Exploiting Biohydrogen Pathways of Cyanobacteria and Green Algae: An Industrial Production Approach

Abstract

Hydrogen is viewed as a clean and sustainable energy alternative of future that may change the present carbon-based economy to hydrogen-based economy in the years to come. Biohydrogen production by various microorganisms has emerged as a new area in energy generation that is moving ahead for industrial application. Cyanobacteria and green algae are photoautotrophic microbes that are capable of hydrogen generation by direct or indirect biophotolysis and photofermentation. Hydrogen production is mediated by hydrogenase and nitrogenase enzyme, both of which are oxygen sensitive. Various pathways and strategies of hydrogen production by these photoautotrophic microorganisms have been discussed in this chapter along with approaches to enhance hydrogen yields for prolonged duration using different photobioreactor designs. The possibility of using cyanobacteria and green algae for integrating hydrogen production with wastewater treatment and environmental implications thereof has also been discussed. In biological hydrogen production, there are no greenhouse gas emissions; thus, switching over to hydrogen as a future energy fuel would also help mitigate the global climate change problem.