Salacia campestris root bark extract: peroxidase inhibition, antioxidant and antiradical profile

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Reactive oxygen species (ROS) and free radical species have been implicated in initiating or accompanying many diseases in living organisms; there is thus, a continual need for antioxidants molecules to inactivate ROS/free radicals. Many studies of plants crude extracts have demonstrated free-radical scavenging and antioxidant action. Salacia species have long been used, in several countries, as traditional medicines against certain diseases and for their anti-inflammatory properties. In this Study, Salacia campestris Walp (Hippocrateaceae) root bark ethanol extract (ScEtOH) was assessed for its ability to scavenge free radicals and reactive oxygen species; the results were expressed as percentage inhibition of the active species. ScEtOH was efficient against studied species: DPPH radical (obtained inhibition = 30%), ABTS(center dot+) (IC(50) = 1.8 +/- 0.8 mu g/mL), HOCI (IC(50) = 1.7 +/- 0.1 mu g/mL), O2(center dot-) (obtained inhibition = 32%), and NO(center dot) (obtained inhibition = 18%). Peroxidase activity inhibition was evaluated through the guaiacol oxidation reaction catalyzed by hemin, HRP and. myeloperoxidase (MPO); data showed that ScEtOH at 10 mu g/mL led to 54 and 51% of inhibition, respectively, for the hemin and HRP systems. In the MPO system, ScEtOH promoted a 50% inhibition at 8.9 mu g/mL, whereas quercetin, a powerful MPO inhibitor, inhibited this system at 1.35 mu g/mL.