Free radical scavenging activity of papaya juice.
Papaya juice is an efficient scavenger of highly reactive hydroxyl radicals (OH.) formed during 60Co irradiation of water. The OH. radicals were detected by the electron spin resonance (ESR) technique of spin trapping using DMPO (5,5-dimethyl-1-pyrroline-N-oxide) or by a colorimetric assay in which salicylate is converted into polyhydroxybenzoic acids. Papaya juice is also able to quench the ESR signal of a stable free radical (TEMPOL) and the ESR signal of the DMPO-OH adduct. The active substance(s) in papaya juice are heat-stable, dialyzable, and soluble in water but not in lipid solvents. The active agents do not appear to be ascorbate, tocopherol, or carotenoids.
Webman
E J
EJ
Department of Biochemistry and Biophysics, John A. Burns School of Medicine, University of Hawaii, Honolulu 96822.
Edlin
G
G
Mower
H F
HF
D003497:Cyclic N-Oxides; D005609:Free Radicals; D005638:Fruit / Q000528:radiation effects*; D006254:Hawaii; D006878:Hydroxides; D017665:Hydroxyl Radical; D010571:Pest Control / Q000379:methods; D013113:Spin Labels; D014867:Water / Q000528:radiation effects
D003497:Cyclic N-Oxides; D005609:Free Radicals; D006878:Hydroxides; D013113:Spin Labels; D014867:Water; D017665:Hydroxyl Radical; C001803:tempol