高产胞外植酸酶酵母菌的选育

Screening Yeast Strain Producing High Extracellular Phytase

从酒糟样品中筛选得到 5株胞外植酸酶活性较高的野生型酵母菌 ,其中 1 1酵母的酶活性最高 ,胞外植酸酶活为 16 .6 8U /mL .1 1菌株经单倍体分离 ,得到单倍体Sp1 1,胞外植酸梅活为 11.2 0U/mL .以Sp1 1为出发菌株 ,经过原生质体紫外诱变和EMS诱变 ,选育得到一稳定突变体Msp 382 6 ,胞外植酸酶活性为 2 6 .6 5U /mL ,较出发菌株提高了 138%.

Yeasts producing extracellular phytase were obtained from samples of distiller s grains, and the best one was strain 1-1, with extracellular phytase activity 16.68U/mL. The haploid Sp1-1 isolated from the strain 1-1, was used as the original strain. A high-producing mutant strain, named Msp-3826, was obtained through breeding by UV and EMS. The extracellular phytase activity of Msp-3826 was about 26.65U/mL, increased by 138% compared with the original strain, and was very stable.