四川宜宾芽菜中乳酸菌分离筛选及菌相分析

Isolation, Selection and Analysis of Lactic Acid Bacteria (LAB) in Sichuan Yibin Pickled Mustard Vein

采用6种选择性培养基对宜宾芽菜中的乳酸菌进行分离纯化,通过pH值测定和乳酸定性,筛选出72h时pH值在4.0以下和产生乳酸与标样Rf值相近的菌株进行后续实验。采用16S rDNA PCR-RFLP、ERIC-PCR对筛选出的菌株进行遗传多样性分析,通过分析16S rDNA序列研究宜宾芽菜中乳酸菌菌相及其系统发育。16S rDNA PCR-RFLP和ERIC-PCR指纹图谱分析结果表明宜宾芽菜中乳酸菌遗传多样性丰富。根据16S rDNA PCR-RFLP和ERIC-PCR聚类图分析,选取中心菌株进行序列分析,并构建系统发育树,结果显示:宜宾芽菜中主要的乳酸菌为戊糖片球菌(Pediococcus pentosaceus)、植物乳杆菌(Lactobacillus plantarum)、坚强肠球菌(Eenterococcus durans)。

Six kinds of selective media were used to isolate lactic acid bacteria from Sichuan Yibin pickled mustard vein. The pH of the strain was lower more than 4.0 in MRS broth for 72 h cultivation and Rf value was similar to standard sample of lactic acid bacteria selected for follow-up tests. PCR-RFLP and ERIC-PCR of 16S rDNA were used to analyze the genetic diversity of strains. Sequence analysis of 16S rDNA was used to analyze the microflora and phylogeny of lactic acid bacteria in Yibin pickled mustard vein. PCR-RFLP and ERIC-PCR of 16S rDNA analysis showed that lactic acid bacteria were rich in genetic diversity. Based on the fingerprint of 16S rDNA PCR-RFLP and ERIC-PCR products, representative strains were selected to construct the phylogenetic tree and the results showed that the dominant lactic acid bacteria in Yibin pickled mustard vein were Pediococcus pentosaceus, Lactobacillus plantarum and Eenterococcus durans.