Comparative Study of the Antioxidative Activity of Culinary Herbs and Spices, and Hepatoprotective Effects of Three Selected Lamiaceae Plants on Carbon Tetrachloride-Induced Oxidative Stress in Rats.

The purpose of this study was to compare the antioxidative activity of 68 culinary herbs and spices, and to evaluate the hepatoprotective effects of highly antioxidative plants (selected after an in vitro study) on carbon tetrachloride-induced oxidative stress in rats. Six Lamiaceae plants (oregano, common thyme, peppermint, lemon balm, sweet marjoram and rosemary) were found to be among the top 10 plants showing high total oxygen radical absorbance capacity (T-ORAC: sum of hydrophilic and lipophilic ORAC (H- and L-ORAC)). Their T-ORACs were composed of > 90% H-ORACs. Next, we prepared hydrophilic fractions of three selected Lamiaceae plants (peppermint, lemon balm and rosemary), in which bitterness and lipophilic odorants were reduced. Oral administration of these fractions in rats decreased aspartate aminotransferase and alanine aminotransferase activities in serum, inhibited lipid peroxidation, and restored superoxide dismutase and glutathione 5-transferase activities in carbon tetrachloride-treated rats. Antioxidants in plants could exert a hepatoprotective effect by scavenging free radicals. [ABSTRACT FROM AUTHOR]