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The capacity of Ag nanoparticles to destroy various micro‐organisms makes it one of the most powerful antimicrobial agents, an attractive feature against antibiotic resistant bacteria. Here, a simple method to develop coating of colloidal silver on paper using a biological method is presented. The coated paper was studied by scanning electron microscopy, X‐ray diffraction technique and atomic absorption spectroscopy. The antibacterial activity of the coated paper against Escherichia coli and Staphylococcus aureus was measured by agar diffusion method. This study shows the potential use of the coated paper as a food antimicrobial packing material for longer shelf life. [ABSTRACT FROM AUTHOR]

The authors report Myxobacteria virescens (M. virescens) mediated synthesis of silver nanoparticles (AgNPs) and its efficacy against Staphylococcus aureus (ATCC‐33591), Salmonella typhi (ATCC‐51812), Escherichia coli (E. coli) (ATCC‐14948), Klebsiella pneumoniae (MTCC‐4030) and Pseudomonas aeruginosa (MTCC‐4673). The organism exhibiting resistance to various antibiotics showed remarkable sensitivity, when used in combination of antibiotics and AgNPs. Antimicrobial property of AgNPs is playing a significant role in medicine and food storage. In this study, they have used M. virescens for the synthesis of AgNPs, which were characterised by using UV‐Vis spectrophotometer, nano‐particles tracking and analysis, zeta potential, Fourier transform infrared spectroscopy, X‐ray diffraction and transmission electron microscopy. Synthesised AgNPs were impregnated into paper by three different methods, i.e. glass rod method (without binder), glass rod method (with binder) and direct synthesis of AgNPs on paper. Nanoparticles synthesis on paper showed the significant antimicrobial activity against Staphylococcus aureus (ATCC‐33591), Salmonella typhi (ATCC‐51812), E. coli (ATCC‐14948), Klebsiella pneumoniae (MTCC‐4030) and Pseudomonas aeruginosa (MTCC‐4673). Paper impregnated with AgNPs was used for wrapping of fruits (apples) which increases their shelf life up to 15 days. This study demonstrates a new method for wrapping of fruits, which increases the shelf life of apples. [ABSTRACT FROM AUTHOR]

Multifunctional air filters with efficient particulate matters (PMs) removal, low respiratory resistance and prevention harmful substances are highly demanded. Bacterial cellulose (BC) air filter can capture PMs and separate them from the airflow; however, the dense network structure sacrifices the air permeability. Herein, we incorporated silver nanowires (AgNW) to BC filter through in‐situ cultivation method to prepare a new air filter. The addition of AgNW endows BC filter with antibacterial activity and increases the porosity and air permeability. Surprisingly, AgNW incorporation achieves high‐efficiency filtration through electrostatic adsorption. The filtration efficiency of the BC/AgNW composite filter paper for PM2.5 and PM10 is as high as 99.7% and 99.8%, respectively, that are on par with commonly used 3 M masks on the market. The pressure drop is 123 Pa, which can meet market demand with satisfaction. In addition, the tailor‐made BC/AgNW owns efficient antibacterial potency to keep the human body from infecting germs and other interferences. Overall, this work indicated that the versatile composite air filter paper is promising for various applications in the environmental field and the critical need for human health. [ABSTRACT FROM AUTHOR]

Tomatoes are rich in nutrients, yet they have a short shelf life and are prone to decay due to bacterial invasion. Polysaccharides extracted from Osmunda japonica (Thunb) were briefly characterised. The inhibitory effect of polysaccharides on nine kinds of common spoilage and pathogenic bacteria in tomatoes stored postharvest was studied, and the polysaccharides had broad‐spectrum antibacterial and antifungal activities against many tested strains. The minimum inhibitory concentrations (MICs) and the minimum bactericidal (fungicidal) concentrations (MBCs) were determined, and the lowest MBC against Bacillus cereus was 0.15 g L−1. Various concentrations of an O. japonica (Thunb) polysaccharide (OP) solution were sprayed onto ordinary preservation paper, which then distinctly maintained tomato freshness. OP delayed vitamin C (VC) and titratable acid decreases and increased respiratory intensity in a dose‐dependent manner, reducing malondialdehyde accumulation. The tomatoes could be stored for 30 day at 25 ± 1 °C. OP has potential as a safe, nontoxic natural plant preservative. [ABSTRACT FROM AUTHOR]

Hydrazones display an interesting profile of biological activities, which includes mainly antimicrobial and antiproliferative properties. Hydrazones also play an important role in the synthesis of heterocyclic rings and in coordination chemistry. Currently, the synthesis of complexes of hydrazones with transition metals is quite frequently reported in the scientific literature. The interest in this topic is largely due to diverse biological activities of the metal complexes of hydrazones that in some cases are much more effective than hydrazones themselves. This review focuses on the complexes of hydrazones with transition metals which display antibacterial, antitubercular, antifungal and anticancer activities. In the following subchapters devoted to a given activity, an attempt has been made to present the most active complexes of hydrazones, their trends in their activity and application in medicinal chemistry. The paper presents the literature data from 2009 to 2023. This review constitutes a useful guide for the researchers who intend to synthesize and investigate complexes of hydrazones in terms of their antimicrobial and anticancer activities. [ABSTRACT FROM AUTHOR]

A series of novel thermoplastic polyurethane elastomers with both low surface energy and antibacterial activity were synthesized in this paper. Firstly, four imidazole salt diols with different alkyl chain lengths at the N‐position of imidazolium cation ([CnIm+][Cl−]) were prepared. Then, imidazolium‐based ionic thermoplastic polyurethane elastomers (Si‐ITPUs) were formulated by incorporating polydimethylsiloxane and polytetramethylene glycol as a mixed soft segment, 1,4‐butanediol and [CnIm+][Cl−] as a chain extender, and 4,4′‐dicyclohexylmethane diisocyanate. The structure, thermal stability, mechanical properties, physical crosslinking density, and the anti‐graffiti properties of Si‐ITPUs were evaluated. The surface energy and water absorption were evaluated through static contact angle and water resistance tests, respectively. Furthermore, the antibacterial activities against both Staphylococcus.aureus and Escherichia coli were characterized by the plate colony counting method. The results demonstrated that Si‐ITPUs possessed surface energy of approximately 23 mN/m, which conferred excellent anti‐graffiti and self‐cleaning performance. Furthermore, the increase of the alkyl chain length of substitutions resulted in a decrease in the tensile strength but an increase in the elongation at break. Si‐ITPU‐C4 exhibited optimized antibacterial activities with an antibacterial rate of more than 99.9% against both S. aureus and E. coli. This novel polyurethane is anticipated to find applications in the medical device industry and food processing sector. [ABSTRACT FROM AUTHOR]

The paper presents results of the studies on porous composites obtained using lyophilization method based on the solutions of the following polymers: chitosan, sodium alginate and polylactide, as well as ZnO‐doped CaO–SiO2–P2O5 bioglass. The researchers took the advantage of zinc ions demonstrating the bactericidal, immune‐stimulating, and tissue‐regenerating functions in the organism. The cytotoxicity of the composites was tested on L929 cells by means of the direct and the indirect contact method. The antibacterial properties were determined against the gram‐negative bacteria Pseudomonas aeruginosa and the gram‐positive bacteria Staphylococcus aureus at 24, 48 hours, and 7 days. The study demonstrated that changes due to cytotoxicity effect of the composites depend on the type of polymer and on the duration of contact with cells. The composite with polylactide was found to be the least toxic for L929 cells. ZnO added to the chemical composition of bioglass ensured bactericidal effects. The antibacterial properties of the composites depended on the ZnO content, bioglass grain size, polymer type, and composite microstructure. The composites presented in this paper are innovative as biomaterials for filling bone cavities because they can be a matrix for cells and have an antibacterial effect while supporting the regeneration of damaged tissue. [ABSTRACT FROM AUTHOR]

This paper describes green, simple, and efficient method for the synthesis of magnetite nanoparticles (Fe3O4 NPs) using Acacia concinna fruit extract for the first time. A. concinna fruit extract is used as reducing and stabilizing agent. Reduction of Fe3+ ions by A. concinna fruit extract is examined by UV‐visible absorption spectra (UV‐Vis‐NIR). To recognize the functional group responsible for Fe3O4, the NPs are characterized by Fourier transform infra‐red spectroscopy (FTIR). The structural analysis of Fe3O4 NPs is done by X‐ray diffraction (XRD) which confirms cubic spinel structure and the average crystallite size of obtained NPs is found to be 28 nm. The morphological studies of Fe3O4 NPs are done by scanning electron microscope (SEM) which depicts the quasi‐spherical morphology. The green synthesized Fe3O4 NPs shows distinctive antibacterial activities against gram‐negative E. coli and Pseudomonas aeruginosa microorganism which confirms its potential in biomedical applications. [ABSTRACT FROM AUTHOR]

In this paper, an artificial nanozyme with efficient oxidase‐mimicking activity is developed to investigate antibacterial performance. The bamboo‐like nitrogen‐doped carbon nanotubes encapsulating cobalt nanoparticles (N‐CNTs@Co) are synthesized by pyrolysis of cobalt cyanide cobalt at high temperature. It is found that the oxidase‐mimicking activity of N‐CNTs@Co is higher than that of iron‐centered nanomaterials synthesized by pyrolysis of prussian blue under the same conditions, confirming that the oxidase‐mimicking activity is not only related to the active center, but also closely related to its morphology. In addition, the oxidase‐mimicking activity of N‐CNTs@Co is 12.1 times higher than that of the most reported CeO2. N‐CNTs@Co can catalyze oxygen to produce a large number of reactive oxygen species (ROS) under acidic conditions, resulting in a favorable antibacterial effect against two representative bacteria, Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli). Because the bacterial membrane is damaged by the attack of ROS, the DNA is degraded, eventually causing the bacteria to die. Antibacterial experiments last for 20 days, nevertheless, S. aureus and E. coli do not develop resistance to N‐CNTs@Co. The experiments of wound healing in vivo further confirm the high antibacterial efficiency of N‐CNTs@Co. [ABSTRACT FROM AUTHOR]

This study aimed to perform a systematic review and meta‐analysis of papers discussing the efficacy of microbial synthesised metallic nanoparticles (MNPs) against cancerous and normal cell lines by exploiting Bayesian generalised linear (BGL) model. Data was systematically collected from published papers via Cochrane library, Web of Science, PubMed, Science Direct, ProQuest, Scopus, and Embase. Impressively, most of the studies were carried out on HeLa and A549 cancer cell lines. Specifically, a hefty 65.67% of studies employed bacteria to biofabricate MNPs. Significantly, BGL meta‐analysis represented highly valuable information. Hence, based on adjusted analysis, the MNPs with the size of 25–50 nm were found to be far less cytotoxic than the MNPs with the size of ≤25 nm (OR = 0.233, P ˂ 0.05) against either cancerous or normal cell lines. Interestingly, it was found that the odds of cytotoxicity in cancerous cell lines were practically nine times more than normal cell lines, representing the substantially more cytotoxicity of MNPs in cancerous cell lines (OR = 9.004, P ˂ 0.001). Green MNPs mentioned here may be developed as novel anti‐cancer agents, which could lead to a revolution in the treatment of cancer. [ABSTRACT FROM AUTHOR]

This paper investigated the green synthesis of silver nanoparticles (AgNPs) using aqueous extract of silky hairs of corn (Zea mays L.) which is a waste material of the crop, as both a reducing and stabilising/capping agent. The AgNPs were characterised by UV‐visible spectroscopy, scanning electron microscopy (SEM), energy dispersive X‐ray analysis (EDX), thermogravimetric analysis (TGA), X‐ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT‐IR). The average size of AgNPs was found to be 249.12 nm. The AgNPs displayed strong antibacterial activity against five different foodborne pathogenic bacteria with diameter of inhibition zones ranged between (9.23 − 12.81 mm). It also exhibited potent synergistic antibacterial activity together with standard antibiotics, kanamycin (10.6 − 13.65 mm inhibition zones) and rifampicin (10.02 − 12.86 mm inhibition zones) and anticandidal activity with amphotericin b (10.57 − 13.63 mm inhibition zones). The AgNPs exhibited strong antioxidant activity in terms of nitric oxide scavenging (IC50 91.56 µg/mL), ABTS (2,2′‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulphonic acid) radical scavenging (IC50 115.75 µg/mL), DPPH (1,1‐diphenyl‐2‐picrylhydrazyl) radical scavenging (IC50 385.87 µg/mL), and reducing power (IC0.5 23.14 µg/mL). This study demonstrated the synthesis of spherical AgNPs with strong antibacterial, anticandidal and antioxidant properties that could potentially be utilised in the biomedical, cosmetic, food and pharmaceutical industries. [ABSTRACT FROM AUTHOR]

As a reactive intermediate, chloracetyl chitosan oligosaccharide (CACS) can be nucleophilic substituted by some bioactive groups to give novel derivatives of chitosan oligosaccharide (COS). The Schiff bases of pyridine‐4‐aldehyde are grafted onto CACS to give four COS derivatives in this paper. Specific structural characterization is implemented by fourier‐transform infrared spectroscopy (FTIR) and nuclear magnetic resonance (NMR). The degree of substitution (DS) of COS derivatives is quantitatively calculated by ratio of hydrogen proton integral. Their antioxidant property is evaluated using free radical scavenging assay towards 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and superoxide anion radicals, and the antibacterial activity against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) is also investigated. The results revealed that the pyridine‐4‐aldehyde Schiff bases grafted chloracetyl chitosan oligosaccharide derivatives showed better antioxidant activity as well as antibacterial activity than COS and CACS, which may be related to the positive charge of these derivatives. Among all final products, derivative BPCACS with the highest DS has the best bioactivity with scavenging rate of 91.49% for the DPPH assay and inhibition diameter of 39.25 mm for S. aureus inhibitory assay, respectively. These results indicated that COS derivatives with enhanced biological activities could serve as potential biomaterial for antioxidant and antibacterial applications. [ABSTRACT FROM AUTHOR]

Green tea extract (GTE) contains polyphenols and can play as a bioreducing and stabilizing agent. This paper describes environmentally friendly approach for synthesis of reduced graphene oxide using GTE (GTE‐rGO). The results have confirmed that biomolecules present in green tea extract not only act as bioreductant but also functionalize the surface of rGO due to hydrogen binding and π‐π stacking interactions. The 100 ppm of rGTE‐rGO showed 0.68 ppm phenols and 0.24 ppm flavones. The rGTE‐rGO was found to have highest % of 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH, 73.83 %) scavenging activity. Antibacterial activity of GTE‐rGO exhibited strong activity against Escherichia coli and Staphylococus. A cytotoxicity evaluation of GO and GTE‐rGO was carried out on fibroblast, MCF7 breast cancer and PC3 prostat cancer cells. The 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) results showed high viability loss and toxicity of GTE‐rGO against cells especially for PC3 cells. Thus, GTE‐rGO because of biomolecules present could potentially act as antioxidant, anticancer and antibacterial agent. [ABSTRACT FROM AUTHOR]

The ability of Coriolus versicolor medicinal mushroom to grow and accumulate selenium during submerged cultivation in a selenium‐fortified medium is examined in this paper. For selenium supplementation, commercial selenium yeast was used. Control, nonenriched sample and reference cultures cultivated in the medium enriched with commercial yeast Saccharomyces cerevisiae were also prepared. The mushroom demonstrated a high ability to accumulate selenium from the added source (around 970 and 1,300 µg/g of dry mycelium weight for samples enriched with selenium in a concentration of 10 and 20 mg Se/L, respectively). The addition of selenium significantly (p ≤.05) increased the biomass yield, whereas the addition of nonenriched yeast had no significant (p ≤.05) impact. Furthermore, regression analysis showed statistically significant (p ≤.05) and positive correlations between the content of Se and Fe (r =.92), Se and Cu (r =.92), Se and Mn (r =.98), and Se and Sr (r =.96), suggesting that selenium incorporation was followed by incorporation of these elements, and led to mineral enrichment of the obtained mycelium. Methanol extracts prepared from mycelium biomass demonstrated a better inhibitory effect on Gram‐positive bacterial strains with minimal inhibitory concentrations between <0.3125 and 40 mg/ml. The obtained results showed that selenium yeast could be used for obtaining a potential novel food supplement: mushroom biomass with high selenium content and enhanced mineral composition. [ABSTRACT FROM AUTHOR]

The present paper describes the chemical oxidative polymerization of pyrrole and methyl anthranilate, Ppy-MA, in different molar ratios in high yields. The polymerization takes place in the presence of H 2O2 and FeSO4. Subsequently, electrically conducting nanocomposites Ppy-MA/TiO The present paper describes the chemical oxidative polymerization of pyrrole and methyl anthranilate, Ppy-MA, in different molar ratios in high yields. The polymerization takes place in the presence of H2O2 and FeSO4. Subsequently, electrically conducting nanocomposites Ppy-MA/TiO The present paper describes the chemical oxidative polymerization of pyrrole and methyl anthranilate, Ppy-MA, in different molar ratios in high yields. The polymerization takes place in the presence of H2O2 and FeSO4. Subsequently, electrically conducting nanocomposites Ppy-MA/TiO The present paper describes the chemical oxidative polymerization of pyrrole and methyl anthranilate, Ppy-MA, in different molar ratios in high yields. The polymerization takes place in the presence of H2O2 and FeSO4. Subsequently, electrically conducting nanocomposites Ppy-MA/TiO2 were obtained by in situ chemical oxidative polymerization using TiO 2 nanoparticles in different molar ratios. The structure and morphology of black powdered copolymers, Ppy-MA, and their nanocomposites, Ppy-MA/TiO 2, were ascertained using Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, transmission electron microscopy, X-ray differential, thermogravimetric analysis, and differential thermal analysis. These studies have shown that the nanocomposites, Ppy-MA/ TiO2, are thermally more stable, good electrical conductors as compared with their copolymers Ppy-MA. The copolymers Ppy-MA prepared from different monomer ratios and its nanocomposites Ppy-MA/TiO2 have been screened for their possible in vitro antibacterial activity against Staphylococcus aureus (ATCC 29213), Streptococcus mutans (ATCC 25175), Streptococcus pyogenes (MTCC 435), Staphylococcus epidermidis (MTCC 435), Bacillus cereus (MTCC 430), Corynebacterium xerosis (ATCC 373), Acetobacter bovis (Clinical isolate), Escherichia coli (ATCC 25922), Klebsiella pneumoniae (MTCC 109), Proteus vulgaris (MTCC 426), and Pseudomonas aeruginosa (MTCC 424) using ciprofloxacin and gentamicin as standard drugs. Moreover, the anthelmintic activities of copolymers Ppy-MA and its nanocomposites Ppy-MA/TiO 2 have also been estimated against the standard drug, albendazole. [ABSTRACT FROM AUTHOR]

This study aims to examine employing ultrasound‐assisted extraction of bioactive components from Moringa oleifera leaves and apply them in beef patties preservation, as well as antioxidant and inhibitory activities and sensory qualities. The study included studying the chemical content and minerals of the M. oleifera leaves, preparation of aqueous and alcoholic extracts using an ultrasound device, then exploring the extraction yield. The results proved that the extraction yield by ultrasound using ethanol at 80% was the highest, reaching 19.22%. The total phenols in the ultrasonic extract with moringa leaves aqueous extract (AMEUS) amounted to 120,755 mg/mL. Since the AMEUS exhibited the highest value of 68.308 mg/mL calic acid – eight phenolic compounds discovered by HPLC – the total content of flavonoids was also calculated. The inhibitory and antioxidant effects of moringa leaf extracts are well documented. We monitored the changes in chemical indicators, such as the value of peroxide and thiobarbituric acid, as well as the percentage of free fatty acids and physical characteristics, such as water‐carrying capacity, pH, and pigments, for storage periods 0, 4, 8, and 12 days after adding AMEUS to beef patties at a concentration of 0.5%. The patties were kept under refrigeration at 4 ± 1°C during this time. The values of peroxide number, thiobarbituric acid, free fatty acid, and metmyoglobin pigment were decreased in the beef patties treated with the AMEUS. However, they increased continuously during the cryopreservation period, and there was a significant increase in water‐holding capacity (WHC) when the beef patties were treated with AMEUS. The results also showed that adding AMEUS to beef patties improved their qualitative characteristics. [ABSTRACT FROM AUTHOR]

To study the antibacterial efficacy of metallic Ag nanoparticle/titania (Ag‐NP)/TiO2 composite thin films against Escherichia coli (ATCC 25922), COMP‐Agn with various amounts of Ag (10 mol% ≤ n ≤ 80 mol%) are fabricated on a quartz glass substrate at 600 °C using the molecular precursor method. The films are characterized by X‐ray diffraction, X‐ray photoelectron, scanning electron microscopy, transmission electron microscopy, photoluminescence, and UVvis techniques. The analysis reveals that the films are composed of metallic Ag‐NPs embedded in a mixture of anatase and rutile matrix, with a volumetric fraction of Ag ranging from 0.18 to 0.68. The antibacterial activity of the TiO2 thin film and COMP‐Agn are determined by disk diffusion and viable cell count methods. Neither pure TiO2 nor pure Ag films exhibit any discernible antibacterial under dark and visible light. The antibacterial of Ag content in composite films is observed to persist for a maximum increase of 70%. The model is proposed on the basis of photoexcited electron transfer from Ag NPs to the TiO2 conduction band of COMP‐Agn, which clarifies the main factors affecting the photoresponse and the excellent response to visible light via surface plasmon resonance. [ABSTRACT FROM AUTHOR]

BACKGROUND The ability of Coriolus versicolor medicinal mushroom to accumulate and transform selenium from selenourea and sodium selenite into an organic form – l‐selenomethionine – during growth in liquid medium is examined in this paper. Additionally, the impact of supplementation on biological activity of the selenated mushroom methanol extracts, as well as their chemical composition, is studied. RESULTS: Selenium accumulation was more efficient with sodium selenite application, but biomass yield was significantly lower (1.89 g DW L−1) compared to samples enriched with selenourea (4.48 g DW L−1). Mushroom sample obtained after growing in liquid medium with selenourea had significantly higher l‐selenomethionine content compared to the sample grown in medium with sodium selenite. Selenium‐enriched methanol extracts of C. versicolor mushroom showed improved antimicrobial and antioxidant activities compared to non‐enriched extract. CONCLUSION: Our results suggest that C. versicolor mushroom cultivated in liquid culture enriched with selenourea can be used for the production of novel food supplements with improved selenium bioavailability. More than 30% of total accumulated selenium from selenourea is transformed into l‐selenomethionine. Differences in biological activity of methanol extracts can be explained not only by different selenium content but also by the differences in chemical composition of extracts. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

In this paper, nanostructured silver-doped zinc oxide (Ag-ZnO) coating was prepared on Mg-2Ca-0.5Mn-6Zn alloy surface with improved corrosion resistance and antibacterial activity through physical vapor deposition (PVD). Microstructural analysis showed that the Ag-ZnO coating was adherent to the substrate with a thickness and particle size of 1 µm and 85 nm, respectively. The nanostructured Ag-ZnO coated specimens exhibited lower corrosion current density ( icorr), and higher charge-transfer resistance ( Rct) compared with the uncoated Mg alloy. Antimicrobial examination demonstrated that the Ag-ZnO coated specimen revealed a significantly better antimicrobial performance toward Escherichia coli and Staphylococcus aureus compared to the uncoated sample. The results also showed that the Ag-ZnO coating considerably reduces the corrosion rate and improves antimicrobial performance of the Mg alloy substrate. [ABSTRACT FROM AUTHOR]

This work reports the preparation of multiwalled carbon nanotube/pramipexole/Ag (CNT/pra/Ag) as a novel antibacterial agent, in which pramipexole groups are utilized as linkers to secure Ag nanoparticles to carbon nanotube surfaces without agglomeration. The resulting CNT/pra/Ag sample was characterized by performing transmission and scanning electron microscopy, wavelength- and energy-dispersive X-ray, X-ray diffraction, Fourier transform infrared, inductively coupled plasma and Raman measurements. Using this approach, monodisperse spherical Ag nanoparticles in CNT/pra/Ag have narrow size distributions with average diameters of ca 3-8 nm. The antibacterial activity of CNT/pra/Ag was investigated against bacterial species Staphylococcus aureus, methicillin-resistant S. aureus, Pseudomonas aeruginosa and Escherichia coli using the paper-disc diffusion method and by determining the minimal inhibitory concentration. CNT/pra/Ag showed better inhibitory activity towards Gram-positive bacteria than Gram-negative bacteria in this study, which indicates its potential as an antibacterial material for laboratory and medical purposes. [ABSTRACT FROM AUTHOR]

The Cu3.96Ag0.04 nanoparticles were synthesized using the essence of Foeniculum vulgare Mill for the first time. The particles were fully analysed by conventional characterization methods such as powder X‐ray diffraction (PXRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), dynamic light scattering (DLS). The results have shown the crystal structure of silver copper particles and the crystallite size obtained by the Scherer equation was 23.2 nm. The TEM images interestingly displayed the formation of nanorods in the solid phase with nearly 5 nm widths and different lengths up to 100 nm. The hydrodynamic size is also compatible with the solid phase and crystallite sizes. Biologically, the particles were tested against infective gram negative and gram positive bacteria. The synthetic NPs show strong antibacterial properties against gram negative bacteria. Also, the synthesized nanoparticles had an inhibitory effect on the growth of cancer cells, which was dose‐ and time‐dependent. [ABSTRACT FROM AUTHOR]

An efficient access to a novel series of organophosphorus compounds with a cyclosulfamide moiety is described. Starting from α‐hydroxyphosphonates, the 2‐chloroethyl‐(1, 2, 5‐ thiadiazoline‐2‐carbonyloxy‐1‐ dioxide) phosphonates compounds were prepared in three steps including an Abramov reaction, carbamoylation‐sulfamoylation with chlorosulfonyl isocyanate and an intramolecular cyclisation. The spectroscopic methods (1H NMR, 13C NMR, 31P NMR, MS and IR) were used to determine the structural characteristics of the synthesized compounds and X‐ray crystallographic data were provided for compound 3c. Some selected compounds were screened in vitro for their antimicrobial activity against a panel of microorganisms, resulting in a good antibacterial activity compared to standard drugs. [ABSTRACT FROM AUTHOR]

Summary: Most of the work on pomegranate antioxidant and antibacterial activity has been carried out with solvent extracts of different plant or fruit parts. Biosensitive compounds in juice may be subject to oxidation, reducing their biological activities. Microencapsulation can be used to protect compounds, allowing its incorporation into functional foods. This study aimed at investigating antioxidant activity after in vitro digestion of microencapsulated juice. Pomegranate juice was encapsulated by spray drying its maltodextrin and gum arabic. The average diameter of the microcapsules was 10–50 µm. We evaluated the bioaccessibility of microencapsulated phenolic compounds by using an in vitro enzymatic digestion. The total phenolic content in digested microencapsulated juice was three times greater than in undigested, indicating that the compounds were made bioaccessible. Digestion also increased antioxidant activity, as measured by ABTS●+ or by DPPH●. Additionally, microencapsulated pomegranate juice showed antibacterial activity against the nine bacteria species tested. [ABSTRACT FROM AUTHOR]

Candesartan Cilexetil (CC) is a prodrug of candesartan and an angiotensin II receptor antagonist. It is used as a drug for different diseases like myocardial infarction, hypertension, and heart failure. The applicability of CC is impeded due to its poor water solubility, low permeability, and low bioavailability. This study is targeted to improve the efficacy and bioavailability of CC by its delivery through MeO‐PEO5K‐PCL micelles. The effect of length of hydrophobic block (PCL) on size of the micelles, drug encapsulation efficiency, and drug release behavior is evaluated. MeO‐PEO5K‐PCL based micelles were prepared by solvent evaporation method. The size of PMs was determined by dynamic light scattering, morphology by atomic force microscopy, and critical micelles concentration by fluorescence method. Encapsulation efficiency and drug release behaviors of MeO‐PEO5K‐PCL based PMs were evaluated by UV‐visible spectroscopy and dispersion method, respectively. The size of micelles increased and drug release rate decreased with increase in the length of PCL block. Maximum encapsulation efficiency of 96.42 % for CC is achieved with ABCs having equal PEO and PCL block lengths. A comparison of antibacterial activity of CC in pure form and encapsulated in PMs against MRSA is conducted. The MIC50 for CC loaded PMs has decreased to more than half in comparison to pure drug. AFM based morphological analysis also confirmed the decrease in MIC50 by delivery through PMs. [ABSTRACT FROM AUTHOR]

The yellow‐legged hornet, Vespa velutina nigrithorax, is an invasive social wasp found in temperate regions and is recognized as a hazardous insect, as it often attacks humans and honeybees. Nidus vespae (nests of social wasps) are traditionally used as a medicinal ingredient; thus, V. v. nigrithorax may be useful as a biological resource. Extracts of Nidus vespae built by V. v. nigrithorax were examined for their antibacterial activity screening against six food‐borne pathogenic bacteria, and the ethyl acetate and butanol layer of the extract exhibited inhibitory activity against the pathogenic bacteria. We determined the antibacterial activity of Nidus vespae built by V. v. nigrithorax for the first time. [ABSTRACT FROM AUTHOR]

Post-surgery microbial infections are still one of the main reasons for implant failure, which results in very high physical and psychological pain for the patient and an increased cost for the healthcare system. A polymer nanocomposite antibacterial coating on titanium implants represents a valuable alternative to the more expensive and energy-consuming technological solutions nowadays used. In this regard, a sprayable thermoset nanocomposite composed of silanized-terminals polyethylene glycol (PEG)/ZnO nanoparticle is herein proposed. Initially, PEG’s terminals’ solvent-free silanization and curing are studied by Fourier Transform Infrared and μRaman spectroscopies. Scanning Electron Microscope investigations and scratch tests have shown that the spraying procedure optimization and the oxidation treatment of the titanium substrate lead to a homogeneous coverage and improved adhesion of the coatings. The antibacterial activity is tested against not only both S. aureus and P. aeruginosa bacterial American Type Culture Collection strains, but also using very aggressive antibiotic-resistant clinical strains. Interestingly, antibacterial activity, evaluated by time-killing tests, is observed for all tested bacterial strains. Live/dead tests further confirm that 5 wt% of ZnO allows obtaining a bacteriostatic activity within 24 h, whereas a complete growth inhibition (bactericidal activity) of both tested strains is observed for coatings with 20 wt% of ZnO nanoparticles. [ABSTRACT FROM AUTHOR]

The growing demand for high food quality has been encouraging researchers in the food industry to apply biodegradable nanocomposites, which provide new opportunities and challenges for the advance of nanomaterials in the food industry. The objective of this study was to estimate the antibacterial activity and cytotoxicity effects of zinc oxide nanocomposite/zeolite (c/Zeo) with Aloe vera gel (AG) and its effect on the shelf life of chicken meat. The ZnONPs/Zeo was assessed using X‐ray fluorescence (XRF) and field emission scanning electron microscopy (FE‐SEM) analyses. The cytotoxicity effect of ZnONPs/Zeo was assessed by MTT assay. Then, the minimum inhibitory concentrations (MIC) and minimum bactericidal concentration (MBC) of ZnONPs/Zeo and ZnONPs/Zeo‐AG against Salmonella typhi and Salmonella para typhi A were investigated. Also, the preservative effect of nanocomposites on chicken fillets was evaluated. The results showed that these nanocomposites have the least cytotoxicity effect, resulting in good biocompatibility with the host. The MIC and MBC values of ZnONPs/Zeo‐AG were lower than the ZnONPs/Zeo against S. typhi and S. paratyphi A. Both ZnONPs/Zeo‐AG and ZnONPs/Zeo caused a significant decrease in the bacterial count of the chicken fillets. So, by spraying on meat, the number of bacteria presented a sharper decline as compared with the control group, resulting in an approximately 3.3 and 3‐log10 reduction over 48 h in the ZnONPs/Zeo‐AG and ZnONPs/Zeo treatment samples, respectively. In conclusion, antimicrobial packaging with ZnONPs containing A. vera is a beneficial solution for preserving and improving the quality, safety, and shelf life of fresh meat products. [ABSTRACT FROM AUTHOR]

The antibacterial activity of zinc oxide nanoparticles prepared by sonication method was evaluated in this paper. Effect of calcination conditions on the size and antibacterial activity of zinc oxide nanoparticles was investigated. Zinc oxide nanoparticles were characterised for purity (Thermo Gravimetric Analyzer), crystallinity and crystal size (XRD), particle size and morphology (TEM), etc. Results showed that the smallest size 8 nm could be obtained. The lethal experiments of nanocrystalline zinc oxide were evaluated on Lactobacillus plantarum. All L. Plantarum were killed after 24-h exposure at 1000 ppm. With the increase in calcination time, the lethal effect of ZnO nanoparticles was increased after 6-h exposure at 100 or 1000 ppm. [ABSTRACT FROM AUTHOR]

The present paper reports on the preparation and characterization of potential edible packaging films based on the combination of chitosan and Piper betle Linn. leaf extract (PBLLE). The incorporation of PBLLE was found to improve important characteristics of the chitosan film, making it ideally suitable for active packaging applications. In particular, the blend films exhibited very strong inhibitory activities against both gram‐negative and gram‐positive bacteria such as Bacillus subtilis and Salmonella Typhimurium. Moreover, IC50 values of the blend films were recorded at low levels (10.63‐ 22.81 μg/mL) in the PBLLE range of 1–3% v/v. Both antimicrobial and antioxidant activities of the blend films increased with increasing incorporated PBLLE content (from 1 to 3% v/v) taking into account the activities of polyphenolic compounds contained in the extract. Compared to the pure chitosan film, a significantly lower swelling degree, higher resistance to water vapor permeation and desired flexibility were recorded for the films with sufficient extract content. Interestingly, no considerable difference in the thermal stability of the pure chitosan and the blend films was detected in thermal analysis. In addition, effects of PBLLE on other mechanical and optical properties of the blend films were also examined in detail. [ABSTRACT FROM AUTHOR]

Bacterial infection caused by medical material is a common problem in the field of medicine. In this work, we aim to develop a novel antimicrobial bioplastic with potential medical value. A novel composite material composed of polyamino acid (PAA) and titanium dioxide/silver nanoparticles (TiO2/Ag NPs) was synthesized by in situ melting polycondensation with different TiO2/Ag loadings. The morphological, antibacterial, mechanical, thermal, and cytotoxicity properties of the PAA/TiO2/Ag composites were investigated. The results showed that uniform nanocomposites with amide bonds were synthesized, and the nanocomposites with 10% TiO2/Ag incorporation exhibited the best thermal and mechanical properties. Cytotoxicity assay showed that the composites significantly promoted the proliferation of MG‐63 cells. The composites showed obvious inhibitory effect on both Escherichia coli and Staphylococcus aureus, and this effect was increased as the TiO2/Ag NPs doping was increased. These PAA/TiO2/Ag composites are suitable for antibacterial and high‐performance biomaterials in the medical field. [ABSTRACT FROM AUTHOR]

In this study, green synthesis of titanium nanoparticles using liquids metabolites of microalgae, Porphyridium cruentum, was performed to evaluate potential biotechnological activity. The rising rates of multidrug‐resistant bacteria and the number of cancer patients are driving the search for novel antimicrobial and anticancer agents to combat this threat. In recent years, with the increasing number of studies, nanomaterials are starting to be better understood and are emerging as a solution to this problem. Especially, green synthesized nanoparticles with anticancer, antioxidant, and antimicrobial activities have potential in biomedical applications because of their eco‐friendly and biocompatible nature. Scanning electron microscopy (SEM) images revealed that spherical shaped Ti‐NPs' size ranged from 62 to 133 nm. This study aimed to assess the effectiveness of antibacterial activity of Ti‐NPs and chitosan‐coated Ti‐NPs against Escherichia coli and Staphylococcus aureus using disc diffusion assay. It demonstrated the concentration‐dependent cytotoxic effect of Ti‐NPs of human prostate adenocarcinoma (PC‐3), human alveolar adenocarcinoma (A549), and human mammary gland adenocarcinoma (MDA‐MB) cancer cell lines. This present study shows promising outcomes for possible future applications of synthesized Ti‐NPs as a novel antibacterial and cytotoxic agent for biomedical applications such as drug delivery, biosensor, and hyperthermia. [ABSTRACT FROM AUTHOR]

Copper nanoparticles have been utilized in a variety of therapeutic applications because of their inexpensive manufacturing and unique characteristics. In the current study, novel nanocomposites are developed to carry bioactive agents in a controlled manner. Copper nanoparticles (Cu‐NPs) were synthesized from copper sulfate using a leaf extract of Phyllanthus virgatus as a reducing agent. The obtained Cu‐NPs are loaded into the polymeric matrix of sodium alginate and locust bean gum to generate microbeads. The developed microbeads were characterized by Fourier‐transform infrared (FTIR), X‐ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and scanning electron microscope (SEM). Swelling and in vitro release studies were performed at pH 2.0 and 7.4 at 37 °C. Metronidazole (MTD) was used as a model agent, and the antibacterial activity of microbeads was tested against Streptococcus mutans, Klebsiella pneumoniae, and Bacillus subtilis. The release kinetics and MTD release pattern were analyzed by employing the MTD release data into Korsmeyer‐Peppas equation and other kinetic models. [ABSTRACT FROM AUTHOR]

Novel bio‐fabricated ZnO nanoparticles were made from the solution of zinc nitrate in the presence of bio‐components of Jasminum grandiflorum L. The bio‐fabricated ZnO nanoparticles, represented as Jg‐ZnO NPs, were suitably characterized by several state‐of‐the‐art tools. The UV‐Vis absorption band at λmax=370 nm and the characteristic XRD peaks at appropriate positions suggest the formation of ZnO NPs. The XRD pattern revealed the formation of highly crystalline, hexagonal phase and impurity free Jg‐ZnO NPs. The presence of biomolecules on the surface of ZnO NPs was confirmed by FTIR spectral analysis. These NPs have hexagonal structures and flake‐like morphology as revealed by their TEM and SEM analysis, respectively. Further, the Jg‐ZnO NPs exhibit excellent photocatalytic activity against the MB dye under sunlight with a dye degradation efficiency of 99.8 %. Besides, the Jg‐ZnO NPs were also remarkably effective in inhibiting the growth of gram‐positive (S. aureus) as well as gram‐negative (P. aeruginosa and K. pneumoniae) pathogenic bacteria. [ABSTRACT FROM AUTHOR]

The flexible biodegradable polymer hydrogels have attracted increasing attention in the exploration of multifarious biomedical applications. However, conveniently achieving the synergistic characteristics of favorable mechanical performance, anti‐swelling behavior, antibacterial activity and conductivity into a biodegradable hydrogel remains a significant challenge. In this aspect, we report a facile one‐pot approach to prepare the multiple‐crosslinked PVA (PVA/PA‐Fe) hydrogels assisted by phytic acid (PA) and ferric trichloride. Firstly, PVA polymer chains and PA molecules form hydrogen bonds, meanwhile PA molecules interact with Fe3+ ions by ionic coordinations. Then, PVA polymer chains are crystallized by forming hydrogen bonds after cyclic freeze–thaw process. Based on the synergistic interactions of multiple hydrogen bonds and ionic coordinations in hydrogel system, PVA/PA‐Fe hydrogels possess favorable tensile strength (1222.72 kPa), toughness (1.82 MJ/m3) and anti‐swelling properties. Moreover, the introduction of PA and ferric trichloride successfully endows hydrogel with outstanding antimicrobial activity. Furthermore, the existence of H+ ions ionized by PA, Fe3+ and Cl− ions originating from ferric trichloride provides hydrogel with ionic conductivity (4.91 S/m) and strain responsiveness. Thus, the facile one‐pot preparation approach basing on the multiple‐crosslinked strategy would broaden the path for preparation of multifunctional hydrogels with promising biomedical applications, particularly smart flexible strain sensors. [ABSTRACT FROM AUTHOR]

In the current work, reduced graphene oxide (rGO) layers (20, 40, 60, and 80 mg) are decorated over the surface of copper oxide (CuO) nanoparticles using a simple and in‐situ hydrothermal reduction method. The notable variation in the XRD peak intensity of CuO:rGO samples indicates the formation of nanocomposite. HRTEM and FESEM analysis reveal a nanoplate‐like morphology with uniform particle distribution. Further, the nanocomposites are characterized using FTIR, DRS UV Visible, and XPS techniques. Here, multi‐functional applications of the synthesized nanocomposites are investigated through photocatalytic dye degradation, antimicrobial, and electrochemical sensing analyses. The photocatalytic activity of synthesized CuO:rGO nanocomposites with hydrogen peroxide (H2O2) showed higher efficiency (98 %) than pure CuO. The effects of pH, various scavengers, and different dyes on the degradation efficiencies of CuO:rGO nanocomposites are also investigated. Using the agar well diffusion method, these nanocomposites exhibited a zone of inhibition value of 32 mm against both gram positive (Bacillus subtilis) and gram negative (Escherichia coli) bacterial strains when compared to pure rGO and CuO nanoparticles. Also, nanocomposites are found to be suitable for non‐enzymatic glucose sensing with a detection limit in the range from 0.05 to 4 mM, as evidenced from the cyclic voltammetry (CV) analysis. [ABSTRACT FROM AUTHOR]

This research aims to fabricate a potent pH‐sensitive double network sodium alginate/chitosan hydrogel cross‐linked by calcium chloride (CaCl2) and glutaraldehyde for the controlled release of amoxicillin (AMX) to mitigate gastrointestinal tract bacterial infection. The effect of polymer ratios and CaCl2 concentration is investigated by the developing porosity, gel fraction, and swelling ratios in simulated physiological fluids of different pH and in vitro biodegradation at pH 7.4. Interaction between the polymers with the formation of cross‐linked structures, amorphous phase nature, good thermal stability, and transition from porous, fibrous structures to highly densified structures of the hydrogels is revealed by scanning electron microscopy, Fourier‐transform infrared spectroscopy, x‐ray diffraction, and thermogravimetric analysis. Based on structure–property relationships, a sodium alginate/chitosan hydrogel (weight ratio 75:25) cross‐linked with 2% CaCl2 and soaked in 2% (25 wt/v% solutions) glutaraldehyde is chosen for the incorporation of 200 mg of the drug. The percent cumulative AMX release in physiological fluids and the drug release kinetics using different models reveal that the most appropriate Korsmeyer–Peppas model suggests AMX release from the matrix follows diffusion coupled with swelling‐regulated time‐dependent non‐Fickian transport process related to hydrogel erosion. Excellent antibacterial against Streptococcus pyogenes and Escherichia coli is exhibited by this composition. [ABSTRACT FROM AUTHOR]

Rifampicin (RFP) is a first‐line drug used to treat a variety of infections, including wound infections but has limitations in its use due to its toxicity. Hence, an urgent need exists for the development of suitable carriers for the delivery of the antibiotic. In this study, a novel approach is introduced for drug administration, employing stimulus‐responsive carriers to achieve an on‐demand strategy. This innovative method aims to minimize the dosage and frequency of drug administration, consequently lowering cytotoxicity levels. We used the lipases‐sensitive polycaprolactone (PCL) to produce nanocomposites loaded with rifampicin (PCL−RFP NPs). Nanoparticles were prepared by a single‐step emulsion solvent evaporation method. The size distribution of blank nanoparticles (PCL NPs) and PCL−RFP NPs were 172±30 nm and 229±58 nm, respectively. The liberation of RFP from PCL−RFP NPs was monitored over a period of 72 h in the absence and the presence of lipase was 9.46±0.24 % and 53.3±3.33 %, respectively, indicating responsive behavior. The minimum inhibitory concentration to lipase‐expressing Staphylococcus aureus (S. aureus) of PCL−RFP NPs was significantly improved compared to the free drug. Cytotoxicity tests using human dermal fibroblasts showed that the nanocomposites had better biocompatible when compared to the free drug. These findings indicate that the developed nanocomposite carriers have the potential to be promising candidates for delivering antibiotics in the field of biomedicine. [ABSTRACT FROM AUTHOR]

Antibiotic resistance is rising across the world. For a very long time, bitter ginger (Zingiber zerumbet) has been used as one of the most popular herbal remedies to treat a wide range of common diseases. Ginger has been shown to have antioxidant and antibacterial activity. It has various bioactive chemicals that might be utilized as an alternative treatment option for many infectious diseases. The present study aimed to examine the biochemical profile of ginger, antioxidant, and antibacterial activity against selective endodontic microbes. Antioxidant was measured using DPPH and antibacterial activity was performed using disk diffusion tests. Streptococcus mutants, Enterococcus faecalis, Staphylococcus spp., and Lactobacillus spp. were tested for antibacterial activity. Before evaluating the dried extracts, all solvents were eliminated using rotary evaporation. The obtained IC50 value revealed that ethanol extract had the greatest antioxidant activity. Concerning each bacterium, the plant extracts demonstrated considerable antibacterial activity (p =.001). Ethanol extracts showed the strongest antibacterial activity against the studied microorganisms. This study highlights that the Zingiber zerumbet (Z. zerumbet) is a strong antibacterial herb against multidrug‐resistant (MDR) gram‐positive bacteria. It may also be employed as a possible natural antioxidant source. [ABSTRACT FROM AUTHOR]

Summary: The use of honey as a food and a medicine date back to prehistoric times. Uses include treating wounds, cuts, burns, coughs and colds. The antioxidant and antibacterial properties of honey are believed to be responsible for its medicinal properties. Honey is usually processed before consumption. Honey is subjected to thermal processing, which adversely affects its quality. Honey can also be processed by non‐thermal methods, such as high‐pressure processing, ultrasonication, irradiation and microwave processing. In this review, the effects of thermal and non‐thermal processing methods on the antioxidant and antibacterial properties of honey have been summarised. Thermal processing and microwave processing of honey adversely affect the antioxidant and antimicrobial activities of honey. In contrast to other non‐thermal processing methods, high‐pressure processing and gamma irradiation have no effect on the antibacterial activity or antioxidant properties of honey. Ultrasound processing increases antioxidant activity of honey. [ABSTRACT FROM AUTHOR]

In this study, polycaprolactone (PCL), as a biocompatible polymer was functionalized by addition of medicinal plant extract‐ Achillea millefolium L. (yarrow). Nanofiber mats were fabricated from PCL solutions containing dry yarrow extract in four concentrations (5%, 10%, 15%, and 20% relative to the weight of the polymer) by using blend electrospinning method. The nanofibers were characterized for their biological, mechanical and drug release behavior. In vitro release of yarrow polyphenols from the electrospun PCL nanofibers over a period of 5 days showed the release of up to 98% of the total loaded polyphenols. The released polyphenols retained its antioxidant activity, which was determined by DPPH assay. Electrospun PCL/yarrow nanofiber mats exhibited the antibacterial effect against Staphylococcus aureus, but had no effect on the growth of Pseudomonas aeruginosa. All PCL/yarrow nanofiber mats had improved mechanical properties compared to the neat PCL nanofibers, as evident by an increase in Young's modulus of elasticity (up to 5.7 times), the tensile strength (up to 5.5 times), and the strain at break (up to 1.45 times). Based on our results, yarrow‐loaded PCL nanofiber mats appeared to be multi‐functional biomaterials suitable for the production of catheter‐coating materials, patches, or gauzes with antibacterial and antioxidant properties. [ABSTRACT FROM AUTHOR]

Polymer nanocomposite samples of a polyvinyl alcohol (PVA)/carboxymethyl cellulose (CMC) blend doped with copper nanoparticles and selenium nanoparticles (Cu NPs/Se NPs) were prepared by the casting method. X‐ray diffraction analysis (XRD) patterns showed an increase in the degree of amorphous nature of the host polymeric matrix with increasing content of Cu/Se nanoparticles. The addition of 1.60 wt.%, Cu/Se NPs narrowed the indirect optical energy gap value of the nanocomposite from 3.97 to 2.39 eV. In addition, the differential scanning calorimetry (DSC) curve of the pure blend displays the miscibility of the blend components, confirmed by the presence of a single glass transition. Transmission electron microscopy (TEM) micrographs showed that the average sizes of Cu and Se nanoparticles are about 11 and 41 nm, respectively. The maximum values of AC and DC conductivity were 6.76 × 10−6 S.cm−1 and 5.49 × 10−10 for a PVA/CMC film filled with 1.60 wt.% of Cu‐Se NPs. The mechanical properties of the PVA/CMC blend improved after adding the hybrid NPs. Moreover, the antibacterial activity of the prepared samples was increased due to the filling of Cu‐Se nanoparticles to the films. Therefore, these results indicate the multifunctionality of PVA/CMC/Cu‐Se nanocomposite samples for use in electrical energy storage, solid‐polymer electrolytes, and food packaging industry. [ABSTRACT FROM AUTHOR]

Pithecellobium dulce leaf extract was used to synthesize gold nanoparticles (AuNPs) for the first time. This bio‐synthesized novel material was investigated by UV‐visible spectra, high‐resolution transmission electron microscopy, powder diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy‐dispersive analysis by X‐ray. Excellent antibacterial activity was revealed against Staphylococcus aureus and Escherichia coli. Significant antifungal activities by the AuNPs were also demonstrated. The analysis of AuNPs by 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide (MTT) assay proved 100 % toxic effect and the minimum value of half‐maximal inhibitory concentration (IC50) indicates that it is safe to be used as drug in the medical field. [ABSTRACT FROM AUTHOR]

Inside the biological milieu, nanoparticles with photocatalytic activity have potential to trigger cell death non‐specifically due to production of reactive oxygen species (ROS) upon reacting with biological entities. Silver nanoparticle (AgNP) possessing narrow band gap energy can exhibit high light absorption property and significant photocatalytic activity. This study intends to explore the effects of ROS generated due to photocatalytic activity of AgNP on antimicrobial and cytotoxic propensities. To this end, AgNP was synthesized using the principle of green chemistry from the peel extract of Punica granatum L., and was characterized using UV–Vis spectroscope, transmission electron microscope and x‐ray diffraction, and so forth. The antimicrobial activity of AgNP against studied bacteria indicated that, ROS generated at AgNP interface develop stress on bacterial membrane leading to bacterial cell death, whereas Alamar Blue dye reduction assay indicated that increased cytotoxic activity with increasing concentrations of AgNP. The γH2AX activity assay revealed that increasing the concentrations of AgNP increased DNA damaging activity. The results altogether demonstrated that both antimicrobial and cytotoxic propensities are triggered primarily due interfacial ROS generation by photocatalytic AgNP, which caused membrane deformation in bacteria and DNA damage in HT1080 cells resulting in cell death. [ABSTRACT FROM AUTHOR]

BACKGROUND: Natural products play a significant role in the development of novel bactericide candidates. Caesalpinia pulcherrima, a traditional medicine, had anti‐inflammatory, antimicrobial, and antifeedant activities, therefore the previous bioassay results of C. pulcherrima implied that its main active ingredients may have potential to be used as botanical bactericides. RESULTS: Bio‐guided isolation of C. pulcherrima was conducted to obtain 11 novel cassane diterpenoids (capulchemins A–K) and 10 known sesquiterpenes. Their structures were established by extensive spectroscopic methods and single‐crystal X‐ray diffraction analyses. Capulchemins A–F possess a rare aromatic C ring, while capulchemin K with a 15,16‐degradative carbon skeleton represents a rare group of cassane diterpenes. Capulchemin A exhibited remarkable antibacterial activity against four phytopathogenic bacteria, particularly against Pseudomonas syringae pv. actinidae and Bacillus cereus, with minimal inhibitory concentration values of 3.13 μM. Meanwhile, capulchemin A showed significant control effect on kiwifruit canker in vivo. Further investigation of its mechanism of antibacterial activity revealed that compound 1 was closely related to destroy cell membrane to cause cell death. Additionally, some of those cassane diterpenoids showed potential antifeedant against Mythimna separate walker and Plutella xylostella. Consequently, capulchemin A could have the potential to be used as a template for the development for new eco‐friendly NP‐based bactericides. CONCLUSION: These data contribute to a better understanding of the antibacterial activity of cassane diterpenes. Cassane diterpenes have been discovered to be leading to broad application prospects in the development as novel botanical bactericides. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Silver (Ag) complexes of drugs and their nanosystems have great potential as antibacterials. Recently, an Ag complex of furosemide (Ag–FSE) has shown to be a promising antimicrobial. However, poor solubility of Ag–FSE could hamper its introduction into clinics. Therefore, the authors developed a nanosuspension of Ag–FSE (Ag–FSE_NS) for its solubility and antibacterial activity enhancement. The aim of this study was to introduce a novel nanoantibiotic with enhanced antibacterial efficacy. Ag–FSE_NS was prepared by precipitation–ultrasonication technique. Size, polydispersity index (PI) and zeta potential (ZP) of prepared Ag–FSE_NS were measured by dynamic light scattering, whereas surface morphology was determined using scanning electron microscopy (SEM). In vitro antibacterial activity was evaluated against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa using broth microdilution method. Size, PI and ZP of optimised Ag–FSE_NS1 were 191.2 ± 19.34 nm, 0.465 ± 0.059 and −55.7 ± 8.18 mV, respectively. SEM revealed that Ag–FSE_NS1 particles were rod or needle‐like with smooth surfaces. Saturation solubility of Ag–FSE in NS increased eight‐fold than pure Ag–FSE. Ag–FSE_NS1 exhibited two‐fold and eight‐fold enhancements in activity against E. coli and S. aureus, respectively. The results obtained showed that developed Ag–FSE_NS1 holds a promise as a topical antibacterial. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) have been undeniable for its antimicrobial activity while its antitumour potential is still limited. Therefore, the present study focused on determining cytotoxic effects of AgNPs on Michigan cancer foundation‐7 (MCF‐7) breast cancer cells and its corresponding mechanism of cell death. Herein, the authors developed a bio‐reduction method for AgNPs synthesis using actinomycetes isolated from marine soil sample. The isolated strain was identified by 16s ribotyping method and it was found to be Streptomyces atrovirens. Furthermore, the synthesised AgNPs were characterised by various bio‐analytical techniques such as ultraviolet–visible spectrophotometer, atomic force microscopy, transmission electron microscopy, Fourier transform infra‐red spectroscopy, and X‐ray diffraction. Moreover, the results of 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide assay reveals 44.51 µg of AgNPs to have profound inhibition of cancer cell growth; furthermore, the inhibition of MCF‐7 breast cancer cell line was found to be dose dependent on treatment with AgNPs. Acridine orange and ethidium bromide double staining methods were performed for cell morphological analysis. The present results showed that biosynthesised AgNPs might be emerging alternative biomaterials for human breast cancer therapy. [ABSTRACT FROM AUTHOR]

Diimidazolium-based organic salts, bearing peptides or amino acids as anions have been synthesised and tested for their gelling ability in biocompatible solvents. These low molecular weight salts were successfully used as gelators in phosphate buffered saline (PBS) solution and ionic liquids. Then, the properties of the obtained soft materials were analysed in terms of melting temperature and gel strength as accounted for by rheological investigations. The gel-phase formation was studied by using UV/Vis and resonance light scattering measurements, whereas the morphology of the soft materials was analysed by using polarised optical microscopy and scanning electron microscopy. To get information about the organisation of the gelator in the gelatinous matrix, X-ray diffraction measurements were performed both on the neat gelators and their gels. The results collected show that the properties of the gel phases, like the thermal stability, the self-repairing ability, the resistance to flow as well as the morphology, are dependent on the nature of the anion. Furthermore, bioassays revealed that the obtained diimidazolium organic salts possessed antimicrobial activity, against gram-negative and gram-positive tester strains. In particular and noteworthy, the diimidazolium organic salts exert a bactericidal capability, which was retained even if they are included in the gel phase. Thus, a novel kind of bioactive soft material was obtained that could be fruitfully employed as a non-covalent coating exerting antibacterial capability. [ABSTRACT FROM AUTHOR]

In the present study, silver nanoparticles (AgNPs) were synthesised by adding 1 mM Ag nitrate solution to different concentrations (1%, 2.5%, 5%) of branch extracts of Eurycoma longifolia, a well known medicinal plant in South–East Asian countries. Characterisation of AgNPs was carried out using techniques such as ultraviolet–visible spectrophotometry, X‐ray diffractrometry, Fourier transform infrared–attenuated total reflection spectroscopy (FTIR–ATR), scanning electron microscopy. XRD analysis revealed face centre cubic structure of AgNPs and FTIR–ATR showed that primary and secondary amide groups in combination with the protein molecules present in the branch extract were responsible for the reduction and stabilisation of AgNPs. Furthermore, antioxidant [2,2‐diphenyl‐1‐picrylhydrazyl and 2,2′‐Azino‐bis(3‐ethylbenzthiazoline‐6‐sulphonic acid)], antimicrobial and anticancer activities of AgNPs were investigated. The highest bactericidal activity of these biogenic AgNPs was found against Escherichia coli with zone inhibition of 11 mm. AgNPs exhibited significant anticancer activity against human glioma cells (DBTRG and U87) and human breast adenocarcinoma cells (MCF‐7 and MDA‐MB‐231) with IC50 values of 33, 42, 60 and 38 µg/ml. [ABSTRACT FROM AUTHOR]

Summary: In this study, the copper nanoparticles were synthesized using various concentrations (5%, 6 %, 8%, and 10%) of Nigella sativa seed extracts, and their antibacterial and antiobesity effect was evaluated. The optimum particle size (98.23 nm) of nanoparticles was obtained at an extract concentration of 8%. FTIR results confirmed the functional groups responsible for copper ion reduction, The synthesized nanoparticles exhibited high antibacterial activity against Pseudomonas aeruginosa and Escherichia coli having inhibition zone of 25 mm and 24 mm, respectively. Significantly (P < 0.005) percent lipase and amylase inhibition assay of copper nanoparticles confirmed their antiobesity activities. [ABSTRACT FROM AUTHOR]