In vitro and in vivo examination of anticolonization of pathogens by Lactobacillus paracasei FJ861111.1

Abstract

Very limited information exists on the exclusion of pathogens by probiotics in the gut of the host challenged with pathogens. In this study, we tested probiotic characteristics in vitro and anticolonization ability of Lactobacillus paracasei FJ861111.1 in mice infected with selected pathogenic microorganisms. The in vitro results indicated that L. paracasei FJ861111.1 had a high survival in acidic conditions at pH 2.5 and bile salt concentration at 0.3%, and strong inhibition ability against common pathogens including Shigella dysenteriae, Staphylococcus aureus, Cronobacter sakazakii, Escherichia coli, and Candida albicans. The cell adhesion assays showed that L. paracasei FJ861111.1 exhibited strong adherence to HT-29 cells and excluded the adhesion of selected food-borne pathogens to HT-29 cells. The in vivo results showed that fermented milk with L. paracasei and viili (a Nordic yogurt product) significantly improved the population of total bacteria and of Lactobacillus in the feces of mice, and significantly inhibited the colonization of C. albicans to the intestines of mice post-C. albicans infection. Thus, it appears that this strain could be used as a probiotic organism for manufacturing functional fermented milk.

Probiotics for Prevention and Treatment of Candidiasis and Other Infectious Diseases: Lactobacillus spp. and Other Potential Bacterial Species

“…Deng et al [65] evaluated the probiotic action in vitro and the anticolonization capacity of L. paracasei FJ861111.1 in vivo in mice infected with other selected pathogenic microorganisms. In vitro results showed that Shigella dysenteriae, Staphylococcus aureus, Cronobacter sakazakii, E. coli, and C. albicans were inhibited by L. paracasei FJ861111.1 that presented elevated survival at pH 2.5 and bile salt concentration at 0.3%.…”

Evaluation of the potential of chicoric acid as a natural food antioxidant

“…The agar diffusion assay was performed to examine the anti-microbial activity of different concentrations of CA on Lactobacillus plantarum (isolated from human feces; State Key Laboratory of Food, Nanchang University, Nanchang, China), L. rhamnosus (Culturelle; i-Health, Inc., Cromwell, CT, USA), L. crispatus (isolated from vaginal secretion of women; Institute of Translational Medicine, Nanchang University) and Bifidobacterium longum isolated from a probiotic drug (Bifico; Shanghai Xinyi Pharmaceutical Factory Co., Ltd., Shanghai, China), as well as Salmonella enteritidis, Shigella typhimurium, Escherichia coli and Listeria monocytogenes (isolated from human feces; State Key Laboratory of Food, Nanchang University). The isolation of the microorganisms was performed as reported by previous studies by our group (15,(18)(19)(20)(21)(22). Cultures of the probiotics L. plantarum, L. rhamnosus, L. crispatus, B. longum grown anaerobically for 24 h in De Man, Rogosa and Sharpe medium (Oxoid Ltd; Thermo Fisher Scientific, Inc., Waltham, MA, USA) were centrifuged at 8,000 x g for 10 min at 4˚C to obtain supernatants.…”

Reclamation of Herb Residues Using Probiotics and Their Therapeutic Effect on Diarrhea

“…The bands of interest in DGGE gels were excised using a sterile blade and incubated overnight at 4°C in TE buffer (pH 8.0) to allow DNA diffusion for further amplifications. PCR products for sequencing were purified using the QIAquick PCR purification kit and subcloned using the pMD18-T vector system I (Takara) according to the manufacturer's instructions, and the transformants were randomly picked and sequenced by Invitrogen (Shanghai, China) [ 20 , 21 ].…”