A healthy and diversified eating is essential for the maintenance of physical and mental health, and despite the current trend that appreciates the convenience of eating, it is noted that the population is increasingly consuming fruit, both in natura and / or juices. However, the use of certain fresh fruits is accompanied by the consumption of the seeds, peels or other parts may contain antinutritional factors, molecules and / or compounds that may adversely affect the bioavailability and / or digestibility of nutrients, such as inhibitors of trypsin. Such inhibitors may impair the utilization of proteins in food, but recent studies have been published also demonstrating the beneficial effects of the same. This study aimed to evaluate the trypsin inhibitors in aqueous extracts of fruits: guava (Psidium guajava L) varieties Kumagai (white) and Paluma (red), yellow passion fruit (Passiflora edulis f.) and watermelon (Citrullus vulgaris Schrad). Tests were done in order to detect the presence of antitryptic activity and the dosage of soluble proteins. Trypsin inhibitory activity was detected in all extracts tested, as well as soluble proteins. Thus, inhibition can be explained by the presence of an inhibitor protein, because it was possible, in seed extracts, in SDS-PAGE, to visualize a wide range of protein bands. It is noteworthy that in the study, the protein bands that coincide with the molecular masses of the trypsin inhibitors did not appear in a majority, showing that seed extracts are likely to have protein inhibitor, however sparingly, justifying the low antitryptic activity (1, 36 to 15.15 IU / mg of dry weight), also shown by the extracts of the pulp. Therefore, having the recommended consumption of fruits including guava, passion fruit and watermelon in sight, possibly this inhibitory activity is more related to benefits than to hazards, regarding one's health. However, it is important to emphasize a careful consumption of large quantities of seeds present in these fruits.
Guava 'Kumagai'; 'Paluma' guava; Passiflora edulis f.; Citrullus vulgaris Schrad; enzyme inhibitor; protein
