牛至挥发油的化学成分及其化感作用

Chemical composition and allelopathic potential of essential oil isolated from Origanum vulgare

为探究牛至挥发油的化学成分及其化感作用,本文采用水蒸气蒸馏法提取牛至全草挥发油,利用气相色谱(GC)和气相色谱-质谱联用(GC-MS)从牛至挥发油中鉴定出14种化学成分,占总出峰面积的93.6%,主要成分为甲基丁香酚(16.5%)、肉豆蔻醚(15.6%)、香芹酚(15.0%)、百里香酚(9.8%)、洋芹脑(9.4%)等。通过测定挥发油对小麦、绿豆和萝卜种子萌发及幼苗生长的影响,评价挥发油的化感潜力。结果表明:牛至挥发油对3种受体植物的种子萌发有抑制作用,其中,对小麦的抑制作用最强,萝卜和绿豆次之,挥发油对供试植物地上部分生长的抑制作用大于地下部分。挥发油对3种供试植物幼茎及小麦和萝卜幼根生长的抑制作用与浓度成正相关,对绿豆幼根长度则表现为"低促高抑"现象。本研究证实牛至挥发油中含有化感物质,其活性化合物及作用机制有待进一步研究。

This study aimed to explore the chemical composition of essential oil isolated from Origanum vulgare and investigated its allelopathic potential.The essential oil isolated by hydro-distillation from the whole plant of O.vulgare was analyzed by GC and GC-MS.Fourteen different components were identified,constituting 93.56%of the total area of peaks.The major components were methyleugenol(16.5%),myristicin(15.6%),carvacrol(15.0%),thymol(9.8%),and apioline(9.4%).We examined the inhibitory effects of essential oil on seed germination and seedling growth of wheat(Triticum aestivum),mung bean(Vigna radiata),and radish(Raphanus sativus).The results showed that essential oil of O.vulgare inhibited seed germination of all tested crops,with wheat being the most susceptible,followed by radish and mung bean.The inhibitory effects of essential oil on growth of the aboveground part of tested crops were greater than that of underground part.The inhibitory effects of essential oil on the seedling length of all tested crops increased in a dose-dependent manner,with the same pattern for radicle length of wheat and radish as well.Meanwhile,essential oil could stimulate radicle growth of V.radiata at low concentration,but inhibit the growth at high concentration.Our results confirmed the existence of allelochemicals in the essential oil of O.vulgare.However,what the compounds will be and how about their allelopathic mechanism needs further investigation.