[Intervention effect of probiotic bifidobacterium on type 2 diabetes mellitus rats].

OBJECTIVE: To observe the influences of bifidobacterium on glucose and lipid metabolism and intestinal flora in type 2 diabetes mellitus rats. METHODS: Rats were randomly divided into 4 groups, the blank control group was fed with basic forage, the other 3 groups were fed with high fat diet. Meanwhile the high-dose and low-dose groups were gavage administrated with 12 and 4 ml/(kg x d) probiotic bifidobacterium for 6 weeks, then, injected with low dose of streptozotocin (20 mg/kg). All rats were sacrificed 2 weeks later, blood and feces samples were collected to analyse. RESULTS: Compared with rats of type 2 diabetes model, glucose concentrations and serum concentrations of FFA, TG, LDL-C of 2 experimental groups were significantly lower, serum concentrations of HDL-C were higher, insulin sensitivity index was higher, content of bifidobacterium was higher, but there were no significant differences in other 5 bacteria. CONCLUSION: The probiotic bifidobacterium could significantly ameliorate the disorder of glucose and lipid metabolism, increase the amount of bifidobacterium of type 2 diabetes rats.

Lactococcus lactis expressing food-grade ß-galactosidase alleviates lactose intolerance symptoms in post-weaning Balb/c mice.

The endogenous ß-galactosidase expressed in intestinal microbes is demonstrated to help humans in lactose usage, and treatment associated with the promotion of beneficial microorganism in the gut is correlated with lactose tolerance. From this point, a kind of recombinant live ß-galactosidase delivery system using food-grade protein expression techniques and selected probiotics as vehicle was promoted by us for the purpose of application in lactose intolerance subjects. Previously, a recombinant Lactococcus lactis MG1363 strain expressing food-grade ß-galactosidase, the L. lactis MG1363/FGZW, was successfully constructed and evaluated in vitro. This study was conducted to in vivo evaluate its efficacy on alleviating lactose intolerance symptoms in post-weaning Balb/c mice, which were orally administered with 1 × 106 CFU or 1 × 108 CFU of L. lactis MG1363/FGZW daily for 4 weeks before lactose challenge. In comparison with naïve mice, the mice administered with L. lactis MG1363/FGZW showed significant alleviation of diarrhea symptoms in less total feces weight within 6 h post-challenge and suppressed intestinal motility after lactose challenge, although there was no significant increase of ß-galactosidase activity in small intestine. The alleviation also correlated with higher species abundance, more Bifidobacterium colonization, and stronger colonization resistance in mice intestinal microflora. Therefore, this recombinant L. lactis strain effectively alleviated diarrhea symptom induced by lactose uptake in lactose intolerance model mice with the probable mechanism of promotion of lactic acid bacteria to differentiate and predominantly colonize in gut microbial community, thus making it a promising probiotic for lactose intolerance subjects.

[The relationship between esp and the ability of biofilm formation in enterococci from the intestinal tract of normal people].

OBJECTIVE: To investigate the biofilm formation of Enterococci from the intestinal tract of normal people, to study the relationship between esp and the ability of biofilm formation in Enterococci. METHODS: PCR was applied to detect the esp gene in 84 isolates. And the biofilm formation was performed in 96 well polystyrene plates. RESULTS: The detection rate of esp in Enterococci was 14.3%, the rate of biofilm formation was 25.0%, the rate of biofilm formation of esp positive isolates was 83.3%, and that of esp negative isolates was 15.3%. CONCLUSION: Biofilm formation is not very common in Enterococci from the intestinal tract of normal people, esp is an important factor of biofilm formation, and the ability of biofilm formation is not limited to the esp positive isolates.