Application of Quantitative Real-Time PCR for Enumeration of Total Bacterial, Archaeal, and Yeast Populations in Kimchi
Eun-Jin Park, Ho-Won Chang, Kyoung-Ho Kim, Young-Do Nam, Seong Woon Roh, and Jin-Woo Bae*
Department of Life and Nanopharmaceutical Sciences and Department of Biology, Kyung Hee University, Seoul 130-701, Republic of Korea
Journal of Microbiology, 47(6),682-685, 2009,
quantitative PCR, kimchi, bacteria, archaea, yeast
Kimchi is a Korean traditional fermented food made of brined vegetables, with a variety of spices. Various microorganisms are associated with the kimchi fermentation process. This study was undertaken in order to apply quantitative real-time PCR targeting the 16S and 26S rRNA genes for the investigation of dynamics of bacterial, archaeal, and yeast communities during fermentation of various types of kimchi. Although the total bacterial and archaeal rRNA gene copy numbers increased during kimchi fermentation, the number of yeasts was not significantly altered. In 1 ng of bulk DNA, the mean number of rRNA gene copies for all strains of bacteria was 5.45×106 which was 360 and 50 times greater than those for archaea and yeast, respectively. The total gene copy number for each group of microorganisms differed among the different types of kimchi, although the relative ratios among them were similar. The common dominance of bacteria in the whole microbial communities of various types of kimchi suggests that bacteria play a principal role in the kimchi fermentation process.