Selective inhibition by 2-bromoethanesulfonate of methanogenesis from acetate in a thermophilic anaerobic digestor

Abstract

The effects of 2-bromoethanesulfonate, an inhibitor of methanogenesis, on metabolism in sludge from a thermophilic ( 58°C) anaerobic digestor were studied. It was found from short-term experiments that 1 μmol of 2-bromoethanesulfonate per ml completely inhibited methanogenesis from 14CH3COO-, whereas 50 μmol/ml was required for complete inhibition of 14CO2 reduction. When 1 μmol of 2-bromoethanesulfonate per ml was added to actively metabolizing sludge which was then incubated for 24 h, it caused a 60% reduction in methanogenesis and a corresponding increase in acetate accumulation; at 50 μmol/ml it caused complete inhibition of methanogenesis and accumulation of acetate, H2, and ethanol.