二十碳五烯酸的菌种选育及发酵条件

利用含亚麻子油的斜面培养基连续传代和逐渐降低培养温度，诱导筛选的方法，从大量丝状真菌中选育到一株产二十碳五烯酸（all－cis－5、8、11、14、17－eicosopnthenoicacid）较高的被孢霉菌（Motierellasp．）SM481。研究得到最适培养基及最适培养条件。在最适培养及产二十碳五烯酸条件下，细胞干重和二十碳五烯酸产量分别为28．8g／L和0.127g／L。

STRAIN SCREENING AND THE FERMENTATTION CONDITIONS OF EICOSAPENTAENOIC ACID

Mortierella sp. SM481 which can produce relatively high yield of eicosapentaenoic acid (EPA) was isolated. The optimumal culture medium composition (%) was: glucose 8; linseed oil 2; yeast extract 2; KNO3 O.5; KH2PO4 0.3, FeCl3·6H2O 0.002; MgSO4·7H2O 0.00003; NaCl, 0.02. The culture showed maximum EPA content at 28℃ for 130h, 150r /min, 200mL medium / 1000mL flask. The existence of linseed oil in the medium can stimulate the synthesis of the EPA efficiently and the limited glucose was indispensable to the EPA production. Under the optimum culture conditions, the dry cell weight and EPA content were 28.8g/L and 0.127 g/L respectively.