BATCH CULTURE THERMO TOLERANCE OF SACCHAROMYCES CEREVISIAE DURING INVERTASE PRODUCTION

Abstract

Saccharomyces cerevisiae strains IIB-12 (wild) and NG-46 (mutant) were compared
on the basis of kinetics and thermo tolerance for invertase production. NG-46
showed significantly higher (p0.05) values of Qp and Yp/s compared to other yeast
strains. Thermodynamics revealed that cell system exerted protection against thermal
inactivation during product formation. The enthalpy (H, KJ/mol) and entropy of
activation (S, J/mol/K) for Invertase production substantially improved specificity
constant activation energy, free energies for transition state formation and substrate
binding for sucrose fermenting. The results highlighted an improvement in thermo
stability (>40°C) of microbial endogenous metabolism for enzyme secretion