松木层孔菌杂多糖中的3-O-甲基-半乳糖的分析鉴定

Identification of 3-O-methyl-galactose in heteropolysaccharide isolated from the fruiting body of Phellinus pini

目的:分析鉴定松木层孔菌子实体杂多糖中的未知单糖组分。方法:松木层孔菌子实体经提取分离纯化得到水溶性均一多糖组分PP80W,HPLC法测定其均一性和分子量。PP80W经水解、还原和乙酰化后采用GC法对照测定其单糖组分,并对其中未知的1个单糖组分采用GC-MS、DEPT-135和2D NMR(1H-1H COSY、TOCSY、HMQC、HMBC和NOESY谱)进一步分析鉴定。结果:PP80W相对分子质量为2.99×103,GC分析发现PP80W由鼠李糖、甘露糖、葡萄糖、半乳糖和1种未知单糖构成,GC-MS和核磁共振分析鉴定该未知单糖为3-O-甲基-半乳糖。结论:PP80W为含有3-O-甲基-半乳糖结构的杂多糖组分。

Objective： To identify an unknown sugar component in polysaccharide PP80 W purified from the fruiting body of Phellinus pini. Methods： A water-soluble and mono-disperse polysaccharide PP80 W was obtained from the fruiting body of Phellinus pini by hot water extraction,separation and purification. The homogeneity and molecular weight of PP80 W were analyzed by HPLC. PP80 W was hydrolyzed with TFA,reduced with Na BH4 and acetylated with acetic anhydride. Then the monosaccharide composition of PP80 W was analyzed by GC. GC-MS,DEPT-135 and 2D NMR（^1H-^1H COSY,TOCSY,HMQC,HMBC and NOESY spectra） were further used to identify the unknown sugar component. Results： PP80 W,with a relative molecular mass of 2. 99 × 10^3,was determined to be composed of rhamnose,mannose,glucose,galactose and an unknown monosaccharide by GC analysis. The unknown monosaccharide was identified as 3-O-methyl-galactose by GC-MS and NMR analysis. Conclusion： PP80 W was a heteropolysaccharide contain 3-O-methyl-galactose.