Abstract Foliar epicuticular waxes of specimens of 13 Croton species native in Brazil were extracted. The fractions containing alkanes and primary alcohols were isolated by preparative thin layer chromatography. Derivatized n-primary alcohols were identified by gas chromatography (GC) coupled with mass spectrometry and n-alkanes by GC and comparison with known standards. Relative abundances were estimated by GC coupled with flame ionization detector. The distribution of constituents of both classes was analyzed by cluster analysis, using the UPGMA method and Euclidean distances. The chemical affinities among species were compared with published data of molecular phylogenetic relationships. The distribution of n-alkanes and primary alcohols were shown to be useful markers of Croton species. Primary alcohols were more consistent than n-alkanes for species fingerprinting.

中文翻译：

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巴豆属（大戟科）叶表皮蜡成分分布的分类学意义

摘要 提取了原产于巴西的 13 种巴豆属植物标本的叶表皮蜡质。通过制备型薄层色谱分离含有烷烃和伯醇的级分。衍生的正伯醇通过气相色谱 (GC) 与质谱联用进行鉴定，正构烷烃通过 GC 进行鉴定，并与已知标准进行比较。相对丰度通过 GC 结合火焰离子化检测器进行估计。使用UPGMA方法和欧几里得距离，通过聚类分析来分析两类成分的分布。将物种之间的化学亲和力与已发表的分子系统发育关系数据进行比较。正构烷烃和伯醇的分布被证明是巴豆物种的有用标记。