Suppressive effects of edible Thai plants on superoxide and nitric oxide generation

Suratwadee Jiwajinda, Vilai Santisopasri, Akira Murakami, Oe Kyung Kim, Ha Won Kim, Hajime Ohigashi

Research output: Contribution to journalArticlepeer-review

17 Scopus citations


We screened ethanol extracts from a total of 134 species of edible Thai plants for their suppressive effects on superoxide (O2-) generation using a xanthine (XA)-xanthine oxidase (XOD) assay system. When the extracts were tested at a concentration of 500 μg/ml, 28.4% significantly suppressed O2- generation. Of these active extracts, it was found that in 17.9% of cases the action was due to XOD inhibition, in 1.5% due to O2- scavenging activity, and in 9% due to both XOD inhibition and O2- scavenging. In addition, some plant extracts (25 species) which had been known to possibly possess anti-tumor promoting activity were tested for O2- and NO generation in cellular systems. In this test, 13 species exhibited strong inhibitory activity toward both O2- and NO generation. From the fruit pods of Oroxylum indicum (Bignoniaceae), a traditional vegetable in Thailand, two flavones, oroxylin A and chrysin, and a triterpene carboxylic acid, ursolic acid (UA), were identified as inhibitors of O2- generation in XA/XOD system. These compounds also showed marked inhibitory effects on the tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced O2- generation in dimethylsulfoxide (DMSO)-differentiated HL-60 cells. Our results suggest that, as we have reported earlier, edible Thai plants are promising sources of antioxidants with chemopreventive potential.

Original languageEnglish (US)
Pages (from-to)215-223
Number of pages9
JournalAsian Pacific Journal of Cancer Prevention
Issue number3
StatePublished - 2002
Externally publishedYes


  • Anti-oxidation
  • Chrysin
  • Oroxylin A
  • Oroxylum indicum
  • Thai plants
  • Ursolic acid

ASJC Scopus subject areas

  • Epidemiology
  • Oncology
  • Public Health, Environmental and Occupational Health
  • Cancer Research


Dive into the research topics of 'Suppressive effects of edible Thai plants on superoxide and nitric oxide generation'. Together they form a unique fingerprint.

Cite this