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Chinese Journal of Chemical Engineering 2018年第1期26卷 207-212页

作者： Xin Xin yixin guan Shanjing Yao College of Chemical and Biological Engineering Zhejiang University

Scaffolds with multimodal pore structure are essential to cells differentiation and proliferation in bone tissue engineering. Bi-/multi-modal porous PLGA/hydroxyapatite composite scaffolds were prepared by supercritical C02 foaming in which hydroxyapatite acted as heterogeneous nucleation agent. Bimodal porous scaffolds were prepared under certain conditions, i.e. hydroxyapatite addition of 5%, depressurization rate of 0.3 MPa. min-1, soaking temperature of 55 ℃, and pressure of 9 MPa. And scaffolds presented specific structure of small pores （122 μM ± 66 μm） in the cellular walls of large pores （552 μm ±127 μm）. Furthermore, multimodal porous PLGA scaffolds with micro-pores （37 μM ± 11μM） were obtained at low soaking pressure of 7.5 MPa. The interconnected porosity of scaffolds ranged from （52.53 ± 2.69）% to （83.08±2.42）% by adjusting depressurization rate, while compression modulus satisfied the requirement of bone tissue engineering. Solvent-free CO2 foaming method is promising to fabricate bi-/multi-modal porous scaffolds in one step, and bioactive particles for osteogenesis could serve as nucleation agents.

关键词： Supercritical carbon dioxide Foam Tissue engineering PLGA scaffolds Hydroxyapatite Bi-/multi-modal pore

Optimizational production of phenyllactic acid by a Lactobacillus buchneri strain via uniform design with overlay sampling methodology

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Chinese Journal of Chemical Engineering 2019年第2期27卷 418-425页

作者： Jintao guan Chaofei Han yixin guan Songhong Zhang Junxian Yun Shanjing Yao College of Chemical and Biological Engineering Zhejiang University State Key Laboratory Breeding Base of Green Chemistry Synthesis Technology College of Chemical Engineering Zhejiang University of Technology

A Lactobacillus buchneri GBS3 strain isolated from the traditional Chinese pickles was used for the production of 3-phenyllactic acid(PLA), an important compound with antimicrobial activities against a wide species of grampositive and gram-negative bacteria and some fungi. The growth performance of this strain in the de Man, Rogosa and Sharpe(MRS) medium, the production of metabolites of valuable organic acids, and the biosynthesis of PLA using this strain as the whole-cell biocatalyst and phenylpyruvic acid(PPA) as the precursor, were investigated experimentally. The uniform design method with overlay sampling was developed for the optimization of the biotransformation conditions. The results showed that although it produced naturally lactic acid with the maximum concentration of 1.84 g·L^(-1) and PLA with the concentration of 0.015 g·L^(-1) after 66 to 72 h cultivation in MRS broth by fermentation, the present strain displayed an effective utilization ability by transforming PPA to PLA. By the uniform design method with overlay sampling for the design and optimization of transformation conditions, a maximum yield of 10.93 g·L^(-1) PLA with the mole conversion ratio of 83.07% from PPA to PLA was achieved under the optimized condition, i.e., 20 g·L^(-1) glucose, 270 g·L^(-1) cells, 13 g·L^(-1) PPA, pH 8.0 and the reaction time of 15 h, indicating that Lactobacillus buchneri GBS3 was an interesting strain for the biosynthesis of PLA via the microbial transformation. The prediction of PLA yield under different conditions was achieved successfully based on the limited information of only a small number of experiments by the uniform design with overlay sampling. Therefore, the present methodology is effective and helpful for the optimization of the biosynthesis processes of PLA.

关键词： Phenyllactic Acid Biotransformati on Lactobacillus Buchneri Uniform Design Overlap Sampling

Optimization of DsbA Purification from Recombinant Escherichia coli Broth Using Box-Behnken Design Methodolog

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Chinese Journal of Chemical Engineering 2013年第2期21卷 185-191页

作者： LUO Man guan yixin YAO Shanjing Department of Chemical and Biological Engineering Zhejiang University Hangzhou 310027 China

Disulfide bond formation protein A （DsbA） is one of the important helper proteins for folding in protein synthesis in vivo. In this study, purification of recombinant DsbA was investigated by examining four important factors with Box-Behnken design method, a statistic-based design of experiments. The optimal operation conditions were obtained by adopting the effectiveness coefficient method on the multi-objective problem, which takes the protein recovery, purification efficiency and throughput of ion-exchange chromatography into account. After the optimization, protein recovery of 96.8% and purity higher than 95% DsbA was achieved, and the productivity was （377.9±1.7） mg soluble DsbA per liter broth. The purified protein was identified by peptide mass fingerprinting matching the record of gil2624856, a mutant of DsbA. The DsbA was preliminarily applied to the refolding of denatured lysozyme in vitro.

关键词： disulfide bond formation protein A protein purification Box-Behnken experiment design response surface methodology multi-object programming

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国际化战略七种模式正在浮出水面

理论前沿 2005年第16期 10-11页

作者：管益忻中国发展战略学会

本文分析了我国企业在实施“走出去”战略的过程中所形成的七种模式及特点,对于国内企业的国际化战略有借鉴意义。

关键词： “走出去”战略中国企业国际化模式

Influence of Osmoregulators on Osmotolerant Yeast Candida krusei for the Production of Glycerol

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Chinese Journal of Chemical Engineering 2006年第3期14卷 371-376页

作者：陈国姚善泾关怡新 Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China

Candida krusei was osmotolerant yeast for the production of glycerol. Extracellular osmotic pressure was one of the key factors to induce the enzyme activity of glycerol-3-phosphate dehydrogenase(GPDH) which se- verely affected the glycerol productivity. Three osmoregulators such as NaCl, PEG4000 and glycerol were used to investigate their effects on yeast growth, glucose consumption and glycerol production. In order to determine the effect of extracellular glycerol concentration, different amounts of glycerol were initially supplemented as an os- moregulator to increase glycerol production. The maximum glycerol concentration attained 179g L-1 with initial glycerol concentration of 80g L-1 in medium, compared with 41g L-1 in the control experiment. These results were successfully reproduced for fed-batch process in an air-lift reactor.

关键词： Candida krusei glycerol osmotolerant yeast osmoregulator air-lift reactor

直面客户经济,再造企业核心能力机制——大力推进企业范式创新战略转型

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理论前沿 2006年第6期 15-17页

作者：管益忻中国发展战略学研究会

文章通过对10种实现企业主体创新以至商业模式战略转变的分析,提出了对再造企业核心能力机制的思考。

关键词：战略转变商业模式企业核心能力机制

超临界辅助雾化制备适于气溶胶给药的药物微粒

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化工学报 2005年第2期56卷 187-196页

作者：朱自强关怡新姚善泾浙江大学化学工程与生物工程学系浙江杭州310027

超临界流体辅助雾化法 (SAA) 是一种新型的以超临界流体为基础的固体微粒制备工艺, 既能用于水溶性, 也可用于脂溶性的溶质. 该工艺能制备出适用于气溶胶给药要求的微粒, 预期可在药物行业内得到应用.综述了SAA过程的形成和特色、工艺... 详细信息

超临界流体辅助雾化法 (SAA) 是一种新型的以超临界流体为基础的固体微粒制备工艺, 既能用于水溶性, 也可用于脂溶性的溶质. 该工艺能制备出适用于气溶胶给药要求的微粒, 预期可在药物行业内得到应用.综述了SAA过程的形成和特色、工艺流程和操作条件以及相应的造粒结果. 评述了 6 种药物微粒的粒度、粒度分布及其形貌. 经SAA加工后的药物质量未见变化, 目前该工艺已进入中试阶段, 展示出较快的发展速度. 比较了SAA和现有的主要以超临界流体为基础的微粒制造工艺. 展望了加强应用基础研究的必要性, 进一步分析了SAA的机理和过程实质.

关键词：超临界流体辅助雾化气溶胶给药配方药物微粒制备

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疏水层析法复性重组人γ干扰素

化工学报 2005年第6期56卷 1076-1080页

作者：关怡新潘海学姚善泾浙江大学化学工程与生物工程学系浙江杭州310027

重组人γ-干扰素(rhIFN-γ)在大肠杆菌中高效表达,并形成包涵体.利用疏水作用层析(HIC)法对rhIFN-γ进行复性.采用了等尿素梯度和线性尿素梯度两种复性方法,考察了线性尿素梯度下尿素梯度长度、尿素终浓度、流速和上样量对rhIFN-γ复性... 详细信息

重组人γ-干扰素(rhIFN-γ)在大肠杆菌中高效表达,并形成包涵体.利用疏水作用层析(HIC)法对rhIFN-γ进行复性.采用了等尿素梯度和线性尿素梯度两种复性方法,考察了线性尿素梯度下尿素梯度长度、尿素终浓度、流速和上样量对rhIFN-γ复性的影响.在优化的线性尿素梯度复性条件下,尿素浓度在10个柱体积内从6mol·L-1下降到2mol·L-1,流速为1ml·min-1、上样量为0.568mg时,rhIFN-γ的活性收率比稀释复性法提高6.5倍,蛋白质量收率为36%,比活达1.9×108IU·mg-1.

关键词：疏水作用层析重组人γ-干扰素包涵体蛋白质复性

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重组瑞替普酶包涵体制备及其体外复性

化工学报 2015年第2期66卷 709-716页

作者：王俊雄关怡新姚善泾浙江大学化学工程与生物工程学院浙江杭州310027

将携带重组瑞替普酶(reteplase,rt-PA)的质粒成功转化到大肠杆菌BL21(DE3)后,诱导表达获得包涵体,考察了诱导剂浓度、培养温度和培养时间等条件对目标蛋白表达量的影响。在此基础上,对高效表达的rt-PA包涵体体外复性过程进行了详细研究... 详细信息

将携带重组瑞替普酶(reteplase,rt-PA)的质粒成功转化到大肠杆菌BL21(DE3)后,诱导表达获得包涵体,考察了诱导剂浓度、培养温度和培养时间等条件对目标蛋白表达量的影响。在此基础上,对高效表达的rt-PA包涵体体外复性过程进行了详细研究。首先利用单因素实验考察了复性液p H、GSH浓度、GSH/GSSG比例、蛋白浓度等各种复性条件对复性效果的影响;并结合正交实验设计,进一步研究了高蛋白浓度下复性后rt-PA酶活变化情况。以0.2 mmol·L-1 IPTG诱导,在33℃下培养6 h,每升发酵液约可获得1.7 g粗制包涵体。适宜的复性条件为蛋白浓度50μg·ml-1,p H 10.0,GSH浓度1 mmol·L-1,GSH/GSSG比例8,复性收率为87.2%。影响高蛋白浓度下rt-PA复性的关键因素为复性液初始p H及GSH浓度,在800μg·ml-1蛋白浓度下复性后rt-PA比活可达7.54×104 IU·mg-1,荧光光谱分析结果表明复性后rt-PA恢复了其天然态结构。

关键词：生物分离蛋白质复性二硫键正交实验设计瑞替普酶

高压CO_2条件下粗状假丝酵母催化苯乙酮不对称还原合成α-苯乙醇

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催化学报 2006年第7期27卷 631-635页

作者：应小姣姚善泾关怡新浙江大学化学工程与生物工程学系浙江杭州310027

研究了在高压CO7条件下利用粗状假丝酵母Candida valida CICCl444活性细胞催化苯乙酮不对称还原合成（R）-α-苯乙醇．高压C02条件可对粗状假丝酵母细胞的活性产生一定的影响，但反应的选择性反而有所提高，证实了高压CO2作为该反应环... 详细信息

研究了在高压CO7条件下利用粗状假丝酵母Candida valida CICCl444活性细胞催化苯乙酮不对称还原合成（R）-α-苯乙醇．高压C02条件可对粗状假丝酵母细胞的活性产生一定的影响，但反应的选择性反而有所提高，证实了高压CO2作为该反应环境是可行的．考察了底物浓度、细胞用量、反应温度和压力等因素对反应的影响．结果表明，这些因素对反应产率有很大的影响，在最佳反应条件下，反应底物苯乙酮的转化率和产物α-苯乙醇的产率均可达90％以上，对映体过量值（ee）保持在80％左右．与常压静置条件下的反应相比，高压CO2条件下粗状假丝酵母催化苯乙酮不对称还原反应的转化率和产率分别提高了20％和40％左右，对映体选择性也提高了5％～10％．

关键词：高压二氧化碳粗状假丝酵母全细胞生物催化苯乙酮不对称还原 α-苯乙醇