Comparison of methane yield of a novel strain of Methanothermobacter marburgensis in pure and mixed adapted culture derived from a methanation bubble column bioreactor

The ongoing discussion regarding the use of mixed or pure cultures of hydrogenotrophic methanogenic archaea in Power-to-Methane (P2M) bioprocess applications persists, with each option presenting its own advantages and disadvantages. To address this issue, a comparison of methane (CH₄) yield between a novel methanogenic archaeon belonging to the species Methanothermobacter marburgensis (strain Clermont) isolated from a biological methanation column, and the community from which it originated, was conducted. This comparison included the type strain M. marburgensis str. Marburg. The evaluation also examined how exposure to oxygen (O₂) for up to 240 min impacted the CH₄ yield across these cultures. While both Methanothermobacter strains exhibit comparable CH₄ yield, slightly higher than that of the mixed adapted culture under non-O₂-exposed conditions, strain Clermont does not display the lag time observed for strain Marburg.