对采自青海 10 个居群的小秦艽(Gentiana dahurica Fischer)根部游离脂肪酸的组成及相对含量进行了测定,并利用主成分分析方法对脂肪酸主成分的分布特征进行了研究并分析了脂肪酸主成分与生态因子的相关性。 结果表明,小秦艽根部含有 22 种游离脂肪酸,部分脂肪酸成分的相对含量较高,且高含量脂肪酸多为偶数高碳脂肪酸,其中 C₁₆和 C₂₆脂肪酸的平均相对含量分别高达 42. 102 和 74. 029 μg· g ^{- 1} 。 主成分分析结果表明,前 4 个主成分的累积贡献率达到 81. 325% ,以偶数高碳脂肪酸成分的负荷量最大,可基本反映小秦艽根部脂肪酸成分的分布特征。 相关分析结果显示,小秦艽根部脂肪酸含量具有地理分布差异,第 1 主成分与日照时间显著负相关 ( P <0. 05),第 3 主成分与海拔高度显著正相关 ( P < 0. 05),表明海拔越高、日照时间越短,小秦艽根部脂肪酸含量越高,揭示出小秦艽在高原生境条件下对逆境干旱环境的部分生理适应机制。

 

The components and relative content of free fatty acids in Gentiana dahurica Fischer root from ten populations in Qinghai Province were determined, and the distribution characteristics of fatty acid principal components were studied by the principal component analysis, then the correlation of fatty acid principal components with ecological factors was analyzed. The results show that twenty-two free fatty acids are detected from G. dahurica root, and relative contents of some of those are higher. Most fatty acids with higher relative content are long-chain fatty acids with an even number of carbon atoms. The average relative content of C₁₆ and C₂₆ fatty acids is up to 42. 102 and 74. 029 μg· g ^{- 1}, respectively. The result of principal component analysis reflects the distribution characteristics of fatty acids in G.dahurica root. The cumulative contribution rate of the first four principal components is 81. 325% , in which loadings of long-chain fatty acids with an even number of carbon atoms are bigger. The correlation analysis shows that there is geographical difference regarding fatty acid content in G. dahurica root. The first principal component has a significant negative correlation (P < 0. 05) with the sunshine time, while the third principal component has a significant positive correlation (P < 0. 05) with the altitude, that is, the higher the altitude and the longer the sunshine time, the higher the contents of fatty acids are, and partial anti-aridity physiological adaptation of G. dahurica in plateau environment is revealed.