桦褐孔菌多糖的分离纯化及其抗氧化活性测定

李欣欣; 李文香

doi:10.13386/j.issn1002-0306.2020040211

桦褐孔菌多糖的分离纯化及其抗氧化活性测定

Isolation, Purification and Antioxidant Activity of Inonotus obliquus Polysaccharide

摘要

摘要: 以桦褐孔菌为原料，测定其化学组分，并采用水提醇沉法提取桦褐孔菌粗多糖（IOP）。将获取的桦褐孔菌粗多糖进行脱蛋白、脱色素的初步纯化，然后利用DEAE-52纤维素层析柱及Sephadex-100凝胶柱对多糖提取液进行分离纯化，通过抗氧化活性筛选出活性较高的多糖组分，并通过高效液相色谱分析多糖组分的纯度。实验结果表明，桦褐孔菌子实体的化学成分组成丰富，其中多糖13.10%±0.31%、还原糖4.21%±0.40%、蛋白质2.70%±0.71%、灰分9.60%±0.31%。通过对桦褐孔菌粗多糖脱蛋白、脱色素的试验方法进行筛选，得到聚酰胺层析法为最佳的脱除方法。蛋白质的脱除率为93.1%、脱色率为75.8%，多糖的保留率为90.3%。IOP经过DEAE-52纤维素柱层析后得到四个单糖组分：IOP-1、IOP-2、IOP-3、IOP-4。对四个多糖组分进行抗氧化实验发现，IOP-2对DPPH自由基的清除率最高，清除率为81.9%。IOP-2经过Sephadex-100层析柱后获得两个多糖组分：IOP-2a、IOP-2b。对比其抗氧化活性，筛选出活性较高的多糖组分为IOP-2a。采用高效液相色谱法鉴定多糖组分IOP-2a，只检查出一个对称峰，说明IOP-2a为均一性多糖。

Abstract: The chemical compositions of Inonotus obliquus were analyzed and crude polysaccharides (IOP)were isolated from Inonotus obliquus by water extraction. The component of polysaccharides were purified by DEAE-52, and Sephadex G-100 column chromatography, and the highly active polysaccharide component was screened out through antioxidant activity, and the purity of the polysaccharide component was analyzed by high-performance liquid chromatography.The experimental results showed that the chemical composition of Inonotus obliquus was rich, including polysaccharide 13.10%± 0.31%, reducing sugar 4.21%±0.40%, protein 2.70%±0.71%, ash 9.60%±0.31%.After IOP undergoes DEAE-52 cellulose column chromatography, four monosaccharide components were obtained: IOP-1, IOP-2, IOP-3, and IOP-4. Antioxidation experiments on four polysaccharide components found that IOP-2 had the highest scavenging rate for DPPH free radicals. After passing through Sephadex-100 chromatography column, IOP-2 obtained two polysaccharide components: IOP-2a and IOP-2b. Compared with its antioxidant activity, the polysaccharide component with higher activity was selected as IOP-2a. Using high performance liquid chromatography to identify the polysaccharide component IOP-2a, only one symmetrical peak was detected, indicating that IOP-2a was a homogeneous polysaccharide.