Alkylperoxyl radical-scavenging activity of various flavonoids and other phenolic compounds: Implications for the anti-tumor-promoter effect of vegetables

Tomohiro Sawa, Mayumi Nakao, Takaaki Akaike, Kanji Ono, Hiroshi Maeda

Research output: Contribution to journalArticle

281 Citations (Scopus)

Abstract

We recently reported that alkylperoxyl radical (ROO·) enhanced carcinogenesis in rats treated with carcinogen (Sawa et al. Cancer Epidemiol. Biomarkers Prev. 1998, 7, 1007-1012), and the tumor promoting action of ROO· could be reduced by addition of hot-water extracts of vegetables (Maeda et al. Jpn. J. Cancer Res. 1992, 83, 923-928). Here we described the ROO·- scavenging activity of flavonoids and nonflavonoid phenolics and their role in anti-tumor-promoter effects. A model molecular species, ROO·, was generated from tert-butyl hydroperoxide (t-BuOOH) and heme iron, and the scavenging of t-BuOO· was determined by (a) bioassay based on the bactericidal action of ROO·, (b) luminol-enhanced chemiluminescence, and (c) electron spin resonance. Of 17 authentic plant phenolics tested, 9 compounds (including rutin, chlorogenic acid, vanillin, vanillic acid, neohesperidin, gallic acid, shikimic acid, rhamnetin, and kaempferol) showed remarkably high ROO·-scavenging activity. Some of them were detected and quantified in hot- water extracts of mung bean sprouts, used as the model vegetable, and their contents increased after germination, which paralleled very well to the ROO·-scavenging capacity of the vegetable extracts. Thus, a diet rich in these radical scavengers would reduce the cancer-promoting action of ROO·. Consequently, the carcinogenic potentials of oxygen-related radicals may be suppressed.

Original languageEnglish
Pages (from-to)397-402
Number of pages6
JournalJournal of Agricultural and Food Chemistry
Volume47
Issue number2
DOIs
Publication statusPublished - 1999 Feb 1
Externally publishedYes

Keywords

  • Alkylperoxyl radical
  • Anti-tumor- promoter
  • Flavonoids
  • Phenolic compounds
  • Radical scavenger

ASJC Scopus subject areas

  • Chemistry(all)
  • Agricultural and Biological Sciences(all)

Fingerprint Dive into the research topics of 'Alkylperoxyl radical-scavenging activity of various flavonoids and other phenolic compounds: Implications for the anti-tumor-promoter effect of vegetables'. Together they form a unique fingerprint.

  • Cite this