一株产L-乳酸菌株的筛选、鉴定及营养条件的初步研究

Screening,Identification of a Bacteria Strain for the Production of L-lactic Acid

作者对筛选的一株产L-乳酸的菌株进行了菌种鉴定,根据16S rDNA序列测定结果,结合其形态特征及生理生化性质,确定该菌株为凝结芽孢杆菌(Bacillus coagulans)。进一步对其营养条件进行了研究,初步确定玉米糖化液为最适碳源,采用1g/dL酵母粉与1g/dL棉籽蛋白的混合氮源,L-乳酸产量不仅有所提高且成本大大降低,金属离子Mn2+、Fe2+、Mg2+都可在一定程度上提高L-乳酸的产量。

A bacteria strain was isolated and identified for L-lactic acid production in this study,The isolated strain was identified as Bacillus coagulans based on the results of 16S rDNA,the physiological characteristics and the biochemical properties.Then the optimum nutrient conditions was determined by the single factor experiments and list as fellows：10.5 g/dL corn syrup,1 g/dL yeast extract,1 g/dL cotton-seed protein.Furthermore,it was found that the presence of Mn2＋、Fe2＋ and Mg2＋ in the medium can enhance L-lactic acid production.