The present study sought to determine the antioxidant activity and protective ability of water-extractable phytochemicals from Salvia officinalis leaves (strongly aromatic leaves used in flavoring cooked foods) on lipid peroxidation induced by some pro-oxidants in rat brain and liver homogenates in vitro. Aqueous extracts of the leaves were prepared, and the ability of the extract to inhibit 25 microM FeSO(4)- and 7 microM sodium nitroprusside-induced lipid peroxidation in isolated rat brain and liver was determined. Subsequently, the ascorbic acid content, total phenol content, reducing power, Fe(II) chelating, and .OH radical scavenging ability of the extracts were determined as indices of antioxidant activity. The results of the study revealed that the extract inhibited malondialdehyde (MDA) production in basal and pro-oxidant-induced lipid peroxidation in the brain and liver in a dose-dependent manner. The percentage induction of lipid peroxidation by Fe(II) and sodium nitroprusside was higher in the brain than the liver; however, the level of inhibition of MDA production in the brain was significantly (P < .05) higher than the liver. The ascorbic acid (10.3 +/- 2.5 mg/g) and total phenol (7.6 +/- 1.2 mg/g) contents of the leaves were high; likewise, the aqueous extract had high reducing power and Fe(II) chelating ability but low .OH radical scavenging ability. This antioxidant and protective effect of this leaf could be harnessed in the management and prevention of degenerative diseases associated with oxidative stress.