发芽蚕豆富集γ-氨基丁酸的培养液组分优化

摘要

以蚕豆为试材,研究谷氨酸钠(MSG)、CaCl2、和VB6对发芽蚕豆谷氨酸脱羧酶(GAD)及γ-氨基丁酸(GABA)的影响,采用Box - behnken设计对发芽蚕豆富集GABA的培养液组分进行了优化,并对发芽蚕豆富集GABA的二次回归模型进行分析.结果表明,低氧联合盐胁迫下,MSG、CaCl2和VB6对发芽蚕豆GAD及GABA的影响均达到显著水平(P ＜0.005).经过回归分析建立了GABA含量对培养液组分的二次回归模型,回归方程的决定系数达到0.976,说明方程能很好的预测GABA富集含量的变化.蚕豆富集GABA的最适培养液组分为MSG 1.1 mg/mL、CaCl2 6.1 mmol/L、VB672 μmol/L,此时,GABA富集量达到(1.98 ±0.09)mg/g DW,为对照[(1.08±0.01 )mg/g DW]的1.83倍.%In this paper, the effects of MSG, CaCl2 and VB6 on glutamate decarboxylase ( GAD) and 7 - ami-nobutyric acid (GABA) of germinated fava beans were investigated. The culture solution compositions used for GA-BA accumulation in fava beans were optimized with Box - Behnken design. The results showed that under the condition of hypoxia combined with salt stress, the effects of MSG, CaCl2 and VB6 on GAD and GABA of germinated fava beans all reached significant levels ( P < 0. 005 ). The quadric regression equation was established between GABA content and culture solution compositions. The R - squared reached 0. 976, which meant that the equation could predict the changes of accumulation contents of GABA well. The optimum compositions of culture solution for GABA accumulation were MSG of 1. 1 mg/mL, CaCl2 of 6. 1 mmol/L and VB6 of 72 pjnol/L. Under these conditions, the content of GABA was (1.98 ±0.09) mg/g DW, which was 1. 83 times as much as that of the control [ (1. 08 ± 0.01) mg/gDW].