Effect of chlorogenic acid on hydroxyl radical.
Zang LY; Cosma G; Gardner H; Castranova V; Vallyathan V
Mol Cell Biochem 2003 May; 247(1-2):205-210
Chlorogenic acid (CGA) is considered to act as an antioxidant. However, the inhibitory effects of CGA on specific radical species are not well understood. Electron spin resonance (ESR) in combination with spin trapping techniques was utilized to detect free radicals. 5,5-Dimethyl-1-pyrroline-N-oxide (DMPO) was used as a spin trapping reagent while the Fenton reaction was used as a source of hydroxyl radical (*OH). We found that CGA scavenges *OH in a dose-dependent manner. The kinetic parameters, IC50 and Vmax, for CGA scavenging of *OH were 110 and 1.27 microM/sec, respectively. The rate constant for the scavenging of *OH by CGA was 7.73 x 10(9) M(-1) sec(-1). Our studies suggest that the antioxidant properties of CGA may involve a direct scavenging effect of CGA on *OH.
Antioxidants; Free-radicals; In-vitro-studies; In-vivo-studies; Hydroxyl-groups;
Author Keywords: chlorogenic acid; hydroxyl radical; ESR; spin trapping
Exposure Assessment Branch and Pathology and Physiology Research Branch, Health Effects Laboratory Division, National Institute for Occupational Safety and Health, Morgantown, WV 26505-2888, USA
Work Environment and Workforce: Mixed Exposures
Molecular and Cellular Biochemistry