Investigation of volatile organic compounds from important plantation tree species in Taiwan

Terpenes constitute the largest class of plant secondary metabolites, which are compounds of ecological function in plant defense or the attraction of beneficial organisms. In this study, essential oils and fragrance compositions extracted from the leaves of Cinnamomum camphora (L.) J. Presl, Fraxinus griffithii C.B. Clarke and Liquidambar formosana were analyzed. Chemical diversity was observed, the components of essential oils and fragrant compounds with some species-specific and could be used to discriminate these species in PCA plot. Camphor constitute the major component of both essential oil and fragrance composition of C. camphora leaf , while F. griffithii primarily contained Linalool and α-Terpineol; Terpinen-4-ol and Sabinene were the characteristic compounds belong to L. formosana. As to the fragrant compounds of these three species, were studied by solid-phase micro-extraction and GC/MS. The major aroma compounds were: Camphor (78.06% - 80.37%), β-Caryophyllene (8.17% - 9.23%)、Limonene (1.00% - 2.46%) and Linalool (1.07% - 1.38%) in C. camphora; (E)-2-Hexenal (30.62% – 56.36%), Limonene (5.38% - 16.97%), p-Cymene (3.04% - 11.21%), (Z)-2-Hexen-1-ol (3.41% - 7.52%), and Terpinen-4-ol (4.46% - 7.23%) in F. griffithii; Sabinene (43.41% - 54.17%), Terpinen-4-ol (12.40% - 22.79%)、γ-Terpinene (6.01% - 7.36%), cis-Sabinenhydrate (3.89% - 6.40%), and Linalool (2.93% - 5.08%) in L. formosana; The results may provide useful information for future studies on volatile identification and chemotaxonomy.

萜类（Terpenes）是植物次生代谢产物中规模最大的一类，在植物防御或吸引有益生物过程中发挥生态功能。本研究对樟（Cinnamomum camphora (L.) J. Presl）、格里菲思梣（Fraxinus griffithii C.B. Clarke）和枫香树（Liquidambar formosana）的叶片提取物——精油（essential oils）与香气成分（fragrance compositions）——进行了分析。研究观察到其化学成分具有多样性，精油与香气成分的组成存在一定的物种特异性，可通过主成分分析（PCA）图对这三个物种进行区分。樟叶片的精油与香气成分均以樟脑（Camphor）为主要组分；格里菲思梣的主要香气成分则为芳樟醇（Linalool）和α-松油醇（α-Terpineol）；而枫香树的特征成分为4-松油醇（Terpinen-4-ol）和桧烯（Sabinene）。本研究采用固相微萃取（solid-phase micro-extraction）结合气相色谱-质谱联用（GC/MS）技术，对这三个物种的香气成分进行了分析：樟的主要香气成分为樟脑（78.06%~80.37%）、β-石竹烯（β-Caryophyllene，8.17%~9.23%）、柠檬烯（Limonene，1.00%~2.46%）以及芳樟醇（1.07%~1.38%）；格里菲思梣的主要香气成分为(E)-2-己烯醛（(E)-2-Hexenal，30.62%~56.36%）、柠檬烯（5.38%~16.97%）、对伞花烃（p-Cymene，3.04%~11.21%）、(Z)-2-己烯-1-醇（(Z)-2-Hexen-1-ol，3.41%~7.52%）以及4-松油醇（4.46%~7.23%）；枫香树的主要香气成分为桧烯（43.41%~54.17%）、4-松油醇（12.40%~22.79%）、γ-松油烯（γ-Terpinene，6.01%~7.36%）、顺式桧烯水合物（cis-Sabinenhydrate，3.89%~6.40%）以及芳樟醇（2.93%~5.08%）。本研究结果可为后续挥发性成分鉴定及化学分类学相关研究提供参考依据。