Antioxidant Properties and Functional Food Potential of Selected Nigerian Indigenous Leafy Vegetables

Indigenous leafy vegetables constitute a critical component of dietary nutrition for millions of Nigerians, particularly in rural communities where access to diverse food sources is constrained. However, systematic scientific data on the antioxidant properties and functional food potential of Nigerian indigenous leafy vegetables remain fragmented, limiting their potential to be positioned in nutraceutical and health food markets. This study investigates the antioxidant content, phenolic profile, and functional food potential of six indigenous leafy vegetables, namely Vernonia amygdalina, Gnetum africanum, Celosia argentea, Corchorus olitorius, Talinum triangulare, and Amaranthus hybridus, sampled from markets in Lagos, Enugu, Port Harcourt, and Kano. Samples were analyzed for total phenolic content, flavonoid concentration, DPPH radical scavenging activity, FRAP antioxidant capacity, and proximate composition. Principle component analysis was applied to assess compositional relationships across species. Results indicate that Gnetum africanum exhibited the highest total phenolic content and DPPH scavenging activity, while Vernonia amygdalina showed the strongest correlation between bitterness compounds and anti-inflammatory potential. The study concludes that Nigerian indigenous leafy vegetables possess significant functional food properties that justify their promotion in public health nutrition strategies and commercial product development. Keywords: antioxidant, indigenous vegetables, functional food, phenolic content, Nigeria