通过对产冠毒素新菌株洋葱假单胞菌Pseudomonas cepacia Y57培养温度和时间的研究,发现菌株Y57在碳源充足的情况下,不同培养温度对菌株的生长影响不明显,但影响菌株的产素能力,以32~18℃的变温培养为佳;接着运用正交试验确定了菌株的最佳培养基配方,即:葡萄糖(20g/L),蛋白胨(1.5g/L),FeCl3(15μmol/L),KH2PO4(4.0g/L),K2HPO4(1.8g/L),MgSO4·7H2O(0.2g/L);最后根据试验结果,确定了摇瓶发酵的最适条件为:采用最佳培养基配方,32℃培养1d,降温至18℃发酵2d,冠毒素的效价由优化前的98μg/mL提高到128μg/mL,提高了30%左右。
An experiment was conducted to study the effect of fermentation temperature and time on growth and coronatine production of Pseudomonas cepacia strain Y57. The result revealed that in contrast with the change of growth, the difference of coronatine production was noticeable under different culture temperatures for strain Y57 when the carbon source was sufficient, and the optimum fermentation temperature range was from 32 ℃ to 18 ℃. The orthogonal experiment result suggested that the suitable medium for coronatine produced by strain Y57 during shake-flask fermentation are as follows: glucose(20 g/L), peptone( 1.5 g/ L), MgSO4 ·7H2O (0.2g/L),FeC13(15 μmol/L), KH2PO4(4.0 g/L) , K2HPO4(1.8 g/L). In conclusion, the optimum fermentation conditions are: viz. fermentating 3 d, temperature from 30 ℃ ld to 18 ℃ 2 d, the suitable medium aforementioned. Under these conditions the yield of coronatine was increased by about 30% from 98 μg/mL to 128 μg/mL.