基于PCR-DGGE技术分析白木香结香前后内生细菌的变化

PCR-DGGE Analysis of Changes of Endophytic Bacteria in Aquilaria sinensis (Lour.) Gilg before and after Agarwood Formation

目的比较结香与未结香白木香内生细菌群落结构及变化,探讨内生细菌在白木香结香过程中的作用。方法分别提取结香与未结香白木香总DNA,采用细菌16s r DNA通用引物进行扩增,聚合酶链反应-变性梯度凝胶电泳(Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis,PCR-DGGE)比较各样品内生细菌群落结构差异,结合样品薄层色谱(TLC)分析,研究活性成分与内生细菌的关联。结果多食鞘氨醇杆菌Sphingobacterium multivorum在未结香白木香中普遍存在。结香后,内生细菌丰富度和多样性明显增加,PCR-DGGE图谱聚类表明,绝大部分结香样品细菌群态相似性较高,聚在一起;非结香样品间的细菌群态相似性也较高。结论白木香结香前后内生细菌群落存在明显差异,内生细菌可能参与白木香的结香过程。

Objective To compare the endophytic bacteria community structure in A quilaria sinensis （L our.） Gilg before and after agarwood formation, and to explore the role of endophytic bacteria in the process of agarwood formation from Aquilaria sinensis. Methods Total DNA was extracted from Aquilaria sinensis separately before and after agarwood formation. With bacterial 16 s rDNA universal primers for amplification and by using polymerase chain reaction and denaturing gradient gel electrophoresis（PCR-DGGE）, we compared the difference of endogenous bacteria structure in the samples. Through thin layer chromatographic analysis, we researched the correlation of active ingredients with endophytic bacteria. Results Sphingobacterium multivorum was wide spread in Aquilaria sinensis before agarwood formation, and after agarwood formation; the richness and diversity of endophytic bacteria were obviously increased. PCR - DGGE graph clustering results showed that most of the bacteria gathered together with higher similarity in most of the Aquilaria sinensis samples with agarwood formation and the bacteria also had higher similarity in the Aquilaria sinensis samples without agarwood formation. Conclusion Obvious difference exists in the endogenous bacteria of Aquilaria sinensis before and after agarwood formation and endophytic bacteria may participate in the process of agarwood formation.