Spectral shifting of UV-A wavelengths to blue light for enhancing growth rate of cyanobacteria

This study investigates the modification of UV-A radiation for enhancing the growth rate of Synechococcus species in a simulated photobioreactor made of UV-stabilized polycarbonate (PC) plates. Uvitex OB as was dissolved in a poly(methyl methacrylate) (PMMA)-based resin and the mixture was applied as a coating to shift the UV-A radiation to photosynthetically active radiation (PAR). The feasibility of applying the Uvitex OB in a PMMA-based resin, which was used as fluorescent layer to shift UV-A to PAR range, was explored. For this purpose, a variety of concentrations of Uvitex OB in resin were prepared and coated on PC sheets which were placed between the radiation source and the culture flask. Compared to the uncoated PC sheet, the PC panels coated with a few number of the wavelength shifter layer caused an approximately 4-fold increase in cell number during the same culture period.