泡菜中亚硝酸盐形成、还原相关微生物的研究

Study on Microorganisms Related to Nitrite Formation and Reduction in Pickles

针对甘蓝发酵过程中亚硝酸盐含量异常增多的普遍现象开展甘蓝发酵体系中亚硝酸盐形成、还原微生物鉴定的研究。利用PCR-DGGE-克隆的非培养方法分析甘蓝发酵过程中细菌、真菌随发酵时间变化而演变的规律。根据DGGE电泳图谱中的相对含量(由凝胶成像系统的配套软件Quantity-One计算强度)做出随发酵时间的变化图。并和NO2-含量随发酵时间变化图相比较,推测与NO2-形成、还原相关优势微生物的基因片段,分析优势微生物变化与亚硝酸盐含量变化的关系。通过对比测序确定微生物种属得出:与亚硝酸盐形成相关的微生物主要是肠杆菌(Enterobacteriaceae bacterium)、松鼠葡萄球菌(Staphylococcus sciuri)、假单胞菌(Pseudomonas sp.)、泛菌(Pantoea dispersa)、假丝酵母(Candida saitoana)、德巴利氏酵母(Debaryomyces occidentalis)、毕赤酵母(Pichia sorbitophila)。与亚硝酸盐还原相关的微生物为柠檬明串珠菌(Leuconostoc citreum)和明串珠菌(Leuconostoc citreumstrain)。

In view of the common phenomenon of abnormal increase of nitrite content in cabbage fermentation process,the research on nitrite formation and microbial identification in cabbage fermentation system is carried out.The non-culture method of PCR-DGGE-clone is used to analyze the evolution of bacteria and fungi in cabbage fermentation process with fermentation time.According to the relative content in DGGE electrophoretogram(the intensity is calculated by the matching software Quantity-One of gel imaging system),the change chart with fermentation time is made.Compared with the changes of NO2-content with fermentation time,the gene fragments of dominant microorganisms related to the formation and reduction of NO2-are speculated and the relationship between the change of dominant microorganisms and the change of nitrite content is analyzed.The microbial species are determined by comparative sequencing as follows:the microorganisms associated with nitrite formation mainly are Enterobacteriaceae bacterium,Staphylococcus sciuri,Pseudomonas sp.,Pantoea dispersa,Candida saitoana,Debaryomyces occidentalis,Pichia sorbitophila;the microorganisms associated with nitrite reduction are Leuconostoc citreumand Leuconostoc citreumstrain.