A high gamma-aminobutyric acid-producing Lactobacillus brevis isolated from Chinese traditional paocai

To find a high gamma-aminobutyric acid-producing lactic acid bacterium, more than 1000 strains of lactic acid bacteria isolated from paocai samples in various areas of China were screened by the ability in production of gamma-aminobutyric acid, analysed with paper chromatography, HPLC and HPLC-MS. Among them, one strain NCL912 exhibited high ability to convert sodium glutamate to gamma-aminobutyric acid. The strain accumulated 149.05 mM of gamma-aminobutyric acid in a modified MRS medium containing 3% sodium glutamate after 48 h of static cultivation at 30 degrees C. This strain was identified as Lactobacillus brevis according to its phenotypic and phylogenetic characteristics.