polyketide and benzopyran compounds of an endophytic fungus isolated from Cinnamomum mollissimum:biological activity and structure

Objective:To study bioactivity and compounds produced by an endophytic Phoma sp.fungus isolated from the medicinal plant Cinnamomum mollissimum.Methods:Compounds produced by the fungus were extracted from fungal broth culture with ethyl acetate.This was followed by hioaclivity profiling of the crude extract fractions obtained via high performance liquid chromatography.The fractions were tested for cytotoxicity to P388 murine leukemic cells and antimicrobial activity against bacteria and pathogenic fungi.Compounds purified from active fractions which showed antibacterial,antifungal and cytotoxic activities were identified using capillary nuclear magnetic resonance analysis,mass spectrometry and admission to AntiMarin database.Results:Three known compounds,namely 4—hydroxymellein,4,8—dihydroxy—6—melhoxy—3—methyl—3,4-dihydro—1H-isochromen-1—one and 1—(2,6-dihydroxyphenyl) ethanone,were isolated from the fungus.The polyketide compound 4—hydroxymellein showed high inhibitory activity against P388 murine leukemic cells(94.6%) and the bacteria Bacillus sublilis(97.3%).Meanwhile.4,8—dihydroxy-6—melhoxy—3—meth) 1—3,4-dihydro—1H—isochromen—1-one,a benzopyran compound,demonstrated moderate inhibitory activity against P388 murine leukemic cells(48.8%)and the fungus Aspergillus niger(56.1%).The second polyketide compound.1(2,6—dihydroxyphenyl)ethanone was inactive against the tested targets.Conclusions:These findings demonstrate the potential of endophytes as producers ol pharmacologically important compounds,including polyketides which are major secondary metabolites in fungi.

Dysoxylumasins A--F＂ Six New Limonoids from Dysoxylum mollissimum BI.

Six new mexicanolide-type limonoids, dysoxylumasins A-F （1-6）, together with eight known compounds, namely litseagermacrane, 15-methoxyisodauc-3-ene-1β, 5α-diol, isodauc-6-ene-10β,14-diol, 4-epi-isodauc-6-ene- 10β,14-diol, 2a,3a,4β-trihydroxypregnan-16-one, 1,7-phenanthrenedimethanol, spicatin, and aurantiamide, were isolated from the leaves and twigs of Dysoxylum mollissimum B1. Their structures were established by the analyses of spectroscopic data.

中国耳蕨属高山耳蕨组的分类学研究

高山耳蕨组的成员是中国西部、印度北部和喜马拉雅山区常见的蕨类。其成员为夏绿植物，叶片薄而柔弱。秋季叶片枯萎后叶柄基部宿存在地面形成一个丛堆以保护幼芽，这显然是对高山严峻环境的适应。作为高山地带特有类型，１９７２年日本蕨类学家ＳｉｇｅｒｕＤａｉｇｏｂｏ将它们作为耳蕨属下的一个组———高山耳蕨组Ｓｅｃｔ．ＬａｓｉｏｐｏｌｙｓｔｉｃｈｕｍＤａｉｇｏｂｏ，这是合理的。Ｄａｉｇｏｂｏ建立此组时只包含３个种，经过对中国大量标本及有关文献的研究，现知在中国约有３０种应归入此组，其中有３新种：红鳞耳蕨Ｐ．ｒｕｆｏｐａｌｅａｃｅｕｍ，石生耳蕨Ｐ．ｓａｘｉｃｏｌａ，康定耳蕨Ｐ．ｋａｎｇｄｉｎｇｅｎｓｅ；２新变种：裂叶耳蕨Ｐ．ｓｉｎｅｎｓｅｖａｒ．ｌｏｂａｔｕｍ，条裂耳蕨Ｐ．ｍｏｌｉｓｉｍｕｍｖａｒ．ｌａｃｉｎｉａｔｕｍ；１新组合钝裂耳蕨Ｐ．ｉｎｔｅｇｒｉｌｏｂｕｍ（Ｓｏｒｏｌｅｐｉｄｉｕｍ）。据羽片背面的小鳞片类型可将高山耳蕨组划分为２个系：穆坪系Ｓｅｒ．Ｍｏｕｐｉｎｅｎｓｉａ和中华系Ｓｅｒ．Ｓｉｎｅｎｓｉａ。