ABSTRACT
Alliinase is immobilized on pre-activated chitosan microspheres by glutaraldehyde.The optimum immobilization conditions are as follows: glutaraldehyde concentration is 4%,alliinase concentration 20.2U,immobilization time 2h.For immobilized alliinase,the highest activity was allowed at pH 7.0 and temperature 35℃,and the Michaelis constant(Km)was disclosed to be 7.9mmol/L by Lineweaver-Burk plot,and after 10 times reuses the immobilized alliinase lost no more than 10% activity.
ABSTRACT
A kinetics model was developed for predicting and simulating immobilized cellulase performance, which follows Michaelis-Menten kinetics with competitive product inhibition. Taking into account the effects of competitive product inhibition, inner diffusional limitation, substrate concentration and carrier size, the substrate distribution and the product distribution in carriers were investigated, and the effectiveness factors were also calculated over a wide range of parameters. The effects of competitive product inhibition are shown to increase the substrate concentration in the carrier, and, additionally, to increase the effectiveness factors slightly. With the increase of inner diffusion coefficient, both the effectiveness factors and the substrate concentration in the carrier increase. As the carrier size increases, on the other hand, these values decrease. The effectiveness factors and the substrate concentration in the carrier are found to increase when substrate concentration in the reaction system increases.