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高等学校化学研究 ›› 2003, Vol. 19 ›› Issue (3): 324-329.

• Articles • 上一篇    下一篇

Immobilization of Penicillin G Acylase on Calcined Layered Double Hydroxides

REN Ling-ling, HE Jing, Evans D. G., DUAN Xue   

  1. Key Laboratory of Science & Technology of Controllable Chemical Reactions, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, P. R. China
  • 收稿日期:2002-05-26 出版日期:2003-08-24 发布日期:2011-08-06
  • 基金资助:

    Supported by the National Natural Science Foundation of China(No.29973004).

Immobilization of Penicillin G Acylase on Calcined Layered Double Hydroxides

REN Ling-ling, HE Jing, Evans D. G., DUAN Xue   

  1. Key Laboratory of Science & Technology of Controllable Chemical Reactions, Ministry of Education, Beijing University of Chemical Technology, Beijing 100029, P. R. China
  • Received:2002-05-26 Online:2003-08-24 Published:2011-08-06
  • Supported by:

    Supported by the National Natural Science Foundation of China(No.29973004).

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摘要： A hydrotalcite-like Mg2+/Al3+ layered double hydroxide(LDH) material was prepared by means of a modified coprecipitation method involving a rapid mixing step followed by a separate aging process. LDH calcined at 500 ℃, denoted as CLDH, was characterized by XRD, IR and BET surface area measurements. CLDH has a poor crystalline MgO-like structure with a high surface area and porosity. CLDH was used as a support for the immobilization of penicillin G acylase(PGA). The effect of varying the immobilization conditions, such as pH, contact time and the ratio of enzyme to support, on the activity of the immobilized enzyme in the hydrolysis of penicillin G has been studied. It was found that the activity of the immobilized enzyme decreased slightly with decreasing pH and reached a maximum after a contact time of 24 h. The activity of the immobilized enzyme increased with increasing the ratio of enzyme to support. It was found that the adsorption of PGA inhibited the expected reaction of CLDH with an aqueous medium to regenerate a LDH phase. Its original activity(36%) after 15 cycles of reuse of the immobilized enzyme was retained, but no further loss in the activity was observed.

关键词: Immobilized enzyme, Penicillin G acylase, Layered double hydroxide, Calcination

Abstract: A hydrotalcite-like Mg2+/Al3+ layered double hydroxide(LDH) material was prepared by means of a modified coprecipitation method involving a rapid mixing step followed by a separate aging process. LDH calcined at 500 ℃, denoted as CLDH, was characterized by XRD, IR and BET surface area measurements. CLDH has a poor crystalline MgO-like structure with a high surface area and porosity. CLDH was used as a support for the immobilization of penicillin G acylase(PGA). The effect of varying the immobilization conditions, such as pH, contact time and the ratio of enzyme to support, on the activity of the immobilized enzyme in the hydrolysis of penicillin G has been studied. It was found that the activity of the immobilized enzyme decreased slightly with decreasing pH and reached a maximum after a contact time of 24 h. The activity of the immobilized enzyme increased with increasing the ratio of enzyme to support. It was found that the adsorption of PGA inhibited the expected reaction of CLDH with an aqueous medium to regenerate a LDH phase. Its original activity(36%) after 15 cycles of reuse of the immobilized enzyme was retained, but no further loss in the activity was observed.

Key words: Immobilized enzyme, Penicillin G acylase, Layered double hydroxide, Calcination