Chemical ingredients and antioxidant activities of underutilized wild fruits

Abstract

This study evaluated nutritional values, bioactive constituents and antioxidant activities of the five wild underutilized fruits in the mountains of southwest Saudi Arabia (Coccinia grandis (L.) Voigt, Diospyros mespiliformis Hochst. Ex A.Dc., Cissus rotundifolius (L.), Ephedra foeminea Forssk., and Grewia villosa Willd.). The moisture content, crude fibers, total protein, total lipids, total hydrolyzable carbohydrate, total soluble sugars, and total free amino acids were analyzed. The results showed varying amounts among fruits of the five study species. In addition, the mineral composition, amino acid content, phenolic compounds, vitamins, and antioxidant activity were assessed. The highest content of total phenolic and total tannins was measured in D. mespiliformis (20.69 mg/g and 3.84 mg/g) and the lowest in E. foeminea (10.83 mg/g and 1.44 mg/g), respectively. The methanol extract (1 mg/ml) of D. mespiliformis displayed higher percentage of DPPH radical scavenging activity (87.36%). The methanol extract (1 mg/ml) of C. grandis exhibited the highest effect of total antioxidant activity and hydrogen peroxide scavenging activity (71.53%). The sufficient nutritional and antioxidant value of these wild fruits provide healthy food source for the local residents, much the same as many cultivated fruits and vegetables.