Phytochemical characterization and bioactivities of different fruit parts of Tunisian barbary fig (Opuntia ficus-indica)

Abstract

The valorization of bio-waste to acquire products with high added value presents a great profit for the pharmaceutical, medicinal and food industries. Thus, seeds, peels, and pulps obtained from green (GFI), orange (OFI), and purple (PFI) Tunisian pear fruit (Opuntia ficus-indica L.) were evaluated in terms of phytochemical composition and biological activities. The peel part of the purple fruit contained the highest content of K, Ca, and Mg. While the seed possessed the highest P and Fe amounts. Moreover, the total carbohydrate contents in the different pear fruit parts ranged from 43.41% in the seeds (GFI) to 68.12% in pulp parts (OFI) and were significantly different from each other. The pulp parts showed much higher xylose and fructose contents, averaging 3.38 and 119.17 g/L. The seeds of the three varieties were characterized by higher levels of polyunsaturated fatty acids and mostly predominated by oleic acid that varied from 43.51 to 47.84% for the green and orange colored fruit seeds, followed by linoleic acid (32.76—37.1%). The seeds and peels parts contained higher levels of phenolic compounds with a total of 37 compounds compared to pulp extracts. The seeds of the three studied fruits possessed high repellency potentials against the red flour beetle (Tribolium castaneum). The greatest repellency activities were recorded in the purple (53.33%) and the orange (46.66%) fruit seeds at the concentration of 5 μL/cm2 and after 1h of exposure. The fruit parts showed considerable antibacterial and antifungal effects against Erwinia amylovora and Botrytis cinerea. The prickly pear fruit could be used as natural ingredients with potential biological activities.