저온발효 김치로부터 분리된 저온발육 유산균의 특성규명 및 안전성 평가

Abstract

In this study, low-temperature fermented kimchi was collected from nine regions in Korea. Storage temperature and aging period of product kimchi were analyzed and chemical properties were measured. DGGE profile was analyzed for 6 kinds of lactic acid bacteria(LAB) and 5 kinds of LAB isolated from low temperature kimchi. DGGE analysis was performed on the seven kimchi collected. Weissella koreensis and psychrotrophic Leuconostoc sp. band were observed in seven kimchi and Lactobacillus sakei band were observed in six kimchi. Fifteen kinds of psychrotrophic lactic acid bacteria were isolated and their characteristics were confirmed. Gram stain, catalase test, morphological observation and biochemical properties with API 50 CHL kit were performed. When 16S rRNA gene sequences of fifteen isolates were compared with type strains, one strain was identified as Leuconostoc carnosum NRIC 1722T, two as Leuconostoc inhae IH003T, and two as Lactobacillus algidus strain M 6 A9T, five as Leuconostoc gelidum subsp. aenigmaticum POUF4dT, five as Leuconostoc gelidum subsp. gasicomitatum strain TB 1-10T. The effect of initial temperature(5∼30℃) and initial pH(pH 4∼10) on LAB growth were confirmed for selected strains and they showed optimal growth ability at 15-25℃ and pH 7-9. Safety results, all of them didn't show α, β type hemolysis and harmful enzyme activity when tested by API zym kit. Thirteen strains showed antibiotic susceptibility lower than or equal to the breakpoint of EFSA(2012). The results of this study show that the characteristics of psychrotrophic LAB isolated from kimchi differ from mesophilic LAB and they are safe.