Proximate Composition, Bioactive Compounds and Total Antioxidant Capacity of Immature Leaves of Selected Fruit and Vegetable Crops

Abstract

The present study was undertaken to quantify the total phenolic content (TPC), total flavonoid content (TFC), total antioxidant capacity (TAC), proximate composition and chlorophyll content of immature leaves of seven selected crops namely Manihot esculenta (cassava), Ipomoea batatas (sweet potato), Cucurbita maxima (pumpkin), Psophocarpus tetragonolobus (winged bean), Lagenaria siceraria (bottle gourd), Spondias dulcis (ambarella) and Passiflora edulis (passion fruit). TPC, TFC and TAC were determined using folin-ciocalteu method, colorimetric method and ferric iron reducing antioxidant power (FRAP) respectively. The moisture, ash and protein were analyzed using the methods reported by the Association of Official Analytical Communities (AOAC). The highest TPC (19.04 ± 0.76 mg GAE /g DW) and TAC (115.94 ± 6.27 mg TE / g DW) were recorded in Manihot esculenta leaves. Significantly, the highest TFC (134.02 ± 3.25 mg RE /g DW) and ash content (10.81 ± 0.21 %) were recorded in Ipomoea batatas leaves. The leaves of Psophocarpus tetragonolobus had the highest protein content (36.71 ± 0.10 %) and total chlorophyll content (2.60 ± 0.01 mg / g FW). According to the results, it can be concluded that all tested immature leaves contained marked amounts of bioactive compounds and total antioxidant capacity.