Enrichment of GABA in wastewater of tofu by lactic acid bacteria
The optimization of the culture medium in wastewater of tofu and the best fermentation conditions which produced GABA by Lactobacillus bulgaricus 1.0205 strain in optimal medium were studied.Then the fermentation process was analyzed.It was shown that the composition of optimal medium was as follows:glucose 2%,peptone 2%,(NH4)SO4 1%,KH2SO4 0.08%.GABA yield could reach 6.22 g/L under the conditions of inoculation amount 3%,reaction temperature 42 ℃,initial pH7,sodium glutamate 2%,fermentation time 40 h.This method can not only get high concentrations of γ-aminobutyric acid,but also make the wastewater of tofu be further utilized,and may provide new research directions and methods for the industrial production of γ-aminobutyric acid.