Essential Oil Constituents from the Fruit of Alpinia menghaiensis

摘要

The chemical composition of volatiles from the fruits of Alpinia menghaiensis S. Q. Tong & Y. M. Xia (Zingiberaceae) has been studied. The essential oils were obtained by hydrodistillation in a Clevenger-type apparatus and analyzed by gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The components of the essential oils were identified by comparison of their mass spectra (MS) data and linear retention indices (LRI) with literature data. The essential oil content was 0.32% (v/w), calculated on a dry weight basis. The fruit oil of A. menghaiensis comprised mainly of compounds of monoterpene represented by β-pinene (40.4%), α-pinene (11.3%) and 1,8-cineole (8.2%). The chemical composition of the essential oil from the fruit of the plant was being reported for the first time. Aims: The objective of the present paper was to report the volatile constituents identified in essential oil of the fruit of Alpinia menghaiensis S. Q. Tong & Y. M. Xia growing in Vietnam. Study Design: The study involves the collection of the fruit samples, hydrodistillation of essential oil from the sample and analyses of the oil sample by means of gas chromatography (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). Place and Duration of Study: Mature fruits of A. menghaiensis were collected from Pù Mát National Park, Nghean Province, Vietnam, in August 2014. Methodology: The hydrodistilled essential oil from the air-dried fruits A. menghaiensis was analysed by means of GC-FID and GC-MS. The constituents were identified by comparison of their mass spectra and retention indices with known data base of authentic samples of essential oil. Co-injection with authentic compounds was also done where necessary. Results: Monoterpene hydrocarbons (68.0%) and oxygenated monoterpene (14.9%) represent the main classes of compounds identified in the oil. The fruit of A. menghaiensis afforded oil whose major compounds were β-pinene (40.4%), a-pinene (11.3%) and 1,8-cineole (8.2%). Conclusion: The high amount of both β-pinene and a-pinene makes the composition of the fruit oil of A. menghaiensis similar to those found for the leaf of A. malaccensis , flower of A. breviligulata , and flower of A. speciosa previously studied from Vietnam. However, there are some other quantitative and qualitative variations between the oil samples. The present result may contribute to the understanding of the chemotaxonomy of Alpinia plants.