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Covalent Assembly of Penicillin Acylase in Mesoporous Silica Based on Macromolecular Crowding Theory 被引量:11
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作者 王安明 周成 +3 位作者 王华 沈树宝 薛建跃 欧阳平凯 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期788-790,共3页
To improve the covalent immobilization of penicillin acylase (PA), macromolecular crowding theory was applied to its immobilization. Influence of mass ratio of enzyme to the silica, as well as, activation time with ... To improve the covalent immobilization of penicillin acylase (PA), macromolecular crowding theory was applied to its immobilization. Influence of mass ratio of enzyme to the silica, as well as, activation time with glutaraldehyde on the activity of assembled PA, was studied. In the mesopores, the effect of fl-cyclodextrin (β-CD) on the immobilization of the enzyme was also investigated. It was remarkable that the coupled yield and relative activity reached 99.5% and 92.3%, respectively, when penicillin acylase assembled covalently in the mesopores. The results here indicate that mimicked macromolecule crowding could significantly ameliorate the performance of covalently immobilized PA. 展开更多
关键词 enzyme immobilization penicillin acylase Β-CYCLODEXTRIN macromolecule crowding
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An efficient synthesis of ampicillin on magnetically separable immobilized penicillin G acylase 被引量:6
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作者 Ping Xue Xiao Dan Song Xue Rong Cao 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第7期765-768,共4页
Penicillin G acylase(PGA) was immobilized on the magnetic hydrophilic polymer microspheres with average pore size of 17.1 nm,specific surface area of 128.2 m2/g and saturate magnetization of 6.4 emu/g.The 96.7%ampicil... Penicillin G acylase(PGA) was immobilized on the magnetic hydrophilic polymer microspheres with average pore size of 17.1 nm,specific surface area of 128.2 m2/g and saturate magnetization of 6.4 emu/g.The 96.7%ampicillin yield with 1.60 of the synthesis/hydrolysis(S/H) ratio from 6-aminopenicillanic acid(6-APA) and D-(-)-alpha-phenylglycine methyl ester(D-PGME) can be achieved using the resultant magnetic biocatalyst in ethylene glycol,where only 82.1%yield with 1.40 of the S/H ratio was obtained using the free PGA under the identical reaction conditions.The immobilized PGA can be separated magnetically and recycled for five times without obvious loss of its catalytic activity. 展开更多
关键词 Immobilized penicillin G acylase Magnetic polymer microspheres Ampicillin synthesis REUSABILITY
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Immobilization of penicillin G acylase on paramagnetic polymer microspheres with epoxy groups 被引量:7
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作者 Xing Chen Lu Yang +5 位作者 Wangcheng Zhan Li Wang Yun Guo Yunsong Wang Guanzhong Lu Yanglong Guo 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2018年第1期47-53,共7页
Paramagnetic polymer microspheres were synthesized by the inverse suspension polymerizationmethod through polymerization of glycidyl methacrylate,ally glycidyl ether and methacrylamide onthe surface of silica‐coated ... Paramagnetic polymer microspheres were synthesized by the inverse suspension polymerizationmethod through polymerization of glycidyl methacrylate,ally glycidyl ether and methacrylamide onthe surface of silica‐coated Fe3O4nanoparticles using N,N’‐methylene‐bis(acrylamide)as across‐linking agent.Penicillin G acylase(PGA)was covalently immobilized on the surface of theparamagnetic microspheres by reacting the amino groups of the PGA molecules with the epoxygroups of the paramagnetic polymer microspheres.The effect of the SiO2coating and the amount ofparamagnetic Fe3O4nanoparticles on the initial activity and the operational stability of the immobilizedPGA was investigated.The results indicated that SiO2played an important role in the polymerization process and paramagnetic polymer microspheres with a SiO2‐coated Fe3O4nanoparticles mass content of7.5%are an optimal support material for PGA immobilization.Immobilized PGA on the paramagnetic polymer microspheres shows a high initial activity of430U/g(wet)and retains99%of its initial activity after recycling10times.Furthermore,immobilized PGA exhibits high thermal stability,pH stability and excellent reusability,which can be rapidly recycled by the aid of magnet.?2018,Dalian Institute of Chemical Physics,Chinese Academy of Sciences.Published by Elsevier B.V.All rights reserved. 展开更多
关键词 Paramagnetic polymer microspheres Epoxy groups penicillin G acylase Covalent bonding IMMOBILIZATION
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Poly(GMA/MA/MBAA)Copolymer Beads:a Highly Efficient Support Immobilizing Penicillin G Acylase 被引量:3
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作者 Ping XUE Guan Zhong LU Wan Yi LIU 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第1期129-132,共4页
The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate (GMA)/methacrylamide(MA)/N,N'-methylene-bis(acrylamide)(MBAA)was synthesized using the industrial agents by inverse suspensio... The hydrophilic, macroporous and beaded ternary copolymer of glycidyl methacrylate (GMA)/methacrylamide(MA)/N,N'-methylene-bis(acrylamide)(MBAA)was synthesized using the industrial agents by inverse suspension polymerization. The apparent activity of the immobilized penicillin G acylase reached 1096 IU/g for hydrolysis penicillin G on the beads with diameter of 0.11-0.13 ram, and it changed hardly after 50 cycles. It can be expected to be a good potential in industrial application, 展开更多
关键词 Poly(GMA/MA/MBAA) copolymer beads penicillin G acylase immobilization inverse suspension polymerization.
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Immobilization of Penicillin G Acylase on Magnetic Nanoparticles Modified by Ionic Liquids 被引量:2
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作者 周华从 李伟 +4 位作者 寿庆辉 高红帅 徐芃 邓伏礼 刘会洲 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2012年第1期146-151,共6页
Functionalized ionic liquids containing ethyoxyl groups were synthesized and immobilized on magnetic silica nanoparticles (MSNP) prepared by two steps, i.e., Fe304 synthesis and silica shell growth on the surface. T... Functionalized ionic liquids containing ethyoxyl groups were synthesized and immobilized on magnetic silica nanoparticles (MSNP) prepared by two steps, i.e., Fe304 synthesis and silica shell growth on the surface. This magnetic nanoparticle supported ionic liquid (MNP-IL) were applied in the immobilization of penicillin G acylase (PGA). The MSNPs and MNP-ILs were characterized by themeans of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and vibrating sample magnetometer (VSM). The results showed that the average size of magnetic Fe304 nanoparticles and MSNPs were -10 and -90 nm, respectively. The saturation magnetizations of magnetic Fe304 nanoparticles and MNP-ILs were 63.7 and 26.9 A'm2·kg^-1, respectively. The MNP-IL was successfully applied in the immobilization of PGA. The maximum amount of loaded enzyme-was about 209 mg·g^-1 (based on carder), and the highest enzyme activity of immobilized PGA (based on ImPGA) was 261 U·g^-1. Both the amount of loaded enzyme and the activity of ImPGA are at the same leyel of or higher than that in previous reports. After 10 consecutive operat!ons, ImPGA still mainrained 62% of its initial activity, indicating the'good recovery property of ImPGA activity. The ionic liquid modified magnetic particles integrate the magnetic properties of Fe304 and the structure-tunable properties of ionic liquids, and have extensive potential uses in protein immobilization and magnetic bioseparation. This work may open up a novel strategy to immobilize proteins by ionic liquids. 展开更多
关键词 magnetic iron oxide magnetic nanoparticles ionic liquids penicillin G acylase enzyme immobilization
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Immobilization of Penicillin G Acylase on Calcined Layered Double Hydroxides
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作者 Evans D.G. 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第3期324-329,共6页
A hydrotalcite-like Mg 2+ /Al 3+ 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 calci... A hydrotalcite-like Mg 2+ /Al 3+ 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. 展开更多
关键词 Immobilized enzyme penicillin G acylase Layered double hydroxide CALCINATION
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Gold Nanoparticles for Colorimetric detection of hydrolysis of antibiotics by penicillin G acylase
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作者 Neha R. Tiwari Ambrish Rathore +1 位作者 Asmita Prabhune Sulabha K. Kulkarni 《Advances in Bioscience and Biotechnology》 2010年第4期322-329,共8页
A simple inexpensive method of monitoring hydrolysis of an antibiotic penicillin G (pen G) and subsequent enzyme detection using gold nanoparticles is presented. Gold nanoparticles capped with Cetyl trimethyl ammonium... A simple inexpensive method of monitoring hydrolysis of an antibiotic penicillin G (pen G) and subsequent enzyme detection using gold nanoparticles is presented. Gold nanoparticles capped with Cetyl trimethyl ammonium bromide (CTAB) are synthesized using chemical route. The particles could be used for detection of Penicillin G acylase (PGA) enzyme by incorporating hydrolysis reaction with pen G. This hydrolysis reaction leads to a shift in the surface plasmon band of gold nanoparticles from 527 nm to 545 nm accompanied by a visual colorimetric change in the solution from red to blue. The process is attributed to aggregation of nanoparticles caused due to displacement of CTAB bilayer by byproducts of the hydrolysis reaction. It is proposed that the presence of 0.007 mg/ml of PGA can be detected by a color change of gold nanoparticles solution without requiring any complicated instrument or highly trained operator to conduct the test. The method could also identify the presence of different penicillins by showing different spectral shifts. Thus the work presented here would be useful not only for the detection of the pharmaceutically important drug Pen G, but also represents a general methodology for the detection of enzymes, eg PGA. 展开更多
关键词 Gold Nanoparticles penicillin G acylase Aggregation COLORIMETRIC Detection Surface PLASMON Resonance
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优化动态核主元分析的工业过程故障监测方法
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作者 杨芳 王亚君 沈亚慧 《实验室研究与探索》 CAS 北大核心 2024年第1期6-10,19,共6页
针对现代生产工业过程中数据的非线性多模态特征,提出了一种基于人工大猩猩部队优化动态核主元分析(GTO-DKPCA)的故障监测方法。利用自回归移动平均时间序列模型和核主成分分析(KPCA)方法构建DKPCA模型,对过程各阶段的批次数据进行DKPC... 针对现代生产工业过程中数据的非线性多模态特征,提出了一种基于人工大猩猩部队优化动态核主元分析(GTO-DKPCA)的故障监测方法。利用自回归移动平均时间序列模型和核主成分分析(KPCA)方法构建DKPCA模型,对过程各阶段的批次数据进行DKPCA处理。通过正常数据和故障数据特征构建自适应度函数,利用人工大猩猩部队优化算法对DKPCA核参数进行优化,以发现最优的非线性特征;通过计算各时间点的霍特林统计量T2和平方预测误差(SPE)统计量进行故障监测。青霉素发酵过程故障监测结果表明,GTO-DKPCA方法比多向核主元分析(MKPCA)和多动态核主元分析(BDKPCA)有更好的监测效果,适应性和准确性更高。 展开更多
关键词 动态核主元分析 人工大猩猩部队优化算法 故障监测 青霉素发酵
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头孢洛林酯合成工艺改进
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作者 孔瑜 蒋宪龙 +1 位作者 焦翠玲 刘彩锋 《山东化工》 CAS 2024年第15期85-87,91,共4页
以GHYH为起始物料,GHYH与苯磺酰氯制备磺酸酯,与PTT发生取代反应;甲基苯磺酸甲酯作为甲基化试剂,用甲酚和固定化青霉素酶分别脱掉羧基和氨基保护基,然后与ATDE-Cl反应,在醋酸和水的混合溶液中重结晶得到头孢洛林酯;这种合成方法比较适... 以GHYH为起始物料,GHYH与苯磺酰氯制备磺酸酯,与PTT发生取代反应;甲基苯磺酸甲酯作为甲基化试剂,用甲酚和固定化青霉素酶分别脱掉羧基和氨基保护基,然后与ATDE-Cl反应,在醋酸和水的混合溶液中重结晶得到头孢洛林酯;这种合成方法比较适用于工业化生产,甲酰氯在改进后的合成路线中不使用,操作简单,不产生含磷废水,产生较少杂质,原料便宜,质量提高,对环境的污染也较小。 展开更多
关键词 GHYH 抗生素 头孢洛林酯 苯磺酰氯 青霉素酰化酶
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青霉素酰化酶的发酵工艺与提取工艺
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作者 王惠 《化工管理》 2023年第10期159-161,共3页
青霉素是一种在临床上得到广泛应用的抗生素,具有良好的临床疗效,但同时也有过敏反应、多药等不良反应,使其在临床上的应用受到极大的制约。青霉素酰化酶是一种具有抗菌、抗肿瘤活性的生物催化活性。因此,文章阐述了发酵法提取青霉素酰... 青霉素是一种在临床上得到广泛应用的抗生素,具有良好的临床疗效,但同时也有过敏反应、多药等不良反应,使其在临床上的应用受到极大的制约。青霉素酰化酶是一种具有抗菌、抗肿瘤活性的生物催化活性。因此,文章阐述了发酵法提取青霉素酰化酶研究的重要意义,介绍了青霉素酰化酶的发酵工艺与提取工艺。 展开更多
关键词 青霉素酰化酶 发酵工艺 提取工艺
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含环氧基亲水性固定化青霉素酰化酶共聚载体的合成与性能研究 被引量:19
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作者 薛屏 卢冠忠 +1 位作者 郭杨龙 王筠松 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2004年第2期361-365,共5页
环氧基团可以在温和条件下与酶分子的氨基反应使其固定于载体表面 .选用含有活性环氧基团的甲基丙烯酸缩水甘油酯 ( GMA)和亲水性的 N -乙烯吡咯烷酮 ( NVP)两种单体 ,以 N ,N′-亚甲基双丙烯酰胺( MBAA)为交联剂 ,甲醇水溶液作致孔剂 ... 环氧基团可以在温和条件下与酶分子的氨基反应使其固定于载体表面 .选用含有活性环氧基团的甲基丙烯酸缩水甘油酯 ( GMA)和亲水性的 N -乙烯吡咯烷酮 ( NVP)两种单体 ,以 N ,N′-亚甲基双丙烯酰胺( MBAA)为交联剂 ,甲醇水溶液作致孔剂 ,液体石蜡为主介质 ,通过反相悬浮聚合技术成功地合成了亲水性大孔 GMA-NVP-MBAA三元共聚物载体 ( GNM) .通过调节交联剂的用量和单体 NVP与 GMA的比例 ,可以调节载体的孔径、比表面积及在水中的溶胀性能 .将巨大芽孢杆菌青霉素酰化酶共价偶联于平均孔径为1 6.5 nm、表面环氧基含量为 0 .90 6mmol/g的 GNM共聚物载体 ,制成固定化酰化酶 ,其表观活性高达 62 5U/g,水解青霉素 G钾盐的最适宜温度为 5 0℃ ,p H值为 8.0 .固定化酶在 4℃保存 40 d,活性保持不变 .经3次使用后 ,活性达到稳定值 ( 60 1 U /g左右 ) ,再经 1 2次使用 。 展开更多
关键词 环氧基团 亲水性载体 固定化青霉素酰化酶 合成 反相悬浮聚合 半合成抗生素 结构 性能
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高分子载体材料对青霉素酰化酶的固定化作用 被引量:9
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作者 薛屏 卢冠忠 +1 位作者 郭杨龙 王筠松 《功能高分子学报》 CAS CSCD 北大核心 2005年第2期340-346,共7页
介绍了天然高分子材料和合成高分子材料对青霉素酰化酶的固定化作用,着重讨论了高分子材料的制备、性质及其表面修饰对固定化酶活性和使用稳定性的影响。
关键词 青霉素 酰化酶 高分子载体材料 固定化作用 制备方法 表面修饰 活性 稳定性 固定化酶
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不同介孔材料固定青霉素酰化酶的稳定性研究 被引量:21
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作者 高波 朱广山 +4 位作者 付学奇 辛明红 陈静 王春雷 裘式纶 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2005年第10期1852-1854,共3页
Silica mesoporous materials were synthesized and used as the supporting materials for immobilization of enzyme.Penicillin G acylase,an enzyme which was used to produce 6-APA in pharmaceutical industry,was immobilized ... Silica mesoporous materials were synthesized and used as the supporting materials for immobilization of enzyme.Penicillin G acylase,an enzyme which was used to produce 6-APA in pharmaceutical industry,was immobilized in the mesoporous materials by the immersion method.The stabilities of the immobilized penicillin G acylase were studied.After incubation at 60 ℃ for 2 h,the activity of immobilized penicillin G acylase remained 80% in the best case.At higher or lower pH,the free enzyme was deactivated quickly,while the immobilized enzyme still retained active.The result of operational stability showed that the immobilized(enzyme) retained 70% of its initial activity after operating for 6 times.These results showed that the stabilities of immobilized penicillin G acylase,related to the pore size of mesoporous materials,were increased significantly compared with those of free enzyme.The improvement of stabilities of immobilized enzyme was significant when the pore size of the mesoporous materials matched the enzyme molecule size. 展开更多
关键词 介孔材料 固定化酶 青霉素酰化酶 稳定性
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反胶束体系中青霉素酰化酶活性及稳定性研究 被引量:10
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作者 王普 陈希杨 +1 位作者 应国清 杨根生 《高校化学工程学报》 EI CAS CSCD 北大核心 2002年第4期426-429,共4页
反胶束体系是一种新型的酶反应介质体系。构建合适的反应体系,使青霉素酰化酶在该体系中保持较高的酶活性,是实现反胶束体系中酶法合成头孢类抗生素的关键所在。本文分别考察了青霉素酰化酶在CTAB/正己醇和CTAB/异辛烷/正己醇两种反胶... 反胶束体系是一种新型的酶反应介质体系。构建合适的反应体系,使青霉素酰化酶在该体系中保持较高的酶活性,是实现反胶束体系中酶法合成头孢类抗生素的关键所在。本文分别考察了青霉素酰化酶在CTAB/正己醇和CTAB/异辛烷/正己醇两种反胶束体系中不同水含量和pH值对酶活力的影响。结果表明:包埋于CTAB/异辛烷/正己醇反胶束体系中的青霉素酰化酶在W0为14、pH为7.2时表现出较高的酶活性。试验中还考察了不同温度对包埋于CTAB/异辛烷/正己醇反胶束体系中的青霉素酰化酶活力的影响,并与游离酶液进行了比较。该酶在所采用的反胶束体系中的最适水解反应温度为39℃,较游离酶液的最适水解温度升高了2℃。同时酶的热稳定性亦较游离酶液有所提高,表现在CTAB/异辛烷/正己醇反胶束体系中,经50℃保温240 min,酶活保留率为76.0%, 而在同样条件下游离酶液仅为36.5%。 展开更多
关键词 反胶束体系 稳定性 青霉素酰化酶 十六烷基三甲基溴化铵 酶活性 Β-内酰胺 抗生素
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固定化青霉素酰化酶的新载体 被引量:8
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作者 任玲玲 何静 +1 位作者 马润宇 段雪 《北京化工大学学报(自然科学版)》 CAS CSCD 2002年第1期64-67,共4页
通过X射线粉末衍射、红外光谱等手段考察了α 磷酸锆层柱材料作为载体固定青霉素酰化酶及其对载体结构影响。结果表明无论是否加入戊二醛固定化酶后 ,层柱材料的结晶度都下降。酶活性和回收率较高 ,分别为139 5nmol/s和 2 8 9%。间歇操... 通过X射线粉末衍射、红外光谱等手段考察了α 磷酸锆层柱材料作为载体固定青霉素酰化酶及其对载体结构影响。结果表明无论是否加入戊二醛固定化酶后 ,层柱材料的结晶度都下降。酶活性和回收率较高 ,分别为139 5nmol/s和 2 8 9%。间歇操作稳定性较好 ,连续操作 10次 ,酶活性下降 2 4% 展开更多
关键词 Α-磷酸锆 三乙烯四胺 青霉素酰化酶 插层组装 固定化 载体 Β-内酰胺类抗生素
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粪产碱杆菌青霉素G酰化酶在大肠杆菌中组成型表达及分离纯化 被引量:11
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作者 杨志建 蔡谨 +1 位作者 孙健 袁中一 《生物工程学报》 CAS CSCD 北大核心 2004年第5期736-740,共5页
将粪产碱杆菌青霉素G酰化酶基因构建重组表达质粒pKKFPGA ,pKKFPGA再转化宿主菌DH5α,所得重组菌不需诱导便能高效表达青霉素G酰化酶 ,表达量达 2 5 90u L ,比野生型粪产碱杆菌表达量高 4 32倍 ,其菌体比活力达 30 0 (u L) A6 0 0 。... 将粪产碱杆菌青霉素G酰化酶基因构建重组表达质粒pKKFPGA ,pKKFPGA再转化宿主菌DH5α,所得重组菌不需诱导便能高效表达青霉素G酰化酶 ,表达量达 2 5 90u L ,比野生型粪产碱杆菌表达量高 4 32倍 ,其菌体比活力达 30 0 (u L) A6 0 0 。菌体破碎后的上清液经DEAE_SepharoseCL 6B离子交换层析和Butyl_SepharoseCL 4B疏水层析 ,即可得纯度提高 2 0倍、比活为 6 8 6u mg的青霉素G酰化酶 ,两步纯化的总收率达 91%。Western印迹分析表明 5 %的原前体青霉素酰化酶在胞内形成了包涵体 。 展开更多
关键词 青霉素G酰化酶 粪产碱杆菌 表达 纯化 包涵体 大肠杆菌
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介孔材料MCFs的合成及组装青霉素酰化酶的性质研究 被引量:14
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作者 高波 陈静 +3 位作者 朱广山 傅学奇 王春雷 裘式伦 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2004年第11期1998-2000,共3页
Silica mesoporous material MCFs with 16.0 nm pore sizes was prepared by using non-ionic block copolymers and the swelling agents, and was used as the support for the immobilization of enzyme. Penicillin G acylase, an ... Silica mesoporous material MCFs with 16.0 nm pore sizes was prepared by using non-ionic block copolymers and the swelling agents, and was used as the support for the immobilization of enzyme. Penicillin G acylase, an enzyme, was assembled in the channel of MCFs by immersion method. The activity and stability of immobilized penicillin G acylase were studied. It was found that the activity and stability of the immobilized penicillin G acylase increased significantly compared to those of free enzyme. The optimum reaction temperature is 60 ℃. After incubation at 60 ℃ for 1 h, the activity of these immobilized penicillin G acylase remains 69%. These results showed that thermostability and durability on heating of the immobilized penicillin G acylase in MCFs was improved remarkably. The silica mesoporous material MCFs with 3-dimensional channel structure is a good support for the immobilization of enzyme. 展开更多
关键词 介孔材料MCFs 青霉素酰化酶 活性 稳定性
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固定化青霉素酰化酶在DMSO-水介质中催化合成头孢氨苄 被引量:7
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作者 詹选治 杨晟 +3 位作者 王峥 朱振勤 杨蕾 袁中一 《药物生物技术》 CAS CSCD 2001年第4期192-196,共5页
与传统的化学方法相比较 ,酶法合成头孢菌素工艺具有明显优点 ,通过酶的固定化与非水相酶催化技术相结合为提高产率找到了简捷的途径。实验以 7 氨基 3 脱乙酰氧基头孢烷酸 (7 amino 3 deactoxycephalosporanic,7 ADCA)为母核 ,苯甘氨... 与传统的化学方法相比较 ,酶法合成头孢菌素工艺具有明显优点 ,通过酶的固定化与非水相酶催化技术相结合为提高产率找到了简捷的途径。实验以 7 氨基 3 脱乙酰氧基头孢烷酸 (7 amino 3 deactoxycephalosporanic,7 ADCA)为母核 ,苯甘氨酸甲酯盐酸盐 (D phenylglycinemethylesterchlorohydrate ,PGME)为酰基供体 ,在二甲亚砜 (DMSO) 水共溶剂体系中 ,采用聚丙烯腈纤维固定化青霉素酰化酶 (penicillinacylaseEC3 .5 .1.11,PA)催化合成头孢氨苄 (Cephalexin)。发现DMSO浓度、反应温度、pH、底物浓度等对转化率均有影响。在 2 5℃ ,pH6 .5 ,40 %DMSO 水体系中 ,7 ADCA、PGME浓度分别为 85mmol/L ,12 8mmol/L时 ,7 ADCA转化率达 90 %。在 15次反复合成Cephalexin期间 ,转化率保持 90 展开更多
关键词 青霉素酰化酶 头孢氨苄 非水介质 酶催化 DMSO 水介质 催化
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大孔聚甲基丙烯酸缩水甘油酯固定化酶载体的合成及性能研究 被引量:18
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作者 乌云高娃 卢冠忠 +2 位作者 郭杨龙 王筠松 魏东芝 《化学学报》 SCIE CAS CSCD 北大核心 2002年第3期504-508,共5页
选用反应性单体甲基丙烯酸缩水甘油酯 ,以N ,N′ 亚甲基双 (丙烯酰胺 )为交联剂 ,甲酰胺为致孔剂 ,用反相悬浮聚合方法制得一系列珠状共聚物载体 ,通过测定其表面的物化性能、表面的环氧基浓度和固定青霉素酰化酶活性 ,讨论了交联剂用... 选用反应性单体甲基丙烯酸缩水甘油酯 ,以N ,N′ 亚甲基双 (丙烯酰胺 )为交联剂 ,甲酰胺为致孔剂 ,用反相悬浮聚合方法制得一系列珠状共聚物载体 ,通过测定其表面的物化性能、表面的环氧基浓度和固定青霉素酰化酶活性 ,讨论了交联剂用量、配比及合成条件对共聚物表面性能和固定化青霉素酰化酶活性的影响 . 展开更多
关键词 大孔聚甲基丙烯酸缩水甘油酯 固定化酶 载体 合成 反相悬浮聚合 青霉素酰化酶
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微波辐射高效共价固定青霉素酰化酶 被引量:10
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作者 王华 王安明 +3 位作者 周成 祝社民 宗璟 沈树宝 《化学学报》 SCIE CAS CSCD 北大核心 2008年第2期271-275,共5页
为提高青霉素酰化酶的共价固定化效率,在微波辐射条件下将酶蛋白共价固定于介孔泡沫硅(MCFs)的孔道中通过正硅酸四乙酯水解缩合制备介孔泡沫硅,再于微波辅助下将青霉素酰化酶其价固定在其孔道中.以固定化酶相对活力和活力回收为指标,考... 为提高青霉素酰化酶的共价固定化效率,在微波辐射条件下将酶蛋白共价固定于介孔泡沫硅(MCFs)的孔道中通过正硅酸四乙酯水解缩合制备介孔泡沫硅,再于微波辅助下将青霉素酰化酶其价固定在其孔道中.以固定化酶相对活力和活力回收为指标,考察了加酶量、固定化温度、微波辐射时间等条件对酶固定化效率的影响.实验结果表明:当加酶最为60 mg/g,固定化温度为20℃,微波辐射140 s,固定化酶相对活力达到178.1%,表观活力为1191.3 U/g(以湿重计).与常规方法相比,微波辅助固定化酶时,固定化酶相对活力提高34.5%,固定化时间亦大幅缩短至数分钟,这为青霉素酰化酶的高效共价固定化提供了一条新的途径. 展开更多
关键词 微波辐射 青霉素酰化酶 介孔泡沫硅(MCFs) 固定化酶
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