Lactobacillus paracasei from koumiss ameliorates diarrhea in mice via tight junctions modulation.

OBJECTIVES: Probiotics are gaining interest as alternative options for antibiotic or antiinflammatory drugs. Probiotics can affect the health of the host through metabolites and competitive inhibition adhesion of pathogenic microorganisms. Koumiss is an important part of the diet of Asian nomads, and is rich in a broad array of probiotics that can benefit the body. Mongolians have developed koumiss therapy to assist in the treatment of various diseases. In the present study, we investigate the beneficial effect of Lactobacillus paracasei, a strain isolated from koumiss, on a mouse model of diarrhea induced by Escherichia coli O8 (E. coli O8). METHODS: Probiotics were isolated from Mongolian koumiss. The resistance of probiotics against acid, bile salts, gastric juice, and intestinal juice was evaluated. The mouse model of diarrhea was established by the intragastric administration of E. coli O8 after NaHCO3 treatment. L. paracasei was intragastrically administered before or after E. coli O8 exposure in mice. The plasma levels of diamine oxidase and zounlin were quantified using an enzyme-linked immunosorbent assay, and the integrity of the intestinal barrier and goblet cells of mice with diarrhea were observed using hematoxylin and eosin and Alcian blue periodic acid-Schiff staining. The expression of tight junction (TJ) proteins was detected by immunohistochemistry and Western blot. RESULTS: A total of five lactic acid bacteria and two yeast strains were isolated from koumiss, and L. paracasei was screened for animal experiments. Experimental results showed that L. paracasei could reduce the increase in diamine oxidase and zonulin caused by E. coli (P < 0.05); increase goblet cells and the expression of TJ proteins ZO-1, occludin, and claudin-1 (P < 0.05); increase the expression of mucin 2, oligomeric mucus/gel-forming (P < 0.05) protein; and reduce the level of inhibitor kappa B-alpha and myosin light-chain kinase. CONCLUSIONS: L. paracasei reduced the intestinal permeability, induced the expression of mucin 2, oligomeric mucus/gel-forming protein, and increased the number of goblet cells in mice by the upregulation of the expression of TJ proteins via the nuclear factor kappa B cells-myosin light-chain kinase signaling pathway.

Study on the effect of koumiss on the intestinal microbiota of mice infected with Toxoplasma gondii.

Toxoplasma gondii is a worldwide food-borne parasite that can infect almost all warm-blooded animals, including humans. To date, there are no effective drugs to prevent or eradicate T. gondii infection. Recent studies have shown that probiotics could influence the relationship between the microbiota and parasites in the host. Koumiss has been used to treat many diseases based on its probiotic diversity. Therefore, we explored the effect of koumiss on T. gondii infection via its effect on the host intestinal microbiota. BALB/c mice were infected with T. gondii and treated with PBS, koumiss and mares' milk. Brain cysts were counted, and long-term changes in the microbiota and the effect of koumiss on gut microbiota were investigated with high-throughput sequencing technology. The results suggested that koumiss treatment significantly decreased the cyst counts in the brain (P < 0.05). Moreover, T. gondii infection changed the microbiota composition, and koumiss treatment increased the relative abundance of Lachnospiraceae and Akkermansia muciniphila, which were associated with preventing T. gondii infection. Moreover, koumiss could inhibit or ameliorate T. gondii infection by increasing the abundance of certain bacteria that control unique metabolic pathways. The study not only established a close interaction among the host, intracellular pathogens and intestinal microbiota but also provided a novel focus for drug development to prevent and eradicate T. gondii infection.

Antibacterial and antioxidant activity of exopolysaccharide mediated silver nanoparticle synthesized by Lactobacillus brevis isolated from Chinese koumiss.

Recently, silver nanoparticles gain significant attention due to their applications in various fields. The aim of present study was to develop the eco-friendly, cost effective, and simple method to biosynthesized the silver nanoparticle using sliver nitrate as precursor. In this study, we investigated the physical characterization and biotechnological applications of biosynthesized silver nanoparticle using exopolysaccharide of probiotic Lactobacillus brevis MSR104 isolated from Chinese koumiss. Biosynthesized silver nanoparticles were characterized using the fourier-transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, and elemental analyzer. The achieved results indicate that silver nanoparticles varied in sized with an average size of 45 nm. The X-ray diffraction analysis results showed that the silver nanoparticles have a crystalline nature. The results of antimicrobial assay indicated that the silver nanoparticles exhibited outstanding antimicrobial activity in dose dependent manner against both Gram's negative as well as Gram's positive. The antioxidant results indicate that the silver nanoparticles showed excellent scavenging rate against DPPH free radicals (81.4 ±â€¯1.2%) and nitric oxide free radicals (75.06 ±â€¯0.4%). Furthermore, the results of MTT assay revealed that the AgNPs significantly reduced the percentage of live HT-29 cells at higher concentration. This study concluded that the newly synthesized silver nanoparticles have antibacterial, antioxidant, and anticancer applications in agricultural and food industries.