不同粉碎程度下杜仲叶理化性质及体外降血糖、抗氧化活性的变化

Changes in the Physicochemical Properties and in Vitro Hypoglycemic and Antioxidant Activities of Eucommia Ulmoides Leaves under Different Crushing Degrees

摘要:

杜仲叶具有与杜仲皮相似的化学成分及生物活性，是其潜在的中药替代品。为探究粉碎对杜仲叶理化性质、活性成分及其体外活性的影响，该研究采用粗粉碎和超微粉碎技术制备了三种不同粒径的原料：粗粉末、100目粉末和超微粉末，考察了杜仲叶理化性质、多糖含量、体外降糖活性和抗氧化活性。结果表明，杜仲叶超微粉末粒径为D50 = 9.63 μm，堆积密度、振实密度、持水力、持油力及溶解度均高于其他两种样品，但流动性较差，多糖质量分数为22.47%，其多糖对α-葡萄糖苷酶、α-淀粉酶的抑制率及对DPPH·、O- 2·、·OH的清除率均显著优于其他样品。综上，相较于粗粉碎和100目粉碎，超微粉碎有效改善了杜仲叶粉末的理化特性，增强体外降糖和抗氧化活性，可作为杜仲叶在食品和药品领域大规模生产的有益预处理加工方式。此外，杜仲叶超微粉末也是功能食品和营养保健品的可用原料。

Abstract:

Eucommia ulmoides leaves are a potential alternative to Eucommia ulmoides bark in traditional Chinese medicine because of their similar chemical constituents and biological effects. To investigate the impact of grinding on the physicochemical properties, active ingredients, and its in vitro activities of Eucommia ulmoides leaves,three raw materials with different particle sizes (ultrafine powder, 100-mesh powder, and coarse powder) were prepared using superfine grinding and coarse grinding techniques. The physicochemical properties, polysaccharide content, in vitro hypoglycemic activity, and antioxidant activity of Eucommia ulmoides leaves were examined. The results showed that the superfine powder of Eucommia ulmoides leaves had the smallest particle size (D50 = 9.63 μm), with the highest bulk density, tapped density, water-holding capacity, oil-holding capacity, and solubility; however, its fluidity was poor. The contents of polysaccharides (22.47%) in the superfine powder were the highest, and the inhibition rates of its polysaccharides on α-glucosidase and α-amylase, as well as the scavenging rates on DPPH·, O- 2·, and ·OH, were significantly superior to those of other samples. In conclusion, superfine grinding effectively improved the physicochemical properties of Eucommia ulmoides leaf powder and enhanced its in vitro hypoglycemic and antioxidant activities, which could be used as a beneficial pretreatment method for large-scale production of Eucommia ulmoides leaves in the food and pharmaceutical fields. Additionally, the superfine powder of Eucommia ulmoides leaves is also a usable raw material for functional foods and nutritional applications.