Microdetermination of Residual Protein in Penicillin by Resonance Light Scattering Technique with m-Nitrophenylfluorone-Mo(VI) Complex

Use of penicillin may cause allergic sensitivity in many individuals. The content of residual proteins in penicillin may be the antigenicity substances that may cause allergic reaction in case of excess. On the other hand, an excess of residual protein leads to many problems in technology such as high viscosity, difficulties in filteration, a lot of foam, time-consuming etc. And the yield of penicillin is affected consequently. Therefore, content of residual protein in penicillin must be contr…     

含环氧基的交联聚合物载体的制备方法对固定化青霉素酰化酶活性的影响

 以甲基丙烯酸缩水甘油酯为单体，N，N′－亚甲基双丙烯酰胺为交联剂，采用两种方法合成了大孔、珠状的交联聚合物固定化酶载体．用红外光谱、扫描电子显微镜及N2吸附等方法测定了其结构、比表面积、孔径分布和表观活性．结果表明，以液体石蜡为主介质、甲醇水溶液为致孔剂合成的聚合物GM1（60）作载体时，固定化酶水解青霉素G的活性达537U／g；以正庚烷与四氯乙烯混合溶剂为介质、甲酰胺为致孔剂合成的聚合物GM2（60）作载体时，固定化酶的活性较低，为426U／g．在37℃下连续进行10次间歇操作（每次反应10min）后，前者活性降至487U／g，保持了初始活性的90．7％；后者活性降至378U／g，保持了初始活性的88．7％．二者催化活性的不同是由于两种方法制备的载体在结构与性能上存在着明显的差异．GM1（60）载体孔径大，水中溶胀性能好，对青霉素酰化酶的偶联作用强，固定化效果显著．     

Efficient continuous kinetic resolution of racemic 2-aminobutanol over immobilized penicillin G acylase

In this paper, an efficient method was established for continuous kinetic resolution of racemic 2-aminobutanol by selective hydrolysis of N-phenylacetyl (±)-2-aminobutanol over immobilized penicillin G acylase (PGA) in a fixed-bed reactor. Several N-acylated derivatives of 2-aminobutanol were screened in batch experiments, and it was found that the hydrolysis of N-phenylacetyl (±)-2-aminobutanol proceeded smoothly in the presence of immobilized penicillin G acylase with satisfied enantioselectivity. Thus, the reaction parameters were optimized in a fixed-bed reactor. Under the optimized conditions, 39.3% conversion of N-phenylacetyl (±)-2-aminobutanol and 98.2% ee value of S-2-aminobutanol were obtained. This fixed-bed system was operated continuously for 40 h without significant decrease of enzyme activity. It has been demonstrated to be more efficient compared to the batch experiments.     

青霉素G亚砜对-甲氧基苄基酯的制备

青霉素亚砜;合成;青霉素G亚砜对-甲氧基苄基酯的制备     

酶作用下双金属复合氧化物记忆效应与其组成的关系

水滑石;青霉素酰化酶;固定化酶;酶作用下双金属复合氧化物记忆效应与其组成的关系     

共价三嗪骨架吸附剂-固相萃取-超高效液相色谱-串联质谱法测定牛奶中3种青霉素类残留

建立了固相萃取-超高效液相色谱-串联质谱法(SPE-UPLC-MS/MS)同时测定牛奶中苄青霉素、邻氯青霉素、氨苄青霉素3种青霉素残留的分析方法。以自制的共价三嗪骨架(CTFs)材料作为固相萃取吸附剂,对影响固相萃取柱效率的吸附剂填充量、洗脱剂种类和用量及上样速率等主要因素进行了优化;同时对样品的提取和净化条件进行了考察。在3 mL/min的样品流速下,采用60 mg CTFs吸附剂和6 mL纯乙腈洗涤液达到了最佳的萃取效果。以0.1%甲酸水溶液-乙腈作为流动相进行梯度洗脱,在Waters ACQUITY UPLC BEH C18色谱柱上分离,电喷雾正离子(ESI⁺)模式下以动态多反应监测(MRM)采集数据,外标法定量。3种目标分析物的线性回归方程相关系数均大于0.999,检出限(LOD)为0.05~0.10 μg/kg(信噪比S/N=3),定量限(LOQ)为0.1~0.4 μg/kg(S/N=10),加标回收率为84.9%~94.1%,相对标准偏差(RSD, n=5)为1.66%~3.27%。此外,共价三嗪骨架材料与目标物的作用机理研究表明,主客体分子间存在π-π相互作用和氢键作用等多重相互作用,使该吸附剂可成功用于牛奶中青霉素的富集和净化。该方法具有精密度较高、重复性较好、分离度高、分析时间短等优点,可适用于牛奶中青霉素定性定量测定。     

青霉素G钾盐对SDS水溶液物理化学性质的影响及其在SDS/n-C5H11OH/H2O体系中的释放

The effects of penicillin potassium salt （PenK） on the solubility, Krafft temperature TK, critical micelle concentration CMC of SDS micelle and the phase behavior of SDS/n-C5H11OH/H2O system were studied. The partial phase diagrams of SDS/PenK/H2O system at different temperatures were determined. The release amounts of PenK in SDS/n-C5H11OH/H2O system and the distribution coefficient of PenK between micelle and water were measured by UV-Vis spectroscopy. The results show that in the presence of PenK, the CMC of SDS was decreased while the TK of SDS was increased and the solubility of SDS in both water and SDS/n-C5H11OH/H2O oil in water （O/W） microemulsion was decreased, but increased in water in oil （W/O） microemulsion. SDS micelles and SDS/n- C5H11OH/H20 O/W microemulsion could accelerate the release rate of PenK. The addition of SDS and water could both increase the release rate of PenK, whereas the presence of n-C5H11OH reduced the release rate of PenK. The above results were related to the electrostatic repulsion between PenK and SDS.     

An efficient synthesis of ampicillin on magnetically separable immobilized penicillin G acylase

<正>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 m~2/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.