title: Antioxidant activities and antitumor screening of extracts from cranberry fruit (Vaccinium macrocarpon).
abstract: Polyphenolic compounds in cranberries have been investigated to determine their role in protection against cardiovascular disease and some cancers. Extracts of whole fruit were assayed for radical-scavenging activity and tumor growth inhibition using seven tumor cell lines. Selective inhibition of K562 and HT-29 cells was observed from a methanolic extract in the range of 16-125 microg/mL. Radical-scavenging activity was greatest in an extract composed primarily of flavonol glycosides. Seven flavonol glycosides were isolated and purified from whole fruit for further evaluation; the anthocyanin cyanidin 3-galactoside was also purified for comparison with the flavonoids. Three flavonol monoglycosides were newly identified by (13)C NMR as myricetin 3-alpha-arabinofuranoside, quercetin 3-xyloside, and 3-methoxyquercetin 3-beta-galactoside (isorhamnetin); the other four isolated were the previously identified myricetin 3-beta-galactoside, quercetin 3-beta-galactoside, quercetin 3-alpha-arabinofuranoside, and quercetin 3-alpha-rhamnopyranoside. These compounds were evaluated for 1,1-diphenyl-2-picrylhydrazyl radical-scavenging activity and ability to inhibit low-density lipoprotein oxidation in vitro. Most of the flavonol glycosides showed antioxidant activity comparable or superior to that of vitamin E; cyanidin 3-galactoside showed activity superior to that of the flavonoids as well as vitamin E or Trolox in both antioxidant assays.
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000032:analysis / Q000494:pharmacology*; D000975:Antioxidants / Q000032:analysis / Q000494:pharmacology*; D004354:Drug Screening Assays, Antitumor; D005419:Flavonoids / Q000032:analysis / Q000737:chemistry / Q000494:pharmacology; D044948:Flavonols; D016166:Free Radical Scavengers / Q000494:pharmacology; D005638:Fruit / Q000737:chemistry*; D006027:Glycosides / Q000494:pharmacology; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology*; D014407:Tumor Cells, Cultured; D029799:Vaccinium macrocarpon / Q000737:chemistry*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D005419:Flavonoids; D044948:Flavonols; D016166:Free Radical Scavengers; D006027:Glycosides; D010936:Plant Extracts