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.