Pyrosequencing analysis of microbiota reveals that lactic acid bacteria are dominant in Korean flat fish fermented food, gajami-sikhae.

The gajami-sikhae, traditional Korean cuisine fermented with flat fish, samples were collected from eight different manufacturers (GS1-GS8). We employed pyrosequencing method to analyze the bacterial communities of the gajami-sikhae samples. Family- and genus-level analyses indicated that the bacterial community compositions of GS3 and GS6 were distinct from those of the rest. The species-level structures of bacterial communities of the gajami-sikhae samples except for GS3 and GS6 featured Lactobacillus sakei as the most abundant species. Leuconostoc mesenteroides was revealed as the most dominant species among the bacterial community of GS6 and the bacterial community of GS3 was composed of various lactic acid bacteria. We employed a culture-based method to isolate beneficial strains from the gajami-sikhae samples. However, most of the 47 selected colonies were identified as Bacillus subtilis and Bacillus amyloliquefaciens. This study indicated that gajami-sikhae was mainly composed of many beneficial lactic acid bacteria.