Geo-spatial variation of nutritional and phytochemical content of Okra in major agro-commercial zones in Ilorin, Nigeria

Abstract

This study evaluated the proximate and phytochemical composition of Abelmoschus esculentus samples from three major markets in Ilorin: Oja-Oba, Mandate, and Ganmo to assess nutritional quality, bioactive potential, and spatial variability. Samples were analyzed for moisture, total dry matter, ash, crude protein, fat, crude fibre, and carbohydrates using standard analytical methods, while phytochemical profiling quantified alkaloids, saponins, flavonoids, tannins, phenolics, terpenoids, glycosides, steroids, and cardiac glycosides. Moisture content ranged from 66.71 ± 3.22% to 68.60 ± 2.15%, total dry matter from 31.54 ± 0.85% to 33.30 ± 2.35%, ash from 3.85% to 4.05%, and crude protein from 11.91 ± 1.80% to 12.51 ± 1.34%, indicating consistent nutritional contributions across markets. Fat and crude fibre were low (2.09–2.64% and 1.40–1.92%, respectively), while carbohydrates were slightly higher in Mandate samples (12.79 ± 0.66%). Phytochemicals were abundant, with alkaloids (16.52–20.07 mg/100 g) and saponins (15.53–19.27 mg/100 g) dominant, flavonoids (6.02–7.32 mg/100 g) and tannins (1.78–3.49 mg/100 g) moderate, and phenolics stable across markets (3.17–3.21 mg/100 g). Terpenoids, glycosides, steroids, and cardiac glycosides occurred at low but comparable levels. Limited spatial variability suggests compositional stability and reinforces the nutritional adequacy and functional potential of okra. These findings support targeted sourcing based on market origin for dietary and functional applications and provide a reference for future studies linking phytochemical profiles with agronomic and soil factors.