Abstract:

The aim of the present study was to investigate the optimization of formulation of culture medium for γ-aminobutyric
acid (GABA)-producing lactic acid bacteria. The effects of carbon sources, nitrogen sources, K2HPO4, Tween-80 and monosodium
L-glutamate (L-MSG) on the growth of L. plantarum MJ0301 and the yield of GABA were explored by single factor test. The
results showed that glucose, nitrogen (tryptone and yeast extract) and L-MSG significantly influenced the growth of L. plantarum
MJ0301 and the yield of GABA (P ＜ 0.05). The response surface methodology was designed based on glucose, nitrogen (tryptone
and yeast extract) and L-MSG, and the yield of GABA was considered as response value. The optimal formulation of the culture
medium consisted of glucose 16.0 g/L, mixed nitrogen sources 10 g/L, L-MSG 30 g/L, ammonium citrate 2 g/L, K2HPO4
2 g/L, sodium acetate 5 g/L, magnesium sulfate 0.1 g/L, manganese sulfate 0.05 g/L, and Tween-80 1 mL/L. The resulting yield of
GABA was 1.59 g/L, which was 11.12-fold higher than before the optimization (143 mg/L).

Key words: Lactobacillus plantarum MJ0301；&gamma, -aminobutyric acid；response surface methodology