烤烟种子中有机酸的气相色谱法分析及聚类分析

Analysis of Organic Acids in Flue-cured Tobacco Seeds by Gas Chromatography and Cluster Analysis

建立了气相色谱法测定烤烟种子8种有机酸的方法。烤烟种子中的有机酸用10%的硫酸-甲醇（v/v）溶液衍生化为甲酯,经二氯甲烷萃取后,用气相色谱（FID）测定其含量。结果表明,该方法相关系数为0.9991～0.9998,回收率为98.6%～100.9%,相对标准偏差小于3.3%,采用此方法测定了13份烤烟种子中8种有机酸的含量,并进行聚类分析,亚油酸是烤烟中含量最高的脂肪酸,其次是油酸、棕榈酸、柠檬酸。13份样品可以聚为4类,8种有机酸的含量分布特征能反映不同烤烟种子的特性,对种子的分类具有一定的参考价值。

A method for the determination of 8 organic acids in flue-cured tobacco seeds with gas chromatography was developed. Samples were derivatizated by 10 % sulfuric acid-methanol（ v / v）,extracted by dichloromethane,determined by gas chromatography（ FID） detector. It was found that the recoveries of the method was between 98. 6 % and 100. 9 %,the relative standard deviation was equal or less than3. 3 %,the correlation coefficients of linear regression equations were from 0. 9991 to 0. 9998. The content of 8 organic acids in 13 tobacco seeds samples were determined with this method,and the data were processed with cluster analysis. Results showed that the 13 samples could be classified into 4 classes,the proportion distribution of 8 organic acids reflected clearly the characteristics of different flue-cured tobacco seeds,which could be served as a reference in tobacco seeds classification.