Evaluation of antioxidative properties of Allium species growing wild in Italy.

The genus Allium (Alliaceae) is an important dietary source of antioxidant phytochemical products. The antioxidant activity of some Allium species is well known but no information is available on the in vitro antioxidant activities of Italian Allium species growing wild. The aim of this study was to examine the in vitro antioxidant activity of aqueous extracts of different parts belonging to three Allium species growing wild, endemic to Italian flora: Allium neapolitanum Cyr., Allium subhirsutum L. and Allium roseum L., compared with the in vitro antioxidant activity of aqueous extracts of bulbs and leaves of the greatly studied garlic (Allium sativum L.). The antioxidant potential of extracts was evaluated using two different spectrophotometric assays: the DPPH test and FRAP assay. Furthermore the polyphenolic content was determined in all Allium species. The flowers of species growing wild showed the higher antioxidant power. Interesting results were shown even by the leaves, while the antioxidant capacity of the bulbs was lower. A correlation between the phenolic contents and the antioxidant activity was discovered. The differences in antioxidant capacity reflect the variability in the Allium species and the parts of the plant used and that the bulb of Allium sativum did not show higher antioxidant power.