抄録
Water insoluble tomato β-fructofuranosidase (β-FFase) was prepared by embedding it within a polyacrylamide gel and by adsorbing it on CM-cellulose. The activity of freezedried preparations of the embedded β-FFase retained only 25% of their original activity.
The β-FFase adsorbed on CM-cellulose was not released from the carrier at pH values below 5.0. The insolubilized β-FFase was not released by substrate from either carrier.
The optimal pH for embedded β-FFase using sucrose as the substrate was similar to that of the soluble enzyme.
The Km values of both embedded and adsorbed insoluble enzymes were calculated to be 1.4×10-3M and 6.9×10-3M, respectively.
There is a slight break with the embedded β-FFase in the Arrhenius plot at 21°C, but not with the β-FFase adsorbed on CM-cellulose. The activation energy of embedded β-FFase at a temperature range above and below the intersection was 15, 600 and 3, 200 cal/mole, respectively. The activation energy of the β-FFase adsorbed to CM-cellulose was 8, 300 cal/mole. The activity of polyacrylamide embedded β-FFase is considerably less inhibited by β-chloromercuribenzoate (pCMB) and silver ions than that of the CM-cellulose adsorbed enzyme.
