Plant tissues are rich in a wide range of phenolic compounds, such as chalcones, tocopherols and hydroxilated flavonoids. Flavonoids have been reported to have multiple biological effects, including antioxidant ability. In some pathological situations O₂ is reduced in a univalent pathway to yield superoxide anion (O₂^.).This oxygenated free radical is implicated in cell damage either by a direct nucleophilic effect on membrane phospholipids, or by an indirect generation of hydroxyl radical (OH) which can induce lipoperoxidation processes. The peroxidation of unsaturated fatty acids in biological membranes by oxygen free radicals is thought to be a pathogenic mechanism in degenerative or other disease and processes like ageing, cancer and acute respiratory distress syndrome.

The purpose of this study is to examine level of lipid peroxidation (LP) (Orenchrona method) after chronic treatment of carbon tetrachloride, as well as possibility of modulation of intoxication with an antioxidant rosemary extract. Wistar rats (180-220 g weight, 6 per group) were used. The control group was given 0.9% NaCl (I) during 10 days (0.5ml/rat, i.p.). The second group (II) consist of animals treated with carbon tetrachloride (in i.p. dose 6ml/kg mg/kg). Rosemary extract (III) was given intraperitoneally in dose 20 mg/kg. The fourth group of animals treated with extract 5 days before the II treatment.

Our results show that the level of LP is increased in liver in group II in relation with animals of all other experimental groups. It is important that the level of LP is decreased in group III, IV in relation with intoxicated rats (II). Those results suggest that Rosemary extract might be used as protectors. In conclusion, the scavenge effects of this extract on active oxygen radicals were established. It could be of interest as a pharmaceutical source for remedies in the therapy of free-radical-dependent diseases.