[Generation of active forms of oxygen by antibiotics of the tetracycline series during tetracycline catalysis of oxidation of ferrous iron].

During oxidation of Fe(2+) catalyzed by tetracyclines there was recorded lucigenin, activated chemiluminescence evident of generation of the oxygen radicals. It was also observed that during the Fe(2+) oxidation by the molecular oxygen catalyzed by tetracyclines there generated hydrogen peroxide which accelerated the Fe(2+) oxidation recorded photometrically by the formation of strongly absorbing tetracycline complexes with Fe(2+). In the presence of ascorbate reducing Fe(2+) in the complexes with tetracyclines and their subsequent oxidation there generated radicals modifying the antibiotic molecules evident from a change in their absorption spectra after the respective incubation. The results offered a pattern describing the mechanism of the tetracycline toxic effect on biological objects.