Accurate assessment of the effect of Rhodamine 6G solution as a spectral converter on biomass production of microalgae Chlorella sp., nitrate uptake, and energy consumption by the light source.

Abstract

Spectral conversion of light introduced as a new technique to manage incoming light photons into the culture medium of photosynthetic microorganisms which can increase biomass production. In this work, a much more accurate value of the effect of spectral conversion on the growth of Chlorella sp. was obtained. For this purpose, the light source and Rhodamine 6G solution, as a spectral converter, was placed in the center of the culture flask, which was covered with aluminum foil. The loss of photons was largely avoided due to the additional homogeneous distribution of light. Modification of white light using the solution has increased biomass productivity up to 300%. Also, for biomass productivity of 1mg L-1day-1, the energy consumption of the white light source was reduced up to 75%. Nitrate uptake has also increased up to 28%, and intracellular lipid content has decreased, as well.