黑芝胞外多糖提取工艺条件优化及体外抗氧化活性研究

Optimization of Extraction Technology of Extracellular Polysaccharide from Fermentation Broth Ganoderma atrum and Study on Its Antioxidant Activity in vitro

本研究采用改进的苯酚-硫酸法测定黑芝多糖含量,以多糖提取率为评价指标,在单因素试验的基础上,进行正交试验,考察乙醇浓度、提取时间、发酵液pH值三个因素对多糖得率的影响。结果表明,最佳提取工艺条件为乙醇浓度80%、提取时间19h、发酵液pH5.5。在此条件下黑芝胞外多糖得率为5.2343g/L。黑芝多糖浓度为40mg/ml时,对·OH与DPPH自由基的清除率分别达到39.85%和23.4%,表明黑芝多糖具有明显的抗氧化活性。

The content of polysaccharide of Ganoderma atrum was determined by the method of improved phenol-sulphate acid. On the basis of single-factor tests, orthogonal design was applied to analyze the effects of ethanol concentration, extraction time and broth pH value on the extraction rate of polysaccharides. The results showed that the optimum ethanol concentration, extraction time and broth pH value are 80%, 19 h, and 5.5, respectively. Under these conditions, the extraction yield of extracellular polysaccharide is 5.2343 g/L. At the concentration of 40 mg/ml, the hydroxyl and DPPH radicals-scavenging activities of the polysaccharide are 39.85 % and 23.4 %, respectively. It indicated that the extracellular polysaccharide produced by Ganoderma atrum has a significant antioxidant activity.