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Piper betle leaves have traditionally been used to treat many diseases, including bacterial infections. The present study aimed to investigate the antibacterial, antibio lm, and anti-adhesion activities of P. betle extract against Avian pathogenic Escherichia coli (APEC). The ethanol extract of P. betle leaves demonstrated strong antibacterial activity against clinical isolates of APEC with MIC and MBC values ranging from 0.5-1.0 mg/mL. Disruption and breakdown of the bacterial cells were detected when the cells were challenged with the extract at 2×MIC. Bacterial cells treated with the extract demonstrated longer cells without a septum, compared to the control. The extract at 1/8, 1/4, and 1/2×MIC signi cantly inhibited the formation of bacterial bio lm of the isolates (P<0.05) without inhibiting growth. At 1/2×MIC, 55% of the bio lm inhibition was detected in APEC CH09, a strong bio lm producer. At 32×MIC, 88% of the inhibition of viable cells embedded in the mature bio lm was detected in APEC CH09. Reduction in the bacterial adhesion to surfaces was shown when APEC were treated with sub-MICs of the extract as observed by SEM. The results suggested potential medicinal bene ts of P. betle extract for the treatment of the infection caused by Avian pathogenic E. coli.

Curcuma longa and Curcumin have been documented to have a wide spectrum of pharmacological effects, including anti- Acanthamoeba activity. Hence, this study sought to explore the anti-adhesion activity of C. longa extract and Curcumin against Acanthamoeba triangularis trophozoites and cysts in plastic and contact lenses. Our results showed that C. longa extract and Curcumin significantly inhibited the adhesion of A. triangularis trophozoites and cysts to the plastic surface, as investigated by the crystal violet assay (P < 0.05). Also, an 80–90% decrease in adhesion of trophozoites and cysts to the plastic surface was detected following the treatment with C. longa extract and Curcumin at 1/2 × MIC, compared to the control. In the contact lens model, approximately 1 log cells/mL of the trophozoites and cysts was reduced when the cells were treated with Curcumin, when compared to the control. Pre-treatment of the plastic surface with Curcumin at 1/2-MIC reduced 60% and 90% of the adhesion of trophozoites and cysts, respectively. The reduction in 1 Log cells/mL of the adhesion of A. triangularis trophozoites was observed when lenses were pre-treated with both the extract and Curcumin. Base on the results obtained from this study, A. triangularis trophozoites treated with C. longa extract and Curcumin have lost strong acanthopodia, thorn-like projection pseudopodia observed by scanning electron microscope. This study also revealed the therapeutic potentials of C. longa extract and Curcumin, as such, have promising anti-adhesive potential that can be used in the management/prevention of A. triangularis adhesion to contact lenses.

Background Probiotics can release bioactive substances known as postbiotics, which can inhibit pathogenic microorganisms, improve immunomodulation, reduce antioxidant production, and modulate the gut microbiota. Methods In this study, we evaluated the in vitro antimicrobial effects, antioxidant activity, and anti-inflammatory potential of 10 lyophilized cell-free supernatants (LCFS) of Lactobacillus isolates. LCFS was obtained via centrifugation and subsequent lyophilization of the supernatant collected from the culture medium ofeach isolate. The antibacterial and antibiofilm activities of the LCFS were determined using broth microdilution. The antioxidant potential was evaluated by measuring the total phenolic and flavonoid contents and 2,2-Diphennyl-1-picrylhydrazyl (DPPH) and 2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical cation (ABTS+) radical scavenging activities. Results All the isolates were able to inhibit the four tested pathogens. The isolates exhibited strong antibiofilm activity and eradicated the biofilms formed by Acinetobacter buamannii and Escherichia coli. All the prepared Lactobacillus LCFS contained phenols and flavonoids and exhibited antioxidant activities in the DPPH and ABTS+ radical scavenging assays. The MTT (3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide) assay revealed that LCFS was not cytotoxic to RAW 264.7 cells. In addition, the ten Lactobacillus LCFS decreased the production of nitric oxide. Conclusions All the isolates have beneficial properties. This research sheds light on the role of postbiotics in functional fermented foods and pharmaceutical products. Further research to elucidate the precise molecular mechanisms of action of probiotics is warranted.

Malaria is still a serious cause of mortality and morbidity. Moreover, the emergence of malaria parasite resistance to antimalarial drugs has prompted the search for new, effective, and safe antimalarial agents. For this reason, the study of medicinal plants in discovering new antimalarial drugs is important and remains a crucial step in the fight against malaria. Hence, this study is aimed at investigating the antimalarial activity of Gymnema inodorum leaf extract (GIE) in Plasmodium berghei infected mice. Aqueous crude extract of G. inodorum leaves was prepared in distilled water (DW) and acute toxicity in mice was carried out. The antimalarial activity was assessed in the five groups of ICR mice employing the 4-day suppressive and curative tests. Untreated and positive controls were given DW along with 10 mg/kg of chloroquine, respectively. Any signs of toxicity, behavioral changes, and mortality were not observed in mice given GIE up to 5,000 mg/kg. GIE significantly ( P  < 0.05) suppressed parasitemia by 25.65%, 38.12%, and 58.28% at 10, 50, and 100 mg/kg, respectively, in the 4-day suppressive test. In the curative test, the highest parasitemia inhibition of 66.78% was observed at 100 mg/kg of GIE. Moreover, GIE prevented packed cell volume reduction and body weight loss compared to the untreated control. Additionally, GIE was able to prolong the mean survival time of infected mice significantly. The results obtained in this study confirmed the safety and promise of G. inodorum as an important source of new antimalarial agents and justify its folkloric use for malaria treatment.

Clostridioides (Clostridium) difficile infection is implicated as a major cause of antibiotic-associated diarrhea in hospitals worldwide. Probiotics, especially lactic acid bacteria, are the most frequently used alternative treatment. This study aims to identify potential probiotic enterococci strains that act against C. difficile strains and exert a protective effect on colon adenocarcinoma cells (HT-29 cells). To this end, nine Enterococcus strains isolated from the feces of breast-fed infants were investigated. They were identified as E. faecalis by 16s rRNA sequencing and MALDI-TOF. The probiotic properties including their viabilities in simulated gastrointestinal condition, cell adhesion ability, and their safety were evaluated. All strains exhibited more tolerance toward both pepsin and bile salts and adhered more tightly to HT-29 cells compared with the reference probiotic strain Lactobacillus plantarum ATCC 14917. Polymerase chain reaction (PCR) results exhibited that six of nine strains carried at least one virulence determinant gene; however, none exhibited virulence phenotypes or carried transferable antibiotic resistance genes. These strains did not infect Galleria mellonella when compared to pathogenic E. faecalis strain (p < 0.05). Moreover, their antibacterial activities against C. difficile were examined using agar well-diffusion, spore production, and germination tests. The six safe strains inhibited spore germination (100-98.20% ± 2.17%) and sporulation, particularly in C. difficile ATCC 630 treated with E. faecalis PK 1302. Furthermore, immunofluorescence assay showed that the cytopathic effects of C. difficile of HT-29 cells were reduced by the treatment with the cell-free supernatant of E. faecalis strains. These strains prevented rounding of HT-29 cells and preserved the F-actin microstructure and tight junctions between adjacent cells, which indicated their ability to reduce the clostridial cytopathic effects. Thus, the study identified six E. faecalis isolates that have anti-C. difficile activity. These could be promising probiotics with potential applications in the prevention of C. difficile colonization and treatment of C. difficile infection.

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Background The increasing prevalence of broad-spectrum ampicillin-resistant and third-generation cephalosporin-resistant Enterobacteriaceae, particularly Escherichia coli and Klebsiella pneumoniae, has become a global concern, with its clinical impacts on both human and veterinary medicine. This study examined the prevalence, antimicrobial susceptibility, and molecular genetic features of extended-spectrum β-lactamase (ESBL)-producing E. coli and K. pneumoniae isolates from 10 types of raw vegetables. Methods In total, 305 samples were collected from 9 markets in Nakhon Si Thammarat, Thailand, in 2020. Results ESBL-producing E. coli and K. pneumoniae isolates were found in 14 of the 305 samples obtained from 7 out of 10 types of vegetables (4.6% of the total). Further, 14 ESBL-producing E. coli (n = 5/14) and K. pneumoniae isolates (n = 9/14) (1.6% and 3.0%, respectively) were highly sensitive to β-lactam/carbapenem antibiotics (imipenem, 100%). ESBL-producing E. coli (n = 4) and K. pneumoniae isolates (n = 8) were also sensitive to non-β-lactam aminoglycosides (amikacin, 80.00% and 88.89%, respectively). ESBL producers were most resistant to β-lactam antibiotics, including ampicillin (85.71%) and the cephalosporins cefotaxime and ceftazidime (64.29%). The most frequently detected gene in ESBL-producing E. coli and K. pneumoniae was blaSHV. However, two ESBL-producing E. coli isolates also carried three other ESBL-encoding variants, blaTEM, blaCTX-M1, blaGES and blaTEM, blaSHV, blaCTX-M9, which may be due to their association with food chains and humans. Discussion Indeed, our results suggest that raw vegetables are an important source of ESBL-resistant E. coli and K. pneumoniae, which are potentially transmittable to humans via raw vegetable intake.