Metabolic engineering approaches for scale-up of fermentative biohydrogen production–A review

Significant efforts are being made to produce biofuels to replace fossil fuels and address the issues caused by global climate change. Due to its potential better conversion efficiency to useable power, decreased emission of pollutants, and high energy density, H₂ is one of the prospective options that are seen as a desirable future clean energy carrier. Although there are numerous technologies available for producing H₂, this review concentrates on fermentative H₂ production techniques, their drawbacks, and current developments. While being a promising method, fermentative strategies still have several drawbacks, including low H₂ production yields. Many approaches have been used to address these issues; among them, the field of metabolic pathway engineering has made enormous strides. To improve H₂ generation, this paper reviewed and discussed several metabolic pathways and modified strains. As well as the challenges involved in H₂ scale-up from a laboratory setting to a commercial scale.