Salinity-dependent changes in growth and fatty acid composition of new Arctic Chlamydomonas species, ArM0029A

Abstract

Arctic microalgae are considered alternative sources for biodiesel production in cold climates. In this study, we describe the isolation of a novel Chlamydomonas sp. from Arctic sea ice, which we named ArM0029A, and the development of a new culture medium, HAP3, that allows greater cell growth and density than seawater-based media. The fatty acid composition of ArM0029A was characterized at various sodium chloride (NaCl) concentrations. Culture at low NaCl concentration (7 ‰), relative to seawater, enhanced growth and fatty acid accumulation of ArM0029A. Total fatty acid content reached a maximum of approximately 27 % of dry weight at 7 ‰ NaCl without nitrogen, and unsaturated fatty acids, such as C16:4, C18:2, and C18:3, were predominant. Interestingly, the proportion of C16:3 was significantly induced in ArM0029A by salt stress. These findings indicate that use of ArM0029A may be feasible for production of lipids, especially polyunsaturated fatty acids, under cold climatic conditions via adjustment of NaCl concentrations.