Performance of bioelectrochemical systems inoculated with Desmodesmus sp. A8 under different light sources

Light source can affect the stomata opening, photosynthesis process, and pigment content in microalgae cells. In this study, growth rate, chlorophyll a (chl a) content, and electrogenic capability of Desmodesmus sp. A8 were investigated under incandescent and fluorescent lamps. Growth rate, productivity, and chl a content of strain A8 exposed to incandescent light were recorded as 0.092 ± 0.010 day⁻¹, 0.019 ± 0.008 g L⁻¹ day⁻¹, and 15.10 ± 1.40 mg L⁻¹, which decreased to 0.086 ± 0.006 day⁻¹, 0.012 ± 0.004 g L⁻¹ day⁻¹, and 10.06 ± 1.59 mg L⁻¹, respectively, under fluorescent light. The stable current density of bioelectrochemical systems inculcated with strain A8 under incandescent and fluorescent lamps were 249.76 and 158.41 mA m⁻² at −0.4 V vs. Ag/AgCl, coupling with dissolved oxygen within biofilm decreasing from 15.91 to 10.80 mg L⁻¹. This work demonstrated that illuminating microalgae under an incandescent lamp can improve biomass production and electrogenic capabilities.