Interaction of hydroxycinnamic acid derivatives with the Cl3COO radical: a pulse radiolysis study.
The electron transfer reactions between the trichloromethylperoxyl radical (Cl3COO*) and hydroxycinnamic acid derivatives, including chlorogenic acid, sinapic acid, caffeic acid, ferulic acid and 3,4-(methylenedioxy)cinnamic acid, have been studied by pulse radiolysis. The hydroxycinnamic acid derivatives, especially sinapic acid, are identified as good antioxidants for reduction of Cl3COO* via electron transfer reactions. From buildup kinetic analysis of phenoxyl radical, the rate constant for reaction of Cl3COO* with sinapic acid has been determined to be 8.2x10(7) dm3 mol(-1) s(-1), while the rate constants of electron transfer from other hydroxycinnamic acid derivatives to Cl3COO* were obtained to be about 2x10(7) dm3 mol(-1) s(-1). The reaction of 3,4-(methylenedioxy) cinnamic acid with Cl3COO* was investigated as an evidence for the electron transfer mechanism.
Pan
J X
JX
Laboratory of Radiation Chemistry, Shanghai Institute of Nuclear Research, Academia Sinica, PR China.
Wang
W F
WF
Lin
W Z
WZ
Lu
C Y
CY
Han
Z H
ZH
Yao
S D
SD
Lin
N Y
NY
D000975:Antioxidants / Q000737:chemistry; D003373:Coumaric Acids / Q000737:chemistry*; D004579:Electron Transport; D005609:Free Radicals / Q000737:chemistry; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry*; D066298:In Vitro Techniques; D007700:Kinetics; D011675:Pulse Radiolysis; D013053:Spectrophotometry
D000975:Antioxidants; D003373:Coumaric Acids; D005609:Free Radicals; D006843:Hydrocarbons, Chlorinated