Antioxidant and proximate properties of underutilized vegetables in western Nigeria
The discovery and utilisation of the wide range of medicinal plant resources is vital towards improved global health care delivery system. There is paucity of information of the antioxidant profile and nutritional properties of diverse indigenous vegetables in Nigeria. This study was conducted to evaluate the antioxidant and proximate composition of six indigenous underutilized vegetables of southwest Nigeria: Solanum americanum, Jatropha gossypifolia, Bidens pilosa, Launea taraxacifolia, Celosia trigyna and Cucurbita maxima. The vegetables were harvested, dried and their water extracts investigated for total antioxidants, phenolics, flavonoids, ferric reducing antioxidant power (FRAP), scavenging activities and proximate compositions using standard procedures. Data were analysed using ANOVA at α 0.05. Assessment of total phenolic content, total flavonoids, ferric acid antioxidant power, free radical scavenging activity and proximate compositions of the vegetables showed significant variations in their antioxidant potentials. Total phenolic content of the vegetables ranged from 173.33 to 993.33 mg 100 g-1. Bidens pilosa had the highest while Cucurbita maxima had the least, and all of these vegetables were relatively high in phenolic content. Flavonoid content ranged from 40 to 1262 mg 100 g-1 in the vegetables, the trend was Bidens pilosa > Jatropha gosssypifolia > Solanum americanum > Launea taraxacifolia > Cucurbita maxima > Celosia trigyna. Ferric reducing power was between 57.33 (J. gossypifoli) and 946.67 mg 100 g-1 (L. taraxacifolia). DPPH scavenging activity was between 43.33 and 52.69%. Total antioxidant activity was highest for B. pilosa (325.23 mg 100 g-1) while the least was for C. trigyna (88.74 mg 100 g-1). Moisture contents of dried vegetables ranged from 9.8-12.93%, ash from 9.71-10.71 g 100 g-1 and protein contents were high at 19.70-32.60 g 100 g-1. Fat contents were low at 0.98-3.56% while crude fibre ranged from 8.46 (J. gossipyfolia) to 13.56 (L. taraxacifolia). The vegetables are good sources of antioxidants, protein and crude fibre and their consumption may enhance overall body health.
Oduntan, A.O., Fasoyiro, S.B., Akinfasoye, J.A., Adeboyejo, F.O. and Akintoye, H.A. (2018). Antioxidant and proximate properties of underutilized vegetables in western Nigeria. Acta Hortic. 1225, 255-260
antioxidant supplement, indigenous leafy vegetable, nutraceuticals, underutilised