在大肠杆菌中克隆表达单增李斯特氏菌(Listeria monocytogenes)磷脂酶C,并进行发酵优化。当接种量为4%时,37℃,200 r/min培养2 h后添加2.5 g/L乳糖,25℃摇瓶诱导发酵26 h,最终获得重组磷脂酶C的活力达到754.6 U/mL。利用该重组磷脂酶C对大豆毛油和菜籽毛油进行脱胶,精炼油中的含磷量分别从216.67mg/kg和183.70 mg/kg下降到3.70 mg/kg和4.50 mg/kg,说明该重组磷脂酶C能够用于不同植物毛油脱胶,可以达到后续精炼工艺要求,同时增加毛油精炼率,在油脂脱胶工艺方面具有较大的应用前景。

In this study,the phospholipase C gene( lm-plcB) from Listeria monocytogenes was cloned and expressed in E. coli and the fermentation conditions was optimized. With 4% inoculation rate,the recombinant strain were cultured for 4 hours at 37 ℃ 200 r / min,then additionally induced with 2. 5 g / L lactose. After incubated for 26 hours at 25℃ in the TB-TH medium,the enzyme activity of the recombinant phospholipase C reached 754. 6 U / mL. The recombinant PLC was used to degum soybean and rice bran crude oil. Finally,the residual phosphorus content in the degummed soybean oil and rice bran oil decreased from 216. 67 μg / kg to 3. 70 μg / kg and 183. 70 μg / kg to 4. 50 μg/kg,respectively. The results showed that the recombinant phospholipase C( lm-plcB) from L. monocytogenes could fulfill the requirement of physical refine of oil,and increase the refining rate,which would have many obvious advantages and good application prospects for the edible oil industry.