Effect of different salt concentrations on the gamma-aminobutyric-acid content and glutamate decarboxylase activity in germinated sorghum ( Sorghum bicolor L. Moench) grain.

This study aimed to estimate the γ-aminobutyric acid (GABA) content and glutamate decarboxylase activity (GAD) in germinated sorghum grain as affected by different concentrations of NaCl, pyridoxal 5-phosphate (PLP), and CaCl 2 . In general, the obtained results revealed that the addition of low doses of NaCl (40 mmol/L), PLP (90 mmol/L), and CaCl 2 (0.5 mmol/L) to the germination culture significantly ( p  < .05) enhanced the GABA content and subsequently improved the GAD activity in sorghum grains. Moreover, CaCl 2 played a dominant role in the extent of enzymolysis, followed by NaCl and PLP. Regarding the GABA content, the optimal concentration of the NaCl, PLP, and CaCl 2 was estimated as 41.07 mmol/L, 82.62 μmol/L, and 0.40 mmol/L, respectively. Under this optimal culture medium, the maximum GABA content was 0.336 mg/g. In conclusion, the findings of this work would provide a scientific basis for the industrialized production of GABA-enriched sorghum foods.