Synthesis and characterization of fluorescent dyes and their applications for the enhancement of growth rate of Chlorella vulgaris

Abstract

Four fluorescent dyes were carefully designed to convert wavelengths of light specifically favourable for microalgal growth in which a portion of white light was converted from green (500 – 580nm) to orange-red (580 – 650nm). Synthesized dyes were applied to microalgae cultivation system by two methodologies: (1) light-converting layer, and (2) light-converting medium in which the dyes were dissolved in either ethanol or water to form light-converting layer between microalgae cultures and the light source. Under converted light provided by both methods, Chlorella vulgaris cultures showed maximum increase in lipid productivity by 13.00% and 17.15%, and biomass productivity by 31.65% and 37.66% compared to the control. Overall, the cultivation results confirmed beneficial effects of modified light on microalgae cultures both on their lipid and biomass productivities. Note that both growth parameters achieved higher performance in the light-converting medium thereby the effectiveness of the cultivation method was validated.