Culture-dependent and culture-independent analysis of lactic acid bacteria from Shanxi aged vinegar

Abstract

Shanxi aged vinegar, one of the traditional Chinese vinegars, is brewed by spontaneous fermentation with various microorganisms involved. The previous study showed that lactic acid bacteria (LAB) was the main bacteria population during the conversation period of starch to ethanol of the production. Here, culture-dependent and -independent methods were applied to study the diversity of the LAB population in the fermentation process of Shanxi aged vinegar. Isolates with various genotypic characters were screened and selected based on enterobacterial repetitive intergenic consensus/PCR (ERIC/PCR) fingerprinting. PCR-restriction fragment length polymorphism analysis combined with 16S rDNA sequencing identification revealed that seven species including Lactobacillus fermentum, L. plantarum, L. casei, L. buchneri, Pediococcus acidilactici, P. pentosaceus and Weissella confusa were recovered. DNA extracted directly from fermenting samples was separated by the PCR-denaturing gradient gel electrophoresis, which indicated that the main species presented in the period of starch changed into ethanol were L. fermentum, Leuconostoc mesenteroides and W. confusa.