“…The production of hydrogen in a sustainable way is another requirement for the hydrogen economy. Among others, (photo)electrochemical water splitting (Tee et al, 2017) but also biological methods are envisioned (Akhlaghi and Najafpour-Darzi, 2020;Hidalgo and Martín-Marroquín, 2022). In particular, hydrogen production in the dark fermentation process by a bacterium or a consortium of several bacteria from a wide range of food and agricultural feedstocks could become one of the eco-friendliest processes (Sarangi and Nanda, 2020;Xu et al, 2022).…”