Characteristics of yeast invertase immobilized on porous cellulose beads.


Journal Article

Invertase from Candida utilis was immobilized on porous cellulose beads by an ionic-quanidino bond. The immobilized invertase showed optimum activity between pH 4.0 and 5.4, while the free enzyme had a sharp optimum at pH 4.1. Both temperature profiles were fairly similar up to 55 degrees C. However, above this temperature the immobilized enzyme was more stable than the free enzyme. From the temperature data, the activation energies were found to be 7,322 and 4,052 cal/g mol for the free and the immobilized enzyme, respectively. Candida invertase shows characteristics of substrate inhibition. Both the Km and Ki for the free and the immobilized enzymes were determined. The apparent Ki for the immobilized invertase was much higher than the Ki of the free enzyme, suggesting a diffusion effect. Immobilized invertase molecules deep in the pores only see sucrose concentrations much less than the bulk concentrations. Immobilization, thus, offers certain processing advantages in this regard.

Full Text

Cited Authors

  • Dickensheets, PA; Chen, LF; Tsao, GT

Published Date

  • March 1, 1977

Published In

Volume / Issue

  • 19 / 3

Start / End Page

  • 365 - 375

PubMed ID

  • 14750

Pubmed Central ID

  • 14750

Electronic International Standard Serial Number (EISSN)

  • 1097-0290

International Standard Serial Number (ISSN)

  • 0006-3592

Digital Object Identifier (DOI)

  • 10.1002/bit.260190307


  • eng