桦褐孔菌多糖的硫酸化修饰及生物活性研究

Studies on Sulfated Modification and Biological Activity of Polysaccharides of Inonotus Obliquus

研究探讨桦褐孔菌胞内、胞外多糖经过硫酸化修饰后其化学组成与生物活性的变化.利用水溶醇沉法 提取了胞外多糖 EPS 和胞内多糖 IPS.以 EPS 为样品,通过正交实验确定了最佳的硫酸化修饰条件为反应温度 75℃ ,反应时间2. 5h ,反应摩尔比1 ： 2.5.在同样修饰条件下,胞外多糖取代度要高于胞内多糖取代度.桦褐孔菌 胞内、胞外多糖经硫酸化修饰后,糖含量、蛋白质含量以及糖醛酸含量都有所降低,然而硫酸化修饰多糖展示出了更 强的 DPPH 清除活性以及更低的IC50值.这表明桦褐孔菌胞外、胞内多糖经硫酸化修饰后,有效提高了抗氧化活 性,利于其进一步开发利用.

This research aims to discuss chemical composition and biological activity of intracellular and extracellular polysaccharides of Inonotus obliquus after sulfated modification.extracellular polysaccharide(EPS)and intracellular polysaccharide(IPS)were extracted by water ethanol method.By using the EPS as the sample,the orthogonal experiments were applied to confirm the optimum modification conditions as follows:reaction temperature 75℃,reaction time 2.5h,molar ratio 1∶2.5.Under the same modification conditions,the substitution degree of EPS was higher than that of IPS.The contents of sugar,uronic acid and protein of polysaccharides decreased after sulfated modification,while the polysaccharide modified by sulfation exhibited significantly stronger DPPH elimination activity and lower IC50 value.These show that sulfated modification can enhance the antioxidant activity of polysaccharides of Inonotus obliquus,and contribute to further development and utilization of polysaccharides.