不同采收期单叶蔓荆子挥发油成分的分析比较

采用水蒸气蒸馏法提取不同采收时期(早、中、晚)的单叶蔓荆子挥发油,得率分别为0.35%、0.41%和0.39%。气相色谱-质谱联用分析结果表明:从3种采收期蔓荆子挥发油中分别分离鉴定得到19、22和29种成分;虽然仅有5种相同成分:1,8-桉油精(1,8-环氧对薄荷烷)、反-水合桧烯、β-葑基乙醇、β-荜澄茄油烯和τ-萘醇等(在早、中、晚期样中这5种成分总质量分数分别为13.778%、12.871%和15.097%),但主体成分均为单萜及倍半萜类化合物(3个时期样中的质量分数分别为99.6%、90.2%和94.1%)。不同采收期的蔓荆子挥发油主要成分各有特征:早期呈高蒎烷型,中期呈高乙酰氧基-对-薄荷烷型,晚期呈高对-薄荷烷(二烯)型;具代表性的首要成分分别为α-蒎烯(34.994%)、1-乙酰氧基-对-薄荷烷-4(8)-烯(63.943%)和dl-柠檬烯(4-薄荷烷-1,8-二烯,31.819%)。早期挥发油中质量分数较高的还有1-乙酰氧基-对-薄荷烷-4(8)-烯(22.972%)、β-水芹烯(10.753%)、1,8-桉油精(8.151%)和桧烯(7.842%)等,而晚期有β-蒎烯(15.798%)、β-石竹烯(10.043%)和1,8-桉油精(5.927%)。此外,中期出现4种脂肪族化合物(占总质量的6.08%);晚期不含有1-乙酰氧基-对-薄荷烷-4(8)-烯,而出现一些沸点较高的三环倍半萜类如δ-古芸烯(3.584%)、β-荜澄茄油烯(6.774%)。

Comparison of Chemical Constituents of the Essential Oil from Fructus Viticis during Different Harvesting Time

The effects of different harvesting time under the same habitat on the chemical constituents of essential oil obtained by steam distillation from fructus viticis,which were the dried fruits of Vitex trifolia Linne var.simplicifolia Cham.(synonym:V.rotundifolia Linne fil.),were studied.The essential oil contents were 0.35 %,0.41 %,and 0.39 % during different harvesting time,namely Aug.,Sep.and Oct.respectively.According to the order of the harvesting time,19,22 and 29 compounds in the different essential oils were detected by GC-MS,respectively,but only 5 compounds in three different essential oils are in common.The main compounds in all essential oils were terpenoids,whose contents were 99.6 %,90.2 % and 94.1 %,respectively.This result implies that most of the chemical constituents among three different essential oils were different.On the other hand,the types of three main terpenoids were pinanes,acetoxy-p-menthanes,and p-menthane-diene during the three different harvesting times, respectively.These chemical types have similar structures that will be used for further investigating their interrelation in fructus viticis in order to optimize its quality.