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21.
冻干腮腺炎活疫苗细胞培养生产工艺研究 总被引:1,自引:0,他引:1
报告了冻干腮腺炎活疫苗细胞培养生产工艺研究结果,通过对鸡胚疫苗株的适应培养及对细胞培养生产工艺的试验优化,建立了连续细胞培养多次收获疫苗生产工艺并制备出了冻干细胞培养腮腺炎活疫苗制剂。本生产工艺切实可行,生产成本低、投入产出率高,所用原材料规范、质量易于控制,具有明显的技术优势。生产的冻干疫苗制剂质量稳定可靠,符合中国生物制品规程要求,有利于预防腮腺炎的规模化推广使用 相似文献
22.
Predictions of matrix‐assisted refolding of α‐lactalbumin: Process efficiency versus batch dilution method
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Protein refolding is an important technique to produce active recombinant proteins from inclusion bodies. Because of the complexity of the refolding process, a trial‐and‐error method is usually used for its design, which is ineffective and time consuming. Therefore, an efficient method for the process prediction is indispensable to optimize the operating conditions. In this article, we suggest a design procedure for matrix‐assisted protein refolding. Three different chromatographic techniques were considered exploiting hydrophobic interaction chromatography, ion‐exchange chromatography, and SEC media. The procedure consisted of quantification of refolding kinetics, analysis of the retention behavior of all protein forms involved in refolding, construction of a dynamic model, and the process simulation. Denatured bovine α‐lactalbumin was used as model protein. The refolding rate was measured for different protein concentration using the batch dilution method. A kinetic scheme for the protein refolding was suggested and incorporated into a dynamic model of chromatographic column and used for predicting the refolding performance. The productivity, yield, and buffer consumption were used as performance indicators for the refolding techniques considered. The matrix‐assisted protein refolding process outperformed batch dilution method with respect to all indicators provided that efficient method for the process design was used. 相似文献
23.
Riparian wetlands are important components of the lake ecosystem, and they play essential roles in maintaining system health.
Remediation of degraded lakeshore wetlands is an essential component of lake restoration. A study was conducted to investigate
the restoration of lakeshore wetlands, which were converted to rice fields and then abandoned for 2, 5, 10 and 15 years, near
Lake Taihu. Soil samples (0–20 cm and 20–40 cm) were taken and plant species were investigated. The carbon content in the
soil had increased significantly, rising from 0.71% to 1.85% between 2 and 15 years. Organic matter accumulation improved
soil texture, and water stable aggregate content (>0.25 mm) and soil porosity increased. Total nitrogen in the soil increased
from 0.06% to 0.13%, and total Kjeldahl nitrogen increased from 124.4 mg kg−1 to 351.5 mg kg−1. Total phosphorus in the soil increased from 0.045% to 0.071%, and the Olsen-P value increased from 5.13 mg kg−1 to 16.0 mg kg−1. Results showed that phosphorous did not increase as much as nitrogen. In the vegetation restoration process, plant species
composition moved towards a natural wetland community, and spatial heterogeneity and landscape diversity increased. The richness
of plant biodiversity increased rapidly in the first 2 years, then more slowly in later restoration stages. The wetlands recovery
process may be complicated by interactions of biota and soil and hydrological conditions. 相似文献
24.
Walter Cabri 《Rendiconti Lincei》2007,18(4):271-280
Catalysis is the key technology for the development of green processes for the industrial production of active pharmaceutical
ingredients. The design of green, efficient and cost competitive industrial process of idarubicin, erlotinib and ivermectin
shows the central role of catalysis.
Riassunto La catalisi: tecnologia fondamentale per it design di processi industriali a basso impatto ambientale nell'industria farmaceutica. La catalisi è la tecnologia fondamentale per lo sviluppo di processi industriali ?green?, efficienti e a basso costo per la produzione di idarubicina, erlotinib e ivermectina, dimostra il ruolo centrale dei processi catalitici.相似文献
25.
Mohammadian-Mosaabadi J Naderi-Manesh H Maghsoudi N Nassiri-Khalili MA Masoumian MR Malek-Sabet N 《Protein expression and purification》2007,51(2):147-156
Process development and optimization studies were performed in order to improve the purification process of (rhIFN-gamma). The objective was to generate material with higher purity and quantity. An in-process control screening was developed to obtain the optimal condition for column chromatographic purification by measuring LPS, nucleic acids, rhIFN- gamma, monomer and its covalent dimers. A new resin screening method was applied to select optimal resin for each of the chromatographic columns. The resulting process used Butyl and Q-Sepharose, refolding and SP-Sepharose for purification of IFN-gamma. Effects of different process conditions such as cell lysis, removal of impurity and oxygen concentration were evaluated. Removal of impurities was evaluated by washing of inclusion bodies with 1% Triton X-100 and 3M urea and different chromatography steps. The results reveal that Triton removed about 43% of the LPS but urea had no effect on removal of nucleic acids and LPS. Further analysis show that removal of impurities by column chromatography decreases aggregation and increases the process yield. Oxygen concentration was identified as parameter that could have a significant impact on covalent dimers formation, as an unacceptable pharmaceutical form of rhIFN-gamma. On the basis of small-scale studies, optimum operating conditions were chosen and the purification process was successfully scaled-up to a pilot scale process with step yield and product quality that were better than previous reports. 相似文献
26.
Gueguim-Kana EB Oloke JK Lateef A Zebaze-Kana MG 《Journal of industrial microbiology & biotechnology》2007,34(7):491-496
The acidification behavior of Lactobacillus bulgaricus and Streptococcus thermophilus for yoghurt production was investigated along temperature profiles within the optimal window of 38–44 °C. For the optimal
acidification temperature profile search, an optimization engine module built on a modular artificial neural network (ANN)
and genetic algorithm (GA) was used. Fourteen batches of yoghurt fermentations were evaluated using different temperature
profiles in order to train and validate the ANN sub-module. The ANN captured the nonlinear relationship between temperature
profiles and acidification patterns on training data after 150 epochs. This served as an evaluation function for the GA. The
acidification slope of the temperature profile was the performance index. The GA sub-module iteratively evolved better temperature
profiles across generations using GA operations. The stopping criterion was met after 11 generations. The optimal profile
showed an acidification slope of 0.06117 compared to an initial value of 0.0127 and at a set point sequence of 43, 38, 44,
43, and 39 °C. Laboratory evaluation of three replicates of the GA suggested optimum profile of 43, 38, 44, 43, and 39 °C
gave an average slope of 0.04132. The optimization engine used (to be published elsewhere) could effectively search for optimal
profiles of different physico-chemical parameters of fermentation processes. 相似文献
27.
The bio-flocs technology (BFT) was applied in the sequencing batch reactor (SBR) to treat aquaculture wastewater for flocs poly-β-hydroxybutyrate (PHB) accumulation with alternant anaerobic and aerobic conditions. The statistical modeling approach was used to evaluate system performance and to optimize the flocs PHB yield at batch mode. The results show that all variables have significant impact on the response objective, as well as the interactions of the C/N ratio with the flocs biomass concentration (VSS) and anaerobic time, respectively. By process optimization, approximately 150-200 PHB/VSS (mg·g) of flocs PHB yield was achieved in the range of 4-7 g/l of flocs biomass concentration, 15-18 of the C/N ratio and 50-85 min of anaerobic time in the BFT systems. The results demonstrated that a suitable flocs PHB yield can be obtained via optimizing the ex-situ operating strategy, which have potential prebiotic value and practical implication for the sustainable aquaculture. 相似文献
28.
Furfural production from xylose using sulfonic ion-exchange resins (Amberlyst) and simultaneous stripping with nitrogen 总被引:1,自引:0,他引:1
Agirrezabal-Telleria I Larreategui A Requies J Güemez MB Arias PL 《Bioresource technology》2011,102(16):7478-7485
The aim of this work deals with the development of new approaches to the production of furfural from xylose. It combines relatively cheap heterogeneous catalysts (Amberlyst 70) with simultaneous furfural stripping using nitrogen under semi-batch conditions. Nitrogen, compared to steam, does not dilute the vapor phase stream when condensed. This system allowed stripping 65% of the furfural converted from xylose and almost 100% of selectivity in the condensate. Moreover, high initial xylose loadings led to the formation of two water-furfural phases, which could reduce further purification costs. Constant liquid-vapor equilibrium along stripping could be maintained for different xylose loadings. The modeling of the experimental data was carried out in order to obtain a liquid-vapor mass-transfer coefficient. This value could be used for future studies under steady-state continuous conditions in similar reaction-systems. 相似文献
29.
“江苏省实验动物笼器具系列标准制订”获中国实验动物学会科学技术二等奖,系列标准研究共包括八项:《实验动物笼器具塑料笼箱》、《实验动物笼器具金属笼箱》、《实验动物笼器具笼架》、《实验动物笼器具层流架》、《实验动物笼器具饮水瓶》、《实验动物笼器具独立通气笼盒( IVC)系统》、《实验动物笼器具代谢笼》、《实验动物笼器具隔离器》.本文阐述了1)系列标准研究的背景;2)研究制订的过程,优势的先天条件,政府、专家、企业之间的联动配合,研究标准的创新意义;3)标准出台的效果,产业优势进一步扩大,社会效益明显. 相似文献
30.
David F Steinwand M Hust M Bohle K Ross A Dübel S Franco-Lara E 《Biotechnology journal》2011,6(12):1516-1531
Bacillus megaterium was used as an alternative high potential microbial production system for the production of antibody fragment D1.3 scFv. The aim of the study was to follow a holistic optimization approach from medium screening in small scale microtiter platforms, gaining deeper process understanding in the bioreactor scale and implementing advanced process strategies at larger scales (5-100 L). Screening and optimization procedures were supported by statistical design of experiments and a genetic algorithm approach. The process control relied on a soft-sensor for biomass estimation to establish a μ-oscillating time-dependent fed-batch strategy. Several cycles of growth phases and production phases, equal to starving phases, were performed in one production. Flow cytometry was used to monitor and characterize the dynamics of secretion and cell viability. Besides the biosynthesis of the product, secretion was optimized by an appropriate medium design considering different carbon sources, metal ions, (NH(4))(2)SO(4), and inductor concentrations. For bioprocess design, an adapted oscillating fed-batch strategy was conceived and successfully implemented at an industrially relevant scale of 100 L. In comparison to common methods for controlling fed-batch profiles, the developed process delivered increased overall productivities. Thereby measured process parameters such as growth stagnation or productivity fluctuations were directly linked to single cell or population behavior leading to a more detailed process understanding. Above all, the importance of single cell analysis as key scale-free tool to characterize and optimize recombinant protein production is highlighted, since this can be applied to all development stages independently of the cultivation platform. 相似文献