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

ABSTRACT

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.

KEYWORDS:

• Bioelectrochemical systems
• biofilms
• dissolved oxygen
• light source
• microalgae

Acknowledgments

The authors thank Valerie Gibson from the Institute of Urban Environment, Chinese Academy of Sciences, and Nathan Pilkington from the University of Nottingham for the careful editing of this article.

Funding

This work was supported by High Level Talent Program of Xiamen University of Technology (E2015028), National Natural Science Foundation of China (41471260), and Young Teacher Project of Fujian Province (No. JA15372).