Opuntia ficus indica (L.) Mill. An Ancient Plant Source of Nutraceuticals

Opuntia ficus-indica (L.) Mill. (OFI) is a plant with numerous beneficial properties known in traditional medicine. It has been a domesticated plant in Latin America, Africa, Mediterranean countries, the Middle East, India and Australia. Nowadays, the research concentrates on natural compounds to lower costs and the possible side effects of synthetic compounds. The use of nutraceuticals, bioactive compounds of vegetable origin with important nutritional values, is encouraged. OFI has shown numerous activities due to its high content of antioxidants, including flavonoids and ascorbate, pigments, carotenoids and betalains, phenolic acids and other phytochemical components, such as biopeptides and soluble fibers. The most important effects of OFI are represented by the activity against acne, arthrosis, dermatosis, diabetes, diarrhea, fever, high blood pressure, prostatitis, rheumatism, stomachache, tumor, wart, allergy, wound, colitis and some viral diseases. Moreover, a promising role has been suggested in inflammatory bowel disease, colitis and metabolic syndrome. The most recent studies addressed the role of OFI in preventing and treating COVID-19 disease. In light of the above, this review summarizes the biological activities and health benefits that this plant may exert.