Abstract：
The lipase from Prunus dulcis almonds was inactivated under different conditions. At pH 5 and 9, enzyme stability remained similar under the different studied buffers. However, when the inactivation was performed at pH 7, there were some clear differences on enzyme stability depending on the buffer used. The enzyme was more stable in Gly than when Tris was employed for inactivation. Then, the enzyme was immobilized on methacrylate beads coated with octadecyl groups at pH 7 in the presence of Gly, Tris, phosphate and HEPES. Its activity was assayed versus triacetin and S-methyl mandelate. The biocatalyst prepared in phosphate was more active versus S-methyl mandelate, while the other ones were more active versus triacetin. The immobilized enzyme stability at pH 7 depends on the buffer used for enzyme immobilization. The buffer used in the inactivation and the substrate used determined the activity. For example, glycine was the buffer that promoted the lowest or the highest stabilities depending on the substrate used to quantify the activities.
摘要：
在不同条件下，李子杏仁的脂肪酶被灭活。在pH5和9时,酶稳定性在不同研究的缓冲液下保持相似。然而,当在pH7下进行失活时,取决于所使用的缓冲液,酶稳定性存在一些明显差异。该酶在Gly中比使用Tris灭活时更稳定。然后，在pH7下，在Gly存在下，将酶固定在涂有十八烷基的甲基丙烯酸酯珠上，Tris,磷酸盐和HEPES。相对于三醋精和S-甲基扁桃酸盐测定其活性。在磷酸盐中制备的生物催化剂比S-甲基扁桃酸酯活性更高，而其他的比三醋精更活跃。在pH7下的固定化酶稳定性取决于用于酶固定化的缓冲液。在失活中使用的缓冲液和使用的底物确定活性。例如,甘氨酸是促进最低或最高稳定性的缓冲液，这取决于用于定量活性的底物。
