Lipid accumulation on optimized condition through biomass production in green algae

Abstract

Microalgae, mainly green algae, are well known as sources of lipids for food, feed, and energy. As our institution owned microalgae collections, we performed microalgae screening to find candidate/s, producing high lipid content. In this research, microalgae were screened by various media, and then the medium was optimized. Larger scale cultivation was done in order to find out the yield of the biomass production and lipid content. The condition with phosphate buffer was applied to increase the lipid accumulation. The lipid content was analyzed by Nile red staining. As a result, Chlamydomonas reinhardtii and Chlorella vulgaris showed high biomass production in the Tris-Acetate-Phosphate (TAP) medium. Chlamydomonas reinhardtii at four times concentration and C. vulgaris at the initial concentration of TAP medium demonstrated the most increased biomass production. The maximum biomass production and lipid content was 0.9 g/l and 31% for C. reinhardtii and 1.7 g/l and 27% for C. vulgaris, respectively. Under starvation, the lipid content was increased up to 52% for C. reinhardtii and 34% for C. vulgaris, which were higher than their control. From this study, the TAP medium was found to have the most increased biomass production, and starvation enhanced lipid accumulation.