[关键词]
[摘要]
采用酶动力学方法研究了生姜汁对α-葡萄糖苷酶活性的抑制作用并对其抑酶物质进行了光谱分析。结果表明:山东大姜姜汁对α-葡萄糖苷酶活性的抑制效果最好(抑制率最高可达73.38%),酶动力学实验及Lineweaver-Burk双倒数作图结果显示姜汁对α-葡萄糖苷酶活性的抑制作用表现为可逆竞争性抑制;5 ℃贮藏后姜汁对酶活性的抑制率降低至初期的46.50%,贮藏后的姜汁在热处理过程中对酶活性的抑制率表现为先升高后降低的趋势;超滤分离组分抑酶效果表明,姜汁MW≥10 ku组分相比于其他组分对酶活性的抑制率最高,可达67.16%,说明姜汁中发挥抑制酶活性作用的物质主要集中在MW≥10 ku的组分中;在姜汁与α-葡萄糖苷酶的混合体系中,姜汁成分在紫外吸收光谱240~280 nm波段处,吸光值显著降低,说明姜汁中发挥抑酶活性的部分成分分布在240~280 nm波段处。该研究为深入开展姜汁降血糖活性研究及其深加工产品的开发奠定了理论基础。
[Key word]
[Abstract]
Enzyme kinetics and spectroscopic analyses were performed to determine the inhibitory effects of ginger juice on α-glucosidase activity and possible inhibitory substances involved were explored. The results showed that the inhibitory effect of Shandong ginger juice on α-glucosidase activity was the best, with an inhibition rate of 73.38%. The results of enzyme kinetics and Lineweaver-Burk double reciprocal analysis showed that the inhibitory effects of ginger juice on α-glucosidase activity were reversible and competitive. The inhibition rate of ginger juice on enzyme activity decreased to 46.5% of the initial inhibition rate after 3 days of storage at 5 ℃. Enzyme activity inhibition rates of stored ginger juice during heat treatment first increased before decreasing. Analysis of components separated by ultrafiltration showed that inhibition rate (67.16%) of the MW≥10 ku component in ginger juice was the highest among components. This indicates that the substances with enzyme inhibiting activity were mainly concentrated in the MW≥10 ku component of ginger juice. In the mixed system of ginger juice and α-glucosidase, the absorbance value of ginger juice components decreased significantly in the ultraviolet absorption spectrum of 240~280 nm, indicating that the components with inhibitory activity in ginger juice were distributed in this band. The results of this study provide a theoretical basis for further research on the hypoglycemic activity of ginger juice as well as the development of further processed products.
[中图分类号]
[基金项目]
国家自然科学基金项目(31972464)