title: Trapping effect of eugenol on hydroxyl radicals induced by L-DOPA in vitro.
abstract: Many researchers have stated that eugenol might inhibit lipid peroxidation at the stage of initiation, propagation, or both, and many attempts have been made to elucidate the mechanism of its antioxidant activity. Nevertheless, details of its mechanism are still obscure. This study was carried out to investigate the trapping effect of eugenol on hydroxyl radical generated from L-3,4-dihydroxyphenylalanine (DOPA) in MiliQ water and the generation mechanism of the hydroxyl radical by this system which uses no metallic factor. This was studied by adding L-DOPA and 5,5-dimethyl-1-pyrroline N-oxide (DMPO) to phosphate buffered saline (PBS) or MiliQ water, and the generation of hydroxyl radical was detected on an ESR spectrum. By this method, the effect of antioxidants was detected as a modification of ESR spectra. We found that the eugenol trapped hydroxyl radicals directly, because it had no iron chelating action, did not trap L-DOPA semiquinone radical and inhibited hydroxyl radicals with or without iron ion.
authors.affiliation: Aomori University; 2-3-1 Kohbata, Aomori, Aomori 030-0943, Japan. ogata-ms@aomori-u.ac.jp
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ogata
authors.forename: Daisuke
authors.initials: D
authors.lastname: Kaneya
authors.forename: Kazuo
authors.initials: K
authors.lastname: Shin-Ya
authors.forename: Linxang
authors.initials: L
authors.lastname: Li
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Abe
authors.forename: Hironobu
authors.initials: H
authors.lastname: Katoh
authors.forename: Sachiko
authors.initials: S
authors.lastname: Seki
authors.forename: Yasuhide
authors.initials: Y
authors.lastname: Seki
authors.forename: Ryoko
authors.initials: R
authors.lastname: Gonda
authors.forename: Shiro
authors.initials: S
authors.lastname: Urano
authors.forename: Toyoshige
authors.initials: T
authors.lastname: Endo
mesh_terms: D000814:Aniline Compounds / Q000737:chemistry; D000978:Antiparkinson Agents / Q000737:chemistry*; D002614:Chelating Agents / Q000737:chemistry; D004578:Electron Spin Resonance Spectroscopy; D005054:Eugenol / Q000737:chemistry*; D017665:Hydroxyl Radical / Q000737:chemistry*; D007502:Iron Chelating Agents / Q000737:chemistry; D007980:Levodopa / Q000737:chemistry*; D016877:Oxidants / Q000737:chemistry*; D011748:Pyrogallol / Q000737:chemistry
chemical_list: D000814:Aniline Compounds; D000978:Antiparkinson Agents; D002614:Chelating Agents; D007502:Iron Chelating Agents; D016877:Oxidants; D011748:Pyrogallol; D017665:Hydroxyl Radical; D005054:Eugenol; D007980:Levodopa; C050795:N,N-dimethyl-4-anisidine