Abstract
BACKGROUND: The fate of veterinary antibiotics in manure digesters is of great concern because of poor biomethane recovery and potential development of antibiotic resistant bacteria in the environment. RESULTS: Manure samples collected from therapeutically treated cattle (a standard veterinary practice of 50 mL OTC solution as 20mgkg-1 cattle weight) were used in digestion studies. The methane yields of OTC-medicated two-phase and single-phase digesters were 99±8 and 72±9 mL CH4 g-1 VS in the presence of 3.11±0.12 and 3.07±0.14mg OTC L-1, respectively; whereas, non-medicated two-phase and single-phase digesters had 43% and 52% higher methane yields, respectively. Fluorescence in situ hybridization results indicated that the relative abundance of Firmicutes and Gammaproteobacteria was negatively correlated with the presence of OTC. Methanobacteriales seemed to be a resistant order of methanogenic Archaea to OTC and comparatively higher methane yield in two-phase non-medicated cattle manure digester might be the result of the poor cell activity of Methanosarcinales in two-phase OTC-medicated cattle manure digester. CONCLUSION: Higher OTC removal and biomethane production were achieved by two-phase configuration, thus, it can be an alternative to treat antibiotic-medicated manures in full-scale applications in order to reduce its adverse effects.
Original language | English |
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Pages (from-to) | 806-814 |
Number of pages | 9 |
Journal | Journal of Chemical Technology and Biotechnology |
Volume | 91 |
Issue number | 3 |
DOIs | |
Publication status | Published - 1 Mar 2016 |
Bibliographical note
Publisher Copyright:© 2015 Society of Chemical Industry.
Keywords
- Biogas
- Cattle manure
- Fluorescence in situ hybridization (FISH)
- Microbial activity
- Oxytetracycline (OTC)
- Two-phase anaerobic digestion