EFFECTS OF SANGRE-DE-DRAGO FROM CROTON LECHLERI MUELL-ARG ON THE PRODUCTION OF ACTIVE OXYGEN RADICALS

The total reactive antioxidant potential (TRAP) of 'Sangre de Drago' f rom Croton lechleri (Euphorbiaceae) was determined by monitoring the i ntensity of luminol enhanced chemiluminescence enhanced by peroxyl rad icals derived from thermolysis of 2,2'-azo-bis(2-amidinopropane). The TRAP index was calculated as 935.4 +/- 141 mu M, measured as equivalen ts of Trolox concentration. On the other hand, the additive incorporat ion of lower concentrations yielded an instantaneous increase in chemi luminescence, suggesting a prooxidant activity at these levels. DNA su gar damage induced by Fe(II) salts was also used to determine the capa city of the latex to suppress hydroxyl radical-mediated degradation of DNA. As in the case of luminol enhanced chemiluminescence, Sangre de Drago was highly effective in reducing oxidation of DNA at higher conc entrations, but showed an increase in the production of TEARS at lower doses, as compared to the control. Finally, antioxidant activity was tested using hydroperoxide-initiated chemiluminescence in rat liver ho mogenates, and the latex showed an increase in light emission, suggest ing the presence of prooxidant compounds. (C) 1997 Elsevier Science Ir eland Ltd.