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Introduction: Nowadays, Cyanobacteria are one of the important candidates in the green biosynthesis of nanoparticles. Considering the detrimental effects of chemically synthesized nanoparticles, the aim of this study was the biosynthesis and antimicrobial activity of nanoparticles by aquatic cyanobacterium. Methods: Silver nanoparticles (AgNPs) were biosynthesized using three different approaches: wet biomass, boiling, and extracellular polysaccharides (EPS). Alginate coating was employed to enhance the nanoparticles' stability. Characterization of the nanoparticles was performed using UV-vis spectroscopy, Fourier transform infrared (FTIR) analysis, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and zeta potential measurements. The antimicrobial properties of the nanoparticles were evaluated against fish pathogenic bacteria and fungi. Statistical analyzes were performed with SPSS version 16 software, and the significant difference between the means was performed with one-way analysis of variance with 95% confidence limits and Tukey's test, and the results were drawn as a graph with Excel software. Results: The UV-vis spectroscopy results confirmed the synthesis of AgNPs in all three methods. FTIR analysis revealed similar spectra for all three methods, indicating comparable purity and production of similar compounds. Electron microscope images showed the sphericity of nanoparticles prepared by boiling method, and the average diameter of uncoated and alginate coated nanoparticles was 38 and 180.04 nm, respectively. Zeta potential analysis indicated a positive surface charge on the nanoparticles. The highest zone of inhibition was observed for AgNPs synthesized by the boiling method and coated with alginate. Similar results were obtained for the antifungal activity, with Saprolegnia exhibiting higher sensitivity to the synthesized nanoparticles compared to the other species studied. Conclusion: The novel strain Dulcicalothrix alborzica demonstrated potential as a potent producer of AgNPs with unique properties and promising applications in microbial biotechnology.

Abstract Water-soluble fluorescent N-doped carbon quantum dots (N-CQDs) were hydrothermally prepared through a green synthesis route using castor seeds as a single precursor and a hydrothermal method. Several experimental techniques have been used to characterize synthesized N-CQDs to confirm their structure and to verify their applicability in cell imaging and pH sensing. The synthesized N-CQDs were found to have are characterized by amorphous nature with a spherical shape with an average particle size of 6.57 nm as revealed from XRD and TEM measurements. The FTIR results reveal the presence of carboxylic and hydroxyl functional groups on the surface of the CQDs, which was also confirmed by XPS analysis. The fluorescence characterization of the synthesized N-CQDs showed blue emission and excitation dependence with good photostability. It was found that the optimal excitation and emission wavelengths were (λEx = 360) and (λEm = 432) nm, respectively. The fluorescence quantum yield (QY) of about 9.6% at the optimum excitation wavelength 360 nm. Moreover, the fluorescence intensity of N-CQDs showed good linear dependence with the pH values in ranges of 3.5 − 7.5 and 8 − 12 as well as high sensitivity for slight changes of pH values. According to these results, two fluorescent pH sensors were created based on acidic and basic media. The obtained N-CQDs have zeta potential of -21.86 mV and thus have excellent stability in water. Moreover, N-CQDs derived from the castor seeds have antimicrobial activity and exhibits low cytotoxicity to WI-13 cells with IC50 = 394.4 ± 13.8 µg/mL. The results of this study demonstrated that the synthesized N-CQDs derived from castor seeds can be used as pH sensing and antimicrobial materials. On the other hand, they are also promising in applications in cell imaging, thermo-sensing and optoelectronics.

Abstract This research investigates a novel nanocomposite material composed of reduced graphene oxide (rGO) and nickel-5,15-bisdodecylporphyrin (Ni-BDP) nanoparticles for the effective removal of methyl orange (MO), a harmful synthetic dye, from water. The structure and composition of the synthesized rGO/Ni-BDP nanocomposite were characterized using high-resolution transmission electron microscopy (HR-TEM), Raman spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, mass spectrometry, and ultraviolet-visible (UV-Vis) spectroscopy. The study demonstrates the material’s efficacy as both a catalyst and adsorbent for MO removal. Optimal performance was observed at pH 3.0, where the positively charged nanocomposite surface facilitated strong interactions with negatively charged MO molecules, leading to enhanced photocatalytic activity. Under these conditions, 0.01 g of the nanocomposite achieved an impressive 86.2% MO removal efficiency. Furthermore, the study explored the reusability of the rGO/Ni-BDP nanocomposite in repeated cycles of photocatalytic MO degradation under visible light irradiation. While exhibiting some decrease in efficiency over five cycles, the nanocomposite maintained a respectable degradation rate even after multiple uses. Finally, the antimicrobial properties of the nanocomposite were evaluated against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria exhibiting a zone of inhibition measuring 23 mm and 26, respectively. The minimum inhibitory concentration (MIC) values of 2.50 µg/ml and 1.25 µg/ml for Escherichia coli and Staphylococcus aureus, respectively. The results revealed significant antibacterial activity, demonstrating the broad-spectrum efficacy of the rGO/Ni-BDP nanocomposite. This research underscores the potential of the rGO/Ni-BDP nanocomposite as a versatile material for environmental remediation and antibacterial applications.

Metagenomics is an important technique for discovering and screening significant bioactive compounds such as polyketide synthases, non-ribosomal peptide synthetases, antibiotics, and biocatalysts. The enormous potential of microbial diversity in coastal lagoons remains untapped because of the difficulty of culturing many microorganisms under laboratory conditions. Therefore, this study aimed to decipher the structural and functional diversity of microbial communities, including un-culturable species in lagoon sediments collected from Tam Giang, Nai, and Thi Nai lagoons, which were located in the central coast of Vietnam using metagenomics approach. The results showed that all three large lagoons exhibited a high diversity of fungal species among the eukaryotic species and a high diversity of bacterial and archaeal species. Among them, the most prominent phyla included Ascomycota (fungal phyla), Firmicutes and Proteobacteria (bacterial phyla), and Thaumarchaeota (archaeal phyla). Sequencing of the metagenome samples of microbiome in the three lagoons of Tam Giang, Nai, and Thi Nai using shotgun sequencing technology revealed the existence of 126 potential gene sequences from the Tam Giang lagoon, 346 sequences from the Nai lagoon, and 341 sequences from the Thi Nai lagoon. These sequences participated in various metabolic processes and belonged to more than 30 groups of biologically active compounds. Most of these genes were related to antibacterial, antifungal, antiviral, cancer cell inhibition, and antioxidant activities. This is the first study conducted on lagoon microorganisms in Vietnam, opening up prospects and potential in exploiting microorganisms and biologically active substances with important applications in life from the lagoon ecosystems of Vietnam in particular and the overall world in general.

Abstract Background Although there are many uses for metal–organic framework (MOF) based nanocomposites, research shows that these materials have received a lot of interest in the field of water treatment, namely in the photodegradation of water contaminants, and disinfection of some pathogenic bacteria and fungi. This is brought on by excessive water pollution, a lack of available water, low-quality drinking water, and the emergence of persistent micro-pollutants in water bodies. Photocatalytic methods may be used to remove most water contaminants, and pathogenic microbes, and MOF is an excellent modifying and supporting material for photocatalytic degradation. Methods This work involved the fabrication of a unique Cu-MOF based nanocomposite that was exposed to gamma radiation. The nanocomposite was subsequently employed for photocatalytic degradation and as an antimicrobial agent against certain harmful bacteria and fungi. The produced Cu-MOf nanocomposite was identified by XRD, SEM, and EDX. Growth curve analysis, UV lighting impact, and antibiofilm potential have been carried out to check antimicrobial potential. Additionally, the membrane leakage test was used to determine the mechanism of the antimicrobial action. In an experimental investigation of photocatalytic activity, a 50 mL aqueous solution including 10.0 ppm of Rhodamine B (RB) was used to solubilize 10 mg of Cu-MOF. It has been investigated how pH and starting concentration affect RB elimination by Cu-MOF. Ultimately, RB elimination mechanism and kinetic investigations have been carried out. Results SEM images from the characterization techniques demonstrated the fact that the Cu-MOF was synthesized effectively and exhibited the Cu-MOF layers' flake-like form. Uneven clusters of rods make up each stratum. The primary peaks in the Cu-MOF's diffraction pattern were found at 2θ values of 8.75◦, 14.83◦, 17.75◦, 21.04◦, 22.17◦, 23.31◦, 25.41◦, and 26.38◦, according to the XRD data. After 135 min of UV irradiation, only 8% of RB had undergone photolytic destruction. On the other hand, the elimination resulting from adsorption during a 30-min period without light was around 16%. Conversely, after 135 min, Cu-MOF's photocatalytic breakdown of RB with UV light reached 81.3%. At pH 9.0, the greatest removal of RB at equilibrium was found, and when the amount of photocatalyst rose from 5 to 20 mg, the removal efficiency improved as well. The most sensitive organism to the synthesized Cu-MOF, according to antimicrobial data, was Candida albicans, with a documented MIC value of 62.5 µg mL−1 and antibacterial ZOI as 32.5 mm after 1000 ppm treatment. Cu-MOF also showed the same MIC (62.5 µg mL−1) values against Staphylococcus aureus and Escherichia coli, and 35.0 and 32.0 mm ZOI after 1000 ppm treatment, respectively. Ultimately, it was found that Cu-MOF (1000 µg/mL) after having undergone gamma irradiation (100.0 kGy) was more effective against S. aureus (42.5 mm ZOI) and E. coli (38.0 mm ZOI). Conclusion From the obtained results, the synthesized MOF nanocomposites had promising catalytic degradation of RB dye and high antimicrobial potential which encouraging their use in wastewater treatment against some pathogenic microbes and polluted dyes. Due to the exceptional physicochemical characteristics of MOF nanocomposites, it is possible to create and modify photocatalytic nanocomposites in a way that improves their recovery, efficiency, and recyclability.

Abstract This study aimed to isolate Streptomyces sp. from Moroccan terrestrial ecosystems and identify bioactive compounds through GC–MS analysis. Antimicrobial activity was assessed against various pathogenic microorganisms including Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853, Escherichia coli ATCC 25922 and Candida albicans ATCC 60193, and multi-drug resistant strains comprising Listeria monocytogenes, Klebsiella pneumoniae 19K 929, Proteus sp. 19K1313, Klebsiella pneumoniae 20B1572, Proteus vulgaris 16C1737, and Klebsiella pneumoniae 20B1572. Based on the results of the gene sequencing of gene 16S rRNA and phylogenetic analysis, the E2 isolate belongs to the genus Streptomyces with the highest degree of resemblance (97.51%) to the Streptomyces africanus strain NBRC 101005 (NR_112600.1). The isolate exhibited broad-spectrum antibacterial activity, with maximum efficacy against Klebsiella pneumoniae 20B1572 indicated by an inhibition zone diameter of 22.5 ± 0.71mm and a minimum inhibitory concentration (MIC) of 0.0625 mg/mL. The in vitro antioxidant potential of E2 strain was determined through screening of its ethyl acetate extract against sets of antioxidant assays. The results were indicative of E2 strain displaying strong antioxidant activity against ABTS, DPPH free radicals, and FRAP. Furthermore, there was a high significant correlation (p

Abstract In this research, active packaging which was made of all-natural component hydrogels from nanocellulose composited with silver nanoparticles at various concentrations (AgH) was studied. The concentration of silver nanoparticles ranged from 0.0078 to 0.0624 phr. AgH was characterized in terms of basic properties, functional properties, and packaging applications. Biocompatibility testing with the Caco-2 cell line showed that higher concentrations of silver (higher than 0.0312 phr) provided a lower cell viability rate (lower than 70% cell viability). Here, 0.0156 phr of silver nanoparticle concentration was the maximum loading that is safe for the target cell (82% cell viability) and was thus selected for use as active packaging. The antimicrobial activity showed that AgH at all concentrations inhibited both Gram bacteria up to 99.99%. Total volatile basic nitrogen compound testing showed that chicken meat preserved by AgH had the lowest values, indicating that AgH can prolong the shelf life in freshness level 1 (15% TVB-N) for 6.2 days compared to 3.9 and 4.1 days of blank and neat cellulose hydrogel. In addition, all AgH were gradually degraded over time and eventually disappeared within 15–30 days in organic soil.

Abstract Nanoparticles have gained worldwide attention as a new alternative to chemical control agents due to their special physiochemical properties. The current study focused on the environmentally friendly synthesis of silver nanoparticles (AgNPs) using Lycopersicon esculentum peel. In addition to studying the intrinsic cytotoxic effectiveness of Le-AgNPs contribute to their antibacterial, and antifungal activities and the effect of nanoparticles on the integrity of their morphological behavior. The initiative biosynthesis of L. esculentum silver nanoparticles (Le-AgNPs) was indicated by the color change of L. esculentum (Le) extract mixed with silver nitrate (AgNO3) solution from faint pink to faint brown. UV–visible spectroscopy, Dynamic light scattering (DLS), Fourier-transform infrared spectroscopy, high-resolution transmission electron microscopy (HR-TEM), and X-ray diffraction techniques were used to characterize biosynthesized Le-AgNPs. Results of UV–visible spectroscopy recorded surface plasmon resonance at 310 nm for SPR of 2.5. The DLS results showed particles of 186 nm with a polydispersity index of 0.573. The FTIR spectrum indicated the existence of carboxyl, hydroxyl, phenolic, and amide functional groups. The HR-TEM analysis revealed quasi-spherical crystal particles of Le-AgNPs. Le-AgNPs had a negative zeta potential of − 68.44 mV, indicating high stability. Bacillus subtilis ATCC 6633 and Escherichia coli ATCC 8739 were the most susceptible pathogens to Le-AgNPs inhibition, with inhibition zone diameters (IZDs) of 4.0 and 0.92 cm, respectively. However, Listeria monocytogenes NC 013768 and Shigella sonnei DSM 5570 were the most resistant pathogens, with IZDs of 0.92 and 0.90 cm, respectively. Le-AgNPs demonstrated good inhibitory potential against pathogenic fungi, with IZDs of 3.0 and 0.92 cm against Alternaria solani ATCC 62102 and Candida albicans DSM 1386, respectively. The cytotoxicity effect was observed at a half-maximal inhibitory concentration (IC50) of 200.53 μg/ml on human colon NCM460D normal cells.

The tangerine, or Citrus reticulata Blanco, is a citrus fruit that dates back several centuries and is valued for its many nutrients and bioactive compounds that can have medicinal effects. The tangerine is valued for its many biological properties, which include anti-inflammatory, anti-cancer, anti-hyperlipidemic, anti-diabetic and antioxidant properties in addition to its great taste. The many phytochemicals found in tangerines, such as organic acids, sugars and amino acids, as well as secondary metabolites including flavonoids, phenolic acids, carotenoids and polyphenols, are responsible for these health benefits. The aim of this study is to assess the antibacterial efficacy of C. reticulata Blanco against specific plant pathogenic bacteria such as Xanthomonas arboricola CCM 1441, Pectobacterium carotovorum CCM 1008, Pseudomonas putida CCM 7156, Bacillus subtilis CCM 2217, Priestia (Bacillus) megaterium CCM 2007. In our investigation, two approaches were used to measure antimicrobial activity. The antimicrobial activity of the investigated bacterial strains was compared using the disc diffusion method under in vitro conditions and their antibiotic resistance was also evaluated. The antimicrobial activity under in situ conditions was a species approach applied to the surface of carrots. The essential oil of C. reticulata Blanco was found to have the strongest in vitro antibacterial activity against P. megaterium. In addition, in situ monitoring of the antimicrobial activity was carried out, with the highest results obtained against P. megaterium at a concentration of 125 µg/L. According to the present investigation, C. reticulata Blanco essential oil significantly inhibited the growth of various Gram-positive and Gram-negative bacteria.

Citrus essential oils (EOs) are used industrially in a wide range of products such as food and beverages, cosmetics and medicines. They are also used to combat some of the most important plant and food diseases. Citrus EOs are mostly found in fruit peels, which makes their extraction economically viable as fruit peels are wasted in the production of fruit juices. The aim of this study was to evaluate EO from Citrus nobilis, which was extracted by cold pressing of unripe pericarp, in terms of their ability to suppress the most prevalent plant diseases. The disc diffusion method was used to determine the antibacterial activity against plant diseases under in vitro conditions. It was found that the lowest concentration of EO had the best antibacterial effect against Bacillus subtilis in the vapor phase on the carrot model. The results of our experiments showed that C. nobilis EO had moderate antimicrobial activity.

Background: Antibiotic use has been rising in both humans and animals. The growing concern over antimicrobial drug resistance and the promotion of regional drug use have led to a rising in the interest medicinal applications of herbs combined with biosynthesized nanoparticles. Aim: To evaluate the antimicrobial and acaricidal effects of Syzygium cumini leaves crude extract (Sc-CE) and biosynthesized S. cumini silver nanoparticles (Sc-AgNPs) on dog skin pathogens and determined the optimal concentration and time for in vitro application. Methods: S. cumini leaves (Sc) were prepared as Sc-CE and Sc-AgNPs. The biosynthesized silver nanoparticles were characterized employing various techniques, including dynamic light scattering (DLS), scanning electron microscopy (SEM), and energy-dispersive X-ray analysis (EDAX). Phytochemical analyses were conducted using liquid chromatography coupled with quadrupole time-of-flight mass spectrometry screening (LC/QTOF-MS). Antimicrobial activity was examined against gram-positive bacteria, including Staphylococcus aureus and Staphylococcus pseudintermedius, gram-negative bacteria such as Pseudomonas aeruginosa, yeast strains including Malassezia pachydermatis and Candida albicans, and ectoparasite. Cytotoxicity was evaluated on canine primary dermal fibroblast (CPDF) using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Results: The Sc-AgNPs exhibited nanoparticle sizes ranging from 100 to 350 nm with aggregated spherical shape and contained Ag element in this nanoparticle. Myricetin and Phloretin were among the extracted compounds, contributing to the reduction of pathogenic organisms. Sc-AgNPs showed high efficacy against skin pathogens compared to Sc-CE, with lower cytotoxicity effect on CPDF. Conclusion: The Sc-AgNPs demonstrated superior efficiency against pathogens in dog skin diseases as both concentration- and time-dependent and were deemed safe to CPDF within 24h. [Open Vet J 2024; 14(10.000): 2662-2677]

Abstract Treatment of bacterial infections with antibiotic resistance is complicated. For this reason, new therapeutic methods are needed to control bacterial infections. Therefore, it is necessary to discover new antibiotics from medicinal plants that can destroy drug-resistant bacteria. Essential oils (EO) of some medicinal plants have antimicrobial effects and can be used as antimicrobial agents in the treatment of infections and food industries. The aim of this study was to determine the EO composition and antimicrobial effects of EO and polyphenols profile of Salvia Sahendica roots for the first time. Chemical compounds and antibacterial activity of EOs against Staphylococcus aureus and Bacillus cereus as gram-positive and Escherichia coli and Pseudomonas aeruginosa as gram- negative bacteria were evaluated using microtiter broth dilution method. Studied organs of S. sahendica showed significant diversity in terms of type and percentage of essential oil and polyphenol compounds. Overall, 44, 46, 42, and 45 compounds were identified in the essential oil of leaves, flowers, stems, and roots of this plant, which constituted 99.6, 99.3, 98.2, and 99.4% of total oil composition, respectively. The current study collectively demonstrated inhibitory effects ranged from strong (S. aureus) to low inhibition (P. aeruginosa). According to the HPLC result, the amounts of coumaric acid, chlorogenic acid, and gallic acid compounds in the root are higher than in other plant parts, which indicate that the root can be a suitable source for the production of these valuable polyphenol compounds. Due to the results, it is possible to hope for the application of EO from S. sahendica as natural antibacterial in the pharmaceutical and food industries.

Abstract Bitter gourd wilt, a severe vascular disease triggered by the soilborne pathogen Fusarium oxysporum f. sp. momordicae (FOM), markedly constrains bitter gourd yield. In this study, a novel strain BF19 of Brevibacillus brevis was isolated and identified, exhibiting strong antimicrobial activity against FOM through in vivo and in vitro experiments. To comprehensively assess the biocontrol potential of strain BF19, we conducted phenotypic, phylogenetic, and comparative genomics analyses. Phenotypic analysis revealed that BF19 exhibited 53.33% biocontrol efficacy and significantly increased the average plant height, root fresh weight, and dry weight. Whole-genome sequencing and comparative genomic analysis revealed numerous potential genes associated with biocontrol mechanisms in BF19. Importantly, the integration of metabolic cluster prediction with liquid chromatography‒tandem mass spectrometry (LC‒MS/MS) revealed the presence of a macrobrevin antibiotic, a product of polyketide synthases (PKSs), predominantly in BF19 fermentation products. The effectiveness of the Br. brevis strain BF19 and its crude extract against bitter gourd wilt has also been confirmed. This study provides a genetic framework for future investigations on PKSs and establishes a scientific basis for optimizing field applications of microbial biopesticides derived from Br. brevis BF19.

Continuous use of synthetic fungicides has led to explosive emergence of fungicide-resistant microbes. Therefore, there are urgent needs for environmentally friendly antimicrobial agents with novel modes of action. This study investigated endolichenic fungi (ELF) as a source of antimicrobial compounds against various plant pathogens. We utilized an One Strain MAny Compounds (OSMAC) approach to enhance the chemical diversity of fourteen ELF. This involved cultivation of ELF in four growth media and subsequently assessing antimicrobial activities of culture extracts. Nearly half of the culture extracts exhibited antimicrobial activity against a Gram-positive bacterium, but showed minimal activity against Gram-negative bacteria tested. Notably, culture extracts from two ELF, Chaetomium globosum and Nodulisporium sp., demonstrated significant inhibitory effects against plant pathogenic fungi. LC-MS/MS-based metabolome profiling confirmed the presence of known bioactive compounds like cyclic dipeptides and chaetoglobosins. These findings highlight the effectiveness of combining OSMAC and metabolomics for identifying antimicrobial agents for agricultural use.

Zifang Shang,1,* Vipasha Sharma,2,* Tarun Kumar,3 Kamal Dev,4,5 Sandip Patil6 1Guangdong Engineering Technological Research Center of Clinical Molecular Diagnosis and Antibody Drugs, Meizhou Academy of Medical Sciences, Meizhou People’s Hospital (Huangtang Hospital), Meizhou, 514031, People’s Republic of China; 2Department of Biotechnology, University Institute of Biotechnology, Chandigarh University, Mohali, Punjab, India; 3Mkelly Biotech Pvt Ltd., Mohali, Punjab, India; 4Faculty of Applied Sciences and Biotechnology, Shoolini University of Biotechnology and Management Sciences, Solan, Himachal Pradesh, India; 5Department of Pharmacology and Toxicology, Wright State University, Dayton, OH, USA; 6Department of Haematology and Oncology, Shenzhen Children’s Hospital, Shenzhen, People’s Republic of China*These authors contributed equally to this workCorrespondence: Sandip Patil; Vipasha Sharma, Email sandippatil1309@yahoo.com; sharma.vipasha@gmail.comBackground: The global threat of multi-drug-resistant bacteria has severely limited the options available for effective antibiotics. This study focuses on the antimicrobial activity and phytochemical characterization of C. oppositifolia extracts, aiming to identify novel plant-based therapeutic agents.Methods: C. oppositifolia specimens-leaves and inflorescence. Specimens were cleaned, sterilized, dried, and ground into a fine powder. Extracts were obtained using methanol and petroleum ether via a Soxhlet apparatus, followed by fractionation with chloroform, n-butanol, and ethyl acetate. Volatile oil was extracted through hydro distillation using a Clevenger apparatus. Phytochemical analysis was conducted to identify bioactive compounds. Biophysical techniques, including UV-visible spectrophotometry, TLC, HPLC, GC-MS, FTIR, and NMR, were employed for characterization. Antimicrobial activity was tested against S. aureus ATCC25922 and E. coli ATCC25922 using agar well and disc diffusion methods, and synergistic effects were assessed with erythromycin and amoxicillin.Results: Methanol extract exhibited bacteriostatic activity with inhibition zones of 13.0 ± 0.2 mm for both S. aureus and E. coli. Petroleum ether, chloroform, n-butanol, and ethyl acetate fractions showed varying inhibition zones. Erythromycin demonstrated bactericidal activity, which was enhanced synergistically when combined with methanol extract and volatile oil, increasing inhibition zones against S. aureus. Phytochemical analysis identified phenols, flavonoids, tannins, coumarins, alkaloids, terpenoids, saponins, and glycosides. FTIR analysis revealed functional groups such as amines, aldehydes, nitriles, alkenes, and sulfones. GC-MS identified 24 compounds, with α-pinene, caryophyllene, and carene as major components. NMR spectra indicated no complex formation between oils and antibiotics, suggesting the compounds act as synergists.Conclusion: The C. oppositifolia extracts possess significant antimicrobial activity and synergistic potential, particularly against S. aureus. The presence of various bioactive compounds suggests a promising role in developing new plant-based therapeutics.Keywords: C. oppositifolia, antimicrobial activity, phytochemical characterization, multidrug-resistant pathogens, synergistic effects

Abstract This study aimed to optimize the production of carotenoid pigments from Micrococcus luteus (ATCC 9341) through the statistical screening of media components and the characterization of antimicrobial, antioxidant, cytogenetic and cytotoxic activities. A BOX-Behnken design was used to assess the effects of whey concentration, inoculum size, pH, temperature, and agitation speed on carotenoid yield. The optimum combination increased production to 2.19 g/L, with a productivity of 0.045 g L-1 h−1 and a productivity yield of 0.644 g/g, as confirmed by an observed carotene production of 2.19 g/L. The final response surface model fitting the data had an R2 of 0.9461. High-performance liquid chromatography (HPLC) analysis identified 12 carotenoid pigment compounds produced by M. luteus. The extracts displayed moderate antimicrobial efficacy against Gram-positive bacteria such as Bacillus cereus (ATCC 11778), Staphylococcus aureus (ATCC 6538), and E. faecalis (ATCC 19433), with inhibition zone diameters (IZD) of 29.0, 14.0, and 37.0 mm, respectively, at 1000 μg/mL. However, its effectiveness against Gram-negative bacteria is limited. In comparison, tetracycline exhibited greater antimicrobial potency. The IC50 value of carotenoids was used to indicate the antioxidant activity. IC50 value from the DPPH assay was 152.80 mg/100mL. An IC50 cytotoxicity value greater than 300 μg/mL was found against normal mouse liver cells, with over 68% cell viability even at 300 μg/mL, indicating low toxicity. Histological structure studies revealed normal myocardial muscle tissue, lung tissue, and kidney tissue sections, whereas liver tissue sections revealed ballooning degeneration of hepatocytes and disorganization of hepatic cords. Cytogenetic parameters revealed that the carotene treatment group had a mitotic index (70%) lower than that of the control but higher than that of the positive control, mitomycin, and did not substantially increase numerical (1.2%) or structural aberrations compared with those of the control, suggesting a lack of genotoxic effects under the experimental conditions. In conclusion, optimized culture conditions enhanced carotenoid yields from M. luteus, and the extracts displayed promising bioactivity as moderate antibiotics against certain gram-positive bacteria and as antioxidants. The high IC50 values demonstrate biosafety. Overall, this bioprocess for enhanced carotenoid production coupled with bioactivity profiling and low cytotoxicity support the application of M. luteus carotenoids.

Abstract Chronic exposure to ultraviolet (UV) radiation can cause degenerative changes in the cells, fibrous tissues and blood vessels. Moreover, microbiological attacks pose severe risks to human health and are a major cause of sickness worldwide. The aim of this work is to develop UV protective and antimicrobial materials using zinc oxide (ZnO) colloidal solution with carrot and orange peel extract. Treated samples were subjected to color strength (K/S value) measurement, scanning electron microscope (SEM) image analysis, attenuated total reflectance (ATR) Fourier transform infrared (FTIR) spectroscopy analysis, ultraviolet protection factor (UPF) test, bacterial reduction rate analysis and bursting strength measurement. The study revealed that the treated fabric exhibited remarkable UV protection capabilities, as evidenced by low transmission percentages across UV wavelengths and an outstanding UPF rating of 50, signifying excellent defense against harmful ultraviolet radiation. Additionally, antibacterial tests revealed the significant effectiveness of the treatment against common bacterial strains, with impressive reduction rates for Staphylococcus aureus (99.99%) and Escherichia coli (99.17%). Furthermore, the fabric's bursting strength, both in dry and wet conditions, remained nearly unchanged after treatment. ATR‐FTIR analysis and SEM imaging provided insights into the phytochemical compounds that give protection against UV composition (44.63–49.91) and surface morphology of the treated fabric, elucidating the mechanisms behind its enhanced properties. Due to the availability of carrot and orange peel in nature and low cost of raw materials, this process can be considered to apply commercially for further research purposes. Highlights Utilization of carrot and orange peel waste. Successful application of zinc oxide for antibacterial and ultraviolet protective materials. Excellent defense against harmful ultraviolet radiation. Significant effectiveness against common bacterial strains. Low cost and commercially viable functional materials.

Abstract Green synthesis leverages biological resources such as plant extracts to produce cost-effectively and environmentally friendly NPs. In our study, silver nanoparticles (AgNPs) are biosynthesized using blank roasted grams (Cicer arietinum) as reducing agents. CA-AgNPs were characterized by a characteristic surface plasmon resonance (SPR) peak at 224 nm in the UV–Vis spectrum. FTIR analysis revealed functional groups with O–H stretching at 3410 cm−1, C–H stretching at 2922 cm−1, and C=O stretching at 1635 cm−1. XRD patterns exhibited sharp peaks at 33.2°, 38.4°, 55.7°, and 66.6°, confirming high crystallinity. Morphological analysis through FESEM indicated spherical CA-AgNPs averaging 500 nm in size, with EDS revealing Ag at 97.51% by weight. Antimicrobial assays showed zones of inhibition of 14 mm against Candida albicans, 18 mm against Escherichia coli., and 12 mm against Propionibacterium acnes. The total phenolic content of CA-AgNPs was 26.17 ± 13.54 mg GAE/g, significantly higher than the 11.85 ± 9.57 mg GAE/g in CA extract. The ABTS assay confirmed the antioxidant potential with a lower IC50 value of 1.73 ± 0.41 µg/mL, indicating enhanced radical scavenging activity. Anti-melanogenesis was validated through tyrosinase, showing inhibition rates of 97.97% at the highest concentrations. The anti-inflammatory was evaluated by western blot, which showed decreased expression of iNOS and COX-2. This study demonstrates the green synthesis of CA-AgNPs and its potential biomedical applications. The results of this study demonstrate that biosynthesized CA-AgNPs have key biological applications.

Abstract The auto-combustion method synthesized CuO NPs and Ag/CuO NPs. The Ag/CuO NPs were analyzed using Fourier-transform infrared, X-ray diffraction, scanning electron microscope, and Energy-dispersive X-ray spectroscopy instrumental analyses. The energy band gap, as determined by DRS properties, decreases from 3.82 to 3.50 eV for pure CuO and 10% Ag/CuO NPs, respectively. The photodegradation efficiency of Rhodamine-B & Carmine by 10% Ag/CuO NPs was nearly 98.9 and 97.8%, respectively. Antimicrobial trials revealed that the antimicrobial efficacy of Ag/CuO NPs at several dosages (20, 40, 60, 80, 100, and 120 µg/mL) against human pathogens was initially assessed using the agar well-diffusion method, and then the broth dilution method. Noticeably, the minimum inhibitory concentration of Ag/CuO NPs for all pathogens ranged from 100 to 120 µg/ml, was determined. Generally, the observed minimum microbicide concentration has a wide range of Ag/CuO NPs doses, ranging from 150 to 300 µg/ml, which helps kill (99.99%) all tested pathogenic cells. The largest relative inhibitory activities (%) were recorded against Escherichia coli (81.45 ± 1.39) at 120 g/mL of Ag/CuO NPs and 100 μg/mL (80.43 ± 0.59), followed by 80 µg/mL (72.33 ± 0.82). Additionally, the lowest relative inhibitory activities (%) were monitored versus fungal cells and Gram-positive bacteria at 120 µg/mL of Ag/CuO NPs as 52.17 ± 1.49 and 53.42 ± 1.71; respectively. Graphic abstract

Abstract Herbal medicines are important for ensuring sustainable development goals (SDGs) in healthcare, particularly in developing countries with high rates of antimicrobial resistance (AMR) and little access to medical facilities. Thymus vulgaris is a widely used herbal medicinal plant known for its secondary metabolites and antimicrobial properties. The present study involved a comprehensive examination of the isolation, characterization, and antibacterial activity of Thymus vulgaris obtained from Ethiopia. The aerial part of the plant Thymus vulgaris was successively extracted with hexane, chloroform, and methanol based on differences in polarity. Phytochemical screening tests conducted against hexane, chloroform and MeOH crude extracts indicated the presence of some secondary metabolites. Based on the thin-layer chromatography tests, the chloroform extract was subjected to column chromatography, yielding Tv-2 compounds, namely 5-isopropyl-2-methylphenol. The structures of the compounds were elucidated via spectroscopic methods (UV–Vis, FT-IR and NMR). We investigated the antibacterial properties of hexane crude extract, chloroform crude extract, MeOH crude extract, and isolated fractions derived from T. vulgaris against various bacterial strains. This study contributes to a better understanding of the bioactive components present in Thymus vulgaris crude extracts and their potential role in tackling microbial infections.

For millennia, people have successfully treated a wide range of illnesses, including bacterial infections, with different plant parts or extracts. “MDR strain” typically refers to a “multi-drug resistant strain” of a bacteria. In the context of infectious diseases, a multi-drug resistant strain refers to a strain of the pathogen that has acquired resistance to multiple drugs that are commonly used to treat infections caused by that specific pathogen. MDR strains can present significant challenges in healthcare settings as they limit the effectiveness of standard treatments and may require more aggressive or specialized approaches to manage the infection. The discdiffusion method was used in this investigation to test the antimicrobial properties of Petroleum ether, acetone, ethanol, methanol, and aqueous extracts of Ficus auriculata leaves against four bacterial strains namely Salmonella enteric serovar typhi, Salmonella enteric ser Paratyphi (MDR strain) Pseudomonas aeruginosa and Escherichia coli. The findings showed that all of the investigated organisms (zone of inhibition of 0.5 ± 0.15 & 18 ± 1.7 mm) were significantly inhibited by the petroleum ether, ethanol, and methanol extracts, with the exception of Salmonella typhi (an 18 mm inhibitory zone). The restricted area (≤5) indicated moderate activity in the aqueous extracts. It’s crucial to remember that antimicrobial activity analysis of plant extracts is just one step in the process of identifying potential natural antimicrobial agents. Further studies, including the identification and isolation of specific bioactive compounds, toxicology assessments, and clinical trials, are required before any plant extract can be considered for use as a drug development.

Bacteriocins are proteins secreted by many species of bacteria to inhibit other bacteria, thus eliminating competitors to gain resources. Bacteria from the Lactobacillus group are known for their applications as probiotics and food preservatives. They have earned a reputation for producing substances that inhibit the growth of other microorganisms, which include organic acids, diacetyl, and bacteriocins. Produced by the ribosomes, bacteriocins are cationic proteins that inhibit other bacteria coexisting within a shared ecological habitat. Due to their potential uses in a variety of applications large-scale production of Bacteriocins would be necessary. The study aimed to identify and characterize Lactobacillus bacteria that produce potent bacteriocins and to analyze the antimicrobial activity and stability of the isolated bacteriocin under various physical and biochemical conditions. A total of 50 samples including buffalo dung, cheese, and rhizospheric region of plants were screened to isolate 8 Lactobacillus Li-1, Li-2, Li-3, Li-4, Li-5, Li-6, Li-7, and Li-8, confirmed by gram staining and other biochemical tests. The cell free supernatant from the Li-3 strain showed higher inhibition of Escherichia coli and Staphylococcus aureus, as compared to the other isolated strains. Li-3 strain was further identified as Levilactobacillus brevis strain ABRIINW-K by 16S rRNA gene sequencing. The bacteriocin isolated from this strain is a thermostable peptide (~6kDa), which is characteristic of class II bacteriocins, with potent antibacterial activity against Lactobacillus rhamnosus, Escherichia coli, and Salmonella enterica.

The study presents a detailed investigation of the essential oil obtained by distilling the stems of Pelargonium roseum, also known as geranium oil, cultivated at the bio-farm of the Faculty of Pharmacy in Galați, Romania. Interest in this study was sparked by the potential applications of the oil in interdisciplinary fields such as pharmacy and dentistry, considering the diversity and varying concentrations of its phytoconstituents. The research is notable for focusing on the compositional analysis of oils obtained during the pandemic years 2020, 2021, and 2022, periods marked by the global SARS-CoV-2 health crisis. The chosen methodology for the detailed analysis of the oil components includes gas chromatography coupled with mass spectrometry, using the Adams protocol for precise identification and quantification. The mass spectra obtained were compared with those from the Wiley standard library, facilitating a rigorous evaluation of the chemical profiles. The main findings indicate a predominance of monoterpene alcohols – citronellol, geraniol, and linalool – present in free or esterified forms. Citronellol, in particular, stands out due to its high concentrations, conferring notable antibacterial and antifungal properties to the oil, superior to other volatile oils analyzed. This feature recommends it as a promising candidate for medical applications, especially in dentistry. Based on the results, the study proposes an in-depth exploration of the antibacterial efficacy of geranium oil, aiming at the development of new pharmaceutical preparations with controlled release. These preparations could enhance current treatments by offering efficient natural alternatives for preventing and combating bacterial and fungal infections in dental practice. Thus, the study emphasizes the importance of continuing research in this field, highlighting the valuable potential of essential oils in modern medical applications.

Abstract Cinnamaldehyde (CIN), a harmless bioactive chemical, is used in bio-based packaging films for its antibacterial and antioxidant properties. However, high amounts can change food flavor and odor. Thus, ZnO nanoparticles (NPs) as a supplementary antimicrobial agent are added to gelatin film with CIN. The CIN/ZnO interactions are the main topic of this investigation. FTIR-Attenuated Total Reflection (ATR), X-ray diffraction (XRD), and scanning electron microscopy (SEM) were utilized to investigate CIN/ZnO@gelatin films. Transmission electron microscope (TEM) images revealed nanospheres morphology of ZnO NPs, with particle sizes ranging from 12 to 22 nm. ZnO NPs integration increased the overall activation energy of CIN/ZnO@gelatin by 11.94%. The incorporation of ZnO NPs into the CIN@gelatin film significantly reduced water vapour permeability (WVP) of the CIN/ZnO@gelatin film by 12.07% and the oxygen permeability (OP) by 86.86%. The water sorption isotherms of CIN/ZnO@gelatin were described using Guggenheim-Anderson-de Boer (GAB) model. The incorporation of ZnO NPs into the CIN@gelatin film reduced monolayer moisture content (M 0) by 35.79% and significantly decreased the solubility of CIN/ZnO@gelatin by 15.15%. The inclusion of ZnO into CIN@gelatin film significantly decreased tensile strength of CIN/ZnO@gelatin by 13.32% and Young`s modulus by 18.33% and enhanced elongation at break by 11.27%. The incorporation of ZnO NPs into the CIN@gelatin film caused a significant decrease of antioxidant activity of CIN/ZnO@gelatin film by 9.09%. The most susceptible organisms to the CIN/ZnO@gelatin film included Candida albicans, Helicobacter pylori, and Micrococcus leutus. The inhibition zone produced by the CIN/ZnO@gelatin film versus Micrococcus leutus was 25.0 mm, which was comparable to the inhibition zone created by antibacterial gentamicin (23.33 mm) and cell viability assessment revealed that ZnO/CIN@gelatin (96.8 ± 0.1%) showed great performance as potent biocompatible active packaging material.

Abstract Caesalpinia sappan L. has generally been used in Asian folk medicines for disease treatment. C. sappan heartwood is commonly utilized as a dyeing agent in food items, beverages, cosmetics, and clothing. The effects of three extraction techniques (maceration, reflux, and ultrasonic-assisted extraction) of C. sappan heartwood extract (CSE) on the brazilin content and potential of biological activities were investigated. The brazilin content was determined using high-performance liquid chromatography (HPLC). Quantifications of the antioxidant properties (DPPH and ABTS), the total phenolic contents, and the antimicrobial activity were also examined. Additionally, the effect of CSE on pro-inflammatory cytokine and mediator production was investigated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophage cells. The results showed that the CSE from the maceration and reflux methods produced high levels of brazilin and total phenolic contents, as well as having excellent antioxidant and antimicrobial activities. The macerated extract showed significant antioxidant activities with IC50 values of 2.88 ± 0.01 and 0.32 ± 0.01 mg/mL from DPPH and ABTS assays, respectively. Furthermore, the CSE from the maceration method which was rich in brazilin had an anti-inflammatory response by decreasing the levels of nitric oxide (NO), interleukin (IL)-6, and tumor necrosis factor (TNF)-α on LPS-stimulated RAW 264.7 macrophage cells. These results confirmed CSE as a potential source of biological components. Antioxidant and anti-inflammatory assays proved maceration was the best extraction method.

This study aims to present knowledge on therapeutic potential bacteriocin producing bacterial strains. Samples (n=35) from diverse Ernakulam sources yielded 26 lactic acid bacteria (LAB) isolates on De Man Rogosa Sharpe (MRS) medium. Among the isolates potent antimicrobial activity observed against known pathogens in one of the isolates from goat milk sample number 3, labelled as GO3. Microscopic and biochemical test revealed the isolate is Gram-positive rod, non-sporulating and resilience to pH and bile salts, with adaptability to gastric enzymes and surfactants. Genetic and physiological traits of the positive strains were confirmd by 16S rRNA technique. Blast analysis revealed that sequence of the strain GO3 from goat milk identified as Lactobacillus casei, exhibited antibiotic sensitivity, auto-aggregation, co-aggregation, and antibiofilm assays highlighted inhibitory properties as a promising therapeutic potential probiotic bacterium. LAB isolates can be further investigated at the genetic level to enhance their probiotic characteristics such as resistance and cellular adhesion. Additionally, the identification of gene responsible for expressing bacteriocins can be conducted on these isolates.

Abstract This study addresses the critical need for efficient and sustainable methods to tackle organic pollutants and microbial contamination in water. The present work aim was to investigate the potential of multi-structured zinc oxide nanoparticles (ZnO NPs) for the combined photocatalytic degradation of organic pollutants and antimicrobial activity. A unique fusion of precipitation-cum-hydrothermal approaches was precisely employed to synthesize the ZnO NPs, resulting in remarkable outcomes. The synthesized CTAB/ZnO NPs demonstrated exceptional properties: they were multi-structured and crystalline with a size of 40 nm and possessed a narrow band gap energy of 2.82 eV, enhancing light absorption for photocatalysis. These nanoparticles achieved an impressive degradation efficiency of 91.75% for Reactive Blue-81 dye within 105 min under UV irradiation. Furthermore, their photocatalytic performance metrics were outstanding, including a quantum yield of 1.73 × 10–4 Φ, a kinetic reaction rate of 3.89 × 102 µmol g–1 h–1, a space–time yield of 8.64 × 10–6 molecules photon–1 mg–1, and a figure-of-merit of 1.03 × 10–9 mol L J–1 g–1 h–1. Notably, the energy consumption was low at 1.73 × 10–4 J mol–1, compared to other systems. Additionally, the ZnO NPs exhibited effective antimicrobial activity against S. aureus and P. aeruginosa. This research underscores the potential of tailored ZnO NPs as a versatile solution for addressing both organic pollution and microbial contamination in water treatment processes. The low energy consumption further enhances its attractiveness as a sustainable solution.

Abstract This study proposes an innovative approach to combat the escalating threat of antibiotic resistance in bacteria by introducing a novel ZnO-propolis nanocomposite (ZnO-P NCs). The overuse of antibiotics, particularly during events like the COVID-19 pandemic, has intensified bacterial resistance, necessitating innovative solutions. The study employs a cost-effective and controllable biosynthesis method to produce ZnO nanoparticles (ZnO-NPs), with propolis extract crucially contributing to the reduction and stabilization of Zn2+ ions. A biodegradable nano-propolis matrix is then created by incorporating ZnO-NPs, forming the ZnO-P NCs. Structural stability is confirmed through FT-IR and Zeta potential analysis, while nanoscale properties are validated via TEM, SEM, and XRD analyses. The antimicrobial efficacy of various substances, including propolis, nano propolis, ethanolic propolis extract, ZnO-NPs, and ZnO-P NCs, is assessed against Gram-negative and Gram-positive bacteria, alongside a comparison with 28 antibiotics. Among the bacteria tested, Pseudomonas aeruginosa PAO1 ATCC15692 was more sensitive (40 mm) to the biosynthesized nanocomposite ZnO-P NCs than to ZnO-NPs (38 mm) and nanopropolis (32 mm), while Escherichia coli was resistant to nanopropolis (0 mm) than to ZnO-NPs (31 mm), and ZnO-P NCs (34 mm). The study reveals a synergy effect when combining propolis with green-synthesized ZnO-NPs in the form of ZnO-P NCs, significantly improving their efficiency against all tested bacteria, including antibiotic-resistant strains like E. coli. The nanocomposite outperforms other materials and antibiotics, demonstrating remarkable antibacterial effectiveness. SEM imaging confirms the disruption of bacterial cell membranes by ZnO-NPs and ZnO-P NCs. The study emphasizes the potential applications of ZnO-NPs integrated into biodegradable materials and underscores the significance of the zinc oxide-propolis nanocomposite in countering antimicrobial resistance. Overall, this research offers a comprehensive solution to combat multidrug-resistant bacteria, opening avenues for novel approaches in infection control.

This study investigated the bioactive substance contents within extracts derived from different parts of Lonicera japonica Thunb. and assessed their bacterial inhibitory activities against 12 test strains. Initially, the concentrations of total phenols, total flavonoids, and chlorogenic acid were determined in Lonicera japonica leaves, Lonicerae japonica Flos, and Lonicera japonica caulis. Subsequently, the bacterial inhibition profiles of their extracts against 12 test strains were analyzed. Building upon this analysis, the effects of Lonicerae japonica Flos and Lonicera japonica leaves extracts on minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), growth curve, biofilm formation, and cell morphology of Alicyclobacillus acidoterrestris were further investigated. Results revealed that the concentrations of total phenols, total flavonoids, and chlorogenic acid in L. japonica leaves and L. japonica Flos were significantly higher than those from L. japonica caulis (P

The main novelty of this research lies in combining natural fibers and mineral fillers to create a sustainable material with enhanced antimicrobial and structural properties, offering promising applications in various industries requiring eco-friendly and high-performance materials. This study investigates the fabrication and analysis of a green composite made from Cannabis sativa fiber reinforced (CSFR) with granite filler in an epoxy matrix, focusing on antimicrobial properties and structural integrity. Various amounts of granite powder (0, 3, 6, 9, 12, and 15 g) were incorporated into the epoxy matrix. The composite exhibited significant antibacterial activity was observed against E. coli. Mechanical testing revealed that the composite with 12 g of granite powder showed the best performance, with tensile strength improving by 11.4%, flexural strength by 12.3%, impact strength by 29% and hardness is improved by 17.5%. SEM analysis highlighted well-dispersed particulates and strong fiber-matrix bonding at optimal filler levels. TGA showed enhanced thermal stability, with the decomposition onset shifting from 240 °C to 280 °C and weight retention improving 90% at 350 °C. This study underscores the potential of Cannabis sativa fiber reinforced granite filler epoxy matrix composites as sustainable materials with excellent antimicrobial and structural properties for advanced applications.

Of several noble metal nanoparticles, silver nanoparticles (AgNPs) have attracted special attention due to their distinct properties, such as favorable electrical conductivity, chemical stability, and catalytic and antibacterial activities. Green synthesis of AgNPs using plant extracts containing phytochemical agents has attracted considerable interest. This environmentally friendly approach is more biocompatible and cost-efficient and has the capability of supporting large-scale synthesis. This study developed an eco-friendly method for the preparation of AgNPs using the aqueous leaf extract of Saussurea obvallata as reducing and capping agents. Ultraviolet visible spectroscopy (UV–Vis), Fourier transform infrared spectroscopy (FTIR), Raman, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) analyses were conducted to characterize the synthesized AgNPs. The morphology of AgNPs was found to be spherical with an average crystallite size of 12 nm and a maximum absorbance at 410 nm. 10 mg of AgNPs had potential to reduce 4-nitrophenol to 4-aminophenol in 16 min and exhibited strong biological activities against the Gram-negative bacteria Escherichia coli (12 mm) and Gram-positive bacteria Enterococcus faecalis (13 mm). The antioxidant activity of the synthesized AgNPs was investigated against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and exhibited up to 61.21% ± 0.02% at an AgNPs concentration of 500 μg/mL.

Preventing food spoilage and prolonging its shelf life are of great importance to meet the increasing food demand. Dietary fibers in red pitahaya are known to help maintain food freshness. Lactic acid bacteria have probiotic properties and can be a good alternative to additives in food production. Therefore, we aimed to investigate the potential use of gum-based edible films containing red pitahaya extract and probiotic as a coating material in the food industry. Firstly, we determined the antimicrobial activity of red pitahaya peel and flesh extracts against pathogenic microorganisms and probiotic strains. Then, we employed the well diffusion method to determine the antimicrobial activity of the edible films containing red pitahaya extracts and Limosilactobacillus fermentum MA-7 used as a probiotic strain. The largest inhibition zone diameters of peel and flesh extracts were 12.97 and 13.32 mm, respectively, against Candida albicans ATCC 10231. The inhibition of the growth of lactic acid bacteria was lower as the extract concentration decreased. The gum-based films with flesh extract and probiotic had the largest inhibition zone diameters of 21.63 and 21.52 mm, respectively, against Aeromonas hydrophila ATCC19570 and C. albicans ATCC 10231. The edible films containing red pitahaya extract and L. fermentum MA-7 may have the potential to prevent spoilage caused by microorganisms in the food industry and to extend the shelf life of foods.

Essential oils (EOs) and nature identical compounds (NICs) express different antimicrobial activity (AAc) which can be affected by variability in composition, stability over time, and the carrier employed for their inclusion in feedstuff and products for animal treatments. The aim of the present study was to evaluate the stability over time of the AAc of 8 EOs and 5 NICs, alone and in combination with Tween 20, on four major bacterial livestock pathogens (E. coli, S. Typhimurium, S. aureus and MRSA). For this purpose, minimal inhibitory concentration (MIC) and checkerboard assay (CkA) tests were performed on EOs and NICs at batch first use (T0 – only MIC), and after 12 (T1) and 24 (T2) months. Several EOs showed initial MICs lower than 2% (v/v) and, except for clove bud and cinnamon EOs, reduced their efficacy over time. The best NICs’ AAc was showed at T1 by cinnamic aldehyde (against MRSA), carvacrol (against E. coli), and thymol (except against MRSA), while at T2 the MIC values decreased for most of the NICs. The CkA between EOs and Tween 20 showed different interactions (Fractional Inhibitory Concentration -FIC- index from 0.06 to 32.04) based on bacteria and time. No interactions were found between NICs and Tween 20 (FIC index from 1.0 to 3.0). The AAc of EOs and NICs changes over time. Therefore, the preservation interval of these additives is critical for the AAc of feedstuff and products intended for livestock animals. Moreover, the NICs seem more suitable for the association with Tween 20.

This study aimed to investigate the effectiveness of a composite film comprising nano chitosan and Iranian tragacanth gum (NC-G), supplemented with Eryngium campestre essential oil (EO), in preserving the microbial quality of refrigerated goat meat at 4°C. Five film treatments were prepared, including NC + NC-G, and NC-G combined with 0.5%, 1%, and 1.5% EO. The antimicrobial efficacy of these films was evaluated against four microorganisms. Subsequently, these film treatments, along with an untreated control, were monitored for microbial changes [total viable count (TVC), psychrotrophic count (PTC), lactic acid bacteria, and Enterobacteriaceae] over a 16-day storage period. Results demonstrated significant antimicrobial activity of the films against tested pathogens, with effectiveness increasing with higher EO concentrations (p< 0.05). Staphylococcus aureus showed the highest susceptibility among the bacteria, while Pseudomonas aeruginosa exhibited the greatest resistance. Application of the nanocomposite film with EO effectively delayed microbial spoilage of goat meat, with TVC and PTC counts in treatments containing 1% and 1.5% EO remaining below the spoilage threshold (7 Log CFU/g) by the end of storage. Overall, findings suggest that incorporating EO into the nanocomposite film inhibits factors contributing to microbial spoilage in goat meat. Given similar inhibitory effects observed at 1% and 1.5% EO concentrations and considering economic factors, a concentration of 1% EO can be regarded as optimal.

Background: Eichornia crassipes and Pistia stratoites are aquatic weeds that contain various antimicrobial compounds and have the potential to disinfectants. Objective: This study aims to analyze the antimicrobial activity of extract of Eichornia crassipes and Pistia stratoites as In Vitro disinfection agents Methods: This in vitro experimental study tested E.crassipes and P.statoites extracts in combined (EC+PS) forms against several species of bacteria and Candida albicans. The testing of antimicrobial activity using the diffusion method and effectiveness as a disinfectant were tested through the phenol coefficient test. Results: The results of the data analysis of the EC+PS 25%-100% (ratio 1:1) treatment using the ANOVA test and Duncan's posthoc (significance 95%), obtained different inhibition zones for gram-positive, gram-negative bacteria, and C.albicans; EC100%+PS100 extract produced the widest inhibition zone. The inhibitory power of EC+PS extracts ranged from moderate to strong (> 5 mm - > 20 mm). In the phenol coefficient test using a dilution of 1:20-1:250, a good coefficient value (> 1) was obtained from the EC+PS extract treatment and the disinfectant control for all test organisms. Conclusion: E.crassipes and P.stratoites extracts can produce antimicrobial activity with a good phenol coefficient value, which makes their combination a natural disinfectant.

Abstract Background The incidence of foodborne pathogens in ready- to-eat (RTE) can be attributed to various foodborne diseases. Most of the isolated microorganisms from RTE foods are resistant to common antibiotics and thus, resulted to treatment failure when commercially available antibiotics are administered. However, the secondary metabolites secreted by microorganisms can serve as alternative therapy that are reliable and safe. Secondary metabolites obtained from mono- and co-culture microorganisms can inhibit the growth of antibiotic-resistant microorganisms. Bioactive compounds in the secreted metabolites can be identified and utilized as sources of new antibiotics. In this study, antimicrobial activity of secondary metabolites from Lactobacillus fermentum, Saccharomyces cerevisiae, Pleurotus ostreatus, and their co-cultures were tested against foodborne pathogens isolated from RTE foods using agar well diffusion. The bioactive compounds in the metabolites were identified using gas chromatography-mass spectrometry. Results From a total of 100 RTE foods examined, Salmonella enterica, Shigella dysenteriae, Escherichia coli, Klebsiella pneumoniae (subsp ozaenae), Pseudomonas fluorescens, Clostridium perfringes, Bacillus cereus, Listeria monocytogens, and Staphylococcus aureus, Penicillium chrysogenum, Aspergillus flavus, and Aspergillus niger were isolated and displayed multiple antibiotic resistance. The secondary metabolites secreted by co-culture of L. fermentum + P. ostreatus + S. cerevisiae, and co-culture of P. ostreatus + S. cerevisiae have the highest (P ≤ 0.05) zones of inhibition (23.70 mm) and (21.10 mm) against E. coli, respectively. Metabolites from mono-cultured L. fermentum, P. ostreatus, and S. cerevisiae showed zones of inhibition against indicator microorganisms with values ranging from 8.80 to 11.70 mm, 9.00 to 14.30 mm, and 9.30 to 13.00 mm, respectively. Some of the bioactive compounds found in the metabolites of co-cultured microorganisms were alpha-linolenic acid (25.71%), acetic acid 3-methylbutyl ester (13.83%), trans-squalene (12.39%), pentadecylic acid (11.68%), 3- phenyllactic acid (30.13%), linolelaidic acid methyl ester (15.63%), and 4-O-methylmannose (53.74%). Conclusion RTE foods contain multiple antibiotics resistance pathogens. The pronounced antimicrobial activity of the secondary metabolites against microorganisms from RTE foods could be attributed to the presence of bioactive compounds in the metabolites. These metabolites can be exploited as alternative food preservatives, biopharmaceuticals and can be used towards better health delivering systems.

Using probiotics represents a potential solution to post-weaning diarrheal diseases in piglets on commercial farms. The gastrointestinal tract of wild boars serves as a promising reservoir of novel lactic acid bacteria with suitable probiotic characteristics. In this study, we isolated eight bacterial strains from the intestinal content of wild boars identified as representatives of the species Bifidobacterium apri, Lactobacillus amylovorus, and Ligilactobacillus salivarius. These isolates underwent in vitro analysis and characterisation to assess their biological safety and probiotic properties. Analysis of their full genome sequences revealed the absence of horizontally transferrable genes for antibiotic resistance. However, seven out of eight isolates harboured genes encoding various types of bacteriocins in their genomes, and bacteriocin production was further confirmed by mass spectrometry analysis. Most of the tested strains demonstrated the ability to inhibit the growth of selected pathogenic bacteria, produce exopolysaccharides, and stimulate the expression of interleukin-10 in porcine macrophages. These characteristics deem the isolates characterised in this study as potential candidates for use as probiotics for piglets during the post-weaning period.

Metals play vital roles in biological systems, with iron/heme being essential for cellular and metabolic functions necessary for survival and/or virulence in many bacterial pathogens. Given the rise of bacterial resistance to current antibiotics, there is an urgent need for the development of non-toxic and novel antibiotics that do not contribute to resistance to other antibiotics. Gallium, which mimics iron, has emerged as a promising antimicrobial agent, offering a novel approach to combat bacterial infections. Gallium does not have any known functions in biological systems. Gallium exerts its effects primarily by replacing iron in redox enzymes, effectively inhibiting bacterial growth by targeting multiple iron/heme-dependent biological processes and suppressing the development of drug resistance. The aim of this review is to highlight recent findings on the mechanisms of action of gallium and provide further insights into the development of gallium-based compounds. Understanding the mechanisms underlying gallium’s biological activities is crucial for designing drugs that enhance their therapeutic therapies while minimizing side effects, offering promising avenues for the treatment of infectious diseases.

Abstract Panax notoginseng saponins (PNS) are the main active components of Panax notoginseng. But after oral administration, they need to be converted into rare ginsenosides by human gut microbiota and gastric juice before they can be readily absorbed into the bloodstream and exert their effects. The sources of rare ginsenosides are extremely limited in P. notoginseng and other medical plants, which hinders their application in functional foods and drugs. Therefore, the production of rare ginsenosides by the transformation of PNS using Aspergillus fumigatus was studied in this research. During 50 days at 25 ℃ and 150 rpm, A. fumigatus transformed PNS to 14 products (1–14). They were isolated by varied chromatographic methods, such as silica gel column chromatography, Rp-C18 reversed phase column chromatography, semi-preparative HPLC, Sephadex LH-20 gel column chromatography, and elucidated on the basis of their 1H-NMR, 13C-NMR and ESIMS spectroscopic data. Then, the transformed products (1–14) were isolated and identified as Rk3, Rh4, 20 (R)-Rh1, 20 (S)-Protopanaxatriol, C-K, 20 (R)-Rg3, 20 (S)-Rg3, 20 (S)-Rg2, 20 (R)-R2, Rk1, Rg5, 20 (S)-R2, 20 (R)-Rg2, and 20 (S)-I, respectively. In addition, all transformed products (1–14) were tested for their antimicrobial activity. Among them, compounds 5 (C-K) and 7 [20 (S)-Rg3] showed moderate antimicrobial activities against Staphylococcus aureus and Candida albicans with MIC values of 6.25, 1.25 μg/mL and 1.25, 25 μg/mL, respectively. This study lays the foundation for production of rare ginsenosides. Graphical abstract

Abstract Background Several studies have been reported previously on the bioactivities of different extracts of marine molluscs. Therefore, we decided to evaluate the cytotoxic and antimicrobial activities of S. pharaonis ink as a highly populated species in the Red Sea. We extracted the flavonoids from the ink and analyzed their composition. Then we evaluated systematically the cytotoxic and antimicrobial properties of this extract. A pharmacokinetic study was also conducted using SwissADME to assess the potential of the identified flavonoids and phenolic compounds from the ink extract to be orally active drug candidates. Results Cytotoxic activity was evaluated against 5 cell lines (MCF7, Hep G2, A549, and Caco2) at different concentrations (0.4 µg/mL, 1.6 µg/mL, 6.3 µg/mL, 25 µg/mL, 100 µg/mL). The viability of examined cells was reduced by the extract in a concentration-dependent manner. The highest cytotoxic effect of the extract was recorded against A549 and Hep G2 cancer cell lines cells with IC50 = 2.873 and 7.1 µg/mL respectively. The mechanistic analysis by flow cytometry of this extract on cell cycle progression and apoptosis induction indicated that the extract arrests the cell cycle at the S phase in Hep G2 and MCF7, while in A549 cell arrest was recorded at G1 phase. However, it causes G1 and S phase arrest in Caco2 cancer cell line. Our data showed that the extract has significant antimicrobial activity against all tested human microbial pathogens. However, the best inhibitory effect was observed against Candida albicans ATCC 10,221 with a minimum inhibitory concentration (MIC) of 1.95 µg/mL. Pharmacokinetic analysis using SwissADME showed that most flavonoids and phenolics compounds have high drug similarity as they satisfy Lipinski’s criteria and have WLOGP values below 5.88 and TPSA below 131.6 Å2. Conclusion S. pharaonis ink ethanolic extract showed a promising cytotoxic potency against various cell lines and a remarkable antimicrobial action against different pathogenic microbial strains. S. pharaonis ink is a novel source of important flavonoids that could be used in the future in different applications as a naturally safe and feasible alternative of synthetic drugs.

Abstract Mixed ligand complexes of manganese(II), cobalt(II), copper(II), and cadmium(II)with an innovative Schiff base ligand denoted as (L 1 ), 4-(2-((1E,2E)-1-(2-(p-tolyl)hydrazineylidene)propan-2-ylidene)hydrazineyl), served as the principal ligand, while glycine (L2) was employed as secondary ligand were successfully effectively characterized through a comprehensive set of analyses, including Elemental analysis, UV–Visible, FT-IR, Mass spectra, and conductometric measurements. Density functional theory (DFT) computations were executed to discern the enduring electronic arrangement, the energy gap, dipole moment and chemical hardness of the hybrid ligand assemblies. The proposed geometry for the complexes is a distorted octahedral structure. The antimicrobial efficacy of these compounds was assessed against a range of bacterial and fungal strains. Notably, these complexes exhibited promising antimicrobial activities, with the cadmium (II) complex demonstrating superior efficacy towards all tested organisms. These compounds were also examined for their antibiotic properties against H. pylori to explore their broader medical potential. The Schiff base ligand and its corresponding metal complexes displayed substantial potential as an antibiotic against H. pylori. Additionally, the antitumor potential of the synthesized complexes was assessed against MCF-7 (Breast carcinoma) cells—the Cu (II) complex demonstrated superior activity with the lowest IC50 value compared to cisplatin. Moreover, it exhibited reduced cytotoxicity towards normal cells (VERO cells) compared to cisplatin, establishing it as the most potent compound in the study. Furthermore, molecular docking was explored of the Schiff base ligand and its corresponding cadmium(II) complex. The analysis of the docking study yielded valuable structural insights that can be effectively utilized in conducting inhibition studies for example against COVID-19. This comprehensive study highlights these synthesized compounds' multifaceted applications and promising bioactive properties.

Abstract Background cultivated and wild plants are used to treat different ailments. The Astragalus genus is found in temperate and dry climates; thus, it is found in Egypt and the arab world. Astragalus caprinus has a good amount of bioactive chemicals, which may help explain its therapeutic effects in reducing the risk of consequences from disease. Method The phytochemical investigation of the herb and roots of Astragalus caprinus L. included the analytical characterization for the petroleum ether components by GC/MS, unsaponifiable matter (unsap. fraction), and fatty acids (FAME) investigation by GLC analysis. Main flavonoids were chromatographically isolated from ethyl acetate and n-butanol extracts. In vitro antimicrobial activity has been tested against the Gram-positive bacteria Staphylococcus aureus and Streptococcus mutans for different plant extracts, the Gram-negative bacteria Pseudomonas aeruginosa and Klebsiella pneumonia, the fungus Candida albicans and Aspergillus niger, and the Escherichia coli bacterium. Metabolite cytotoxicity was examined using the MTT assay against HepG-2 (human liver carcinoma) and MCF-7 (breast carcinoma). Results Identifying the important components of the herb and root petroleum ether extracts was achieved. Using column chromatography, luteolin, cosmosiin (apigenin-7-O-glucoside), and cynaroside (luteolin-7-O-glucoside) were separated and identified using UV, NMR, and Mass Spectroscopy. Root extracts displayed potential antimicrobial activity against most of the tested pathogens. Both extracts (herb and roots) were active against the MCF-7 cell line and HepG-2 cell line with IC50 62.5 ± 0.64 and 72.4 ± 2.3 µg/ml, and 75.9 ± 2.5 and 96.8 ± 4.2 µg/ml, respectively. Conclusion Astragalus caprinus seems to be a promising source of bioactive compounds that could potentially aid in preventing disease complications and address common health issues in developing countries. Moreover, the various parts of this plant could be utilized as natural raw materials for producing health-boosting products that could address common health issues in developing countries.

Edible seaweed - Caulerpa lentillifera is being cultivated along the coast of Khanh Hoa province, Vietnam, and makes a relatively large contribution to the economic development of this region. Bacterial strains originating from marine sources such as those associated with seaweed and hard coral were screened for properties of promote plant growth with the capacity of indole-3-acetic acid (IAA) - a phytohormone belonging to auxin group, the phosphate solubilization ability and antibacterial activity of IAA-producing strains were also performed in this study. Robust strains were identified by morphological methods with biochemical tests and analysis of 16s RNA sequences. Isolate RN06 produced high amounts of IAA, utilized inorganic phosphate, and inhibited Bacillus subtilis ATCC6633, Escherichia coli 0157, and Serratia marcescens PDL100. The IAA producer HRA5 isolated from hard coral demonstrated the ability to solubilize phosphate and exhibited antibacterial activity against B. subtilis. Morphological analysis and 16sRNA sequencing showed that isolate RN06 was the closest strain to Bacillus amyloliquefaciens and HRA5 was linked to Pseudomonas sp. This is the first report of isolated bacteria from seaweed and corals from the Vietnamese sea served as potential strains for further research of the application of biological inoculants specifically for seaweed farming.

Chronic infections often involve notorious pathogens like Pseudomonas aeruginosa and Staphylococcus aureus, demanding innovative antimicrobial strategies due to escalating resistance. This investigation scrutinized the antibacterial prowess of bile salts, notably taurocholic acid (TCA), ursodeoxycholic acid (UDCA), and ox bile salt (OBS), against these pathogens. Evaluations encompassed minimum inhibitory concentration (MIC) determination, scrutiny of their impact on biofilm formation, and anti-virulence mechanisms. UDCA exhibited the highest efficacy, suppressing S. aureus and P. aeruginosa biofilms by 83.5% and 78%, respectively, at peak concentration. TCA also significantly reduced biofilm development by 81% for S. aureus and 75% for P. aeruginosa. Microscopic analysis revealed substantial disruption of biofilm architecture by UDCA and TCA. Conversely, OBS demonstrated ineffectiveness against both pathogens. Mechanistic assays elucidated UDCA and TCA’s detrimental impact on the cell membrane, prompting the release of macromolecular compounds. Additionally, UDCA and TCA inhibited protease and elastase synthesis in P. aeruginosa and staphyloxanthin and lipase production in S. aureus. These results underscore the potential of UDCA and TCA in impeding biofilm formation and mitigating the pathogenicity of S. aureus and P. aeruginosa.

The emergence of antibiotic-resistant pathogens in clinical settings has intensified the search for new probiotic strains with both health benefits and technological utility. This study aims to identify and characterize promising antimicrobial cultures derived from milk and dairy products, capable of inhibiting opportunistic pathogens. The samples of dairy products were collected from various markets across Kazakhstan. Microorganisms isolated from these samples underwent identification through 16S rRNA and ITS gene sequencing, using the BLAST algorithm. Their antimicrobial activity was assessed using the delayed antagonism method against pathogenic microorganisms including E. coli, S. aureus, Pseudomonas sp., Candida sp., and B. subtilis. Additionally, the isolates were evaluated for resistance to environmental stress factors such as temperature, pH, salt, ethanol, glucose, and peroxide. From 24 distinct samples, 33 isolates were purified, with 15 demonstrating high viability (108–109 CFU/mL) and stress resistance. Notably, Lacticaseibacillus casei AK and Enterococcus faecium KS exhibited resistance to all tested stress conditions. Antimicrobial screening revealed strong activity by strains LP, LB, and S-2 against multiple pathogens. Genotyping and carbohydrate fermentation tests identified these effective isolates as belonging to the genera Lactobacillus, Lactococcus, Enterococcus, Lactiplantibacillus, Streptococcus, and the yeast genus Pichia. This study underscores the industrial and health potential of the identified microorganisms. Prominent among the strains, Lactiplantibacillus pentosus LP, Lacticaseibacillus casei AK, Lactiplantibacillus argentoratensis LB, Lactiplantibacillus plantarum S-2, and Enterococcus faecium KS have been recognized as potent probiotics. These strains exhibit broad-spectrum antimicrobial activity coupled with robust stress tolerance, making them suitable candidates for probiotic applications.

Diabetic patients with poor blood glucose control are highly susceptible to developing secondary infections, which can lead to the development of prolonged diabetic ulcers. Therefore, a suitable medication that may effectively prevent the occurrence of secondary infections is crucial to shorten the closure of diabetic ulcers. Red betel leaf (Piper crocatum Ruiz & Pav) is reported to possess antimicrobial activity due to the presence of flavonoids. This study aimed to evaluate the effect of ethanolic extract of red betel leaf (EERBL) ointments against the most prevalent bacteria associated with diabetic foot ulcers (DFU): Staphylococcus aureus and Pseudomonas aeruginosa. The EERBL was prepared by macerating powdered red betel leaf with 96% ethanol and was screened for the presence of flavonoids and the determination of total flavonoid content (TFC) by thin layer chromatography and UV-Vis spectrophotometry, respectively. This study examined three hydrophilicbased ointments containing 10%, 20%, and 30% EERBL, respectively, followed by characterization for pH, spreadability, adhesivity, and viscosity. The EERBL ointments' effect on the bacteria was evaluated using the well-diffusion method by observing inhibition zone formation after 24-hour incubation. The results showed that varying the EERBL concentrations in the formulations led to different spreadability, adhesivity and viscosity (p

Objective(s): The purpose of this study was to synthesize copper oxide nanoparticles (CuO NPs), cobalt oxide nanoparticles (Co3O4 NPs), and CuO-Co3O4 nano system using Moringa stenopetala plant leaf extract. These nanoparticles were specifically developed for their antioxidant and antibacterial properties.Materials and Methods: The nanoparticles were synthesized by a green synthesis approach using M. stenopetala leaf extract. Comprehensive characterization using spectroscopic techniques such as X-ray diffraction (XRD), UV-visible spectroscopy, scanning electron microscopy (SEM), Fourier transform infrared (FT-IR), and thermogravimetric analysis (TGA) was executed.Results: UV-Vis analysis revealed an energy bandgap of 3.32 eV for CuO NPs, 3.36 eV for Co3O4 NPs, and 3.66 eV for CuO-Co3O4 nano system. XRD analysis revealed that CuO NPs have a monoclinic crystal structure with an average crystallite size of 11.59 nm, whereas Co3O4 NPs have a cubic crystal structure with an average crystallite size of 12.25 nm. The CuO-Co3O4 nano system exhibited an average crystal size of 9.53 nm. The SEM images showed inhomogeneous composition and large granular particles of CuO NPs, inhomogeneous cubic shape and size with encapsulation and hydrogen bonding aggregation of Co3O4 NPs, and particle heterogeneity. The CuO-Co3O4 nano system. FT-IR analysis confirmed the presence of bioactive molecules such as flavonoids, tannins, terpenoids, steroids, glycosides, saponins, and phenols that actively participate in the synthesis process.Conclusion: The synthesized CuO-Co3O4 nano system showed superior inhibitory effects against the selected bacterial strains compared to CuO NPs and Co3O4 NPs. Furthermore, they showed excellent antioxidant activity. These results highlight the significant potential of CuO-Co3O4 nano system for a wide range of applications due to their remarkable bacterial inhibition and radical scavenging properties.

Abstract Clothing and textile industries are major contributors to environmental pollution including textile manufacturing through garment production, spinning, weaving, and dyeing. In this context, the sustainability textile industry is a big challenge and contributes to serving a large segment of society. Also, textile wastes could be used as a raw material for added-value products. Herein, in this study, recycling of residues fabric was treated with antimicrobial nanocomposite to reach the best use of exhausts and obtain multifunction products of aesthetic via the technical design of the waste raw materials. Besides, solving the unemployment problem by opening fields for small industry projects capable of producing high-value textile artifacts, especially when treated against microbes, can be applied to home furnishings. The waste fabric was treated via green synthesis nanocomposite based on chitosan and in situ prepared ZnONPs and cross-linked with tannic acid. The prepared nanocomposite was characterized using physicochemical analysis including attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD). Additionally, the nanocomposite and treated fabric topographical behavior were studied using scanning electron microscopy (SEM) attachment with energy dispersive X-ray analysis (EDX), and images were processed to evaluate the roughness structure. Additionally, high-resolution transmission electron microscopy (HR-TEM) and dynamic light scattering (DLS) were performed to ensure the size and stability of the nanocomposite. The obtained results affirmed the green synthesis of nanocomposite with a size around 130 nm, as well as the doped ZnONPs average size of 26 nm and treated waste fabric, performed a promising attraction between nanocomposite and fabric fibers. Moreover, the antimicrobial study observed excellent activity of nanocomposite against bacteria and unicellular fungi as well.

Abstract Essential oils (EOs) represent a pivotal source for developing potent antimicrobial drugs. However, EOs have seldom found their way to the pharmaceutical market due to their instability and low bioavailability. Nanoencapsulation is an auspicious strategy that may circumvent these limitations. In the current study, lemongrass essential oil (LGO) was encapsulated in zein-sodium caseinate nanoparticles (Z-NaCAS NPs). The fabricated nanocomposite was characterized using dynamic light scattering, Fourier-transform infrared spectroscopy, differential scanning calorimetry, and transmission electron microscopy. The antimicrobial activity of LGO loaded NPs was assessed in comparison to free LGO against Staphylococcus epidermidis, Enterococcus faecalis, Escherichia coli, and Klebsiella pneumoniae. Furthermore, their antibacterial mechanism was examined by alkaline phosphatase, lactate dehydrogenase, bacterial DNA and protein assays, and scanning electron microscopy. Results confirmed the successful encapsulation of LGO with particle size of 243 nm, zeta potential of – 32 mV, and encapsulation efficiency of 84.7%. Additionally, the encapsulated LGO showed an enhanced thermal stability and a sustained release pattern. Furthermore, LGO loaded NPs exhibited substantial antibacterial activity, with a significant 2 to 4 fold increase in cell wall permeability and intracellular enzymes leakage versus free LGO. Accordingly, nanoencapsulation in Z-NaCAS NPs improved LGO physicochemical and antimicrobial properties, expanding their scope of pharmaceutical applications.