磷脂酶A1产生菌株的筛选

Screen of Phospholipase A1 Production Strain

磷脂酶A1是专一水解天然磷脂Sn-1位酰基的酶,可以得到Sn-2酰基溶血磷脂和脂肪酸。磷脂酶在商业上可用于在炼油过程(油脱胶)磷脂的去除。实验以卵磷脂为唯一碳源,从富油土壤中筛选具有较高磷脂酶A1活力的菌株PL-06。以其为出发菌株,从碳源、氮源、无机盐等几个方面对菌株产酶的发酵条件进行了优化。确定菌株PL-06最佳氮源为氯化铵,麦芽糖和卵磷脂为最佳复合碳源,浓度分别为2.0%和0.5%,最佳无机盐为FeSO4。发酵48h后酶活较优化前的6.83U/mL提高到18.68U/mL,提高了1.73倍。

Phospholipase A1 is the single-minded enzyme which can hydrolyze natural phosphatide Sn-1 position acyl to get Sn-2 acyl lyso-phospholilid and fatty acid. The phospholipase may use in the trade in the refinery process （oil degum） to remove phospholipids. The strain named PL-06 which has high phospholipase A1 is obtained from the rich oil soil by using lecithin as the only carbon source and it＇s fermentation conditions of shake flask is optimized in this paper. The result showed that the best nitrogen source was NH4Cl and the best complex carbon source was the combination of malt sugar and lecithin, the density respectively is 2.0% and 0.5%, and the best salt is FeSO4. In such condition, the activity of phospholipase A1 of PL-06 can reach 18.68U/mL which is 1.73 times higher than that of the non- optimized condition（ 6.83U/mL ） after 48 hours fermentation.