Electron Donation Mechanisms of β‐Carotene as a Free Radical Scavenger

Abstract

ABSTRACT The free radical scavenging ability of β‐carotene was studied using free radical 2,2‐diphenyl‐1‐picryl‐hydrazyl (DPPH). As the concentration of β‐carotene in acetone increased, the absorbance of DPPH at 517 nm decreased, which indicates that β‐carotene scavenges free radicals. It was shown that β‐carotene does not work as an antioxidant in soybean oil. The NMR spectrum of DPPH with BHA in CDCl 3 showed a new peak at 5.0(d) was formed and the peak at 6.6(d) from BHA was split into 2 peaks, which may be due to the hydrogen atom donation from BHA to DPPH. The NMR spectra of DPPH with p‐carotene did not change during reaction and no peak was formed.