Abstract:
The study of fungal antibiotics in their competitive interactions with arthropods may lead to the development of novel biorational insecticides. Extracts of Alternaria tenuissima MFP253011 obtained using various methods showed a wide range of biological activities, including entomotoxic properties. Analysis of their composition and bioactivity allowed us to reveal several known mycotoxins and unidentified compounds that may be involved in the entomotoxic activity of the extracts. Among them, tenuazonic acid (TeA), which was the major component of the A. tenuissima extracts, was found the most likely to have larvicidal activity against Galleria mellonella. In the intrahaemocoel injection bioassay, TeA was toxic to G. mellonella and of Zophobas morio with an LT50 of 6 and 2 days, respectively, at the level of 50 µg/larva. Administered orally, TeA inhibited the growth of G. mellonella larvae and caused mortality of Acheta domesticus adults (LT50 7 days) at a concentration of 250 µg/g of feed. TeA showed weak contact intestinal activity against the two phytophages, Tetranychus urticae and Schizaphis graminum, causing 15% and 27% mortality at a concentration of 1 mg/mL, respectively. TeA was cytotoxic to the Sf9 cell line (IC50 25 µg/mL). Thus, model insects such as G. mellonella could be used for further toxicological characterization of TeA.
摘要:
真菌抗生素与节肢动物竞争性相互作用的研究可能导致新型生物杀虫剂的开发。使用各种方法获得的链格孢菌MFP253011的提取物显示出广泛的生物活性,包括昆虫毒性。对其组成和生物活性的分析使我们能够揭示几种已知的霉菌毒素和未鉴定的化合物,这些化合物可能与提取物的昆虫毒性活性有关。其中,替纽康酸(TeA),这是A.tenuissima提取物的主要成分,被发现是最有可能对海绵铁有杀幼虫活性的。在血液腔内注射生物测定中,TeA对G.melonella和Zophobasmorio有毒,LT50为6天和2天,分别,在50微克/幼虫的水平。口服,在250µg/g饲料的浓度下,TeA抑制了G.mellonella幼虫的生长,并导致Achetadomesticus成虫的死亡(LT507天)。TeA对两种植物毒素表现出弱的接触肠道活动,荨麻疹和五倍子,在浓度为1mg/mL时导致15%和27%的死亡率,分别。TeA对Sf9细胞系具有细胞毒性(IC50为25μg/mL)。因此,模型昆虫,例如G.mellonella可用于进一步的TeA毒理学表征。