维生素K2高产菌株的筛选与发酵条件优化  

Screening and Optimizing Fermentation Conditions of Bacillus Strain with High Productive Vitamin K2

作　　者：汤贵祥 陈朋友 包鑫 杨瑞丽 张慧莉[1] TANG Gui-xiang;CHEN Peng-you;BAO Xin;YANG Rui-li;ZHANG Hui-li(College of Life Science,Shihezi University,Shihezi 832003,China;Xinjiang Fufeng Biotechnology Co.,Ltd.,Urumqi 830001,China)

机构地区：[1]石河子大学生命科学学院,新疆石河子832003 [2]新疆阜丰生物科技有限公司,新疆乌鲁木齐830001

出　　处：《食品工业科技》2019年第24期68-73,共6页Science and Technology of Food Industry

基　　金：国家自然科学基金地区科学基金项目(21366028);博士后科学基金(2017M613301XB)

摘　　要：为了获得具有维生素K2(MK-7)合成能力的高产菌株,从富含芽孢杆菌的土壤中进行筛选,对获得的菌株进行16S rRNA序列及gyrB序列PCR扩增和比对,构建系统发育树后对其进行鉴定,并对发酵产物中的MK-7进行提取和分析,对其碳源、氮源和无机盐等发酵条件进行初步优化。结果表明,该菌株与解淀粉芽孢杆菌(Bacillus amyloliquefaciens)属于同一类群,其合成的MK-7大部分分泌到胞外。甘油是MK-7合成的最佳碳源,添加的最适浓度为5%;大豆蛋白胨最适浓度为12%。适当浓度的磷酸盐和金属离子Ca2+、Mg2+对MK-7合成有促进作用,添加的最适浓度分别是K2HPO4 0.7 g/L,CaCl2·2H2O 0.2 g/L,MgSO4·7H2O 0.5 g/L。利用优化后的培养基进行发酵培养,最终该菌株合成MK-7的最高产量达到70 mg/L以上。In order to obtain high-yield strain of synthesizing vitamin K2(MK-7),strains were screened from the soil riched in Bacillus,and was identified by sequence alignment of 16 S rRNA and the gyrB sequence amplified and blast by PCR. The phylogenetic trees was constructed and MK-7 from fermentation products of the stain was extracted and analyzed. Carbon,nitrogen and inorganic salts in the fermentation medium was also optimized. It was found that the microorganism belonged to the genus Bacillus amyloliquefaciens and most of synthesis MK-7 was secreted extracellularly. Glycerol was the best carbon source for MK-7 synthesis,and the optimum concentration was 5%. Soy peptone was the best nitrogen source,and the optimum concentration was 12%. Proper concentration of phosphate and metal ions(Ca2+ and Mg2+)could promote the synthesis of MK-7.The optimum concentration of inorganic salts for synthesis of MK-7 were 0.7 g/L(K2HPO4),0.2 g/L(CaCl2·2 H2O)and 0.5 g/L(MgSO4·7 H2O). By using the optimized medium,and the yield of MK-7 synthesized by the strain reached 70 mg/L or more.

关 键 词：维生素K2 甲萘醌 发酵 解淀粉芽孢杆菌 

分 类 号：TS201.3[轻工技术与工程—食品科学]