DST Unit on Nanoscience and Thematic Unit of Excellence, Department of Chemistry, Indian Institute of Technology Madras, Chennai, India.
J Agric Food Chem. 2013 Aug 7;61(31):7477-87. doi: 10.1021/jf4011998. Epub 2013 Jul 26.
The difference in size, shape, and chemical cues of leaves and flowers display the underlying genetic makeup and their interactions with the environment. The need to understand the molecular signatures of these fragile plant surfaces is illustrated with a model plant, Madagascar periwinkle (Catharanthus roseus (L.) G. Don). Flat, thin layer chromatographic imprints of leaves/petals were imaged using desorption electrospray ionization mass spectrometry (DESI MS), and the results were compared with electrospray ionization mass spectrometry (ESI MS) of their extracts. Tandem mass spectrometry with DESI and ESI, in conjunction with database records, confirmed the molecular species. This protocol has been extended to other plants. Implications of this study in identifying varietal differences, toxic metabolite production, changes in metabolites during growth, pest/pathogen attack, and natural stresses are shown with illustrations. The possibility to image subtle features like eye color of petals, leaf vacuole, leaf margin, and veins is demonstrated.
叶片和花朵在大小、形状和化学特征上的差异显示了其潜在的遗传构成以及它们与环境的相互作用。为了了解这些脆弱植物表面的分子特征，以模式植物马达加斯加长春花（Catharanthus roseus（L.）G. Don）为例进行了说明。使用解吸电喷雾电离质谱（DESI MS）对叶片/花瓣的扁平、薄层色谱印痕进行成像，并将结果与它们的提取物的电喷雾电离质谱（ESI MS）进行比较。DESI 和 ESI 的串联质谱分析，结合数据库记录，确认了分子种类。该方案已扩展到其他植物。本研究在鉴定品种差异、有毒代谢产物的产生、生长过程中代谢物的变化、害虫/病原体的攻击以及自然胁迫方面的应用，通过实例进行了说明。还演示了对花瓣眼斑颜色、叶液泡、叶缘和叶脉等细微特征进行成像的可能性。
