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关键词： 生长激素   Fc融合蛋白   CHO细胞   生物反应器   工艺放大  

摘要： 目的在NewBrunSwick31014 L生物反应器中培养表达重组人长效生长激素(recombinant human growth hormone Fc fusion protein,rhGH-Fc)的CHO细胞,优化工艺参数以提高表达量,并进行NewBrunSwick31014 L到New-BrunSwick51040 L生物反应器的工艺放大。方法在原有14 L培养工艺基础上,调节转速、通气速率等参数,并对参数调整时期进行工艺优化。通过对渗透压、乳酸、铵离子、钾离子等代谢过程产物的检测来确保代谢正常,利用HPLC法测定表达量。再根据经验公式算出可线性放大的体积依赖型参数,保持原有培养方案及补料策略不变的情况下,结合不同放大经验方法确定操作窗口,从而进行工艺放大。结果14 L生物反应器优化工艺乳酸累积量低于20 mmol/L、最终铵离子累积量为8 mmol/L、钾离子累积量为14 mmol/L、渗透压为425 osmol/kg,降温后比耗糖速率为0.12 g/(10^(9) cells·d),表达量为0.9 g/L。经检测,放大至40 L生物反应器,整个培养过程耗糖曲线及代谢产物均与14 L生物反应器中一致,表达量为1.0 g/L。结论成功优化了rhGH-Fc工程细胞大规模培养的工艺,并进行了规模放大,为rhGH-Fc的后续开发奠定了基础。

关键词： 活体组织   皮肤细胞   生物反应器   实验室   医学院   体内  

摘要： 最近,美国印第安纳大学医学院的研究人员开发了一个新型纳米芯片设备,该设备可以有效地将体内的皮肤细胞重新编程,成为新的血管和神经细胞。该芯片顶部是一个长方形的"容器",里面装有特定的基因。在聚焦电荷的推动下,这些基因被引入到活体组织所需的深度并改变细胞,进而将该位置转化为一个小小的生物反应器。反应器可以将细胞重新编程为不同种类的细胞或多细胞结构,如血管或神经,这一切无需复杂的实验室技术或危险的病毒转移系统。

关键词： 光生物反应器   猪场废水发酵液   藻菌共生体系   菌藻比  

摘要： 为了优化养猪废水发酵液生化处理方式,以小球藻和接种污泥构建藻菌共生体系,考察了藻菌比(1∶0,1∶0.2,1∶0.5,1∶1,1∶5)对微藻生长、组分积累及氮磷转化机制的影响。结果表明:微藻纯培养体系以脂质组分为主,藻菌共生体系在藻菌比为1∶0.2时的微藻浓度和微藻蛋白组分为800 mg·L^(-1)和56.8%;在藻菌协同作用下,通过同化作用去除的氮磷比例增加,脱氮途径主要为同化(38%)和硝化反硝化(62%),除磷主要为同化(18%)和化学沉淀(82%);当藻菌比为1∶0.2时,TP、TN及NH_(4)^(+)-N去除效果最佳,分别为76.0%,32.7%和31.7%;当藻菌比为1∶5时,可溶性有机物去除效果最佳,达到87.8%。

关键词： Waste activated sludge   In pipe thermal pretreatment   High-solid AnMBR   Membrane filtration   Mass balance  

摘要： An integrated system combining in pipe thermal pretreatment with a high-solid anaerobic membrane bioreactor (AnMBR) was developed to promote the anaerobic digestion of waste activated sludge (WAS). Two different pretreatment methods investigated were the venturi nozzle treatment (VNT) and steam injector treatment (SIT), both at a low temperature of 70 degrees C. The biogas production after pretreatment was 23.5-30.5% higher than that of untreated WAS, and the VS based biogas yield was 0.46-0.47 L/g-VS when HRT was 15 days. The membrane operated smoothly when the average flux was 9.6 and 4.5 L/m(2)/h under an MLTS of 25 and 30 g/L, respectively. The calculations of the mass balance indicated that 44-45% COD was converted to methane with pretreatment and only 1% remained in the permeate. That is, high energy recovery and organic matter removal efficiency were achieved for the treatment of WAS using the high-solid AnMBR with in pipe thermal pretreatment.

关键词： Biosurfactants   Fed-batch bioreactor   Waste cooking oil   Antibacterial   Surface tension  

摘要： Biosurfactants are non-toxic, surface-active biomolecules capable of reducing surface tension (ST) and emulsifying interface at a comparably lower concentration than commercial surfactants. Yet, poor yield, costlier substrates, and complex cultivation processes limit their commercial applications. This study focuses on producing biosurfactants by Pseudomonas aeruginosa P7815 in batch and fed-batch bioreactor systems using waste cooking oil (WCO) as the sole carbon source. The batch study showed a 92% of WCO biodegradation ability of P. aeruginosa producing 11 g L-1 of biosurfactant. To enhance this biosurfactant production, a fed-batch oil feeding strategy was opted to extend the stationary phase of the bacterium and minimize the effects of substrate deprivation. An enhanced biosurfactant production of 16 g L-1 (i.e. 1.5 times of batch study) was achieved at a feed rate of 5.7 g L(-1)d(-1) with almost 94% of WCO biodegradation activity. The biosurfactant was characterized as rhamnolipid using Fourier transform infrared spectroscopy (FTIR), and its interfacial characterization showed ST reduction to 29 +/- 1 mN m(-1) and effective emulsification stability at pH value of 4, temperature up to 40 degrees C and salinity up to 40 g L-1. The biosurfactant exhibited antibacterial activity with minimum inhibitory concentration (MIC) values of 100 mu g mL(-1) and 150 mu g mL(-1) for pathogenic E. hirae and E. coli, respectively. These findings suggest that biodegradation of WCO by P. aeruginosa in a fed-batch cultivation strategy is a potential alternative for the economical production of biosurfactants, which can be further explored for biomedical, cosmetics, and oil washing/recovery applications.

关键词： ASM1   Landfill   Leachate treatment   MBR   Modeling  

摘要： Leachate treatment is crucial in landfill management. As landfill ages, inert constituents and ammonia nitrogen concentration in leachate increases, which results in a decrease in biological treatability. In this study, a full-scale MBR treating leachate was dynamically modeled using ASM1. The investigated landfill has been serving for more than 25 years;thus, a decrease in biodegradable organic content and an increase in nitrogen content of the leachate is expected in the years ahead. The calibrated model predicted MLSS, effluent COD, and effluent TN concentrations with high accuracy. Following the calibration study, it was found that soluble inert COD and soluble inert organic nitrogen fractions were the primary reasons of high COD and TKN concentrations in the effluent, respectively. The validated model of the full-scale MBR system treating leachate can be a useful tool to understand the limitations of the system. Soluble inert constituents of the leachate that pass through the membrane necessiate additional treatment processes for discharge into surface water bodies.

关键词： Pharmaceutical compounds   Lipid regulators   Biodegradation   Adsorption   Kinetics  

摘要： Pharmaceutical compounds are emerging pollutants found in the wastewater, which have recently drawn general concerns due to their potential to affect the quality of water bodies, ecosystems, and human health. The purpose of this paper was to assess the removal mechanisms sorption and biodegradation of two lipid regulator pharmaceutical compounds, clofibric acid (CLA) and gemfibrozil (GFZ), through batch experiments using activated sludge obtained from a membrane bioreactor (MBR). As a result, biodegradation was the main removal mechanism in activated sludge for both pharmaceutical compounds, followed by sorption and desorption. The highest removals of CLA and GFZ were 72 and 97%, respectively. According to results from the adsorption test, the CLA and GFZ have a strong adsorption capacity on inactivated biomass. The solid-water distribution coefficient (K-d) for CLA was 8.5 L.g(-1) and for GFZ was 0.75 L.g(-1). The value for Monod constants q was 0.6 h(-1) for both pharmaceutical compounds. The affinity constant K-s value of CLA (4.37 mu g L-1) was higher than the K-s value of GFZ (0.35 mu g.L-1). COD and NH4-N removals were 99 and 97%, respectively, during the kinetic test.

关键词： Bioreactor   Metabolic Symbiosis Disruptor   Metabolic intervention   Metal-organic-framework   Starvation   Microorganism-based therapy  

摘要： Metabolically heterogeneous tumors could rely on "metabolic symbiosis" to mutually regulate the access to extracellular nutrients between glycolytic and oxygenated tumor cells for impeding the development of therapies which aim at metabolic vulnerabilities. Herein, a yeast@MOF bioreactor has been designed as a tumor metabolic symbiosis disruptor to deprive the energy supply of both glycolytic and oxygenated tumor cells for the potent inhibition of metabolically heterogeneous tumors. The yeast@MOF bioreactor integrated the biocompatible probiotic yeast with functional enzyme-encapsulated metal-organic-framework. The bioreactors could competitively consume glucose to reduce their diffusion to glycolytic tumor cells and cut down the tumorous lactate pool. Meanwhile, they could decompose lactate to prevent their exploitation by oxygenated tumor cells. Moreover, the bioreactor could elevate oxidative stress for further amplifying the tumor inhibition effect. We anticipate that this study will not only promote the design of living bioma-terials-based therapy, but also facilitate the development of metabolic interventions-based cancer therapy. (c) 2021 Elsevier Ltd. All rights reserved.

关键词： Bioprocess engineering   ClearColi   Endotoxin-free Escherichia coli   Process conditions   Upstream   Recombinant protein  

摘要： Several studies have searched for new antigens to produce pneumococcal vaccines that are more effective and could provide broader coverage, given the great number of serotypes causing pneumococcal diseases. One of the promising subunit vaccine candidates is untagged recombinant pneumococcal surface protein A (PspA4Pro), obtainable in high quantities using recombinant Escherichia coli as a microbial factory. However, lipopolysaccharides (LPS) present in E. coli cell extracts must be removed, in order to obtain the target protein at the required purity, which makes the downstream process more complex and expensive. Endotoxin-free E. coli strains, which synthesize a nontoxic mutant LPS, may offer a cost-effective alternative way to produce recombinant proteins for application as therapeutics. This paper presents an investigation of PspA4Pro production employing the endotoxin-free recombinant strain ClearColi (R) BL21(DE3) with different media (defined, auto-induction, and other complex media), temperatures (27, 32, and 37 degrees C), and inducers. In comparison to conventional E. coli cells in a defined medium, ClearColi presented similar PspA4Pro yields, with lower productivities. Complex medium formulations supplemented with salts favored PspA4Pro yields, titers, and ClearColi growth rates. Induction with isopropyl-beta-D-thiogalactopyranoside (0.5 mM) and lactose (2.5 g/L) together in a defined medium at 32 degrees C, which appeared to be a promising cultivation strategy, was reproduced in 5 L bioreactor culture, leading to a yield of 146.0 mg PspA4Pro/g dry cell weight. After purification, the cell extract generated from ClearColi led to 98% purity PspA4Pro, which maintained secondary structure and biological function. ClearColi is a potential host for industrial recombinant protein production.

关键词： Cell culture   Induced pluripotent stem cells   Monocytes and macrophages   Myelopoiesis   Stem-cell biotechnology   Life Sciences   general   Biological Techniques   Analytical Chemistry   Microarrays   Computational Biology/Bioinformatics   Organic Chemistry  

摘要： Macrophages derived from human induced pluripotent stem cells (iPSCs) have the potential to enable the development of cell-based therapies for numerous disease conditions. We here provide a detailed protocol for the mass production of iPSC-derived macrophages (iPSC-Mac) in scalable suspension culture on an orbital shaker or in stirred-tank bioreactors (STBRs). This strategy is straightforward, robust and characterized by the differentiation of primed iPSC aggregates into 'myeloid-cell-forming-complex' intermediates by means of a minimal cytokine cocktail. In contrast to the 'batch-like differentiation approaches' established for other iPSC-derived lineages, myeloid-cell-forming-complex-intermediates are stably maintained in suspension culture and continuously generate functional and highly pure iPSC-Mac. Employing a culture volume of 120 ml in the STBR platform, similar to 1-4 x 10(7) iPSC-Mac can be harvested at weekly intervals for several months. The STBR technology allows for real-time monitoring of crucial process parameters such as biomass, pH, dissolved oxygen, and nutrition levels;the system also promotes systematic process development, optimization and linear upscaling. The process duration, from the expansion of iPSC until the first iPSC-Mac harvest, is 28 d. Successful application of the protocol requires expertise in pluripotent stem cell culture, differentiation and analytical methods, such as flow cytometry. Fundamental know-how in biotechnology is also advantageous to run the process in the STBR platform. The continuous, scalable production of well-defined iPSC-Mac populations is highly relevant to various fields, ranging from developmental biology, immunology and cell therapies to industrial applications for drug safety and discovery.