Nutritional and Functional Characterisation of Edible Leaves and Flowers from Selected Traditional Plants in Mozambique

Hidden hunger remains an important nutritional challenge in sub-Saharan Africa, where diets are frequently based on staple foods with limited micronutrient diversity. Traditional food plants represent valuable resources for improving dietary quality; however, several commonly consumed fractions remain insufficiently characterised. This study evaluated the nutritional composition and biological properties of four traditional or locally available food plants from Mozambique: Corchorus olitorius, Manihot esculenta, Moringa oleifera and Portulaca oleracea. Proximate composition, mineral, fatty acids, tocopherols, soluble sugars, organic acids, and total phenolic contents were determined using standard methods. Antioxidant, antibacterial, and cytotoxic activities were also assessed in vitro tests. The results showed clear differences among species and plant fractions. M. esculenta leaves presented the highest protein content (28.99 ± 0.01 g/100 g dw), total phenolic content (15.3 ± 0.3 mg GAE/g dw), and antioxidant activity, with TEAC values of 172.6 ± 10.1 μmol TE/g dw and 128.65 ± 8.38 μmol TE/g dw for ABTS and FRAP tests, respectively. M. oleifera leaves were notable for their calcium and α-tocopherol contents, reaching 3150.1 ± 145.5 mg/100 g dw and 3727 ± 19 μg/100 g dw, respectively. C. olitorius leaves had the highest iron content, 18.3 ± 0.6 mg/100 g dw, and showed antibacterial activity against Yersinia enterocolitica with a MIC of 0.31 mg/mL. Regarding other plant parts, M. oleifera flowers exhibited considerable phenolic content and antioxidant activity, suggesting potential for valorisation. Most extracts showed low cytotoxicity, although C. olitorius leaves presented moderate antiproliferative activity against MCF-7 cells. These results support the value of traditional Mozambican food plants for dietary diversification and future food or nutraceutical applications.