淡紫擬青霉胞外多糖的分離、純化及結構分析

史懷，劉波，蘇明星，黃素芳，朱育菁

福建省農業科學院農業生物資源研究所，福州 350003

淡紫擬青霉胞外多糖的分離、純化及結構分析

史懷，劉波，蘇明星，黃素芳，朱育菁

福建省農業科學院農業生物資源研究所，福州 350003

淡紫擬青霉 NH-PL-03菌株的胞外多糖粗提物對枯萎病病原菌-尖孢鐮刀菌具有較好的抑制效果，文中對淡紫擬青霉胞外多糖進行了分離純化和結構分析，以期為其構效關系研究奠定基礎。采用乙醇沉淀法從淡紫擬青霉發酵液中提取粗多糖，經Sevage法脫蛋白后，過Superdex-G75凝膠層析柱分離得到胞外多糖EP-1。紫外分光法和Sephacryl S-200 HR凝膠層析柱檢測EP-1為均一多糖，Sephacryl S-200柱層析測得EP-1的分子量為35.2 kDa，完全酸水解后紙層析檢測EP-1的單糖組成中僅有葡萄糖，紅外光譜、高碘酸氧化和Smith降解結果表明EP-1的化學結構是以β-(1,3)糖苷鍵連接而成的無分枝的葡聚糖。剛果紅絡合試驗表明EP-1在稀的堿溶液中以3股螺旋構象存在。

淡紫擬青霉，多糖，結構分析

Abstract:The paper dealt with the characterization of polysaccharide ofPaecilomyces lilacinusNH-PL-03 strain.First, we extracted and purified exude polysaccharide from the fungal fermentation broth by ethanol depositing method.Second, the proteins were removed by the Sevage method from the crude polysaccharide.Third, the purified polysaccharide(EP-1)was obtained after Superdex G-75 column separation.The results of UV-spectrometer and Sephacryl S-200 HR chromatography experiments showed that the EP-1 was a homogeneous pure polysaccharide with molecular weight of 35.2 kDa.Tested by paper chromatography analysis using the complete hydrolysis by sulfuric acid, we found that the EP-1 comprise single component as glucose.The chemical structure of EP-1 was confirmed as a kind of linear glucan linked by β-(1,3)linkage.The Congo red reaction performed that EP-1 probable presented a triple-helica conformation in the dilute alkali.

Keywords:Paecilomyces lilacinus, polysaccharide, structure analysis

淡紫擬青霉Paecilomyces lilacinus(Thom)Samson屬半知菌綱、絲孢菌目、擬青霉屬，對多種植物寄生線蟲有著良好的防治效果[1-2]、此外還具有殺蟲[3]、促長[4]、拮抗[5]、降解[6]等多種功效，是極具推廣潛力的生防菌與功能菌。淡紫擬青霉生物學功能與其次生代謝物關系密切，該菌不但能分泌對線蟲具有毒殺作用的毒素[7-8]，還能分泌吲哚乙酸[9]、以及蛋白酶、淀粉酶、右旋糖苷酶等多種酶類[10-11]。國內對淡紫擬青霉在植物線蟲及病害生物防治上的應用進行了廣泛的研究，但對菌株所產生的各種次生代謝物的提取及結構、功能等深層次的研究十分薄弱。……