In vitro enzyme activity and in vivo healing activity of the protein extract from pineapple peel

The pineapple is a fruit that has wide acceptance worldwide both in natural form, as industrialized. Your peel is a residue generated by food industries and from this residue can obtain a protein extract which is a good source of bromelain. This study aimed to obtain a protein extract from pineapple peel, evaluate its enzyme activity and its healing properties in skin lesions in rats. Seven animal groups were used: control, treated with 5% of protein extract, 10% of protein extract and pure protein extract; 5% of commercial bromelain, 10% of commercial bromelain and pure commercial bromelain. The animals were subjected to a tissue incision and treated for 21 days. Proteolytic and specific activities of the protein extract were 1.30 U mg-1 and 45 x 10-3 U μg-1 and, for commercial bromelain, 1.04 U mg-1 and 6 x 10-3 U μg-1, respectively. In the histology of the lesion, there was no significant difference between the control and treated groups; however, macroscopically, the prepared topical formulations assisted in the recovery of skin lesions, providing a significant reduction in their width, in the groups treated with pure protein extract, 5 and 10% commercial bromelain, and pure bromelain.

Mechanism of firmness loss in guava cv. Pedro Sato during ripening at room temperature

Abstract Guava (Psidium guajava L.) is fruit with very short shelf life due to associated with the loss of firmness in the pulp and information on the activity of enzymes that degrade pectic substances, as well as the amount of pectin, is very contradictory and not clearly defined. This work showed that the firmness of the fruit decreased sharply on the first four day­s of ripening. The identified phenolic compounds had their content increased with fruit maturation. The addition of the enzymes cellulase and hemicellulase in the pectin extraction in fruits of Psidium guajava revealed higher contents of this polyssacaride that the ones reported in literature, highlighting pectin as the responsible for the firmness of these fruits at more adequate contents. β-D-glucosidase was identified as one of the responsible enzymes for the maturation of P. guajava fruits. Thus, studies about possible inhibitory effects of this enzyme in P. guajava fruits may reveal an important tool to reduce pectin release and early maturation of these fruits.