Chemiluminescence Determination of the Total Antioxidant Capacity of Rosemary Extract

Total antioxidant capacity (TAC) of some Rosmarinus officinalis L. (rosemary) extracts was investigated by an “in batch” analytical method based on chemiluminescence (CL). This method is based on a CL reaction between luminol and hydroxyl radicals generated by the hydrogen peroxide in the presence of Co(II) ions complexed with ethylene diamine tetraacetic acid (EDTA) disodium salt, according to a Fenton-type reaction. The method allows for TAC determination in 1 x 10-5 – 2.5 10-3 moles L-1domain of gallic acid concentration and with a relative standard deviation (RSD) = 2.53% (n = 10) for 8 x 10-4 M gallic acid concentration. The TAC values determined for the analyzed rosemary extracts ranged between 1.6 and 4.58 grams of gallic acid equivalents/100 g dw plant. The employed analytical method was verified by applying the standard addition method and a good precision was established.