Bdiri Myriam, Bensghaier Asma, Chaabane Lobna, Kozmai Anton, Baklouti Lassaad, Larchet Christian
Institut de Chimie et des Matériaux Paris-Est (ICMPE), Université Paris-Est, UMR 7182 CNRS, 2 Rue Henri Dunant, 94320 Thiais, France.
Membrane Institute, Kuban State University, 149 Stavropolskaya Street, 350040 Krasnodar, Russia.
Membranes (Basel). 2019 Sep 3;9(9):114. doi: 10.3390/membranes9090114.
The use of enzymatic agents as biological solutions for cleaning ion-exchange membranes fouled by organic compounds during electrodialysis (ED) treatments in the food industry could be an interesting alternative to chemical cleanings implemented at an industrial scale. This paper is focused on testing the cleaning efficiency of three enzyme classes (β-glucanase, protease, and polyphenol oxidase) chosen for their specific actions on polysaccharides, proteins, and phenolic compounds, respectively, fouled on a homogeneous cation-exchange membrane (referred CMX-Sb) used for tartaric stabilization of red wine by ED in industry. First, enzymatic cleaning tests were performed using each enzyme solution separately with two different concentrations (0.1 and 1.0 g/L) at different incubation temperatures (30, 35, 40, 45, and 50 °C). The evolution of membrane parameters (electrical conductivity, ion-exchange capacity, and contact angle) was determined to estimate the efficiency of the membrane's principal action as well as its side activities. Based on these tests, we determined the optimal operating conditions for optimal recovery of the studied characteristics. Then, cleaning with three successive enzyme solutions or the use of two enzymes simultaneously in an enzyme mixture were tested taking into account the optimal conditions of their enzymatic activity (concentration, temperatures, and pH). This study led to significant results, indicating effective external and internal cleaning by the studied enzymes (a recovery of at least 25% of the electrical conductivity, 14% of the ion-exchange capacity, and 12% of the contact angle), and demonstrated the presence of possible enzyme combinations for the enhancement of the global cleaning efficiency or reducing cleaning durations. These results prove, for the first time, the applicability of enzymatic cleanings to membranes, the inertia of their action towards polymer matrix to the extent that the choice of enzymes is specific to the fouling substrates.
在食品工业的电渗析（ED）处理过程中，使用酶制剂作为生物解决方案来清洁被有机化合物污染的离子交换膜，可能是工业规模化学清洗的一个有趣替代方案。本文重点测试了三种酶（β-葡聚糖酶、蛋白酶和多酚氧化酶）的清洗效率，这三种酶分别对工业上用于通过电渗析进行红酒酒石稳定化处理的均质阳离子交换膜（简称CMX-Sb）上污染的多糖、蛋白质和酚类化合物具有特定作用。首先，分别使用两种不同浓度（0.1和1.0 g/L）的每种酶溶液在不同孵育温度（30、35、40、45和50°C）下进行酶清洗测试。测定膜参数（电导率、离子交换容量和接触角）的变化，以评估膜的主要作用效率及其副活性。基于这些测试，我们确定了使所研究特性实现最佳恢复的最佳操作条件。然后，考虑到酶活性的最佳条件（浓度、温度和pH），测试了用三种连续的酶溶液进行清洗或在酶混合物中同时使用两种酶的情况。这项研究取得了显著成果，表明所研究的酶能有效进行外部和内部清洗（电导率至少恢复25%、离子交换容量恢复14%、接触角恢复12%），并证明存在可能的酶组合可提高整体清洗效率或缩短清洗时间。这些结果首次证明了酶清洗对膜的适用性，以及在选择酶针对特定污染底物的情况下，其作用对聚合物基质的惰性。
