基于糖谱法的僵蚕多糖结构特征分析及抗氧化活性研究

Structural characteristics and antioxidant activities of polysaccharides from Bombyx batryticatus basedupon saccharide mapping

目的:通过糖谱法分析僵蚕(Bombyx batryticatus)及麸炒僵蚕多糖的整体结构特征,并对僵蚕、麸炒僵蚕多糖及其水解物的体外抗氧化活性进行分析。方法:对僵蚕及麸炒僵蚕多糖进行酸水解和不同糖苷酶酶解后,采用高效薄层色谱法(high performance thin layer chromatography,HPTLC)和荧光辅助凝胶电泳法(polysaccharide analysis of carbohydrate gel electrophoresis,PACE)分析水解产物的结构特征。采用2,2′-联氮-双(3-乙基苯并噻唑啉-6-磺酸)自由基与1,1-二苯基-2-三硝基苯肼自由基清除实验测定僵蚕、麸炒僵蚕多糖及其水解物的体外抗氧化活性。结果:通过HPTLC和PACE法分析结果发现,僵蚕及麸炒僵蚕多糖均能被β-半乳糖酶、纤维素酶、葡聚糖酶和果胶酶水解,几乎不能被β-甘露糖酶水解;体外抗氧化实验结果表明,僵蚕、麸炒僵蚕多糖经酸水解和纤维素酶水解后抗氧化活性降低,而经β-半乳糖酶、葡聚糖酶、果胶酶水解后抗氧化活性增强;与僵蚕相比,麸炒僵蚕多糖及其水解物的抗氧化活性均降低。结论:僵蚕及麸炒僵蚕多糖均含有β-吡喃半乳糖苷键、β-1,4-葡萄糖苷键、α-1,6-葡萄糖苷键和α-1,4-半乳糖醛酸苷键。此外,僵蚕、麸炒僵蚕多糖及其水解物均具有良好的抗氧化能力,该研究可为僵蚕多糖的进一步开发利用和中药多糖结构特征分析提供参考依据。

OBJECTIVE To explore the overall structural characteristics of Bombyx batryticatus polysaccharides through saccharide mapping and antioxidant activities of polysaccharide and analyze in vitro its hydrolysate from Bombyx batryticatus poly⁃saccharide and fried Bombyx batryticatus.METHODS After acid hydrolysis and enzymolysis with different glycosidases of poly⁃saccharides from Bombyx batryticatus and fried Bombyx batryticatus,structural characteristics of hydrolysates were examined by high performance thin layer chromatography(HPTLC)and polysaccharide analysis of carbohydrate gel electrophoresis(PACE).The in vitro antioxidant activity of polysaccharides and their hydrolysates from Bombyx batryticatus and fried B.batryticatus was measured by ABTS/DPPH radical scavenging.RESULTS Results of HPTLC/PACE indicated that the polysaccharide of Bom⁃byx batryticatus and fried Bombyx batryticatus could be hydrolyzed byβ-galactozyme,glucanase,cellulase and pectinase,but not byβ-mannozyme.Antioxidant in vitro assays demonstrated that the antioxidant capacities of polysaccharides and their hydroly⁃sates from Bombyx batryticatus and fried Bombyx batryticatus declined after acid/cellulase hydrolysis while antioxidant activities became enhanced after hydrolysis of galactose,glucanase and pectinase.The antioxidant activities of polysaccharide and its hydro⁃lysate weakened as compared with that of Bombyx batryticatus.CONCLUSION The polysaccharides of Bombyx batryticatus and fried Bombyx batryticatus containβ-galactopyranoside,β-1,4-glucoside,α-1,6-glucoside andα-1,4-galacturonic acid glyco⁃sidic bonds.In addition,polysaccharides and their hydrolysates from Bombyx batryticatus and fried Bombyx batryticatus had excellent antioxidant capacities.It provided references for further utilizations of polysaccharides from Bombyx batryticatus and advanced elucidations of polysaccharide structural characteristics of traditional Chinese medicine.