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关键词： Natural colorants   Talaromyces amestolkiae   Cell morphology   Bioreactor   Scaling-up  

摘要： Fungi bioproducts have recently become commercially important to the food and pharmaceutical industry. However, different structural forms exhibited by filamentous fungi throughout their life cycles are often a bottleneck for productivity in many industrial processes. In this work, the relationship among mycelium accumulation, morphology, and colorant production was evaluated. Experiments were performed in an incubator shaker and in a stirred-tank bioreactor. First, a series of nitrogen sources and pure vitamins were investigated as additives to the monosodium glutamate-glucose medium in order to improve Talaromyces amestolkiae red colorant production in the incubator shaker. MSG and pH played an important role in generating stress, which affected cell growth and colorants production. The colorant synthesis seems to be is triggered under metabolic stress. Next, the effects of starter culture composition (MSG-glucose and nitrogen complex starter media) and airflow (2.0 and 8.0 Lmin())(-1) were investigated in the bioreactor. After 120 h of cultivation in the bioreactor, a maximum red colorant production of 9.33 UA(500nm), 72.38 % glucose consumption, and 4.53 g L-1 biomass concentration were achieved under complex nitrogen as starter medium at 8 Lmin(-1). Growth remained at moderate level, probably affected by the synergistic effect of MSG and pH as stress factors. Moreover, pellets formation favored suitable oxygenation of the culture broth leading to the best consumption of the carbon source.

关键词： 3D printing   molecular diagnostics   saliva sample   LAMP   DNA micro-reactor  

摘要： The aim of this work is to employ 3D printing for the fabrication of bioreactors for DNA amplification with the long term aim to use them to healthcare applications. Initially, the most suitable printing material for the amplification reactor was evaluated by testing 25 different commercially available filaments, 3D-printed through the fused filament fabrication (FFF) method. Evaluation was carried out against materials printing efficiency, compatibility with the enzymatic DNA amplification assay and transparency. The best-performing transparent material was further used for the fabrication of a cartridge with eight micro-well reactors; the latter was demonstrated to be able to perform LAMP isothermal amplification in saliva samples when placed inside a purpose-made 3D printed portable platform. The successful detection of the CYP2C19*2 mutation involved in the metabolism of clopidogrel (Plavix), a drug used as a treatment to cardiovascular diseases, demonstrates the suitability of the platform as a companion diagnostic tool, emphasizing the potential of the method as a point-of-care system.

关键词： Adsorption   flux   granular activated carbon   heavy metal removal   membrane bioreactor  

摘要： The removal of nickel, lead, arsenic, and zinc was investigated by a lab-scale submerged membrane bioreactor (MBR) combined with granular activated carbon (GAC). Membrane fluxes of 16 L m(-2)h(-1), 20 L m(-2)h(-1), and 24 L m(-2)h(-1)with corresponding hydraulic retention times (HRTs) of 12.8 h, 10.4 h, and 9.2 h were applied as variables to examine their influence upon the removal efficiency. Synthetically prepared wastewater was pretreated in the MBR and GAC adsorption was employed as the post-treatment. Under the lowest applied flux value or, equivalently, the highest HRT applied, chemical oxygen demand (COD), ammonium (NH4-N) and phosphate (PO4-P) removals were found to be the highest (96.8%, 98.9% and 46%, respectively) for the MBR effluent. These results may be considered to be the result of alleviated membrane fouling and greater biomass growth. The highest heavy metal removal efficiency after the first treatment stage (i.e. the MBR effluent) was obtained at the lowest flux value of 16 L m(-2)h(-1). Ni, Pb, Zn, and As removals were measured to be equal to 96.9%, 98.3%, 98% and 8.5%, respectively. More important, the heavy metal concentrations were below the limit of detection after the GAC post-treatment;over 99% removal was achieved for all heavy metals. The adsorption of heavy metal ions onto the GAC may minimize biomass exposure to their toxicity, thereby creating the conditions for further improved MBR-GAC system performance. Coupling MBR technology with GAC adsorption seems a promising option for the effective treatment of wastewater containing heavy metals.

关键词： Ammonium   hydraulic retention time   membrane bioreactor   membrane flux   organic content   phosphates  

摘要： The effect of applying different hydraulic retention times (HRTs) was investigated for a lab-scale membrane bioreactor (MBR) treating domestic wastewater. The submerged flat-type ultrafiltration MBR was operated under three HRTs (576 min, 462 min, and 372 min) corresponding to three operating periods to investigate its efficiency in removing organic content and nutrients from domestic wastewater. The chemical oxygen demand (COD) decreased from 99 to 96.5% with the HRT decreased from 576 min to 462 min. The bacteria performing nitrification were affected by the HRT change: the ammonium (NH4-N) removal dropped from 98.5% (HRT of 576 min) to 74.2% (HRT of 462 min). With the HRT adjusted to the lowest value of 372 min, the COD and NH4-N removals were 94.4% and 55.8%, respectively. The phosphate (PO4-P) removal was 59.1%, 34.4%, and 28% during periods 1, 2 and 3, respectively. In terms of the COD removal efficiency, the treated effluent met the Turkish limits for discharge to the receiving water during all of the operating periods. The system performance was suitable in terms of NH4-N removal for periods 1 (HRT of 576 min) and 2 (HRT of 462 min). However, applying the operating conditions of period 2 (i.e., maintaining the HRT at 462 min) requires additional post-treatment (e.g., low-cost chemical precipitation) to enhance the PO4-P removal.

关键词： Anaerobic membrane bioreactor (AnMBR)   Life cycle assessment   Domestic wastewater treatment   Nutrient and sulfide removal   Dissolved methane   Life cycle cost analysis  

摘要： The use of the anaerobic membrane bioreactor (AnMBR) process for domestic wastewater treatment presents an opportunity to mitigate environmental, social, and economic impacts currently incurred from energy-intensive conventional aerobic activated sludge processes. Previous studies have performed detailed evaluations on improving AnMBR process subcomponents to maximize energy recovery and dissolved methane recovery. Few studies have broadly evaluated the role of chemical use, membrane fouling management, and dissolved methane removal technologies. A life cycle assessment was conducted to holistically compare multiple AnMBR-based domestic wastewater treatment trains to conventional activated sludge (CAS) treatment. These treatment trains included different scouring methods to mitigate membrane fouling (gas-sparging and granular activated carbon-fluidizing) with consideration of upstream treatment (primary sedimentation vs. screening only), downstream treatment (dissolved methane removal and nutrient removal) and sludge management (anaerobic digestion and lime stabilization). This study determined two process subcomponents (sulfide and phosphorus removal and sludge management) that drove chemical use and residuals generation, and in turn the environmental and cost impacts. Furthermore, integrating primary sedimentation and a vacuum degassing tank for dissolved methane removal maximized net energy recovery. Sustainability impacts were further mitigated by operating at a higher flux and temperature, as well as by substituting biological sulfide removal for chemical coagulation.

关键词： Cornstalk hydrolysates   expanded bed adsorption bioreactor   fed-batch fermentation   propionic acid   vitamin B12  

摘要： Vitamin B12 and propionic acid that were simultaneous produced by Propionibacterium freudenreichii are both favorable chemicals widely used in food preservatives, medicine, and nutrition. While the carbon source and propionic acid accumulation reflected fermentation efficiency. In this study, using corn stalk as a carbon source and fed-batch fermentation process in an expanded bed adsorption bioreactor was studied for efficient and economic biosynthesis of acid vitamin B12 and propionic. With liquid hot water pretreated corn stalk hydrolysates as carbon source, 28.65 mg L-1 of vitamin B12 and 17.05 g L-1 of propionic acid were attained at 168 h in batch fermentation. In order to optimize the fermentation outcomes, fed-batch fermentation was performed with hydrolyzed corn stalk in expanded bed adsorption bioreactor (EBAB), giving 47.6 mg L-1 vitamin B12 and 91.4 g L-1 of propionic acid at 258 h, which correspond to product yields of 0.37 mg g(-1) and 0.75 g g(-1), respectively. The present study provided a promising strategy for economically sustainable production of vitamin B12 and propionic acid by P. freudenreichii fermentation using biomass cornstalk as carbon source and expanded bed adsorption bioreactor.

关键词： 生物反应器与分离工程   混合式教学   教学改革  

摘要： 生物反应器与分离工程是海军军医大学生物技术专业的专业必修课,是一门理论性、应用性和实践性较强的课程。为进一步突出海军军医大学的海洋、军事特色,课程组成员全方位构筑高质量的生物反应器与分离工程课程教学体系。通过一系列混合式教学模式改革,充分利用互联网资源,优化教学内容,突出学习过程设计、学习能力培养,使学员成为学习的主体,建立新的成绩与教学效果评价体系。通过该课程的学习,显著提高了学员的学习积极性、主动性与学习能力,教学效果得到了提升。

关键词： 工业废水   膜生物反应器   膜污染控制  

摘要： 膜生物反应器,因性能优势应用于多种工业废水处理或回收利用。膜污染问题是影响其处理效率和推广应用的主要因素。为解决工业废水处理中的膜污染问题,通过分析膜污染形成机理,研究膜污染产生因素,针对性地提出了膜污染控制技术措施。最后,对膜生物反应器的热点研究和应用方向进行了讨论。

关键词： 膜生物反应器   污水处理   膜污染  

摘要： 膜生物反应器是一种高效能、新技术的废水处理反应装置,可以把生物反应器以及膜分离技术相结合,具有更高效能的处理废水的能力。文章将重点研究使用特点以及如何使用在处理污水当中,并介绍了膜生物反应器目前仍然存在着的一些问题。

关键词： 生物反应器   接种疫苗   纳瓦拉   两层楼   首席执行官   阿达尔   玻璃瓶  

摘要： 首席执行官阿达尔·波纳瓦拉(Adar Poonawalla)执掌的印度血清研究所(Serum Institute of India)是全球最大的疫苗供应商,每年能生产约15亿剂人体接种疫苗,几乎涵盖各个门类。该公司拥有的设备每分钟能灌装500支小玻璃瓶,数座闪闪发光、接近两层楼高的钢质生物反应器每个月能生成超过1000万剂疫苗的药液。他可以令人信服地宣称,他为分布在100多个国家和地区的全世界65%的儿童预防麻疹和肺结核等疾病做出了贡献。