| Essential oils have been studied for their unique ability to act as antioxidants. There is a large pool of publications describing the antioxidant activity of essential oils, however they all present results of research that was performed on a small number of oils and at most an individual botanical family or related species Antioxidant activities of 423 essential oils of 48 different botanical families were evaluated for their antioxidant activities as free radical scavenging agents using the 1,1-diphenyl-2-picryihydrazyl method. The EC50 of the 84 most active oils ranged from 4 to 2000 microg/mL. Oils having an EC50 of less than 300 mug/mL, (20 selected samples) were subjected to beta-carotene bleaching antioxidant activity test. Milk thistle dietary supplements that contain silymarin are widely marketed and used in the U.S.A and other countries for liver enhancement and recovery. More recently, silymarin has also been identified as a possible antiviral for the treatment of hepatitis C virus (HCV) infection. To assess different brands of commercially sold milk thistle, 45 products were collected from local stores and analyzed for their silymarin content, antioxidant activities and anti-HCV activity. Rumex dentatus L. and Rumex vesicarius L. of the family Polygonaceae, are edible herbs growing wild in Egypt. There are few phytochemical studies found in the literature describing the chemical constituents of the two described species. Their lipoid constituents were examined to determine their essential oil and fatty acid composition. Both extracts were also tested for their radical scavenging activity. We investigated three groups of natural herbal antioxidants . One group related to essential oils showed the active antioxidant is mostly related to monoterpenes (or phenolic compounds) and ciscoterpenes. With silymarin , the active antioxidant chemicals are polyphenolic compounds. With the Rumnex , they showed the possibility of significant antioxidant activity and the chemical groups of most importance were the phenolic compounds and omega-3 poly unsaturated fatty acids. We investigated three groups of natural herbal antioxidants. One group related to essential oils showed the active antioxidant is mostly related to monoterpenes (or phenolic compounds) and ciscoterpenes. With silymarin, the active antioxidant chemicals are polyphenolic compounds. With rumnex, the chemical group of most interest were the omega-3 poly unsaturated fatty acids. |
