本研究旨在分析風箱樹 (Cephalanthus naucleoides) 開花時所釋出之揮發化合物,並進一步鑑定貢獻花香的香味活性化合物。試驗分別以固相微萃取 (Solid-phase microextraction, SPME) 及動態頂空採樣 (Dynamic headspace sampling, D-HS) 技術吸附花釋出之揮發化合物,再以氣相層析質譜儀 (Gas chromatography-mass spectrometry,GC-MS) 分析其化學組成,並透過定量分析測定其釋出速率。SPME 的分析結果顯示,風箱樹花所釋出的揮發化合物主要係由trans -β-Ocimene (48.7%)、Linalool (12.6%)、Terpinen-4-ol (4.4%) 及trans-Cinnamyl alcohol (13.0%) 等化合物所組成。由D-HS 的分析結果得知,風箱樹花釋出trans-β-Ocimene、Linalool、Terpinen-4-ol 及trans-Cinnamaldehyde 的速率分別為20.7、15.8、5.8 及14.3μg h^(-1) g^(-1),進一步再配合各揮發化合物的香味閾值,計算三個化合物 (trans -β-Ocimene、Linalool 及trans -Cinnamaldehyde) 的香味強度值, 結果分別為10.2、43.8 及4.8 min-1。綜合上述試驗結果,風箱樹開花時會釋出多種的揮發化合物,包括:trans -β-Ocimene、Linalool、Terpinen-4-ol、trans -Cinnamaldehyde 及trans -Cinnamyl alcohol,其中, 以trans -β-Ocimene 的釋出量最大, 其次為Linalool 及trans -Cinnamaldehyde。本研究證實風箱樹花最主要的香味活性化合物為Linalool,其次為trans -β-Ocimene 及trans -Cinnamaldehyde。
This study analyzes the floral volatile compounds (FVCs) emitted from Cephalanthus naucleoides and identifies the aroma active compounds which contribute to the floral scent. FVCs emitted from flowers were adsorbed using solid-phase microextraction (SPME) and by dynamic headspace sampling (D-HS). The chemical compositions of these compounds were analyzed using gas chromatography-mass spectrometry (GC-MS) and their emission rates were calculated according to quantitative analysis. Results from SPME show that trans- β-ocimene (48.7%), linalool (12.6%), terpinen-4-ol (4.4%) and trans- cinnamyl alcohol (13.0%) were predominant in the FVCs of C. naucleoides. Results from D-HS show that trans- β-ocimene, linalool, terpinen-4-ol and trans- cinnamaldehyde were emitted at the rates of 20.7, 15.8, 5.8 and 14.3 μg h^(-1) g^(-1), respectively. The odor activity values of FVCs were further evaluated and their values were 10.2, 43.8 and 4.8 min-1, respectively. Taken together, C. naucleoides emitted many FVCs, including trans- β-ocimene, linalool, terpinen-4-ol, trans- cinnamaldehyde and trans- cinnamyl alcohol, during full bloom. Among these compounds, trans- β-ocimene was emitted in the largest amount, followed by linalool and trans- cinnamaldehyde. The present study demonstrates that the most active compound for the floral scent was linalool, followed by trans- β-ocimene and trans- cinnamaldehyde.