Degradation and Elimination of Various Sulfonamides during Anaerobic Fermentation: A Promising Step on the Way to Sustainable Pharmacy?

Abstract

Antibiotics, most notably sulfonamides and tetracyclines, are frequently used veterinary pharmaceuticals in animal husbandry. A new field of application for animal manure is in biogas plants for generating environmentally friendly energy. As a result, antibiotics contained in manure may still reach the environment as fermentation residues are also used on agricultural fields as fertilizers. Therefore, in fermentation tests seven sulfonamides and trimethoprim were investigated regarding their elimination behavior during a five-week fermentation process. Sulfadiazine, sulfamerazine, sulfamethoxazole, sulfadimethoxine, and trimethoprim were nearly completely eliminated while sulfathiazole, sulfamethazine, and sulfamethoxypyridazine showed persistence. For sulfadiazine it was possible by means of mass spectrometry to identify and partly quantify a metabolite, emerging from a hydroxylation at the pyrimidine ring, 4-OH-sulfadiazine. Furthermore, a microbial inhibition test showed a substantial reduction in the antimicrobial activity of the metabolite compared to the parent compound. Thus, the fermentation process may be an efficientwayto reduce the load of selected veterinary antibiotics finding their way into the environment Degradable drugs such as sulfadiazine may therefore, at least in the aspect of residual antibiotic activity of metabolites, be considered as environmentally friendly drugs.

Removal of antibiotics and antibiotic resistance genes from domestic sewage by constructed wetlands: Effect of flow configuration and plant species

“…There were no sulfonamides and ionophores detected in the substrate and plant samples, suggesting degradation (and transformation) played a more important role in the aqueous removal of these two classes of antibiotics than substrate adsorption and plant uptake. The results are in good agreement with the previous reports that sulfonamides (including TMP used as sulfonamides potentiator) and MON are easily biodegradable (Xu et al, 2007;Mohring et al, 2009;Li and Zhang, 2010;García-Galán et al, 2011;Sun et al, 2014). For the detected 3 macrolides, adsorption onto substrates and uptake by plants only accounted for a minor percentage of the total mass loading into each CW.…”

Occurrence and fate of eleven classes of antibiotics in two typical wastewater treatment plants in South China

“…Higher removals have been reported for trimethoprim during nitrification process (Batt et al, 2006b;Perez et al, 2005) and anaerobic fermentation and sludge digestion (Gobel et al, 2005;Mohring et al, 2009), but it showed high persistence towards aerobic biological treatment (b20%) (Suarez et al, 2010). High aqueous removal percentage of trimethoprim in anoxic unite (39.5% and 53.2%) in plant A and in oxidation ditch (14.3% and 66.9%) in plant B further suggests that the removal of trimethoprim was attributed to the anoxic and anaerobic biodegradation process.…”

“…These results indicated that sulfonamides were mainly biodegraded in the WWTPs. Sulfonamides (such as sulfamethoxazole, sulfamethazine, and sulfadiazine) have been reported to be easily biodegradable (Jesus Garcia-Galan et al, 2011;Li and Zhang, 2010;Mohring et al, 2009;Xu et al, 2011), and transformed in anaerobic sludge digestion (Gobel et al, 2005), while Suarez et al (2010) reported that sulfamethoxazole was minimally biodegradable (b 20%) under aerobic biological treatment. Previous papers also reported that for sulfonamides were little adsorbed onto the sludge, with sludge solid K d,solid ranging from 28.6 to 110 L/kg (Table S1).…”

Biodegradation of sulfamethoxazole: current knowledge and perspectives

“…The results have demonstrated that anaerobic digestion (fermentation) is a very successful method to degrade SMX in sludge and manure with measured removal rates of >99 % after 10 to 35 days in batch-/lab-scale experiments. This impressive SMX degradation was achieved with both low (4 to 400 μg/L) (Carballa et al 2007) and high (2 to 10 mg/L) (Mohring et al 2009) initial SMX concentrations. In addition to these sludge and manure fermentation studies, anaerobic and anoxic column tests (as described in the previous section) were carried out with surface water containing 0.25 and 4.5 μg/L SMX in order to model microbial degradation during bank filtration.…”