2012 Volume 28 Issue 1 Pages 1-9
In our investigation of a variety of lactic acid bacteria in fermented foods in Thailand, we isolated 945 strains from 114 varieties of fermented foods from the northeastern, central, and southern parts of the northern Thailand. We determined their 16S ribosomal RNA (rRNA) gene sequences and selected 410 strains for further analyses based on differences of sequences and/or isolation source. The result of the 16S rRNA gene sequence analysis showed that the isolates were divided into 50 groups of six genera; Aerococcus, Enterococcus, Lactobacillus, Pediococcus, Tetragenococcus, and Weissella. Only one strain belonging to the genus Aerococcus showed 100% sequence similarity to A. viridans. Forty-six strains were assigned to the genus Enterococcus. They were divided into six groups to which they were closely related, namely, E. avium, E. faecalis, E. faecium, E. hirae, E. thailandicus, or E. gilvus/E. raffinosus. We sorted 309 strains belonging to the genus Lactobacillus into 34 sequence groups. Most of them showed a sequence that is 100% identical to those of known species. However, 12 strains of eight groups showed slightly lower similarity rates of lower than 99.0%, suggesting that they may be classified into novel species. Thirty-eight strains of three groups were classified in the genus Pediococcus. One group was closely related to P. acidilactici, and the other groups were closely related to P. pentosaceus. Four isolates were classified in Tetragenococcus halophilus. Twelve strains belonging to the genus Weissella were divided into five species, namely, W. cibaria, W. confusa, W. paramesenteroides, W. thailandensis, and W. viridescens. The strains isolated in this study will be available for public use in the BIOTEC Culture Collection and the NITE Biological Resource Center, with the numbers NBRC 107174 to 107352 and NBRC 108277 to 108549.
