微杆菌Sneb159杀线虫活性物质的分离与鉴定

Isolation and identification of nematicidal compound from Microbacterium maritypicum Sneb159

【目的】有关Microbacterium maritypicum在植物线虫生物防治方面的研究较少,探究菌株M.maritypicum Sneb159的杀线虫活性,明确菌株发酵液中具有杀线虫活性的物质,为生物农药的开发提供理论依据。【方法】本研究检测了菌株Sneb159发酵液对大豆胞囊线虫二龄幼虫的触杀活性;并以触杀活性为追踪,采用有机溶剂萃取、硅胶柱层析及半制备高效液相色谱等技术对菌株Sneb159发酵滤液中的活性物质进行分离纯化;采用核磁共振波谱对纯化物进行结构鉴定。【结果】菌株Sneb159具有杀线虫活性,在24 h和48 h处理组中线虫的死亡率均显著高于对照组。从菌株Sneb159发酵滤液中分离得到杀线虫活性物质A6,经结构鉴定确定该物质为苯乙酰胺。【结论】首次发现M.maritypicum对大豆胞囊线虫的触杀作用,并且明确活性物质为苯乙酰胺。结果表明菌株M.maritypicum Sneb159和苯乙酰胺在大豆胞囊线虫的生物防治方面具有较好的应用潜力。

[Objective] Few studies have been reported about the biological control of plant parasitic nematodes by Microbacterium maritypicum. The purpose of this study was to determine the nematicidal activity of M. maritypicum Sneb159. In addition, nematicidal active compounds were separated from the culture supernatant of strain Sneb159. The study will provide fundamental knowledge about the development of biological pesticides. [Methods] We evaluated the direct antagonism to the second-stage juveniles(J2s) of Heterodera glycines in vitro. The nematicidal compound was separated and purified from culture supernatant of strain Sneb159 using organic solvent extraction, followed by silica gel chromatography and semi preparative high performance liquid chromatography according to the mortality of J2s. We characterized the compound by nuclear magnetic resonance spectrum. [Results] Strain Sneb159 showed strong nematicidal activity. The mortality of H. glycines J2s in Sneb159 treatment was significantly higher than that in the control after 24 h and 48 h incubation. One active compound, phenylacetamide, was obtained from culture supernatant of strain Sneb159. [Conclusion] To our knowledge, this is the first report to describe the nematicidal activity of M. maritypicum against H. glycines. The results suggested that strain Sneb159 and phenylacetamide have potential applications for biological control of H. glycines.