Studes On Promoting Medium Of Lactobacillus Acidophilus

As one kind of probiotic bacteria, Lactobacillus acidophilus has its important function on the host for its health benefit and prophylaxis disease, and it has become a hot subject in the field of dairy science.For Lactobacillus acidophilus, either the exploiture of biological preparation, or isolation and cultivating on Lactobacillus acidophilus, zymology research, preparation of starter, all research need eximious enrichment medium that can greatly promote the growth of Lactobacillus acidophilus. Therefore, the optimizing Lactobacillus acidophilus culture is an extremely basic research work.In order to guaranteen a high viable counts of the probiotic bacteria, we must optimize the following aspects: choosing appropriate bacterium, improving its living condition, and adding growth promoting factors and so on. In this subject, based on tolerant ability to pH and bile salts, inhibition ability to microorganism in human intestinal, and growth power and acid- producing ability, three Lactobacillus acidophilus was compared, and the best strain was choosen. According to the growth metabolism and the nutrition demand of Lactobacillus acidophilus, MRS was selected as the basic medium. On the basis of MRS, seven nutriments including inulin, lactose, whey powder, casein peptone hydrolysate, tomato juice, carrot juice was added to MRS separately, at three level, the influence of Lactobacillus acidophilus growth was studied, thus the optimum performance on strain's growth and the best adding quantity of each nutriments was determined. The growth promoting performance of seven factors was compared, the result shows: seven factors'optimum adding quantity is as follows: inulin(instead of 50% glucose in MRS), 0.5% lactose, 1.8% whey powder, 0.9% casein peptone hydrolysate, 15% tomato juice, 12% carrot juice, 15% beer. And the comparation result shows that adding inulin, whey powder, casein peptone hydrolsate and carrot juice can prmote the growth of Lactobacillus acidophilus evidently, but adding lactose, tomato juice and beer exerted insignificantly effects on the growth of Lactobacillus acidophilus. The promoting medium of Lactobacillus acidophilus was optimized by orthogonality test, the result shows: the optimal medium consisted of 1.5% of whey powder hydrolysate, 1.2% of...