白腐真菌Hypocrea lixii SCSIO 41520次级代谢产物及抗菌活性研究

对来源于深圳大亚湾近海水域软珊瑚中分离得到的白腐真菌Hypocrea lixii SCSIO 41520的次级代谢产物及抗菌活性进行研究。采用硅胶柱层析、凝胶Sephadex LH-20柱层析、半制备HPLC等色谱技术对其进行分离纯化,通过1H NMR、13C NMR、MS等波谱技术鉴定化合物结构。共分离鉴定了8个化合物,分别为4-(5,7-dimethoxy-4-oxo-4H-chromen-2-yl)heptanoic acid methyl ester(1)、5-methoxy eugenin(2)、rugulosin(3)、大黄素(4)、3-(5,7-dimethoxy-4-oxo-4H-chromen-2-yl)propanoic acid(5)、comazaphilone C(6)、kasanosin C(7)、comazaphilone E(8),其中化合物1是新化合物。纸片扩散法抗菌实验结果显示,该真菌发酵产物的乙酸乙酯粗提物及各分离组分均有一定的抗菌活性,单体化合物中,化合物3在25μg/disc的浓度下对金黄色葡萄球菌、枯草芽孢杆菌、大肠杆菌有显著抑制作用,抑菌圈直径分别为16、15、9 mm。

盐酸普鲁卡因诱导下海洋真菌Hypocrea lixii次级代谢化学成分

【目的】通过化学诱导方法从一株海洋真菌Hypocrea lixii中获得多样化的活性小分子化合物。【方法】对菌株在盐酸普鲁卡因的化学诱导作用下进行固体发酵,代谢产物采用硅胶减压柱层析、Sephadex LH-20以及pHPLC等手段分离纯化,对化合物运用NMR、MS等波谱学技术并比对文献进行结构鉴定,采用Ellman比色法及DPPH自由基清除法对化合物进行初步抗乙酰胆碱酯酶(AChE)和抗氧化活性测试。【结果】从海洋真菌Hypocrea lixii在盐酸普鲁卡因诱导下的发酵提取物中分离得到4个异黄酮类化合物,包括6''-O-crotonylgenistin(1)、Genistein(2)、Daidzein(3)和Genistin(4),以及对氨基苯甲酸甲酯(5)、对羟基苯丙酸(6)和胞嘧啶(7),其中化合物1和6为该种中首次报道,化合物5为生物转化来源首次报道,化合物2~4可能源自培养基。在100μmol/L剂量浓度下,化合物1~4对AChE的抑制以及DPPH自由基的清除活性均较弱,化合物5和6显示了相对强的AChE抑制活性,抑制率分别为40%和38%。【结论】盐酸普鲁卡因对该菌次级代谢产生了显著的影响,为深入研究该菌株化学诱导次级代谢产物提供基础。

红树林真菌Hypocrea lixii VB1的抗癌及抗菌活性(英文)

AIM:Mangrove is one of the oldest living tree species and its leaves are among the most extensively studied botanicals in use today.Scientific research throughout the world has found evidence to support the fact that its foliar extracts have great potential against human microbial pathogens.This study highlights the isolation of foliar fungi from Rhizophora mucronata,Avicenna officialis and Avicenna marina.METHOD:It was isolated in Sabouroud's Dextrose Agar and mass cultivation was done in Sabouroud's Dex-trose broth.RESULTS:The ethyl acetate extract showed maximum antibacterial activity which inturn checked for different concentra-tion against bacterial pathogens and anticancer activity for Hep2 and MCF7 cell line in vitro.The DNA was isolated from the fungi and the ITS region of 5.8 s RNA was sequenced and assigned to new species as they are separated from the type strains phylogenetic neighbors by sequence similarities.CONCLUSION:This preliminary screening of fungal endophytes revealed their potential to yield potent bioactive compounds for drug discovery programmes.