微气泡耦合生物反应器的研究进展

微气泡具有气液接触面积大、气体溶解速率快、上升速度慢和水中停留时间长等理化特征，非常适合于高气液传质效率需求的生物发酵过程。本文介绍了能够耦合生物反应器的几种微气泡发生装置，分别为微气泡分散器、微孔膜、流体振荡器耦合微孔膜和微气泡曝气搅拌桨；并简述了微气泡发生装置耦合搅拌式生物反应器、气升式生物反应器和生物膜反应器在生物反应过程的应用进展；最后回顾了二氧化碳微气泡在生物反应器的应用研究进展。指出微气泡耦合生物反应器的研究仍处于起步阶段，在放大规律和能耗方面仍处于研究空白。微气泡耦合生物反应器的发展对工业生物技术、石油化工、污水处理和资源再利用等的发展具有重要的意义。     

植物细胞培养生物反应器的研究进展

介绍了用于植物细胞培养的搅拌式反应器、非搅拌式反应器、光反应器及固定化反应器等,为植物细胞培养中反应器的选择和设计提供参考     

石油生物脱硫过程和反应器的研究进展

综述了近年来石油生物催化脱硫反应器的研究进展,介绍了搅拌釜反应器、气升式反应器、流化床反应器、固定床反应器等生物脱硫反应器的特点和应用状况,并分析其发展趋势.同时介绍了石油生物脱硫用于工业化的一般过程,提出了当前需要解决的问题并对今后的研究工作进行展望.     

计算流体力学在模拟生化反应器中的应用研究

计算流体力学是生化反应器模拟研究的重要手段，简述了流体力学理论研究概况及其在搅拌式生物反应器，气升式生物反应器中的应用，并指出了进一步研究的方向。     

连续化生产生物柴油的反应器与工艺的研究进展

生物柴油因其具有优良的环境友好性和可再生性日益受到关注。传统的间歇反应器制备生物柴油存在生产效率低、产品质量不稳定等弊端,连续化生产节能减耗、降低成本、产生规模效益成为生物柴油工业化生产的趋势。本文简介了国内外生物柴油的发展,综述了连续搅拌釜式反应器、活塞流反应器、固定床反应器等主要连续化生产生物柴油反应器与工艺,并进行了对比。     

新型连续乳液聚合反应器

介绍了4种主要连续乳液聚合反应器的研究新进展,包括连续搅拌釜式反应器、连续环管式反应器、脉冲填料塔式反应器及库爱特-泰勒旋流式反应器。提出了连续乳液聚合反应器的发展方向。     

搅拌气升式生物反应器的研究进展

搅拌气升式反应器作为一种新型高效的生物反应器,因为其独特的优势而越来越受到重视,具有良好的研究和应用前景.概述了搅拌气升式反应器的国内外研究进展,着重评述了搅拌气升式反应器相比于传统机械搅拌式反应器和气升式反应器的所体现出的优点,详细介绍和分析了该新型反应器的基本结构、流体力学性质及相关的重要表征参数,并对其在生物发酵和化工行业中的应用和发展进行了回顾和展望.     

环己烷催化氧化反应器形式的研究

针对金属卟啉催化氧化环己烷工艺的特点,选择鼓泡式反应器、搅拌式反应器和多釜串联搅拌式反应器进行一系列实验,分析了各类反应器形式对氧化产物的影响,确定了环己烷催化氧化反应器的最佳形式。     

基于介尺度PBM模型的生物反应器放大模拟及实验研究

对于通气搅拌式工业生物反应器的放大设计而言,精确预测气泡尺寸和体积传质系数非常重要,因此需要建立合适的气泡聚并和破碎模型,以保证反应器的高效操作。以5 L通气搅拌式生物反应器为对象,以气泡尺寸和体积传质系数的实验数据为基准,模拟并考察了两种聚并模型和四种破碎模型对生物反应器内流体流动行为以及传质能力的影响。结果表明,基于介尺度理论的修正聚并模型与考虑黏流剪切的破碎模型组合,所得模拟结果与实验数据吻合最好,这为大型生物反应器的桨型优化提供了模型基础。因为工业化生物发酵通常是在大型生物反应器中进行,搅拌桨型对生物反应器效能至关重要,故本研究在选定最优气泡聚并破碎模型的基础上,通过叶轮末端剪切力相等的放大原则将5 L通气搅拌式工业生物反应器放大到400 m³,同时考察了六斜叶圆盘搅拌桨、非对称式抛物线搅拌桨、布鲁马金式搅拌桨以及六直叶圆盘搅拌桨等桨型组合对气泡破碎能力和气体分散效果的影响,并通过综合对比气含率、体积传质系数等参数,得到400 m³通气搅拌式生物反应器的最优桨型组合。     

曝气式反应器中木质素过氧化物酶的合成及对印染废水配制液的脱色处理

比较了黄孢原毛平革菌在3种生物反应器(搅拌式反应器、鼓泡式反应器、曝气式反应器)中合成木质素过氧化物酶(LiP)和锰过氧化物酶(MnP)的差异. 结果表明，曝气式反应器对酶的合成(尤其是LiP)最为有利. 考察了曝气式反应器中半连续培养和连续培养两种方式下酶的合成和橙I脱色情况，发现半连续培养可使培养体系长时间保持较高酶活力，置换比例为1/2时染料废水可连续脱色5批，脱色率达到90%以上，比脱色率在46.7 g/(g×d)以上. 连续培养条件下酶很快失活，废水的脱色率迅速下降. 在曝气式反应器中用半连续培养的方式(置换比例1/2)对实际印染废水进行处理，可处理废水4批，前3批脱色率达到90%以上，第4批有明显下降.     

Animal cell bioreactors — recent advances and challenges to scale-up

The demand for animal cell derived products has stimulated the development of bioreactors in the last decade. Most of those developments allow a higher cell concentration to be achieved in the bioreactor than in the past, primarily by means of the continuous flow of culture medium and a mechanism of cell retention. The advantages and technological challenges of some of these developments are discussed. Lagging behind the bioreactor developments is the strategy for culture operation and optimization. The need for suitable kinetic models to describe animal cell growth is emphasized.     

The Proliferation of Pre-Pubertal Porcine Spermatogonia in Stirred Suspension Bioreactors Is Partially Mediated by the Wnt/β-Catenin Pathway

Male survivors of childhood cancer are at risk of suffering from infertility in adulthood because of gonadotoxic chemotherapies. For adult men, sperm collection and preservation are routine procedures prior to treatment; however, this is not an option for pre-pubertal children. From young boys, a small biopsy may be taken before chemotherapy, and spermatogonia may be propagated in vitro for future transplantation to restore fertility. A robust system that allows for scalable expansion of spermatogonia within a controlled environment is therefore required. Stirred suspension culture has been applied to different types of stem cells but has so far not been explored for spermatogonia. Here, we report that pre-pubertal porcine spermatogonia proliferate more in bioreactor suspension culture, compared with static culture. Interestingly, oxygen tension provides an avenue to modulate spermatogonia status, with culture under 10% oxygen retaining a more undifferentiated state and reducing proliferation in comparison with the conventional approach of culturing under ambient oxygen levels. Spermatogonia grown in bioreactors upregulate the Wnt/ β-catenin pathway, which, along with enhanced gas and nutrient exchange observed in bioreactor culture, may synergistically account for higher spermatogonia proliferation. Therefore, stirred suspension bioreactors provide novel platforms to culture spermatogonia in a scalable manner and with minimal handling.     

An industrial cell biologist's wish list

The current state of protein production by eukaryotic cells in culture is reviewed by a cell biologist with an eye towards areas that could benefit from more work by chemical engineers. The basic question of how the type of bioreactor influences cell productivity has not been answered. We are still learning how to optimize protein production in all types of bioreactors. Recent examples show that optimization can increase productivity over 10-fold. Support work needs to be done to determine the limits of individual cell productivity. Basic cell metabolism work needs to be done in serum-free medium to make it generally applicable. Only then can better bioreactors be designed with useful probes to monitor important substances.     

Growth of Rhizobium leguminosarum on peat in rotating bioreactors

The legume inoculant Rhizobium leguminosarum was grown on peat in roller bottles and a rotating drum bioreactor. Growth conditions were first determined using experiments in roller bottles. The best growth rate and cell count were obtained with peat containing 40% moisture (wet basis) and a volume fraction of moist peat of 0.3 in the roller bottle bioreactors. A cell count of 1.3 to 1.9 × 10⁹ CFU/g was achieved in 4 d or less, from an initial inoculum of 10⁶ CFU/g. In a rotating drum bioreactor, the growth of R.leguminosarum on peat with sucrose as the main carbon source was completed after 4 d. The majority of growth was in the first 2 d, based on carbon dioxide evolution. These results showed that growth of R. leguminosarum was more rapid in the rotating drum than in bags of peat, due to enhanced oxygen transfer.     

Cell carrier function of hollow-fiber membrane in rotating wall vessel bioreactor

Large-scale expansion of the osteoblasts of a Sprague-Dawley (SD) rat was studied in a rotating wall hollow-fiber membrane bioreactor (RWHMB) by using hollow-fiber membrane as the carrier. For the sake of contrast, cells were also expanded in a T-flask using a hollow-fiber membrane as carrier and in a rotating wall vessel bioreactor (RWVB) using a microcarrier. During the culture period, the cells were sampled every 12 h, and after 5 days, the cells were harvested and evaluated with scanning electron microscopy (SEM), hematoxylin-eosin (HE) staining and alkaline phosphatase (ALP) staining. Moreover, von-Kossa staining and Alizarin Red S staining were carried out for mineralized nodules formation. The results show that in RWHMB, the cells present better morphology and vitality and secrete much more extracellular matrix. It is concluded that the RWHMB combines the advantages of the rotating wall vessel and hollow-fiber membrane bioreactors. The hydrodynamic stimulation within it accelerates the metabolism of the osteoblast and mass transfer, which is propitious to cell differentiation and proliferation.     

Minimal perfusion flow for osteogenic growth of mesenchymal stem cells on lattice scaffolds

A modeling approach to identify sets of culture conditions to promote homogeneous growth of cells in perfusion bioreactors equipped with regular shape scaffolds is proposed. We identify cases in which dynamic culturing is necessary using a zero‐dimensional mass transport and reaction model. Then, based on the three‐dimensional (3‐D) rendering of the flow field inside the bioreactor, we identify regions where cellular growth may become critical; finally, using a 1‐D mass transport and reaction model, we calculate the minimal perfusion flow necessary to maintain the cellular growth rate above a target threshold. The developed approach is used to analyze culturing conditions inside an indirect perfusion bioreactor equipped with a lattice scaffold. Regions where the perfusion flow is inadequate to foster cellular growth at the desired rate are identified. The perfusion flow required to maintain the target growth rate inside the bioreactor is calculated. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3131–3144, 2013     

生物过程工程研究在创新生物医药开发中应用的驱动力——生物反应器

近年创新生物医药在生物产业中的比重逐渐增大,也给生物产业带来了巨大的经济效益,靶点筛选及分子构建等上游技术的进步是促进生物医药进步的主要原因.随着目前细胞培养技术在生物医药生产中的广泛应用,对细胞培养技术的要求也不断提高,同时细胞培养技术的实现载体——生物反应器的技术改进和创新也越发凸显其重要性.本文介绍了生物反应器在创新生物医药产业中的应用种类、发展趋势及发展驱动力,回顾了全球范围内新型生物反应器的发展成果,包括新型反应器技术及过程分析技术在生物医药中的应用,最后,分析了中国生物反应器的发展现状与问题,指出了生物反应器的发展与进步应以提高生物培养过程的稳定性最终提高产品的质量而不是以提高产量为主要目标.本文详细阐述现代生物反应器技术及基于"质量源于设计"的质量控制理念在其中所起到的关键作用,以及生物反应器的技术发展的现状和未来走向.     

Bioprocesses for air pollution control

Bioprocesses have been developed as relatively recent alternatives to conventional, non‐biological technologies, for waste gas treatment and air pollution control in general. This paper reviews major biodegradation processes relevant in this field as well as both accepted and major innovative bioreactor configurations studied or used nowadays for the treatment of polluted air, i.e. biofilters, one‐ and two‐liquid phase biotrickling filters, bioscrubbers, membrane bioreactors, rotating biodiscs and biodrums, one‐ and two‐liquid phase suspended growth bioreactors, as well as hybrid reactor configurations. Some of these bioreactors are being used at full‐scale for solving air pollution problems, while others are still at the research and development stage at laboratory‐ or pilot‐scale. Copyright © 2009 Society of Chemical Industry