Strong Antibacterial Effect Research Articles

Antibacterial Activity, Probiotic Potential, and Biocontrol Efficacy of Two Lactic Acid Bacteria Against Penicillium expansum on Fresh Grapes

Lactic acid bacteria are commonly present in various sources and possess significant probiotic properties. They can inhibit pathogenic bacteria and fungi simultaneously, making them promising candidates as bio-preservatives. This study investigated two potential probiotic strains: Lactiplantibacillus plantarum LR5-2 (isolated from fermented meat products) and Lacticaseibacillus rhamnosus SQ63 (isolated from infant feces). The study evaluated their aggregation ability, anti-pathogenic activity, safety, and tolerance to gastrointestinal conditions, phenol, and bile salts. Additionally, their biological control potential against Penicillium expansum on fresh grapes was assessed. The results demonstrated that both strains exhibited high survival rates under extreme gastrointestinal conditions, enhanced Auto-aggregation, co-aggregation, and hydrophobicity. They displayed strong antioxidant activity and significant antibacterial effects against 11 pathogenic fungi and foodborne pathogens. Biosafety testing revealed that both strains are sensitive to most antibiotics, do not produce biogenic amines, and exhibit no hemolytic or DNase activity. In grapes, L. plantarum LR5-2 and L. rhamnosus SQ63 significantly reduced the incidence and disease index of P. expansum infection. In conclusion, the characterization analysis and bio-preservation experiments revealed that LR5-2 and SQ63 have strong potential as probiotics and bio-preservatives.

Experimental and computational studies of Schiff bases derived from 4-aminoantipyrine as potential antibacterial and anticancer agents

Schiff bases are organic compounds recognized for their biological activities, including antiviral, antibacterial, antifungal, and anticancer properties, making them promising candidates in medicinal chemistry. In this studio, a series of Schiff bases 3a–h derived from 4-aminoantipyrine and substituted cinnamaldehydes were evaluated in vitro against liver (HepG2) and thyroid (THJ29T) cancer cells, Gram-positive and Gram-negative multidrug-resistant bacteria, and biofilm-forming pathogens. Six compounds demonstrated anticancer activity, though some exhibited toxicity to non-tumor cells. Compounds 3b, 3f, and 3h showed notable anticancer potential, while 3f and 3h also exhibited strong antibacterial effects, with 3f being the most effective against multidrug-resistant bacteria strains. These Schiff bases also inhibit biofilm formation, suggesting their potential for treating biofilm-related infections. In-silico analyses of their ADME properties, global reactivity descriptors, and binding affinities corroborated these findings. The Schiff base 3f has a strong binding affinity for DNA gyrase and vitamin D receptor, suggesting potential mechanisms for its antibacterial and anticancer activities.

Phytochemical, antioxidant, and antimicrobial properties of Bellardia trixago methanol and ethanol extracts: insights from ADMET and molecular docking approaches

Abstract This study investigates the antioxidant, antimicrobial, and phytochemical properties of ethanol and methanol extracts derived from Bellardia trixago flowers alongside molecular docking and pharmacokinetic assessments of stigmasterol, a key bioactive compound. The antioxidant activities of the ethanol and methanol extracts were determined, with the methanol extract demonstrating higher activity, 0.370 ± 0.002 mg/mL, compared to the ethanol extract, 0.95 ± 0.09 mg/mL. The total phenolic content of the ethanol extract was 79.14 ± 2.30 mg GAE/g extract DW, and its flavonoid content was 244.31 ± 12.51 mg QE/g extract DW. The methanol extract contained a lower phenolic content of 51.50 ± 1.43 mg GAE/g extract DW but a higher flavonoid content of 251.67 ± 6.68 mg QE/g extract DW. The ethanol extract exhibited a superior iron chelation capacity of 8.21 ± 0.09 mg/mL relative to the methanol extract of 6.68 ± 0.28 mg/mL. Antimicrobial assays demonstrated that both extracts exhibited strong bactericidal and bacteriostatic effects, with MIC values ranging from < 0.39 mg/mL to > 125 mg/mL. The highest antimicrobial activity was observed against Bacillus cereus NRRL B-3711. Phytochemical analysis identified 25 compounds in the methanol extract and 20 in the ethanol extract. Stigmasterol was the major constituent in both extracts, accounting for 26.51% in ethanol and 12.65% in methanol. Molecular docking studies of stigmasterol revealed strong binding affinities with several protein targets, including Candida albicans Complex III2 (-8.7 kcal/mol), Escherichia coli HipBST (-7.2 kcal/mol), and the ribosomal subunit of Staphylococcus aureus (-7.0 kcal/mol). These interactions highlight stigmasterol’s potential role in modulating bacterial and fungal protein functions, emphasising the potential therapeutic applications of B. trixago, particularly in antimicrobial and antioxidant contexts.

Modulation of the mechanism of action of antibacterial silver N-heterocyclic carbene complexes by variation of the halide ligand.

The antimicrobial properties of silver and silver complexes have been known in medicine since ancient times. However, limitations in stability and solubility have impaired medicinal chemistry and drug development research. With the advent of N-heterocyclic carbenes (NHC) as ligands, the development of synthesis methods for organometallic silver species of the type (NHC)AgX (where X = halide) has brought significant improvements, and the class of antimicrobial silver NHC complexes has emerged. However, reports studying structure-activity relationships and the mechanism of action of this compound type are still rare. This paper explores the activity of silver NHC complexes with halide (chloride, iodide) ligands and attempts to elucidate their mechanism of antibacterial action in Gram-negative E. coli bacteria in comparison to non-organometallic silver nitrate. In particular, the complexes with an iodide ligand were confirmed to cause stronger antibacterial effects in E. coli than silver nitrate. Moreover, iodide complexes exhibit an enhanced cellular uptake, show signs of DNA condensation, strongly inhibit TrxR in E. coli and cause a strong depolarization of the membrane potential and permeability of the inner cell membrane. In contrast, chloride silver NHC complexes and silver nitrate caused permeability of the outer membranes and also showed a different activity pattern in most of the studied mechanisms. In conclusion, by variation of the halide ligand of silver NHC complexes the mechanism of action and strength of antibacterial activity can be fine-tuned.

Microstructure, wear, and corrosion properties of PEEK-based composite coating incorporating titania- and copper-doped mesoporous bioactive glass nanoparticles.

Poor wear- and corrosion-resistance of 316L SS implants are critical problems in orthopedic implants. This study aims to improve the wear- and corrosion-resistance of 316L SS through surface coating. In this study, a bilayer composite coating consisting of polyether ether ketone (PEEK) as the first layer, and titania (TiO2)- and Cu-doped mesoporous bioactive glass nanoparticles (Cu-MBGNs) were deposited as the second layer on a 316L SS via electrophoretic deposition (EPD). Scanning electron microscopy (SEM) images of the bilayer composite coating showed the distribution of TiO2 and Cu-MBGNs within the PEEK matrix. Energy dispersive spectroscopy (EDS) analysis confirmed the presence of TiO2 and Cu-MBGNs in the bilayer composite coating. Fourier transform infrared spectroscopy (FTIR) identified the functional groups attributed to the PEEK, TiO2 and Cu-MBGNs. X-ray diffraction (XRD) analysis confirmed the presence of TiO2 (anatase) and Cu-MBGNs in the bilayer composite coating. The coating exhibited a strong antibacterial effect against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Incorporating TiO2/Cu-MBGNs into the bilayer composite coating significantly modified the surface of 316L SS by improving the wear- and corrosion-resistance. Pin on disc test revealed that the specific wear rate of ∼(0.4570 ± 0.009) × 10-6 mm3 Nm-1 of the PEEK coating decreased to (0.0482 ± 0.007) × 10-6 mm3 Nm-1 on incorporating TiO2/Cu-MBGNs in PEEK coating under a normal load of 10 N in Dulbecco's Modified Eagle Medium (DMEM). Furthermore, electrochemical impedance spectroscopy (EIS) results revealed that the impedance value of the bilayer composite coating remained ∼4.56 × 105 Ω cm2 compared to 8.81 × 103 Ω cm2 of 316L SS after 24 h immersion in phosphate-buffered saline (PBS). Thus, this study demonstrated that the wear- and corrosion-resistance of 316L SS can be improved by incorporating TiO2/Cu-MBGNs in PEEK-based composite coatings for orthopedic applications.

Eco-Friendly Synthesis of Zirconium Dioxide Nanoparticles from Toddalia asiatica: Applications in Dye Degradation, Antioxidant and Antibacterial Activity.

Zirconium dioxide nanoparticles (ZrO2 NPs) have gained significant attention due to their excellent bioavailability, low toxicity, and diverse applications in the medical and industrial fields. In this study, ZrO2 NPs were synthesized using zirconyl oxychloride and the aqueous leaf extract of Toddalia asiatica as a stabilizing agent. Analytical techniques, including various spectroscopy methods and electron microscopy, confirmed the formation of aggregated spherical ZrO2 NPs, ranging from 15 to 30 nm in size, with mixed-phase structure composed of tetragonal and monoclinic structures. UV-visible spectroscopy showed a characteristic band at 281 nm with a bandgap energy of 3.7 eV, indicating effective stabilization by the phytochemicals in T. asiatica. EDX analysis revealed that the NPs contained 37.18 mol.% zirconium (Zr) and 62.82 mol.% oxygen. The ZrO2 NPs demonstrated remarkable photocatalytic activity, degrading over 95% of methylene blue dye after 3 h of sunlight exposure. Additionally, the ZrO2 NPs exhibited strong antibacterial effects, particularly against Gram-negative bacteria such as E. coli, and significant antioxidant activity, with low IC50 values for hydroxyl radical scavenging. In conclusion, the green synthesis of ZrO2 NPs using T. asiatica leaf extract is an effective, eco-friendly method that produces nanoparticles with remarkable antioxidant, antimicrobial, and photocatalytic properties, highlighting their potential for applications in water treatment, environmental remediation, and biomedicine.

In vitro Antioxidant and Antibacterial Activities, Bioactive Compounds, Organic Acids, Sugars, Micro- and Macro-elements of Aquilaria agallocha Root Organic Extracts

Aquilaria agallocha is an economically valuable plant facing endangerment, sought after globally for its production of agarwood. A. agallocha tree possesses medicinal and aromatic properties in its fruits, branches, leaves, wood, and roots, which are being studied for their effective compounds and their potential bioactive effects on human health. This study aimed to uncover the phytochemical properties and biological activities of A. agallocha roots, which possess medicinal and aromatic characteristics. The phenolic, organic acid, and sugar profiles of A. agallocha roots were determined using HPLC-DAD, while mineral distributions were analyzed via ICP-AES. In vitro antioxidant capacity was assessed using the 2,2-diphenyl- 1-picrylhydrazyl (DPPH) assay. Furthermore, the antibacterial effects of methanol extracts of A. agalocha roots against S. aureus, S. carnosus, B. cereus, L. monocytogenes, E. coli, L. innocua, K. pneumoniae, and E. faecalis were estimated with disc diffusion and MIC methods. The amount of total phenolic and in vitro DPPH radical scavenging capacity of A. agalocha roots were determined as 7.529 mg GAE/g and 18.83 µmol TE/g, respectively. Eight phenolic components were detected in the extracts of A. agalocha roots. The most dominant among these phenolic compounds detected was tannic acid, which was followed by 4-hydrobenzoic acid and oleuropein, respectively. In the aqueous extracts of A. agalocha roots, four organic acids were identified, including citric, tartaric, malic and succinic acid, and succinic acid was the most dominant organic acid. Only fructose sugar was detected in the water extracts of A. agalocha roots. The extracts of A. agalocha roots had a strong antibacterial effect against all gram-positive pathogens except for S. carnosus, but did not have any effect against gram-negative bacteria.

Synergistic Antibacterial Effect of ZnO Nanoparticles and Antibiotics against Multidrug-resistant Biofilm Bacteria.

The misuse of antibiotics leads to a global increase in antibiotic resistance. Therefore, it is imperative to search for alternative compounds to conventional antibiotics. ZnO nanoparticles (Zn NP) are one of these alternatives because they are an effective option to overcome biofilm bacterial cells and a novel way to overcome multidrug resistance in bacteria. The current research study aims to characterize the efficacy of ZnO nanoparticles alone and in combination with other antibacterial drugs against bacterial biofilms. ZnO NPs were prepared by co-precipitation method, and their anti-biofilm and antibacterial activities alone or combined with four types of broad-spectrum antibacterial (Norfloxacin, Colistin, Doxycycline, and Ampicillin) were evaluated against E. coli and S. aureus bacterial strains. Finally, the cytotoxicity and the hemolytic activity were evaluated. ZnO NPs were prepared, and results showed that their size was around 10 nm with a spherical shape and a zeta potential of -21.9. In addition, ZnO NPs were found to have a strong antibacterial effect against Gram-positive and Gram-negative microorganisms, with a minimum inhibitory concentration (MIC) of 62.5 and 125 μg/mL, respectively. Additionally, they could eradicate biofilmforming microorganisms at a concentration of 125 μg/m. ZnO NPs were found to be non-toxic to erythrocyte cells. Still, some toxicity was observed for Vero cells at effective concentration ranges needed to inhibit bacterial growth and eradicate biofilm-forming organisms. When combined with different antibacterial, ZnO NP demonstrated synergistic and additive effects with colistin, and the MIC and MBEC of the combination decreased significantly to 0.976 μg/mL against planktonic and biofilm strains of MDR Gram-positive bacteria, resulting in significantly reduced toxicity. The findings of this study encourage the development of alternative therapies with high efficacy and low toxicity. ZnO nanoparticles have demonstrated promising results in overcoming multi-drug resistant bacteria and biofilms, and their combination with colistin has shown a significant reduction in toxicity. Further studies are needed to investigate the potential of ZnO nanoparticles as a viable alternative to conventional antibiotics.

Step-scheme/Mott-Schottky integrated heteroiunctions in BiFeO3/ZnIn2S4/Ag hollow nanospheres: Facilitating efficient piezo-photocatalytic activation of peroxydisulfate to enhance nizatidine degradation and antibacterial activity.

The piezo-photocatalysis enhanced by piezoelectric nanogenerators is considered one of the most effective methods for treating emerging contaminants (ECs) in environmental water. In this study, BiFeO3/ZnIn2S4/Ag (BFO/ZIS/Ag) with boosting piezo-photocatalytic performance was synthesized by modulating the interaction between the step-scheme (S-scheme) heterojunction and the Mott-Schottky barrier. The catalytic rate of the optimized BFO/ZIS/Ag-0.01 catalyst is 4.85×10-2 min-1 for the degradation of niazitidine (NZT) under both ultrasonic and visible light radiation, which is respectively 4.3 and 4.8 times higher than that of pure BFO and ZIS. Furthermore, the total organic carbon (TOC) test revealed that NZT degradation reached 98.4% after 120min of continuous reaction. This enhanced piezo-photocatalytic performance is mainly due to the synergistic effect of integrated heterojunction and piezoelectric field. DFT calculations revealed that the charge transfer enhancement at the heterogeneous interface resulted from directional electron transfer to ZIS via Zn-O and S-Ag channels, following the introduction of Ag nanoparticles, which shortened the carrier separation path. Additionally, BFO bent the band of the composite catalyst, promoting carrier separation. These resulted in the generation of abundant highly active 1O2, which specifically targeted and disrupted stable NZT molecules. Moreover, BFO/ZIS/Ag-0.01 exhibited strong inhibitory and antibacterial effects against Escherichia coli and Staphylococcus aureus via electrostatic adsorption and ionization. This study offers new insights into the restoration of aquatic environments and bacterial disinfection through the use of piezoelectric catalytic materials.

Characterization and Evaluation of Zero-Order Release System Comprising Glycero-(9,10-trioxolane)-trialeate and PLA: Opportunity for Packaging and Biomedicine Applications.

Glycerol-(9,10-trioxolane) trioleate (OTOA) is a promising material that combines good plasticizing properties for PLA with profound antimicrobial activity, which makes it suitable for application in state-of-the-art biomedical and packaging materials with added functionality. On the other hand, application of OTOA in PLA-based antibacterial materials is hindered by a lack of knowledge on kinetics of the OTOA release. In this work, the release of glycero-(9,10-trioxolane) trioleate (OTOA) from PLA films with 50% OTOA content was studied during incubation in normal saline solution, and for the first time, the kinetics of OTOA release from PLA film was evaluated. Morphological, thermal, structural and mechanical properties of the PLA + 50% OTOA films were studied during incubation in normal saline and corresponding OTOA release using differential scanning calorimetry (DSC), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy and mechanical tests. It was confirmed by DSC and XRD that incubation in the saline solution and corresponding OTOA release from PLA film does not lead to significant changes in the structure of the polymer matrix. Thus, the formation of more disturbed α' crystalline phase of PLA due to partial hydrolysis of amorphous zones and/or most unstable crystallites in the PLA/OTOA semi-crystalline structure was observed. The degree of crystallinity of PLA + OTOA film was also slightly increased at the prolonged stages of OTOA release. PLA + 50% OTOA film retained its strength properties after incubation in normal saline, with a slight increase in the elastic modulus and tensile strength, accompanied by a significant decrease in relative elongation at break. The obtained results showed that PLA + 50% OTOA film could be characterized by sustained OTOA release with the amount of released OTOA exceeding 50% of the initial content in the PLA film. The OTOA release profile was close to zero-order kinetics, which is beneficial in order to provide stable drug release pattern. Developed PLA + 50% OTOA films showed a strong and stable antibacterial effect against Raoultella terrigena and Escherichia coli, bacterial strains with multidrug resistance behavior. The resulting PLA + OTOA films could be used in a variety of biomedical and packaging applications, including wound dressings and antibacterial food packaging.

Phytochemical composition, antioxidant and antibacterial activity of the Philippine copperleaf (Acalypha wilkesiana) ethanolic extract

The Philippine copper leaf (Acalypha wilkesiana) is a relatively untapped plant with notable ethnopharmacological properties. This study investigated the phytochemical composition, antioxidant and antimicrobial activity of the leaf ethanolic extract of A. wilkesiana collected at Central Philippine University Gardens in Iloilo City, Philippines. Qualitative phytochemical analysis revealed the presence of bioactive compounds, including alkaloids, tannins, saponins, proteins, phenols, flavonoids, glycosides, carbohydrates, and terpenoids. Quantitatively, the total phenolics and flavonoid contents of the extract were 1,203.7±0.33 mg gallic acid equivalent (GAE)/g and 235.36±2.0 mg of quercetin equivalent (QE)/g, respectively. The antioxidant activity, assessed using the 1,1-diphenyl-1-picrylhydrazyl (DPPH) assay, demonstrated a concentration-dependent radical scavenging capacity. The ethanolic extract exhibited strong antibacterial effects against Staphylococcus aureus, methicillin-resistant S. aureus (MRSA), Streptococcus agalactiae, Escherichia coli, Edwardsiella tarda, Pseudomonas aeruginosa, and Salmonella typhi, with significant inhibition observed at 100 mg/mL. Resolute results from this first study on the phytochemicals, antioxidants, and antimicrobial activity of the Philippine copperleaf clearly demonstrate that it contains potent bioactive compounds with notable antibacterial and antioxidant properties. This underscores its potential for developing new therapeutic agents.

Ternary Thermosensitive Hydrogel‐Encapsulated Macrolactam Heneicosapeptide Eliminates Epidermal Multidrug‐Resistant Bi‐Microbial Colonization

AbstractSuperbug epidemic has rendered antibiotic therapeutics increasingly ineffective. Worse still, there are few applicable medication regimens for polymicrobial infections caused by two or more multidrug‐resistant bacteria. Herein, a panel of antibacterial cyclic peptides are designed and synthesized and the lead compound cyclo‐zp80r shows favorable activities against a broad spectrum of bacteria. Encouragingly, it exhibited a strong bactericidal effect against two important epidermic species Pseudomonas aeruginosa and Staphylococcus aureus for both single‐ and co‐infections. The peptide cyclo‐zp80r is proposed to destroy the membrane structures of both Gram‐negative and Gram‐positive bacteria, inducing a variety of physiological disorders. To better adapt to topical administration of this novel antibacterial agent, a hydrogel formulation consisting of poloxamer 407, poloxamer 188, and hyaluronic acid is optimized. This ternary hydrogel system is able to form in situ gel at skin temperature. Encapsulated peptide molecules are released steadily in both human skin ex vivo model and mouse wound in vivo model to treat bi‐microbial infection. This work systematically investigates the design, synthesis, antibacterial mechanism of a novel cyclic peptide, and its drug delivery strategy for topical wound infection, offering a promising therapeutics to treat multidrug‐resistant polymicrobial wound infections.

Synthesis and characterization of multi-responsive iron oxide nanoparticles: Evaluation of antibacterial properties and photocatalytic activity

Cape gooseberry (CG) plant leaf extract-mediated iron oxide nanoparticles (CG-IO NPs) were fabricated for antibacterial research. The ideal concentration of the precursor salt, pH (11) of the reaction mixture, reducing agent to precursor salt ratio, and the production time of iron oxide nanoparticles were 5 mM, 9.0, 3:7, and 25 min, respectively. The iron oxide nanoparticles were tested using ultraviolet–visible absorption spectroscopy, photoluminescence (PL) spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), thermogravimetric/differential thermal analysis (TG/DTA), and Fourier transform infrared (FTIR) spectroscopy. FTIR spectroscopy was used to identify functional groups of the compounds, including the carbonyl, CH, and OH bands that reduced and produced nanoparticles. The size and shape of the synthesized CG-IO NPs were determined by TEM and dynamic light scattering, with the median and mean size of 13.9 nm and 15.8 nm, respectively. The thermal stability of the synthesized CG-IO NPs was assessed using TG/DTA in a nitrogen atmosphere. The elements and oxidation states of the CG-IO NP components were examined by XPS. The luminosity of the CG-IO NP was examined using PL spectroscopy. The synthetic CG-IO NPs exhibited strong antibacterial effects against dangerous bacteria, such as Salmonella enterica (S. entirica), Escherichia coli (E. coli), Streptococcus agalactiae, and Staphylococcus aureus. CG-IO NPs assisted in water reclamation by decomposing Malachite Green dye under solar light irradiation.

Antibacterial activity of zinc oxide nanoparticles against Shewanella putrefaciens and its application in preservation of large yellow croaker (Pseudosciaena crocea).

Specific spoilage organisms (SSOs) are the key factors affecting the deterioration of large yellow croaker. This study investigated the antibacterial activity and mechanism of Zinc oxide nanoparticles (ZnO-NPs) against Shewanella putrefaciens. The effects of different concentrations of ZnO-NPs (0.5, 1, 2mg/mL) combined with seawater slurry ice preservation on storage quality and microbial community of large yellow croaker were further investigated. The results showed that ZnO-NPs had a strong antibacterial effect on Shewanella putrefaciens, which destroyed the integrity of the cell membrane, resulting in nucleic acid leakage and increased electrical conductivity. In addition, ZnO-NPs could effectively inhibit the proliferation of microorganisms, slow down the rate of lipid oxidation, delay the rise of pH value and total volatile basic nitrogen, and maintain the color of fish. Among them, 2mg/mL ZnO-NPs treatment showed the best preservation effect on large yellow croaker. High-throughput sequencing results showed that Pseudoalteromonas and Shewanella became the dominant spoilage bacteria with the extension of storage time. ZnO-NPs significantly reduced the relative abundance of dominant spoilage bacteria and changed the microbial composition of fish. Inhibition of the growth of SSOs was important for delaying spoilage and prolonging the shelf-life of large yellow croaker. Therefore, ZnO-NPs combined with seawater slurry ice preservation could be used as a new storage method, which provides a new idea for food quality and safety control.

Antimicrobial Activity of Thyme, Olive Oil, and Their Nanoemulsions Against Cronobacter Sakazakii: In Vivo Application as Natural Food Preservatives in Tallaga Cheese

ABSTRACTTallaga cheese is the most popular type of white soft cheese in Egypt. Cronobacter sakazakii is an opportunistic foodborne pathogen that poses a threat to the health of almost every age group, with a particular emphasis on neonates and infants. Essential oils (EOs), such as olive oil and thyme oil, exhibit a broad‐spectrum antibacterial effect. However, few studies have investigated the antibacterial activity of these EOs and their formulated nanoemulsions (NEs)—olive oil nano‐emulsions (ONE) and thyme oil nano‐emulsions (TNE)—on C. sakazakii in cheese to date. The purpose of this study was to investigate the inhibitory effects of these EOs and their NEs on the development of C. sakazakii during the processing and storage of Tallaga cheese. Additionally, the organoleptic properties of the resulting cheese were evaluated. Herein, ONE and TNE were prepared and characterized using a zetasizer and transmission electron microscopy (TEM). Furthermore, the minimum inhibitory concentrations (MICs) of EOs and NEs were determined using well diffusion assay. Fresh buffalo's milk for the elaboration of Tallaga cheese was inoculated with C. sakazakii at a concentration of 6 log CFU/mL, along with the addition of MICs of either EOs or NEs. The obtained results showed that the MICs were 15 mg/mL (v/v) for either olive oil, thyme oil, ONE and TNE with diameter inhibition zones of 10.3 ± 0.5, 13.3 ± 1.7, 12.3 ± 0.5, and 16 ± 0.8 mm, respectively. In addition, NEs exhibited high antibacterial activities against C. sakazakii in comparison to pure EOs. Particularly, the strongest antibacterial effect toward C. sakazakii was reported with TNE during manufacturing and storage of Tallaga cheese. Overall, these results suggest that thyme and its NEs have the potential to prevent bacterial contamination by C. sakazakii in the dairy industry.

Green Synthesis of Silver Nanoparticles (CM-AgNPs) from the Root of Chuanminshen for Improving the Cytotoxicity Effect in Cancer Cells with Antibacterial and Antioxidant Activities.

The unique properties of silver nanoparticles (AgNPs), such as size, surface charge, and the ability to release silver ions, contribute to DNA damage, inducing of oxidative stress, and apoptosis in cancer cells. Thus, the potential application of AgNPs in the field of biomedicine, and cancer therapy are rapidly increasing day by day. Therefore, in this study, AgNPs were synthesized by extract of Chuanminshen violaceum, and then the synthesized CM-AgNPs were fully characterized. The biological activity of CM-AgNPs was investigated for antibacterial, antioxidant, and anticancer activities. The cytotoxic activity of CM-AgNPs was tested for various kinds of cancer cells including MKN45 gastric cancer cells, HCT116 human colon cancer cells, A549 human lung cancer cells, and HepG2 liver cancer cells. Among these cancer cells, the induced apoptosis activity of CM-AgNPs on HCT116 cancer cells was better and was used for further investigation. Besides, the CM-AgNPs exhibited great antioxidant activity against 1,1-diphenyl-2-picrylhydrazyl (DPPH) with 50% free radical scavenging activity, and CM-AgNPs also showed a significant antibacterial activity against Escherichia coli and Staphylococcus aureus. Thus, our pilot data demonstrated that the green synthesis of CM-AgNPs would be considered a good candidate for the treatment of HCT116 cancer cells, with its strong antioxidant activity and antibacterial effects.

Assessment of nutritional composition, phytochemical screening, antioxidant, and antibacterial activities of date palm (Phoenix dactylifera) seeds

Phoenix dactylifera seeds possess numerous health benefits, such as antioxidant, anti-inflammatory, and antimicrobial activities, due to presence of unique phytochemical components. In present study, the nutritional composition, phytochemical screening, anti-oxidant, and antimicrobial activity of date palm seed were investigated. Results of the present investigation revealed that date seed extract contains moisture content (4.34%), ash content (1.2%), protein (4.4%), and crude fiber (15.87/100 g) on a dry basis. This study explored the valorization potential of date seed by indicating the presence of beneficial phytochemicals such as alkaloids, phenols, flavonoids, terpenoids, and tannins, except steroids and cardiac glycosides. The total phenolic content was found to be 448 mg gallic acid equivalent (GAE) per 100 g of date seed powder, while the antioxidant activity (%) was determined to be 87.04 ± 1.98. FTIR spectral studies revealed the presence of different functional groups such as OH, C–H, C=O, and CH2 within the range of 3800–800 cm−1. Furthermore, gallic acid concentration in the date seed extract was noted to be 13.293 μg/mL using HPLC analysis. A strong antibacterial effect was observed against Pseudomonas aeruginosa and Bacillus cereus, resulting in the inhibition zone diameters of 18 mm and 17 mm, respectively. However, the antibacterial activity was found to be less effective against Escherichia coli and Staphylococcus aureus, both with an inhibition zone diameter of 16 mm. The research findings suggest that date seeds offer diverse medical applications and may serve as a potential source for various bioactive components.

Magnesium-Doped Hydroxyapatite Nanofibers for Medicine Applications: Characterization, Antimicrobial Activity, and Cytotoxicity Study.

Magnesium-doped hydroxyapatite (HAp-Mg) nanofibers show promise for medical applications due to their structural similarity to bone minerals and enhanced biological properties, such as improved biocompatibility and antimicrobial activity. This study synthesized HAp-Mg nanofibers using a microwave-assisted hydrothermal method (MAHM) to evaluate their cytotoxicity, biocompatibility, and antimicrobial efficacy compared to commercial hydroxyapatite (HAp). Characterization through X-ray diffraction (XRD), scanning electron microscopy (SEM), Transmission Electron Microscopy (TEM), energy-dispersive X-ray spectroscopy (EDS), and Fourier transform infrared spectroscopy (FTIR) confirmed the successful incorporation of magnesium, producing high-purity, crystalline nanofibers with hexagonal morphology. Rietveld refinement showed slight lattice parameter shortening, indicating Mg2+ ion integration. Cell viability assays (MTT and AlamarBlue) revealed a significant increase in fibroblast proliferation with 2% and 5% HAp-Mg concentrations compared to controls (p < 0.05), demonstrating non-cytotoxicity and enhanced biocompatibility. Antimicrobial tests (disk diffusion method, 100 µg/mL) showed that HAp-Mg had strong antibacterial effects against Gram-positive and Gram-negative bacteria and moderate antifungal activity against Candida albicans. In contrast, commercial HAp showed no antimicrobial effects. These results suggest HAp-Mg nanofibers have significant advantages as biomaterials for medical applications, particularly in preventing implant-related infections and supporting further clinical development.

Isolation of Bacillus Velezensis from Leepuram Sea Sediment and Its Bioactive Compound and Antimicrobial Activity

Research into marine bacteria in India for their potential active chemicals is essential for the creation of medications derived from marine sources. The objective of this research was to collect Bacillus velezensis from Leepuram Sea Sediment, test their antibacterial efficacy with the agar diffusion method, and find secondary metabolites by GC-MS spectroscopy.Traditional microbiological methods and phylogenetic analysis of 16S rRNA sequences were used to successfully identify Bacillus velezensis from sediment samples obtained in the Leepuram Sea, Kanyakumari. Using the agar well diffusion method, we tested the isolated metabolites for their antibacterial activity against Gram-positive and Gram-negative bacteria. The results showed that the extract had a strong antibacterial effect, inhibiting the growth of harmful bacteria with zones of inhibition as large as 19 mm for E. coli and Pseudomonas.Bacillus velezensis produces secondary metabolites with pharmacological potential, according to this study. These metabolites may have useful uses in biocontrol, agriculture, and medicine. The implications of these results for human health and the creation of new antimicrobial drugs are likely to grow substantially when more worldwide research is carried out.

Exploring local edible plants as potential prebiotic sources for their synbiotic applications

This study investigates the identification of local edible plants as sources of inulin and evaluates their potential to promote probiotic growth and inhibit pathogenic bacteria, with the goal of advancing synbiotic development. Prebiotics, defined as dietary fibers that are selectively fermented by probiotics to confer health benefits, have garnered increasing attention in recent research. This study aimed to identify local edible plants as sources of inulin and assess their potential for functional food applications. Histochemical microscopic analysis revealed the presence of inulin crystals in fifteen edible plants. Crude inulin extracts from Pachyrhizuserosus and Psidiumguajava L. showed notable prebiotic activity, promoting probiotic growth more effectively than standard inulin. Moreover, the cell-free supernatants of Lactobacillusplantarum ATCC14917, combined with the crude inulin extracts from P.erosus and P.guajava L., demonstrated significant bacteriostatic activity against Staphylococcusaureus ATCC25923. The synbiotic cultures exhibited strong bactericidal effects on S.aureus ATCC25923 and Escherichiacoli ATCC25922, achieving a >90% inhibition rate (3–5 log CFU/mL reduction) after incubation. Notably, specific combinations, such as L.plantarum ATCC14917 with P.guajava L. and Bifidobacteriumlongum MTC1007 with P.erosus, yielded the highest prebiotic activity scores. These findings suggest that Pachyrhizuserosus and Psidiumguajava L. are promising local sources of inulin, with the potential to support probiotic growth and contribute to the development of effective synbiotic formulations.