| Six kinds of polystyrene microspheres with different pore sizes and hydrophobicities were used to immobilize lipase YS2071 by adsorption, and the optimal carrier was obtained. The immobilization conditions were optimized and the properties of immobilized lipase were studied. The results showed that the amino polystyrene microspheres B with particle size in the range of 0.6-1 μm had the best immobilization effect. Under the conditions of enzyme mass concentration 5 mg/mL, pH 10, immobilization temperature 20?℃, rotational speed 250 r/min and adsorption time 6 h, the enzyme recovery was up to 4282%. Compared with YS2071 lipase free enzyme, the immobilized lipase had better temperature stability, metal ion stability, organic solvent stability and pH stability. After 30 d storage at 25?℃, the retention rate of immobilized enzyme activity was 15.09 percentage points higher than that of free enzyme. Being reused for five times, the enzyme activity retention rate of immobilized enzyme was 63.77%. |
