Antioxidant and Prooxidant Effects of Curcumin, Piperine and Semi-synthetic Amides with Antimycobacterial Activity on the Lipid Oxidation Process

Abstract

Free radical oxidation is considered an important factor in the treatment of tuberculosis. Drugs or treatments with antioxidants are reflected in the literature but the choice of those used for tuberculosis is quite limited. Selected natural and synthetic compounds (hybrid molecules consisting of fenchane scaffold and cinnamoyl like residues attached through amide bond), possessing antimycobacterial activity were studied for their capacity to accelerate or decelerate lipid oxidation process. Three of the compounds under study showed prooxidant activity. To the best of our knowledge, this is the first report about the prooxidant activity of piperine under spontaneous autoxidation conditions. The presence of fenchane scaffold together with the 1,3-benzodioxole fragment, positively affects the activity but we can only speculate about the role of the amide part. Effect of equimolar binary mixtures with curcumin has also been studied. These new results may contribute to the search for efficient bio-antioxidant mixtures in the prevention and elimination of adverse reactions of antibacterial drugs.