Advanced oxidation processes on doxycycline degradation: monitoring of antimicrobial activity and toxicity

Author(s)

Spina-Cruz, Mylena ; Maniero, Milena Guedes ; Guimaraes, Jose Roberto

• Document type: Journal article
• Source: Environmental Science and Pollution Research; v. 26, n. 27, p. 16-pg., 2019-09-01.

Abstract

Advanced oxidation processes (AOPs) have been highly efficient in degrading contaminants of emerging concern (CEC). This study investigated the efficiency of photolysis, peroxidation, photoperoxidation, and ozonation at different pH values to degrade doxycycline (DC) in three aqueous matrices: fountain, tap, and ultrapure water. More than 99.6% of DC degradation resulted from the UV/H2O2 and ozonation processes. Also, to evaluate the toxicity of the original solution and throughout the degradation time, antimicrobial activity tests were conducted using Gram-positive (Bacillus subtilis) and Gram-negative (Escherichia coli) bacteria, and acute toxicity test using the bioluminescent marine bacterium (Vibrio fischeri). Antimicrobial activity reduced as the drug degradation increased in UV/H2O2 and ozonation processes, wherein the first process only 6 min was required to reduce 100% of both bacteria activity. In ozonation, 27.7 mg L-1 of ozone was responsible for reducing 100% of the antimicrobial activity. When applied the photoperoxidation process, an increase in the toxicity occurred as the high levels of degradation were achieved; it means that toxic intermediates were formed. The ozonated solutions did not present toxicity. (AU)

• FAPESP's process: 13/04656-8 - Degradation of pharmaceuticals by peroxidation combined with ultraviolet radiation and ozonation: antimicrobial activity and toxicity
• Grantee: José Roberto Guimarães
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/07817-2 - Degradation of sulfonamides and tetraciclines by UV/H2O2 and O3: evaluation of antimicrobial activity and toxicity
• Grantee: Milena Guedes Maniero Ferreira
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• FAPESP's process: 13/09543-7 - Residues of veterinary drugs in the environment
• Grantee: Susanne Rath
• Support Opportunities: Research Projects - Thematic Grants