EVALUATION OF ANTIOXIDANT CAPACITY OF Cinnamomum sp. BY ELECTROANALYTIC AND SPECTROPHOTOMETRIC METHODS

Growing concern about free radicals is due to oxidative processes associated with physiological damage. Thus, the consumption of functional foods and use of plants with antioxidant capacity is widespread. Given the importance of determining antioxidant capacity in relation to the therapeutic effect, this study aimed to evaluate cinnamon extract (Cinnamomum sp.) in commercial samples by spectrophotometric and voltammetric methods. The spectrophotometric methods performed were DPPH (1,1-diphenyl-2-picrihydrazine) and ABTS (2,21-azinobis- (3-ethylbenzothiazoline-6-sulfonic acid) radical sequestration assays. For the electrochemical experiments, three electrode system was used, consisting of carbon paste electrode, platinum wire and Ag/AgCl/KClsat, representing the working, auxiliary and reference electrodes, respectively. The electroanalytical methods used were differential pulse voltammetry, square wave and cyclic voltammetry. The extracts were prepared in ethanolic solution. Calibration curves with resveratrol and gallic acid were calculated with DPPH and ABTS to quantify their equivalent amounts in the analyzed extract. The correlation between the electrochemical approach and the total phenols calculated by the ABTS and DPPH methods was 0.95 and 0.86 respectively, with 1 being an ideal correlation. However, the correlation between spectrophotometric methods was 0.75. The samples were analyzed by mass spectrometry and the main markers found were cinnamaldehyde, coumarin and eugenol. Cinnamon showed high antioxidant capacity, in agreement with the results obtained in other studies, emphasizing its importance as food.