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

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.

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.

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.

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.

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.

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.

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.

We report here the synthesis of uniform nanospheres-like silver nanoparticles (AgNPs, 5-10 nm) and the dumbbell-like Fe3O4-Ag hybrid nanoparticles (FeAgNPs, 8-16 nm) by the use of seeding growth method in the presence of oleic acid (OA)/oleylamine (OLA) as surfactants. The antibacterial activity of pure nanoparticles and nanocomposites by monitoring the bacterial lag–log growth has been investigated. The electron transfer from AgNPs to Fe3O4NPs which enhances the biological of silver nanoparticles has been proven by nanoscale Raman spectroscopy. The lamellae structure in the spherulite of FeAgNPs/PE nanocomposites seems play the key role to the antibacterial activity of nanocomposites, which has been proven by nanoscale AFM-IR. An atomic force microscopy coupled with nanoscale infrared microscopy (AFM-IR) is use to highlight the distribution of nanoparticles on the surface of nanocomposite at the nanoscale. The presence of FeAgNPs in PE nanocomposites has a better antibacterial activity than that reinforced by AgNPs due to the faster Ag+ release rate from the Fe3O4-Ag hybrid nanoparticles and the ionization of AgNPs in hybrid nanostructure.

Egg white lysozyme was modified by chemical methods using organic acids. Caffeic acid and p-coumaric acid in organic acids were used as modifiers, and 1-Ethyl-3- (3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxy succinimide were used as dehydration condensation agents during modification. A certain degree of modified lysozyme was obtained through appropriate modification conditions. The antibacterial properties and structure of the obtained two organic acid modified lysozymes were compared with natural enzymes. The results showed that compared with the natural enzyme, the activity of modified lysozyme decreased, but the inhibitory effect on Gram-negative bacteria was enhanced. The minimum inhibitory concentrations of caffeic acid modified enzyme and p-coumaric acid modified enzyme on Escherichia coli and Pseudomonas aeruginosa were 0.5 mg/mL and 0.75 mg/mL, respectively. However, the antibacterial ability of modified lysozyme to Gram-positive bacteria was lower than that of natural enzyme. The minimum inhibitory concentration of caffeic acid modified enzyme and p-coumaric acid modified enzyme to Staphylococcus aureus and Bacillus subtilis was 1.25 mg/mL. The peak fitting results of the amide-I band (1600 cm-1-1700 cm-1) absorption peak in the infrared spectroscopy showed that the content of the secondary structure of the two modified enzymes obtained after modification was different from that of natural enzymes.

Introduction: Bacterial resistance is a worldwide public health problem, requiring new therapeutic options. An alternative approach to this problem is the use of animal toxins, such as phospholipases (PLA₂) isolated from snake venom, which have important biological activities. Bothrops erythromelas is one of the snake species in the Northeast of Brazil that attracts great medical-scientific interest. Here we aimed to purify and characterize a PLA₂ from B. erythromelas, searching for heterologous activities against bacterial biofilm. Methods: Venom extraction and quantification were followed by RP-HPLC in C18 column, MALDI-ToF mass spectrometry and sequencing by Edman degradation. All experiments were monitored by specific activity using 4-nitro-3 (octanoyloxy) benzoic acid (4N₃OBA) substrate. In addition, hemolytic tests and anti-bacterial tests including action against Escherichia coli, Staphylococcus aureus and Acinetobacter baumannii, were carried out. Moreover, tests of antibiofilm action against A. baumannii were also performed. Results: PLA₂, after one purification step, presented 31 N-terminal amino acid residues, and molecular weight of 13656.4 Da with enzymatic activity confirmed in 0.06 µM concentration. Antibacterial activity against S. aureus (IC₅₀ = 30.2 µM) and antibiofilm activity against A. baumannii (IC₅₀ = 1.1 µM) were observed. Conclusions: This is the first time that PLA₂ purified from B. erythromelas venom has appeared as an alternative candidate in studies of new antibacterial medicines.

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.

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.

Different products from a unique Propolis extract, Propolis (bee glue), an of resinous consistency produced by bees, has been used as indigenous medicine for the treatment of several diseases in some contrary. Safety assessment of propoils extracts with respect to antimicrobial activity against three bacterial isolates, Proteus Mirabilis , Klebsiella Pneumonia and Staphylococcus Qureus.The result showed that the main composition of the extract was Anthraquinone, the last one was responsible for the biological activity of the extract. FT-IR, UV results showed more than eight peaks for represent the main fine composition of the extract. The present study also showed that the extract has antibacterial activity against three bacterial isolates

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.

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

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.

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.

Active films based on carboxymethyl chitosan incorporated corn peptide were developed. Physicochemical properties of the films, including thickness, opacity, moisture content, color, mechanical properties, water vapor permeability, and oil resistance, were measured. Biological activities of the films, including the antioxidant and antibacterial activities, were characterized in terms of 2, 2-diphenyl-1-picrylhydrazyl free radical scavenging activity, reducing power, the total antioxidant activity, and the filter disc inhibition zone method. The results indicated that the incorporation of corn peptide caused interactions between carboxymethyl chitosan and corn peptide in Maillard reaction and gave rise to the films light yellow appearance. Compared with the Control, the degree of glycosylation, browning intensity, thickness, opacity, tensile strength, antioxidant activity, and antibacterial activity of films were increased, but the elongation, vapor permeability, and oil resistance of films were decreased. The films based on corn peptide and carboxymethyl chitosan can potentially be applied to food packaging.

Investigation of the methanol extract of the poroid fungus Fuscoporia torulosa resulted in the isolation of a novel triterpene, fuscoporic acid (1) together with inoscavin A and its previously undescribed Z isomer (2 and 3), 3,4-dihydroxy-benzaldehide (4), osmundacetone (5), senexdiolic acid (6), natalic acid (7), and ergosta-7,22-diene-3-one (8). The structures of fungal compounds were determined on the basis of NMR and MS spectroscopic analysis, as well as molecular modelling studies. Compounds 1, 6-8 were examined for their antibacterial properties on resistant clinical isolates, and cytotoxic activity on human colon adenocarcinoma cell lines. Compound 8 was effective against Colo 205 (IC50 11.65±1.67 µM), Colo 320 (IC50 8.43±1.1 µM) and MRC-5 (IC50 7.92±1.42 µM) cell lines. Potentially synergistic relationship was investigated between 8 and doxorubicin, which revealed a synergism between the examined compounds with a combination index (CI) at the 50% growth inhibition dose (ED50) of 0.521±0.15. Several compounds (1, and 6-8) were tested for P‐glycoprotein modulatory effect in Colo 320 resistant cancer cells, but none of the compounds proved to be effective in this assay. Fungal metabolites 2-5 were evaluated for their antioxidant activity using the oxygen radical absorbance capacity (ORAC) and DPPH assays. Compounds 4 and 5 proved to possess considerable antioxidant effect with EC50 0.25±0.01 (DPPH) and 12.20±0.92 mmol TE/g (ORAC). The current article provides valuable information on both chemical and pharmacological profiles of Fuscoporia torulosa, paving the way for future studies with this species.

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.

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.

Postbiotic is a preparation of inanimate microorganisms and/or their components that confers a health benefit on the host. Different bacterial strain and preparation method result in different functions. Herein, a postbiotic preparation named Postbiotic-P by intercepting 1-5 KD of the cell-free supernatants of L. caseiparacasei P6 fermentation broth was prepared, and its multifunctional activities were evaluated. The results showed that Postbiotic-P exerted good antihemolytic (10%-50% Postbiotic-P resulted in 4.9%-48.1% antihemolytic rate), anti-inflammatory (8% to 40% Postbiotic-P is comparable to 259.1-645.4 μg/mL of diclofenac sodium equivalents), antioxidant [reducing power (1.25%-12.5% Postbiotic-P resulted in the increase of OD700 from 0.279-2.322), DPPH free radical scavenging activity (2.5%-50% Postbiotic-P resulted in 38.9%-92.4% free radical scavenging rate), and hydroxyl radical scavenging activity (0.5%-4% Postbiotic-P resulted in 4.66%-10.38% hydroxyl radical scavenging rate)], and antimicrobial activities (against 2 Gram-positive, 8 Gram-negative and 1 fungus). Furthermore, it was proved that Postbiotic-P could significantly inhibit the increase of the peroxide value and the malondialdehyde content in cookies, indicating the application potential of Postbiotic-P in food preservation. Taken together, Postbiotic-P has good application potential for the development of health care products and functional foods. However, further studies are needed to determine their precise mechanism of action, to clarify the active components responsible for the function, and to validate the biological activities in animal models or clinical trials.

The aim of this study was to investigate the physicochemical characterization and biological activities of chitosan (CH) based composite films with the incorporation of chestnut flower essential oil (CFEO). The composite films were prepared by casting method and characterized in terms of structural, morphological and mechanical properties via FT-IR, XRD, UV, SEM and TGA. The results proved the significantly increased water vapor permeability (WVP), heat resistance, antibacterial and antioxidant capabilities of CH-CFEO films. The incorporation of CH and CFEO enhanced the UV blocking, which made the film shield almost all UV light. Films with the tensile strength of 6.37 ± 0.41 MPa and elongation at break of 22.57 ± 0.35% were got with 6 mg mL-1 CFEO. Subsequently, the fruit preservation experiments also confirmed that the composite films could effectively extend the shelf life of bananas through their excellent water vapor and oxygen barrier. These desirable performances enable our newly developed composite films to be a remarkable packaging material to solve the fresh fruit preservation dilemma.

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.

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.

Healthcare-Associated infections (HAIs) affect more than 100 million patients each year worldwide. These infections are mainly caused by multi-resistant bacterial strains (MDR) such as Acinetobacter Baumanii which is responsible of high mortality rate in immunocompromised individuals. However, the treatment is further aggravated by the abuse of antibiotics, the lack of vaccine and the emergence of resistance posing a huge challenge for the discovery of new therapeutic drugs to overcome this nosocomial infection. In this context, antimicrobial peptides with potential antibacterial proprieties could be an alternative. In this research, we describe the synthesis and the bioactivity of dermaseptins and their derivatives against Acitenobacter baumanii. The cytotoxicity of these DS was investigated on the HEp-2 cell line by the MTT cell viability assay. Thereafter, we studied morphological alterations caused by the action of one of the active peptides on the bacterial membrane using Atomic Force Microscopy (AFM). The cytotoxicity of dermaseptins was concentration-dependent at microgram concentrations. It was observed that all tested analogs exhibit antibacterial activity with MICs ranging from 3.125 to 12.5 μg/mL and MBCs ranging from 6.25 to 25 μg/mL. Microscopic images obtained by AFM revealed morphological changes on the surface of treated bacteria caused by K4S4(1-16), as well as significant surface alterations. Overall, these findings demonstrate that DS might constitute new lead structures for the development of potent antibacterial agents against Acinetobacter infections.

To date, various chimeric lysins have been developed as efficacious antibiotics against multidrug-resistant bacteria, but direct comparisons of their antibacterial activities have been difficult due to the preparation of multiple recombinant chimeric lysins. Previously, we reported an E. coli cell-free expression method to screen better chimeric lysins against Staphylococcus aureus, but we still needed to increase the amounts of expressed proteins enough to be able to detect them non-isotopically for quantity comparisons. In this study, we improved the previous cell-free expression system by adding a previously reported artificial T7 terminator and reversing the different nucleotides between the T7 promoter and start codon to those of the T7 phage. The new method increased the expressed amount of chimeric lysins enough for us to detect them using Western blotting. Therefore, the qualitative comparison of activity between different chimeric lysins has become possible via the adjustment of the amount variables between samples without protein purification. We applied it to select more active chimeric lysins derived from our previously reported chimeric lysin (ALS2). Finally, we compared the antibacterial activities of our selected chimeric lysins with reported chimeric lysins (ClyC and ClyO) and lysostaphin, and determined the rank orders of antibacterial activities on different S. aureus strains in our experimental conditions.

In the current study, the physicochemical and microbiological characteristics of this fermented wheat Hamoun were described in detail, as well as the soil properties where this type of wheat was stored. The results showed that the Hamoum had concentrations of the lactic acid of 0.25 g ± 0.03 for the Simeto variety (nine years of storage), as well as 0.13 g ± 0.02 and 0.17 g±0.06 for the Ofanto variety following three and six months, respectively, of storage. The water content varied between 8.3 - 9.7 % for grain and between 10.8- 11.5 % for flour. The ash content of grain and flour of 1.43 ± 0.02 and 1.63 ± 0.26, respectively, was above the normal standards. According to these results, fermented wheat is appropriate for human consumption. The results also showed that the soil where the wheat was stored comprised mainly clay and had an alkaline pH of 8.2. The isolation and identification of fermentable germs showed the presence of lactic acid bacteria belonging to the genera Lactobacillus (59 %), Pediococcus (18 %), Leuconostoc (17 %), and Streptococcus (6 %). The antibacterial activities of isolated acid bacteria against pathogenic germs Escherichia coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 9027), Bacillus cereus (ATCC 14579), and Staphylococcus aureus (ATCC 43300) reflected the presence of strong antibacterial activity, with 62.5 % positive interactions and 100 % pathogenic bacteria inhibited by Lactobacillus.

Essential oils (EOs) have been gaining popularity in the past decades among researchers due to their potential to replace conventional chemicals used in the fight against pests, pathogenic and spoilage microbes and oxidation processes. EOs are complex mixtures with many chemical components the content of which depends on many factors – not just the plant genus, species or subspecies, but also chemotype, locality and climatic conditions, phase of vegetation, method of extraction and others. Due to this fact, there’s still much to study, with antimicrobial effect being one of the key properties of EOs. There are many methods that have been frequently engaged by researchers for in vitro evaluation; however, although the research has been going on for decades, an internationally accepted standard is still missing. Most of methods are based on time-proven standards used for testing of antibiotics. Due to the specific properties of EOs and their components, such as volatility and hydrophobicity, many modifications of these standard procedures have been adopted. The aim of this review is to describe the most common methods and their modifications for testing of antimicrobial properties of EOs and to point out the most controversial variables which can potentially affect results of the assays.

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

Crown of thorns starfish (Acanthaster planci) are coral predators with advantages of having toxicity in their venom and tissue regeneration capabilities. With all these characteristics, only a handful of studies have highlighted the association of microorganisms with this organism. Crown of thorns starfish are common in Fiji and their analyses of microbial diversity for secondary metabolites could be of great interest to the scientific community. This study is an attempt to investigate Fijian-based A. planci for their venom and associated actinomycetes antibacterial activity and further identify the type of enzymes present in the crude venom extract. The CoTS venom extract (0.192 g) harbor enzymes such as gelatinase, caesinase, and amylase. An abundant and potent actinomycete strain, represented as FJA1 showed antibacterial activity against Enterococcus faecium with an inhibition zone of 10 mm. Moreover, all pathogenic test microorganisms were resistant against concentrations of 500 µg and 1 mg of A. planci venom extract.

A series of eight 5-nitrofuran-tagged oxazolyl tetrahydropyrazolopyridines (THPP’s) has been prepared in six stages with excellent regioselectivity. The testing of these compounds against pathogens of ESKAPE panel showed a good activity of lead compound 1-(2-methoxyethyl)-5-(5-nitro-2-furoyl)-3-(1,3-oxazol-5-yl)-4,5,6,7-tetrahydro-1H-pyrazolo[4,3-c] pyridine (13g), which is superior to nitrofurantoin. These results confirmed the benefit of combining a THPP scaffold with a nitrofuran warhead. Certain structure-activity relationships were established in the course of this study which were rationalized by the induced-fit docking experiments in silico.

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.

The collection of forty-nine 8-hydroxyquinoline derivatives, substituted at C5, C6 or C7, was designed and studied by computational methods of modified POM analysis, using SwissADME, Osiris and Molinspiration tool. POM analysis (Petra/Osiris/Molinspiration) and its modified version using SwissADME instead of Petra software are indisputably tools of modern chemoinformatics, often published in the professional literature as well as in the field of research of new antibacterial active compounds, developed to replace existing antibiotics that fail due to increased resistance of bacteria. NitroxolineTM and the group of 8-hydroxyquinoline derivatives with their broad antibacterial effect and the possibility of extensive derivatization of the skeleton, represent a promising direction in the research of new antibacterial active substances. Twenty 8-hydroxyquinoline derivatives were also evaluated on their antibacterial activity against eight selected G+ and G- bacterial strains with a defined resistance mechanism. All structures were in accordance with Lipinski's criteria, twenty-one structures were interesting from the point of view of individual or average value of the bioactivity prediction score and fourteen structures showed one or more mechanisms of toxicity prediction. Furthermore, eleven structures showed a low rate of GI absorption or the inability to cross the BBB barrier, fourteen substances showed a BRENK or PAIN warning, eleven substances are an undesirable substrate of P-glycoprotein and all structures predicted the same level of bioavailability and a relatively low rate of metabolism in the liver. Five structures were selected by the intersection of the POM criteria. The virtual structures 17, 25, 35 and 43 can be favored for the continuity of next study. The resulting scores of bioactivity can indicate the potential of studied structures to be used for the design and development of new active antibacterial agents.

The emergence of multidrug-resistant pathogens such as Listeria monocytogenes and Shiga toxin-producing Escherichia coli (STEC) poses public health challenges, and this has led to a continuous search for effective novel antimicrobial agents. This study aimed to isolate marine actinomycetes from South Africa, evaluate their in vitro antimicrobial activity against Listeria and STEC, and characterize their mechanisms of action. Marine actinoymcetes were isolated and identified by 16S rRNA sequencing. Gas chromatography-mass spectrometry (GC-MS) was used to identify the chemical constituents of bioactive actinomycetes secondary metabolites. Antibacterial activity of the secondary metabolites was assessed by the broth microdilution method and their mode of actions were predicted using computational docking. While five strains showed antibacterial activity during primary screening, only Nocardiopsis dassonvillei strain SOD(B)ST2SA2 exhibited activity during secondary screening for antibacterial activity. GC-MS identified five major bioactive compounds: 1-octadecene, diethyl phthalate, pentadecanoic acid, 6-octadecenoic acid, and tri-fluoroacetoxy hexadecane. SOD(B)ST2SA2`s extract demonstrated the minimum inhibitory con-centration and minimum bactericidal concentration ranging from 0.78–25 mg/ml and 3.13 to > 25 mg/ml, respectively. Diethyl phthalate displayed the lowest bacterial protein binding energies (kcal/mol): −7.2, dihydrofolate reductase; −6.0, DNA gyrase B, and −5.8, D-alanine:D-alanine lig-ase. Thus, marine N. dassonvillei SOD(B)ST2SA2 is a potentially good source of antibacterial compounds that can be used to control STEC and Listeria monocytogenes.

A series of penta-1,4-dien-3-one containing a H-phosphonate scaffold were designed and synthesized. The structures of all title compounds were determined by 1H-NMR, 13C-NMR, 31P-NMR, and HRMS. Bioassay results showed that several of the title compounds exhibited remarkable antibacterial and antiviral activities. Among these, compounds 3c and 3o exhibited substantial antibacterial activities against Xanthomonas oryzae pv. Oryzae (Xoo) and Xanthomonas axonopodis pv. citri (Xac). In addition, compounds 3c, 3f, and 3r showed remarkable curative activities against tobacco mosaic virus (TMV), with 50% effective concentration (EC50) values of 290.0, 234.0, and 373.6 μg/mL, respectively. These were superior to that of ningnanmycin (386.2 μg/mL). Compound 3r exhibited comparative protective activity against TMV, with an EC50 value of 291.1 μg/mL, which was better than that of ningnanmycin (297.1 μg/mL). Notably, the solubility of all title compounds improved relative to the lead compound curcumin. These results suggest that penta-1,4-dien-3-one containing a H-phosphonate scaffold may be considered as an activator for antibacterial and antiviral agents.

Urinary tract infections (UTIs) caused by pathogens, particularly E. coli, have spontaneously become resistant to antimicrobial drugs in recent years. Therefore, regular monitoring and alternative strategies for the antimicrobial agent are crucial for combating antimicrobial resistance and bacterial biofilms. Here, we report a new cobalt iron oxide-conjugated tin oxide nanocomposite that can kill bacteria and treat multidrug-resistant E. coli posing UTIs. Following the isolation and identification of E. coli, we tested 57/134 samples against sixteen commonly used antibiotics phenotypically using the disk diffusion method to determine their sensitivity pattern. Of the 57 E. coli isolates, 66% (38/57) were multidrug-resistant. The E. coli isolates were resistant to cephradine (70.17%), ceftriaxone (59.64%), and azithromycin (59.64%), followed by cefixime (54.38%), cefuroxime sodium (52.63%), and co-trimoxazole (50.87%). X-ray diffraction results showed the crystallite sizes were about 5.68 and 8.84 nm in pure SnO2 nanoparticles and 95% SnO2-5% CoFe2O4 nanocomposite, respectively. Energy-dispersive X-ray spectroscopy and Fourier transform infrared determined the fundamental structure of the nanocomposite, encompassing Co, Fe, Sn, and O. Moreover, FTIR measurements implied that the distinct functional groups in both SnO2 and CoFe2O4 nanoparticles existed in a 95% SnO2-5% CoFe2O4 nanocomposite. Field emission scanning electron microscope analysis uncovered that the SnO2-CoFe2O4 nanocomposite had a size of roughly 24 nm and was spherical. In addition, the biosynthesized SnO2 nanoparticles and SnO2-CoFe2O4 nanocomposite were evaluated for their antibacterial activity. At a minimum 100 µg/mL concentration, SnO2 nanoparticles and SnO2-CoFe2O4 nanocomposite showed high antibacterial activity. The SnO2 nanoparticles and SnO2-CoFe2O4 nanocomposite demonstrated antibacterial activity on multidrug-resistant E. coli at 10 ± 0.7 and 16 ± 0.8 mm zone of inhibition, respectively. In conclusion, the new SnO2-CoFe2O4 nanocomposite might be a potential candidate for treating UTIs caused by drug-resistant E. coli in the foreseeable future.

In this work, a new hybrid compound3,4-diaminopyridinium perchlorate with the formula (C5H8N3)ClO4abbreviated 3,4-DAPP was synthesized in aqueous solution at room temperature by the slow evaporation method. It crystallizes in the monoclinic system,with a non-centrosymmetric space group P21with the following parameters: a=5.1261 (9), b=9.3003 (17),c=8.6659 (16) Å and β=102.595 (7) °. However, the supramolecular crystal structure was built from perchlorate anions (ClO4)- and organic diaminopyridinum cations (C5H8N3)+connected with hydrogen bonds to form a three-dimensional network. Fourier transform infrared (FTIR) and Raman spectra indicate that the vibrational modes correspond to both inorganic and organic entities. According to Hirschfeld’s analysis, the crystal packing is mainly stabilizedby the presence of hydrogen bonds O⋯H (50%), as well as the crystal void analysis indicates the mechanical stability of the structure. Furthermore, the thermal behavior studied by thermogravimetric (TGA-DTA) and differential scanning calorimetry (DSC) appears to have good stability up to 280°C. Finally, the optical properties were investigated by UV-Vis absorption and photoluminescence spectroscopy along with density-functional theory DFT calculations, whichexhibit emission property, and a band gap energy of 3.9 eV.Additionally, biological activity tests revealed that 3,4-DAPP exhibited moderate antibacterial activity, particularly against Bacillus cereus, though it was less effective than 3,4-diaminopyridine (3,4-DAP) against several other bacteria, indicating that the perchlorate group in 3,4-DAPP may reduce its antimicrobial efficacy.

Wear phenomena on natural stone of the cultural heritage are induced from various sources. Consequently, the development of multifunctional protective materials which combine two or more useful properties is an effective strategy to address the synergistic effects of various wear mechanisms. A multifunctional coating, consisting of a silane-based precursor and zinc oxide (ZnO) nanoparticles (NPs), is produced and tested for the protection of limestone. The hybrid coating combines the following three properties: superhydrophobicity, including water-repellency, photocatalytic self-cleaning and biocidal activity. The relative concentration of the NPs (0.8% w/w), used for the suggested composite coating, is carefully selected according to wetting studies, colourimetric measurements and durability (tape peeling) tests. The non-wetting state is evidenced on the surface of the composite coating by the large contact angle of water drops (≈153°) and the small contact angle hysteresis (≈5°) which gives rise to the physical self-cleaning scenario (lotus effect). The photocatalytic chemical self-cleaning is shown with the removal of methylene blue, induced by the UV-A radiation. Moreover, it is shown that the suggested coating hinders the incubation of E. coli and S. aureus as the inhibition were 94.8 and 99.9 %, respectively. Finally, preliminary studies revealed the chemical stability of the suggested coating.

New antibacterial agents are needed to overcome the increasing number of infectious diseases caused by pathogenic microorganisms due to the emergence of multi-drug resistant strains. In this context, halogens, especially Iodine is known since ages for its antimicrobial activity. Therefore, especially triiodides encapsulated in organometallic complexes can be helpful as new agents against microorganisms. The aims of this work was to study the biological activity of [Na(12-Crown-4)₂]I₃ against gram positive Streptococcus pyogenes, Streptococcus faecalis, the spore forming bacteria Bacillus subtilis and gram negative bacteria Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa and Klebsiella pneumoniae, as well as the yeast Candida albicans. The antimicrobial and antifungal activities of the triiodide were determined by zone of inhibition plate studies. [Na(12-Crown-4)₂]I₃ exhibited potent antimicrobial activity on gram positive Streptochocci and the yeast C. albicans. Furthermore, the gram negative bacteria P. aeruginosa and K. pneumoniae were less effectively inhibited, while E. coli and P. mirabilis proved to be even resistant.

Staphylococcus aureus (S. aureus) is a major human pathogen that requires new antibiotics with unique mechanism. A new pleuromutilin derivative, 14-O-[(4,6-Diaminopyrimidine-2-yl) thioacetyl] mutilin (DPTM), has been synthesized and proved as a potent antibacterial agent using in vitro and in vivo assays. In the present study, DPTM was further in vitro evaluated against Methicillin-resistant Staphylococcus aureus (MRSA) isolated from dairy farms and outperformed tiamulin fumarate, a pleuromutilin drug used for veterinary. Moreover, a murine skin wound model caused by MRSA infection was established and the healing effect of DPTM was investigated. The results showed that DPTM could promote the healing of MRSA skin infection, reduce the bacterial burden of infected skin MRSA and decrease the secretion of IL-6 and TNF-α inflammatory cytokines in plasma. These results provided the basis for further in-depth drug targeted studies of DPTM as a novel antibacterial agent.

Cadmium Sulfide nanoparticle (CdS-LA hybrid nanoparticles) was synthesized here by a green approach using the precursor cadmium acetate and sodium sulphide along with the extract of a plant Lathyrus aphaca L. containing the phytochemicals which were responsible for surface modification of nanoparticles. The nanoparticle was used to evaluate their inhibition potential against species of bacteria and fungi. The nanoparticles were characterized by XRD which demonstrates the hexagonal crystal structure. SEM confirms the homogenous surface appearance of the CdS-LA hybrid crystalline structure. EDX analysis confirms surface modification of nanoparticles by phytochemicals. FTIR confirmed the Cd-S linkage laterally with the related functional groups and the presence of metabolites on the surface of nanoparticles. The UV-visible spectroscopy confirmed the peak at the characteristic wavelength range but a slight shift occurred in the peak of the CdS nanoparticles due to the presence of the phytochemicals. This study particularly provides an environment-friendly strategy to synthesize the CdS nanoparticles capped by Lathyrus Aphaca L. extract that are biologically active due to the mediation of the plant extract. CdS-LA hybrid nanoparticles have shown inhibition potential against various species of bacteria and fungi and realize the biological importance of the green synthesis of nanoparticles especially mediated with the plant extract.

Probiotics are microorganisms infused in products for health benefits including acceleration of nutrient digestion, however, it is also important to ensure the safety prior to incorporation. Here, we present evidence of the ability of two probiotic isolates,Lacticaseibacillus paracasei BCRC-16100 and Lacticaseibacillus paracasei ZFM54, in the (1) enhancement of carbohydrate digestion, (2) tolerance to stress, and (3) antibiotic resistance. Approaches include whole genome sequence (WGS) analysis and bioactivity assays. WGS revealed genes suggesting the ability of the two isolates to promote carbohydrate digestion, tolerance to stress and antibiotic resistance. Carbohydrate digestive ability was confirmed through a biochemical assay where the two isolates cause glucose release from starch. The two isolates also showed versatility in a range of temperature and alcohol concentration. For antibiotic resistance particularly on vancomycin, there are three mechanisms namely transporter control, transcriptional regulation, and efflux pump. Furthermore, promoter and transposable element analysis showed that some of the active antibiotic resistant (AbR) genes can be laterally transferred. Altogether, we show the potential of two probiotic isolates to be incorporated in products for improved carbohydrate digestion and the need to address the removal of active and mobile antibiotic resistance genes that may compromise safety.

Here we report a new synthetic protocol based on Microwave- Assisted Synthesis (MAS) for the preparation in higher yields of zinc and copper MOFs based on different bis(pyrazolyl)-tagged ligands ([M(BPZ)]n where M = Zn(II), Cu(II), H2BPZ = 4,4′-bipyrazole, [M(BPZ-NH2)]n where M = Zn(II), Cu(II); H2BPZ-NH2 = 3-amino-4,4’-bipyrazole, and [Mx(Me4BPZPh)] where M = Zn(II), x = 1; Cu(II), x = 2; H2Me4BPZPh = bis-4′-(3′,5′-dimethyl)- pyrazolylbenzene) and a detailed study of their antibacterial activity, tested against Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria, as representative agents of infections. The results show that all MOFs exert a broad-spectrum activity and strong efficiency in bacterial growth inhibition, with a mechanism of action based on surface contact of MOFs particles with bacterial cells through the so-called “chelation effect” and reactive oxygen species (ROS) generation, without a significant release of Zn(II) and Cu(II) ions. In addition, morphological changes were elucidated by using scanning electron microscope (SEM) and bacterial cell damage was further confirmed by confocal laser scanning microscopy (CLSM) test.

We report a facile route for the green synthesis of trimethylchitosan nitrate-capped silver nanoparticles (TMCN-AgNPs) with positive surface charge. In this synthesis, silver nitrate, glucose, and trimethyl chitosan nitrate (TMCN) were used as silver precursor, reducing agent, and stabilizer, respectively. The reaction was carried out in a stirred basic aqueous medium at room temperature without the use of energy-consuming or expensive equipment. We investigated the effects of the concentrations of NaOH, glucose, and TMCN on the particle size, zeta potential, and formation yield. The AgNPs were characterized by UV-visible spectroscopy, photon correlation spectroscopy, laser Doppler anemometry, transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. The catalytic activity of the TMCN-AgNPs was studied by the reduction of 4-nitrophenol using NaBH₄ as a reducing agent. We evaluated the antibacterial effects of the TMCN-AgNPs on Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus using the broth microdilution method. The results showed that both gram-positive and gram-negative bacteria were killed by the TMCN-AgNPs at very low concentration (< 6.13 μg/mL). Moreover, the TMCN-AgNPs also showed high antibacterial activity against clinically isolated multidrug-resistant A. baumannii strains, and the minimum inhibitory concentration (MIC) was ≤ 12.25 μg/mL.

A new method for the synthesis of azido-propargyloxy derivatives of 1,3,5-triazine has been developed. The antibacterial activity against E. coli bacteria of propargyloxy substituted 1,3,5-triazines - 2,4,6-trispropargyloxy-1,3,5-triazine, 2-azido-4,6-bispropargyloxy-1,3,5-triazine and 2,4-diazido-6-propargyloxy-1,3,5-triazine and their hyperbranched polymers. It has been shown that the presence of an azide group in the compound directly affects the antibacterial activity. The cytotoxicity of these compounds against the M-HeLa, FetMSC and Vero cell lines was studied. The IC50 value was determined for low molecular weight compounds. It has been shown that hyperbranched polymers without azide groups don’t exhibit pronounced cytotoxicity and can be used in biomedical applications.

Zingiber cassumunar Roxb. is a powerful medicinal plant that has been used as traditional medicine to cure respiratory problems, pain, and inflammation in China, Indonesia, Thailand and other Asian countries by using the crude extracts. The objective of this research is to identify phytochemical composition of Z. cassumunar Roxb. and to analyze antibacterial activity of crude extract, purified compounds, and their microencapsulated products of Rhizome Z. cassumunar Roxb. Identification of phytochemical composition in crude extract of rhizome Z. cassumunar Roxb. was achieved by chromatography-mass spectrophotometer. The major phytochemical composition in crude extract of Z. cassumunar Roxb. is essential oils, including terpinen4-ol (37.7%), β-pinene (20.8%), and (E)-1-(3,4-dimethoxyphenyl)but-1-ene (13.3%). Crude extract of Z. cassumunar Roxb. was purified with silica gel flash column chromatography, resulting two purified compounds. The antibacterial activity of crude extract, purified compounds, and their microencapsulated products of Rhizome Z. cassumunar Roxb. were evaluated against agricultural and foodborne pathogens by using disc agar diffusion and broth microdilution techniques. All of the samples studied (crude extracts, purified compounds, and microencapsulated of Z. cassumunar Roxb.) were effective against all the bacteria. Based on the results of the disc-diffusion assay suggested that amongst the samples studied, purified compounds (compound 1 and 2) and microencapsulated purified compounds (compound 1 and 2) exhibited more effective against all the bacteria compared to the crude extracts. Antibacterial activity of the rhizome of Z. cassumunar Roxb. was contributed mainly by the essential oils components as the active compounds. Gram-negative bacteria (X. oryzae, X. translucens, Pseudomonas spp, E. coli, and S. typhimurium) appeared to the most resistant to the crude extracts, purified compounds, and microencapsulated of Z. cassumunar Roxb. compared to the gram-positive bacteria (S. aureus, B. cereus, and L. monocytogenes). Microencapsulated of the tested samples (crude extract, purified compound 1, and purified compound 2) of the rhizome Z. cassumunar Roxb. exhibited high antibacterial activity with no significantly different with the tested samples without microencapsulation. These results suggest potential antibacterial properties of Z. cassumunar Roxb., which useful for agricultural plant health, food preservation, natural therapies, and pharmaceuticals.

Heat stress affects the yield of medicinal plants and can reduce biomass and/or metabolite production. In order to evaluate the effect of heat-induced stress on the essential oil production in Mentha x piperita L. var. Mitcham (Mitcham mint) and Mentha x arvensis var. piperascens Malinv. ex L. H. Bailey (Japanese mint), we studied the chemical composition of the oils of the two mint species under different heat shock stress in growth chambers. The antibacterial activity of the essential oils was also evaluated; microscopic observation (fluorescence and electron transmission) was used to assess the effect of the tested samples on bacterial growth. The results obtained shed light on the mint essential oils composition and biological activity in relation to heat stress.

Copper-containing materials are attracting attention as self-desinfecting surfaces, suitable for helping healthcare settings in reducing healthcare associated infections. However, the impact of repeated exposure to disinfectants frequently used in biocleaning protocols on their antibacterial activity remains insufficiently characterized. This study aimed at evaluating the antibacterial effi-ciency of copper (positive control), a brass alloy (AB+®) and stainless steel (negative control) after repeated exposure to a quaternary ammonium compound and/or a mix of peracetic acid/hydrogen peroxide routinely used in healthcare settings. A panel of 6 antibiotic-resistant strains (clinical isolates) was selected for this assessment. After a short (5 min) exposure time, the copper and brass materials retained significantly better antibacterial efficiencies than stainless steel, whatever the bacterial strain or disinfectant treatment considered. Moreover, post-treatment with both disinfectant products, copper-containing materials still reached similar levels of antibacterial efficiency as those obtained before treatment. Antibiotic resistance mechanisms such as efflux pump overexpression did not impair the antibacterial efficiency of copper-containing materials, neither did the presence of one or several genes related to copper homeostasis/resistance. In light of those results, surfaces made out of copper and brass remain interesting tools in the fight against dissemination of antibiotic-resistant strains that might cause healthcare associated infections.

The current study describes the preparation of chitosan nanoparticles (CNPs) using hydroxychloroquine (HCQ), widely used in traditional medicine due to its diverse phar-macological and medicinal uses. This work aims to combine the HCQ drug with CS NPs to generate a novel nanocomposite with improved characteristics and bioavailability. HCQ@CS NPs is roughly shaped like roadways and has a smooth surface with an average size of 159.3±7.1 nm, a PdI of 0.224±0.101, and a zeta potential of +46.6±0.8 mV. To aid in the development of pharmaceutical systems for use in cancer therapy, the binding mech-anism and affinity of the interaction between HCQ and HCQ@CS NPs and BSA were ex-amined using stopped-flow, other spectroscopic approaches, supplemented by molecular docking analysis. HCQ and HCQ@CS NPs binding with BSA is driven by a ground-state complex formation that may be accompanied by a non-radiative energy transfer process, and binding constants indicated that HCQ@CS NPs-BSA was more stable than HCQ-BSA. The stopped-flow analysis demonstrated that, in addition to increasing BSA affinity, the nano formulation HCQ@CS NPS changes the binding process and may open up new routes for interaction. Docking experiments verified the development of the HCQ-BSA complex, with HCQ binding to the site I on the BSA structure, primarily with the amino acids Thr 578, Gln 579, Gln 525, Tyr 400, and Asn 404. Furthermore, the nano-formulation HCQ@CS NPS not only increased cytotoxicity against the A549 lung cancer cell line (IC50 = 28.57±1.72 g/ml) compared to HCQ (102.21±0.67) g/ml), but also exhibited higher anti-bacterial activity against both Gram-positive and Gram-negative bacteria when compared to HCQ and chloramphenicol which in agreement with the binding constants. The nano formulation developed in this study may offer a viable therapy option for A549 lung cancer.

A facile and novel synthesis of thirteen 2-amino-3-cyanopyridine derivatives 5(a-m), by a one-pot multicomponent reaction (MCRs), is described for the first time, starting from aromatic aldehydes, malononitrile, methyl ketones, or cyclohexanone and ammonium acetate in the presence of the nanostructured diphosphate Na2CaP2O7 (DIPH) at 80 °C, under solvent-free conditions. These compounds were synthesized in short reaction times with good to excellent yields (84-94%). The diphosphate Na2CaP2O7 is used as an efficient catalyst, environmentally, easy handling, non-toxic, stable, and reusable. Our study was strengthened by the synthesis of five new pyrido[2,3-d]pyrimidine derivatives 6(b, c, g, h, j) by intramolecular cyclization of 2-amino-3-cyanopyridines 5(b, c, g, h, j), with formamide. The synthesized products were characterized by FT-IR, SEM, XRD, TEM, 1H NMR, 13C NMR, TLC, and BET. The operating conditions were optimized using a model reaction in which the catalyst amount, temperature, time, and solvent effect were evaluated. The antibacterial activity was tested against Gram-positive and Gram-negative strains for the synthesized compounds.

The emergence of superhydrophobicity-based antibacterial materials represents a promising approach to upholding surface cleanliness and hygiene, effectively preventing bacterial adhesion. This research describes the synthesis of a superhydrophobic coating with antibacterial and bacteriostatic properties using silica nanoparticles (SiO2 NPs) modified with 1H,1H,2H,2H-Perfluorodecyltriethoxysilane (PFDTES). TEM, XRD, EDS, SEM, and FTIR analyses were conducted to study its morphology and surface characterization. Additionally, the coating was applied on glass substrates using the spray coating method, varying the number of layers to evaluate antibacterial and bacteriostatic properties through turbidimetry and inhibition halo measurement techniques. The durability of the coatings was also assessed by exposing them to outdoor conditions for 35 days. This study aimed to evaluate the antibacterial capacity of the superhydrophobic coating and its weather resistance. The results demonstrate that a superhydrophobic coating with a contact angle ≥150° and a sliding angle ≤10° was successfully synthesized using SiO2 NPs smaller than 10 nm modified with PFDTES. The coating exhibited the ability to inhibit bacterial growth by preventing the adhesion of bacteria such as Escherichia coli and Staphylococcus aureus; moreover, the number of layers correlated with enhanced antibacterial properties. The coating also showed good durability under outdoor conditions. These results support the potential application of superhydrophobic coatings to prevent these bacteria from adhering and growing in areas where they can be harmful.

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.

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.

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.

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.

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.

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.

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%.

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.

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.

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.

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.

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.

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.

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.