两种益生菌发酵促使牛骨粉中钙转化的比较研究

选用鼠李糖乳杆菌、婴儿双歧杆菌发酵牛骨粉。采用L9(34)正交试验设计，对蔗糖添加量、接种量、骨粉浓度、发酵时间进行筛选。以游离钙转化率为特征性指标探讨发酵条件对游离钙转化率影响的变化规律，并且比较两种益生菌在体外模拟胃肠环境中的活菌数。结果表明：鼠李糖乳杆菌的最适发酵条件为蔗糖添加量11%、接种量3%、骨粉浓度5g/100ml、发酵时间72h，婴儿双歧杆菌的最适发酵条件为蔗糖添加量8%，接种量5%、骨粉浓度10g/100ml、发酵时间72h；鼠李糖乳杆菌对牛骨粉中钙的转化率达32.0%，约为婴儿双歧杆菌的3倍；发酵时间是影响游离钙转化率的重要因素；鼠李糖乳杆菌活在模拟胃、肠液中的菌率是分别婴儿双歧杆菌的10.38、16.35倍。

Comparative Study on Calcium Transformation in Cattle Bone Powder by Fermentation of Lctobacillus rhamnosus GG and Bifidobacterium infantis

In order to promote the transformation of bound calcium into free form, cattle bone powder was fermented with Lactobacillus rhamnosus GG and Bifidobacterium infantis, respectively. A L9 (34) orthogonal test was designed to optimize the fermentation conditions of the above two probiotics, such as amount of added sugar, inoculation amount, bone powder concentration and fermentation time with calcium transformation rate as the main evaluation index. In addition, the survival rates of the two probiotics in simulated gastric juice and intestinal juice were compared respectively. Results indicated that the optimal fermentation conditions of cattle bone powder by Lactobacillus rhamnosus GG were as follows: amount of added sugar 11%, inoculation amount 3%, bone powder concentration 5 g/100 ml and fermentation time 72 h (the most significant affecting factor), and those by Bifidobacterium infantis were as follows: amount of added sugar 8%, inoculation amount 5% (the most significant affecting factor), bone powder concentration 10 g/100 ml and fermentation time 72 h. The calcium transformation rate by Lactobacillus rhamnosus GG fermentation was up to 32%, which was about 3 times as much as that by Bifidobacterium infantis fermentation. The survival rates of Lactobacillus rhamnosus GG in simulated gastric juice and intestinal juice were 10.38 and 16.35 times of those of Bifidobacterium infantis in the above two simulated juices, respectively.