杨梅叶挥发油的季节变化规律及其药用价值分析

目的: 分析不同季节杨梅叶挥发油(Myrica rubra leaves volatile oils,MVO)的化学成分变化规律,探讨其抗癌抑菌等生物活性及药用价值. 方法: 通过水蒸气蒸馏法提取挥发油,利用GC-MS技术表征挥发油的季节差异性,并通过MTT法分析对人肺癌细胞A549增殖抑制作用,琼脂扩散法分析对6种细菌的抑菌活性. 结果: 春、夏、秋和冬四季杨梅叶挥发油提取得率为每100 g 0.09~0.13 mL,分别鉴定出39、30、28和41种成分,其中有16种萜烯、醇、醛、酮、酸和酯类物质存在于所有的叶片中.β-石竹烯和α-葎草烯是杨梅叶挥发油的主要成分,β-石竹烯含量的季节变化规律为冬季(43%)> 春季(28.9%)> 秋季(22.9%)> 夏季(19.02%),α-葎草烯含量的季节变化规律为秋季(39.8%)> 春季(31.5%)> 冬季(26.02%)> 夏季(25.1%).另外挥发油中含量超过15%的成分有秋季挥发油中的γ-雪松烯和夏季挥发油中的喇叭烯氧化物-(Ⅱ),此2种成分在不同的季节中含量变化差异显著,氧化石竹烯含量在春冬两季含量大于4%,秋季未检出,除此以外其他成分含量均较低.MTT实验结果表明,杨梅叶挥发油对细胞A549增殖的抑制随作用时间增加而增强,且冬季挥发油对肿瘤细胞具有较强的细胞毒活性.抑菌实验表明杨梅叶挥发油对革兰氏阳性菌的抑制作用强于对革兰氏阴性菌,而冬季挥发油抑菌效果强于其他3个季节,对变形杆菌和沙门氏菌的抑制能力较弱. 结论: 杨梅叶挥发油具有抑菌、抗癌等药物开发前景,且在冬季杨梅叶挥发油作用最为显著.

Objective: To determine the variability of chemical compositions in volatile oils of Myrica rubra leaves(MVO) collected over an annual cycle (spring,summer,autumn,and winter),and evaluate the bacteriostatic & anticancer bioactivities and medicinal value. Methods: The volatile oils were extracted from leaves of Myrica rubra by the steam distillation,and analyzed by GC-MS.Meanwhile,its inhibitory effects on the proliferation of human lung cancer cell line A549 and growth of six kinds of bacteria (Staphylococcus aureus,Bacillus subtilis,and so on) were detected by MTT assay and agar diffusion method. Results: The extraction rate of MVO in spring,summer,autumn and winter was in the range of 0.09-0.13 mL per 100 g.39,30,28 and 41 volatile compounds of MVO were identified in samples of spring,summer,autumn and winter,respectively.Sixteen compounds of these including terpenes,alcohols,aldehydes,ketones,acids and esters were found in all leave samples regardless of the season.Among all seasonal volatiles,β-caryophyllene and α-humulene predominated in MVO.Specifically,the concentrations of β-caryophyllene and α-humulene were in the following order from the highest to the lowest:winter (43%)> spring (28.9%)> autumn (22.9%)> summer (19.02%),and autumn (39.8%)> spring (31.5%)> winter (26.02%)> summer (25.1%),respectively.The contents of γ-cedrene and hornene oxide-(Ⅱ) were more than 15% in both winter and summer MVO.However,caryophyllene oxide was only found in spring and winter MVO,and its content was more than 4%.Other components were all found in low levels.The results of MTT assay showed that MVO displayed significant inhibitory effects on A549 cell proliferation with the increase of processing time.Furthermore,the winter MVO exhibited strong anticancer and antibacterial effects. Conclusion: Myrica rubra leaves volatile oils displayed remarkable application prospect as potential anticancer drugs and antimicrobial agents.In addition,the performance of winter MVO is the most effective.