摘要：

As a novel support of immobilizing penicillin G acylase (PGA),MCM-48 and Co-MCM-48 molecular sieves were synthesized and characterized by XRD,N_2 adsorption,NH_3-TPD,FT-IR and so on.The studies show that MCM-48 and Co-MCM-48 has well ordered long-range structure,narrow pore size distribution,larger surface area and higher concentration of the weakly acidic silanol groups on their surface.Penicillin G acylase was immobilized on MCM-48 or Co-MCM-48 by interacting silanol groups on the surface.The presence of cobalt in the framework of MCM-48 increases the amount of the weak acid sites.For the hydrolysis of penicillin G catalyzed by PGA/Co-MCM-48 (Co/Si=0.01),its specific activity reaches 1682U/g.After used for six cycles,PGA/MCM-48(0.01) can keep 1375U/g of the specific activity.If MCM-41 was used as the support,the activity of immobilized PGA is only 402 U/g.

展开