STUDIES ON THE PREPARATION AND CHARACTERIZATION OF IMMOBILIZED PAPAIN

Papain was immobilized on porous silica beads,chitosan and cellulose by cross linking with glutaraldehyde.Thermal activation of immobilized papain on porous silica beads has been first found and reported by us.In this article,the factors related with the activity of the immobilized papain on chitosan and cellulose,such as pH of the immobilized reaction,concentration of glutaraldehyde and amount of papain were studied.We also studied the characters of these immobilized papain,comparing with native papain and immobilized papain on porous silica beads.Thermal stability and durability on heating were emphasized.Their optimum reaction temperature were 80℃.After incubation at 90℃ for 1h,the activity of these immobilized papain was retained above 95%.After incubation at 70℃ for 5h or 6h,the activity of immobilized papain was also retained above 90%.These results showed that thermal stability and durability on heating of immobilized papain on chitosan and cellulose were improved considerably.