title: Flavonoids in tropical citrus species.
abstract: HPLC with PDA and MS(2) detection was used to identify and quantify flavonoids in the tropical citrus species  Citrus microcarpa ,  Citrus hystrix ,  Citrus medica  var. 1 and 2, and  Citrus suhuiensis . Most of these species contained high amounts of flavones, flavanones, and dihydrochalcone C- and/or O-glycosides, which were identified on the basis of HPLC retention times, cochromatography with available authentic standards, absorbance spectra, and mass spectral fragmentation patterns. Among the major compounds detected were apigenin-6,8-di-C-glucoside, apigenin-8-C-glucosyl-2″-O-rhamnoside, phloretin-3',5'-di-C-glucoside, diosmetin-7-O-rutinoside, hesperetin-7-O-neohesperidoside, and hesperetin-7-O-rutinoside. Most of the dihydrochalcone and flavone C-glycosides have not previously been detected in tropical citrus. C. microcarpa contained a high amount of phloretin-3',5'-di-C-glucoside. Most of the tropical citrus flavanones were neohesperidoside conjugates, which are responsible for imparting a bitter taste to the fruit. Only C. suhuiensis fruit contains rutinoside, a nonbitter conjugate.
authors: Plant Products and Human Nutrition Group, Graham Kerr Building, School of Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow G12 8QQ, United Kingdom.
authors: Suri
authors: S
authors: Roowi
authors: Alan
authors: A
authors: Crozier
mesh_terms: D002957:Citrus / Q000737:chemistry*; D005419:Flavonoids / Q000737:chemistry*; D005638:Fruit / Q000737:chemistry; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry*; D014329:Tropical Climate
chemical_list: D005419:Flavonoids; D010936:Plant Extracts