Optimisation of culture conditions for gamma-aminobutyric acid production in rice bran extracts

Abstract

Gamma-aminobutyric acid (GABA) is a potent bioactive component that widely exists in both plants and animals, has numerous health benefits. This study aimed to optimise the fermentation process conditions for the growth of Lactobacillus fermentum from rice bran extracts that have high potential to produce GABA. GABA content was assessed by thin-layer chromatography (TLC) method. In this study, fermenting conditions for medium production of GABA by L. fermentum from rice bran extracts were optimised. L. fermentum showed high potential for GABA-producing ability. Some factors influencing the GABA production such as carbon sources, nitrogen sources, mineral salt sources, substrate concentration of monosodium glutamate (MSG), pH, and the time of fermentation were investigated. When the L. fermentum is cultivated in the rice bran extracts medium supplemented with 1.5% lactose, 2% yeast extract, and 1% MSG with pH 6.0 in 48 h, this strain showed high GABA at a concentration of 736 mg/l.