Metagenomic lactic acid bacterial diversity during Mulkimchi fermentation based on 16S rRNA sequence

Lactic acid bacterial diversity and the composition of individual bacterial communities during the fermentation of mulkimchi were examined using a polymerase chain recation (PCR)-based approach. Based on 16S rRNA sequence similarity values, a total of fifteen different lactic acid bacterial species were found in eight sampling sites, including Lactobacillus alimentarius, Lactobacillus brevis, Lactobacillus farciminis, Lactobacillus fabifermentans, Lactobacillus nantensis, Lactobacillus parabrevis, Lactobacillus plantarum, Lactobacillus versnoldensis, Lactobacillus zymae, and Lactobacillus sp., Leuconostoc pseudomesenteroides, Weissella cibaria, Weissella confusa, and Weissella sp. The prevalence of We. cibaria, belonging to the Weissella genus, was the highest (86.7%) at 0 h (initial stages) and gradually decreased at 72 h (rancid stage). In contrast, La. plantarum was observed at 36 h (16.7%, over-ripening stage) and gradually increased up to 84 h (70.0%, rancid stage) during mulkimchi fermentation. We. cibaria was found to be associated with the microorganisms that were present during the initial stage of fermentation, whereas La. plantarum was associated with the production of lactic acid in the over-ripening and rancid stages during fermentation at 30°C±2.