E. Adamek, W. Baran, L. Krumpholtz, B. Pelczar
Medical University of Silesia in Katowice, Katowice, PL

A STUDY ON SUSCEPTIBILITY OF TYLOSIN TO DEGRADATION BY PHOTOCHEMICAL REACTIONS


Tylosin is a macrolide antibiotic commonly used in animal breeding. Its residues with post-production wastes can enter the environment. That fact favors the development of drug resistance of the environmental microorganisms to macrolides and then in pathogens. The objective of the study was to determine the susceptibility of tylosin to a photodegradation initiated by UVA irradiation. The process was conducted in the presence of the selected catalytic system. The kinetics of tylosin photodegradation caused by UVA irradiation only and in the presence of TiO2-P25 (Aeroxide®), TiO2-P25/FeCl3 and FeCl3 during UVA irradiation was compared. The experiments were carried out under aerobic and anaerobic conditions (under an argon atmosphere). It was found that the UVA irradiation of tylosin solution caused an antibiotic izomerization only. The tylosin degradation was observed during irradiation of the solutions with photocatalyst except for the experiment with TiO2-P25 under anaerobic conditions. The rate of photodegradation increased as follows:
TiO2-P25(O2) << TiO2-P25/FeCl3 (Ar) < TiO2-P25/FeCl3 (O2) << FeCl3 (Ar) < FeCl3 (O2)

Keywords:tylosin, macrolides, environment, photocatalysis.