Abstract：
Walnut diaphragm is defined as a dry wood septum located between the walnut shell and kernel. In this work, seven phenolic compounds from walnut diaphragm were purified and characterized, and their antioxidant activities and mechanisms of hypoglycemia were investigated. Compounds 1-7 were tested for DPPH, ABTS scavenging ability, and FRAP assay to evaluate the antioxidant activity. α-Amylase inhibition assay was introduced to assess the hypoglycemic activity, and the mechanism was investigated by kinetic analysis, CD spectrum, and molecular docking. Compound 6 showed the strongest antioxidant ability, while compound 1 exhibited the strongest inhibition of α-amylase by changing the secondary structure of α-amylase in a mixed competitive inhibition mode. Molecular docking test predicted that the tetrahydropyran part in compound 1 may contribute to its hypoglycemic effect. This study furnishes a new theoretical reference for the utilization and development of walnut diaphragm into a health food with antioxidant and hypoglycemic properties. PRACTICAL APPLICATIONS: The finding of this research may serve as a basis for the subsequent development of walnut diaphragm into instant tea-based health food or added to other food carriers to achieve auxiliary antioxidant and hypoglycemic effects. This study revealed that polyphenolic components were the material basis for the antioxidant and hypoglycemic effects of walnut diaphragm, which could be identified as landmark chemical components for controlling quality standards in the development of walnut diaphragm, thus accelerating the research process of quality standards for walnut diaphragm-related products. Furthermore, the studies on the mechanism of hypoglycemic activity supply more credible data to support the development of walnut diaphragm into a safe and consumer-friendly health food. With abundant resources and clear efficacy, walnut diaphragm has great development prospect and application value.
摘要：
核桃隔膜被定义为位于核桃壳和内核之间的干木隔膜。在这项工作中,对核桃隔膜中的7种酚类化合物进行了纯化和表征，研究了它们的抗氧化活性和低血糖的机制。测试化合物1-7的DPPH，ABTS清除能力，和FRAP测定以评价抗氧化活性。引入α-淀粉酶抑制试验来评估降血糖活性，并通过动力学分析研究了机理，CD光谱,和分子对接。化合物6表现出最强的抗氧化能力，而化合物1通过以混合竞争抑制模式改变α-淀粉酶的二级结构表现出对α-淀粉酶的最强抑制作用。分子对接试验预测化合物1中的四氢吡喃部分可能有助于其降血糖作用。该研究为核桃隔膜在具有抗氧化和降血糖特性的保健食品中的利用和开发提供了新的理论参考。实际应用：本研究的发现可为后续将核桃隔膜开发成速溶茶型保健食品或添加到其他食品载体中以达到辅助抗氧化和降血糖作用奠定基础。这项研究表明，多酚成分是核桃隔膜抗氧化和降血糖作用的物质基础，可作为核桃隔膜开发过程中控制质量标准的标志性化学成分，从而加快了核桃隔膜相关产品质量标准的研究进程。此外，关于降血糖活性机制的研究为核桃隔膜发展成为安全、消费者友好的保健食品提供了更可靠的数据。资源丰富,疗效明确,核桃隔膜具有很大的发展前景和应用价值。
