribute in the advances of the research in this field. It is also intended that the information herein described can be useful in the rationalization of the use of Eucalyptus EOs as components for new pharmaceutical and agrochemical applications as well as food preservatives and flavorants.

Bacterial infections and resistance to antibiotic drugs represent the highest challenges to public health. The search for new and promising compounds with anti-bacterial activity is a very urgent matter. In order to promote the development of platforms enabling to the discovery of compounds with anti-bacterial activity, Fourier Transformed Mid-Infrared (FT-MIR) spectroscopy associated with the machine learning algorithms were used to predict the impact of compounds extracted from Cynara cardunculus against Escherichia coli cells. According to the plant tissue (seeds, dry and fresh leaves, and flowers) and the solvents (ethanol, methanol, acetone, ethyl acetate, and water), compounds with different compositions concerning, phenol content, antioxidant, and antimicrobial activity were obtained. Principal component analysis of spectra, allowed to discriminate compounds that inhibit the E. coli growth, according to the conventional assay. The supervised classification models enabled the prediction of the compound's impact on the E. coli growth, with the accuracy for the test data: Partial least squares-discriminant analysis of 94%; Support vector machines of 89%; k-Nearest neighbor of 72%; and a Backpropagation network of 100%. According to the promising results, the integration of FT-MIR spectroscopy with machine learning presents a high potential to promote the discovery of new compounds with antibacterial activity, thereby streamlining the drug exploratory process.

Research on titanium oxo complexes (TOCs) are usually focused on their structure and photocatalytic properties. Findings from these investigations spurred our interest in exploring also their potential biological activities. In this study, we focused on the synthesis and structure of a compound with the general formula [Ti8O2(OiPr)20(man)4] (1), which was isolated from the reaction mixture of titanium(IV) isopropoxide with mandelic acid (Hman) in a molar ratio of 4:1. The structure (1) was determined using single-crystal X-ray diffraction, while spectroscopic studies provided insights into its physicochemical properties. To assess the potential practical applications of (1), its microcrystals were incorporated into a polymethyl methacrylate (PMMA) matrix, yielding composite materials of the type PMMA + (1) (2 wt.%, 5 wt.%, 10 wt.%, and 20 wt.%). The next stage of our research involved the antimicrobial activity evaluation of the obtained materials. Investigations carried out demonstrated antimicrobial activity of pure (1) and its composites (PMMA + (1)) against both Gram-positive and Gram-negative strains. Furthermore, MTT tests conducted on the L929 murine fibroblast cell line confirmed the lack of cytotoxicity of these composites. Our study identified (1) as a promising antimicrobial agent, also for producing composite coatings.

Background : Probiotics are composed of microorganisms that have positive effects on health when consumed in prescribed quantities. Lately, studies have attempted to establish this role of probiotics in enhancing health. Aim : The aim of this study was to compare the antifungal activity of 3 different probiotics against Candida albicans.Methodology :This was an in-vitro study. 3 types of commercially available probiotics - Bifilac, Pre pro HS and VSL-3 were cultured separately with Candida albicans and were placed under incubation. The maximum zone of inhibition was recorded for each of the probiotic solutions.Results : In this study, it was found that among the three probiotic products, Bifilac exhibited a maximum zone of inhibition of 13mm at concentration of 100µL against C. albicans, while Pre pro HS and VSL-3 showed zone of inhibition of 11mm at concentrations of 50µL and 100µL, respectively.Conclusion : Within the limits of the present study, This study could prove that probiotics can be considered as an alternative and safe treatment option for treatment of Oral candidiasis infections.

Tuberculosis (TB) caused by Mycobacterium tuberculosis remains a predominant cause of mortality, especially in low- and middle-income nations. Recently antimicrobial peptides were discovered that at low concentrations could stimulate the growth of M. tuberculosis (hormetic response). In this study, such a peptide was used to investigate the effects on the time to positivity (TTP). A systematic substitution analysis of peptide 14D was synthesized using Spot synthesis technology, resulting in 171 novel peptides. Our findings revealed a spectrum of interactions, with some peptides accelerating M. tuberculosis growth, potentially aiding in faster diagnostics, while others exhibited inhibitory effects. Notably, peptide NH2-wkivfiwrr-CONH2 significantly reduced the TTP by 25 hours compared to the wild-type peptide 14D, highlighting its potential in improving TB diagnostics by culture. Several peptides demonstrated potent antimycobacterial activity, with a minimum inhibitory concentration (MIC) of 20 µg/mL against H37Rv and a multidrug-resistant M. tuberculosis strain. Additionally, a reduction in the formation of cord-like structures was observed, which is indicative of reduced virulence and transmission potential. This study underscores the multifaceted roles of antimicrobial peptides in TB management, from enhancing diagnostic efficiency to offering therapeutic avenues against M. tuberculosis.