Studi sull'utilizzo delle bucce di soia e dei loro estratti sul trattamento di inquinanti nelle acque

Global pollution caused by population growth and highly industrial activity increases the interest in finding more efficient technologies for the treatment of wastes. In recent years, new methods more biocompatible than the classical chemical strategies are developing. A new and promising remediation approach in the wastewater treatment is the use of enzymes, because their ability to performing specific reactions at elevated rates, not reachable by traditional chemical or physical catalysis, and in mild conditions. The enzymatic method to remove pollutant compounds from aqueous solution was firstly proposed by Klibanov and Morris in the treatment of industrial aqueous effluents containing carcinogenic aromatic amines by horseradish peroxidase (HRP) and hydrogen peroxide. The main drawback in using HRP is its unavailability in large quantity at a price appropriate for wastes treatment. In contrast, the soybean peroxidase (SBP) is present in high amount in the soybean seed hulls that are a by-product of soybean manufacturing process. Moreover, this protein has attracted considerable biotechnological attention due to its high stability and activity. This thesis is focused on the extraction of soybean peroxidase from the hulls and the evaluation of its application in the pentachlorophenol (PCP) degradation both by using the SBP in solution and immobilized on silica monoliths. On the other hand, preliminary studied with SBP extracted from hulls of different soybean varieties were also conducted. Moreover, soybean hulls after SBP extraction were used as adsorbent of metals ions and organic dyes in order to verify the possible uses of these by-products as final step of their industrial cycle. The possible release of the adsorbates from the hulls was also analysed with different desorption treatments. In the last part of this thesis, a preliminary study on three different perovskites was conducted with the aim to evaluate the production of hydrogen peroxide of these materials for a future application in combination with the soybean peroxidase.