特色香料作物油樟叶内生真菌多样性及其挥发性成分分析

A Study on Diversity and Volatile Components of Endophytic Fungi in Cinnamomum longepaniculatum Leaves

为探究特色香料作物油樟叶内生真菌资源,本研究以5个不同株系油樟在4个季节的叶组织为对象,提取叶部精油,分离纯化叶部可培养内生真菌,采用内转录间隔区(ITS)测序法和多样性指数分析内生真菌丰富度,借助气相色谱/质谱法(GC/MS)鉴定菌株发酵液的挥发性成分。结果表明,不同株系油樟叶产油率在不同季节存在差异,其中春季16号株系油樟叶产油率最高。通过分离纯化共得到43株可培养内生真菌,划分为2门、4纲、9目、11科、13属,优势属为叶点霉属(Phyllosticta)。多样性指数和均匀度分析结果表明,16号株系和春季油樟叶内生真菌种群多样性较丰富,且群落分布相对均匀。GC/MS鉴定结果显示,内生真菌发酵液含有69种主要挥发性成分,其中仅X29、D72和A39能代谢产生油樟叶精油主要成分。可培养内生真菌在不同株系和不同季节的油樟叶中数量、种群及组成均存在差异,筛选得到的功能菌株具有进一步开发香料成分的潜力。本研究结果为后续油樟叶产香料物质的开发研究提供了理论依据与材料。

In order to explore the endophytes fungi of Cinnamomum longepaniculatum,a special spice crop,as subjects,the essential oil of leaves of five Cinnamomum longepaniculatum lines in the four seasons was extracted and cultivatable endophytes were isolated from leaves and purified.Then,the endophyte abundance was analyzed based on the diversity index by using ITS sequencing,and the volatile components of fermentation broth were identified using GC/MS.The results showed that the oil yield of different Cinnamomum longepaniculatum varieties in different seasons were varied,and the oil yield of No.16 in spring was relatively high.A total of 43 cultivatable strains of endophytes were acquired by isolation and purification,and could be divided into two phyla,four classes,nine orders,11 families,and 13 genera;the dominant genus was Phyllosticta.Analysis of diversity and uniformity revealed that the endophyte population diversity and uniformity from variety No.16 in spring were higher than those from other strains.Additionally,69 volatile components were identified in the endophyte fermentation broth by the GC/MS method,wherein X29,D72 and A39 can generate essential oil of Cinnamomum longepaniculatum leaves.The quantity,population and composition of cultivatable endophytes were dependent on the strain and the season',and the identified functional strains show the potential for developing of spice components.The results of this study provide theoretical basis and materials for the subsequent development and research of spice-producing substances.