Search Results (33)

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease which seriously affects public health. Gut microbiota remains a dynamic balance state in healthy individuals, and its disorder may affect health status and even results in metabolic diseases. Quercetin, a natural flavonoid, has been shown to have biological activities that can be used in the prevention and treatment of metabolic diseases. This study aimed to explore the mechanism of quercetin in alleviating T2DM based on gut microbiota. db/db mice were adopted as the model for T2DM in this study. After 10 weeks of administration, quercetin could significantly decrease the levels of body weight, fasting blood glucose (FBG), serum insulin (INS), the homeostasis model assessment of insulin resistance (HOMA-IR), monocyte chemoattractant protein-1 (MCP-1), D-lactic acid (D-LA), and lipopolysaccharide (LPS) in db/db mice. 16S rRNA gene sequencing and untargeted metabolomics analysis were performed to compare the differences of gut microbiota and metabolites among the groups. The results demonstrated that quercetin decreased the abundance of Proteobacteria, Bacteroides, Escherichia-Shigella and Escherichia_coli. Moreover, metabolomics analysis showed that the levels of L-Dopa and S-Adenosyl-L-methionine (SAM) were significantly increased, but 3-Methoxytyramine (3-MET), L-Aspartic acid, L-Glutamic acid, and Androstenedione were significantly decreased under quercetin intervention. Taken together, quercetin could exert its hypoglycemic effect, alleviate insulin resistance, repair the intestinal barrier, remodel the intestinal microbiota, and alter the metabolites of db/db mice. Full article

Enteroaggregative Escherichia coli (EAEC) has been widely recognized as one of the leading causes of infantile diarrhoea and nutrient malabsorption in developing as well as developed countries. In recent years, drug resistance, particularly multi-drug resistance (MDR), among the EAEC strains has been widely documented and could result in a therapeutic stumble. Antimicrobial alternatives are widely employed to curb this emerging public health crisis. In the present study, a facile one-pot synthesis of silver/zinc oxide nanocomposites (Ag/ZnO NCs) using a methanolic extract of stem and leaves of Curcuma longa was performed. The synthesis of Ag/ZnO NCs was confirmed using UV-vis spectroscopy and Fourier transform infrared spectroscopy, while the thermal stability was ascertained by thermogravimetric analysis with differential thermogravimetric analyses, and crystallinity was determined using powder X-ray diffraction. The shape and size of the green synthesized Ag/ZnO NCs, determined using field-emission–scanning-electron microscopy and transmission electron microscopy, revealed an irregular polycrystalline morphology with a size of 31.34 ± 1.27 nm. Later, the antibacterial potential of the green synthesized Ag/ZnO NCs evaluated against MDR- EAEC strains revealed a minimum inhibitory concentration of 31.25 μg/mL and a minimum bactericidal concentration ranging from 62.50 to 125 μg/mL. Moreover, the green synthesized Ag/ZnO NCs inhibited the biofilm-forming ability of the tested strains of MDR-EAEC. Furthermore, concentration-dependent antioxidant activity was exhibited by the green synthesized Ag/ZnO NCs, as evidenced by the ABTS assay and reducing power assay. Overall, this study demonstrated the antibacterial potential of Ag/ZnO NCs synthesized using C. longa extracts with antifouling as well as antioxidant properties, which could be used as an alternative therapeutic candidate. Full article

Propolis is a resinous compound produced by honey bees. It contains bioactive molecules that possess a wide range of biological functions. The chemical composition of propolis is affected by various variables, including the vegetation, the season, and the area from which the sample was collected. The aim of this study was to analyze the chemical composition and assess Cerana indica propoli’s antibacterial efficacy from the Kashmir region. Gas chromatography-mass spectrometry (GC-MS) analysis was used to determine the chemical composition of Kashmiri propolis. A range of bacterial strains was tested for antimicrobial activity using different extracts of propolis by agar well diffusion technique. Propolis was found to be rich in alkaloids, saponins, tannins, and resins. The chemical characterization revealed the presence of 68 distinct phytocompounds using GC-MS, and the most predominant compounds were alpha-D-mannopyranoside, methyl, cyclic 2,3:4,6-bis-ethyl boronate (21.17%), followed by hexadecanoic acid, methyl ester (9.91%), and bacteriochlorophyll-c-stearyl (4.41%). The different extracts of propolis showed specific antibacterial efficacy against multidrug-resistant (MDR) strains viz., Pseudomonas aeruginosa (MTCC1688), Escherichiacoli (MTCC443), Klebsiella pneumonia (MTCC19), Cutibacterium acnes (MTCC843), and Staphylococcus aureus (MTCC96). The EEKP showed the highest zone of inhibition against S. aureus (17.33) at 400 µg mL⁻¹. According to the findings of this study, bee propolis contains a variety of secondary metabolites with various pharmacological activities. Furthermore, because of its broad spectrum of positive pharmacological actions and the fact that it is a promising antibacterial agent, more research on propolis is warranted. Full article

There is a global trend toward intensive livestock breeding, which tends to increase the microbial load in the environment as well as the presence of volatile compounds and dust that can cause health issues. Cattle is the major producer of Escherichiacoli (E. coli), a group of foodborne bacteria associated with severe human diseases, and Neuquén province in Argentina has one of the highest rates of uremic hemolytic syndrome incidence in the world. This paper presents the results of two sampling events of E. coli bacteria at 39 sites in La Paisana ranch (LPR), in Añelo (Neuquén), considering locations inside the pens, upwind, and downwind of the feedlot with different time steps, using a Microflow α equipment. The ranch has approximately 600 heads and clean and controlled installations. The field experiment included sampling airborne aerosol deposition and concentration using passive and active methods. Concentrations were also estimated using an atmospheric dispersion model. During the field experiment, counts of up to 2970 CFU/m³ were obtained in the cattle stockyards and up to 111 CFU/m³ at a distance of 100 m. Full article

Nowadays, the use of antimicrobial natural agents as alternative food preservatives represents an intriguing case. The purpose of this study was to investigate possible antimicrobial activity of Pistacia lentiscus and Fortunella margarita essential oils (EOs) and to evaluate their commercial potential in the food industry. The main constituents identified by GC/MS in Pistacia lentiscus EO were a-pinene (67.7%), myrcene (18.8%), and β-pinene (3.0%), whereas limonene (93.8%) and myrcene (2.7%) were the dominant compounds in Fortunella margarita EO. The antimicrobial properties were initially assayed and the minimum inhibitory, non-inhibitory, and minimum lethal concentration values against the Escherichiacoli, Listeria monocytogenes, Pseudomonas fragi, Aspergillus niger, and Saccharomyces cerevisiae were determined using a previously published model, combining absorbance measurements with the common dilution method and non-linear regression analysis to fit the data. Their efficiency was further validated in ice cream containing 0.2% (w/w) Pistacia lentiscus, 0.006% (w/w) Fortunella margarita EOs and 2% (w/w) aqueous residue of F. margarita EO deliberately inoculated with 4 logcfu/g Escherichiacoli, Listeria monocytogenes or Pseudomonas fragi, separately. Similarly, the activity of the oils was monitored in fruit juice (lemon, apple, and blackcurrant) containing 0.2% (w/w) Pistacia lentiscus, 0.006% (w/w) Fortunella margarita EOs and 2% (w/w) aqueous residue of F. margarita EO deliberately spiked with 100 spores/mL of Aspergillus niger or 4 logcfu/mL of Saccharomyces cerevisiae, separately. The results showed that microbial viable counts in the supplemented products ranged at significantly lower levels compared to the control samples during storage. Overall, the data indicated that both EOs constitute effective antimicrobial sources with many potent applications in the food industry. Full article

Scaling up the production of functional reduced graphene oxide (rGO) and its composites requires the use of low-cost, simple, and sustainable synthesis methods, and renewable feedstocks. In this study, silver oxide-decorated rGO (Ag_xO−rGO) composites were prepared by open-air combustion of mustard oil, essential oil-containing cooking oil commercially produced from the seeds of Brassica juncea. Silver oxide (Ag_xO) nanoparticles (NPs) were synthesized using Coleus aromaticus leaf extract as a reducing agent. Formation of mustard seed rGO and Ag_xO NPs was confirmed by UV-visible characteristic peaks at 258 nm and 444 nm, respectively. rGO had a flake-like morphology and a crystalline structure, with Raman spectra showing clear D and G bands with an I_D/I_G ratio of 0.992, confirming the fewer defects in the as-prepared mustard oil-derived rGO (M−rGO). The rGO-Ag_xO composite showed a degradation efficiency of 81.9% with a rate constant k⁻¹ of 0.9506 min⁻¹ for the sodium salt of benzidinediazo-bis-1-naphthylamine-4-sulfonic acid (known as the azo dye Congo Red) in an aqueous solution under visible light irradiation. The composite also showed some antimicrobial activity against Klebsilla pneomoniae, Escherichiacoli, and Staphylococcusaureus bacterial cells, with inhibition zones of ~15, 18, and 14 mm, respectively, for a concentration of 300 µg/mL. At 600 µg/mL concentration, the composite also showed moderate scavenging activity for 2,2-diphenyl-1-picrylhydrazyl of ~30.6%, with significantly lower activities measured for Ag_xO (at ~18.1%) and rGO (~8%) when compared to control. Full article

Background: Many studies have reported minor complications and disturbance of the gut microbiota after colonoscopy. Compared with air, carbon dioxide (CO₂) insufflation could decrease minor complications, but its impact on gut microbiota remains unknown. Methods: Thirty-eight healthy subjects were assessed and twenty were randomized to receive either CO₂ or air insufflation during colonoscopy. Neither the participants nor the staff involved in the follow-up knew which gas was used. Minor complications were assessed using symptom scores. Fecal samples were collected at eight time-points for microbiome analysis by full-length 16S rRNA gene amplicon analysis. Results: Baseline characteristics were similar in both groups. The recovery of minor complications after colonoscopy was faster in the CO₂ group (the day of the colonoscopy) than in the air group (the day after the colonoscopy). There was no significant reduction in alpha diversity (species richness) of the first stool after colonoscopy in the CO₂ group (115.0 ± 32.81 vs. 97.4 ± 42.31, p = 0.28) compared with the air group (123.8 ± 37.25 vs. 84.8 ± 31.67, p = 0.04). However, there were no differences in beta diversity between the groups. Linear discriminant analysis effect size (LEfSe) analysis indicated that anaerobic probiotics such as Bacteroides caccae, Bacteroides finegoldii and Bacteroides thetaiotaomicron were more abundant in the CO₂ group than in the air group within 14 days after colonoscopy. On the contrary, the content of Escherichiacoli, Ruminococcus torques and Ruminococcus guavus was higher in the air group. Conclusions: CO₂ is beneficial to gut microbiota homeostasis during colonoscopy in healthy subjects. The effects in patients with different diseases need to be further studied. Full article

(1) Background: Bacitracin is a broad spectrum antibiotic that is used against various microorganisms. Chitosan is a natural polymer that has been widely investigated as an antimicrobial agent for preventing and treating infections owing to its intrinsic antimicrobial properties, as well as its ability to effectively deliver extrinsic antimicrobial compounds to infected areas. Topical drug delivery offers important benefits for improving the therapeutic effect and reducing systemic side effects of administered compounds/drugs. The topical use of chitosan-decorated bacitracin-loaded cream improves the permeation of the drug across the skin and enhances the drug bioavailability by prolonging the residence time of the drug when applied topically, as well as producing synergistic effects and reducing the side effects of the drug. Topical chitosan-decorated cream can be a promising approach to administer the drug more efficiently and enhance the efficacy of treatment in wound healing and antibacterial activity. (2) Methods: This study was conducted to prepare, assess and investigate the synergistic antibacterial activity of a chitosan-coated bacitracin cream. The results were compared to the antibacterial activity of simple bacitracin-loaded cream. The prepared cream was evaluated for various in vitro characteristics such as rheology, pH, viscosity, drug content and antibacterial activity studies. (3) Result: The formulations were found to be stable regarding color, liquefaction and phase separation at all accelerated conditions. It was observed that with time, substantial variations in the pH of the preparations were found. The introduction of chitosan results in controlled release of the drug from the formulations. The antibacterial activity of the formulated creams was assessed with the disc diffusion method against Staphylococcus aureus(ATCC),Escherichiacoli (STCC),Pseudomonas aeruginosa(ATCC) and Bacillus cereus(ATCC). The strains, E. coli, S. aureus, P. aeruginosa and B. cereus were susceptible to 50 µg chitosan-decorated bacitracin cream, showing inhibition zones of 10 ± 0.6, 34 ± 1.5, 31 ± 0.76 and 21 ± 2.02 mm, respectively. The zones of inhibition for simple bacitracin-loaded cream were significantly smaller than chitosan-decorated cream, at 2 ± 0.2, 28 ± 0.92, 15 ± 0.5 and 11 ± 1.25 mm (ANOVA; p < 0.05), respectively. (4) Conclusion: It was observed that the zones of inhibition of simple bacitracin-loaded cream were significantly smaller than those of chitosan-decorated bacitracin-loaded cream. Chitosan synergistically improves the antimicrobial activity of bacitracin. Hence, the developed formulation was effective and should be considered as a suitable candidate for topical management of skin infections and wound healing. Full article

G-quadruplexes (G4s) are a unique class of noncanonical DNAs that play a key role in cellular processes and neoplastic transformation. Herein, we focused on the promoter region of human TERT oncogene, whose product is responsible for the immortality of cancer cells. It has been shown by chemical probing and spectroscopic methods that synthetic 96-nt DNAs modeling the wild-type G-rich strand of the hTERT promoter and its variants with G>A point substitutions corresponding to somatic driver mutations fold into three stacked parallel G4s with sites of local G4 destabilization caused by G>A substitutions in the G4 motif. These models were used to elucidate how the hTERT multiG4 affects the binding affinity and functional responses of two key proteins, MutS and MutL, involved in the initial stage of DNA mismatch repair (MMR) in Escherichiacoli and Neisseriagonorrhoeae with different MMR mechanisms. We have shown for the first time that (i) point substitutions do not affect the effective binding of these proteins to the hTERT G4 structure, and (ii) the endonuclease activity of MutL from N. gonorrhoeae is significantly suppressed by the stable G4 scaffold. It is likely that some of the genomic instability associated with G4 may be related to the blockage of human intrinsic methyl-independent MMR attempting to operate near G4 structures. Full article

Coumarin is highly distributed in nature, notably in higher plants. The biological features of coumarin include antibacterial, anticancer and antioxidant effects. It is well known that metal ions present in complexes accelerate the drug action and the efficacy of organic therapeutic agents. The main aim of the current study is the synthesis of different complexes of the interaction between ciprofloxacin hydrochloride (CIP) and coumarin derivative 7-hydroxy-4-methylcoumarin (HMC) with Zr(IV). The chelates of CIP with Zr(IV) were prepared and characterized by elemental analysis, melting point, conductance measurements, spectroscopic techniques involving IR, UV-Vis, ¹H NMR, and thermal behavior (TG-DTG) in the presence of HMC, dimethylformamide (DMF), pyridine (Py), and triethylamine (Et₃N). Results of molar conductivity tests showed that the new synthesized complexes are electrolytes with a 1:1 or 1:2 electrolyte ratio, with the chloride ions functioning as counter ions. According to IR spectra, CIP acts as a neutral bidentate ligand with Zr(IV) through one carboxylato oxygen and the carbonyl group, HMC as a monodentate through the carbonyl group, and DMF through the oxygen atom of the carbonyl group and the N atom of Py and Et₃N. The thermal behavior of the complexes was carefully investigated using TG and DTG techniques. TG findings signal that water molecules are found as hydrated and coordinated. The thermal decomposition mechanisms proposed for CIP, HMC, and Zr(IV) complexes are discussed and the activation energies (E_a), Gibbs free energies (∆G*), entropies (∆S*), and enthalpies (∆H*) of thermal decomposition reactions have been calculated using Coats–Redfern (CR) and Horowitz–Metzeger (HM) methods. The studied complexes were tested against some human pathogens and phytopathogens, including three Gram-positive bacteria (Bacillus subtilis, B. cereus, Brevibacterium otitidis) and three Gram-negative bacteria (Escherichiacoli, Pseudomonas aeruginosa and Klebsiella pneumoniae), and compared to the free CIP and HMC parent compounds. Full article

In this study, the antibacterial and antifungal properties of silver nanoparticles synthesized with the aqueous plant extract of Acer oblongifolium leaves were defined using a simplistic, environmentally friendly, reliable, and cost-effective method. The aqueous plant extract of Acer oblongifolium, which served as a capping and reducing agent, was used to biosynthesize silver nanoparticles. UV visible spectroscopy, X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), and scanning electron microscopy were used to analyze the biosynthesized Acer oblongifolium silver nanoparticles (AgNPs). Gram-positive bacteria (Bacillus paramycoides and Bacillus cereus) and Gram-negative bacteria (E. coli) were used to test the AgNPs’ antibacterial activity. The presence of different functional groups was determined by FTIR. The AgNPs were rod-like in shape. The nanoparticles were more toxic against Escherichiacoli than both Bacillus cereus and Bacillus paramycoides. The AgNPs had IC₅₀ values of 6.22 and 9.43 and mg/mL on HeLa and MCF-7, respectively, proving their comparatively strong potency against MCF-7. This confirmed that silver nanoparticles had strong antibacterial activity and antiproliferative ability against MCF-7 and HeLa cell lines. The mathematical modeling revealed that the pure nanoparticle had a high heat-absorbing capacity compared to the mixed nanoparticle. This research demonstrated that the biosynthesized Acer oblongifolium AgNPs could be used as an antioxidant, antibacterial, and anticancer agent in the future. Full article

The present study examined the effects of fructooligosaccharide (FOS) supplementation in drinking water on the growth performance, carcass characteristics, hematological and biochemical parameters, antioxidant status, and cecal microbiota of New Zealand White (NZW) and APRI rabbits. A total of 180 male NZW and APRI rabbits (aged five weeks; average live body weight 700 ± 39 g) were divided into six groups (30 rabbits/group; 5 replicates/group) in a two × three factorial arrangement. Rabbits of each breed were randomly assigned to one of three treatments of FOS (control; 0.00, FOS-0.5, and FOS-1.0). Results showed that rabbits’ final body weight, FBWG, and carcass traits were considerably enhanced compared to those in the control group. The interaction effect of the supplement with the rabbit breed increased the growth, carcass traits, and hematobiochemical and antioxidant parameters with increasing FOS levels. In the cecum of both rabbit breeds, the total bacterial count and Escherichiacoli population were considerably low, with a substantial increase in the number of Lactobacilli supplemented by FOS. In conclusion, FOS supplementation enhanced growth and carcass traits by improving the hematobiochemical parameters and antioxidant status and reducing cecal pathogenic bacteria in both breeds. Full article

The secondary metabolites of endemic plants from the Rutaceae family, such as Burkillanthusmalaccensis (Ridl.) Swingle from the rainforest of Malaysia, has not been studied. Burkillanthusmalaccensis (Ridl.) Swingle may produce antibacterial and antibiotic-potentiating secondary metabolites. Hexane, chloroform, and methanol extracts of leaves, bark, wood, pericarps, and endocarps were tested against bacteria by broth microdilution assay and their antibiotic-potentiating activities. Chromatographic separations of hexane extracts of seeds were conducted to investigate effective phytochemicals and their antibacterial activities. Molecular docking studies of werneria chromene and dihydroxyacidissiminol against SARS-CoV-2 virus infection were conducted using AutoDock Vina. The methanol extract of bark inhibited the growth of Staphylococcusaureus, Escherichiacoli, and Pseudomonasaeruginosa with the minimum inhibitory concentration of 250, 500, and 250 µg/mL, respectively. The chloroform extract of endocarps potentiated the activity of imipenem against imipenem-resistant Acinetobacterbaumannii. The hexane extract of seeds increased the sensitivity of P. aeruginosa against ciprofloxacin and levofloxacin. The hexane extract of seeds and chloroform extract of endocarps were chromatographed, yielding werneria chromene and dihydroxyacidissiminol. Werneria chromene was bacteriostatic for P.aeruginosa and P.putida, with MIC/MBC values of 1000 > 1000 µg/mL. Dihydroxyacidissiminol showed the predicted binding energies of −8.1, −7.6, −7.0, and −7.5 kcal/mol with cathepsin L, nsp13 helicase, SARS-CoV-2 main protease, and SARS-CoV-2 spike protein receptor-binding domain S-RBD. Burkillanthusmalaccensis (Ridl.) Swingle can be a potential source of natural products with antibiotic-potentiating activity and that are anti-SARS-CoV-2. Full article

Prochloraz (Pro) controlled-release nanoparticles (NPs) based on bimodal mesoporous silica (BMMs) with redox and pH dual responses were successfully prepared in this study. BMMs was modified by a silane coupling agent containing a disulfide bond, and β-cyclodextrin (β-CD) was grafted on the surface of the NPs through host–guest interaction. Pro was encapsulated into the pores of nanoparticles by physical adsorption. NPs had a spherical structure, and their average diameter was 546.4 ± 3.0 nm as measured by dynamic light scattering. The loading rate of Pro was 28.3%, and it achieved excellent pH/redox dual-responsive release performance under acidic conditions. Foliage adhesion tests on tomato leaves showed that the NPs had good adhesion properties compared to the commercial formulation. Owing to the protection of the nanocarrier, NPs became more stable under ultraviolet light and high temperature, which improves the efficient utilization of Pro. Biological activity tests showed that the NPs exhibited effective antifungal activity, and the benign biosafety of the nanocarrier was also observed through toxicology tests on cell viability and the growth of Escherichiacoli (E. coli). This work provides a promising approach to improving the efficient utilization of pesticides and reducing environmental pollution. Full article

Background: Endometritis is a common reproductive disease in equine animals. No investigation about the bacterial characteristics and antimicrobial susceptibility pattern of donkeys with endometritis has thus far been reported. Objectives: To determine the common uterine bacterial isolates from donkeys with endometritis and to evaluate their susceptibility to antimicrobials used for the treatment thereof. Study design: Retrospective case-series. Methods: Medical records at an equine clinical diagnostic center were retrospectively reviewed to identify submissions from donkeys with bacterial endometritis between 2018 and 2021. Data were extracted and analyzed descriptively in terms of the frequency of bacterial species, susceptibility to antimicrobials and multidrug resistance. Results: A total of 73 isolates were identified from 30 donkeys, of which 92% of the isolates were Gram-negative bacteria. Mixed cultures were found in 90% of the donkeys. The most common isolates were Escherichiacoli (31.5%) and Acinetobacter spp. (21.9%). Susceptibility testing revealed that amikacin (98%), cefoxitin (95%), trimethoprim-sulfamethoxazole (78%) and gentamicin (74%) were the most efficient agents for donkeys. Multidrug resistance (MDR) was found in 20% of all bacterial isolates, of which all Pseudomonas aeruginosa isolates showed a multidrug resistance profile. Main limitations: The sample size was relatively small, which means a bias of selection may exist. The antimicrobial resistance and MDR of agents without break points were not calculated, which means the relative results may be underestimated in our study. Conclusions: Severe infections were detected in donkeys with endometritis. Antimicrobial resistance and MDR bacteria are not rare in our study. This study demonstrated that bacteria identification and antimicrobial susceptibility testing are highly recommended before the treatment of uterine infections in donkeys. Further studies, including the epidemiological investigation of bacterial endometritis of donkeys, should be conducted to provide a better understanding of this critical problem. Full article