Abstract
Using a methanotrophic consortium (that includes Methylosinus sporium NCIMB 11126, Methylosinus trichosporium OB3b, and Methylococcus capsulatus Bath) isolated from a landfill site, the potential for partial oxidation of methane into methanol through selective inhibition of methanol dehydrogenase (MDH) over soluble methane monooxygenase (sMMO) with some selected MDH inhibitors at varied concentration range, was evaluated in batch serum bottle and bioreactor experiments. Our result suggests that MDH activity could effectively be inhibited either at 40mM of phosphate, 100mM of NaCl, 40mM of NH4Cl or 50μM of EDTA with conversion ratios (moles of CH3OH produced per mole CH4 consumed) of 58, 80, 80, and 43%, respectively. The difference between extent of inhibition in MDH activity and sMMO activity was significantly correlated (n = 6, p < 0.05) with resultant methane to methanol conversion ratio. In bioreactor study with 100mM of NaCl, a maximum specific methanol production rate of 9μmol/mgh was detected. A further insight with qPCR analysis of MDH and sMMO coding genes revealed that the gene copy number continued to increase along with biomass during reactor operation irrespective of presence or absence of inhibitor, and differential inhibition among two enzymes was rather the key for methanol production.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call