Aroma-active compounds of leaf extracts from Khingan fir, manchurian fir, and red pine

Abstract

Aroma-active compounds in the needles of Abies nephrolepis (Khingan fir), Abies holophylla (Manchurian fir), and Pinus densiflora (red pine), conifers native to Korea, were analyzed by gas chromatography-mass spctormetry-olfactometry. Gas chromatography-mass spectrometry revealed that terpene compounds were found to account for over 95% of total volatile compounds, especially, monoterpenes were contained a large percentage in these conifers. Aroma extract dilution analysis using two types of capillary column with different polarities (DB-5MS and DB-WAX) revealed that α-pinene was the most predominant aroma-active compound with pine-like aroma, which indicates that α-pinene contribute the typical conifer aroma to the plants. Also, bornyl acetate, myrcene, β-phellandrene, γ-terpinene, and terpinolene were found to show typical pine-like aromas. When the overall aroma of A. nephrolepis was compared with A. holophylla, considerable differences were observed. A. nephrolepis was judged to emit a intenser apple-like aroma due to (Z)-3-hexenal and (Ε)-2-hexenal, while A. holophylla had a sharper pine-like aroma, which is affected by the terpene compounds showing sharp or pine-like aroma, such as myrcene, 4-terpineol, geranyl actate, and β-caryophyllene. In Pinus densiflora which has typical conifer aroma, α-pinene, (Ζ)-3-hexenal, and bornyl acetate were found to be the important aroma contributors.