A series of derivatives of trans-3-(2,4,6-trimethoxy phenyl)-4,5-dihydro isoxazolo-4,5-bis(aroylcarbohydrazide) and of trans-3-(2,4,6-trimethoxyphenyl)4,5-dihydroisoxazolo-4,5-bis[carbonyl-(4’phenyl)thiosemi- carbazide (9) were synthesized from trans-3-(2,4,6-trimethoxyphenyl)-4,5-dihydro-4,5-bis(hydrazenocarbonyl) Isoxazole (8). The structures of the Compounds were elucidated by elemental and spectral (IR, NMR, and MS) analysis. The compound 9 show activity against some bacterial species. Whereas, no activity was observed for compounds 10a, 10b and 10c against all bacterial species. The antioxidant activity of new compounds has been screened. Compound 9 showed higher antioxidant activity using the DPPH and ATBS method.

Incorporating nanoparticles into plant cultivation has been shown to improve growth parameters and alter the bioactive component compositions of many plant species, including Curcumin longa. The aim of the current study was to investigate the effects of foliar application of zinc oxide na-noparticles on the content of bioactive compounds and their antibacterial activities against poten-tial bacterial pathogens. To this end, C. longa leaves were treated with different doses of ZnO NPs to see how they affected bioactive component composition. The effect of different doses of ZnO NPs on the accumulation of bisdemethoxycurcumin, demethoxycurcumin, and curcumin in etha-nolic extracts of C. longa rhizomes was evaluated using high-performance liquid chromatography (HPLC). When compared to the control treatment, foliar spraying with (5 and 40 mgL-1) ZnO NPs increased bisdemethoxycurcumin, demethoxycurcumin, and curcumin levels by approximately (2.69 and 2.84), (2.61 and 3.22), and (2.90 and 3.45) fold, respectively. It was looked at to see if the ethanolic extracts made from the plantlets might change in terms of their phytochemical makeup and antibacterial properties. Furthermore, the results revealed that C. long-ZnO-NPs displayed antibacterial activity against S. aureus and P. aeruginosa tested bacterium strains, but made little attempt against E. coli. The MIC for P. aeruginosa was 100 g/mL. Time-kill studies also revealed that ZnO-NPs at 4 MIC killed P. aeruginosa, Actinobacteria baumannii, and Bacillus sp. after 2 hours, while S. aureus did not grow when treated with 4xMIC of the extract for 6 hours. The strongest antibacterial activity was seen with extract from plantlets grown without nanoparticles for P. aeruginosa, whereas it was seen with extract from plantlets grown in the presence of 5 mg/L ZnO-NPs for E. coli, S. aureus, and P. aeruginosa. These findings show that ZnO-NPs are a pow-erful enhancer of bioactive compound production in C. longa, a trait that can be used to combat antibiotic resistance in pathogenic bacterial species.

Tin (IV) oxide nanoparticles (SnO2 NPs) have received a lot of interest because of their interesting features. SnO2 NPs have proven productive in a range of fields, including water purification, supercapacitors, batteries, antibacterial and antioxidant agents, and others. SnO2-based nanoparticles found a wide range of applications after incorporating materials with varying chemical compositions. SnO2 NPs and their nanocomposites have been used effectively as antibacterial agents against various pathogenic bacteria, photocatalysts for dye degradation, and electrode materials for supercapacitors (SCs). This article covers the characteristics of SnO2 NPs, SnO2 nanocomposite materials, applications of SnO2 NPs and their composite materials, including antibacterial, energy storage, and photocatalysis, as well as some significant recent studies.

Management of chronic inflammation and wounds has always been a key issue in the pharmaceutical and healthcare sector. Curcumin (CCM) is an active ingredient extracted from turmeric rhizomes that has antioxidant, anti-inflammatory, and antibacterial activities, thus showing significant effectiveness toward wound healing. However, its shortcomings such as poor water solubility, poor chemical stability and fast metabolic rate limit its bioavailability and long-term use. In this context, hydrogels appear to be a versatile matrix for carrying and stabilizing drugs due to the biomimetic structure, soft porous microarchitecture, and pleasant biomechanical properties. The drug loading/releasing efficiencies can also be controlled by use of highly crystalline and porous metal organic frameworks (MOFs). Here, a flexible hydrogel composed of sodium alginate (SA) matrix and CCM-loaded MOFs was constructed for long-term drug release and antibacterial activity. The morphology and physicochemical properties of composite hydrogels were analyzed by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), ultraviolet visible spectroscopy (UV-Vis), Raman spectroscopy and mechanical property tests. The results showed that the composite hydrogel was highly twistable and bendable to mechanically comply with human skin. The as-prepared hydrogel could capture efficient CCM for slow drug release as well as effective killing of bacteria. Therefore, such composite hydrogel is expected to provide a new management system for chronic wound dressings.

Hydroxamic acid (HA) derivates displayed antibacterial and antifungal activities. HA with various numbers of carbon atoms (C2, C6, C8, C10, C12 and C17), complexed to different metal ions Fe(II/III), Ni(II), Cu(II) and Zn(II) were evaluated for their antimycobacterial activities and their anti-biofilm activities. Some derivates, among others HA12Fe2, inhibited the development of Mycobacterium tuberculosis, Mycobacterium bovis BCG and Mycobacterium marinum biofilms and could even attack pre-formed Pseudomonas aeruginosa biofilm. Proteomic profiles showed that the potential targets of HA10FeCl were mainly related to mycobacteria stress adaptation, involving cell wall lipid biosynthesis, drug resistance and tolerance, siderophore metabolism. This study provides new insights regarding the antimycobacterial activities of the HA and their complexes, especially about their potential antibiofilm activities.

Enteric septicemia of catfish, columnaris disease, and streptococcosis, caused by Edwardsiella ictaluri, Flavobacterium columnare, and Streptococcus iniae, respectively, are the most common bacterial diseases of economic significance for the pond-raised channel catfish Ictalurus punctatus industry. Several management practices are used by catfish farmers to prevent large financial losses from these diseases such as the use of commercial antibiotics and other chemicals. In order to discover environmentally benign alternatives, using a rapid bioassay, we evaluated a crude extract from the roots of muscadine Vitis rotundifolia against these fish pathogenic bacteria and determined that the extract was most active against F. columnare. Subsequently, several isolated compounds from the root extract were further evaluated against F. columnare. Among these isolated compounds, (+)-hopeaphenol (2) and (+)-vitisin A (3) were found to be the most active against F. columnare, with 24-h 50% inhibition concentrations of 4.0±0.7 and 7.7±0.6 mg/L, respectively, and minimum inhibitory concentrations of 9.1±0 mg/L for each compound. Efficacy testing of 2 and 3 is necessary to further evaluate the potential for these compounds to be used as antibacterial agents for managing columnaris disease.

Human milk reduces risk for necrotizing enterocolitis in preterm infants. Necrotizing enterocolitis occurs in the ileocecal region where thousands of milk protein-derived peptides have been released from digestion. Digestion-released peptides may exert bioactivity, such antimicrobial and immunomodulatory activities, in the gut. In this study, we applied mass spectrometry-based peptidomics to characterize peptides present in colostrum before and after in vitro digestion. Sequence-based computational modeling was applied to predict peptides with antimicrobial activity. We identified more peptides in undigested samples, yet the abundances were much higher in the digested samples. Heatmapping demonstrated highly different peptide profiles between undigested and digested samples. Four peptides (αS1-casein [157–163], αS1-casein [157–165], β-casein [153–159] and plasminogen [591–597]) were selected, synthesized and tested against common pathogenic bacteria associated with necrotizing enterocolitis. All four exhibited bacteriostatic, though not bactericidal, activities against Klebsiella aerogenes, Citrobacter freundii and Serratia marcescens, but not Escherichia coli.

The North African E. pinnata is not known as a traditional medicinal plant but modern research has revealed its extracts richness in anti-oxidants and components of medicinal value. Despite its wide distribution and medicinal value, the species remains taxonomically and phytochemically un-derstudied, especially in Algeria. Here we compare three ecotypes of E. pinnata from the humid, sub-humid and semi-arid areas. The comparison was carried out using classical techniques of multivariate plant morphology, pollen grains size and shape, chromosome numbers, pollen fer-tility, anti-oxidant and antibacterial activities. Significant differences were revealed for all criteria except pollen fertility and antibacterial activity. The semi-arid ecotype showed to be a remote group in relation to the two others except for pollen size where the remote group was the sub-humid ecotype. Pollen size appeared positively correlated with karyotype length. The results (mg GAE/g EXT) of the antioxidant activity tests of the “humid”, “sub-humid” and the “semi-arid” plant groups are as follows, respectively; TPC: 50.79±0.51, 52.04±1.05 and 56.89±0.46; DPPH: 71.18±2.24, 86.39±3.02 and 95.67±2.02; RP: 11.09±1.24, 17.21±0.75 and 25.88±0.26. The inhibition area diameter in the antibacterial activity test varied from 9.25±1.06 mm (Semi-arid plants vs Pseudo-monas aeruginosa) to 12.00±1.41 mm (Sub-humid plants vs Escherichia coli).

Bovine respiratory disease (BRD) is the leading cause of morbidity and mortality in cattle raised in North America. At the feedlot, cattle are subject to metaphylactic treatment with macrolides to prevent BRD, a practice that may promote antimicrobial resistance and has resulted in an urgent need for novel strategies. Mannheimia haemolytica is one of the major bacterial agents of BRD. The inhibitory effects of two amphipathic, α-helical (PRW4, WRL3) and one β-sheet (WK2) antimicrobial peptides were evaluated against multidrug-resistant (MDR) M. haemolytica isolated from Alberta feedlots. WK2 was not cytotoxic against bovine turbinate (BT) cells by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. All three peptides inhibited M. haemolytica, with WK2, being the most efficacious against multiple isolates. At 8-16 µg/ml, WK2 was bactericidal against Mh 330 in broth and at 32 µg/ml in the presence of BT cells, reduced the population by 3 logs CFU/ml without causing cytotoxic effects. The membrane integrity of Mh 330 was examined using NPN (1-N-phenylnaphthylamine), and ONPG (o-Nitrophenyl β-D-galactopyranoside) with both the inner and outer membranes being compromised. Thus, WK2 may be a viable alternative to the use of macrolides as part of BRD prevention and treatment strategies.

Objective: The aim of the study was to characterize varieties of Moringa alfileria honey (unfloral and polyfloral) from Saudi Arabia based on antibacterial, antioxidant activities, physicochemical, melissopalynological analysis, total phenolic and flavonoid contents. Material and Methods: The fresh 376 honey samples (3 kg of each) were kindly provided by Alnahal aljwal Company, 2021 flowering season. The honey samples collected in sterile universal glass containers and kept at 2– 8°C until tested. Antibacterial, antioxidant activities and physiochemical analysis were done. Determination of sediment content, total grains, moisture content, water-soluble solids, acidity, electrical conductivity, total sugars content, inverted sugars, glucose (g/100 g), fructose (g/100 g), total glucose + fructose, fructose/ glucose ratio, sucrose (g/100 g), diastase enzyme activity and HMF were calculated. As well as total phenolic and flavonoid contents Results: Antibacterial activity and physiochemical analysis of honey samples w varied. All parameters studied were significantly different (P < 0.05) among all honey varieties. The results of the physiochemical analysis were compared with Saudi National Standard, Codex standard, as well as published data in the literature. Conclusion: It was obvious that the honey quality was varied based on the botanical origins

The increased emergence of multidrug-resistant Helicobacter pylori influences the prevention of stomach cancer. Zingiber officinale is a plant usually used in folk medicine to treat a variety of diseases involving infections, nausea, vomiting, peptic ulcer, dyspepsia, and inflammation. This study was conducted to evaluate the ability of Z. officinale extract to combat resistant H. pylori. The disc diffusion, microdilution, and microplate assays were performed to evaluate the susceptibility to antibiotics, and the antibacterial and antibiofilm activities of the Z. officinale extracts. Using the checkerboard method, the combined effects of the gentamicin and Z. officinale extract were investigated. In addition, anti-inflammatory activity and GC-MS analysis were determined by the modified protocol. According to the findings, H. pylori isolates exhibited resistance rates of 56.33, 50.0, and 45.85 for metronidazole, gentamicin, and tetracycline, respectively. The methanolic extract of Z. officinale had the strongest effectiveness against resistant H. pylori isolates with MIC of 20.0 to 50.0 µg/ml against both H. pylori isolates and the stranded strain NCTC 11637. Z. officinale extract suppress the biofilm formed by H. pylori isolates with a percentage of 92.96% at 50.0µg/ml, compared with 97.19% for gentamicin at the same concentration. According to FICI values, combination of methanolic Z. officinale extract to gentamicin increases bacterial sensitivity to such drugs. Moreover, the Z. officinale extract exhibits strong anti-inflammatory activity. The GC-MS analysis of Z. officinale extract exhibits 17 different chemical compounds. Conclusions: The Z. officinale extract contain the anti-inflammatory compound gingerol as the main constituent which inhibits the growth of H. pylori and its biofilm, are a promising natural therapeutic alternative or enhance antibiotics activity

Eucalyptus, a therapeutic plant mentioned in the ancient Algerian pharmacopeia, specifically two species belonging to the Myrtaceae family - E. radiata and E. cinerea, were investigated in this study for their antibacterial, antioxidant, and anti-inflammatory properties. The study used aqueous extracts (AE) obtained from these plants, and the extraction yields were found to be dif-ferent. The in vitro antibacterial activity was evaluated using a disc diffusion assay against three typical bacterial strains. The results showed that E. radiata EAq was effective against all three strains, while E. cinerea EAq was only effective against E. coli. Both extracts displayed significant antioxidant activity compared to BHT. The anti-inflammatory impact was evaluated using a pro-tein (BSA) inhibition denaturation test. The E. radiata extract was found to inhibit inflammation by 75% at a concentration of 250 g/ml, significantly higher than the placebo. Ellagic acid, a pri-mary phytochemical found in the extracts, demonstrated noteworthy toxic and pharmacokinetic characteristics and a maximum binding energy of -7.53 kcal/mol for its anti-TyrRS activity in sili-co. The study suggests that the extracts and their primary phytochemicals could enhance the effi-cacy of antibiotics, antioxidants, and non-steroidal anti-inflammatory drugs (NSAIDs). As phar-maceutical engineering experts, we believe this research contributes to developing natural-based drugs with potential therapeutic benefits.

There is a growing interest in a potential use of essential oils (EOs) as a possible alternative for chemical pesticides. The formulation between different EOs could maximize the single biological efficacy by synergic mechanism. The aim of the current study was to evaluate the biological activity of three prepared blended oil formulations (BOFs) derived from Origanum vulgare L. (oregano) and Salvia officinalis L. (sage) compared to each parent EO. The chemical composition of each single studied EO has been revealed using GC-MS analysis. The three BOFs have been prepared as following: i) 25% oregano EO + 25% sage EO (BOF-I); ii) 25% oregano EO + 5% sage EO (BOF-II); iii) 5% oregano EO + 25% sage EO (BOF-III). The antibacterial activity of the new BOFs has been evaluated against Bacillus megaterium, B. cereus and Xanthomonas campestris, whereas, the antifungal activity has been carried out against Botrytis cinerea, Penicillium italicum and Fusarium oxysporum. The possible phytotoxic effect of the new BOFs has been evaluated on Lepidium sativum (garden cress), Solanum lycopersicum (tomato) and Lactuca sativa (lettuce) following the seed germination and radicle elongation assay. GC-MS analysis revealed that the oregano EO composed mainly from thymol, p-cymene and carvacrol with 76.0, 5.7 and 3.2 %, respectively. Whereas, salvia EO, the GC-MS analysis showed that the relevant predominant constituents were trans-thujone and camphor with 37,9 and 13,9 %, respectively. Results demonstrated that the tested BOFs possess antimicrobial effect higher than each parent EO. In particular, BOF-II showed the highest effect against all tested bacteria. Regarding the antifungal activity, BOF-II showed the highest significant antifungal effect against all tested fungi. Results showed also that both BOF-I and BOF-III explicated a moderate effect against B. cereus and all tested fungi compared to single EOs. In addition, the three BOFs showed notable phytotoxic effect against all three tested plants, particularly BOF-I. Whereas, the single sage EO at 25% showed the lowest significant phototoxic effect indicating its possible using as natural herbicides.

The thionamide antithyroid drugs were discovered largely following serendipitous observations by numerous researchers in the 1940s who found that sulfhydryl-containing compounds were goitrogenic in animals. Prof. Edwin B. Astwood was the first to use these compounds to treat hyperthyroidism. In this review, we summarize the history of the development of these drugs and the coordination possibility of 2-thiouracil and its derivatives, as well as the biological activities of some of its complexes. Some of them are used as agents for the treatment of tuberculosis, and arthritis, others have bactericidal and fungicidal activity, the third cytotoxic properties, and could be used to treat various types of cancer.

Keywords: Antibacterial activity, Antioxidant activity, Bioactive compounds, Elementary analysis, Nutritional and phytochemical composition, Seaweed.

Essential oils (EOs) have gained economic importance due to their biological activities, and increasing amounts are demanded everywhere. However, substantial differences between the same essential oil samples from different suppliers are reported due to numerous companies involved in EOs production and the continuous development of online sales. The present study investigates the antibacterial and antibiofilm activities of 2-4 samples of five commercially available essential oils (Oregano, Eucalyptus, Rosemary, Clove, and Peppermint oils) from different manufacturers. Their effects were evaluated in vitro on Gram-positive and Gram-negative bacteria (Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa). The antibacterial efficacy (ABE%) and antibiofilm efficacy (ABfE%) were determined spectrophotometrically at 562 and 570 nm using microplate cultivation techniques. The essential oils' calculated parameters were compared with those of three standard broad-spectrum antibiotics: Amoxicillin/Clavulanic acid (AMC), Gentamycin (GEN), and Streptomycin (STR), active on tested bacteria. The results showed that at the first dilution (D1 = 2.5 mg/mL), all essential oils (EOs) exhibited antibacterial activity against Gram-positive and Gram-negative bacteria. On S. aureus and E. coli, EOs had considerable antibacterial effects (ABE = 79.70—92.80%, respectively, 71.30 ‒ 94.00%). The highest antibacterial effects of commercially available EOs were against P. aeruginosa because all exhibited a significant antibiofilm activity. Their antibiofilm efficacy intensively decreased on E. coli and S. aureus. Generally, the samples with different manufacturers of the same EO showed similar effects. Only Clove and Peppermint oils samples displayed a higher variability associated with active metabolites' different contents, maybe due to various zones of harvesting raw material, numerous technologies involved in EOs obtaining processes, and complex interactions between components.

Helicobacter pylori infection constitutes a silent pandemic of global concern. In the last decades, the alarming increase of multidrug resistance evolved by this pathogen has led to a marked drop in the eradication rates of traditional therapies worldwide, encouraging scientific community to discover and develop new antimicrobial strategies. In the present work, we identified a battery of novel drug-like HsrA inhibitors with MIC values ranging from 0.031 to 4 mg/L against antibiotic-resistant strains of H. pylori. Most of these novel antimicrobials exhibited minor effects against both Gram-negative and Gram-positive species of human microbiota. The most potent anti-H. pylori candidate demonstrated a high therapeutic index, additive effect in combination with metronidazole and clarithromycin, as well as a strong antimicrobial action against Campylobacter jejuni, another clinically relevant pathogen of phylum Campylobacterota. Transcriptomic analysis suggested that in vivo inhibition of HsrA triggered lethal global disturbances in H. pylori physiology, including the arrest of protein biosynthesis, malfunction of respiratory chain, detriment in ATP generation, and oxidative stress. The novel drug-like HsrA inhibitors described here constitute valuable candidates to a new family of narrow-spectrum antibiotics that allow overcoming the current resistome, protecting from dysbiosis, and increasing therapeutic options for novel personalized treatments against H. pylori.

Abstract Antibacterial activities can be improved using mixed ligands. Mixed ligands involved in this research are sodium sulfadiazine (Na-sfz) and dithiocarbamate (ai-dtc). One-pot synthesis was used to synthesize ligand of aniline dithiocarbamate (ai-dtc) and the corresponding coordination compounds of [VO(sfz)(ai-dtc)] and [Zn(sfz)(ai-dtc)]. Crystals of ai-dtc, which grew from the solution when refrigerated after five days, were diffracted with technique of single crystal x-ray crystallography to reveal the structure. Other characterization techniques involving physicochemical parameters, FT-IR, UV-Vis and NMR (1H NMR and 13C NMR) were carried out on ligands of ai-dtc, sfz and corresponding coordination compounds. Differences in results of FT-IR, UV-Vis and NMR between ligands and their respective metal ions confirmed the coordination. The in vitro antibacterial studies showed that the ligands (not the metal complexes) had modest activity against Gram negative bacteria: Staphylococcus aureus, whereas, the coordination compounds had modest activities against the Gram negative bacteria: Escherichia coli and Pseudomonas aeruginosa.

The main purpose of our research is the evaluation of the efficacity of solvent polarity on phenolic composition, as well as the antibacterial, and antioxidant activities of extract of Moroccan Mentha aquatica L., leaves. To attempt these objectives, the HPLC-DAD was used to identify the biomolecules. The total amount of phenolic and flavonoid content was determined using the Folin-Ciocalteu and aluminum trichloride processes as well as the DPPH, RP, and TAC tests were used to evaluate the antioxidant capabilities. In addition, by employing both in vitro and in silico analysis through the microdilution method, the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extracts were assessed against multidrug-resistant bacteria. Furthermore, the High-Performance Liquid Chromatography (HPLC) analysis indicated that all extracts of M. aquatica were abundant in noteworthy phytochemical compounds, especially gallic acid, vanillic acid, chlorobenzoic acid, quercetin, and kaempferol. Furthermore, the results indicated that the total phenolic content was higher in hydroethanolic extract (62.19 ± 1.19 mg GAE/g DW) in contrast to the acetonic and aqueous extracts (22.22 ± 0.64, and 22.44± 0.57 mg GAE/g DW) respectively. Similarly, the aqueous ethanol extract contained the greatest flavonoid concentration, with values of 29.15± 0.09 mg QE/g DW when compared with the other extracts. The seam extract poses excellent antioxidant power with an IC50 of 0.06 ± 0.00 mg/mL for the DPPH test, and lower RP with EC50 of 80± 0.00 µg/ml when compared with acetonic and aqueous extract (370± 0.00 and 460± 0.01 µg/mL) respectively. Moreover, the hydroethanolic extract has a high level of TAC 75.09± 2.00 mg EAA/g DW, followed by aqueous extract carrying a value of 28.53 ± 1.36 mg EAA/g DW. The antibacterial capacity is ranged between 0.78 ± 0.05 mg/mL and 12.60 ± 0.00 mg/L. The results of the in-silico study demonstrated that quercetin, vanillic acid, and naringenin components contribute to the antioxidant capability. While gallic acid, kaempferol, and quercetin components are attributed to the antibacterial capacity.

Sodium phenyl dithiocarbamate (pl-dtc) as a ligand was prepared from the reaction of aniline (C6H5-NH2) and carbon(IV) sulfide (CS2) in the presence of sodium hydroxide via method of one-pot synthesis. Two coordination compounds ([VO(sfz)(pl-dtc)] and [Zn(sfz)(pl-dtc)]) from respective oxovanadium (IV) sulfate hydrate and zinc (II) chloride were prepared with mixed ligands involving sodium sulfadiazine (sfz) and the synthesized pl-dtc crystals, also via the method of one-pot synthesis. Structural analyses of the ligand and coordination compounds were assessed using characterization techniques involving physicochemical parameters and spectral analysis ( FT-IR, UV-Vis and NMR (1H NMR and 13C NMR) to confirm their synthenses and structures. Additionally, pl-dtc crystals which grew from the pl-dtc solution when refrigerated after five days, has its structure confirmed and revealed when subjected to single crystal x-ray crystallography technique. Differences in results of spectral analysis between ligands and their respective coordination compounds confirmed the coordination between ligands and coordination compounds. The in vitro antibacterial studies showed that the ligands had modest activity against Gram positive bacteria: Staphylococcus aureus, while, the coordination compounds had modest activities against the Gram negative bacteria: Escherichia coli when compared with ligand of pl-dtc.

Pigments are chemical compounds that impart color to materials via absorption, reflection, and refraction. Traditional sources of natural pigments include plant and insect tissues; however, microorganisms such as bacteria, yeasts, algae, and filamentous fungi also hold potential for pigment production. In this study, we investigated pigment production in 20 isolates from our in-house Actinobacteria strain collection, obtained from the banks of the Guaviare and Arauca Rivers in Colombia. Isolates were identified using 16S rRNA gene sequencing. We evaluated different culture media and determined their various bioactivities, including antioxidant, antibacterial, and cytotoxic properties. Promising pigmented hydroalcoholic extracts exhibiting the above-mentioned properties were identified and their chemical compositions were examined using LC-MS. Our findings highlighted a growth medium-dependent effect, as pigment production, coloration, and bioactivity outcomes were influenced by growth media. These results demonstrate the significant potential of Streptomyces isolates as sources of bioactive pigments for diverse applications.

: Since the COVID-19 pandemic, people have become aware that materials (products) can transmit infection and have begun to focus on questions such as how bacteria and germs, the sources of in-fection, maintain their infectivity on material surfaces, and the extent to which materials can or cannot prevent this. and to what extent materials can and cannot prevent it. The SIAA, a non-profit organization of many Japanese companies, had created an entirely separate interna-tional standard for materials' antibacterial, antiviral, and antibiofilm properties (products). The authors have studied the academic basis for the operation of the standards and were deeply in-volved as researchers in establishing one of the standards. This paper describes the interna-tional standards and some representative examples of the authors' actual use of these standards and explains the current status and future problems.

Products derived from Cannabis sativa have gained increased interest and popularity. As these products become common amongst the public, the heath and potential therapeutic values associated with hemp have become a premier focus of research. While the psychoactive and medicinal properties of Cannabis products have been extensively highlighted in literature, the antibacterial properties of CBD have not been explored in depth. This research serves to examine the antibacterial potential of CBD against Salmonella newington and Salmonella typhimurium. In this study we observed bacterial response to CBD exposure through biological assays, bacterial kinetics, and fluorescence microscopy. Additionally, comparative studies between CBD and ampicillin were conducted against Salmonella typhimurium and Salmonella newington to determine comparative efficacy. Furthermore, we observed potential resistance development of our Salmonella spp. against CBD treatment.

Antibiotic resistance was described soon discovery of penicillin by Fleming. In recent years, there has been increasing research interest in the development of alternatives to address this problem. Natural products, mainly, have long been considered as sources of drugs, and a great part of pharmaceuticals available in modern medicine are directly or indirectly derived from natural sources. propolis been used to treat human diseases since ancient times, propolis, is a natural resinous mixture produced by honeybees (Apis mellifera) from collected parts of plants, he is increasingly recognized by their wide range of biological and pharmacological properties, As anti- infective agent, combination synergy with standard antibiotics could be very promising alternative strategy

Hydrogel antibacterial agent is an ideal antibacterial material because of it could diffuses antibacterial molecules into the decayed area by providing a suitable microenvironment and the hydrogel acts as a protective barrier on the decay interface. The biocompatibility and biodegradation make the removal process easily which were widely used in medical fields. However, there have been few reports on its application for controlling postharvest diseases in fruit. In this study, the Chitosan-Ag (CS-Ag) complex hydrogels were prepared using the physical crosslinking method, which used for controlling postharvest diseases in grape. The prepared hydrogels were stable for a long period at room temperature. The structure and surface morphology of CS-Ag composite hydrogels were characterized by UV-Vis, FTIR, SEM, and XRD. The inhibitory effects of CS-Ag hydrogel on disease in grape caused by P. expansum, A. niger and B. cinerea were investigated both in vivo and in vitro. The remarkable antibacterial activity of CS-Ag hydrogels was mainly due to the synergistic antibacterial and antioxidant effects of CS and Ag. Preservation test showed that the CS-Ag hydrogel had positive fresh-keeping effect. This revealed CS-Ag hydrogels plays a critical role in controlling fungal disease in grape.

With the increased scientific interest in green technologies, many researches have been focused on the production of polymeric composites containing naturally occurring reinforcing particles. Apart from increasing mechanical properties, these additions can have a wide range of interesting effects, such as increasing the resistance to bacterial and fungal colonization. In this work, different amounts of two different natural products, namely neem and turmeric, have been added to polyethylene to act as a natural antibacterial and antifungal product for food packaging applications. Microscopic and spectroscopic characterization showed that fractions up to 5% of these products can be dispersed into low-molecular weight polyethylene, while higher amounts could not be properly dispersed and resulted in an inhomogeneous, fragile composite. In vitro testing conducted with Escherichia coli, Staphylococcus aureus and Candida albicans showed a reduced proliferation of pathogens when compared to the polyethylene references. In particular, turmeric, resulted to be more effective against E. coli when compared to neem, while they had similar performances against S. aureus. Against C. albicans, only neem was able to show a good antifungal behavior, at high concentrations. Tensile testing showed that the addition of reinforcing particles reduces the mechanical properties of polyethylene, and, in the case of turmeric, it is further reduced by UV irradiation.

Wearing masks to protect against communicable diseases is an effective tool used in many countries affected by the COVID-19 pandemic. Antibacterial activity, antibacterial efficiency, microbial purity and breathability properties of medical disposable masks are very important. Ag is most commonly applied to antimicrobial textiles, but several studies are known about Ag nano-particles. In this work three antimicrobial additives were used. One of them Rudolf GmBH's RUCO-BAC AGP with silver chloride (AgCl) active ingredient also has antimicrobial activity. Four compositions of the binders with antimicrobial additives were prepared and applied to one-layer nonwoven PP material using screen printing, knife over roll coating and laminating machine methods. The influence of the binder antimicrobial polymer coating on the breathability and antibacterial activity of the nonwoven PP material was evaluated. Results had showed that the composition of the polyacrylic acid binder Tubicoat Thickener LP had the least effect on their breathability and samples with the RUCO-BAC AGP formulation had showed the best antimicrobial response. Therefore, further studies of the antimicrobial coating composition were performed using the binder Tubicoat Thickener LP and antimicrobial additives of different chemical nature and concentration - RUCO-BAC AGP, BI-OME AM10 and Nano Ag aqueous dispersion. Based on the microbiological and air permeability results of the samples of the one-layer nonwoven material with coating, the samples of two-layers and three-layers of medical mask model were prepared. Microbiological studies have shown that three-layered medical mask model with RUCO-BAC AGP composition in the middle layer, in both sides of the model has antibacterial efficiency against three pathogens (E. Coli, K. Pneumoniae, an S. Aureus). The performance of this medical mask model has been found to meet requirements for type I medical masks according to the EN 14863 standard. Study have shown that the microbial purity of the mask model is CFU/g <3.

Compounds of natural origin found in varying quantities in plant-based products constitute a highly significant category, possessing structural significance as well as the capacity to regulate oxidative processes. The activity of these compounds may be modulated by the composition of the biological milieu in which they operate, the pH of the environment, or the presence of metal cations in plants or plant extracts. This work shows the synthetic methodology and the optimization process that took place to synthesize a catechin-copper complex which demonstrated antioxidant activity tested for iron chelation ability, hydroxyl radical test and inhibition of lipoxygenase (15-LOX) activity. Antidiabetic assay was performed by determination of the alpha-amylase and alpha-glucosidase inhibition assays and the antibacterial activity showed results against Staphylococcus aureus and Candida albicans. The complex was characterized by FT-IR, UV-VIS and EDX techniques and the biological activity assays were tested in triplicate to fully confirm the activity.

The rise of antibiotic-resistant strains demands new alternatives in antibacterial treatments. Bacteriophages, with their precise host specificity and ability to target and eliminate bacteria safely, present a valuable option. Meanwhile, hydrogels, known for their excellent biodegradability and biocompatibility, serve as ideal carriers for bacteriophages. The combination of bacteriophages and hydrogels ensures heightened phage activity, concentration, controlled release, and strong antibacterial properties, making it a promising avenue for antibacterial treatment. This article provides a comprehensive review of different cross-linking methods for phage hydrogels and focuses on their application in treating infections caused by various drug-resistant bacteria.

The antimicrobial peptide LRGG (LLRLLRRGGRRLLRLL-NH2) was designed and chemically synthesized in a study conducted by Jia et al. Gram-negative bacteria were found to be sensitive to LRGG and exhibited a high therapeutic index. Genetic engineering methods were used to create the prokaryotic fusion expression vector pQE-GFP-LRGG, and the resulting corresponding fusion protein GFP-LRGG was subsequently expressed and purified. The precursor GFP was then removed by TEV proteolysis, and pure LRGG was obtained after another round of purification and endotoxin removal. The prokaryotic-expressed antimicrobial peptide LRGG displays a broad-spectrum antibacterial effect on gram-negative bacteria and can eliminate 99.99% of E. coli within 100 minutes at the minimal MIC concentration. Compared to the chemically synthesized LRGG, the prokaryotic-expressed LRGG exhibits similar temperature, pH, salt ion, serum stability, and cell selectivity. Furthermore, prokaryotic-expressed LRGG showed excellent therapeutic effects in both the infection model of cell selectivity and no embryotoxicity in a Galleria mellonella infection model. The mechanism by which LRGG causes bacterial death was found to be disruption of Gram-negative cell membrane.

Abstract: Given the increasing resistance of some bacterial strains to many common antibiotics used in the local market, the current study aimed to produce nanoscale particles capable of combating pathogenic bacteria that have developed resistance to current antibiotics. In this research, an ex-perimental study was conducted to produce nanoscale particles using the single-celled blue-green algae Synechococcus sp., which was isolated from a local environment in the Arab Republic of Egypt, specifically from a soil sample in Beni-Suef City. The aim of the study was to generate silver NPs employing different biological approaches, encompassing the direct strain powder technique, ethanol extract pellet technique, and ethanol extract technique. These synthesized nanoparticles displayed different shapes, including cubic, spherical, pellet-like, and rod-shaped particles. They were characterized by bio-functional groups containing Ag+ ions, which were detected using FT-IR, Zeta sizer, and Zeta potential measurements. High-resolution SEM imaging unveiled the mor-phological features of Silver NPs with biologically formed protective layers, spanning sizes from 20 to 430 nm for individual particles. The study evaluated the antibacterial efficiency against both G+ve and G-ve bacteria. The ethanolic extract technique exhibited the largest inhibition zone (24 mm) against G+ve bacteria, particularly Staphy. aureus. Furthermore, it was observed that the larger particles produced using the powder and pellet techniques were less effective antibacterial agents. In conclusion, this investigation emphasizes the potential of cyanobacteria-based synthesis of silver nanoparticles as a promising approach for producing innovative antimicrobial agents.

Classical antibacterial drugs were designed to target specific bacterial properties distinct from host human cells to maximize potency and selectivity. These designs were quite effective as they could be easily derivatized to bear next generation drugs. However, the rapid mutation of bacteria and their associated acquired drug resistance have led to the rise of highly pathogenic superbug bacterial strains for which treatment with first line drugs is no match. More than ever, there is a dire need for antibacterial drug design that goes beyond conventional standards. Taking inspiration by the body’s innate immune response to employ its own supply of labile copper ions in a toxic attack against pathogenic bacteria, which have a very low Cu tolerance, this review article examines the feasibility of Cu-centric strategies for antibacterial preventative and therapeutic applications. Promising results are shown for the use of Cu-containing materials in the hospital setting to minimize patient bacterial infections. Studies directed at disrupting bacterial Cu regulatory pathways elucidate new drug targets that can enable toxic increase of Cu levels and perturb bacterial dependence on iron. Likewise, Cu intracellular chelation/prochelation strategies effectively induce bacterial Cu toxicity. Cu-based small molecules and nanoparticles demonstrate the importance of the Cu ions in their mechanism and display potential synergism with classical drugs.

A single-site, randomized clinical trial was designed to determine the efficacy of regular home use of Lumoral® dual-light antibacterial aPDT in periodontitis patients. For the study, 200 patients are randomized to receive non-surgical periodontal treatment (NSPT), including standardized hygiene instructions and electric toothbrush, and scaling and root planing, or NSPT with adjunctive Lumoral® treatment. A complete clinical intraoral examination is conducted in the beginning, at three months, and at six months. This report presents the three-month results of the first 59 consecutive randomized subjects. At three months, bleeding on probing (BoP) was lower in the NSPT+Lumoral®-group than in the NSPT group (p=0.045), and more patients in the NSPT+Lumoral®-group had their BoP below 10% (52% vs. 29%, respectively, p=0.008). Patients in the NSPT+Lumoral®-group improved their oral hygiene by visible-plaque-index (p=0.0002), while the NSPT group showed no statistical improvement as compared to baseline. Both groups significantly reduced the number of deep periodontal pockets, but more patients with a reduction in their deep pocket number were found in the NSPT+Lumoral® group (92% vs. 63%, p=0.01). Patients whose number of deep pockets was reduced by 50% or more were also more frequent in the NSPT+Lumoral®-group (70% vs. 33%, p=0.01). Patients with initially less than ten deep pockets had fewer deep pockets at three-month follow-up in the Lumoral® group (p=0.02). In conclusion, adjunctive use of Lumoral® in NSPT results in improved treatment outcomes at three months post-therapy.

Implants are used to replace damaged biological structures in human body. Although stain-less-steel (SS) is a well-known implant material, corrosion of SS implants led to the release toxic metallic ions which produce harmful effects in human body. To prevent material degradation and its harmful repercussions, these implanted materials are subjected to biocompatible coatings. Polymeric coatings play a vital role in enhancing the mechanical and biological integrity of the implanted devices. Zein is a natural protein extracted from corn and is known to have good bio-compatibility and biodegradability. In this study, Zein/Ag-Sr doped mesoporous bioactive glass nanoparticles (Ag-Sr MBGNs) were deposited on SS substrates via electrophoretic deposition (EPD) at different parameters. Ag and Sr ions were added to impart antibacterial and osteogenic properties to the coatings, respectively. In order to examine the surface morphology of coatings, optical microscopy and scanning electron microscopy (SEM) were performed. To analyze me-chanical strength, pencil scratch test, bend test, corrosion and wear tests were conducted on ze-in/Ag-Sr doped MBGNs coatings. The results show good adhesion strength, wettability, corro-sion, and wear resistance for zein/Ag-Sr doped MBGNs coatings as compared to bare SS sub-strate. Thus, good mechanical and biological properties were observed for zein/Ag-Sr doped MBGNs coatings. Results suggested these zein/Ag-Sr MBGNs coatings have great potential in bone regeneration applications.

This review focuses on the therapeutic effects of metallic ions when released in physiological environments. Recent studies have shown that metallic ions like Ag+, Sr2+, Mg2+, Mn2+, Cu2+, Ca2+, P+5, etc., have shown promising results in drug delivery systems and regenerative medicine. These metallic ions can be loaded in nanoparticles, mesoporous bioactive glass nanoparticles (MBGNs), hydroxyapatite (HA), calcium phosphates, polymeric coatings, and salt solutions. The metallic ions can exhibit different functions in the physiological environment such as antibacterial, antiviral, anti-cancer, bioactive, biocompatible, and angiogenic effect. Furthermore, the metallic ions can be loaded in scaffolds to improve osteoblast proliferation, differentiation, bone development, fibroblast growth, and improved wound healing efficacy. Moreover, different metallic ions possess different therapeutic limits. Therefore, further mechanisms need to be developed for the highly controlled and sustained release of these ions. This review paper summarizes the recent progress in the use of metallic ions in regenerative medicine and encourages further study of metallic ions as a solution to cure diseases.

Salmonella can cause acute and chronic infections in humans. Salmonella species are known to cause food poisoning and other diseases in developing countries. Their role in the pathogenesis of these diseases has received increased international attention. Despite numerous advances in sanitation, they still can infect humans and cause outbreaks in developed countries. For example, Salmonella causes about 1.2 million illnesses in the US each year with over 450 deaths. Additionally, Salmonella outbreaks cause significant losses to chicken producers globally. The Salmonella species is also prone to acquiring resistance to various classes of antibiotics. Hence, the need for a paradigm shift from antibiotics to bacteriophages to manage, control and treat bacterial infections. The ɛ34 phage belongs to Podoviruses and categorized into the P22-like phages. The P22-like phages include ɛ34, ES18, P22, ST104, and ST64T. In this work, we investigated the antibacterial property of ɛ34 phage tailspike protein against Salmonella newington (S. newington). We demonstrate here that, the phage’s tailspike protein enzymatic property as a LPS hydrolase synergizes with Vero Cell culture supernatant in killing S. newington. Using decellularized cartilage scaffold as an ex vivo tissue model, the ɛ34 TSP protected the scaffold from S. newington biofilm formation. Computational analysis of the ɛ34 TSP interaction with membrane proteins of S. newington demonstrated a higher probability (0.7318) of binding to ompA of S. newington, and when docked to ompA extracellular component, it produced a high free energy of -11.3kcal/mol. We also demonstrate the resistance/sensitivity of the tailspike to the digestive enzyme trypsin. The data obtained in this work indicates that the trypsin resistant tailspike protein of Ɛ34 phage can be formulated as a novel antibacterial agent against S. newington.

Microbial infections in wounds can significantly delay the healing process, with bacteria often forming protective biofilms that shield them from external threats. In this study, we evaluated the impact of copper oxide-impregnated wound dressings (referred to as COD) on a bacterial mixture comprising common gram-positive and gram-negative wound pathogens encased in biofilm. The bacterial mix was exposed to COD or control dressings for 0, 1, 2, and 3 hours, and the effects were analyzed using scanning electron microscopy. After just 1 hour of exposure to COD, notable leakage of bacterial cytoplasmic contents was observed. By the 3-hour mark, the gram-negative bacteria exhibited formation of holes in their cell walls, while gram-positive bacteria showed a reduction in cell width. These findings demonstrate the ability of COD to effectively kill bacteria, even when protected by biofilm, supporting clinical observations of its efficacy in managing infected wounds.

Self-healing, stretchable and moldable hydrogels have a great potential application in tissue engineering and soft robotics. Despite great success in reported hydrogels, it is still a great challenge to construct the moldable hydrogels with an ultrafast self-healing performance. Herein, the dynamic double network (DN) composite hydrogels (PBLH) with ultrafast self-healing, stretchable and moldable were successfully constructed by poly (vinyl alcohol) (PVA), borate, ε-poly-L-lysine (EPL) and hyaluronic acid (HA) based on an efficient one-pot method. Fourier transform infrared spectroscopy, X-Ray diffraction and rheological measurements confirmed the formation of dynamic double networks among PVA, B, EPL and HA through the cross-linking of dynamic borate bonds, electrostatic interaction and hydrogen bonding. Having fabricated the dynamic double network structure, the damage gap of the composite hydrogels can heal within 1 min, presenting an excellent self-healing ability. Simultaneously, the DN hydrogels can be molded to various shapes and the length of the DN hydrogels can be stretched to 15 times than original length. In addition, the DN hydrogels exhibited an excellent antibacterial property against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Our results illustrated that the DN composite hydrogels not only retain the advantages of traditional hydrogels, but also possess ultrafast self-healing, outstanding stretchable and antibacterial properties, presenting a prospective candidate for constructing biomedical materials.

In this study electrophoretic deposition (EPD) technique is used to prepare chitosan-based coatings with enhanced antibacterial activity suitable for bone implants applications. We designed, prepared and compared physic-chemical and biological properties of coatings obtained with commercial chitosan, chitosan enriched with silver nanoparticles and chitosan obtained from insects. With the aim to consider the sustainability issue, silver nanoparticles were directly prepared in the chitosan solution by laser ablation in liquid technique, avoiding the use of chemicals and limiting the production of wastes. Moreover, a sustainable source of chitosan such as Hermetia Illucens exuviae was considered. The EPD process was optimized by adjusting parameters like voltage and deposition time to achieve ideal coating thickness and adhesion. The prepared films were characterized by spectroscopic and microscopic techniques such as SEM, XRD, and FTIR. Antimicrobial tests against E. coli and S. aureus revealed that silver nanoparticles enhanced the antibacterial properties of the polymer, whereas biological evaluation using the WST8 test on MG63 human osteoblasts-like cells showed that all coatings are non-toxic. Finally, chitosan obtained from insect showed comparable properties with respect to the commercial polymer, suggesting it could replace seafood-derived chitosan in biomedical applications, whereas the Ag@chitosan composite demonstrated superior antibacterial activity without compromising its biocompatibility.

Abstract: A. baumannii exhibits resilience in harsh environments and progressively develops resistance to diverse antibacterial agents over time. This adaptability poses a significant challenge in treating an infection caused by this bacterium within healthcare settings. The presence of peptidoglycan, a crucial precursor for cell wall synthesis, contributes to this challenge. Peptidoglycan serves not only as a structural support in bacterial cells but also provides protection against adverse environmental conditions. The synthesis of the peptidoglycan layer involves a group of substrates such as N-acetylglucosamine (GlcNAc) and N-acetylmuramic acid (MurNAc), within a three-partitioned process occurring in the membrane, periplasmic space, and cytoplasm of each bacterium. Initiated in the cytoplasm and extending to the inner cell membrane, this synthesis starts with the production of nucleotide precursors. The first step involves the synthesis of UDP-GlcNAc, orchestrated by Glm (GlmS, GlmM, and GlmU) enzymes using fructose-6-phosphate. Subsequently, enzymes from the Mur family, namely MurB, MurA, MurD, MurC, MurI, MurF, and MurE, synthesize UDP-N-acetylmuramyl-pentapeptide (UDP-Mpp) from UDP-GlcNAc. Concurrently, on the cytosolic side, the production of membrane-surrounded undecaprenyl phosphate occurs, involving membrane-side proteins MraY and MurG in the biosynthesis of peptidoglycan. This review emphasizes updated information on Mur family proteins, encompassing physicochemical properties, nature of binding site, number and type of binding site residues, functional domain details, three-dimensional structural aspects, and their functions within bacterial cells. Special attention is directed towards their enzymatic role in peptidoglycan biosynthesis due to the limited availability of precursors in the market. Additionally, the review provides a comprehensive summary of existing inhibitors and ongoing efforts in identifying new targeted inhibitors, recognizing these enzymes as potential candidates for antibacterial drug design and discovery.

To reveal the antibacterial effect of wound secretions of different Chinese fir strains on five kinds of bacteria. Three 3-year-old seedlings of Taxus chinensis var.koraiensis and Yangkou and the 3-year-old container seedlings of Taxus chinensis var.pendula, Yang061 and Yang020, were used as the research objects. The antibacterial effect of wound secretions was determined by the filter paper diffusion method, and the antibacterial effect was analyzed. Results showed that the wound secretions of different strains of Chinese fir bark had noticeable bacteriostatic effects on Bacillus subtilis, Salmonella paratyphi B, Pseudomonas aeruginosa, Escherichia coli, and Staphylococcus aureus. However, the bacteriostatic effects of different strains of Chinese fir secretions differed. The minimum inhibitory concentrations (MICs) of the wound secretions of different strains of Chinese fir against the five test bacteria differed. The mean MIC of Pseudomonas aeruginosa was the highest, and the mean MIC of Escherichia coli was the lowest. The antibacterial ability of the wound secretions of different Chinese fir strains was mainly determined by the composition of the wound secretions. There was no noticeable relationship with the number of wound secretions.

At this time, nanoparticles used to been considered for various biomedical applications due to their particular properties[1, 2]. It is already known that one of the major advances in the relative application of nanoparticles is the recognition of the steric stabilization which can increase the particle stability in the biological environment and provide the opportunities of the application of nanoparticles in the development of drug delivery systems (DDSs) for achieving drug targeting and controlled drug release. Nano crystalline silver particles (AgNPs) have major applications in biomolecular recognition of highly sensitive, anti-microbial treatment, catalysis and manufacture sensors [3-7]. The NPs for various applications medical like image quality, medicine, tissue, magnetic resonance imaging (MRI) of targeting tissues and cells styles. This is particularly the case of AgNPs significantly encompasses the whole a wide range of industrial and medical applications. In this study, we have been synthesized incorporated omeprazole and omeprazole sulfide drugs with AgNPs and the results was investigated with TEM, FT-IR, DRS and XRD. The particle size has been seen in imaging TEM about 80 nm. Moreover either Omeprazole@AgNPs or omeprazole sulfide@AgNPs are able to excrete bacteria. In this study, the antibacterial properties of drugs with silver nanoparticles also increased.

By slowly evaporating 4-bromo-2-methylbenzonitrile at room temperature, it was possible to make a single organic nonlinear optical crystal. The grown crystal's crystalline nature was verified, and the unit cell characteristics are provided as a = 4.08Å, b = 6.61 Å, c = 28.93Å, α = 90º, β = 90º, γ = 90º. The functional groups of the crystal produced were identified using the FTIR and FT-Raman spectra. The UV cutoff wavelength is found at 221.6 nm, and the transparency nature of the crystal was analyzed in the optical studies.  The band gap of the grown crystal was estimated using the Taucs’ plot. The violet and red emissions of photoluminescence are discussed. A high dielectric constant was received at a low frequency. The TG/DTA curve shows that the grown crystal was stable up to 125.59 ºC.  The Kurtz-Perry powder technique was applied to confirm the Second Harmonic Generation's (SHG) nature. By using the agar diffusion method, the antibacterial property of the grown 4B2MBN crystal was determined.

Background: The use of nitinol (NiTi) archwires in orthodontic treatment has expanded significantly due to unique mechanical properties. The greatest barrier to safe orthodontic treatment is chemically or microbiologically induced corrosion, resulting in Ni2+ release. The aim of this investigation was to enhance corrosion resistance and introduction antibacterial properties to NiTi archwire by coating them with TiN-Cu. Methods: NiTi archwires were coated with TiN-Cu using cathodic arc evaporation and direct current magnetron sputtering. The morphology of the sample was analyzed by FESEM and the chemical composition was assessed using EDS, XRD and FTIR. Inductively coupled plasma-optical emission spectrometry was used to estimate the ion release. Biocompatibility of samples was investigated using MTT test. Antibacterial activity was analyzed against Streptococcus mutans and Streptococcus mitis. Results: Physico-chemical characterization revealed well-designed coatings with the presence of TiN phase with incorporated Cu2+. TiN-Cu coated archwires showed statistically lower Ni2+ release (p<0.05). Relative cell viability was the highest regarding 28-day eluates of TiN-Cu coated archwires (p<0.05). The most remarkable decrease in Streptococcus mitis concentrations was observed in case of TiN-Cu coated archwires (p<0.05). Conclusion: Taking into account biocompatibility and antibacterial tests, TiN-Cu coated archwires may be considered as a good candidate further clinical investigations.

Chemical investigation of the Chinese soft coral Lobophytum sp. has resulted in the isolation of six new compounds, namely lobosteroids A–F (1–6), along with four known compounds. Their structures were determined by extensive spectroscopic analysis and comparison with the spectral data reported in the literature. Among them, the absolute configuration of 1 was determined by X-ray diffraction analysis. These steroids characterized by either the presence of an α,β-αꞌ,βꞌ-unsaturated carbonyl or an α,β-unsaturated carbonyl moiety in ring A, or the existence of a 5α,8α-epidioxy system in ring B, as well as diverse oxidation sites of side chains. The prelimi-nary antibacterial bioassay showed all compounds exhibited significant antibacterial activities against the fish pathogenic bacteria Streptococcus parauberis FP KSP28 and Phoyobacterium damselae FP2244 with all inhibition rates more than 90% at the concentration of 150 µM. And at the same concentration, compounds 2, 6–10 also displayed potent inhibitory effects against vancomy-cin-resistant Enterococcus faecium bacteria G7 with all inhibition rates more than 90%.

Copper oxide nanoparticles (CuONPs) were synthesized using an eco-friendly method and their antimicrobial and biocompatibility properties were determined. The supernatant and extract of the fungus Ganoderma sessile yielded small, quasi-spherical NPs with an average size of 4.5 ± 1.9 nm and 5.2 ± 2.1 nm, respectively. CuONPs showed antimicrobial activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. Minimum inhibitory concentration (MIC) for E. coli and S. aureus was 15.9 µg/mL for nanoparticles (NPs) using the supernatant (CuONPs-S) and 16.5 µg/ml for NPs using the extract (CuONPs-E). Lower concentrations were required for P. aeruginosa inhibition. Ultrastructural analysis revealed the presence of the small CuONPs all through the bacterial cells. Finally, the toxicity of CuONPs was analyzed in three mammalian cell lines: hepatocytes (AML-12), macrophages (RAW 264.7) and kidney (MDCK). Low concentrations (<15 µg/ml) of CuONPs-E were non-toxic to kidney cells and macrophages, and the hepatocytes were the most susceptible to CuONPs-S. The results obtained suggest that the CuONPs synthesized using the extract of the fungus G. sessile, could be further evaluated for the treatment of superficial infectious diseases.

Introduction: Among the many factors that may limit effective wound healing in patients with chronic ulcers, bacterial infection and poor cell recruitment are primary causes that contribute to prolonged healing. Thus, a novel strategy that aims to prevent bacterial infection within the wound, while at the same time providing structural scaffolding that promotes endogenous tissue repair, would be of great interest. Here, we developed a thermo-sensitive silver nanoparticle hydrogel composite as an antibacterial nutritional scaffold for the wound that contains all nutrients required for cell growth while preventing bacterial infection with the ability to fill up all the cavities and void areas in wounds regardless of their geometry. Methods: Silver nanoparticles (AgNPs) were synthesized by chemical reduction. After characterization, silver hydrogel nanocomposite was developed by reconstitution of collagen-based hydrogel powder in a nanoparticle suspension of varying AgNPs concentrations (200, 400, and 600 ppm). The antibacterial activity of the formulations was examined in vitro and in vivo in subcutaneous implant infected model. The wound healing efficacy of the hydrogel nanocomposite was also evaluated using a splinted wound model in rats through comparison of clinical wound measurements and histological assessments. Cytocompatibility assay and biochemical analysis of blood at the end of in vivo wound healing study were performed to evaluate the safety of formulations. Results: The synthesized nanoparticles were spherical and stable. While hydrogel alone did not show any bacterial reduction in vitro, the inhibition of bacterial growth was significant in all silver hydrogel nanocomposites compared to controls (p <0.05) and was dose-dependent, with maximum reduction observed in the 600 ppm group (4.56±0.26 LOG CFU/mL, P<0.001). All concentrations of AgNPs hydrogel composites showed significant antibacterial activity in vivo as well (P<0.0001). Treatment of splinted wounds with AgNPs hydrogel composite resulted in faster wound closure and accelerated wound re-epithelialization. The formulations were non-cytotoxic and did not differ significantly in hematological and biochemical factors from the control group in in vivo study. Conclusions: By presenting promising antibacterial and wound healing activity, silver hydrogel nanocomposite offers a safe therapeutic option that can be used as a functional scaffold for an acceleration of wound healing.

Over the years, chitosan has been the subject of numerous studies and has gained significant popularity as a biomaterial due to its various characteristics, including biocompatibility, biodegradability, and bioactivity. In this work, chitosan fibres surface was modified with ursolic acid to improve their antibacterial properties by wet impregnation method. Five specimens of chitosan fibres were immersed in ursolic acid (UA) solution for varying immersion times of 1, 2, 4, 6, and 8 hours. Characterization was carried out by means of FTIR, SEM, UV-Vis spectroscopy; the results indicated an ongoing chemical reaction between chitosan and ursolic acid resulting in changes to the chemical structure. After 2 hours, the absorbance ratio remained constant; suggesting that the reaction had reached completion and the chemical structure of the sample remained stable. Antibacterial tests were performed on the resulting chitosan fibres against two bacterial strains. The fibres without ursolic acid did not exhibit any noteworthy antibacterial activity against either strain. However, the chitosan fibres modified with ursolic acid showed significant and almost strong antibacterial activity against the Gram-positive strain, S. aureus. These results suggest that chitosan fibres modified with ursolic acid could have potential applications as antibacterial materials, particularly against Gram-positive bacteria.

Jade waste is a normal byproduct that makes up much more than the amount of jade extracted. Therefore, recycling jade waste is worth investigating from the point of view of energy conservation. Moreover, it is an environment-friendly material, which is desirable for use in building materials. In this study, Xiuyan jade waste was repurposed as antibacterial additives for building coatings. The powder waste was activated by milling and subsequent annealing. The antibacterial properties of the treated waste were mostly related to the annealing temperatures. Based on the investigations of the phase change and the release of metal ions of a series of samples and their antibacterial activities, the antibacterial mechanism of the treated samples was explored experimentally. The most applicable sample for coatings was finally chosen by considering its pH values and its antibacterial abilities. Antibacterial testing showed that the addition of treated jade waste could enhance the bacterial inhibition rate of building coatings from 60% to 99.9%.

Biocidal compositions based on interpolyelectrolyte complexes and a low molecular weight antibiotic can become a promising material for creating biocidal coatings, as they combine wash-off resistance and dual biocidal action due to the biocide and the polycation. Molecular mass characteristics of polymers play essential role in physics and mechanical properties of the coatings. In this work, the properties of polydiallyldimethylammonium chloride (PDADMAC) coatings of various molecular weights are investigated and assumptions are made about the optimal molecular weight needed to create antibacterial compositions. To study the resistance to washing off and moisture saturation of the coatings, the gravimetric method was used, the adhesive properties of the coatings were studied by dynamometry. It has been established that an increase in molecular weight affects the wash-off resistance of coatings, but does not affect moisture absorption and adhesion mechanics of coatings. All samples of PDADMAC were demonstrated to exhibit the same antibacterial activity. Thus, when developing systems for creating antibacterial coatings, it must be taken into account that in order to create stable coatings. The requirement to use PDADMAC with a high degree of polymerization is necessary for control the desorption of coating during wash off-but not mandatory for the control of mechanical and antibacterial properties of the coating.

Reaction of 2-mercapto-3-phenylquinazolin-4(3H)-one (MPQ) with both 4-vinyl benzyl chloride and allyl bromide furnished the reactive heterocyclic monomers 3-phenyl-2-((4-vinylbenzyl) thio) quinazolin-4(3H)-one (PVTQ) and 2-(allylthio)-3-phenylquinazolin-4(3H)-one (APQ), respectively. Copolymerization of PVTQ monomer with styrene and methyl methacrylate in the presence of 2,2′-azobisisobutyronitrile (AIBN) afforded the copolymers PS-co-PPVTQ and PMMA-co-PPVTQ, respectively. Similarly, copolymerization of monomer APQ with styrene and methyl methacrylate (MMA) afforded the copolymers PS-co-PAPQ and PMMA-co-PAPQ, respectively. The resulted copolymers were characterized by using FT-IR, 1H-NMR and GPC techniques. Silver nanocomposites of PS, PMMA, PS-co-PPVTQ, PMMA-co-PPVTQ, PS-co-PAPQ and PMMA-co-PAPQ were synthesized by the addition of silver nitrate into the polymer solution. The reduction of silver ions into silver nanoparticles was performed in DMF and water. Thermogravimetric (TGA) analysis was used to determine the thermal stability of the copolymers and their silver nanocomposites. The X-ray diffraction (XRD) analysis indicated the amorphous structures of the co-polymers and confirmed the formation of silver nanoparticles. The antitumor and antibacterial activities were screened for the copolymers and enhanced by the formation of their silver nanocomposites. In vivo antitumor activity in Ehrlich Ascitic Carcinoma (EAC) mice model showed that PS-co-PPVTQ/Ag NPs, PMMA-co-PPVTQ/Ag NPs, and PMMA-co-PAPQ/Ag NPs displayed promising inhibitory effects against EAC and induce apoptosis against MCF-7 cells.

A sequence of new acetamide derivatives 9-15 of primary, secondary amine, and para-toluene sulphinate sodium salt have been synthesized under microwave irradiation and assessed in vitro for their antibacterial activity against one Gram-positive and two Gram-negative bacterial species such as S. pyogenes, E. coli, and P.mirabilis using the Mueller-Hinton Agar diffusion (well diffusion) method. The synthesized compounds with significant differences in inhibition diameters and MICs were compared with those of amoxicillin, ampicillin, cephalothin, azithromycin and doxycycline. All of the evaluated acetamide derivatives were used with varying inhibition concentrations of 6.25, 12.5, 37.5, 62.5, 87.5, 112.5 and 125 µg/ml. The results show that the most important antibacterial properties exercised by the synthetic compounds 9 and 11 bearing para-chlorophenyl moiety incorporated into the 2-position moiety of acetamide 2. The molecular structures of the new compounds were determined using FT-IR, 1H-NMR techniques.

Pectin extracted via hydrodynamic cavitation in water only from waste lemon peel and further isolated via freeze drying displays significant antibacterial activity against Staphylococcus aureus, a Gram positive pathogen which easily contaminates food. The antibacterial effect of the new IntegroPectin is largely superior to that of commercial citrus pectin, opening the way to advanced applications of a new bioproduct now obtainable in large amounts and at low cost from citrus juice industry’s waste.

Natural products are an important source of antibacterial agents. Canthin-6-one alkaloids have displayed potential antibacterial activity based on our previous work. In order to improve the activity, twenty-two new 3-N-benzylated 10-methoxy canthin-6-ones were designed and synthesized through quaternization reaction. The in vitro antibacterial activity against three bacteria was evaluated by double dilution method. Four compounds (6f, 6i, 6p and 6t) displayed 2-fold superiority (minimum inhibitory concentration (MIC) = 3.91 µg/mL) against agricultural pathogenic bacteria R. solanacearum and P. syringae than agrochemical propineb. Moreover, the structure–activity relationships (SARs) were also carefully summarized in order to guide the development of antibacterial canthin-6-one agents.

We report the production of metal oxide (TiFe₂O₄, ZnFe₂O₄) nanoparticles by pulsed laser ablation technique in liquid environment. We used nano second Nd: YAG laser systems working at 532 nm and 1064 nm of wavelength, the energy of the laser beam was kept constant at 80 mJ. Absorbance spectra, surface plasmon resonance, optical band-gap and nanoparticle morphology were investigated using ultraviolet-visible (UV-Vis) spectroscopy, Fourier transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). Changing the wavelength of the laser for growth, nanoparticles shown shift between the absorbance and surface plasmon resonance peaks in their UV-Vis spectra, this implies that the optical properties of the colloid nanoparticles depends on laser parameters, this was confirmed with the variation of the band gap energy. Furthermore, red shift for the absorbance peak was observed for samples as-growth at 532 nm around the 150 nm as function of time preparation. Whereas, for the samples as-growth at 1064 nm there is no shift in the absorbance spectra, this can be due to agglomeration and formation of larger particles. The characterization results shown appropriate plasmonic photo-catalysts properties of the particles, hence the photo activation of the nanoparticles was examined on antibacterial effect using colonies of Staphylococcus Aureus and Escherichia coli.

Bacterial resistance towards existing class of antibacterial drugs continues to increase posing significant threat to clinical usefulness of these drugs. This increasing and alarming rates of antibacterial resistance development and the decline in the number of new antibacterial drugs approval continue to serve as major impetus for research into discovery and development of new antibacterial agents. We synthesized a series D-/L-alaninyl substituted triazolyl oxazolidinone derivatives and evaluated their antibacterial activity against selected standard Gram-positive and Gram-negative bacterial strains. Overall, the compounds showed moderate to strong antibacterial activity. Compounds 9d and 10d (D- and L-alaninyl derivatives bearing 3,5-dinitrobenzoyl substituent), 10e (D-alaninyl derivative bearing 5-nitrofurancarbonyl group) and 9f and 10f (D- and L-alaninyl derivatives bearing 5-nitrothiophene carbonyl moiety) demonstrated antibacterial activity (MIC:2 g/mL) against S. aureus, S. epidermidis, E. faecalis and M. catarrhalis standard bacterial strains. No significant differences were noticeable between the antibacterial activity of the D- and L-alaninyl derivatives as a result of the stereochemistry of the compounds.

Many wounds are unresponsive to current available treatment techniques and therefore there is an immense need to explore suitable materials including biomaterials, which are being considered as the crucial factor to accelerate the healing cascade. In this study, we fabricated polyhydroxyalkanoate based antibacterial mats via electrospun technique. One-pot green synthesized graphene decorated silver nanoparticles (GAg) were incorporated into the fibres of poly-3 hydroxybutarate-co-12 mol% hydroxyhexanoate (P3HB-co-12mol% HHx), a co-polymer of polyhydroxyalkanoate (PHA) family which is highly biocompatible, biodegradable and flexible in nature. The synthesised PHA/GAg biomaterial was characterized by field emission scanning electron microscopy (FESEM), elemental mapping, thermogravimetric analysis (TGA), UV-visible spectroscopy (UV-vis) and Fourier transform infrared spectroscopy (FTIR). In-vitro antibacterial analysis were performed to investigate the efficacy of PHA/GAg against gram positive Staphylococcus aureus (S.aureus) strain 12600 ATCC and gram negative Escherichia coli (E.coli) strain 8739 ATCC. The results indicated that the PHA/GAg demonstrated significant reduction of Staphylococcus aureus (S.aureus strain 12600 ATCC) and Escherichia coli (E.coli strain 8739 ATCC) as compared to bare PHA or PHA-rGO in 2 hours of time. The P value (P< 0.05) was obtained by using 2 sample T-test distribution.

The present study aims to evaluate the antibacterial activity of five commercially available essential oils (EOs): Lavender (LEO), Clove (CEO), Oregano (OEO), Eucalyptus (EEO), and Peppermint (PEO) against the most-known MDR Gram-positive and Gram-negative bacteria - Staphylococcus aureus (ATCC 25923), Escherichia coli (ATCC 25922) and Pseudomonas aeruginosa (ATCC 27853) - alone and in various combinations. Gas Chromatography-Mass Spectrometry (GC-MS) analysis established their complex composition. Then, the antibacterial activity was investigated in vitro by diffusimetric antibiogram method, using sterile cellulose discs with Ø 6 mm impregnated with 10 µl of sample and sterile borosilicate glass cylinders loaded with 100 µl of sample; MIC (µg/mL) for each EO was calculated from IZD values (mm) measured after 24 hours. The following EO combinations were evaluated: OEO+CEO, CEO+EEO, CEO+PEO, LEO+EEO, and EEO+PEO. Then, the influence of each dual combination on 3 conventional antibacterial drugs – Neomycin (NEO), Tetracycline (TET), and Bacitracin (BAC) - activity was investigated. The most active EOs against S. aureus and E. coli were LEO and OEO (IZD = 40 mm). They were followed by the CEO and EEO (IZD = 20-27 mm); PEO exhibited the lowest antibacterial activity (IZD = 15-20 mm). EEO alone showed the highest inhibitory activity on P. aeruginosa (IZD = 25-35 mm). It was followed by the CEO, LEO, and EEO (IZD = 7-11 mm), while PEO proved no antibacterial action against it (IZD = 0 mm). Only one synergic action was recorded (OEO+CEO against P. aeruginosa); EEO+PEO revealed partial synergism against S. aureus and CEO+PEO additive behavior against E. coli. Two triple associations with TET showed partial synergism against E. coli, and the other 2 ones (with NEO and TET) evidenced the same behavior against S. aureus; all contained EEO+PEO or CEO+PEO. Most combinations reported indifference. However, numerous cases were of antagonism between constituents included in double and triple combinations, and EOs with the strongest antibacterial activities belong to the highest antagonistic combinations. A consistent statistical analysis supports our results, showing that EOs with moderate antibacterial activities could generate combinations with higher inhibitory effects based on synergistic or additive interactions.

A prominent class of reactions, reductive aminations are used extensively in research labs and industry to synthesize amines; which are applied in a variety of medicines, agrochemicals, and biomolecules. Amine compounds are essential in many aspects of life; amino groups exist in many natural and agricultural products. New 4-(benzylamino)benzoic acid derivatives with general formula of C14H12NO2R, where [R= (H), (4-Cl), (4-NMe), (4-Br), (3-NO2), (4-NO2), (2-OMe), (3-OMe), (4-OMe), (2,3-OMe), (3,4-OMe), (2-OH, 3-OMe), (3-OMe, 4-OH), (3,5-OMe, 4-OH), (2-OH, 5-Br), (3-OH), (4-SMe), (2,3-OH), (3-CF3)] (compounds 1-19) were obtained by reductive amination reaction via reacting p-amino benzoic acid with benzaldehyde derivatives and sodium borohydride. All prepared compounds has been characterized by a variety of spectroscopic techniques (HRMS, FT-IR, 1H, and 13C{1H} NMR) and elemental analysis. Furthermore, the structure of some of the synthesized derivatives were confirmed by single crystal X-ray diffraction (R = 4-Cl, 4-Br, 2-OMe, 3-OMe, 4-OMe, 2,3-OMe), compounds 2, 4, 7-9 and 11, respectively. Moreover, some of these new compounds have shown somehow moderate antibacterial activities against different strains of bacteria (gram-positive and gram-negative) with MIC values ranging from 64-256 µg/ mL. The anticancer activities of all compounds (IC50 values, µM) were evaluated against different cell lines, HGF (Fibroblasts; normal cell line), A549 (Non-Small Cell Lung Cancer cell line) and H69 (Small Cell Lung Cancer cell line). Compound 18 showed a considerable IC50 value of 90.69 against A549 and an excellent value of 32.22 and H69, respectively.

Treatment with herbal medicine continues to enjoy widespread popularity not only in the developing world, because of low costs, easy availability, and low risk of adverse effects. One such plant is Curcumin longa L., or turmeric, which has a long history of both culinary and medicinal uses throughout Asia, spanning thousands of years. In addition to traditionally being used as a dye, as a flavouring and colouring agent in foods, and, e.g., marriage rituals, turmeric is also notable for its long history of use to treat a variety of medical conditions, including inflammatory, bacterial, and fungal diseases and infections, jaundice, tumours, and ulcers among others. In light of this long history of use, it is not surprising to find that also modern biochemistry and clinical research studies show that a significant component of turmeric, curcumin, may have a multitude of therapeutic benefits, much of it attributed to the herb’s antioxidant qualities which are crucial for the prevention and treatment of, e.g., chronic inflammatory illnesses, conditions that often act as precursors for other serious diseases, including cancer and neurological disorders, such as Parkinsons and Alzheimer’s. Furthermore, investigations on the safety profile and toxicity of curcumin have shown that it is generally safe even at large dosages, although caution is necessary as curcumin also have documented anticoagulant effects. This article is focused on providing a better perspective into molecular mechanisms for possible actions along with an in-depth review of recent studies of curcumin, its beneficial role and therapeutic applications in chronic health conditions, with a focus on its cancer, inflammatory bowel disease, osteoarthritis, atherosclerosis, peptic ulcer, Covid19, psoriasis, vitiligo, and depression.

Recent studies have suggested significant antimicrobial properties of some metallic nanoparticles during the height of antibiotic resistance. The silver nanoparticle (AgNPs) is one of the most prominent candidates due to its noble nature and better tolerance profile in humans. The synthesis of AgNPs was carried out using silver nitrate using five different chemical reduction methods and comparing their activity with silver nitrate, also known to possess antimicrobial properties. AgNPs have been synthesized with varying combination of reducing agents, and subsequently characterized by UV-visible spectroscopy, thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and dynamic light scattering (DLS). Chemical reduction with both trisodium citrate and sodium borohydride provided better particle size and controlled uniformity, whereas hydrogen peroxide was used as a stabilizer to increase the stability of AgNPs. The minimum bactericidal concentration (MBC) for all AgNP formulations was determined against gram-negative E. coli, and AgNPs synthesized with only trisodium citrate were found to be the most effective. The synthesized AgNPs were tested against the resistant strains of E. coli, Salmonella, Klebsiella, Bacillus, and Staphylococcus by the well diffusion method to evaluate and compare their inhibition zones and AgNPs synthesized with polyethylene glycol and polyvinyl pyrrolidine were found to be the most efficient.

Five new cembrane-type diterpenes, lobocalines A–E (1–5), and four new steroids, lobocalines F–I (9–12), along with six known related compounds (6–8 and 13–15) were isolated from the Yalong Bay soft coral Lobophytum catalai. The structures of the new compounds were elucidated by extensive spectroscopic analysis, NMR calculation with DP4+ analysis, time-dependent density functional theory-electronic circular dichroism (TDDFT-ECD) calculations, X-ray diffraction analyses, and the comparison with the reported spectroscopic data of known compounds. Further, with the aid of X-ray diffraction analysis, the structure of lobocrasol B (15) was firmly revised as 15a. In in vitro bioassays, compound 2 showed moderate antibacterial activities against fish pathogenic bacteria Streptococcus parauberis KSP28 and Phoyobacterium damselae FP2244 with minimum inhibitory concentration (MIC) values of 8.7 and 17.3 µg/mL, respectively. All the steroids exhibited antibacterial activities against the S. parauberis KSP28 with MIC values ranging from 12.3 to 53.6 µg/mL. Compounds 2, 7 and 14 have remarkable inhibitory effects on the hemolysin production of Staphylococcus aureus, while compounds 8–12 have medium inhibitory effects on the pyocyanin production in Pseudomonas aeruginosa.

This research focuses on exploring the bioactive and antibacterial properties of extracts from the flowers and bark of four Magnolia species (Magnolia champaca, Magnolia denudata, Magnolia grandiflora, and Magnolia officinalis) for possible cosmetic applications. We used ethanol to extract compounds from these plants and conducted various tests including spectrophotometry, HPLC, GC-MS, and microbiological analyses. The extracts, particularly rich in polyphenols (55.18 mg GAE/g), displayed significant antioxidant capabilities, with IC 50 values ranging between 9.99 mg/mL and 23.23 mg/mL. We quantified different compounds: phenolic acids (6.259 to 27.883 mg/g dry weight), aglycone flavonoids (61.224 to 135.788 mg/g dw), glycosidic flavonoids (17.265 to 57.961 mg/g dw), and lignans (150.071 to 374.902 mg/g dw). We identified 76 volatile compounds, predominantly oxygenated monoterpenes and sesquiterpene hydrocarbons, which contribute to the antibacterial effectiveness of the extracts. These extracts showed greater antibacterial activity against Gram-negative bacteria than Gram-positive bacteria. The diverse chemical compounds and their demonstrated activities suggest these extracts could be valuable in cosmetic, pharmaceutical, or food industries.

Researchers are increasingly focusing on green synthesis methods for silver nanoparticles due to their cost-effectiveness and reduced environmental impact. In this study, we utilized an edible bird's nest (EBN), a valuable economic resource, as the primary material for synthesizing silver nanoparticles using only water as the solvent. Metabolite profiling of the EBN extract was conducted using LC-QTOF-MS in positive mode (ESI+), revealing the presence of lipids, glycosides, peptides, polysaccharides, and disaccharides. Upon the addition of silver nitrate to the aqueous EBN extract, noticeable color changes from transparent to brown indicated the successful formation of AgNPs. Subsequent characterization of these silver nanoparticles involved UV-Visible spectroscopy, which revealed an absorption peak at 421 nm. Further characterization was carried out using Field Effect Scanning Electron Microscopy (FESEM), Attenuated Total Reflectance-Fourier Infrared (ATR-FTIR) spectroscopy, and Energy Dispersive X-Ray (EDX) analysis. The involvement of phenolic agents, proteins, and amino acids in reducing the silver particles was confirmed. The synthesized nanoparticles exhibited a crystalline nature, a spherical shape, and a particle size ranging from 10 to 20 nm. The presence of elemental silver was confirmed by a strong, intense peak around 3 keV in the EDX spectrum. To assess their potential, the antibacterial properties of the silver nanoparticles against Escherichia coli and Staphylococcus aureus were evaluated using the agar diffusion method.

The upsurge in and havoc being wrecked by antibiotic resistant bacteria makes urgent the need for efficacious alternatives to antibiotics. This study assessed the antibacterial efficacy of two isobutyl-cyanoacrylate nanoparticles (iBCA-NPs), D6O and NP30, against major bacterial pathogens of fish. In vivo tests on rainbow trout were preceded by tests of in vitro minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC). NP30 exhibited higher efficacy, but both iBCA-NPs demonstrated dose-dependent and species-specific in vitro antibacterial properties against the bacterial isolates. Generally, Gram-negative bacteria were more resistant to the iBCA-NPs. Streptococcus iniae, Tenacibaculum maritimum, and Photobacterium damselae were particularly sensitive to both iBCA-NPs. Orally administered to rainbow trout, the iBCA-NPs produced relative gain rate and survival rates comparable to the control (P > 0.05). Condition factor, hepatosomatic and viscerosomatic indices of fish were indifferentiable (P > 0.05) between the iBCA-NP groups and the control. The iBCA-NPs caused no alteration in stress, oxidative stress (superoxide dismutase, SOD), plasma complement titre, and lysozyme activity. The results of this study suggest that D60 and NP30 may contribute to reducing the amount of antibiotics and chemotherapeutic agents being used in aquaculture.

Fifteen new diterpenoids, namely xishaklyanes A-O (1-15), along with three known related ones (16-18), were isolated from the soft coral Klyxum molle collected from Xisha Islands, South China Sea. The stereochemistry of the new compounds were elucidated by a combination of detailed spectroscopic analyses, chemical syntheses, quantum chemical calculations and comparison with the reported data. The absolute configuration of compound 18 was established by the modified Mosher's method for the first time. In bioassay, some of these compounds exhibited considerable antibacterial activities on fish pathogenic bacteria, and compound 4 showed the most effective activity with MIC of 0.225 g/mL against Lactococcus garvieae.

Rapid developing antimicrobial resistance due to broad antibiotic utilisation in healthcare and food industries and the non-availability of novel antibiotics represents one of the most critical public health issues worldwide. The current advances in nanotechnology allow new materials to address drug-resistant bacterial infections in specific, focused and biologically safe ways. The unique physicochemical properties, biocompatibility, and wide range of adaptability of nanomaterials that exhibit photothermal capability can be employed to develop the next generation of photothermally induced controllable hyperthermia as antibacterial nanoplatforms. Here, we review the current state-of-the-art in different functional classes of photothermal antibacterial nanomaterials and the strategies to optimise antimicrobial efficiency. The recent achievements and trends in developing photothermally active nanostructures, including plasmonic metals, semiconductor, carbon-based, and organic photothermal polymers, and antibacterial mechanisms of action, including anti-multidrug resistant bacteria and biofilms removal, will be discussed. Insights into mechanisms of the photothermal effect and various factors influencing photothermal antimicrobial performance, emphasising the structure–performance relationship, are discussed. We will examine the photothermal agents’ functionalisation for specific bacteria, effects of near-infrared light irradiation spectrum, or active photothermal materials for multimodal synergistic-based therapies to minimise side effects and maintain low cost. Most relevant applications are presented, such as anti-biofilm formation, biofilm penetration or ablation, and nanomaterial-based infected wound therapy. Practical antibacterial applications employing the photothermal antimicrobial agents, alone or in synergistic combination with other nanomaterials, are considered. Existing challenges and limitations in photothermal antimicrobial therapy and future perspectives are presented from the structure, function, safety, and clinical potential points of view.

Antibiotics have become a widely used drug classes worldwide. Its indiscriminate use in the clini-cal-hospital environment ended up causing antibiotic-resistance genes. Pharmaceutical technology is an essential ally for new formulation development in the antibacterial field. Cyclodextrins (CDs) are ap-proaches that can potentially improve the effectiveness of antibacterial drugs. Thus, this study aimed to review experimental models using CDs as inclusion complexes to improve antibacterial drugs’ physi-cochemical characteristics and biological activities. The review was carried out using the three online journals database PubMed, Scopus, and Embase, limited to Medical Subjects Headings Index. The search protocol was registered in the Open Science Framework database. The following terms and their com-binations were used: cyclodextrins and antibacterial agents in title or abstract, and a total of 1580 studies were identified in a period up to October 2022. Finally, 27 articles were selected for discussion in this review. The biological results reveal that the antibacterial effect of the compounds, complexed with CDs, was extensively improved when compared to the free drugs. CDs can improve the therapeutic effects of antibiotics, already existing on the market, natural products, and synthetic molecules. Therefore, these inclusion complexes using CDs increase the new pharmaceutical products development for clinical ap-plication.

Hydrogels can provide instant relief to pain and facilitate the fast recovery of wounds. Currently the incorporation of medicinal herbs/plants in polymer matrix is being investigated due to their anti-bacterial and wound healing properties. Herein, we investigated the novel combination of chitosan (CS), chondroitin sulfate (CHI) and garlic (Gar) to synthesize hydrogels through freeze gelation process for faster wound healing and resistance to microbial growth at the wound surface. The synthesized hydrogels were characterized via Fourier transform infrared spectroscopy (FTIR), which confirmed the presence of relevant functional groups. The scanning electron microscopy (SEM) images exhibited the porous structure of the hydrogels, which is useful for the sustained release of Gar from the hydrogels. The synthesized hydrogels showed significant inhibition zones against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). Furthermore, cell culture studies confirmed the cyto-compatibility of the synthesized hydrogels. Thus, the novel hydrogels presented in this study can offer antibacterial effect during wound healing and promote tissue regeneration.

The Kalanchoe genus is composed of more than 100 species that usually thrive in tropical environments, which have been used in folkloric medicine to treat various illnesses, including dermatological conditions. With this, the present study assesses the pharmacognostical and pharmacological properties of different species of the Kalanchoe genus as elements for a potential treatment for dermatological-related conditions, from findings of existing literature and studies. It was analyzed that the Kalanchoe pinnata plant, or one of the most common species of Kalanchoe, have been observed to have distinct morphological and microscopic characteristics. Further, it was discovered that different species of Kalanchoe have anti-inflammatory, antioxidant, antibacterial, and wound healing properties, which enable the plant to be used for dermatological products that are available to the market. With this, it is recommended that further studies be conducted in other understudied species of Kalanchoe regarding their pharmacological properties, as well as the use of other structures of the Kalanchoe plant for treatment of various dermatological conditions.

Organically-coated nanomaterials are intensively studied and find numerous applications in a wide range of areas ranging from optics to biomedicine. One of the recent trends in material science is the application of bio-mimetic polydopamine coatings that can be produced on a variety of substrates in a cost-efficient way under mild conditions. Such coatings not only modify the biocompatibility of the material but also add functional amino groups to the surface that can be further modified by classic conjugation techniques. Here we show an alternative strategy of substrates modification using not dopamine but dopamine conjugates. Compared to the classic scheme the proposed strategy allows for separation of the "organic" and "colloidal" stages and simplifies identification and purification steps. Modification with pre-modified dopamine allowed to achieve high active components loading up to 10.5% wt. A series of organo-inorganic hybrids were synthesized and their bioactivity was analyzed.

Peri-implantitis occurs at a significant rate, which is the leading cause of implant failure. The main reason for this unwanted complication is bacterial invasion and biofilm formation. To reduce the incidence of peri-implantitis, we constructed a carboxymethyl dextran (CMD) based nanomicelles antibacterial coating on microarc-oxidized titanium (MAO-Ti) surface. After cross-linking, the drug-loaded nanomicelles were spherical with a particle size of 130nm and uniformly dispersed. Zeta potential was negative, and the absolute value was greater than 10 mV, effectively avoiding micelles aggregation. It was observed by dynamic light scattering (DLS) that the stability of nanomicelles was significantly improved after cross-linking. The hemolysis rate of micelles was less than 5%, and the overall survival rate of human umbilical vein endothelial cells was more than 90%. After being coated on MAO-Ti surface, the cumulative drug release rate of drug-loaded nanomicelles reached 86.6% after 360 hours. Fluorescence staining of immobilized bacteria showed more dead bacteria on the coating surface, and the number of live bacteria was significantly reduced. It was concluded that dextran-based nanomicelles, which showed long-term drug release properties and excellent biocompatibility, are potential drug carriers for fabricating antibacterial coating on titanium surfaces.

Abstract: Bacterial biofilms are highly resistant to antibiotics and have been implicated in the etiology of 60-80% of chronic microbial infections. We tested a novel combination of low intensity ultrasound and blue light against biofilm and planktonic bacteria. A laboratory prototype was built which produced both energies uniformly and coincidently from a single treatment head, impinging upon a 4.45 cm^2 target. To demonstrate proof of concept, Propionibacterium acnes biofilm was cultured on Millicell hanging inserts in 6-well plates. Hanging inserts with biofilm were treated in a custom exposure chamber designed to minimize unwanted ultrasound reflections. Coincident delivery of both energies demonstrated synergy over either alone, killing both stationary planktonic and biofilm cultures of P. acnes. Biofilm killing was dose dependent on exposure time (i.e. energy delivered). P. acnes biofilms were significantly reduced by the dual energy treatment (p<0.0001), with a >1 log10 reduction after a 5 min (9 J/cm^2) and >3 log10 reduction after a 30 min (54 J/cm^2) treatment (p<0.05). Mammalian cells were found unaffected by the treatment. Both the light and the ultrasound energies are at levels previously cleared by the FDA. Therefore, this combination treatment could be used as a safe, efficacious method to treat biofilm related syndromes.

The present study examined the volatile composition and antimicrobial and gastrointestinal activity of the essential oils of Elettaria cardamomum (L.) Maton harvested in India (EC-I) and Guatemala (EC-G). Monoterpene were present in higher concentration in EC-I (83.24%) than in EC-G (73.03%), whereas sesquiterpenes were present in higher concentration in EC-G (18.35%) than in EC-I (9.27%). Minimum inhibitory concentrations (MICs) of 0.5 and 0.1 mg/mL were demonstrated against Pseudomonas aeruginosa in EC-I and EC-G, respectively, whereas MICs of 0.125 and 1 mg/mL were demonstrated against Escherichia coli in EC-I and EC-G, respectively. The treatment with control had the highest kill-time potential, whereas the treatment with oils had shorter kill-time. EC-I was found to be more potent in the castor oil-induced diarrhoea model than EC-G. At 100 and 200 mg/kg, EC-I exhibited 40% and 80% protection, respectively, and EC-G exhibited 20% and 60% protection, respectively, in mice, whereas loperamide (positive control) exhibited 100% protection. In the in vitro experiments, EC-I inhibited both carbachol (CCh, 1 µM) and high K+ (80 mM)-induced contractions at significantly lower concentrations than EC-G. Thus, EC-I significantly inhibited P. aeruginosa and E. coli and exhibited more potent antidiarrheal and antispasmodic effects than EC-G.

In this study, silver-strontium doped hydroxyapatite (AgSr-HA)/chitosan composite coatings were deposited on stainless steel (SS) substrate via electrophoretic deposition (EPD) technique. The EPD parameters such as the concentration of Ag Sr-HA particles in the suspension, applied voltage and deposition time were optimized on by the Taguchi Design of Experiment (DoE) approach. DOE approach elucidated that the “best” coating was obtained at; the deposition voltage of 20V, deposition time of 7 minutes, and at 5 g/L of Ag Sr-HA particles in the suspension. The optimum coatings were characterized by using scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) spectroscopy. SEM images confirmed the deposition of chitosan/Ag Sr-HA on the SS substrate. The wettability studies indicated the hydrophilic nature of the chitosan/Ag Sr-HA coatings, which confirmed the suitability of the developed coatings for orthopedic applications. The average surface roughness of the chitosan/Ag Sr-HA coatings was in a suitable range for the attachment of bone marrow stromal cells. Chitosan/Ag Sr-HA coatings showed a potent antibacterial effect against the Gram-Positive and Gram-negative bacteria.

This work emphasizes to use silver decorative method to enhance the antibacterial activity of TiO₂ and ZnO nanoparticles. These silver decorated nanoparticles (hybrid nanoparticles) were synthesized by using sodium borohydride as a reducing agent, with the weight ratio of Ag precursors: oxide nanoparticles = 1: 30. The morphology and optical property of these hybrid nanoparticles were investigated using transmission electron microscopy (TEM) and UV–vis spectroscopy. The agar-well diffusion method was used to evaluate their antibacterial activity against both Staphylococcus aureus and Escherichia coli bacteria, with or without light irradiation. The TEM images indicated clearly that silver nanoparticles (AgNPs, 5-10 nm) were well deposited on the surface of nano-TiO₂ particles (30-60 nm). Besides, smaller AgNPs (< 2 nm) were dispersed on the surface of nano-ZnO particles (20-50 nm). UV-vis spectra confirmed that the hybridization of Ag and oxide nanoparticles led to shift the absorption edge of oxide nanoparticles to the lower energy region (visible region). The antibacterial tests indicated that both oxide pure nanoparticles did not exhibit inhibitory against bacteria, with or without light irradiation. However, the presence of AgNPs in their hybrids, even at low content (< 40 mg/mL) leads to a good antibacterial activity and the higher inhibition zones under light irradiation as compared to that in dark was observed.

An efficient procedure for the synthesis of polyhydroxyl aromatic compounds (phloroglucide analogs) is described. In this procedure a reaction was done between different 4-substituted phenols and 2,6-bis(hydroxymethy) phenols. The reactions proceed in the presence of catalytic amount of silica gel supported boric tri-sulfuric anhydride (SiO2-BTSA) in excellent yields. 16 compounds were synthesized (I1-I16). Chemical structures of all compounds were confirmed by spectroscopic methods. We optimized the chemical reactions in the presence of different acidic catalysts, different solvents and also different temperatures. Catalytic amounts of SiO2-BTSA in dichloroethane (DCE) was the best conditions. Some of the synthesized compounds were screened for their antimicrobial activities. Antifungal and antibacterial activities of the synthesized compounds were evaluated by broth micro dilution method as recommended by CLSI. Some of the tested compounds show good in vitro biological properties.

New approaches to deal with drug-resistant pathogenic bacteria are urgent. We studied the antibacterial effect of chitosans against an E. coli quorum sensing biosensor reporter strain, and selected a non-toxic chitosan to evaluate its QS inhibition activity and its effect on bacterial aggregation. To this end, chitosans of varying DA (12 to 69%) and M_w (29 to 288 KDa) were studied. Only chitosans of low DA (~12%) inhibited the bacterial growth, regardless of the M_w. Chitosan MDP DA30 (DA 42% and M_w 115 kDa) was selected for further QS inhibition and SEM imaging studies. MDP DA30 chitosan exhibited QS inhibition activity in an inverse dose-dependent manner (≤12.5 µg/mL). SEM images revealed that this chitosan, when added at low concentration (≤30.6 µg/mL), induced substantial bacterial aggregation, whereas at high concentration (234.3 µg/mL), it did not. Aggregation explains the QS inhibition activity as the consequence of retardation of the diffusion of AHL.

Silver nanoparticles (AgNPs) have been demonstrated to restrain bacterial growth while maintaining the minimal risk in development of bacterial resistance and human cell toxicity that conventional silver compounds exhibit. Several physical and chemical methods have been reported to synthesize AgNPs. However, these methods are expensive and involve heavy chemical reduction agents. An alternative approach to produce AgNPs in a cost-effective and environmentally friendly way employs a biological pathway using various plant extracts to reduce metal ions. The size control issue and the stability of nanoparticles remain some of the latest challenges in such methods. In this study, we used two different concentrations of fresh leaf extract of the plant Arbutus Unedo (LEA) as a reducing and stabilizing agent to produce two size variations of AgNPs. UV-Vis spectroscopy, Dynamic Light Scattering, Transmission Electron Microscopy and zeta potential were applied for the characterization of AgNPs. Both AgNP variations were evaluated for their antibacterial efficacy against the gram-negative species Escherichia coli and Pseudomonas aeruginosa, as well as the gram-positive species Bacillus subtilis and Staphylococcus epidermidis. Although significant differences have been achieved in the nanoparticles’ size by varying the plant extract concentration during synthesis, the antibacterial effect was almost similar.

Ti and its alloys are the most commonly used materials for biomedical applications. However, bacterial infection after implant placement is still one of the significant rising complications. Therefore, the application of the antimicrobial agents into implant surfaces to prevent implant-associated infection has attracted lots of attention. Scientific papers have shown that inorganic antibacterial metal element (e.g. Ag, Cu, Zn) can be introduced to implant surfaces with the addition of metal nanoparticles or metallic compounds into electrolyte via micro-arc oxidation (MAO) technology. In this review, the effects of the composition and concentration of electrolyte and process parameters (e.g. voltage, current density, oxidation time) on morphological characteristics (e.g. surface morphology, bonding strength), antibacterial ability and biocompatibility of MAO antimicrobial coating were discussed in detail. Anti-infection and osseo-integration can be simultaneously accomplished with the selection of the proper antibacterial elements and operating parameters. Besides, MAO assisted by magnetron sputtering (MS) to endow Ti-based implant materials with superior antibacterial ability and biocompatibility was also discussed. Finally, the development trend of MAO technology in the future was forecasted.

Propionibacterium acnes and Staphylococcus epidermidis are the major skin bacteria that cause the formation of acne. The present study was conducted to investigate antibacterial activity of ethanolic extract of cinnamon bark, honey and their combination against acne bacteria. The antibacterial activity of extract of cinnamon bark and honey were investigated against P. acnes and S. epidermidis using disc diffusion method. Minimum Inhibitory Concentration (MIC) and minimal bactericidal concentration (MBC) were performed using Clinical and Laboratory Standard Institute (CLSI) methods. The interaction combination between extract of cinnamon bark and honey was determined by using a checkerboards method. The results showed that he MIC of extract of cinnamon bark and honey against P. acne were 256 µg/mL and 50% v/v, respectively, while against S. epidermidis were 1024 µg/mL and 50% v/v, respectively. The MBC of extract of cinnamon against P. acnes and S. epidermidis were more than 2048 µg/mL, whereas the MBC for honey against P. acnes and S. epidermidis were 100%. The combination of cinnamon bark extract and honey against against P. acnes and S. epidermidis, showed additive activity with the FICI value 0.625. Therefore, the combination of extract of cinnamon bark and honey has potential activity against acne causing bacteria.

Semen is a complex fluid that contains spermatozoa and also functions as a dynamic bacterial microecosystem, comprising probiotics, pathogenic bacteria, and natural antimicrobial substances. Probiotic bacteria, such as Lactobacillus and Bifidobacterium, along with pathogenic bacteria like Pseudomonas aeruginosa and Escherichia coli, play significant roles in semen preservation and reproductive health. Studies have explored the impact of pathogenic bacteria on sperm quality, providing insights into the bacterial populations in mammalian semen and their influence on sperm function. These reviews highlight the delicate balance between beneficial and harmful bacteria, alongside the role of natural antimicrobial substances that help maintain this equilibrium. Moreover, we discus the presence and roles of antimicrobial substances in semen, such as lysozyme, secretory leukocyte peptidase inhibitors, lactoferrin, and antimicrobial peptides, as well as emerging antibacterial substances like amyloid proteins. Understanding the interactions among probiotics, pathogens, and antimicrobial agents is crucial for elucidating semen preservation and fertility mechanisms. Additionally, the potential for adding probiotic bacteria with recombinant antibacterial properties presents a promising avenue for the development of new semen extenders. This review offers updated insights to understand the equilibrium of bacterial microecosystem in semen and points toward innovative approaches for improving semen preservation.

A comprehensive review of advances in the synthesis and biological applications of enoxacin (ENX) based compounds is presented. ENX, a second-generation fluoroquinolone (FQ) is a prominent 1,8-naphthyridine containing compounds studied in medicinal chemistry. Quinolones, a class of synthetic antibiotics, are crucial building blocks for designing multi-biological libraries due to their inhibitory properties against DNA replication. Chemical modifications at positions 3 and 7 of the quinolone structure can transform antibacterial FQs into anticancer analogs. ENX and its derivatives have been examined for various therapeutic applications, including anticancer, antiviral, and potential treatment against COVID-19. Several synthetic methodologies have been devised for the efficient and versatile synthesis of ENX and its derivatives. This review emphasizes all-inclusive developments in the synthesis of ENX derivatives, focusing on modifications at the C3 (carboxylic acid, Part A), C7 (piperazinyl, Part B), and other positions (Part C). The reactions considered were chosen based on their reproducibility, ease of execution, accessibility, and availability of the methodology reported in the literature. The review provides valuable insights into the medicinal properties of these compounds, highlighting their potential as therapeutic agents in various fields.

Croton grewioides Baill., a species native to the Caatinga, popularly known as canela de cunhã, is used in traditional medicine to treat gastrointestinal diseases such as diarrhea, gastritis and stomach ulcers. This study aimed to identify the chemical composition of the essential oil of C. grewioides (OECG) and evaluate its antibacterial and antibiotic-modulating activities against both standard and multidrug-resistant bacteria. To analyze the compounds, present in the oil, gas chromatography coupled with mass spectrometry (GC/MS) and gas chromatography with flame ionization detector (GC/FID) techniques were used. In the bacteriological tests, the Minimum Inhibitory Concentration (MIC) was obtained using the broth microdilution technique. The modulating effect of the essential oil was determined by calculating the subinhibitory concentration followed by serial microdilution of the antibiotics. The MIC reduction factor (FRC) was calculated and its data expressed as a percentage. Analysis of the chemical composition identified the presence of the major compound estragole with a relative abundance of 50.34%. The MIC values obtained demonstrated efficacy in K. pneumoniae isolated from urine with MIC values of 512 µg/mL. OECG potentiated the effects of all antibiotics tested on S. aureus ATCC 29213, K. pneumoniae Carbapnemase, E. coli ATCC 25922 and S. aureus ATCC 29213 strains with their FRC of 97.65 %, 99.80 %, 99.85 % and 99.88 %, respectively. Thus, the essential oil of C. growioides presents synergistic effects when combined with the tested antibiotics, in addition to acting in the fight against bacterial resistance to antibiotics.

Elemental sulfur, commonly known for its wide range of biological activity, has a long history of being used to protect all garden and vegetable crops from a range of pests and diseases, including powdery mildew, ascochyta blight, clubroot, plant mites, oidium, anthracnose, and scab. In the present study, a quick and environmentally friendly approach has been developed for the synthesis of sulfur nanoparticles with antibacterial activity. Sulfur nanoparticles (SNPs) were prepared by modifying the surface of elemental sulfur using various polyelectrolyte-surfactant mixtures (PSM) including NaCMC-SDBS and PHMG-CTAB. The SNPs were characterized by UV–visible spectrophotometry, X-ray diffraction (XRD), and thermogravimetric analysis (TG/DSC), scanning electron microscopy (SEM), with the SNPs showing an almost spherical shape with an average size in the range of 150-200 nm. The antibacterial activity of the sulfur nanoparticles was tested using against gram-positive S. aureus and E. faecium and gram-negative E. coli and P. aeruginosa bacteria. From this, it could be seen that SNPs exhibited significant antimicrobial activity against gram-positive bacteria, i.e., S. aureus and E. faecium. The in vitro cytotoxicity of the SNPs-1 and SNPs-2 studied to normal (MeT-5A) and tumorous (MCF-7) human cell lines was assessed in the concentration range from 500 μg/ml to 0.12 mg/ml, from which it was determined as being non-cytotoxic. The received products can be considered for potential application in agriculture and medicine.

Pseudomonas aeruginosa is an opportunistic pathogen, especially dominant in people with cystic fibrosis; the drug resistance expressed by this pathogen and its capacity for adaptation generate a great challenge for its treatment and control, increasing morbidity and mortality rates globally. In this sense, the search for new treatment alternatives is imminent today, with products of plant origin being an excellent alternative to be used. The objective of this research was to evaluate the antibacterial and antibiofilm potential and to explore the possible effect of ethanolic extracts of wood and bark of Duguetia vallicola on the cell membrane. Microdilution assays showed inhibition of bacterial growth by more than 50%, with the lowest concentration evaluated (62.5μg/mL) of both extracts. Furthermore, we report the ability of both extracts to inhibit mature biofilms, with inhibition percentages between 48.4% and 93.7%. Intracellular material leakage experiments (260/280 nm), extracellular pH measurement, and fluorescence microscopy with acridine orange (AO) and ethidium bromide (EB) showed cell membrane damage. This indicates that the anti-bacterial action of ethanolic extracts of D. vallicola is associated with damage to the integrity of the cell membrane and consequent death of these pathogens. These results serve as a reference for future studies in establishing the mechanisms of action of these extracts.

Ozonated oil has several benefits for humans, as it contributes to numerous interventions, maintaining the quality of life and the well-being of individuals. Being a natural product, it has few or almost no side effects. Thus, the study aimed to verify the sensitivity and/or resistance of fixed o “Ozonated” and “Non-Ozonated” oils from Mauritia flexuosa (Buriti), Carapa guaianensis (Andiroba) and essential “Ozonated” oils from Menta piperita (Mint), Eugenia caryophyllus (Clove) in different concentrations, against internationally known bacteria from the American Type Culture Collection – ATCC, comparing with the “Non-Ozonated” versions of the respective oils, using the Agar diffusion technique. Thus, it is evident that the ozonation of the fixed oils of Buriti and Andiroba, as well as the essential oils of Mint and Clove, provided significant results, although they were statistically different. The Buriti and Andiroba oil were ineffective in inhibiting microorganisms. On the other hand, the essential oil of Mint and Clove obtained similar activity of inhibition of microorganisms. With regard to Ozonation, the Essential Oil of “Ozonated” Clove provided greater activity than the “Non-Ozonated” one, which inhibited only one tested microorganism, in addition to producing changes in its chemical composition, requiring individualized studies for the ozonation of each essential oil.

Ocular pathologies present significant challenges in achieving effective therapeutic re-sults due to various anatomical and physiological barriers. Natural products, such as flavonoids, alone or in association with allopathic drugs, present many therapeutical actions, including anti-cancer, anti-inflammatory, and antibacterial action. However, their clinical employment is chal-lenging for scientists due to their low water solubility. In this study, we designed a liquid formu-lation based on rutin/sulfobutylether-β-cyclodextrin (RTN/SBE-β-CD) inclusion complex for treating ocular infections. The correct stoichiometry and the accurate binding constant were de-termined by employing the SupraFit software on the Uv-vis titration experiment. A deep physical-chemical characterization of the RTN/SBE-β-CD inclusion complex was also performed; it con-firmed the predominant formation of a stable complex (Kc, 9660 M−1) in a 1:1 molar ratio, with high water solubility of 20 times (2.5 mg/mL) higher than the free molecule (0.125 mg/mL), per-mitting the dissolution of the solid complex within 30 min. NMR studies revealed the involve-ment of the bicyclic flavonoid moiety in the complexation, which was also confirmed by molecu-lar modeling studies. In vitro, the antibacterial and antibiofilm activity of the formulation was assayed against Staphylococcus aureus and Pseudomonas aeruginosa strains demonstrating a sig-nificant activity of the formulation to the free components.

This study explores the development of an oil-in-water (O/W) emulsion with a high concentration of ostrich oil, rich in omega-3, -6, and -9 fatty acids, for potential skincare applications. Utilizing Span and Tween emulsifiers, an optimized O/W emulsion containing 20% w/w ostrich oil and 15% w/w mixed emulsifiers was formulated through homogenization, demonstrating the smallest droplet size (5.01 ± 0.43 μm) and appropriate zeta potential (-32.22 mV). The emulsion exhibited antioxidant and antibacterial properties against Staphylococcus aureus, suggesting its suitability for skincare. Stability tests over 6 months at varying temperatures (4 °C, 25 °C, 45 °C) confirmed the emulsion's physical and microbial stability, emphasizing its potential for topical applications. Despite slight changes in acid values (AV) and peroxide values (PV), results remained within acceptable limits. Cytotoxicity assessments on human dermal fibroblasts indicated the emulsion's safety, supporting its suitability for skin application. The emulsion demonstrated antibacterial efficacy against S. aureus and enhanced antioxidant activity compared to ostrich oil alone. The study underscores the importance of emulsification in optimizing the efficacy and stability of ostrich oil in skincare formulations, offering valuable insights for practical applications where stability is critical.

Honey has been employed for the treatment of wounds and diseases for ancient time, thanks to its antimicrobial and curative properties. This study aims to present the biochemical characteristics, including the amount of sugar, total phenols, phenolic chemicals, antioxidant properties, and antibacterial activities of a specific type of French honey (Sologne summer forest) in comparison with a manuka honey. According to our findings, the Manuka honey tested has 23% fewer polyphenols total than Sologne summer forest honey. The results showed that the Sologne summer honey had a different polyphenols profile than Manuka honey with specific polyphenol like p- Hydroxybenzoic acid. Additionally, the antioxidant activity of the two honeys is comparable (9 μmole Trolox.g-1 honey). Furthermore, the antibacterial activity of the two honeys is comparable against Pseudomonas aeruginosa and Staphylococcus aureus. Our research indicates for the first time that there are significant nutritional and biological potentials for a French honey from the Sologne summer forest.

Nanofibers are one of the most attractive materials that can modify functionalities for developing new kinds of specific applications, mainly used as a biomedical material. Herein, we designed and prepared the antibacterial nonwoven fiber mats of PLA and PLA composited with Ag nanoparticles by electrospinning. The effects of varying filler contents on their chemical, surface morphology, thermal, water absorbency, and antibacterial properties were investigated using FTIR, SEM/EDS, DSC, swelling ratio, and qualitative and quantitative antibacterial tests. FTIR and EDS spectra indicated that Ag nanoparticles were incorporated in the PLA without chemical bonding. SEM revealed that the average diameter of the PLA nanofibers containing the Ag nanoparticles was more significant than those without those particles. Besides, fiber diameters are proportionally the amount of Ag nanoparticle contents. DSC indicated that the Ag nanoparticles can be incorporated within the PLA-matrix without strongly affecting their thermal properties. Moreover, the crystallinity of the composite nonwoven fiber mats was higher than those of fiber mats in the neat PLA. Accordingly, the antibacterial activities revealed that all the composite nanofiber mats exhibited excellent against S. aureus and E. coli bacterial strains. In addition, in the cell toxicity study, all produced hybrids nonwoven fiber mats induced a reduction in cell viability for the L929 fibroblast cells. Our results suggest that the designed and prepared nonwoven fiber mats may have good potential for use in the biomedical field, particularly in wound dressing applications

Background: We investigated the effect of bioactive glass and zinc oxide nanoparticles on enamel remineralization, as well as their antibacterial effect on cariogenic bacteria. Methods: Fluoride gel (F), bioactive glass microparticles (µB), bioactive glass nanoparticles (nB), zinc oxide nanoparticles (Z), and a mixed suspension of nB and Z (nBZ) were prepared and subjected to the following tests: morphological evaluation by scanning and transmission electron microscopy, measurement of specific surface area, zeta potential measurement, crystal structure analysis by X-ray diffraction, and acid buffering capacity test. Further, we performed a remineralization cycle test of 28 days and a nanoindentation testing was carried out during the immersion period and then the enamel surfaces were examined using scanning electron microscopy. Additionally, the antibacterial effects of the sample suspensions were evaluated by measuring their minimum bactericidal concentrations against various cariogenic bacteria. Results: Our results revealed that nB had a near-circular shape with an amorphous structure, a considerably large specific surface area due to nanoparticulation. Additionally, nB possessed a rapid acid buffering capacity, which was comparable to that of μB. In the remineralization test, faster recovery of mechanical properties was observed on the enamel surface immersed in samples containing bioactive glass nanoparticles (nB and nBZ). After remineralization, demineralized enamel immersed in any of the samples showed a rough and porous surface structure covered with mineralized structures. Furthermore, nBZ exhibited a broad antibacterial spectrum. Conclusions: These results demonstrated that bioactive glass and zinc oxide nanoparticles have superior demineralization-suppressing and remineralization-promoting effects.

Various 4-aminotetrahydropyridinylidene salts were treated with aldehydes in alkaline medium. Their conversion to 5-substituted -hydroxyketones in a one-step reaction succeeded only with an aliphatic aldehyde. Instead, aromatic aldehydes gave 5-substituted -aminoketones or a single -diketone. The new compounds were characterized by spectroscopic methods and a single crystal structure analysis. Some of them showed anticancer and antibacterial properties.

Potentially, such an approach would significantly increase the effectiveness of therapy for a number of infectious and other diseases, reduce the dosage of antibiotics, shorten the duration of treatment, and reduce the risk of developing resistance. Moreover, the use of a polymer carrier with covalently bound organic molecules of different structures avoids problems with different (suboptimal) solubility and bio-distribution, which would be almost inevitable when using the same compounds separately. It would be very difficult to find antibiotic/adjuvant pairs that simultaneously achieve optimal concentrations in the same target cells. In our case, terpenoids and alkylbenzenes used as adjuvants are practically insoluble as individual compounds and their unacceptable pharmacological properties would not allow them to be used as efflux pump inhibitors.

Present study reports the green synthesis of pectin fabricated silver-based nanocomposite (Pectin-AgNPs) with Carpesiumnepalense leaves extract and evaluated their bactericidal kinetics, in-vivo hepatoprotective and cytotoxic potentials with their possible mechanisms. GC/MS and LC/MS analysis indicated the presence of different new phytochemicals constituents in the plant extract. The physicochemical characterization of Pectin-AgNPs by UV/Vis, SEM, DLS, FTIR and EDX techniques showed the spherical and uniform size range synthesis of nanocomposite i.e. 50-110 nm. The highly significant (P<0.005) antibacterial activity was found against all tested four bacterial strains with the ZIs of 24.8 to 27.2 mm. Significant damage in bacterial cell membrane was also observed in AFM study after treated with Pectin-AgNPs. At the doses of 0.05 mg/kg, nanocomposite showed highly significant (P<0.005)hepatoprotective activity in biochemical and histopathology analysis as compared to CCL4 administered control group. The ameliorative effects of Pectin-AgNPs were observed in PCR analysis on both GAPDH and PPARs genes expression and its potential to restore gene alterations caused by CCl4 intoxication.Pectin-AgNPs produced cytotoxic activity against HeLa cell lines at higher doses with the LC50 of 223.7 µg/mL. The current findings demonstrate positive attributes of pectin fabricated AgNPs as a promising antibacterial, hepatoprotective and cytotoxic agent.

Nowadays, there is evidence that bacteria can contribute to cancer formation and interfere with therapy by mediating its carcinogenesis and related infection. Moreover, it is acknowledged that microbial infections and antibiotic resistance represent severe economic and health risks to society. These facts have led to the developing of several new techniques for impeding crucial biological processes in microbial cells. One of these techniques centers on using metal-chelating agents, which can disrupt the microorganism's vital metal metabolism by obstructing metal uptake and bioavailability for critical reactions. Additionally, nanotechnology has made a wide range of nanomaterials available for possible uses in the antibacterial industry. This complex field is shaped by antimicrobial nanoparticles, also investigated as therapeutic and drug-delivery tools. Halloysite nanotubes (HNTs) are naturally occurring tubular clay nanomaterials consisting of aluminosilicate kaolin sheets rolled up several times. The aluminon and siloxane groups on the surface of HNTs facilitate the formation of hydrogen bonds with biomaterials on their surface. These properties make HNTs crucial in a wide range of applications, such as in environmental sciences, wastewater treatment, dye removal, nanoelectronics and nanocomposite fabrication, catalytic studies, coatings for glass or anti-corrosive coatings, cosmetics, flame retardants, stimulus-response, and in forensic sciences. This work aimed to produce an antibacterial material by combining the properties of halloysite nanotubes with the ability of kojic acid to chelate iron. Starting from kojic acid, a simple nucleophilic substitution involving the hydroxyl groups on the surface of the nanotubes was performed. The obtained material was characterized by IR and SEM, and its ability to chelate iron was evaluated. Finally, the capacity to load drugs such as resveratrol and curcumin was also evaluated by UV analysis. In this way, a new bio-based material that can be used as a drug carrier and antimicrobial was produced.

The development of magnesium calcium phosphate bone cements (MCPCs) have garnered big attention. MCPCs are bioactive and biodegradable and have appropriate mechanical and antimicrobial properties for use in reconstructive surgery. In this study, the cement powders based on a (Ca + Mg)/P = 2 system doped with Zn2+ at 0.5 and 1.0 wt.% were obtained and investigated. After the mixing with a cement liquid, structural and phase composition, morphology, chemical structure, setting time, compressive strength, degradation behavior, solubility, antibacterial activities, and in vitro behaviour of the cement materials were examined. A high compressive strength of 48 ± 5 MPa (mean ± SD) was achieved for the cement made from Zn2+ 1.0-wt.%-substituted powders. The Zn2+ introduction led to antibacterial activity against Staphylococcus aureus and Escherichia coli strains, with an inhibition zone diameter up to 8 mm. Biological assays confirmed that the developed cements are cytocompatible and promising as a potential bone substitute in reconstructive surgery.

Graphene-based nanomaterials have emerged as promising materials for a wide range of applications.. Therefore, in the last years carbon nanoparticles have attracted great attention due to their low toxicity, high biocompatibility and easy preparation. Recently, N-doped carbon nanoparticles have been shown to have improved antibacterial activity over the undoped nanomaterial, but it is difficult to find correlations between the structure of the nanoparticle and its antibacterial activity. With this purpose, here, we analyze the effect of both, the nanoparticle size and the surface chemical composition of four N-doped carbon nanoparticles on the growth of Escherichia coli bacteria. Our results were analyzed using a Ligand-Substrate model based on the Monod´s equation, which allows us to interpret the dependence of the nanoparticle-bacteria affinity with the nanomaterial structure.

Guava (Psidium guajava L.) is a common fruit tree that grows in several tropical and subtropical parts of the world. The aim of this study was to employ the use of liquid-liquid fractionation to investigative the comparative antibacterial potential of crude extracts of Guava leaves and bark against selected food isolates; Escherichia coli, Pseudomonas aeruginosa, Streptococcus pneumonia, Bacillus cereus and Staphylococcus aureus. The phytochemical analysis of the extract showed presence of tannin, phenol, flavonoid and terpenoid in all extract, while steroid and saponin were absent in some. The agar diffusion method was employed for the assessment of the sensitivity of the extracts. The ethyl acetate and aqueous fractions from the stem bark acetone extract generally showed better antimicrobial activity compared with other extracts from leaves. The extract was active both against gram positive bacteria (Bacillus cereus and Streptococcus pneumonia) and gram negative bacteria (Escherichia coli, Pseudomonas aeruginosa, , Bacillus cereus and Staphylococcus aureus) at varying zone of inhibition. The results of the study showed the potential of identifying novel antibacterial agent from P. guajava bark and leaves while optimising the potential application for treatment in traditional medicine.

New generation antibiotics are needed to combat the development of resistance to antimicrobials. One of the most promising new classes of antibiotics is cannabidiol (CBD). It is a non-toxic and low-resistance chemical that can be used to treat bacterial infections. The antibacterial activity of Cannabis sativa L. byproducts, specifically CBD, has been of growing interest in the field of novel therapeutics. As research continues to define and characterize the antibacterial activity that CBD possesses against a wide variety of bacterial species it is important to examine potential interaction between CBD and common therapeutics such as broad-spectrum antibiotics. Here, we show that CBD-antibiotic co-therapy can effectively fight S. typhimurium via membrane integrity disruption. This research serves to examine the potential synergy between CBD and three broad-spectrum antibiotics for potential antibiotic-CBD co-therapy. In this study, we reveal that Salmonella typhimurium (S. typhimurium) growth is inhibited at very low dosages of CBD-antibiotic. This interesting finding demonstrates that CBD and CBD-antibiotic co-therapies are viable novel alternatives to combating Salmonella typhimurium.