現代社會步調快速、文化與科技不斷變革，使人們壓力漸增，其對心靈層面的追求亦日漸提升。即便精神藥物治療可有效解決相關疾病問題或紓緩緊張情緒，但天然方法仍具有一定的效益與需求。臺灣肖楠（Calocedrus macrolepis var. formosana）與臺灣杉（Taiwania cryptomerioides）為珍貴國產林木，可作為工藝、家具、建築等材料，但在撫育或木材收穫後，剩餘的葉子常因無所用途而被丟棄。本研究旨在評估臺灣肖楠與臺灣杉葉子精油做為藥用的可行性。本研究利用氣相層析串聯質譜儀分析臺灣肖楠與臺灣杉葉子精油化學成分，並以嗅吸試驗評估精油對人體情緒之影響。結果顯示，吸聞臺灣肖楠葉子精油能顯著降低受試者沮喪及焦慮情緒；而臺灣杉葉子精油則能顯著降低焦慮情緒。此外，吸聞兩者之葉子精油後，受試者的副交感神經活性皆有所提升。進一步分析兩者之精油成分發現，臺灣肖楠葉子精油主要為α-Pinene及Limonene（分別為72.98%及10.34%），臺灣杉葉子精油主要為α-Pinene、Limonene及3-Carene（分別為14.79%、46.77%及12.22%），顯示此即是賦予臺灣肖楠與臺灣杉葉子精油紓緩情緒效果的成分。由上述結果可知，臺灣肖楠與臺灣杉葉子精油具有開發成為精神相關輔助療法或藥物之潛力。而以臺灣肖楠與臺灣杉葉子作為精油產品在精神紓緩方面的有效利用，亦能使這些剩餘資材成為可永續應用的林業資源。

Stress is increased by rapid social, cultural, and technological changes and mental health issues are more prevalent. Psychotropic medications are effective but so also is immersion in a natural or relaxed situation. Calocedrus macrolepis var. formosana and Taiwania cryptomerioides are valuable plantation woods in Taiwan that are used for crafts, furniture and construction materials, but the leaves of these two woods are usually abandoned. This study determines the feasibility of using the essential oils from their leaves for medicinal purposes. The chemical composition of these essential oils from both the C. macrolepis var. formosana and T. cryptomerioides are identified using gas chromatography-mass spectrometry (GC/MS) and the effects on human emotions of inhaling these essential oils is determined. The results show that inhaling the essential oil from C. macrolepis var. formosana leaves significantly reduces levels of depression/dejection and tension/anxiety. Inhaling the essential oil from T. cryptomerioides leaves also significantly reduces tension/ anxiety. Participants demonstrate significantly higher vagal activity after inhaling both essential oils from C. macrolepis var. formosana and T. cryptomerioides leaves. C. macrolepis var. formosana leaves have significant content of α-pinene and limonene (72.98% and 10.34%) and T. cryptomerioides leaves contain α-pinene, limonene, and 3-carene in (14.79%, 46.77%, and 12.22%), showing their emotion moderating effect is mainly contributed by α-pinene, limonene, and 3-carene. So, the essential oils from these leaves may be an adjuvant to psychotropic medications. This allows the development of sustainable, regenerative forest residues from C. macrolepis var. formosana and T. cryptomerioides leaves.