高山被孢霉常温高产EPA的研究

Eicosapentaenoic acid is an omega-3 long chain polyunsaturated fatty acid with special physiological functions, such as anticoagulant, anti-cardiovascular disease and hypolipidemic. It has many applications on health care products, food and feed industry. Oleaginous fungus Mortierella alpina is an industrial strain of arachidonic acid production, but the amount of EPA is very low.Omega-3 fatty acid desaturase is a key enzyme in the synthesis of omega-3 long chain polyunsaturated fatty acids and can catalyzed AA to generate EPA. To enhance EPA production, we heterologous expressed the Pythium aphanidermatumω-3 fatty acid desaturase PaD17in Mortierella alpina and obtained six recombinantstrains.The EPA yield of the recombinant strain CCFM695 was up to 600 mg/Lat room temperature.The effects of different carbon and nitrogen sources on the accumulation of EPA were studied by single factor and orthogonal experiments. Results showed that the yield of EPA was up to 1.7 g/L under the condition of glucose and defattedsoybean meal, about 3 times more than the original fermentation conditions.