Repeated Enzymatic Hydrolysis of Polygalacturonic Acid, Chitosan and Chitin Using a Novel Reversibly-soluble Pectinase with the Aid of κ-carrageenan

Aspergillus niger pectinase, together with κ-carrageenan, could be precipitated in the presence of 0.2% KCl and re-dissolved by ten-fold dilution of the salt. The free as well as this reversibly-soluble (rs) enzyme were evaluated for hydrolysis of polygalacturonic acid, chitosan and chitin. The rs-enzyme showed 92%, 80% and 74% activity (as compared to the corresponding amount of enzyme when present as a free enzyme) towards the three substrates, respectively. There was no significant change in the pH and temperature optima of the rs-enzyme. This preparation could be reused six times without loss of any detectable polygalacturonase activity. This biocatalyst design was found to be efficient for the hydrolysis of polygalacturonic acid, chitosan and chitin.