title: Identifying citrus limonoid aglycones by HPLC-EI/MS and HPLC-APCI/MS techniques.
abstract: HPLC coupled with normal phase electron ionisation (EI) and atmospheric pressure chemical ionisation (APCI)/ mass spectrometry methods has been applied to identify 17 known neutral limonoid aglycones from Citrus sources. The HPLC-MS data from the known limonoids provided chromatographic characteristics, APCI-derived molecular weight data and EI fragmentation data for each limonoid. EI fragmentation patterns for the limonoids were correlated with structural characteristics. The EI fragmentation patterns coupled with APCI-derived molecular weights were utilised as a potential method by which to discern the structural character of unknown citrus limonoids.
authors.affiliation: United States Department of Agriculture, Agricultural Research Service, Western Regional Research Center, 800 Buchanan St. Albany, CA 94710, USA. gmann@pw.usda.gov
authors.forename: Gary D
authors.initials: GD
authors.lastname: Manners
authors.forename: Andrew P
authors.initials: AP
authors.lastname: Breksa
mesh_terms: D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002957:Citrus / Q000737:chemistry*; D036701:Limonins / Q000032:analysis / Q000737:chemistry*; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure
chemical_list: D036701:Limonins