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关键词： 生物反应器   动物细胞培养   兽用疫苗  

摘要： 由于我国兽用疫苗市场的飞速成长,兽用疫苗的生产工艺正在经历着深刻的技术创新。用于动物细胞培养和疫苗制备的工艺在过去会呈现出耗时且费力的特征,现今正朝着生物反应器技术的应用发展。动物细胞培养和疫苗制备过程已被转化。在生物反应器中大规模培养动物细胞是将生物技术转化为产品的关键,并且它是兽用疫苗生产过程的中心。基于此,文章进行了相关的探讨,本文主要介绍了使用生物反应器技术进行动物细胞培养的优势,并简要讨论了该技术在兽用疫苗生产中的应用。

关键词： 生物反应器   氧化   热解   吸附   联合治理   挥发性有机化合物  

摘要： 考虑到挥发性有机物(VOCs)治理技术的复杂性以及实际工程应用中的经济效益,生物联合治理技术成为了一种研究趋势。本文阐述了目前主要的生物联合治理技术,包括紫外光降解技术-生物法、低温等离子体技术-生物法、化学-生物法、吸附-生物法、燃烧-生物法以及生物法组合工艺。总结了生物联合治理技术的研究进展与存在的问题。紫外光、低温等离子体技术以及化学法常作为预处理技术与生物进行联合应用,在提高整体降解效果的同时也会使生物反应器具有更好的运行性能。吸附法、燃烧法通常作为末端处理技术与生物法进行联合治理,以保障废气可以达标排放。生物组合技术也通过将不同生物治理技术相结合形成协同优势使其对于工业废气取得更优的降解效果。文中指出了生物联合技术在废气治理方面是一个有前景的选择,但生物联合治理技术的研究还不够深入,实际应用也不够成熟,因而需要进行进一步的探究。

关键词： 体内生物反应器   骨组织工程   血管化   预构  

摘要： 目的对用于骨组织工程的体内生物反应器(in vivo bioreactor,IVB)的研究进展进行综述,为后续研究提供参考。方法查阅近年来骨组织工程IVB相关文献,从IVB构建原则、构建IVB的组织类型、部位及方法,以及IVB用于构建组织工程骨的优劣等方面进行综述。结果 IVB是利用机体自我再生能力,把身体作为生物反应器在损伤部位或能够支持新组织再生的异位部位再生新组织或器官。IVB可由组织瓣(皮下袋、肌瓣/袋、筋膜瓣、骨膜瓣、大网膜瓣/腹腔)和轴向血管蒂(轴向血管束、动静脉环)单独或联合构建。使用IVB能预构与骨缺损形状、大小匹配的血管化组织工程骨。预构的骨组织可作为游离骨移植物、带蒂骨瓣或游离骨瓣修复骨缺损。IVB解决了传统骨组织工程血管化不足的问题。结论 IVB是一种有临床应用前景的血管化组织工程骨预构和骨缺损修复重建的方法,在修复大型复杂骨缺损方面有着独特优势。但因IVB存在构建复杂以及手术并发症等问题影响了其临床应用,后续需致力于开发一种简单、安全、高效的IVB。

关键词： 虾肉   生物反应器   实验室培养   华氏度   极微小   点心   美味   新加坡  

摘要： 在新加坡一个工业区的角落里,通过虾极微小的细胞样本培养出来的真实虾肉,正在精确加热至82华氏度(约27.78摄氏度)的生物反应器里稳定地生长着。

关键词： 细分领域   pH传感器   生物反应器   生物制药   蛋白类药物   工艺开发   哺乳动物细胞   类型统计  

摘要： pH传感器成为生物反应器上必不可少的过程分析类传感器——在工艺开发或生产中,使用人员该如何选择pH传感器,以获得最佳的使用体验呢?全球生物制药市场规模逐年增长,蛋白类药物和疫苗成为主要细分领域。整个生物制药加工过程中,生物反应器是上游生产的核心设备。按照培养的细胞类型统计,75%的生物反应器用于培养哺乳动物细胞。

关键词： 厌氧氨氧化   基质浓度   水力停留时间   颗粒污泥   性能强化  

摘要： 采用提高基质浓度和缩短水力停留时间两种氮负荷提升方式运行UASB厌氧氨氧化反应器,比较了两种方式对反应器运行性能的影响。试验结果表明,经过300 d的连续运行,对NH_(4)^(+)-N、NO_(2)^(-)-N、TN的去除率分别为93.09%、95.26%和88.46%,氮容积去除负荷由0.75 kg/(m^(3)·d)升至2.26 kg/(m^(3)·d)。稳定阶段的化学计量关系ΔNO_(2)^(-)-N/ΔNH_(4)^(+)-N和ΔNO_(3)^(-)-N/ΔNH_(4)^(+)-N分别为1.12和0.14,接近理论值,第Ⅲ阶段出水pH值逐渐升高最后趋于稳定,产气量达到1.51 L/(L·d),污泥粒径增至5.0~7.0 mm,沉速提高至(8.94±0.77)cm/s,颗粒化程度高、颜色鲜红,脱氮性能得到强化。相比提高基质浓度,采用低浓度进水并缩短水力停留时间的方式提升氮负荷,能避免基质自身的抑制作用,稳定且较快地强化厌氧氨氧化反应器性能,有利于颗粒污泥的形成。

关键词： Membrane bioreactor   Polluted surface water   Unknown screening   Molecular characterization   Orbitrap mass spectrometry  

摘要： The increasing organic contamination of surface water hinders the conventional tap water treatment process. Membrane bioreactors (MBRs) are a promising alternative technology for recovering water from polluted surface water. In this study, the composition changes of dissolved organic matters (DOMs) in MBR and ultraviolet/ozone (UV/O-3)-MBR systems for polluted surface water treatment were investigated using Orbitrap mass spectrometry analysis with unknown screening. The intense DOM ions within a mass-to-charge ratio range of 100-500 was detected, and 2340 molecular formulae from 5743 peaks were assigned to the two systems. The most abundant components were formulae with C, H, O, N, and CHO only classes. The highest formulae decrease including CHO, CHON, CHOS, and CHONS were attributed to the bio-carrier used in both systems. Results showed that bioprocess was the main contributor in the DOM reduction, and the integration of UV/O-3 into the MBR improved the DOM composition changes. Biodegradable components with low O/C ratio in the CHO and CHON classes remarkably increased in the UV/O-3-MBR system. The integration of UV/O-3 as a polishing step in the recirculation stream of MBR system was effective in improve the DOM removal. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Dynamic membrane bioreactor   Biofilm removability   Wastewater treatment   Extracellular polymeric substance   Microbial community  

摘要： Dynamic membrane bioreactors mainly rely on the in-situ formed biofilms on support materials to reject fine particles in water. The development of irremovable biofilms on support materials can decrease the cleaning efficiency when removing the unwanted biofilms with low permeability by water flushing. In the present study, the initial formed biofilms on support materials at 5-day solids retention time (SRT) were removable by water flushing. After repeated cleaning with off-line water flushing during operation, however, irremovable biofilms were developed gradually inside the mesh pores and thus, rapid rising in transmembrane pressure occurred in every one to three days. At 20-day SRT, the biofilms formed on support materials with the same operation time were still removable. Therefore, both low SRT and repeated water flushing promoted the formation of irremovable biofilms on support materials. Further study found that the composition and microbial community between the irremovable and removable biofilms were significantly different, which differentiated the biofilm adhesion and removability. The irremovable biofilms had a greater faction of proteins (49.0%) and beta-D-glucopyranose polysaccharides (17.8%) in extracellular polymeric substance (EPS), while the removable biofilms had a greater fraction of alpha-D-glucopyranose polysaccharides. After repeated cleaning with off-line water flushing during operation, Nitrospiraceae was selectively enriched in the irremovable biofilms at a relative abundance of 39.1%, which could have resulted in the particular EPS matrix that strengthened the biofilm adhesion. (C) 2021 Elsevier Ltd. All rights reserved.

关键词： Fixed-bed reactor   Recombinant yeast   Xylose utilization   Hemicellulose hydrolysate   2G ethanol   Continuous fermentation   Inhibitors  

摘要： Development of a robust and competitive process for second generation (2G) ethanol production requires efficient fermentation of both glucose and xylose fractions generated after biomass pretreatment and saccharification, using industrial media containing high sugars concentration and inhibitors, under prolonged exposure to high ethanol titers. Thus, it is important to study the influence of these industrial operation conditions on yeast fermentation performance, which has been little addressed in the literature. In this work we evaluated the steady-state stability of continuous 2G ethanol production from xylose in a fixed bed reactor. The bioreactor was packed with recombinant, xylose-utilizing Saccharomyces cerevisiae cells entrapped in calcium alginate and it was operated with different inlet xylose concentrations and dilution rates. Medium supplementation with nutrients and scheduled washing steps were effective in maintaining high xylose conversion levels during continuous fermentation for more than 15 days with an ethanol productivity of 5.0 g/L.h. Effects of prolonged exposure to ethanol and inhibitors present in undetoxified hydrolysate were further investigated in repeated batches. Overall, the results show that improved ethanol tolerance in recombinant yeasts and innovative solutions to increase sugar concentration in the hydrolysates are the main challenges to achieve a feasible industrial process for 2 G ethanol production.

关键词： bioreactor   blood   design of experiments   erythrocyte   in vitro cell culture  

摘要： The aim of this study was to develop a robust, quality controlled, and reproducible erythroid culture system to obtain high numbers of mature erythroblasts and red blood cells (RBCs). This was achieved using a fully controlled stirred-tank bioreactor by the design of experiments (DOE) methods in the serum-free medium by defining the appropriate culture parameters. Human cord blood CD34+ cells were first cultured in static flasks and then inoculated to stirred-tank bioreactors. Cell diameter was gradually decreased and final RBC yields were significantly higher when cells were inoculated at sizes smaller than 12 mu m. The larger immature cells in the basophilic stage did not survive, while smaller mature erythroid cells were successfully expanded at high agitation speeds, demonstrating that appropriate seeding timing is critical. A high inoculation cell density of 5 x 10(6) cells/ml was achieved reaching 1.5 x 10(7) cells/ml. By using DOE analysis fitted to precise stages of erythropoiesis, we were able to acquire the optimal culture parameters for pH (7.5), temperature (37 degrees C), dissolved oxygen, agitation speed (500 rpm), inoculation timing (cell diameter 12-13 mu m), media feeding regimen, and cell seeding density (5 x 10(6) cells/ml). The final pure RBCs showed appropriate functions compared with fresh donor RBCs, confirming that manufacturing mature RBCs with reproducibility is possible.