Study on the effect of concurrent growth of some probiotics (Lactobacillus casei, Bifidobacterium angulatum and B.bifidum) and E.Coli in commercial sterilized milk

The purpose of this study was to investigate the effect of L. casei, B. angulatum and B. bifidum same-time growth of probiotics L. casei, B. angulatum and B. bifidum with E.coli in commercial sterilized milk to evaluate the provisional effects of probiotics on E.coli food-borneinfection in human. At first one ml of solution containing 1.5×108 of activated E.coli was added to 400 ml of sterilized milk 1.5% fat and after homogenization it was divided equally in four parts. The first parts was considered as individual culture and the other parts recieved one ml of solution containing of 1.5×108 of the above probiotics respectively. After 24 hours of incubation at 37 °C, pH and the number of E.coli per ml was counted using pour plate method in VRBA medium. This procedure was repeated 10 times and the mean of pH and number of E.coli in individual culture and experimental cultures were compared. The results indicated that L.casei and B.angulatum significantly canreduce the growth rate of E.coli (P0.05). Thus the consumption of products containing L.casei and B.angulatum could be prevent some E.coli infection, however further information respect to invivo experiments should be gathered.