Shigella Dysenteriae Research Articles

Antibacterial Potential of Ethanol Extract from White Pidada (Sonneratia alba) Leaves Against Gastrointestinal Pathogens

The antibacterial properties of the ethanol extract of White Pidada leaves (Sonneratia alba), a mangrove plant rich in bioactive compounds such as phenols, flavonoids, steroids, saponins, triterpenoids, tannins, and alkaloids, were evaluated in this study. The research focused on determining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) against gastrointestinal infection-causing bacteria, including Salmonella typhii, Shigella dysenteriae, Escherichia coli, and Vibrio cholerae. The MIC results showed effective inhibition at concentrations as low as 0.025% for Shigella dysenteriae, 0.05% for Salmonella typhii and Vibrio cholerae, and 0.5% for Escherichia coli. The MBC analysis indicated bactericidal activity at higher concentrations, with significant effects observed at 1% for Salmonella typhii, 0.05% for Shigella dysenteriae and Vibrio cholerae, and 0.1% for Escherichia coli. Agar diffusion tests confirmed that increasing extract concentrations correlated positively with the inhibition zone diameter, highlighting the potential of White Pidada leaves as a natural antibacterial agent.

Antibacterial Activity of Endophytic Fungi Isolated from Parang Romang (Boehmeria virgata (G.Forst) Guill) Leaves Against Gastrointestinal Pathogens

Parang romang (Boehmeria virgata (G.Forst) Guill) is a plant traditionally used for treating various digestive tract infections. However, obtaining bioactive compounds directly from the plant requires significant biomass. Therefore, endophytic fungi, sourced from specific plant parts, are explored for their ability to produce similar bioactive compounds. The research examined the potential antibacterial activity of endophytic fungi isolated from parang romang leaves against common gastrointestinal pathogens. The methods used in was, characterization of endophytic fungal isolates, and antagonistic activity was evaluated using the agar diffusion method. The results showed that the endophytic fungal strains, namely isolates IFBV 6, IFBV 7, and IFBV 10 could inhibit the bacteria Escherichia coli, Salmonella typhi, Shigella dysenteriae, and Vibrio cholera. With an average zone of inhibition for each strains isolate against Esherichia coli respectively 11.53 mm, 10.49 mm, and 14.85 mm; Salmonella typhi 14.47 mm, 8.66 mm, and 15.51 mm; Shigella dysenteriae 22.28 mm, 13.76 mm, and 15.33 mm; and Vibrio cholera 16.91mm, 11.94mm, 15.16mm. In conclusion, isolated endophytic fungal strains hold promise as potential as antibacterialn agents.

Antibacterial Properties in Fermentate Extracts of Endophytic Fungus Derived from Marine Algae Caulerpa lentillifera Against Gastrointestinal Pathogenic Bacteria

Endophytic fungi, residing symbiotically within living plant tissues, are a promising source of novel bioactive compounds. These fungi are known to produce secondary metabolites with a wide range of biological activities, including antibacterial properties. This study explored the antibacterial potential of fermented extracts from endophytic fungi isolated from the marine alga Caulerpa lentillifera, a food source consumed by coastal communities and traditionally used for medicinal purposes. Thin-layer chromatography (TLC) bioautography was employed to identify extracts with activity against common gastrointestinal pathogenic bacteria, such as Escherichia coli, Shigella dysenteriae, and Salmonella typhi. Two endophytic fungal isolates displayed promising antibacterial activity against these pathogens. TLC analysis tentatively identified the presence of flavonoids and alkaloids, potentially responsible for the observed effects. This research sheds light on the pharmacological potential of endophytic fungi and their applications in combating bacterial infections.

Antibacterial Activity in Ethanol Extract of Kersen Flowers (Muntingia calabura L.) Against Bacteria Causing Gastrointestinal Tract Infections Using the Agar Diffusion Method

The increasing prevalence of antibiotic resistance necessitates the exploration of alternative treatments such as medicinal plants. This study evaluates the antibacterial potential of Kersen flowers (Muntingia calabura L.) against pathogens causing gastrointestinal infections. Aimed at determining the antibacterial effectiveness of ethanol extracts from Kersen flowers, the research tests the activity against Escherichia coli, Salmonella typhi, Vibrio cholerae, and Shigella dysenteriae. Employing the agar diffusion method, various concentrations of the extract (0.05% to 10%) were analyzed. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were also assessed to identify the lowest effective concentrations. The ethanol extract demonstrated significant antibacterial activity; notably, the largest inhibition zone measured 30.74 mm at a concentration of 10%. Effective MICs were as low as 0.1% for all tested bacteria, while MBCs ranged from 0.1% to 0.4%. These results suggest that ethanol extracts of Kersen flowers exhibit potent antibacterial properties against major gastrointestinal pathogens, supporting further exploration of these extracts as a natural antibacterial treatment and offering a potential alternative to conventional antibiotics.

Gb3 trisaccharide-bearing exosomes as a novel neutralizer for Shiga toxin type 1

Shiga toxin types 1 (Stx1) and 2 (Stx2), produced by Shiga toxin-producing Escherichia coli (STEC) and Shigella dysenteriae, are key virulence factors responsible for severe foodborne diseases, such as hemorrhagic colitis and hemolytic uremic syndrome (HUS). The receptors for Stxs are Gb3 and P1 glycotope, which contain the Galα1→4Galβ epitope and are synthesized by human α1,4-galactosyltransferase (A4galt). Stx-related infections pose a global public health challenge, owing to the limited therapeutic options due to the restricted use of antibiotics. Therefore, there is an urgent need to develop novel therapeutic strategies. This study proposes an innovative strategy utilizing exosomes derived from CHO-Lec2 cells, which were modified with Functional-Spacer-Lipid (FSL) conjugates bearing the Gb3 carbohydrate epitope (exo-Gb3-FSL). Flow cytometry analysis confirmed the presence of Galα1→4Galβ disaccharides on exo-Gb3-FSL constructs, enabling them to bind Stx1. Moreover, using CHO-Lec2 cells verified the ability of exo-Gb3-FSL agents to bind Stx1 and protect these cells from Stx1-mediated cytotoxicity. For Stx1-treated CHO-Lec2 cells, increased cell survival was observed when using 25 μM exo-Gb3-FSL constructs, compared to control cells. These findings highlight the potential of exosome-based anti-Stx1 agents as promising alternatives to conventional therapies. This innovative strategy may provide novel directions for studies on Stx1 neutralization, offering a valuable strategy for the treatment of Stx-related diseases.

Facile fabrication and characterization of carboxymethyl cellulose loaded with TiO2NPs hydrogel as a promising disinfectant for eliminating the dissemination of waterborne pathogens through wastewater decontamination

The purpose of this work was to develop and characterize an intriguing hydrogel called TiO₂NPs@CMC hydrogel, which is composed of carboxymethyl cellulose (CMC) and loaded with titanium oxide nanoparticles (TiO₂NPs) for effective waterborne pathogen disinfection in wastewater. The TiO₂NPs were synthesized through hydrolysis and peptization, incorporated into a CMC matrix, and subsequently cross-linked with calcium chloride (CaCl₂). Characterization through TEM, FTIR, and SEM validated the development of a porous structure, efficient incorporation of TiO₂NP, and successful crosslinking. In this study, TiO2NPs were prepared and affirmed the significant particle distribution with a small size using TEM. The TiO₂NPs@CMC hydrogel exhibited significant antimicrobial and antibiofilm properties against various pathogens, such as Salmonella typhi, E. coli O157, Shigella dysenteriae, Enterococcus faecalis, Bacillus cereus, and Candida albicans, with highest inhibition zone diameters of up to 29 mm for S. typhi. The inhibitory effect demonstrated that the hydrogel significantly decreased bacterial populations at 100 μg/mL concentrations. The hydrogel demonstrated a 2.7-log reduction in microbial counts in sewage water within 120 min, achieving complete inactivation of pathogens at a concentration of 2xMIC within 180 min. The biofilm inhibition rate reached 87.6 % against B. cereus. Toxicity assessments demonstrated significant biocompatibility, with no negative effects noted in environmental applications. The findings indicate that TiO₂NPs@CMC hydrogel is a viable option for sustainable wastewater treatment, providing an efficient, safe, and environmentally friendly method for the removal of waterborne pathogens and the prevention of biofilm formation.

The Current Prevalence of the Food-Borne Shigella Spp in Local Stored Cheese in Al-Diwaniyah City, Iraq: The Virulence ipaH and uidA Genes as Targets for a Molecular Study

The current study was carried out to evaluate the current prevalence of the food-borne pathogen; Shigella spp., in local stored cheese in Al-Diwaniyah City, Iraq, by using the virulence ipaH and uidA genes as targets for molecular tools. The study included the bacterial cultivation of 450 local cheese samples (collected during June to September, 2022) utilizing conventional methodology. The recovered Shigella spp. isolates were subjected to a real-time PCR (RT-PCR) that focused on the genes mentioned above. The results of the cultivation revealed the presence of 110 (24.4%) Shigella spp. isolates in the examined cheese samples. The RT-PCR showed that the virulence genes were identified in 84 (76.4%) and 98 (89.1%), respectively, in the bacterial isolates, which indicated the existence of Shigella dysenteriae. The current findings indicate the presence of Shigella spp. in local cheese, which needs urgent control to eliminate the source of infection or contamination.

Eco-friendly synthesis of curcumin-loaded ZnO nanoparticles encapsulated in Pluronic F-127: Implications for bacterial and breast cancer therapies

The development of a nanomaterials production process that is both economical and environmentally friendly is a result of the growing importance placed on people’s health. The Zinc oxide (ZnO)-Pluronic F127 (PF127)-Curcumin (CUR) nanoparticles (NPs) were synthesized through a green method using Senna auriculata flower extracts. These NPs were characterized using a variety of techniques, such as ultraviolet–visible spectroscopy (UV), Fourier transform infrared spectroscopy (FTIR), Field emission scanning electron microscopy (FESEM), Energy Dispersive X-ray analysis (EDAX), X-ray diffraction (XRD), photoluminescence (PL), and dynamic light scattering (DLS). From the XRD studies, synthesized ZnO-PF127-CUR NPs exhibit a wurtzite hexagonal crystal structure. The antimicrobial activity of ZnO-PF127-CUR NPs and Amoxicillin was tested against Staphylococcus aureus, Klebsiella pneumoniae, Shigella dysenteriae, Staphylococcus pneumoniae, Bacillus subtilis, proteus vulgaris, and candida albicans, respectively. The anticancer activity of ZnO-PF127-CUR NPs was tested against human breast cancer cell line (MDA-MB-237), and ZnO-PF127-CUR exhibits potential anticancer activity. These results support using ZnO-PF127-CUR NPs in healthcare manufacturing environments to improve human health.

Bioactivity of biogenic silver/silver chloride nanoparticles from Maranta arundinacea rhizome extract: Antibacterial and antioxidant properties with anticancer potential against Ehrlich ascites carcinoma and human breast cancer cell lines

IntroductionThis study explores the synthesis and characterization of silver/silver chloride nanoparticles (Ag/AgCl-NPs) using Maranta arundinacea rhizome extract and evaluates their bioactivities, including antibacterial, antioxidant, and anticancer potentials. MethodsThe synthesis of Ag/AgCl-NPs was initially confirmed by a color change and a sharp peak at 463 nm in UV–visible spectroscopy. Further characterization was conducted using scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and fourier transform infrared spectroscopy (FTIR). Antibacterial properties were checked against four pathogenic bacteria (Shigella boydii, Escherichia coli, Shigella dysenteriae, and Staphylococcus aureus), and antioxidant activities were assessed using DPPH (2,2-diphenyl-1-picrylhydrazyl) and ABTS (2,2-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid) assay. In addition, the anticancer potential was evaluated in vitro using MTT (3-(4, 5-dimethylthiazolyl-2)-2, 5-diphenyltetrazolium bromide) colorimetric assay and in vivo using the mouse models. Finally, toxicity was determined by employing the brine shrimp nauplii lethality assay. ResultsAg/AgCl-NPs most effectively inhibited the growth of Staphylococcus aureus, showing maximum zone of inhibition and 7 μg/mL of minimum inhibitory concentration (MIC), and prevented the biofilm formation by Escherichia coli at 40 μg/mL. They displayed antioxidant activities against DPPH and ABTS with IC50 values of 90.65 and 24.34 μg/mL, respectively. In vitro, they inhibited 61.96 % EAC and 49.63 % MCF-7 cells growth at 32 and 128 μg/mL, respectively. Subsequently, inhibition rates of EAC cells growth in mice were measured as 38.30 %, 57.38 %, and 31.81 % after employing 2.5, 5, and 10 mg/kg/day of Ag/AgCl-NPs, respectively. Moreover, Ag/AgCl-NPs treated mice were found to carry more apoptotic EAC cells with distorted morphology. Treated mice showed decreased tumor weight, increased mean survival time, and a lifespan increase of up to 30 %, with improved hematological parameters. Later, Ag/AgCl-NPs exhibited moderate toxicity with an LC50 value of 208.41 μg/mL in brine shrimp nauplii lethality assay. ConclusionThe promising antibacterial, antioxidant, and anticancer activities along with mild toxicity suggest the potential biomedical uses of Maranta arundinacea rhizome extract-mediated Ag/AgCl-NPs.

Fortification of cotton fabrics with dithiocarbamate-metal complexes to prepare durable antimicrobial fabrics

In this study, a simple and practical method is reported to fortify cotton fabrics with dithiocarbamate (DTC-Ct), dithiocarbamate-Cu (Cu-Ct) and dithiocarbamate-Ni (Ni-Ct) complexes via impregnation process to prepare durable antimicrobial fabrics. FTIR analysis indicates the presence of characteristic peaks corresponding to cellulose functional groups in the fortified fabrics. SEM micrographs illustrate the transition from a closed-packed, smooth surface in untreated cotton to a rough texture enveloped with metal complexes in fortified fabrics. EDX images confirm successful impregnation, with prominent peaks due to C and O in the untreated cotton, while additional signals of S, Cu, and Ni were observed in the fortified samples. TEM images revealed irregular, spherical nanoparticles within fortified cotton, compared with the rough surface of untreated fabrics. The average size of the treated cotton fabric fell within the range of 2.20–7.32, 3.83–28.50, and 2.70–7.32 nm for DTC-Ct, Cu-Ct and Ni-Ct, respectively. Untreated cotton fabric exhibits no inherent antibacterial properties, whereas fortified cotton fabrics demonstrate enhanced antibacterial efficacy against strains including Salmonella typhi, Enterobacter aerogenes, Shigella dysenteriae, and Klebsiella pneumonia, with Ni-Ct-fortified cotton proving most effective. Furthermore, the durability of additive adhesion to cotton fabrics was evaluated through washing tests, revealing robust adherence even after multiple cycles, with sustained antimicrobial inhibition observed for up to five wash cycles.

Multidrug-Resistant Proteus mirabilis and Other Gram-Negative Species Isolated from Native Egyptian Chicken Carcasses.

Poultry carcasses may be reservoirs for the zoonotic transmission of antimicrobial-resistant bacteria to humans and pose a major public health hazard. During the isolation of Salmonella from poultry and other foods, many of the presumptive typical Salmonella colonies on xylose lysine deoxycholate (XLD) agar were found to lack the invA gene, which is the specific target gene for Salmonella spp. Therefore, the current study aimed to estimate the prevalence and antimicrobial resistance profiles of extensively drug-resistant invA-negative non-Salmonella isolates recovered from native Egyptian chicken carcasses as presumptive Salmonella colonies on XLD agar. The non-Salmonella isolates were detected in 84% (126/150) of the examined native Egyptian chicken carcasses and classified into five genera, with prevalence rates of 64% (96/150), 14% (21/150), 6.7% (10/150), 3.3% (5/150), and 1.3% (2/150) for Proteus, Citrobacter, Shigella, Pseudomonas, and Edwardsiella, respectively. One hundred and ninety-five invA-negative, non-verified presumptive Salmonella isolates were recovered and classified at the species level into Proteus mirabilis (132/195; 67.7%), Proteus vulgaris (11/195; 5.6%), Citrobacter freundii (26/195; 13.3%), Shigella flexneri (8/195; 4.1%), Shigella sonnei (6/195; 3.1%), Shigella dysenteriae (3/195; 1.5%), Pseudomonas fluorescens (6/195; 3.1%), and Edwardsiella tarda (3/195; 1.5%). All (195/195; 100%) of these isolates showed resistance against cefaclor and fosfomycin. Additionally, these isolates showed high resistance rates of 98%, 92.8%, 89.7%, 89.2%, 89.2%, 86.7%, 80%, 78.5%, 74.4%, and 73.9% against cephalothin, azithromycin, vancomycin, nalidixic acid, tetracycline, sulfamethoxazole/trimethoprim, cefepime, gentamicin, cefotaxime, and ciprofloxacin, respectively. Interestingly, all (195/195; 100%) of the identified isolates were resistant to at least five antibiotics and exhibited an average MAR (multiple antibiotic resistance) index of 0.783. Furthermore, 73.9% of the examined isolates were classified as extensively drug-resistant, with an MAR index equal to 0.830. The high prevalence of extensively drug-resistant foodborne Proteus, Citrobacter, Shigella, Pseudomonas, and Edwardsiella isolated from native chicken carcasses poses a great hazard to public health and necessitates more monitoring and concern about the overuse and misuse of antibiotics in humans and animals. This study also recommends the strict implementation of GHP (good hygienic practices) and GMP (good manufacturing practices) in the chicken meat supply chain to protect consumer health.

Green synthesis of copper oxide nanoparticles using Ficus racemosa leaf extract and investigation of its antibacterial properties

ABSTRACT The present work reports a one-pot green synthesis of copper oxide nanoparticles (CuO NPs) using Ficus racemosa leaf extract via a green chemistry approach without using any harsh chemical reagents. The crystalline and single-phase CuO NPs were analysed via XRD. DLS revealed the average particle size distribution, and zeta potential was used for the evaluation of surface charge. Optical properties were determined at 530 nm through UV–Vis spectroscopy with a broad peak in the range from 500 to 590 nm. Different functional groups in the leaf extract containing flavonoids and polyphenols as reducing agents responsible for the synthesis of CuO NPs were verified through FTIR. The FESEM images revealed the average particle size in the range from 30 to 300 nm with a spherical morphology, and EDS was used for the quantitative elemental analysis. The strong bacterial inhibition tendency of CuO NPs against 12 bacterial strains including Bacillus cereus, Campylobacter jejuni, Bacillus subtilis, Clostridium perfringens, Staphylococcus aureus, Escherichia coli, Streptococcus pyogenes, Vibrio cholerae, Shigella dysenteriae, Listeria monocytogenes, Helicobacter pylori, and Salmonella typhi was observed with MIC values between 60 and 1000 µg/mL. The findings suggest that the synthesis of CuO NPs via green chemistry can serve as a potential substitute for traditional multi-step chemical synthetic routes.

Enhancement of antimicrobial properties and cytocompatibility through silver and magnesium doping strategies on copper oxide nanocomposites

In the present study, silver (Ag), magnesium (Mg), and the various molar ratios of Ag:Mg-doped copper oxide nanocomposites (CuO NCs) were synthesized by the co-precipitation method. The CuO NC samples calcined at 500 °C were further analyzed for their morphological, structural, functional, and optical properties. Adding single and dual doping increased the pristine CuO band gap from 1.28 to 1.50 eV. The Ag and Mg metal peaks were revealed in the Fourier transform infrared (FTIR) analysis, while an elevated Mg band was observed in all Mg-doped samples in the Raman results. All CuO NCs showed a monoclinic crystalline structure, flake, and rod-like morphologies. Microbes of Bacillus subtilis, Shigella dysenteriae, and Candida albicans were tested against different concentrations of CuO NCs. Better results for all tested microbes were observed with the 2 mg concentration. The high cytotoxicity effect was observed in the pristine and Cu:Ag (94:6) sample, and other CuO NCs, which demonstrated over 80 % viability in RAW 246.7 cells at a concentration of 0.5 µg/ml. Remarkably, over 94 % cell viability at 0.5 µg/ml was achieved with the Cu:Ag:Mg (94:3:3) NCs ratio, owing to the synergistic effect of the ion-releasing ability of Cu2+, Ag2+, and Mg2+ ions. It possesses a distinctive high aspect ratio shape, is ion-releasing, and has excellent cytocompatibility. The suitability of the Cu:Ag:Mg (94:3:3) NCs ratio for addressing microbial challenges in healthcare is suggested by their distinct characteristics, indicating the promising potential for future biomedical applications.

Novel α-N-heterocyclic thiosemicarbazone complexes: synthesis, characterization, and antimicrobial of properties investigation.

In this paper, eight novel α-N-heterocyclic thiosemicarbazone complexes were synthesized in search of new biologically active compounds, and characterized via organic elemental analysis, nuclear magnetic resonance spectroscopy, infrared spectra, thermogravimetric analysis, ultraviolet-visible spectroscopy, molar conductance and magnetic susceptibility measurements. The in vitro antimicrobial activity of these complexes was examined against ten disease-causing pathogens: Gram-positive bacteria (Micrococcus luteus ATCC9341, Staphylococcus epidermidis ATCC12228, Bacillus cereus RSKK863) and Gram-negative bacteria (Pseudomonas aeroginosa ATCC27853, Klebsiella pneumonia ATCC27853, Enterobacter aerogenes ATCC51342, Salmonella typhi H NCTC9018394, Shigella dysenteria NCTC2966, Proteus vulgaris RSKK96026) and yeast (Candida albicans Y-1200-NIH). The results revealed that the α-N-heterocyclic thiosemicarbazone compounds showed potent activity. It was observed that all thiosemicarbazone complexes were more susceptible to Gram-negative strains based on the presence of an electron-withdrawing substituent (-Br/-Cl/-F). It was determined that thiosemicarbazone Cu2+complexes showed stronger antifungal effects.

Genome Analysis of a Potential Novel Vibrio Species Secreting pH- and Thermo-Stable Alginate Lyase and Its Application in Producing Alginate Oligosaccharides.

Alginate lyase is an attractive biocatalyst that can specifically degrade alginate to produce oligosaccharides, showing great potential for industrial and medicinal applications. Herein, an alginate-degrading strain HB236076 was isolated from Sargassum sp. in Qionghai, Hainan, China. The low 16S rRNA gene sequence identity (<98.4%), ANI value (<71.9%), and dDDH value (<23.9%) clearly indicated that the isolate represented a potential novel species of the genus Vibrio. The genome contained two chromosomes with lengths of 3,007,948 bp and 874,895 bp, respectively, totaling 3,882,843 bp with a G+C content of 46.5%. Among 3482 genes, 3332 protein-coding genes, 116 tRNA, and 34 rRNA sequences were predicted. Analysis of the amino acid sequences showed that the strain encoded 73 carbohydrate-active enzymes (CAZymes), predicting seven PL7 (Alg1-7) and two PL17 family (Alg8, 9) alginate lyases. The extracellular alginate lyase from strain HB236076 showed the maximum activity at 50 °C and pH 7.0, with over 90% activity measured in the range of 30-60 °C and pH 6.0-10.0, exhibiting a wide range of temperature and pH activities. The enzyme also remained at more than 90% of the original activity at a wide pH range (3.0-9.0) and temperature below 50 °C for more than 2 h, demonstrating significant thermal and pH stabilities. Fe2+ had a good promoting effect on the alginate lyase activity at 10 mM, increasing by 3.5 times. Thin layer chromatography (TLC) and electrospray ionization mass spectrometry (ESI-MS) analyses suggested that alginate lyase in fermentation broth could catalyze sodium alginate to produce disaccharides and trisaccharides, which showed antimicrobial activity against Shigella dysenteriae, Aeromonas hydrophila, Staphylococcus aureus, Streptococcus agalactiae, and Escherichia coli. This research provided extended insights into the production mechanism of alginate lyase from Vibrio sp. HB236076, which was beneficial for further application in the preparation of pH-stable and thermo-stable alginate lyase and alginate oligosaccharides.

In silico study exploiting chromosomal replication initiator protein as a molecular target for new antibiotics in Shigella dysenteriae

Introduction: DNA chromosomal replication initiator protein, DnaA is a component of bacterial division machinery. Objetives: virtual screening of phytochemicals for new antibiotics at novel molecular targets. Materials and Methods: SWISS-Model tool was used in homology modeling of this protein and validation tools were also used to check for its accuracy. The evaluation tools were ERRAT, PROCHECK and Molprobity servers. The refined model by GalaxyWEB server, then employed in molecular docking experiments. A total of 300 natural products were used in virtual screening for lead compounds targeting the model by AutoDock Vina software. Results and Discussion: Corylin among then best ligands that have binding affinities lower than ADP as control. Interactions in the form of hydrogen bonds and hydrophobic interactions were analyzed by LigPlot. The best compounds were submitted into iGEMDOCK docking tool for consensus scoring approach. admetSAR 2.0 was used to predict for pharmacokinetics, interactions and toxicities of these ligands inside the human body. Conclusions: Therefore, preliminary screening of lead compounds must be accompanied by studying pharmacologic properties.

Bio‐Extract Mediated Synthesis of Y/Fe2O3 Nanoparticles Using Adenanthera pavonina L. and Their Photocatalytic and Antibacterial Activities

AbstractThe present study uses Adenanthera pavonina L. plant extract to synthesize Y/Fe2O3 nanoparticles in a sustainable and efficient manner. Several physicochemical investigations were performed on the synthesized Y/Fe2O3 to evaluate its structure and morphological characteristics. The high crystallinity of Fe2O3 and decreased crystal size of Y/Fe2O3 were revealed by the XRD study. The formulated Y/Fe2O3 was spherical in shape. Y/Fe2O3 has shown potential photocatalytic activity in the degradation of congo red and brilliant green dyes in the presence of visible light. Degradation efficiency is higher than 90% for both dyes. In addition, the antibacterial activity of Y/Fe2O3 was measured against pathogenic strains of Bacillus subtilis, Escherichia coli, Klebsiella pneumoniae, Micrococcus luteus, Proteus mirabilis, Pseudomonas putida, Shigella dysenteriae, and Staphylococcus aureus. Y/Fe2O3 showed promising antibacterial activity against all microorganisms. Micrococcus luteus showed a higher zone of inhibition (equal to 35 mm in diameter) than other microorganisms using Y/Fe2O3. Thus, it is established that the green synthesized Y/Fe2O3 nanoparticles are active catalysts for the photocatalytic degradation of hazardous dyes and have antibacterial properties against different bacterial stains.

Antimicrobial metabolites from Probiotics, Pleurotus ostreatus and their co-cultures against foodborne pathogens isolated from ready-to-eat foods

BackgroundThe 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.ResultsFrom 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%).ConclusionRTE 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.

Investigating the synergistic antibacterial effects of chlorogenic and p-coumaric acids on Shigella dysenteriae

Chlorogenic acid (CGA) is a well-known plant secondary metabolite exhibiting multiple physiological functions. The present study focused on screening for synergistic antibacterial combinations containing CGA. The combination of CGA and p-coumaric acid (pCA) exhibited remarkably enhanced antibacterial activity compared to that when administering the treatment only. Scanning electron microscopy revealed that a low-dose combination treatment could disrupt the Shigella dysenteriae cell membrane. A comprehensive analysis using nucleic acid and protein leakage assay, conductivity measurements, and biofilm formation inhibition experiments revealed that co-treatment increased the cell permeability and inhibited the biofilm formation substantially. Further, the polyacrylamide protein- and agarose gel-electrophoresis indicated that the proteins and DNA genome of Shigella dysenteriae severely degraded. Finally, the synergistic bactericidal effect was established for fresh-cut tomato preservation. This study demonstrates the remarkable potential of strategically selecting antibacterial agents with maximum synergistic effect and minimum dosage exhibiting excellent antibacterial activity in food preservation.

Isolation and investigation of antibacterial activities and cytotoxicity of atropine and scopolamine

Medicinal plants contain various secondary metabolites, such as alkaloids, polyphenols, terpenes, tannins, terpenoids, and flavonoids. These compounds are important sources for treating numerous diseases. Datura stramonium, a plant from the Solonaceae family, is rich in alkaloids, glycosides, terpenoids, steroids, flavonoids, tannins, and saponins. Over time, this plant has demonstrated significant therapeutic effects. The objective of this study was to extract atropine and scopolamine compounds, which are alkaloids found in D. stramonium leaves, and investigate their antibacterial and cytotoxic effects. Atropine and scopolamine were isolated from D. stramonium and analyzed using high-performance chromatography (HPLC) and carbon and proton NMR (NMR H1, C13). The antibacterial activity of atropine and scopolamine against Shigella dysenteriae (PTCC 1188), Streptococcus pyogenes (ATCC 19615), and Staphylococcus epidermidis (CIP 81.55) was investigated using the disc diffusion and microdilution methods. The cytotoxic activity on AsPC-1 (pancreatic adenocarcinoma), MCF-7 (breast cancer), and ACHN (renal carcinoma) cell lines was studied using the MTT reagent assay method. Both compounds exhibited the highest antibacterial activity against S. dysenteriae, while the lowest antibacterial activity was observed against S. pyogenes. All three cancer cell lines were treated with different concentrations of atropine and scopolamine for 24 and 48 h. The results of both extracts showed that increasing the concentration of the extracts decreased the viability of all three cell lines. The IC50 values of both extracts were measured at 24 and 48 h. Preliminary results confirm the therapeutic potential of these two compounds, but further studies are required to investigate there in vivo effects.