Biohydrogen production by Lyngbya perelegans: Influence of physico-chemical environment

Biohydrogen production by a non-heterocystous cyanobacterium Lyngbya perelegans was studied under varied physico-chemical conditions including oxic/anoxic, light/dark period, light intensity, temperature, pH and salinity. Some important biological characteristics of the species that favored its selection as a hydrogen producing organism included its dense biomass in the culture, moderately good chlorophyll-a and carotenoid concentrations, high glycogen content, and high hydrogenase activity at its mid log phase (7d). Biohydrogen production by the cyanobacterium was found to be significantly influenced by its physico-chemical environment. H2 production by the species could be increased 1.4 times by optimizing the light/dark duration, light intensity, pH and temperature, while maintaining anoxic conditions and supplementing the medium with a low concentration of salt.