Production potential of eicosapentaenoic acid by the diatom Nitzschia laevis

To investigate the production potential of eicosapentaenoic acid (EPA) by t he diatom Nitzschia laevis, the growth characteristics and fatty acid compo sition of the cells were studied under photoautotrophic, mixotrophic and he terotrophic conditions of growth. The specific growth rate and maximum biom ass concentration were respectively 0.466 d(-1) and 2.27 g l(-1) for mixotr ophic culture, 0.344 d(-1) and 2.04 g l(-1) for heterotrophic culture, and 0.167 d(-1) and 0.5 g l(-1) for photoautotrophic culture, respectively. As for EPA production, the yield and productivity were respectively 52.32 mg l (-1) and 10.46 mg l(-1) d for mixotrophic culture, 35.08 mg l(-1) and 6.37 mg l(-1) d for heterotrophic culture, and 6.78 mg l(-1) and 3.39 mg l(-1) d for photoautotrophic culture, respectively. Results suggest that mixotroph ic culture is the most suitable growth mode for the production of EPA by th e diatom Nitzschia laevis. The results are useful for the development of a cost-effective fermentation process for EPA production by Nitzschia laevis.