Studies on the "Hyuga-natsu" a Kind of Summer Orange, Citrus Tamurana

Part IV. Volatile organic acid and terpene constituents of peel oil

Abstract

Essential oils were first extracted with peroxide free ethyl-ether from citrus Hyuga-natsu, recovering by the steam distillation under a reduced pressure. The fractionation into organic acid and terpenes from the oils were carried out as follows. Organic acid fractions were obtained by methylation (diazomethane method) after extraction with NaHCO₃ and terpene by column chromatography, respectively. The components of each fraction were identified by a gas chromatography with the following results.
From the acid fraction formic, acetic, propionic, iso-, n-butyric, iso-valeric, n-caproic, nenanthanic, n-caprylic, n-pelagonic and capric acid were obtained. The dominant acids were acetic and n-caproic occuping nearly 40% of total acids.
From the terpene fraction, α-, β-pinene, myrcene, α-phellandrene, α-, γ-terpinene, p-cymene and d-limonene were identified. α-Limonene was the major constituent.