Nutritional profiling and antioxidant capacity of traditional underutilized leafy vegetables

Abstract

While global attention focuses on a handful of commercial leafy vegetables, hundreds of traditional species with potentially superior nutritional profiles sit neglected in local food systems. This research evaluated the proximate composition, mineral content, vitamin levels, and antioxidant capacity of seven underutilized leafy vegetables collected from local markets and home gardens in Mashhad, Khorasan province, Iran, during 2022-2023. Fresh leaf samples were analyzed for protein, iron, calcium, vitamin C, β-carotene, total phenolics, flavonoids, and antioxidant activity by DPPH and FRAP assays. Moringa and drumstick leaves recorded the highest protein content (6.84 and 7.12 g/100g), iron (11.82 and 10.64 mg/100g), and total antioxidant capacity. Drumstick leaf had the highest vitamin C at 186.2 mg/100g, while moringa led in β-carotene (9.38 mg/100g) and total phenolics (47.2 mg GAE/g). A strong positive correlation was found between total phenolics and DPPH radical scavenging activity (r = 0.94). These findings confirm that traditional leafy vegetables offer nutritional value comparable to or exceeding that of commercially popular greens and deserve integration into dietary recommendations and food security strategies for the region.