鼠李糖乳杆菌发酵豆渣、黄浆水产L-乳酸工艺优化

Optimizating the Fermentation Techniques of Bean Dregs and Yellow Serofluid by LGG to Produce L-lactic Acid

为了提高发酵基质中LGG的活菌数及L-乳酸产率,以豆渣和黄浆水为培养基质,选用生长条件粗放、仅产L-乳酸的鼠李糖乳杆菌为发酵菌株,添加促生因子以提高L-乳酸产率。通过单因素试验设计,以L-乳酸含量为特征指标,筛选能够促进鼠李糖乳杆菌生长、提高L-乳酸含量的促生因子及豆渣与黄浆水的最佳比例。采用响应面设计优化鼠李糖乳杆菌发酵豆渣和黄浆水产L-乳酸工艺条件。结果表明,在豆渣与黄浆水以1∶4.80为基础培养基,添加0.06%烟酸、1%精氨酸和蛋氨酸(m精氨酸:m蛋氨酸=2.21∶1)、6%葡萄糖和低聚果糖(m葡萄糖:m低聚果糖=1.57∶1),接种量3%,pH 6.2,37℃,发酵72h的条件下L-乳酸含量为2.35%。

Utilizing the bean dregs and yellow serofluid as media,Lactobacillus rhamnosus which could extensively grow and only produce L-lactic acid was used as fermentation strain,and growth-promoting factors were added to improve the productivity of L-lactic acid.Through the single factor experiment design,the L-lactic acid content was used as the characteristic index to select growth-promoting factors and ratio of bean dregs and yellow serofluid.Response surface design was adopted to optimize fermentation conditions.The results showed that the optimal formula technique was ratio of bean dregs and yellow serofluid as 1∶4.80 as basic culture media,adding 0.06% niacin,1% arginine and methionine （marginine∶mmethionine =2.21 ∶ 1）,6 % （mglucose ∶ mfructooligosaccharide =1.57 ∶ 1）,3 % of inoculation amount,pH 6.2,72h of fermentation time,and 37℃,under this cultural condition,L-lactic acid content could be readed to 2.35%.