Rochfort Simone J, Trenerry V Craige, Imsic Michael, Panozzo Joe, Jones Rod
Department of Primary Industries - Werribee Center, 621 Sneydes Road, Werribee, Victoria 3030, Australia.
Phytochemistry. 2008 May;69(8):1671-9. doi: 10.1016/j.phytochem.2008.02.010. Epub 2008 Apr 8.
Glucosinolates are naturally occurring anionic secondary plant metabolites incorporating a thioglucosidic link to the carbon of a sulphonated oxime. There are a large number of naturally occurring glucosinolates and they are found in relatively large quantities in many plant species within the family Crucifereae. These metabolites are of interest for both their anticancer and flavour properties and in the study of nitrogen and sulphur metabolism in model plants such as Arabidopsis. Parent ion mapping is an analytical mass spectrometry approach that allows rapid assessment of glucosinolate content. Ion mapping proved to be highly sensitive and the glucosinolate sinigrin could be detected at three parts per trillion. This method takes advantage of the glucosinolate anion fragmentation which consistently produces a sulphonate ring-opened glucose moiety in the ion trap mass spectrometer, m/z 259. An intramolecular transfer mechanism for this fragmentation is presented here for the first time. This fragmentation can be exploited as a general identifier of the glucosinolate class of metabolites in plant extracts and in LCMSn can be employed provide positive identification and quantification of individual glucosinolates. Such approaches offer sensitive tools for focused metabolomics analysis and screening of plant breeding lines.
硫代葡萄糖苷是天然存在的阴离子型次生植物代谢产物，其硫代葡萄糖苷键连接到磺化肟的碳原子上。天然存在的硫代葡萄糖苷种类繁多，在十字花科的许多植物物种中含量相对较高。这些代谢产物因其抗癌和风味特性以及在拟南芥等模式植物的氮和硫代谢研究中而备受关注。母离子图谱分析是一种分析质谱方法，可快速评估硫代葡萄糖苷含量。离子图谱分析被证明具有高度敏感性，硫代葡萄糖苷黑芥子硫苷酸钾的检测限可达万亿分之三。该方法利用了硫代葡萄糖苷阴离子的碎片化，在离子阱质谱仪中，这种碎片化会持续产生一个磺酸酯开环葡萄糖部分，质荷比为259。本文首次提出了这种碎片化的分子内转移机制。这种碎片化可作为植物提取物中硫代葡萄糖苷类代谢产物的通用标识符，在液相色谱-质谱联用（LCMSn）中可用于对单个硫代葡萄糖苷进行阳性鉴定和定量。这些方法为聚焦代谢组学分析和植物育种系筛选提供了灵敏的工具。
