Institute of Plant and Environmental Protection, Beijing Academy of Agricultural and Forestry Science , Beijing 100097, China.
Mycology and Nematology Genetic Diversity and Biology Laboratory, Agricultural Research Service, U.S. Department of Agriculture , Building 010A, 10300 Baltimore Avenue, Beltsville, Maryland 20705, United States.
J Agric Food Chem. 2017 Apr 19;65(15):3127-3132. doi: 10.1021/acs.jafc.6b04353. Epub 2017 Apr 5.
Chemical investigation of the fungal strain Gymnoascus reessii za-130, which was previously isolated from the rhizosphere of tomato plants infected by the root-knot nematode Meloidogyne incognita, led to the isolation and identification of a new indoloditerpenoid metabolite designated gymnoascole acetate. Its structure was established by spectroscopic methods including 1D- and 2D-NMR and MS analyses. Gymnoascole acetate demonstrated strong adverse effects on M. incognita second-stage juvenile (J2) viability; exposure to 36 μg/mL for 24 h induced 100% paralysis of J2 (EC = 47.5 μg/mL). Gymnoascole acetate suppressed M. incognita egg hatch relative to controls by >90% at 133 μg/mL after 7 days of exposure. The numbers of root galls and J2 in both soil and roots were significantly reduced (p = 0.05) by treatment with 2-200 μg/mL gymnoascole acetate/kg soil, compared to untreated control plants; nematode suppression increased with gymnoascole acetate concentration. This study demonstrated the nematotoxicity of gymnoascole acetate and indicates that it might be a potential biobased component in integrated management of M. incognita.
从感染根结线虫的番茄根际土壤中分离到的真菌菌株 Gymnoascus reessii za-130 的化学成分研究，导致了一种新的吲哚二萜代谢物的分离和鉴定，命名为 gymnoascole 乙酸酯。其结构通过包括 1D-和 2D-NMR 和 MS 分析在内的光谱方法确定。Gymnoascole 乙酸酯对根结线虫第二阶段幼虫（J2）的存活有很强的不良影响；暴露于 36 μg/mL 24 h 诱导 J2 100%瘫痪（EC = 47.5 μg/mL）。暴露 7 天后，gymnoascole 乙酸酯在 133 μg/mL 时对卵孵化的抑制率超过 90%，而对照处理组则超过 90%。与未处理的对照植物相比，用 2-200 μg/mL gymnoascole 乙酸酯/kg 土壤处理可显著减少土壤和根中根瘤和 J2 的数量（p = 0.05）；随着 gymnoascole 乙酸酯浓度的增加，线虫抑制作用也随之增加。本研究证明了 gymnoascole 乙酸酯的杀线虫活性，并表明它可能是综合治理根结线虫的潜在生物基成分。
