不同树龄梁平柚果皮精油挥发性成分的差异分析

为探索重庆梁平地区不同树龄的梁平柚果皮精油挥发性成分组成和含量的差异性,采用顶空固相微萃取法结合气相色谱-质谱联用分析鉴定5个不同树龄梁平柚皮精油,并利用偏最小二乘法判别分析和凝聚层级聚类分析对其挥发性成分进行统计分析并找出特征挥发性成分。结果表明:5个不同树龄梁平柚皮精油共分离鉴定出72种挥发性化学成分,其中d-柠檬烯、β-月桂烯、圆柚酮等8种成分相对含量较高(>1%),共占总挥发性成分的83.40%~87.61%;HCA分析法将5个不同树龄段梁平柚皮精油聚类为3类,结合PLS-DA分析结果得出E-2-已烯-1-醇、大根香叶烯B、L-薄荷醇等21个挥发性成分为3类精油的特征性挥发物质。研究结果同时发现不同树龄段梁平柚果皮精油挥发性成分的组成具有一定差异性,呈现出不同的香型特征,这为梁平柚果皮精油差异化开发应用提供了理论参考。

Difference Analysis of Volatile Components of Essential Oil of Liangping Pomelo Peel with Different Tree Ages

In order to investigate the difference in the essential oil composition and content of Liangping pomelo with tree ages in Liangping,headspace solid-phase microextraction(HS-SPME)and gas chromatography-mass spectrometry(GC-MS)detection technology were applied to identify the essential oils of Liangping pomelo peel with 5 different tree ages.The effects of tree ages on the types and quantities of volatile components in the essential oils were compared.Partial least squares discrimination analysis(PLS-DA)and hierarchical cluster analysis were adopted to analyze the volatile components of pomelo peel essential oil of 5 different tree ages.The results showed that 72 volatile constituents were isolated and identified from the essential oils of Liangping pomelo peel with 5 different tree ages.The relative contents of 8 constituents(such as d-limonene,beta-lauryl,naringone,etc.)were higher(relative content>1%)and accounted for 83.40%~87.61%of the total volatile constituents.The essential oils of Liangping pomelo peel at five different tree ages were clustered into three groups by HCA analysis.The analysis of PLS-DA showed that 21 volatile components,such as E-2-hexene-1-ol,geranine B and L-menthol,were the characteristic volatile components of the three kinds of essential oils.The results showed that the volatile components of Liangping pomelo peel essential oil at different tree ages were different and showed different aroma characteristics,which provided a theoretical reference for the differential development and application of Liangping pomelo peel essential oil.