Influence of pH on essential oil composition of Zanthoxylum rhetsa seeds obtained by steam distillation

Effect of extraction methods on the composition of Z. rhetsa seed essential oil was examined. The steam-distilled essential oil from the seeds of Z. rhetsa, obtained under three different conditions were analysed by GC and GC–MS, resulting in the identification of 43 constituents. Sabinene (66.74% and 72.7%), β-pinene (6.47% and 6.59%), α-pinene (6.08% and 6.08%) and myrcene (1.48% and 1.6%) were the major components obtained from aqueous and alkaline media, respectively, while α-terpinene (23.68%), γ-terpinene (23.06%), terpinolene (5.66%) and limonene (4.67%) were the main components from acid medium. Copyright © 2005 John Wiley & Sons, Ltd.