Determination of enzymatic activities of commercial pectinases for the clarification of apple juice
Determination of enzymatic activities of commercial pectinases for the clarification of apple juice
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DOI：
10.1016/s0308-8146(97)00088-5
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发表时间：
1998-01-01
期刊：
影响因子：
8.8
通讯作者：
Lozano, J
中科院分区：
文献类型：
--
作者：
Ceci, L;Lozano, J
采用不同的方法测试多聚半乳糖醛酸酶（PG）、果胶酯酶（PE）和果胶裂解酶（PL）活性，以苹果果胶为底物，对Rohapect DSS（RHD 5）和果胶醇（派）商业酶制剂进行测试。粘度法测定PG活性效果令人满意，但外源蛋白质会影响酶制剂溶液中PL活性的分光光度测定。虽然50摄氏度是一个明确的临界点，酶迅速降低其活性，热灭活的速度和范围是不同的，这取决于活性测定。PG活性表现出两个不同的热不稳定性时期，而PL则表现为双相性，对热高度敏感。还研究了果胶酶活性在3-7范围内的pH依赖性。(C)1998爱思唯尔科技有限公司。保留所有权利。
Different methods for testing Polygalacturonase (PG), pectinesterase (PE), and pectinlyase (PL) activities were applied to Rohapect DSS (RHD5) and Pectinol (PAI) commercial enzyme preparations in an apple pectin substrate. The viscometric method for PG activity determination was satisfactory, but foreign proteins could affect the spectrophotometric determination of PL activity in solutions of enzyme preparations. Although 50 degrees C was a well-defined breaking point where enzymes rapidly decrease their activity, rate and range of heat-inactivation were different depending on the activity assayed. While PG activity showed two periods of different thermolability, PL was monophasic and highly sensitive to heat. The pH dependence of the pectic enzyme activities was also studied over the 3-7 range. (C) 1998 Elsevier Science Ltd. All rights reserved.