title: Degradation products of cyanidin glycosides from tart cherries and their bioactivities.
abstract: The bioactive anthocyanins present in tart cherries, Prunus cerasus L. (Rosaceae) cv. Balaton, are cyanidin 3-glucosylrutinoside (1), cyanidin 3-rutinoside (2), and cyanidin 3-glucoside (3). Cyanidin (4) is the major anthocyanidin in tart cherries. In our continued evaluation of the in vivo and in vitro efficacy of these anthocyanins to prevent inflammation and colon cancer, we have added these compounds to McCoy's 5A medium in an effort to identify their degradation products during in vitro cell culture studies. This resulted in the isolation and characterization of protocatechuic acid (5), the predominant degradation product. In addition, 2,4-dihydroxybenzoic acid (6) and 2,4,6-trihydroxybenzoic acid (7) were identified as degradation products. However, these degradation products were not quantified. Compounds 5-7 were also identified as degradation products when anthocyanins were subjected to varying pH and thermal conditions. In cyclooxygenase (COX)-I and -II enzyme inhibitory assays, compounds 5-7 did not show significant activities when compared to the NSAIDs Naproxen, Celebrex, and Vioxx, or Ibuprofen, at 50 microM concentrations. However, at a test concentration of 50 microM, the antioxidant activity of protocatechuic acid (5) was comparable to those of the commercial antioxidants tert-butylhydroquinone (TBHQ), butylated hydroxytoluene (BHT), and butylated hydroxyanisole (BHA), and superior to that of vitamin E at 10 microM concentrations.
authors.affiliation: Bioactive Natural Products and Phytoceuticals, Department of Horticulture and National Food Safety and Toxicology Center, Michigan State University, East Lansing, Michigan 48824, USA. nairm@msu.edu
authors.forename: N P
authors.initials: NP
authors.lastname: Seeram
authors.forename: L D
authors.initials: LD
authors.lastname: Bourquin
authors.forename: M G
authors.initials: MG
authors.lastname: Nair
mesh_terms: D000872:Anthocyanins / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism / Q000494:pharmacology; D000975:Antioxidants / Q000494:pharmacology; D001578:Benzopyrans / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D002478:Cells, Cultured; D002851:Chromatography, High Pressure Liquid; D003110:Colonic Neoplasms / Q000517:prevention & control; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D006801:Humans; D062385:Hydroxybenzoates / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D007249:Inflammation / Q000517:prevention & control; D007527:Isoenzymes / Q000037:antagonists & inhibitors; D009682:Magnetic Resonance Spectroscopy; D008565:Membrane Proteins; D011451:Prostaglandin-Endoperoxide Synthases; D027861:Prunus / Q000737:chemistry* / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D000872:Anthocyanins; D000975:Antioxidants; D001578:Benzopyrans; D052246:Cyclooxygenase 2 Inhibitors; D016861:Cyclooxygenase Inhibitors; D062385:Hydroxybenzoates; D007527:Isoenzymes; D008565:Membrane Proteins; C009091:protocatechuic acid; C017154:cyanidin; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; C496511:PTGS1 protein, human; C496540:PTGS2 protein, human; D011451:Prostaglandin-Endoperoxide Synthases; C428983:cyanidin 3-rutinoside