Immobilization of chitosan-modified invertase on alginate-coated chitin support via polyelectrolyte complex formation

摘要

Saccharomyces cerevisiae invertase was chemically modified with chitosan and further immobilized on sodium alginate-coated chitin support.The yield of immobilized protein was determined as 85% and the enzyme retained 97% of the initial chitosan-invertase activity.The optimum temperature for invertase was increased by 10 deg C and its thermostability was enhanced by about 9 deg C after immobilization.The immobilized enzyme was stable against incubation in high ionic strength solutions and was four-fold more resistant to thermal treatment at 65 deg C than the native counterpart.The biocatalyst prepared retained 80% of the original catalytic activity after 50 h under continuous operational regime in a packed bed reactor.