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关键词： 杂交瘤细胞   单克隆抗体   生物反应器   中空纤维  

摘要： 单克隆抗体在生物学和医学研究领域中显示了极大的应用价值,是免疫检验中的新型试剂,是生物治疗的导向武器。作为医学检验试剂,单克隆抗体可以充分发挥其优势,如特异性好,灵敏度高,更便于质量控制,利于标准化和规范化。传统的方法是利用小鼠腹水制备单克隆抗体,但是近几十年杂交瘤细胞体外大规模培养制备单克隆抗体技术也在不断发展。特别是单克隆抗体在疾病诊断和治疗方面的需求,更进一步促进了杂交瘤细胞体外培养生产技术的发展,体外培养杂交瘤细胞生产的单克隆抗体已应用到许多方面。由于杂交瘤细胞的半贴壁性质,无论是悬浮培养还是贴壁培养,均可进行杂交瘤细胞的体外大规模培养。针对应用于体外诊断试剂的杂交瘤细胞体外培养制备单克隆抗体进行综述,主要包括中空纤维细胞培养和生物反应器细胞培养方法,以及不同培养方法优化的进展。

关键词： BIOREACTORS   CELL lines   MYCELIUM   STEM cells   PERFUSION   THERAPEUTIC use  

摘要： Although the scalability of stainless steel bioreactors has been investigated for more than 50 years, and many methods for the characterization of these bioreactors have been evolved, the investigation of scalability of single-use bioreactors (SUBs) contains several new challenges. SUBs permit a versatile design that is not necessarily oriented towards classical geometric conditions and allows a wide variety of mixing principles. Among the various principles might be some advantageous for the cultivation of particular types of shear sensitive cells, such as mycelium-forming organisms and stem cells. In addition, these systems must be applicable in emerging fields like continuous perfusion *** this paper, we will discuss the current state of disposable bioreactors in terms of cultivation performances, with a special emphasis on the impact of physiological properties of cells across several scales and cultivation modes beyond classical engineering parameters.

关键词： Dynamic membrane   Anammox   Mesh filtration   Denitrification   PCR sequence analysis  

摘要： This study investigated a novel bioreactor configuration coupled with a side-stream dynamic membrane (DM) for Anammox enrichment as an alternative for conventional membrane. Bioreactor was fed with synthetic feed and seeded with a mix of anaerobic and aerobic sludge. In situ mechanical cleaning was employed for DM cleaning. DM development and performance was analysed over two polyamide-nylon meshes (200 and 52 mu m). Solid-liquid separation of 52 mu m mesh outperformed 200 mu m with an average effluent turbidity of 2.4 +/- 0.1 NTU. The system was operated at a maximum nitrogen loading rate of 696mg-NL-1 d(-1) and achieved a maximum nitrogen removal rate of 611.6 mg-NL(-1)d-(1). At steady state, the average ammonium, nitrite and total nitrogen removal efficiencies were 87 +/- 0.6%, 98.5 +/- 0.15% and 87.5 +/- 0.56% respectively. Digital realtime PCR Sequence analysis showed that Planctomycetales belonging to ascertained Anammox-specific genera progressively increased their presence in the reactor consistently with its nitrogen removal performance.

关键词： essential oil   souring   bioreactor   Sulfate-reducing bacteria  

摘要： Biocide injections are used for controlling biological souring in mature oil wells, but unpredictable results of such practices are also frequently reported. To address this problem, this research aimed to quantify the effect of four new biocides, and one commonly used biocide, within a dynamic system (packed-bed bioreactor) without using batch testing. The bioreactor was operated for 591 days, and the results showed that sulfate-reducing-bacteria (SRB) activity could recover within a period that varied from 15 to 60 days. Neem-oil (NO) (1.5% vol/vol) and 3,5-dimethyl-1,3,5-thiadiazinane-2-thione (Dazomet, DZ) (0.5% vol/vol) were the most efficient in controlling SRB activity. The tests showed that the mechanistic interaction controlling souring is not only associated with the compounds' toxicity. Immiscible biocides not only killed cells, but they also can control SRB-recovery rates after the injection of biocides.

关键词： Recycle membrane bioreactor   Dextransucrase   Dextranase   Oligodextrans   Molecular weight   Kinetics  

摘要： A continuous synthesis process for the production of oligodextrans from sucrose by using dextransucrase and dextranase in a recycle ultrafiltration membrane bioreactor was developed. During continuous oligodextrans synthesis, changes in weight-average molecular weight (Mw) and polydispersity index (D value) in the second feed tank (i) were monitored by high-performance gel permeation chromatography. Mw decreased with increasing reaction time, resulting in an increasingly homologous solution of low Mw oligodextrans (approximately 1 x 10(4) Da). The D value of the oligodextrans produced was nearly 1.0. In addition, the polymer degradation model well described the kinetics of Mw changes in oligodextrans. Results showed that recycle membrane bioreactor coupled with dextransucrase and dextranase is a simple and effective method that can be used to produce and improve the quality of oligodextrans.

关键词： angiogenesis   bioengineering   cell therapy   stem cells   tissue engineering   transplantation   vascularised chamber  

摘要： Vascularisation is key to developing large transplantable tissue constructs capable of providing therapeutic benefits. The vascularised tissue engineering chamber originates from surgical concepts in tissue prefabrication and micro-surgery. It serves as an in vivo bioreactor in the form of a closed, protected space surgically created and embedded within the body by fitting a non-collapsible chamber around major blood vessels. This creates a highly angiogenic environment which facilitates the engraftment and survival of transplanted cells and tissue constructs. This article outlines the chamber concept and explores its application in the context of recent advances in biomedical engineering, and how this can play a role in the future of cell therapies and regenerative medicine.

关键词： C. carboxidivorans   Continuous syngas fermentation   Carbon monoxide   Acidogenesis and solventogenesis   Stirred-tank bioreactors in series  

摘要： Microbial batch production of alcohols by fermentation of CO-rich gases with Clostridia is limited by low volumetric productivities due to the need for formation of organic acids first (acidogenic phase) followed by re-consumption of the acids to form alcohols (solventogenic phase). Continuous autotrophic production of alcohols was made possible with C. carboxidivorans by use of two continuously operated stirred-tank bioreactors in series without cell retention. The pH in the first reactor was controlled to pH 6.0 for continuous growth of the cells. Steady-state concentrations of 3.0 g L-1 acetate and 0.1 g L-1 butyrate were measured at a mean hydraulic residence time of 8.3 h. The pH in the second reactor was controlled to pH 5.0 for enhancing continuous formation of alcohols resulting in steady-state concentrations of 6.1 g L-1 ethanol, 0.7 g L-1 butanol, and 0.1 g L-1 hexanol at a mean hydraulic residence time of 12.5 h. Continuous formation of alcohols from CO was already observed in the first stirred-tank reactor parallel to the formation of acids, whereas re-consumption of acids as well as de-novo syntheses of alcohols from CO was shown in the second stirred-tank reactor. Thus, high final alcohol- to-acid ratios of 3.9 g(ethanol) g(acetate)(-1) and 4.4 g(butanol) g(butyrate)(-1) were achieved in the continuous syngas-fermentation process with C. carboxidivorans.

关键词： Benzene   MALDI-TOF MS/MS   Proteomics   FT-IR   CPBBR   Docking  

摘要： The present study reveals the benzene degrading potential of bacterial species isolated from petroleum contaminated soil. Genomic analysis suggests that Bacillus sp. M4 was found to be dominating species. The process parameters were optimized and found to be pH 7.0 +/- 0.2, temperature 32 +/- 5 degrees C, immobilization time (20 days) and benzene concentration 400 mg/L. The maximum removal efficiency of benzene was calculated and found to be 93.13% at elimination capacity 156 (mg/L/day) and inlet loading rate 192 (mg/L/day) achieved in 54th days of operation. In the study, the residual metabolites were analyzed by GC/MS analysis and identified as benzene-1, 2-diol. In order to identify the responsible protein involved in the process of benzene biodegradation The proteomic study was performed and proteins were identified by MALDI-TOF analysis. The molecular docking was confirmed by the benzene biodegradation.

关键词： Bacterial community dynamics   454 pyrosequencing   Osmotic membrane bioreactor   Salt inhibition   Nitrification  

摘要： The objective of this study was to evaluate the effects of salt accumulation on nitrifying bacterial communities in a nitrifying bioreactor combined with forward osmosis. The conversion of nitrite to nitrate was inhibited at a total dissolved solids (TDS) concentration of 17.3 g/L, whereas conversion of ammonia to nitrite was inhibited at a higher concentration (52.8 g-TDS/L). The gene copies of ammonia-oxidizing bacteria (AOB) were more abundant than those of nitrite-oxidizing bacteria (NOB) throughout the entire operating period of 225 days. Among NOB, the number of copies of Nitrobacter spp. were 100-1000 times higher than those of Nitrospira spp. A total of 140 operational taxonomic units were identified using 454 pyrosequencing. The relative abundances of autotrophic AOB and NOB accounted for 34.1-57.8% during 225 days. Dominance of Nitrosomonas eutropha was stable as a salt-tolerant AOB, but the representative NOB, Nitrobacter winogradskyi, showed salt-sensitive variations in their relative abundance. Nonmetric multidimensional scaling and hierarchical clustering analysis clearly illustrated the shift in bacterial community due to external conditions, i.e., ammonia loading rate, alkalinity availability, and salinity. Heterotrophic bacteria contributed to changes in overall bacterial community structure in the nitrifying osmotic membrane bioreactor despite the absence of carbon sources in the influent.