Abstract
Highly unsaturated fatty acids such as γ-linolenic and eicosapentaenoic acids are now synthesized in large quantities by microorganisms but production methods of arachidonic acid are still inadequate due to its low yield for each type of medium used. To obtain lipids containing arachidonic acid at high efficiency, a detailed study was made of the conditions for incubating Mortierella alpina on potato paste-dextrose medium, addition of trace metals, thickness of the medium layer and pH. Mycelium and pellicle were found to grow on a medium, 2 mm thick, containing 6% dextrose and CaCl2·2H2O 750 mg/kg medium at 20°C for 20 d. Fatty acid analysis of the lipids extracted from the dried cell indicated the yield of arachidonic acid to be 13.1 g/kg medium.
