김치 유산균의 분리동정과 이용

초록

Lactic acid bacteria have been known to play important roles in the fermentation of kimchi. Identification of isolates from kimchi revealed that leuconostocs or lactobacilli are dominant species in kimchi. However, some previous classification of these isolates depended on classical classification methods including sugar-usage patterns. Therefore, we extensively identified bacterial isolates from kimchi using a polyphasic method including 16S rDNA sequencing, and found that Leuconostoc citreum or L. gelidum/ L. gascicomitatum are dominant species in the early stage of fermentation and Weissella species including W. hanii or Lactobacillus sake/ Lb. curvatus are successively dominant in the mid-stage of fermentation. Lactobacillus brevis appears as a spoilage organism at the later stage of fermentation. Meanwhile well-known L. mesenteroides is found as a minor group species in several different commercially available kimchi products as well as laboratory prepared kimchi. In this report we also discuss the effect of a starter on the fermentation of kimchi. A strain of Leuconostoc citreum isolated from kimchi was evaluated as a possible starter and this strain showed the ability that it could dominate over other natural microbial flora in kimchi and then extend the period of properly ripened stage, suggesting this strain can be used as starter culture to maintain the quality of kimchi for prolonged period.