Department of Chemistry, Wuhan University, Wuhan 430072, China.
J Agric Food Chem. 2022 Jul 20;70(28):8808-8818. doi: 10.1021/acs.jafc.2c02190. Epub 2022 Jul 7.
In this study, a screening strategy was established based on ultrahigh-performance liquid chromatography coupled with high-resolution mass spectrometry assisted by chemical isotope labeling (CIL-UPLC-HRMS) for screening and identifying abscisic acid (ABA) catabolites. Based on the structures of known ABA catabolites, this strategy first proposed the structures of catabolites to be discovered. Afterward, a pair of isotope reagents ,-2-dimethylaminoethylamine (DMED) and -DMED were used as labeling reagents to label the carboxyl groups in ABA and its catabolites. Then, the mass-to-charge ratio (/) of DMED- and -DMED-labeled ABA catabolites was calculated based on the labeling schema. In light of the characteristic fragmentation patterns of the DMED-labeled standards of ABA and its catabolites, screening criteria were formulated. Using our strategy, ABA, ABA, and 18 ABA catabolites were identified from seven plant samples. Of the identified catabolites, 16 were known, and to our knowledge, 2 were previously unidentified. Our findings contribute to ABA catabolic network improvement.
在本研究中，建立了一种基于超高效液相色谱与高分辨质谱联用结合化学同位素标记（CIL-UPLC-HRMS）的筛选策略，用于筛选和鉴定脱落酸（ABA）代谢产物。基于已知 ABA 代谢产物的结构，该策略首先提出了待发现代谢产物的结构。随后，使用一对同位素试剂 -2-二甲氨基乙胺（DMED）和 -DMED 作为标记试剂，标记 ABA 及其代谢产物中的羧基。然后，根据标记方案计算 DMED 和 -DMED 标记的 ABA 代谢产物的质荷比（m/z）。根据 DMED 标记的 ABA 及其代谢产物标准品的特征碎片模式，制定了筛选标准。使用我们的策略，从七个植物样品中鉴定出 ABA、ABA 和 18 种 ABA 代谢产物。在鉴定出的代谢产物中，有 16 种是已知的，据我们所知，有 2 种是以前未鉴定出的。我们的研究结果有助于完善 ABA 代谢网络。
