【摘要】 以活性白土、滑石粉为载体采用吸附法固定化大豆脂肪氧合酶(LOX)的优化条件为:(1)酶液对活性白土的用量比为897U/mg,在浓度为0 05mol/L、pH=7 0的磷酸盐缓冲液中20℃搅拌吸附30min;(2)酶液对滑石粉的用量比为238U/mg,在浓度为0 05mol/L、pH=8 0的磷酸盐缓冲液中10℃搅拌吸附15min。经放大后实验重复性良好。上述固定化酶置于0～4℃保存20d,酶活损失分别为19 2%和17 7%;与游离酶相比,能加快酶促反应的速度并使产率分别提高9 6%和42 5%。以海藻酸钠为载体采用包埋法得到的固定化酶珠的耐热、耐酸碱、耐有机溶剂能力较游离酶有很大提高,在φ(甘油)=75%的水溶液中保存33d,酶活基本保持不变;在50℃热处理60min后酶活仍能保持90%。更多还原

【Abstract】 The immobilization procedures of soybean lipoxygenase(LOX) using atlapulgite or talc as carrier are optimized and scaled up with a ratio of 897 U/mg atlapulgite stirring 30 min in a 0.05 mol/L and pH 7.0 phosphate buffer solution at 20 ℃,and a ratio of 238 U/mg talc stirring 15 min in a 0.05 mol/L and pH 8.0 phosphate buffer solution at 10 ℃.When kept at 0～4 ℃ for 20 days the immobilized enzyme loses activity by 19.2% for atlapulgite or 17.7% for talc.The immobilized enzyme leads a 9.6% higher yield for atlapulgite or 42.5% higher yield for talc in enzymatic reaction than the free LOX.The immobilized LOX beads using sodium alginate as carrier are much more stable than the free one when kept at a higher temperature,in broader pH range and in organic solvents.After being kept in glycerol〔φ(glycerol)=75%〕 for 33 days,the beads barely lose activity.The beads still maintain 90% activity at 50 ℃ for 60 min.更多还原