水茄甲醇提取物对小菜蛾的生物活性与化学成分研究

Natural Products with Bioactivity against Plutella xylostella L.Isolated from Solanum torvum Swartz

为探索外来入侵植物水茄Solarium torvum Swartz的综合利用价值,以小菜蛾为生物活性靶标试虫,在活性跟踪的基础上,综合采用硅胶柱层析、凝胶柱层析、ODS柱层析、聚酰胺层析、HPLC制备等方法对其生物活性成分进行分离,从乙酸乙酯萃取层中分离得到了8个化合物,其中5个为黄酮类化合物,分别是槲皮素(1)、木犀草素(2)、芹菜素(3)、山萘酚(4)和tamarixin(5);3个为生物碱类化合物,分别是N-p-香豆酰酪胺(6)、N-2-hydroxy-2-(p-hydroxyphenylethyl)p-coumaramide(7)和N-(2′-羟基二十四碳酰基)-1,3,4-三羟基-2-氨基-十八烷(8)。其中N-p-香豆酰酪胺和N-2-hydroxy-2-(p-hydroxyphenylethyl)p-coumaramide对小菜蛾2龄幼虫具有显著的毒杀活性,其48 h的LC50值分别为103.5μg/mL和123.1μg/mL。研究为利用水茄中的天然产物成分开发成生物农药提供参考。

The EtOAc-soluble fraction of methanol extract of the whole plant of Solarium torvum Swartz exhibited potent activities against Plutella xylostella L..The fraction was separated using column chromatography（CC） over silica gel,ODS,polyamide polymer,Sephadex LH-20 and HPLC.Five known flavonoids,quercetin（1）,luteolin（2）,apigenin（3）,kaempferol（4）,tamarixin（5）,and 3 known alkaloids, N-trans-p-coumaroyltyramine（6）,N-2-hydroxy-2-（p-hydroxyphenylethyl）p-coumaramide（7）,N-（2＇-hydroxytetra cosyl）-1,3,4-trihydr-oxy-2-amino-octadecane（8）,were isolated by activity-guided fractionation.Compound N-trans-p-coumaroyl tyramine and N-2-hydroxy-2-（p-hydroxyphenylethyl） p-coumaramide exhibited potent toxicities against the 2^（th） instar larvae of P.xylostella.The LC_（50） values were 103.5μg/mL and 123.1μg/mL for 48 h,respectively.The study provided a scientific basis for utilization of S.torvum in development of botanical pesticides.