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关键词： 人工湿地   氧化石墨烯  

摘要： 本研究探讨了氧化石墨烯的暴露下人工湿地基质酶(脱氢酶、脲酶、磷酸酶)活性的变化情况,以及对植物抗氧化酶系产生的影响,揭示了氧化石墨烯对人工湿地基质酶活性和植物的潜在影响。

关键词： 光催化   正渗透膜生物反应器   染料废水  

摘要： 以氯化钠为汲取液,TiO_(2)-紫外光催化技术和正渗透膜生物反应器(FOMBR)协同处理模拟染料废水,研究其对水中污染物的去除率及膜面污染物的分布。结果表明,该反应器缓解了传统FOMBR的通量骤降问题,并保持了较好的有机物去除水平。水通量从5.82 L/(m^(2)·h)缓慢下降至4.39 L/(m^(2)·h);对废水中的COD、总氮、总磷及氨氮的平均去除率分别为99.94%,97.06%,99.54%和97.59%;汲取液中甲基橙平均脱色率为96.70%,总苯胺截留率达85.19%。膜面污染物集中分布在0~38μm,且均随扫描层数的增加呈现出先增后减的趋势,主要污染物为蛋白质和α-D-吡喃多糖,平均荧光强度分别为36.74和44.92。

关键词： 生物反应器   搅拌桨   数值分析   湍流模型  

摘要： 小型生物反应器是实验室常用的反应设备,不同倾斜角度的涡轮直叶搅拌桨对反应器的性能有重要影响。采用CFD数值分析方法中k-ε湍流模型,对不同倾斜角度条件下涡轮直叶搅拌桨的小型生物反应器的流场流型进行模拟分析,对比结果表明:在速度云图的分析上搅拌桨倾斜夹角小于70°的桨叶对液体的带动效果较好,在剪切速率分析结果中,搅拌桨倾斜夹角(α)绝对值在50°~70°时,剪切速率偏高。并通过物质传递和湍流动能分析比较出下吸式安装比上排式安装的桨叶搅拌效果好,倾斜夹角为-45°时搅拌效果最佳。

关键词： perfusion bioreactor   vascular graft   electrospinning   nanotopography   scaffold architecture  

摘要： Access to lab-grown fully functional blood vessels would provide an invaluable resource to vascular medicine. The complex architecture and cellular makeup of native vessels, however, makes this extremely challenging to reproduce in vitro. Bioreactor systems have helped advanced research in this area by replicating many of the physiological conditions necessary for full-scale tissue growth outside of the body. A key element underpinning these technologies are 3D vascular graft templates which serve as temporary scaffolds to direct cell growth into similar cellular architectures observed in native vessels. Grafts further engineered with appropriate physical cues to accommodate the multiple cell types that reside within native vessels may help improve the production efficiency and physiological accuracy of bioreactor-grown vessel substitutes. Here, we engineered two distinct scaffold architectures into an electrospun vascular graft aiming to encourage the spatial organisation of human vascular endothelial cells (hCAECs) in a continuous luminal monolayer, co-cultured with human fibroblasts (hFBs) populating the graft wall. Using an electrospun composite of polycaprolactone and gelatin, we evaluated physical parameters including fibre diameter, fibre alignment, and porosity, that best mimicked the spatial composition and growth of hCAECs and hFBs in native vessels. Upon identifying the optimal scaffold architectures for each cell type, we constructed a custom-designed mandrel that combined these distinct architectures into a single vascular graft during a single electrospinning processing run. When connected to a perfusion bioreactor system, the dual architecture graft spatially oriented hCAECs and hFBs into the graft wall and lumen, respectively, directly from circulation. This biomimetic cell organisation was consistent with positive graft remodelling with significant collagen deposition in the graft wall. These findings demonstrate the influence of architectural cues

摘要： 酸性成纤维细胞生长因子FGF1作为FGF家族的重要成员，在胚胎发育、伤口修复、骨再生与神经保护等方面具有广泛生物学活性，具有显著的临床应用价值，而传统获取方式和目前的基因工程生产方法远不能满足临床需求。生物反应器是规模化生产高附加值药用重组蛋白的常规方法。与传统的微生物和动物生物反应器相比，植物生物反应器具有易规模化、效率高、成本低等多方面的特殊优势。本文在简介FGF家族不同因子的基础上，重点对FGF1基本结构、生物学功能进行了概述，收集整理了近期不同生物反应器生产FGF1的进展情况，尤其是利用植物细胞表达平台表达FGF1的情况，展望了植物生物反应器在合成生物领域的发展潜力和广阔的市场前景，希望能对拓宽植物生物反应器的理论研究和产业化应用起到明显的推动作用，加快其市场化普及推广。

关键词： 厌氧氨氧化   活性恢复   基质浓度   膜生物反应器   生物滤柱  

摘要： 为研究如何快速恢复在突发状况下长期断流的厌氧氨氧化工艺的活性,比较分析了 3个厌氧氨氧化反应器的脱氮性能及微生物种群变化.分别为R1(生物滤柱)、R2(膜生物反应器,MBR)、R3(MBR),其中R1与R2进水基质浓度相同,R2与R3反应器形式相同,进水基质浓度不同.结果表明:R1、R2、R3中的厌氧氨氧化污泥分别经过39d、93d、76d得到恢复,总氮去除率分别恢复至87.0％、83.4％、87.6％,总氮去除负荷分别恢复至0.359,0.114,0.244kg/(m3·d).R1与R2相比,厌氧氨氧化生物滤柱能够承受较高的水力负荷,长期断流后具有较高的稳定性,且更容易恢复.R2与R3相比,在进水基质浓度较高的条件下,厌氧氨氧化菌具有充足的营养底物,且高基质水平形成的底物浓度压力更有利于提升氨氮与亚硝酸盐氮在污泥内部的传质效果,恢复效果更好.高通量测序结果表明,3个反应器在恢复前(后)CandidatusKuenenia的相对丰度分别为17.3％(32.0％)、1.6％(2.6％)、1.8％(6.0％),恢复后R1中相对丰度最高.

摘要： 研究了长期暴露条件下磺胺甲恶唑（SMX）对序批式生物反应器（SBR）脱氮性能及微生物群落的影响。结果表明，长期暴露于6 mg/L的SMX环境中，SBR对有机物和NH;-N的去除效果没有明显变化。COD的平均去除率为92.57%±0.92%，NH;-N的平均去除率达到98.71%±0.34%。NO;-N和NO;-N的出水浓度随运行时间的增加而升高。在第104 d时比耗氧速率（SOUR）、比氨氧化速率（SAOR）、比亚硝酸盐氧化速率（SNOR）、比硝酸盐还原速率（SNRR）和比亚硝酸盐还原速率（SNIRR）较添加SMX前下降了23.33%、24.47%、28.29%、14.97%和15.81%。SMX的存在致使胞外聚合物（EPS）、松散型胞外聚合物（LB-EPS）和紧密型胞外聚合物（TB-EPS）及其中的蛋白质（PN）和多糖（PS）含量随运行时间的增长而增加，PN/PS呈上升趋势。活性氧（ROS）的生成量和乳酸脱氢酶（LDH）的释放量随运行时间的增长而增加。6 mg/L的SMX使活性污泥微生物群落的丰富度降低，多样性升高，降低了变形菌门（Proteobacteria）、绿弯菌门（Chloroflexi）和γ-变形菌纲（Gammaproteobacteria）的相对丰度，从而影响了SBR的脱氮性能。

关键词： Anaerobic membrane bioreactor (AnMBR)   Membrane fouling   Membrane rejection   Upflow anaerobic sludge blanket   Dissolved organic matter   Techno-economic analysis  

摘要： This research investigated the impact of permeate flux and gas sparging rate on membrane permeability, dissolved and colloidal organic matter (DCOM) rejection and process economics of granular anaerobic membrane bioreactors (AnMBRs). The goal of the study was to understand how membrane fouling control strategies influence granular AnMBR economics. To this end, short-and long-term filtration tests were performed under different permeate flux and specific gas demand (SGD) conditions. The results showed that flux and SGD conditions had a direct impact on membrane fouling. At normalised fluxes (J(20)) of 4.4 and 8.7 L m(-2) h(-1) (LMH) the most favourable SGD condition was 0.5 m(3) m(-2) h(-1), whereas at J(20) of 13.0 and 16.7 LMH the most favourable SGD condition was 1.0 m(3) m(-2) h(-1). The flux and the SGD did not have a direct impact on DCOM rejection, with values ranging between 31 and 44%. The three-dimensional excitation-emission matrix fluorescence (3DEEM) spectra showed that protein-like fluorophores were predominant in mixed liquor and permeate samples (67-79%) and were retained by the membrane (39-50%). This suggests that protein-like fluorophores could be an important foulant for these systems. The economic analysis showed that operating the membranes at moderate fluxes (J(20) = 7.8 LMH) and SGD (0.5 m(3) m(-2) h(-1)) could be the most favourable alternative. Finally, a sensitivity analysis illustrated that electricity and membrane cost were the most sensitive economic parameters, which highlights the importance of reducing SGD requirements and improving membrane permeability to reduce costs of granular AnMBRs.

关键词： 灌流培养   重组CHO细胞   生物反应器   水痘-带状疱疹病毒糖蛋白E  

摘要： 目的采用超声截留控制器超声使得细胞聚集、沉降的方法截留悬浮细胞,优化重组CHO细胞灌流培养工艺。方法基于无血清化学限定(CD)培养基,选择表达水痘-带状疱疹病毒(varicella-zoster virus,VZV)糖蛋白E(VZV gE)的重组CHO细胞在5 L生物反应器中灌流培养。对初步确定的培养条件进行响应面分析,优化培养温度、培养基pH、灌流速度;并采用上述优化条件验证超声截留控制器灌流培养重组CHO细胞工艺。结果本实验条件下,优化后的灌流培养条件为:温度33.2℃、pH 7.0、灌流速度4.1 mL/min。3批验证结果显示,相较批培养,灌流培养时间延长5~7 d,收获体积增加5~7倍。其中,葡萄糖和乳酸含量、细胞密度和活性批间变化趋势一致;细胞截留效率均高于90%,批间差异无统计学意义(P>0.05);目的蛋白比活性约为0.5,批间差异无统计学意义(P>0.05);Western blot结果显示,相对分子质量和糖基化修饰与批培养一致。结论实现了5 L生物反应器灌流培养重组CHO细胞表达gE蛋白工艺,为后续大规模生产提供了依据。