Effects of nutrients concentration and salinity on the growth and total carotenoids accumulation in the microalgae Tetradesmus obliquus

Abstract

In this study, effects of nutrients concentration, including nitrogen (N) and phosphorus (P), and salinity (NaCl) on the growth and total carotenoids accumuslation of the microalgae Tetradesmus obliquus isolated from freshwater bodies in Danang were investigated. The results showed that in BG11 medium with 120 mgN.L-1, 5.43 mgP.L-1 and BG11 medium with 260 mgN.L-1, 12.21 mgP.L-1, T. obliquus have demonstrated the greatest growth rates of 0.298 ± 0.01 day-1 and 0.252 ± 0.20 day-1, respectively. Moreover, under these culture conditions, the highest total carotenoids accumulation was also obtained with an average efficiency of 0.80 ± 0.13% and 0.49 ± 0.18% of dry biomass, respectively. In addition, NaCl was identified to inhibit microalgae growth only at small concentrations from 0.01 to 0.6 M.