采用6种培养基对四川冬菜和发酵液中的产酸菌进行分离纯化,挑选出37株作为供试菌株。通过对37株菌株发酵产酸能力的测定、乳酸定性分析以及16S rDNA RCP-RFLP分析结果,最终选择17株菌株进行测序,并构建系统发育树。实验结果表明,所有供试菌株均有一定的产酸能力,其中大部分菌株产酸能力较好,且70%的菌株发酵过程中会产生乳酸。冬菜和发酵液中的产酸菌具有一定的多样性,主要为乳酸菌中的戊糖片球菌(Pediococcus pentosaceus)和肠球菌(Enterococcus)及普通细菌葡萄球菌(Staphylococcus)。另外,腌制时间对冬菜和发酵液中产酸菌的菌相组成影响很大,在腌制4年的冬菜(H)中还检测出与致病性溶血性葡萄球菌相似性很高的菌株,说明腌制时间过长的冬菜其品质难以保证。

Thirty-seven acid-producing bacterial strains were isolated from Sichuan Dongcai and its fermentation forth using 6 kinds of media. According to the production of acid,qualitative analysis of lactic acid and analysis of16S rDNA RCP-RFLP,seventeen isolates were selected to be sequenced and construct the phylogenetic tree. The results showed that all strains had a certain ability to produce acid,and the ability of producing acid of most strains was good,and 70% strains produced lactic acid in the fermentation process. There was a certain genetic diversity for the tested strains,and the dominant acid-producing bacteria in Sichuan Dongcai and its fermentation forth were Pediococcus pentosaceus,Enterococcus and staphylococcus. In addition,the fermentation time have a great influence on the microflora of acid-producing bacteria in Sichuan Dongcai and its fermentation forth. In the Dongcai fermented 4 years,Staphylococcus epidermidis was found,indicating that long curing time was difficult to guarantee the quality of Dongcai.