Abstract

In order to study the extraction process and antioxidative activity of Inonotus obliquus polyphenols (IOP), the optimal extraction process was determined by orthogonal experiment optimization. The clearance rate of DPPH and hydroxyl radicals were used as indicators to evaluate the antioxidant activity of IOP. The results showed that the optimum extraction conditions were as follows: ethanol concentration of 50%, solid–liquid ratio of 1:20, temperature of 60 °C, and 90 min. Under these conditions, the extraction yield of IOP was 2.84%. The antioxidant capacity of extracts appeared to be IOP dose-dependent, while it also presented stronger ferric reducing antioxidant power (FRAP). High Performance Liquid Chromatography (HPLC-MS) analysis indicated that the major identified polyphenol compounds extracted at the optimal conditions were ten compounds (procyanidin, caffeic acid, p-coumaric acid, isorhamnetin-3-O-glucoside, astilbin, tangeretin, gallic acid, kaempferol, quercetin, and catechin 7-xyloside). These findings indicate that I. obliquus polyphenols have the potential to be developed as a natural antioxidant and have a good application prospect.

摘要

为了研究斜切inonotus的提取工艺和抗氧化活性多酚（IOP），通过正交实验优化确定最佳提取工艺。以DPPH和羟基自由基的清除率作为评价IOP抗氧化活性的指标。结果表明，最佳提取条件为：乙醇浓度为50％，固液比为1:20，温度为60°C和90分钟。在这些条件下，IOP的提取率为2.84％。提取物的抗氧化能力似乎是IOP剂量依赖性的，同时还表现出较强的三价铁还原抗氧化能力（FRAP）。高效液相色谱（HPLC-MS）分析表明，在最佳条件下提取的主要鉴定出的多酚化合物为十种化合物（原花青素，咖啡酸，对香豆酸，异鼠李素-3-O-葡萄糖苷，甜菜碱，桔皮，没食子酸，山奈酚，槲皮素和儿茶素7-木糖苷）。这些发现表明I.斜多酚具有被开发为天然抗氧化剂的潜力并且具有良好的应用前景。