Photosynthesisis the process by which solar energy is converted into chemical energy in theform of complex carbohydrates and ATP. With growing interest inphotosynthesis as a potential renewable- energysource, Bio-photo-electrochemical cells (BPEC) were designed andfabricated with the purpose of light energy transformation into electricalpower or even hydrogen fuel.
InBPEC systems, one of the factors limiting power outputs and efficiency is themolecular damage caused to the photosynthetic protein machinery due to intenseradiation exposure for long time periods (e.g. Photoinhibition). Tocope with radiation damage and minimize photoinhibition,certain organisms that dwell in high radiation areas have developed specialrepair mechanisms (e.g. photoprotection).One such organism is the unicellular green micro-algae Chlorella ohadii,which was isolated from soil-crust beds in the Nitzanadesert, Israel. Originating from an arid desert area, C. ohadii isa good candidate for improving our BPEC set-up, having a robust photoprotectionmechanism and fast proliferation rate. C. ohadii cells and isolatedthylakoid membranes have generated stable photocurrents inthe BPEC system, with ferricyanide asthe exogenous electron mediator. The majority of current originates fromphotosynthesis, as it was inhibited upon addition of DCMU.
Inthis study, we established and evaluated the power-output andperformance of an algal BPEC system with C. ohadii cellsor thylakoids, demonstrating its potential for sustainable bio-energyproduction.