Abstract: In order to broaden and evaluate microbial resources for producing γ-aminobutyric acid (GABA), lactic acid bacteria and yeast strains with the ability to produce GABA were isolated, screened and identified from Sichuan pickles. A total of 338 strains of lactic acid bacteria and 67 strains of yeast were initially isolated from Sichuan pickles. Further, 12 strains of lactic acid bacteria (LAB) and 3 strains of yeast which could produce GABA were screened out by paper chromatography. Then the 12 LAB strains were identified as Lactobacillus acidophilus (8.3%), Lactobacillus fermentum (8.3%), Lactobacillus kimchii (8.3%), Lactobacillus suebicus (8.3%), Lactobacillus longer (16.7%), Lactobacillus parafarraginis (8.3%), Lactobacillus similis (8.3%), Lactobacillus plantarum (25.2%) and Lactobacillus pentosus (8.3%), while the 3 yeast strains were identified as two strains of Saccharomyces cerevisiae and one strain of Candida tanzawaensis using physiological and biochemical tests and phylogenetic analysis. The GABA-producing ability of these selected strains was further assessed by high-performance liquid chromatography (HPLC). Our results indicated that Lactobacillus plantarum BC114, Lactobacillus brevis BC237 and Saccharomyces cerevisiae JM037 showed higher GABA-producing capability, and the cultured broth supernatants contained 1 720, 1 080 and 670 mg/L GABA, respectively.

Key words: γ-aminobutyric acid, Sichuan pickles, microorganism, phylogeny, performance assessment