The results of the determination of the antioxidant activity are presented in Table 5.
The A. campestris extracts were more active than those of T. hirs- uta. For both species, the alcohol/water extract exhibited higher activity than the infusion except for A. campestris infusion which revealed a strong activity when determined by DPPH and b-caro- tene methods. Nevertheless, it must be noted that the strong activ- ity of the infusion as determined by b-carotene method could be attributed to the amount of the extract used compared to the other extracts (9.6 times higher). In addition, it should be noted that the infusion of T. hirsuta presented a very weak or negligible activity. Concerning the essential oil of A. campestris, it showed a feeble activity compared to alcohol/water extract and infusion However, it should be distinguished that the antioxidant activity of the ex- tracts is relatively weak compared to that of the standards. These findings, especially for essential oil, were comparable to these re- ported by Akrout et al. (2010).