title: Acute effect of erythromycin on metabolic transformations of volatile fatty acid mixture under anaerobic conditions.
abstract: The study explored the acute inhibitory impact of erythromycin on the methanogenic activity of acclimated biomass fed with a volatile fatty acid mixture and acetate alone. Parallel batch reactors were operated for six days, with increasing erythromycin dosing in the range of 1-1000 mg L(-1). Substrate removal was monitored by means of soluble COD and volatile fatty acid (VFA) measurements together with parallel observations on biogas and methane generation. The inhibitory impact was variable with the initial erythromycin dose: At lower doses, the VFA mixture was completely removed but partially utilized, leading to reduced biogas and methane generation, suggesting the analogy of uncompetitive inhibition. At higher doses, propionate utilization was totally impaired and butyrate removal was reduced, but acetate was still fully removed. Remaining VFAs were partly converted to new VFA compound through isomerization and polymerization reactions. High erythromycin doses induced total inactivation of microbial metabolism with negligible methane generation.
authors.affiliation: Istanbul Technical University, Civil Engineering Faculty, Department of Environmental Engineering, 34469 Maslak, Istanbul, Turkey. Electronic address: cetecioglu@itu.edu.tr.
authors.forename: Z
authors.initials: Z
authors.lastname: Cetecioglu
authors.affiliation: Bogazici University, Institute of Environmental Sciences, Rumelihisarustu-Bebek 34342, Istanbul, Turkey.
authors.forename: B
authors.initials: B
authors.lastname: Ince
authors.affiliation: Istanbul Technical University, Civil Engineering Faculty, Department of Environmental Engineering, 34469 Maslak, Istanbul, Turkey.
authors.forename: O
authors.initials: O
authors.lastname: Ince
authors.affiliation: Istanbul Technical University, Civil Engineering Faculty, Department of Environmental Engineering, 34469 Maslak, Istanbul, Turkey; The Science Academy, Besiktas 34453, Istanbul, Turkey.
authors.forename: D
authors.initials: D
authors.lastname: Orhon
mesh_terms: D000085:Acetates / Q000378:metabolism; D000693:Anaerobiosis; D000890:Anti-Infective Agents / Q000633:toxicity; D001419:Bacteria / Q000187:drug effects* / Q000378:metabolism*; D056804:Biofuels / Q000032:analysis; D019149:Bioreactors; D002087:Butyrates / Q000378:metabolism; D004785:Environmental Pollutants / Q000633:toxicity*; D004917:Erythromycin / Q000633:toxicity*; D005232:Fatty Acids, Volatile / Q000378:metabolism*; D008697:Methane / Q000378:metabolism*; D011422:Propionates / Q000378:metabolism
chemical_list: D000085:Acetates; D000890:Anti-Infective Agents; D056804:Biofuels; D002087:Butyrates; D004785:Environmental Pollutants; D005232:Fatty Acids, Volatile; D011422:Propionates; D004917:Erythromycin; D008697:Methane
keywords: Erythromycin; Inhibition; Methanogenic activity; Volatile fatty acids