Evaluation of the antioxidant potentials of ten leafy vegetables extracts commonly consumed by the Ghanaian population
Electronic Journal of Environmental, Agricultural and Food Chemistry
Applied Radiation Biology centre, Reseach Scientist and Centre Manager Ghana Atomic Energy Commission, Ghana
Ten traditional leafy vegetables commonly consumed by Ghanaians have been evaluated for their antioxidant potential based on their polyphenolic and flavonoid contents. Among the plants studied the methanol extracts of Ocimum basilicum (akokobesa), and Amaranthus incurvatus (aleefo) exhibited the highest phenolic content of 16.4 mg GAE/g dw and 11.3mg dw GAE/g respectively. The highest phenolic content for water extracts were seen in Manihot esculenta (cassava; 9.29mg GAE/g dw) and Hibiscus sabdariffa (shuuré; 7.28mg GAE/g dw) and C esculanta (7.11 mg GAE/g dw). The methanol extracts of H. sabdariffa (Shuuré), Vernonia amygdalina (bitter leaves), Manihot esculenta (cassava leaves) and Ocimum basilicum (akokobesa) recorded the highest flavonoid content (FC) of 99.14 μg QE/g dw, 70.20μg QE/g dw, 70.08μg QE/g dw and 63.37μg QE/g dw respectively. For the FC of the aqueous extracts the order was; A. incurvatus > H. sabdariffa > Talinum triangulare> Colocasia esculenta > M. esculenta > V. amygdalina> O. basilicum > Solanum macrocarpon > Launaea taraxacifolia > Corchorus olitorius. A good positive correlation r 2= 0.663 was observed between polyphenolic content and antioxidant values for the aqueous extracts, however, no correlation was found between flavonoids, polyphenolics and total antioxidants. The study indicates that the leafy vegetables consumed by Ghanaians are potentially rich sources of dietary polyphenolic compounds and antioxidants, and might contribute important health and nutraceutical benefits to consumers.
Amaranthus; Amaranthus hybridus; Colocasia esculenta; Corchorus olitorius; Gymnanthemum amygdalinum; Hibiscus sabdariffa; Launaea; Manihot esculenta; Ocimum; Ocimum basilicum; Solanum; Solanum macrocarpon; Talinum triangulare; Vernonia amygdalina