High content of dopamine, a strong antioxidant, in Cavendish banana.

A strong water-soluble antioxidant was identified in the popular commercial banana Musa cavendishii. It is dopamine, one of the catecholamines. For suppressing the oxygen uptake of linoleic acid in an emulsion and scavenging a diphenylpicrylhydrazyl radical, dopamine had greater antioxidative potency than glutathione, food additives such as butylated hydroxyanisole and hydroxytoluene, flavone luteolin, flavonol quercetin, and catechin, and similar potency to the strongest antioxidants gallocatechin gallate and ascorbic acid. Banana contained dopamine at high levels in both the peel and pulp. Dopamine levels ranged from 80-560 mg per 100 g in peel and 2.5-10 mg in pulp, even in ripened bananas ready to eat. Banana is thus one of the antioxidative foods.