四种食用菌糖蛋白粗提物体外抗氧化和抑菌活性比较

Comparison of Antioxidant and Antibacterial Activities of Crude Glycoprotein Extracts from Four Edible Fungi In vitro

采用超声波辅助水提醇沉法获得美味红菇(Russula delica)、美味牛肝菌(Boletus edulis)、荷叶离褶伞(Lyophyllum decastes)和翘鳞肉齿菌(Sarcodon imbricatus)糖蛋白粗提物,采用十二烷基硫酸钠-聚丙烯酰胺凝胶电泳测定其多糖和蛋白质相对分子质量;采用傅立叶变换红外吸收光谱仪测定其化学组成;采用苯酚硫酸法测定其多糖含量、考马斯亮蓝法测定蛋白质含量;分别测定粗提物对DPPH自由基、ABTS自由基清除能力、总还原力以及对大肠杆菌、金黄色葡萄球菌的抑菌活性。结果表明:4种食用菌粗提物中均存在糖蛋白,相对分子质量为(2.5~6)×10~4;糖蛋白粗提物中具备典型蛋白和多糖红外吸收特征;在实验范围内,2.5mg·mL^(-1)翘鳞肉齿菌糖蛋白粗提物对ABTS自由基、DPPH自由基的清除率最大,分别为(89.09±4.31)%和(54.95±0.56)%,3 mg·mL^(-1)翘鳞肉齿菌糖蛋白粗提物总还原力0.99±0.051最强;美味牛肝菌、翘鳞肉齿菌分别对大肠杆菌和金黄色葡萄球菌抑菌活性强。

Using ultrasound-assisted aqueous hydrotropic alcohol precipitation,crude glycoprotein extracts of Russula delica,Boletus edulis,Lyophyllum decastes and Sarcodon imbricatus were obtained respectively.These crude glycoprotein extracts were then determined for molecular weight by SDS-PAGE,chemical composition by Fourier transform infrared absorption spectrometer(FTIR),polysaccharide content by the phenol sulfate method,and protein content by Coomassie blue staining.Their antioxidant activity was assessed in terms of DPPH radical scavenging ability,ABTS radical scavenging ability,and total reducing capacity.These crude glycoprotein extracts were also determined for antibacterial activity against Escherichia coli and Staphylococcus aureus.The results showed that glycoproteins were found in the crude extracts of all four edible fungi,and their molecular weights ranged from 2.5×10~4 to 6×10~4.There were typical infrared absorption characteristics of protein and polysaccharide in the crude glycoprotein extracts.Within the experimental range,2.5 mg·mL~(-1) S.imbricatus crude glucoprotein extract had the highest scavenging rate against ABTS and DPPH free radicals,which were(89.09±4.31)% and(54.95±0.56)%,respectively.The crude glycoprotein extract of S.imbricatus also had the highest total reducing power of 0.99±0.051 at 3 mg·mL~(-1).For antibacterial activity,the crude glycoprotein extracts from B.edulis and S.imbricatus showed strong activity against E.coli and S.aureus,respectively.