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关键词： low pressure reverse osmosis membrane   upflow anaerobic sludge blanket reactor   brewery wastewater   water reuse   ultrafiltration   granular activated carbon adsorption  

摘要： The low-pressure reverse osmosis (LPRO) process is a recent development of reverse osmosis (RO) technology for the reduction in RO energy consumption and operation cost. The goal of this study was to investigate the performance of LPRO processes for the treatment and reuse of effluent discharged from brewery upflow anaerobic sludge blanket bioreactors (UASB). In this study, three different commercially available LPRO membranes were tested to evaluate the water quality that can be achieved under different operational and pretreatment conditions. It was found that the filtration performance and the effluent quality of the LPRO membranes can be considerably affected by the operation conditions and the selection of the pretreatment processes. The ultrafiltration (UF) pretreatment and the control of the operation pressure were found to be essential for mitigating LPRO membrane fouling, which could be caused by Ca2+ associated precipitates and organic gelation, in the treatment of the brewery UASB effluent. Water quality analyses showed that an integrated process of the UASB + UF + LPRO could achieve an effluent quality characterized by concentrations of 10.4-12.5 mg/L of chemical oxygen demand (COD), 1.8-2.1 mg/L of total nitrogen (TN), 1.3-1.8 mg/L of ammonia nitrogen (NH3-N) and 0.8-1.2 mg/L of total phosphorus (TP). The effluent quality and the LPRO performance could be further improved by adding a granular activated carbon (GAC) adsorption process between the UF and LPRO processes, which reduced the concentration of COD to 7-10 mg/L and those of TN, TP, NH3-N to below 1 mg/L. For the treatment of the UASB effluent tested in this study, the UF, UF + GAC (retention time 4 hrs), UF + LPRO, and UF + GAC + LPRO, respectively, achieved overall COD removal efficiencies of 89.6-93.7%, 94.5-96.7%, 99.3-99.1% and 99.3-99.4%;TN removal efficiencies of 73.0-78.2%, 89.2-97.2%, 97.1-98.2% and 94.3-99.7%;and TP removal efficiencies of 29.3-46.2%, 77.0-95.4%, 95.9-97.6z% and 98.0-98

摘要： Beta (beta)-mannanase is one of the most important enzymes used in the industry and they are produced in particularly withAspergillus sojae. In this study, large-scaled mannanase production by recombinantA. sojae(ATCC 11906) was performed at 30oC, 15 lpm aeration rate, and 204 rpm stirring speed in the bioreactor (30-L). Fed-batch and microparticle enhanced cultivation strategies were used to improve the scale-up production in both glucose and carob pod extract media. For this purpose, different concentrations of magnesium silicate (3MgO.4SiO(2).H2O, talc) (1, 3, 5, and 10 g/L) and aluminum oxide (Al2O3) (1, 5, 10, and 15 g/L) as microparticle agents were supplemented into the fermentation media. The maximum enzyme activity was determined from carob extract-based medium as 302.6 U/ml with the addition of 3 g/L of magnesium silicate. Microparticle-enhanced large-scale bioreactor was successfully used to control the fungal growth, to perform repeatable fermentations, and to scale-up beta-mannanase productions in fermentation. Practical applications The role of mannanases in the energy, detergent, paper, pulp, and feed industry is well established and recently they have found the application field in the food technologies such as fruit maceration, gum modification, production of instant coffee and prebiotics, etc. Mannanases are mostly extracellular enzymes hydrolyzing the 1,4-beta-D-mannosidic linkages in mannans, galactomannans, glucomannans, and galactoglucomannans. Mannanases are enzymes produced mainly from microorganisms but mannanases produced from plants have also been reported. However, microbes are the most potent producers of mannanases and represent the preferred source of enzymes because of their rapid growth, limited spaces required for cultivation, and ready accessibility to genetic manipulation. Microbial mannanases have become biotechnological importance since they target the hydrolysis of complex polysaccharides of plant tissues into simple molecules

关键词： Netrin-1   Bioreactor   Sleeping beauty   Extracellular matrix protein production   Biophysical quality control  

摘要： The production of recombinant proteins for functional and biophysical studies, especially in the field of structural determination, still represents a challenge as high quality and quantities are needed to adequately perform experiments. This is in part solved by optimizing protein constructs and expression conditions to maximize the yields in regular flask expression systems. Still, work flow and effort can be substantial with no guarantee to obtain improvements. This study presents a combination of workflows that can be used to dramatically increase protein production and improve processing results, specifically for the extracellular matrix protein Netrin-1. This proteoglycan is an axon guidance cue which interacts with various receptors to initiate downstream signaling cascades affecting cell differentiation, proliferation, metabolism, and survival. We were able to produce large glycoprotein quantities in mammalian cells, which were engineered for protein overexpression and secretion into the media using the controlled environment provided by a hollow fiber bioreactor. Close monitoring of the internal bioreactor conditions allowed for stable production over an extended period of time. In addition to this, Netrin-1 concentrations were monitored in expression media through biolayer interferometry which allowed us to increase Netrin-1 media concentrations tenfold over our current flask systems while preserving excellent protein quality and in solution behavior. Our particular combination of genetic engineering, cell culture system, protein purification, and biophysical characterization permitted us to establish an efficient and continuous production of high-quality protein suitable for structural biology studies that can be translated to various biological systems.

摘要： The aim of this study was to determine the toleration limit of furfural concentration (0.1-10 g/L) in the medium for ethanol fermentation using immobilized cells ofSaccharomyces cerevisiaein the bioreactor with glucose-based media and to model the fermentation. Results showed that the highest ethanol yield and production were 47.62% and 36.40 g/L when 0.5 and 2 g/L of furfural were added in the medium, respectively. In contrast, the lowest yield and production were 5.40% and 0.57 in 10 g/L of furfural. Thus, the furfural has been found to adversely affect the ethanol yield even the yeast was immobilized. Nevertheless, the yeast can grow up to a furfural concentration of 6 g/L. Regarding modeling, the experimental ethanol production, sugar consumption, and biomass production data of the fermentation performed by adding 2 g/L of furfural were successfully predicted by MGM, MMF, and Weibull model. Practical applications In the pretreatment of renewable resources that can be used to produce ethanol, inhibitors are formed, which inhibit the microbial growth and the product formation. Detoxification methods are commonly used to remove the inhibitors. In this study, the immobilization technique was used to protect the yeast growth and thus product formation from inhibition. Yeast cells were covered with Ca-alginate by immobilization. Cells protected with alginate exposed less to inhibition. Protected cells remained more active in this way. Based on the results, this technique was successful since the ethanol was produced in the glucose-based medium including furfural. The results also showed that no detoxification was required and that the process saves time and energy.

关键词： Groundwater treatment   Granular sludge   Biological denitrification   Microbial ecology   Nitrate-polluted water  

摘要： A sequential bed granular bioreactor was adapted to treat nitrate-polluted synthetic groundwater under anaerobic conditions and agitation with denitrification gas, achieving very efficient performance in total nitrogen removal at influent organic carbon concentrations of 1 g L-1 (80-90%) and 0.5 g L-1 (70-80%) sodium acetate, but concentrations below 0.5 g L-1 caused accumulation of nitrite and nitrate and led to system failure (30-40% removal). Biomass size and settling velocity were higher above 0.5 g L-1 sodium acetate. Trichosporonaceae dominated the fungal populations at all times, while a dominance of terrestrial group Thaumarchaeota and Acidovorax at 1 and 0.5 g L-1 passed to a domination of Methanobrevibacter and an unclassified Comamonadaceae clone for NaAc lower than 0.5 g L-1. The results obtained pointed out that the denitrifying granular sludge technology is a feasible solution for the treatment of nitrogen-contaminated groundwater, and that influent organic matter plays an important role on the conformation of microbial communities within it and, therefore, on the overall efficiency of the system.

关键词： bioprocessing   bioreactors   cultivated beef   microcarriers   scale-up  

摘要： Cultivated meat is an emerging field, aiming to establish the production of animal tissue for human consumption in an in vitro environment, eliminating the need to raise and slaughter animals for their meat. To realise this, the expansion of primary cells in a bioreactor is needed to achieve the high cell numbers required. The aim of this study was to develop a scalable, microcarrier based, intensified bioprocess for the expansion of bovine adipose-derived stem cells as precursors of fat and muscle tissue. The intensified bioprocess development was carried out initially in spinner flasks of different sizes and then translated to fully controlled litre scale benchtop bioreactors. Bioprocess intensification was achieved by utilising the previously demonstrated bead-to-bead transfer phenomenon and through the combined addition of microcarrier and medium to double the existing surface area and working volume in the bioreactor. Choosing the optimal time point for the additions was critical in enhancing the cell expansion. A significant fold increase of 114.19 +/- 1.07 was obtained at the litre scale in the intensified bioprocess compared to the baseline (**p < .005). The quality of the cells was evaluated pre- and post-expansion and the cells were found to maintain their phenotype and differentiation capacity.

关键词： Organic removal   attached-growth biofilm   microbial community diversity   nitrification-denitrification   domestic wastewater treatment  

摘要： An MBBR and CW combo bio-reactor (MBCW) was designed as a novel hybrid process for simultaneous organic, nitrogen and phosphate removal through the long-term operation. The effect of the internal recycling rate (IRR), hydraulic retention time (HRT) and chemical oxygen demand/total nitrogen (C/N) ratio were all discussed, and the recommended values were 5:1, 12 h and >6, respectively. A higher C/N ratio was a key factor for achieving a higher TN removal. The mixed biocarrier system was realized by inoculating porous polymer carriers (PPC) and cylindrical polyethylene carriers (CPC) and achieving a higher organic biodegradation and nitrification rate compared to a single carrier system. Microorganism activities and plants' uptake or utilization both contributed to the nutrient removal in a constructed wetland. High-throughput sequencing results revealed an abundant microbial diversity and a distinct microbial distribution in the whole system where Flavobacterium (14.2%), Acinetobacter (12.87%) and Rhodobacter (10.83%) dominated on PPC, Terrimonas (8.88%), Reyranella (6.61%) and Rubinisphaera (5.63%) dominated on CPC, Comamonas (4.18%), Gemmobacter (4.02%) and Hydrogenophaga (3.97%) dominated on CWs, as well as Citrobacter (53.13%) on suspended floc.

关键词： Micropollutants   YES assay   Microbial community   Sewage treatment   Risk assessment  

摘要： Pharmaceutically active compounds (PhACs) may cause harmful effects in living beings, and advanced treatment is required to improve wastewater treatment plant efficiency. In this context, this study aimed to assess the performance of a hybrid anaerobic osmotic membrane bioreactor coupled with a membrane distillation system (AnOMBR-MD) for removing PhACs and estrogenic activity from municipal sewage. Human health and environmental risks of produced water were also assessed. The removal efficiency of dissolved organic carbon and PPO43- reached 97.2% and 98.0%, respectively. N-NH4+ accumulated in the bioreactor since anaerobic treatment can not remove it. Salinity increase in the bioreactor caused a great change in the microbial community, with Chao 1 and Shannon indexes higher in the sludge after 50 days of operation than in the sludge used as inoculum. Estrogenic activity of municipal sewage spiked with PhACs was >3 times higher than the expected value calculated by the additive model (2 ?g L-1E2-eq.), which indicates that some of the PhACs effects increased in the presence of others. Estrogenicity was not detected in distillate samples, which greatly reduced human health risks to acceptable values. Of the 7 PhACs selected in this study, only betamethasone, fluconazole, and prednisone were detected in the distillate. However, the overall removal of PhACs by the AnOMBR-MD system was higher than 96.4%. The chronic environmental risk considering the estrogenic activity was classified as high because of the detection limit in the yeast estrogen screen (YES), which supports the need for improving bioassay sensibility. The results demonstrated that the use of the YES assay combined with detection and identification of micropollutants allowed an effective assessment of the overall treatment performance.

关键词： Agglomeration   Extracellular polymeric substances (EPS)   Mine-impacted waters   Nickel   Cobalt   Sulfate reducing bacteria (SRB)  

摘要： In this study, a single-stage up-flow fixed-bed sulfidogenic bioreactor was operated for 288 days (six stages), treating mine-impacted water at different concentrations of nickel (Ni), cobalt (Co) and other associated metals. The effect of metals on the sulfate reducing activity, metal recovery, extracellular proteins and microbial diversity was evaluated. The bioreactor configuration showed a positive synergistic effect on both sulfate reducing activity and metals recovery, which could treat up to 200 mg/L Ni. Over 99% of Ni and Co, as well as over 91% of the other metals in the influent, precipitated and settled in the bioreactor regardless of the initial metal concentration. The scanning electron microscopy (SEM) analysis of the precipitates showed the presence of extracellular polymeric substances (EPS), which may have helped to agglomerate the metal sulfide precipitates increasing their ?particle size? from 0.1 to 0.5 ?m to 10?100 ?m. Different extracellular proteins associated to these EPS increased in abundance upon variations of the bioreactor operation. These included proteins involved in enzymatic reactions and metal binding, such as periplasmic [NiFeSe] hydrogenase, standing out when Ni and Co was added. The biofilm characterization showed the dominance of metal-tolerant SRB genera (e.g., Desulfomicrobium spp. and Desulfovibrio spp.), but also of other non-SRB, demonstrating that a higher microbial diversity may help the biofilm endure higher metal concentrations.

关键词： Salt acclimatization   Osmotic stress   Biological nitrogen removal   Marine recirculating aquaculture systems   (RAS)   Biofilter inoculation  

摘要： Recirculating aquaculture systems (RAS) for anadromous fish such as salmonids often require salinity changes during the production cycle. However, high or variable salinity can disrupt the biological nitrification process, which can be detrimental to the fish due to the accumulation of toxic ammonia or nitrite. Thus, it is vital to maintain sufficient nitrification capacity in RAS during salinity changes. This study investigated whether seeding with salinity-acclimated carriers in the freshwater start-up phase could increase the salinity tolerance of nitrifying bioreactors. Moving bed biofilm reactors (MBBR) were started with virgin carriers and seeded with mature biofilm carriers acclimated to freshwater (F), brackish water (B, 12%o salinity), or a 1:1 mix of both (FB). All duplicate reactors were started up in freshwater and the salinity was increased to seawater (-32%o salinity) after -7 weeks. While F and FB had a 65-75% decrease in ammonia oxidation capacity immediately after seawater transfer, B had only a -20% reduction. After 40 days in seawater, ammonia oxidation recovered completely and became similar in all treatments. However, nitrite accumulation was observed in all the treatments several days after the salinity increase, with the least accumulation in B and the highest in F. The type of seeding influenced the composition of the nitrifying microbial community in the new biofilms (in the freshwater phase). However, the composition in the treatments became similar after -6 weeks in seawater. The findings indicate that seeding with brackish water biofilm carriers is a potential strategy for accelerating start-up and improving the acclimation of freshwater nitrifying bioreactors to salinity stress. However, nitrite oxidizing bacteria may require a longer period for salinity adaptation. Thus, it is important to closely monitor the nitrite concentration for a prolonged period (several days or weeks) after a salinity increase.