Research has shown that aqueous and etheric coriander extracts, composed of phenolics and carotenoids, exhibit a considerable antioxidant action. Considering the importance of natural antioxidants in the reduction of free radicals and oxidised com-pounds, coriander extracts obtained through sequential extraction, were administered by gavage to Wistar rats during 30 and 60 d consecutively. At the end of each experimental period, the animals were sacrificed to obtain the blood and the liver. The effect of extracts on plasma and liver lipid peroxidation was assessed by evaluation of thiobarbituric reactive substances. Initially, the aqueous extract demonstrated a superior antioxidant activity in plasma but this was replaced by the etheric extract by the end of the experiment. Of the 2 extracts, in the etheric exerted a superior antioxidant activity in both liver and plasma. The effectiveness of the extracts appears to be related to the biological material that is used (liver or plasma), furthermore to the duration of administration and the type of extract.