| Abstrakt: |
The aim of this study consist to isolate and identify stocks of the Lactobacillus genre starting from ewe , goat and cow's milk collected starting from the area of chlef, and the study of their antimicrobial effects against E.coli ATCC 25922 responsible of infantile diarrheas and the study of their survive in a media similar to the conditions of the digestive tract. 32 isolats of Lactobacillus among 80 were characterized, they are sticks gram positive, negative catalase and push in anaerobiosis and i n a slightly acid media. The interaction between the lactic strains and E.coli present a significant activity. The strains retained for their inhibiting effect are: Lb33, Lb31, Lb58, Lb63, Lb64 whose diameter of inhibition was between 7 mm and 17 mm. The study of the survive of these strains shows that five (Lb33, Lb31, Lb 58, Lb64, Lb63) have a good resistance with respect to extreme conditions of the digestive tract (gastric acidity and bile salts). the viable rate of bacteries is remarkable to deferent pH (2.5, 4.5 and 6.5) in absence and in presence of bile salts; they arrive at 10 9 UFC/ml after 6h and at 10 7 UFC/mL after 72h of incubation at 37°C. The biochemical identification shows that the strains Lb33 and Lb31 belong Lactobacillus plantarum, Lb58 is Lactobacillus rhamnosus , Lb63 and Lb64 are Lactobacillus casei. According to our study, we can deduce that our strainss can be regarded as the probiotic one for the prevention of the infantile diarrheas. In prospect we hope for acontinuity of this work by applying these results in vivo. [ABSTRACT FROM AUTHOR] |
