Department of Ecophysiology, Institute of Cellular and Molecular Botany, University of Bonn, Bonn, Germany.
Methods Mol Biol. 2021;2295:275-293. doi: 10.1007/978-1-0716-1362-7_15.
Extracellular lipids of plants can be analyzed using gas chromatography and mass spectrometry. Soluble waxes are extracted with chloroform and thus separated from the extracellular polymers cutin and suberin. Cutin and suberin have to be depolymerized using boron trifluoride-methanol or methanolic HCl before analysis. The released monomeric hydroxylated fatty acids are then extracted with chloroform or hexane. Prior to gas chromatography, all free polar functional groups (alcohols and carboxylic acids) are derivatized by trimethylsilylation. Internal standards, that is, long chain alkanes, are used for the quantification of wax molecules and cutin or suberin monomers. Lipids are quantified using gas chromatography coupled to flame ionization detection. Qualitative analysis is carried out by gas chromatography coupled to mass spectrometry. Thus, all wax molecules of chain lengths from C to C and different substance classes (fatty acids, alcohols, esters, aldehydes, alkanes, etc.) or all cutin or suberin monomers of chain lengths from C to C and different substance classes (hydroxylated fatty acids, diacids, etc.) can be analyzed from one sample.
植物的细胞外脂质可以使用气相色谱和质谱分析。使用氯仿提取可溶性蜡，从而将其与细胞外聚合物角质和栓质分离。在分析之前，必须使用三氟化硼-甲醇或甲醇盐酸将角质和栓质解聚。然后用氯仿或己烷提取释放的单体羟基脂肪酸。在进行气相色谱分析之前，所有游离的极性官能团（醇和羧酸）都通过三甲基硅烷基化进行衍生化。使用内标，即长链烷烃，对蜡分子和角质或栓质单体进行定量。使用气相色谱法结合火焰离子化检测进行脂质定量。通过气相色谱法结合质谱进行定性分析。因此，可以从一个样品中分析出链长从 C 到 C 的所有蜡分子和不同物质类别（脂肪酸、醇、酯、醛、烷烃等），或链长从 C 到 C 的所有角质或栓质单体和不同物质类别（羟基脂肪酸、二酸等）。
