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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.

Abstract The growth of material science and technology places high importance on creating better processes for synthesizing copper nanoparticles. Thus, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using Priestia sp. bacteria utilizing a variety of low-cost agro-industrial wastes and byproducts. The biosynthesis of CuNPs was conducted using glucose medium and copper ions salt solution, then it was replaced by utilizing low-cost agro-industrial wastes. UV–visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), High-resolution transmission electron microscope (HR-TEM), Attenuated Total Reflectance and Fourier transform infrared (ATR-FTIR), and zeta potential were used to characterize the biosynthesized CuNPs. The cytotoxicity of CuNPs using Vero -CCL-81 cell lines, and antibacterial and antitumor properties using human colon epithelial colorectal adenocarcinoma Caco-2-HTB-37 cell lines were assessed. The UV–visible and DLS studies revealed CuNPs formation, with a maximum concentration of 6.19 ppm after 48 h, as indicated by a 0.58 Surface plasmon resonance (SPR) within 450 nm and 57.73 nm particle size. The 16S rRNA gene analysis revealed that Priestia sp. isolate is closely related to Priestia megaterium and has been deposited in the NCBI GenBank with accession number AMD 2024. The biosynthesis with various agro-industrial wastes indicated blackstrap sugar cane molasses being the most effective for reducing CuNPs size to 3.12 nm owing to various reducing and stabilizing active compounds. The CuNPs were free of contaminants, with a sphere-shaped structure and a cytotoxicity assessment with an IC50 of 367.27 μg/mL. The antibacterial activity exhibited by the most susceptible bacteria were Bacillus cereus ATCC 11788 and Staphylococcus aureus ATCC 6538 with inhibition zones of 26.0 mm and 28.0 mm, respectively. The antitumor effect showed an IC50 dose of 175.36 μg/mL. Based on the findings, the current work sought to lower product costs and provide a practical solution to the environmental contamination issues brought on by the buildup of agricultural wastes. In addition, the obtained CuNPs could be applied in many fields such as pharmaceuticals, water purification, and agricultural applications as future aspects.

Abstract Phoenix dactylifera L. and its wastes are known to be high in nutrients that are beneficial to human health. The study aimed to evaluate the antimicrobial, antibiofilm, and antiviral properties of Phoenix dactylifera L. pits extract (PDPE) in vitro. Gas chromatography-mass spectrometry (GC–MS) analysis indicated phenol, 2,5-bis(1,1-dimethyl ethyl), tetradecanoic acid, octaethylene glycol monododecyl ether, á-D-glucopyranosiduronic acid, and heptaethylene glycol monododecyl ether existence. The PDPE influenced pathogenic microorganisms, with inhibition zone diameters (IZDs) ranging from 10.0 to 35.0 mm. Staphylococcus aureus ATCC 5638 had the highest IZD, while Salmonella typhi DSM 17058 and Shigella sonnei DSM 5570 had the lowest. The antifungal effect observed only in spore failure or conidia formation. PDPE showed a 100% antibacterial spectrum against bacteria, with MIC values between 250 and 1000 µg/ml. MIC was only indicated with S. aureus of 500 µg/ml. MBC values ranged from 500 to 1000 g/ml, with MBC values of 500 g/ml for B. cereus, E. faecalis, S. typhi, and S. sonnei. The activity was 66.7% at 500 µg/ml, further concentrations of 125–250 g/ml had no antibacterial effect. PDPE biofilm inhibition % had the highest percentage of inhibition (98.59%) with S. aureus, B. cereus (94.12%), and E. coli (74.46%). With 50% (CC50) viral activity, the highest non-toxic PDPE dose was found to be at 123.0 µg/ml.

Abstract The growth of material science and technology places a high importance on the creation of better processes for the synthesis of copper nanoparticles. So that, an easy, ecological, and benign process for producing copper nanoparticles (CuNPs) has been developed using candy leaf (Stevia rebaudiana) leaves aqueous extract for the first time. UV-visible spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), high-resolution transmission electron microscope (HR-TEM), Fourier transmission infrared (FTIR), and zeta potential were applied to demonstrate strong characterization for the biosynthesized stevia-CuNPs. The UV-visible absorbance at 575 nm of surface plasmon resonance (SPR) was 1.2. The particle size mean diameter was recorded as 362.3 nm with − 10.8 mV zeta potential. The HR-TEM scanning revealed 51.46–53.17 nm and spherical-shaped stevia-CuNPs surrounded by coat-shell proteins. The cytotoxicity and cytocompatibility activity assay revealed that stevia-CuNPs was safe in lower concentrations and had a significant cell viability reduction in higher concentrations. The produced stevia-CuNPs were applied as antimicrobial agents against eight pathogenic bacteria and five fungi strains. The inhibitory action of the stevia-CuNPs was more pronounced in bacteria than in fungi, and they likewise demonstrated further inhibition zones in Staphylococcus aureus (50.0 mm) than in Aspergillus flavus (55.0 mm). With inhibition zone sizes of 50.0 mm and 47.0 mm and 50 µg/ml minimum inhibitory concentration, S. aureus and A. flavus were the most inhibited pathogens. The minimum lethal effect (MLC) estimate for S. aureus was 50 µg/ml, whereas 75 µg/ml for A. flavus. The stevia-CuNPs mode of action was characterized as bactericidal/fungicidal as the ratio of MIC to MLC was estimated to be equal to or less than 2. After all, stevia-CuNPs could be used as an alternative to commercial antibiotics to solve the problem of multidrug-resistant (MDR) microorganisms.

Abstract The current study aimed to find an effective, simple, ecological, and nontoxic method for bacterial green synthesis of zinc oxide nanoparticles (ZnONPs) using the bacterial strain Priestia megaterium BASMA 2022 (OP572246). The biosynthesis was confirmed by the change in color of the cell-free supernatant added to the zinc nitrate from yellow to pale brown. The Priestia megaterium zinc oxide nanoparticles (Pm/ZnONPs) were characterized using UV–Vis spectroscopy, high-resolution transmission electron microscopy (HR-TEM), energy-dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR), and zeta potential. The Pm/ZnONPs characterization showed that they have a size ranging between 5.77 and 13.9 nm with a semi-sphere shape that is coated with a protein-carbohydrate complex. An EDX analysis of the Pm/ZnONPs revealed the presence of the shield matrix, which was composed of carbon, nitrogen, oxygen, chlorine, potassium, sodium, aluminum, sulfur, and zinc. The results of the FTIR analysis showed that the reduction and stabilization of the zinc salt solution were caused by the presence of O–H alcohols and phenols, O=C=O stretching of carbon dioxide, N=C=S stretching of isothiocyanate, and N–H bending of amine functional groups. The produced ZnONPs had good stability with a charge of − 16.2 mV, as evidenced by zeta potential analysis. The MTT assay revealed IC50 values of 8.42% and 200%, respectively, for the human A375 skin melanoma and human bone marrow 2M-302 cell lines. These findings revealed that the obtained Pm/ZnONPs have the biocompatibility to be applied in the pharmaceutical and biomedical sectors.

Abstract Mosquitoes prefer stagnant areas near hospitals to live and easily spread pathogenic bacteria. Our current study aims to isolate multidrug-resistant (MDR) Staphylococcus aureus isolates from midguts of Mosquito Culex pipiens and study the potential of mint as a biocontrol strategy against C. pipiens larvae and their midgut-borne S. aureus. Samples of the third and fourth larval instars of C. pipiens were collected from water ponds around three Cairo hospitals. Ciprofloxacin, gentamycin and tetracycline, as well as various concentrations of mint leaf extract (MLE) were tested for antibiotic susceptibility. Sixty-five isolates were obtained and showed antibiotic resistance to tetracycline, gentamycin, ciprofloxacin, and undiluted MLE with resistant percentages (%) of 27.69, 30.76, 17.46, and 23.08%, respectively. Undiluted MLE inhibited 61.53% of the multidrug S. aureus isolates, whereas it couldn't inhibit any of these isolates at dilutions less than 50 μg/mL. The MIC of MLE was ≤ 700 µg/mL, while the MIC of the antibiotics ranged from 0.25 to 5.0 µg/mL for the three antibiotics. The most inhibited S. aureus isolate was identified by 16SrRNA sequencing approach and registered in GenBank as S. aureus MICBURN with gene accession number OQ766965. MLE killed all larval stages after 72 h of exposure, with mortality (%) reaching 93.33 and 100% causing external hair loss, breakage of the outer cuticle epithelial layer of the abdomen, and larvae shrinkage. Histopathology of treated larvae showed destruction of all midgut cells and organelles. Gas chromatography (GC) of MLE revealed that menthol extract (35.92%) was the largest active ingredient, followed by menthone (19.85%), D-Carvone (15.46%), Pulegone (5.0579%). Docking analysis confirmed that alpha guanine and cadinol had the highest binding affinity to both predicted active sites of Culex pipiens acetylcholinesterase. As a result, alpha-guanine and cadinol might have a role as acetylcholinesterase inhibitors.

Abstract Polyphenolics have been predicted to effectively develop antimicrobial agents for the food industry as food additives and promote human health. This study aims to synthesize pomegranate peel extract (PPE) with silver nanoparticles (AgNPs) against eight foodborne pathogens. Multispectroscopic analysis of UV–vis spectroscopy, Zeta potential, Fourier transform infrared (FTIR) and scanning electron microscopy (SEM) analysis were used to characterize the interaction between PPE and AgNPs. Eight foodborne pathogenic strains (six bacterial and two fungal strains) Bacillus subtilis ATCC 6633, Enterococcus faecalis ATCC 29212, Escherichia coli ATCC 8379, Klebsiella pneumoniae ATCC 00607, Salmonella typhi DSM 17058, Shigella sonnei DSM 5570, Aspergillus flavus ATCC 9643, and Rhizopus oryzae ATCC 96382 were used to test the inhibitory potential of PPW-AgNPs. The reaction colour of PPE-AgNPs from yellow to brown indicated that the nanoparticles were successfully formed. The UV absorption of PPE-AgNPs was detected at 440 nm of 0.9 SPR. SEM image of PPE-AgNPs exhibited spherical shapes with a zeta potential of − 20.1 mV. PPE-AgNPs showed high antimicrobial activity against all tested strains. The highest inhibition activity of PPE-AgNPs was recorded for the B. subtilis strain followed by K. pneumonia, while the highest resistance was noticed for R. oryzae. The components of pomegranate peel were analyzed using gas chromatography–mass spectrometry (GC–MS). The major constituents of pomegranate peel is phenol (51.1%), followed by Isocitronellol (19.41%) and 1-Propanol, 2-(2-hydroxypropyl)- (16.05%). PPE is key in the simple, eco-friendly green synthesis of extracellular stable AgNPs as an alternative source for harmful chemical disinfectants.

Abstract Food waste is a major issue, with one-third of food wasted yearly. This study aimed to produce sustainably the industrial enzyme alpha-amylase using discarded bread waste. Brown (BBW) and white bread waste (WBW) were tested as growth substrates using solid-state and submerged fermentation. The biosynthesized α- amylase is applied to treat starch-heavy industrial wastewater and for textile desizing. Bacillus amyloliquefaciens showed the highest starch hydrolysis and enzyme activity on solid and liquid media. α-amylase production by B. amyloliquefaciens was optimized via a one-factor-at-a-time evaluation of production parameters. Optimal production occurred by submerged fermentation of BBW inoculated with 2% B. amyloliquefaciens at 37 °C and 200rpm for 24 h, reaching 695.2 U/mL α- amylase. The crude enzyme was immobilized on calcium alginate beads with 96.6% efficiency and kept 88.5% activity after 20 reuses, enhancing stability. A Box–Behnken design (BOX) assessed variable interactions. Response surface methodology (RSM) generated a quadratic model and analysis of variance (ANOVA analysis) fitting experimental starch hydrolysis data. Optimal conditions were pH 9, 45 °C, 70% starch, and 27.5 U/mL enzyme incubated for 15 min of contact time, with a high R2 of 0.83. ANOVA confirmed the enzyme's alkaliphilic and thermophilic nature. Using enzyme concentrations ranging from 10.9 to 695.1 U/mL, the enzyme desized textiles in 15 min at pH 9.0 and 45 °C with 96.3% efficiency. Overall, the optimized α- amylase from bread waste has industrial potential for sustainable starch processing.

Abstract Bioconversion using fungi, as natural factory of many applicable bioactive compounds, as enzymes utilizing agro-residue substrates as a solid, abundant, low-cost growth and enzyme production media. This study characterized and applied a tannase enzyme (308 U/mg) from Aspergillus niger A8 + Trichoderma viride co-cultures utilizing pomegranate peels. The partially purified enzyme showed maximal relative activity at 37–65 °C for 10 min and kinetics of thermal inactivation energy at a high point at 60 °C for 0.040/min. The half-life was 37 °C for 58.6 min, temperature coefficient Q10 of tannase was maximal for 1.38 between 40 and 50 °C, and the activation energy was 17.42 kJ/mol. The enzyme activity peaked in the pH range of 4–8, and the maximum relative activity (100.6%) for tannase was achieved at pH 6. The Km and Vmax values for purified enzymes using tannic acid were 7.3 mg/mL and 3333.33 U/mL, respectively. The enzyme reduced the total tannin content in all tannin-rich substrates after 12h. The gallic acid (GA) had total phenols of 77.75 ppm and antioxidant activity of 82.91%. It was observed that the GA as antimicrobial influencer exhibited the largest inhibitory zone diameter (IZD) of 31 ± 1.0 mm against Pseudomonas aeruginosa ATCC27853. The GA minimum inhibitory concentration value was ranged from 7770.0–121.41 µg/mL. The obtained GA showed a bactericidal effect against all bacterial strains except Shigella sonnei DSM5570 and Salmonella typhi DSM17058, which showed bacteriostatic behavior.

Abstract Mosquito control in Egypt depends on applying chemical synthetic pesticides that impact negatively on human health and the environment as well as the development of antibiotic and chemical resistance. This study aims to control the 3rd and 4th instars of Culex pipiens larvae using four bacterial strains. According to Phenotypic and molecular identification, the four isolates were identified as Bacillus subtilis MICUL D2023, Serratia marcescens MICUL A2023, Streptomyces albus LARVICID, and Pseudomonas fluorescens MICUL B2023. All strains were deposited in GenBank under accession numbers OQ764791, OQ729954, OQ726575, and OQ891356, respectively. Larvicidal activity of all microbial strain metabolites against a field strain of C. pipiens explored low LC50 results and reached its lowest values on the 3rd day with values of 6.40%, 38.4%, and 46.33% for P. fluorescens, S. albus, and S. marcescens, respectively. In addition, metabolites of P. fluorescence were more toxic than those of S. albus, followed by S. marcescens. B. subtilis shows no larvicidal effect on both field and lab mosquito strains. Microscopic alterations of 3rd and 4th instars showed toxic effects on different body parts (thorax, midgut, and anal gills), including losing external hairs, abdominal breakage, and larvae shrinkage, as well as different histological malformations in the digestive tract, midgut, and cortex. GC–MS analysis detected 51, 30, and 32 different active compounds from S. albus, S. marcescens, and P. fluorescens, respectively. GC detected 1, 2-BENZEA2:A52NEDICARBOXYLIC ACID, 2-Cyclohexene-1-carboxylic-acid-5-2-butenyl-methyl ester, and 3 octadecahydro2R3S4Z9Z-11R-12S from S. albus, S. marcesens, and P. fluorescens, respectively. Total protein, Total carbohydrate, and Acetylcholine esterase activity indicated significantly low levels on the 3rd day. All strain metabolites were safe against HSF cell lines. The docking results confirmed the role of the produced metabolites as larvicidal agents and Acetylcholine esterase inhibition. Such a problem need more studies on applying more and more natural pesticides.

Abstract The emergence of antimicrobial resistance in foodborne bacterial pathogens has raised significant concerns in the food industry. This study explores the antimicrobial potential of biosynthesized silver nanoparticles (AgNPs) derived from Agaricus bisporus (Mushroom) against foodborne bacterial pathogens. The biosynthesized AgNPs were characterized using various techniques, including UV–visible spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy, high-resolution scanning electron microscopy with energy dispersive X-ray spectroscopy, dynamic light scattering, and zeta potential analysis. The antibacterial activity of the AgNPs was tested against a panel of foodborne bacterial strains, and their cytotoxicity was evaluated on normal human skin fibroblasts. Among the tested strains, Pseudomonas aeruginosa ATCC 27853 showed the highest sensitivity with an inhibition zone diameter (IZD) of 48 mm, while Klebsiella quasipneumoniae ATTC 700603 and Bacillus cereus ATCC 11778 displayed the highest resistance with IZDs of 20 mm. The silver cations released by AgNPs demonstrated strong bactericidal effects against both Gram-positive (G + ve) and Gram-negative (G − ve) bacteria, as evidenced by the minimum inhibitory concentration/minimum bactericidal concentration (MBC/MIC) ratio. Moreover, cytotoxicity testing on normal human skin fibroblasts (HSF) indicated that AgNPs derived from the mushroom extract were safe, with a cell viability of 98.2%. Therefore, AgNPs hold promise as an alternative means to inhibit biofilm formation in the food industry sector.

Abstract Despite their threatens for Egyptian stone monuments, A few studies focused on using biocontrol agents against deteriorative fungi and bacteria instead of using chemical assays that leave residuals leading to human toxicity and environmental pollution. This work aims to isolate and identify fungal and bacterial isolates that showed deteriorative activities from stone monuments in Temple of Hathor, Luxor, Egypt, as well as determine the inhibitory activity of metabolites produced by Streptomyces exfoliatus SAMAH 2021 against the identified deteriorative fungal and bacterial strains. Moreover, studying the spectral analysis, toxicological assessment of metabolites produced by S. exfoliatus SAMAH 2021 against health human cell fibroblast, and colorimetric measurements on the selected stone monuments. Ten samples were collected from Temple of Hathor, Luxor, Egypt. Three fungal isolates and one bacterial isolate were obtained and identified as A. niger isolate Hathor 2, C. fioriniae strain Hathor 3, P. chrysogenum strain HATHOR 1, and L. sphaericus strain Hathor 4, respectively. Inhibitory potential of the metabolites in all concentrations used (100–25%) against the recommended antibiotics (Tetracycline 10 µg/ml and Doxycycline (30 µg/ml) showed an inhibitory effect toward all tested deteriorative pathogens with a minimum inhibition concentration (MIC) of 25%. Cytotoxicity test confirmed that microbial filtrate as the antimicrobial agent was safe for healthy human skin fibroblast with IC50 of

This study aimed to focus on the Nile's raw water purification and sanitation in the Warraq al Hadar area, Egypt, using Moringa oleifera leaf powder. The water turbidity, pH, and total fecal-coliforms were assessed. The water turbidity and pH were decreased on addition of M. oleifera leaf powder at 2, 4, 6, 8, and 10 µg\ ml; with reductions of 49.8, 68.7, 87.4, 92.0, and 93.7 % for turbidity, while the pH was reduced by 12.37, 20.0, 28.14, 38.14, and 38.14%, respectively. Using the most probable number approach (MPN), the highest decrease in the coliform bacterial count was observed at 10 µg\ ml of MOL recording 60 cfu\ 100 ml. On estimating the in vitro inhibitory effect of M. oleifera leaf powder on the fecal-coliform bacterial strains using the agar well diffusion assay, Escherichia coli ATCC 8739 was the most affected strain, recording an inhibition zone diameter of 37.0 mm, while Salmonella typhi DSM 17058 was the least inhibited strain with an IZD of 30.0 mm. The minimum inhibitory concentration (MIC) of M. oleifera leaf powder was 6.25 µg\ ml for E. coli, Shigella sonnei DSM 5570, and S. typhi DSM 17058, while it was 12.5 µg\ ml for Enterococcus faecalis ATCC 7080. The minimum bactericidal concentration (MBC) of the M. oleifera leaf powder was equivalent to 25.0 µg\ ml for Enterococcus faecalis, 12.50 µg\ ml for S. typhi, and 6.25 µg/ ml for E. coli and Shigella sonnei. Biocompatibility of the M. oleifera leaf powder was confirmed using the oral epithelial cell lines (OEC), which recorded an IC50 of 716.1 μg\ ml, whereas cell viability of 100.0, 94.1, 90.5, and 88.0 % was observed on application of the MOL powder at different doses of 25, 50, 100, and 150 μg\ ml, respectively.

Spherical homogeneous 32 nm, protein coated Pseudomonas silesiensis strain A3 CuNPs was investigated for their cytotoxicity effect as well as antimicrobial and antitumor activity. CuNPs cytotoxicity was estimated using human normal lung cell lines (Wi38) against CuNPs with concentrations ranging from 25 to 150 μg/mL using neutral red uptake assay. The cytotoxicity study revealed that the bacterial CuNPs had an impact on Wi38 cell viability at concentrations of 25, 50, 100 and 150 μg/mL CuNPs were 95.8, 91.1, 89.2 and 82.3%, respectively, with a strong correlation coefficient (r = 0.94) and a CuNPs IC50 value of 1057.0 μg/mL. CuNPs exhibit a broad-spectrum antimicrobial activity against various microorganism species, including fungi and Gram positive and negative bacteria using the agar-well diffusion method. The findings revealed that the most sensitive pathogens were Staphylococcus aureus ATCC5638 and Aspergillus flavus ATCC 9643 which tended to have a high inhibition zone diameter (50 and 47 mm, respectively). The minimum inhibitory concentration (MIC) of CuNPs was 50 μg/mL. The minimum lethal concentration (MLC) values were 50 and 75 μg/mL for S. aureus ATCC 5638 and A. flavus ATCC 9643, respectively. MLC/MIC ratio was ≤2, suggesting the CuNPs had a bactericidal or fungicidal effect on both pathogenic strains. Results also indicated that bacterial CuNPs at varying concentrations of 25, 50, 100 and 150 μg/mL were such a good antitumor agent against A549 lung carcinoma cell lines with an IC50 value of 137.5 μg/mL and a cell viability of 89.3, 79.6, 64.9 and 44.1%, respectively. The results also suggested that the biosynthesized-CuNPs were an antimicrobial and anticancer agent that could be used in future in food preservation, biomedicine and pharmaceutical fields.