Isolation and identification of lactic acid bacteria from Xiaoshan pickle radish, a traditional fermented vegetable

Abstract

The lactic acid bacterial fora during processing of Xiaoshan pickle radish were investigated. The samples were pickled with the product from three different markets by spontaneous fermentation. The average pH value varied from 6.8 ± 0.1 to 4.6 ± 0.2. There was no significant difference between the number of bacteria and pH value in samples from different product sites. A total of 387 gram-positive and catalase-negative isolates were obtained. All isolates were identified as Lactobacillus sakei and Leuconostoc lactis by physiological tests and 16S rRNA gene sequencing. Leuc. lactis was the dominated species in the initial stages of fermentation, but in late stages L. sakei had a remarkly increasing and the percentage were 0.0%, 16.7%, 50.0%, 81.8%, 80.0%, 83.3% and 100.0% respectively from stage "A"(before washing with clean water), "B" (after washing with clean water), "C" (before first curing), "D" (after first curing), "E" (before second curing), "F" (after second curing) to "G" (product ready-to-eat).