产胞外多糖罗汉果内生菌的筛选及其发酵条件优化  

Screening of extracellular polysaccharide-producing strains from endophytic bacteria of Siraitia grosvenorii and fermentation conditions optimization

作　　者：王琪 付强 周巧丽 金岳 胡梦琪 赵丰丽[1,2] WANG Qi;FU Qiang;ZHOU Qiaoli;JIN Yue;HU Mengqi;ZHAO Fengli(College of Life Science,Guangxi Normal University,Guilin 541006,China;Key Laboratory of Ecology of Rare andEndangered Species and Environmental Protection,Ministry of Education,Guilin 541006,China)

机构地区：[1]广西师范大学生命科学学院,广西桂林541006 [2]珍稀濒危动植物生态与环境保护教育部重点实验室,广西桂林541006

出　　处：《中国酿造》2021年第7期89-93,共5页China Brewing

基　　金：桂林市科学研究与技术开发计划项目(20171015-2)。

摘　　要：该研究利用α-萘酚-硫酸法和苯酚-硫酸法从罗汉果中筛选产胞外多糖的内生菌株,采用形态观察、生理生化试验及分子生物学技术对其进行菌种鉴定,并采用单因素和正交试验对其产胞外多糖的发酵条件进行优化。结果表明,筛选到一株产胞外多糖的罗汉果内生菌株,编号为LHG-3,并被鉴定为韦德曼尼芽孢杆菌(Bacillus wiedmannii)。菌株LHG-3产胞外多糖的最佳培养基为超级肉汤(TB)培养基,在此基础上,经优化得出最优发酵条件为蔗糖2.5%、尿素1.2%、氯化钙0.4%、pH值7.0、接种量8%,在30℃条件下培养42 h后,胞外多糖产量达到(1.59±0.03)mg/mL,是优化前的1.9倍。In this study,the extracellular polysaccharide-producing endophyte was screened from Siraitia grosvenorii by α-naphthol-sulfuric acid method and phenol-sulfuric acid method,and identified by morphological observation,physiological and biochemical tests and molecular biology techniques.The fermentation conditions for the extracellular polysaccharide-producing strain were optimized by single factor and orthogonal experiments.The results showed that a extracellular polysaccharide-producing endophyte was screened,named LHG-3,and identified as Bacillus wiedmannii.The optimal medium for the strain LHG-3 was terrific broth(TB)medium.Based on this,the optimum conditions were sucrose 2.5%,urea 1.2%,calcium chloride 0.4%,pH 7.0 and inoculum 8%.The production of extracellular polysaccharide reached(1.59±0.03)mg/ml at 30℃for 42 h,which was 1.9 times higher than that before optimization.

关 键 词：罗汉果 内生菌 筛选 鉴定 胞外多糖 发酵条件优化 

分 类 号：Q939.9[生物学—微生物学]