采用氯化锂诱变黑曲霉原生质体,筛选高产植酸酶菌株。获得制备黑曲霉原生质体的最适条件:纤维素酶1.0%,蜗牛酶0.5%,菌龄24 h,酶解温度30℃,酶解时间2 h,渗透压稳定剂0.7 mol/L NaCl。采用氯化锂对制得的原生质体进行诱变,结果表明:经0.15%LiCl诱变后,原生质体存活率为23.37%,此时,获得一株植酸酶活最高的突变株,为19.24 U/mL,比出发菌株提高54.41%,该菌株具有良好的遗传稳定性。

Lithium chloride was used to induce protoplasts of Aspergillus niger.Mutation strain with higher phytase content was screened in this paper.The optimized isolation method for protoplasts from Aspergillus niger was obtained.The results showed that the suitable conditions were cellulose 1%,snailase 0.5%,mycelium age 24h,enzymatic hydrolysis temperature 30℃,time 2h and osmotic pressure stabilizer 0.7 mol/L sodium chloride.Lithium chloride was used to induce the protoplasts.The results showed that the survival rate of strains was 23.3% induced with 0.15% Lithium chloride.And one strain with the highest enzyme activity of 19.24 U/mL was obtained,and the enzyme activity has a 54.41% increase compared with the original strain.Heredity of induced strains was stable.