Evaluation of in vitro antioxidant activity of aqueous extracts of some Italian spontaneous Allium species

The aim of this study was to examine the in vitro antioxidant activity of aqueous extracts of bulbs, leaves and flowers of three Allium spontaneous species which are endemic to the Italian flora (Pignatti, 1982): Allium neapolitanum Cyr., Allium subhirsutum L., Allium roseum L., and to compare them with the in vitro antioxidant activity of aqueous extracts of bulbs and leaves of the much studied garlic (Allium sativum L.). The antioxidant potential of aqueous extracts of all the species described above was evaluated using two different spectrophotometric assays: the 2,2-diphenylpicrylhydrazyl (DPPH°) test and the ferric reducing/antioxidant power (FRAP) assay.Good results were shown even by the leaves, while the antioxidant capacity of the bulbs was lower. The differences of antioxidant capacity underlined by this study reflect the variability bound to Allium species and the parts of the plant used. The bulbs of Allium sativum which represent the part largely consumed and abundantly studied do not show evidence of a higher antioxidant power.