Optimization of TAP media and fatty acid analysis of arctic Chlamydomonas sp. KNM0029C for biodiesel production

Abstract

Microalgae are considered as promising sources for biofuel production. In cold temperature, it is difficult to maintain proper culture condition for outdoor mass cultivation. The Arctic microalgae (KNM0029C) isolated from sea ice near Dasan Station in Ny-Alesund was analyzed to evaluate the optimal growth condition and lipid contents for biodiesel production. Biodiesel produced by polar microalgae could be used in cold countries, because it has advantages that clogging can be prevented in the fuel supply due to high content of polyunsaturated fatty acids which lower the melting point of biodiesel. In this study, we visualized intracellular lipid formations of Arctic KNM0029C, and analyzed contents of fatty acids by using GC. In addition, to enhance the cell mass and lipid production of KNM0029C, we optimized medium component of Tris-acetate-phosphate (TAP). In conclusion, Arctic Chlamydomonas sp. KNM0029C has an optimal growth temperature of 4°C, reaching densities up to 1.4 × 107 cells per mL and main fatty acids contents were C18:1, C18:2, C18:3, and C20:2 at 4°C and its maximum lipid production reached 178.6mg L-1 which was 2.3-fold higher than that of C. reinhardtii CC-125 as mesophilic strain. When KNM0029C was cultured in optimized TAP medium, total cell numbers and lipid production were increased to ~35% and ~10%, respectively. The results of the present study could potentially contribute toward large-scale lipid production at low temperatures. [The research was supported by a grant from KOPRI (PE16390)]