Isolation, identification, and structure of a potent alkyl-peroxyl radical scavenger in crude canola oil, canolol

Alkylhydroperoxides in oxidized oil are undesirable components because they become alkylperoxyl radicals (ROO center dot) in the presence of heme, hemoglobin, or myoglobin in red meat. ROO center dot are biochemically reactive and damage nucleic acids and proteins, thereby harming living cells. We isolated a component, a highly potent ROO center dot scavenger, from crude canola oil (rapeseed), which we designated canolol, and identified its chemical structure, 4-vinyl-2,6-dimethoxyphenol. The canolol content of crude canola oil greatly increased after the seed was roasted as compared with that from unroasted seed, but it decreased in highly purified oil. This anti-ROO center dot activity was highest in crude oil, deceased after each refining step, and was lowest in highly purified refined oil. Canolol was thus generated during roasting. As shown previously, canolol is one of the most potent anti-ROO center dot components in crude canola oil and its potency is much greater than that of well-known antioxidants, including a-tocopherol, vitamin C, beta-carotene, rutin, and quercetin.