Abstract:A simple procedure for the voltammetric detection of antioxidative activity of plant extracts based on the protection from DNA damage at the electrode surface is reported. A disposable electrochemical DNA biosensor fabricated as a carbon-based screen-printed electrode modified by a surface layer of the calf thymus double stranded (ds) DNA was used as a working electrode in combination with a silver/silver chloride reference electrode and a separate platinum auxiliary electrode. The [Co(phen) 3 ] 3+ ion served as the dsDNA redox marker and the [Fe(EDTA)] -complex with hydrogen peroxide under the electrochemical reduction of the iron atom were used as the DNA cleavage mixture. A remarkable antioxidative activity of phenolic antioxidants such as rosmarinic and caffeic acids as standards and the extracts of lemon balm, oregano, thyme and agrimony was found which is quite in agreement with an antiradical activity determined spectrophotometrically using 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical.
HPLC columns with different length, particle size, and chemical properties of sorbent were tested and compared for the application in the development of the universal HPLC assay for determination of phenolic compounds, which could be present in some medicinal plants from the Lamiaceae family (Melissa officinalis, Rosmarinus officinalis, Salvia officinalis, Thymus serpyllum, and Origanum vulgare). More RP-18 columns have been chosen for the simultaneous separation of all phenolic compounds in the study. The basic chromatographic characteristics were evaluated and the HPLC method using one of the suitable columns was validated for all determined analytes. The recommended separation conditions were applied for phenolic compound monitoring in extracts of plant material. Yields of analytes present in all plant samples were evaluated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.