Phytochemical Screening, Extraction of Essential Oils and Antioxidant Activity of Five Species of Unconventional Vegetables

摘要

Unconventional vegetables, in general, are plants that have been largely consumed by the population at some point and, because of changes in eating behavior, now present reduced economic and social expression and have lost ground to other vegetables. The objectives of this study were to perform phytochemical screening of the ethanol extracts of Rumex acetosa L., Tropaeolum majus L., Solanum muricatum, Stachys byzantina K. Koch and Solanum betaceum Cav. and evaluate their antioxidant potentials via the methods involving scavaging of the DPPH free radical and the ABTS radical, phosphomolybdenum and reducing power. In phytochemical screening, five species of unconventional vegetables tested positive for tannins;for sesquiterpene, lactones and other lactones. These tests were positive for Tropaeolum majus L. and Rumex acetosa L., Solanum betaceum Cav. and Solanum muricatum tested negative for steroids. Only Solanum betaceum Cav. gave positive tests for flavonoids. Among the five plant species studied, Stachys byzantina K. Koch presented the greatest antioxidant potential in all the methods evaluated.