Polyelectrolyte complex formation mediated immobilization of chitosan-invertase neoglycoconjugate on pectin-coated chitin

摘要

Saccharomyces cerevisiae invertase, chemically modified with chitosan, was immobilized on pectincoated chitin support via polyelectrolyte complex formation. The yield of immobilized enzyme protein was determined as 85% and the immobilized biocatalyst retained 97% of the initial chitosan-invertase activity. The optimum temperature for invertase was increased by 10℃ and its thermostability was enhanced by about 10℃ after immobilization. The immobilized enzyme was stable against incubation in high ionic strength solutions and was 4-fold more resistant to thermal treatment at 65℃ than the native counterpart. The biocatalyst prepared retained 96 and 95% of the original catalytic activity after ten cycles of reuse and 74 h of continuous operational regime in a packed bed reactor, respectively.