title: Identification and Characterization of Kukoamine Metabolites by Multiple Ion Monitoring Triggered Enhanced Product Ion Scan Method with a Triple-Quadruple Linear Ion Trap Mass Spectrometer.
abstract: Kukoamines are a series of bioactive phytochemicals conjugated by a polyamine backbone and phenolic moieties. Understanding the structural diversity of kukoamine metabolites in plants is meaningful for drug discovery. In this study, an LC-MS/MS method was established for kukoamine profiling and characterization from lycii cortex (LyC) via a triple-quadrupole linear ion trap mass spectrometry (Q-TRAP). On the basis of the typical fragmentation of kukoamine, a diagnostic ion, which represents the features of the backbone and phenolic substitute, was chosen as the product ion for precursor ion scan, and then the screened precursor ions were applied to a successive multiple ion monitoring triggered enhanced product ion scan (MIM-EPI) to simultaneously present the profile survey and MS/MS acquisition. Because the MIM narrowed the ion scan range in Q1 and the ion trap enhanced the ion fragments passing through Q2, the qualitative capability of quadrupole MS can be greatly improved, especially for capture of the uncommon metabolites. There are 12 kukoamine metabolites identified from LyC, with either spermine or spermidine backbone and with conjugation of one to three dihydrocaffeoyls or other kinds of phenolic moieties. Except for kukoamines A and B, other metabolites were identified in LyC for the first time. This approach can be utilized for metabolite identification in other substrates.
authors.affiliation: Research Group for Bioactive Products, Department of Biomedical Sciences, City University of Hong Kong , 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Li
authors.affiliation: Research Group for Bioactive Products, Department of Biomedical Sciences, City University of Hong Kong , 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Haixing
authors.initials: H
authors.lastname: Wang
authors.affiliation: Research Group for Bioactive Products, Department of Biomedical Sciences, City University of Hong Kong , 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Chunyan
authors.initials: C
authors.lastname: Zhao
authors.affiliation: Research Group for Bioactive Products, Department of Biomedical Sciences, City University of Hong Kong , 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Ye-Qing
authors.initials: YQ
authors.lastname: Huang
authors.affiliation: Research Group for Bioactive Products, Department of Biomedical Sciences, City University of Hong Kong , 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Xiaowei
authors.initials: X
authors.lastname: Tang
authors.affiliation: Research Group for Bioactive Products, Department of Biomedical Sciences, City University of Hong Kong , 83 Tat Chee Avenue, Hong Kong SAR, China.
authors.forename: Hon-Yeung
authors.initials: HY
authors.lastname: Cheung
mesh_terms: D002851:Chromatography, High Pressure Liquid; D004365:Drugs, Chinese Herbal / Q000737:chemistry; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D011073:Polyamines / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism*; D013095:Spermidine / Q000737:chemistry; D013096:Spermine / Q000737:chemistry
chemical_list: D004365:Drugs, Chinese Herbal; C000599698:Lycii Radicis Cortex; D011073:Polyamines; D013096:Spermine; D013095:Spermidine
keywords: MIM-EPI; Q-TRAP; fragmentation behavior; kukoamines; molecular diversity; structural characterization