Functional potential of tropical fruits with respect to free bioactive amines

The profile and levels of 10 bioactive amines were determined in five tropical fruits, among them, pineapple, guava, papaya, mango and passion fruit. The amines were extracted from the Brazilian fruits with 1 N HCl and analyzed by ion-pair HPLC, post-column derivatization with o-phthalaldehyde and fluorimetric detection. Five amines were found in the fruits (spermidine, spermine, putrescine, serotonin and agmatine). Total amines levels varied from 0.77 mg/100 g in mango up to 7.53 mg/100 g in passion fruit. Spermidine was detected in every fruit whereas putrescine and spermine were found in most of them. Agmatine was detected in some samples of pineapple, papaya and passion fruit and serotonin was present in pineapple and passion fruit. Passion fruit is a good source of the polyamines spermidine and spermine (3.05 and 2.43 mg/100 g, respectively) and, therefore, could play an important role in growth, health, antioxidant activity and membrane permeability. Papaya is a good source of serotonin (0.99 mg/100 g), which has been associated with enabling the gut to mediate reflex activity and also with decreasing the risk of thrombosis. Histamine, a peripheral vasodilator, and the vasoconstrictors tyramine, tryptamine and phenylethylamine, as well as cadaverine were not detected in any of the fruits analyzed. Due to the diversity of amines in these fruits, they can provide different functional properties and, therefore, can be used for different nutritional needs.