Evaluation of the Detoxifying Ability of Humic Acids in Relation to Antibiotics

Abstract

The detoxifying ability of lowland peat humic acids at 10 to 110 mg/l concentration with respect to tetracycline, doxycycline, and cefotaxime was studied by bioanalysis on Escherichia coli K-802 strain. It was confirmed that, according to sensitivity to the presence of humic substances, the studied antibiotics were ranked as follows: cefotaxime > doxycycline > tetracycline. Humic acids were found to exhibit maximum detoxifying effect against cefotaxime in the entire concentration range. It was found that detoxification with respect to cefotaxime occurs mainly due to the binding of the antibiotic into non-toxic complexes, and for doxycycline and tetracycline – due to the inherent action of humic acids on the test object with a minimal contribution to binding. Enhancement of antimicrobial effect in the presence of humic acids above 60 mg/litre for tetracycline was recorded.