Abstrait

The effect of drying temperature on the antioxidant activity of thyme extracts.

Faten H Thamer, Eqbal MA Dauqan, Khalid M Naji, Yahya M Alshaibi

This investigation is aimed at studying the influence of different drying temperatures on the
antioxidant activity for thyme leaves. In the present study different spectrophotometric methods
(DPPH, FRAP) are using to investigate the antioxidant activities of thyme plants. The results showed
that the drying temperature influences the antioxidant activity. The antioxidant activity of all studied
extracts decreased with increasing temperature attending decreasing in total phenol. Fresh thyme
shows the highest antioxidant activity (0.014 BHTE.mL-1, 0.0064 AAE and 0.0062 GAE).mL-1 extract
and total phenol content (8.78 10-4 mol GAE and 7.50 10-3 mol AAE).mL-1 of extract. Whereas thyme
dried at 40°C show the lowest antioxidant activity, (0.0042 BHTE, 0.0019 AAE and 0.0018 GAE).mL-1
of plant extract and total phenol contents (4.30 10-3 AAE and 4.68 10-4 GAE).mL-1 of plant extract.