一株蒲公英内生真菌Epicoccum sorghinum 1-2次级代谢产物研究

Secondary metabolites from the dandelion-derived endophytic fungus Epicoccum sorghinum 1-2

运用硅胶柱、凝胶柱和半制备高效液相色谱等方法对一株蒲公英内生真菌Epicoccum sorghinum 1-2发酵产物中的次级代谢产物进行分离纯化,通过核磁共振谱(NMR)及质谱(MS)等现代波谱分析方法进行化合物的结构解析,并采用滤纸片法测定化合物的抗菌活性。最终从E.sorghinum 1-2的发酵产物中分离鉴定了7个化合物,分别为(4R*,5R*,6S*)-4,5-二羟基-6-(6'-甲基水杨酸氧基)-2-甲氧基甲基-2-环己烯-1-酮(1)、(4R*,5R*,6S*)-4,5-二羟基6-(6′-甲基水杨酸氧基)-2-甲基-2-环己烯-1-酮(2)、(4R,5R,6S)-4,5-二羟基-6-(6′-甲基水杨酸氧基)-2-羟基甲基-2-环己烯-1-酮(3)、(-)-gabosine E(4)、theobroxide(5)、3-氯代龙胆醇(6)和3-羟基苯甲醇(7)。其中化合物1~5是顶环氧菌素类化合物,化合物6和7是苯酚类化合物。化合物1和2为首次报道的新化合物,化合物6对金葡菌具有显著的抑菌作用。

The secondary metabolites from the dandelion-derived Epicoccum sorghinum 1-2 were isolated by silica gel and Sephadex gel column chromatography,and semi-preparative high performance liquid chromatography(HPLC).Their structures were identified by comprehensive NMR and MS methods.Their antibacterial activities were determined by filter paper method.Finally,seven compounds were isolated and identified from the fermenta‐tion product of E.sorghinum 1-2,including(4R*,5R*,6S*)-4,5-dihydroxy-6-(6'-methylsalicyloxy)-2-methoxymethyl2-cyclohexen-l-one(1),(4R*,5R*,6S*)-4,5-dihydroxy-6-(6′-methylsalicyloxy)-2-methyl-2-cyclohexen-1-one(2),(4R,5R,6S)-4,5-dihydroxy-6-(6'-methylsalicyloxy)-2-hydroxymethyl-2-cyclohexen-1-one(3),(-)-gabosine E(4),theobroxide(5),3-chlorogentisyl alcohol(6),and 3-hydroxybenzyl alcohol(7),of which 1-5 are epoxydons,and 6 and 7 are phenolics.Compounds 1 and 2 are new structures reported for the first time.Compound 6 showed significant antibacterial activity against Staphylococcus aureus.