关键词: 黑豆, 氨基酸, 相对分子质量, 内源蛋白酶, γ- 氨基丁酸

Abstract:

During sprouting process, a significant change in protease activity and gamma-aminobutyric acid (GABA) was observed in black soybean. In order to optimize the sprouting conditions of black soybean, GABA and endogenous proteases were investigated as indicators. Total protein amount, essential amino acid (EAA) and non-essential amino acid (NEAA) exhibited a significant increase, especially Asp, Met and GABA; in contrast, an obvious decrease of Lys was detected in the sprouting process of black soybean. In addition, an initial increase and a final decrease in the activity of endogenous proteases were also detected. Moreover, relative average molecular mass of proteins and GABA exhibited a significant decrease and increase, respectively. Therefore, the optimal conditions for sprouting of black soybean were soaking at 38 ℃ for 5 h followed by sprouting at 28 ℃ for 6 days. GABA and endogenous protease activity under these conditions were 94.4 mg/100g and 134.68 U/ml, respectively.

Key words: black soybean, amino acid, relative molecular mass, endogenous protease, GABA