烟叶表面蜡质非极性和弱极性成分的分离鉴定及保润性能

Hydrophobie Composition of the Surface Wax from Tobacco: Separation, Identification and Moisture Retentivity of Cut Tobacco

摘要: 建立了一套适宜烟叶表面蜡质提取和气相色谱–质谱联用(GC-MS)分离、鉴定的方法。以甲基叔丁基醚–甲醇混合溶液(9 + 1, v/v)提取烟叶表面蜡质成分，然后通过硅胶固相萃取方法进行族分离，将表面蜡质提取物分为非极性、弱极性和极性3个馏分，再进行GC-MS分析。从烟叶表面蜡质的提取物中共分离和鉴定出26种烷烃和12种烷醇；比较了表面蜡质各组分的相对含量，其中主要成分是烷烃，占分离物质总量的61.4%。烷烃中主要是C16~nC34的正构烷烃，含量较高的是正三十一烷和正二十七烷；含量最高的烷醇为二十二烷醇，其次是二十烷醇，两种烷醇在馏分II中的相对含量分别为62.5%和20.6%；烷醇表现出偶数碳优势的特征。烟丝保润性能研究结果表明，将烷烃及烷醇等烟叶蜡质主要成分喷至烟丝表面，烟丝的失水量均小于对照样，表明烷烃及烷醇类物质对烟丝的保润性能均有一定程度的改善作用。

Abstract: This study established a novel separation and identification method for wax extration from to-bacco leaf surface using gas chromatography-mass spectrometry (GC-MS). Specifically, we ex-tracted the constituent of tobacco leaf surface wax with methyl tert-butyl ether and methanol mixture (9 + 1, v/v), followed by family separation using the silica gel solid-phase extraction method. Surface wax extract was then divided into surface wax extract nonpolar, weak polarity, and polarity, followed by GC-MS analysis. Using this method, we determined the composition of wax extracts from tobacco leaf surface in China. We separated and identified 26 different kinds of alkanes and 12 alkyl alcohol. Among them, alkane is th emost abundant, accounting for 61.4% of the total separation material. Among alkanes, most of which are C16~nC34 alkanes, i31 alkanes and 27 alkanes are the most rebundant; The highest levels of alkyl alcohol as docosanoic alcohol, followed by 20 alkoxide, the content of the two compounds in the fractions II relative content was 62.5% and 20.6%, respectively. The alkyl alcohols show the characteristics of the even carbon advantage. The alkanes and alkanol were selected for the moisture retention test to evaluate the moisturizing property of cut tobacco in low humidity environment. Our results showed that both alkanes and alkanol could improve retain moisture properties of cut tobacco.