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用设计的特殊摇瓶,以苏云金杆菌为研究对象,供冷模(亚硫酸盐氧化法)在求出瓶口过滤层氧通透率的基础上,由特制摇瓶在线检测发酵过程中气液相氧浓度变化数据,取得发酵过程中的菌体摄氧率、氧传递系数等有用的工程参数。 相似文献
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重组类人胶原蛋白的分离纯化 总被引:2,自引:0,他引:2
目的 建立重组类人胶原蛋白分离及纯化工艺。方法 将工程菌株E.coli BL21 3.1在L1523型12.8L自控发酵罐中培养14h,发酵菌体经超声破碎、硫酸铵沉淀后,依次经DEAE-52和Sephadex G-100柱层析分离纯化。结果 发酵菌体干重达到71g/L,表达量为菌体蛋白量的29.4%,最终产物纯度达98%,回收率为80.5%,纯化倍数为3.4。结论 纯化的类人胶原蛋白达电泳纯,相对分子质量为90 000,N端序列为NH_2-H-D-P-V-V-L-Q-R-R-D-W-E-N-P-G,均与其因序列设计一致。 相似文献
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The feeding method of propionic acid for production of poly (3-hydroxybutyrate-co-3-hydro xyvalerate)[P(3HB-co-3HV)]by fed-batch culture of Ralstonia eutropha was optimized to achieve high cell density and high 3HV yield,Effects of different feeding strategies of propionic acid on the production of P(3HB-co-3HV) were investigated,A decline of specific synthesis rate of copolymer and the yield of 3HV unit from propionic acid were observed due to the propionic acid accumulation in culture broth when the feeding solution with high P/G(ropionic acid to glucose) ration was employed,It was further confirmed by controlling propionic acid concentration at a low leve in the separate feeding of propionic acid.An optimed feeding strategy was demonstrated to reduce the propionic acid accumulation ,The cell concentration,P(3HB-co-3HV) productivity and 3HV unit fraction reached to 163.9 kg.m^-3,1.8kg.m^-3.h^-1,and 10.6%(by mass),respectively,resulting in a yield of 0.33g HV per g propionic acid. 相似文献
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In order to improve the production of human-like collagen Ⅲ (HLC Ⅲ) by fed-batch culture of recom-binant Escherichia coli BL21, the Plackett-Burman and Box-Behnken design were applied to optimize the fermen-tation process parameters.Three variables (induction time, inoculum age and pH), which have significant effects on HLC Ⅲ production, were selected from eight variables by Plackett-Burman design.With the regression coefficient analysis in the Box-Behnken design, a relationship between HLC Ⅲ production and three significant factors was obtained, and the optimum levels of the three variables were as follows: induction time 3.2h, inoculum age 12.6 h and pH 6.7.The 3D response surface plots and 2D contour plots created by the Box-Behnken design showed that the interaction between induction time and pH and that between innoculum age and pH were significant.An aver-age 9.68 g·L~(-1)HLC Ⅲ production was attained in the validation experiment under optimized condition, which was 80% higher than the yield of 5.36 g·L~(-1) before optimization. 相似文献
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随着可持续发展理念的强化、新兴技术的快速发展和生物制造产业重要性的日益凸显,生物化工在未来生物制造和生物经济竞争中的地位更加显著。培养掌握先进生物化工技术、秉持可持续发展理念的生物化工领域创新人才,成为国家在未来竞争中保持主动的关键。文章对西安交通大学生物化工学科研究生培养实践进行了总结,介绍了知识平台、科研实践平台、人才培养模式和质量监控体系建设等创新人才培养举措,以期为生物化工人才培养提供有益的借鉴,助力国家生物制造战略的实施。 相似文献
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采用一株具有较高硫酸盐还原活性的路德维希肠杆菌(SRB-2)处理含镉溶液,测定了SRB-2在含镉溶液中的生长、硫酸盐还原活性、溶液p H及Cd2+质量浓度等的变化,初步分析了该菌株对溶液中镉的去除效应。实验结果表明:SRB-2在含有100 mg/L Cd2+的溶液中生长良好,且随着SRB-2的生长繁殖,溶液的p H值从7.0升高到7.4,这可能有助于Cd2+在溶液中形成沉淀从而被去除,其硫酸盐还原率最高为62.18%;SRB-2在Cd2+质量浓度为50mg/L和100 mg/L的溶液中分别培养15 d后,溶液中Cd2+去除率均达到98%。SRB-2能够在含镉质量浓度较高的溶液中良好生长,且对硫酸盐和Cd2+有较好的去除率。 相似文献
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考察离子液体溴化-1-乙基-3-甲基咪唑([emim]Br)作为提取溶剂对中草药中白桦脂酸衍生物的提取特性,并找到最佳提取条件。以中草药皂角刺为原料,以离子液体溴化-1-乙基-3-甲基咪唑为提取溶剂,选取提取温度、提取时间和液固比3个因素,进行正交试验,考察提取得率,并与乙醇回流提取方式作对比,找到离子液体提取最佳条件。结果表明:乙醇回流提取对目标成分的提取得率为0.050%,离子液体溴化-1-乙基-3-甲基咪唑在不同条件下对目标成分的提取得率为0.079%—0.107%。在室温(25℃)、液固比30∶1、提取时间2 h的条件下离子液体对目标成分的提取得率为0.105%。离子液体溴化-1-乙基-3-甲基咪唑对中草药皂角刺中白桦脂酸衍生物的提取得率明显高于乙醇回流提取方式的提取得率,最佳提取条件为室温(25℃)、液固比30∶1,提取时间2h。 相似文献
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