“…MP fermentation at lab scale mostly cultivated in serum bottles, one third of which was the cultivation media, and the headspace was a mixture of oxygen and methane [19,20,41]. While this set-up is useful for fast screening and optimization of different cultivation conditions and feedstocks [15,20,34,38,234,235], they have provided low gas-liquid mass transfer, and hence are not suitable for large scale biomass production. To deal with gas-liquid transfer limitations in MP fermentation, different gas diffuser technologies have been proposed.…”