Inhibitory effect of boldine on fish oil oxidation

The antioxidative effect of boldine, an alkaloid extracted from Peumus boldus Mol. (boldo), was assayed on the spontaneous and on the metal‐induced oxidation of fish oil. The inhibitory effect of boldine was compared to those of dl‐α tocopherol, the flavonoid quercetin and the synthetic antioxidants butylated hydroxytoluene and butylated hydroxyanisole. Boldine, in all assays, showed a good antioxidative effect, which was comparable to that of quercetin and even better than that of dl‐α tocopherol and the synthetic antioxidants. Additive effects were observed when mixtures of boldine and quercetin or dl‐α tocopherol were assayed. The present study supports the potential use of boldine as a novel natural antioxidant for fish oil.