|Stimulation of in vitro anaerobic oxidation of methane rate in a continuous high-pressure bioreactor|Zhang, Y.; Henriet, J.-P.; Bursens, J.; Boon, N. (2010). Stimulation of in vitro anaerobic oxidation of methane rate in a continuous high-pressure bioreactor. Bioresour. Technol. 101(9): 3132-3138. dx.doi.org/10.1016/j.biortech.2009.11.103
In: Bioresource Technology. Elsevier: Barking. ISSN 0960-8524, meer
Mud volcano Anaerobic methanotroph archaea Sulphate reducing bacteria Gulf of Cadiz
Anaerobic oxidation of methane coupled to sulphate reduction (SR-AOM) prevents oceanic methane emissions and is considered as a major environmental process in the deep-sea sediments. To stimulate in vitro SR-AOM activity, we designed a (continuous) high-pressure bioreactor system. Fed-batch mode incubations showed that the elevated methane pressure stimulated SR-AOM activity: when the methane pressure increased from 1 to 4.5 to 8 MPa, the initial SR-AOM activity increased from 3.46 to 8.64 to 9.22 µmol sulphide production/gdw/day; the apparent affinity (Km) for methane was 37 mM. However, in each fed-batch mode incubation, there was an inhibitory effect observed after 2 days, probably due to the accumulation of sulphide and the increase of pH. When the reactor was operated in a continuous mode, the SR-AOM activity was constantly increasing within 18 days at both 1 and 8 MPa pressures.