为探究果汁在复配体系中对于生物活性的协同增效作用，选择具有丰富天然活性物质的桑葚、百香果、柚子、火龙果为原材料，以多酚含量等比例混合制备得到复合果汁，评价其抗氧化及降血糖活性。结果表明，通过果汁复配，果汁样品的氧化自由基吸收能力无明显改善，而降血糖活性研究结果显示，复合果汁抑制α-葡萄糖苷酶的IC50值在0.16~0.25 mg GAE/mL之间，均小于单一果汁的IC50值（0.30~0.49 mg GAE/mL），表明复配对α-葡萄糖苷酶的抑制作用表现出显著的增强效果，且联合指数均小于0.9，其中柚子与桑葚-百香果-火龙果的联合指数最低为0.57。抑制动力学研究表明，桑葚果汁表现为对α-葡萄糖苷酶的非竞争型抑制，而其他三种果汁均为混合型抑制，抑制常数以桑葚果汁最低为22.2 mg/mL。总的来说，桑葚、百香果、柚子、火龙果果汁复配具有一定的增强对α-葡萄糖苷酶的抑制作用的效果，各组分表现出协同作用，且机制研究表明，具有较强活性的桑葚果汁可作为一种非竞争性抑制的原料应用于复合果汁中。

In order to study the synergistic effect of juice on bioactivity in compound system, mulberry fruit, passion fruit, pomelo and pitaya fruit with rich active substances were selected as materials. The four single juices were mixed based on polyphenol contents, and their antioxidant and hypoglycemic activities were examined. The results showed that the oxygen radical absorbance capacity of compound juice showed no significant improvement. The inhibitory activities on α-glucosidase were significantly enhanced, specifically, the IC50 values of compound juice were between 0.16~0.25 mg GAE/mL, both less than those of single juice (0.30~0.49 mg GAE/mL). The combination index values were all less than 0.9, among which the value of pomelo and mulberry fruit-passion fruit-pitaya fruit showed the lowest value of 0.57. The inhibition kinetics research indicated that mulberry fruit juice exhibited non-competitive inhibition type on α-glucosidase, while the other three juices were mixed inhibition type. Moreover, the lowest inhibition constant was 22.2 mg/mL in mulberry fruit juice. Generally, this research demonstrated that the combination of fruit juice had synergistic effect on enhancing α-glucosidase inhibition activity. Furthermore, the mulberry fruit juice with great activity was suggested to be used as the non- competitive inhibition material in compound juice.

国家重点研发计划项目（2017YFD0400703-2）；国家自然科学基金资助项目（32001647）