Abstract: Based on the single factor tests, the effects of NaCl content, culture time and culture temperature on γ-aminobutyric acid (GABA) accumulation during the germination of soybean (Glycine max L.) were explored by response surface methodology (RSM). The objective of this study was to optimize the culture conditions for GABA production in germinated soybeans under salt stress. The results showed that the optimal conditions with salt stress for GABA accumulation in germinated soybean were NaCl content of 133.5 mmol/L, culture time of 5.5 days and culture temperature of 33.3 ℃. Under the optimal conditions, the predicted highest GABA yield was up to 1205.24 μg/g. Analysis of variance and validation experiments for the regression model suggested that the model could accurately predict GABA accumulation in germinated soybean under salt stress.

Key words: soybean, germination, salt stress, γ-aminobutyric acid accumulation, response surface methodology