一株黄芪内生真菌甾醇类代谢产物的分离和鉴定

目的:研究分离自夏季黄芪根部的内生真菌AR-17-S03的次级代谢产物。方法:采用组织学的方法从恒山黄芪中分离内生真菌,真菌的鉴定采用形态学法结合分子生物学法,采用硅胶柱色谱法、薄层层析制备色谱(pTLC)、Sephadex LH-20凝胶柱色谱法和半制备HPLC色谱法分离内生真菌代谢产物,采用质谱法、核磁共振法结合物化性质鉴定分离得到的9个化合物。结果:经形态学结合分子生物学鉴定该菌株黑曲霉,为9个甾醇类化合物鉴定为麦角甾醇、过氧化麦角甾醇、胆固醇、啤酒甾醇、23-甲基麦角甾-7,22-二烯-3β,5α,9α-三醇、5α,8α-表二氧麦角甾-6,9(11),22-三烯-3β-醇、5α,8α-表二氧-23-甲基麦角甾-6,22-二烯-3β-醇、麦角甾-4,6,8(14),22-四烯-3-酮、3β,5α-二羟基麦角甾-7,22-二烯-6-酮。结论:其中,23-甲基麦角甾-7,22-二烯-3β,5α,9α-三醇、5α,8α-表二氧-23-甲基麦角甾-6,22-二烯-3β-醇、麦角甾-4,6,8(14),22-四烯-3-酮是首次从黄芪内生真菌中分离得到。

Separation and Identification of Sterols from Endophytic Fungus of Astragalus membranaceus

Objective:Study on secondary metabolites from endophytic fungus AR-17-S03 isolated from the roots of Astragalus membranaceus in summer. Methods:Endophyic fungus was isolated from Astragalus membranaceus by the method of histology. The fungus was identified by morphological method combined with molecular biology method. The compounds were isolated by column chromatography,pTLC,Sephadex LH-20 and pre-HPLC. And they were identified by the spectral analysis of mass spectrometry and nuclear magnetic resonance. Results:Endophytic fungi AR-17-S03 isolated from roots of Astragalus membranaceus were identified as Aspergillus niger. Nine sterols were obtained and identified as ergosterol,ergosterol peroxide,cholesterol,cerevistero,23-methylergosta-7,22-diene-3β,5α,9α-triol,5α,8α-epidioxy-ergosta-6,9(11),22-trien-3β-ol,5α,8α-epidioxy-23-methylergosta-6,22-diene-3β-ol,ergosta-4,6,8(14),22-tetraen-3-one and 3β,5α-dihydroxy-ergosta-7,22-diene-6-one. Conclusion:23-methylergosta-7,22-diene-3β,5α,9α-triol,5α,8α-epidioxy-23-methylergosta-6,22-diene-3β-ol and ergosta-4,6,8(14),22-tetraen-3-one were obtained from the endophytic fungus of Astragalus membranaceus for the first time.