Beyond the Theoretical Yields of Dark-Fermentative Biohydrogen.

Theoretical hydrogen (H2) yield by dark fermentative route is 12 mol/mol of glucose. Biological H2 production yields of 3.8 mol/mol of glucose by microbes have been reported. Transient gene inactivation in combination with adaptive laboratory evolution strategy has enabled the H2 yield to exceed the stoichiometric production values.