两种桉叶挥发油含量和化学成分周年变化

Annual Change of Contents and Their Chemical Compositions of Essential Oils from Leaves of E.exserta and E.urophylla

摘要:

为了探索窿缘桉和尾叶桉叶挥发油含量和化学成分的周年变化规律，采用水蒸气蒸馏法提取其挥发油，采用GC-MS法分析挥发油化学成分，并以挥发油提取率为指标，确定桉叶的最佳采收期。结果表明，窿缘桉叶挥发油含量周年变化显著，5、9、10月份含量最高，为最佳采收期；尾叶桉挥发油含量周年变化较小，4、5、7月份含量相对较高，适宜采收。窿缘桉叶挥发油主要成分为α-蒎烯、β-蒎烯、桉树脑，含量变化显著。尾叶桉叶挥发油主要成分为α-蒎烯、桉树脑、冰片和α-松油醇，含量变化显著。不同时期桉叶挥发油化学成分含量有很大的差异。

Abstract:

In order to explore the annual change of essential oils contents and their chemical compositions from the leaves of E.exserta and E.urophylla, the essential oils were extracted in different months with steam distillation respectively and their chemical compositions were determined with GC-MS. The best harvest time of the essential oils were confirmed according the extraction ratio of the essential oils. The results showed that the extraction yied of essential oils from the leaves of E.exserta showed a significant seasonal change while the essential oils from E.urophylla did not. The extraction yield of essential oils from E.exserta in May, September and October were relatively higher and the leaves of these months were suited for extracting essential oils. The major compositions of the essential oils from E.exserta were α-pinene, β-pinene, eucalyptol and the major constituents of essential oil from E.urophylla were α-pinene, eucalyptol, borneol, α-Terpineol. The content of major compositions in each month varied considerably.