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关键词： cell‐   free protein synthesis   CFPS   hydrofoam   oxygen transport   therapeutic protein  

摘要： Protein therapeutics are powerful tools in the fight against diabetes, cancers, growth disorders, and many other debilitating diseases. However, availability is limited due to cost and complications of production from living organisms. To make life-saving protein therapeutics more available to the world, the possibility of magistral or point-of-care protein therapeutic production has gained focus. The recent invention and optimization of lyophilized "cell-free" protein synthesis reagents and its demonstrated ability to produce highly active versions of FDA-approved cancer therapeutics have increased its potential for low-cost, single-batch, magistral medicine. Here we present for the first time the concept of increased oxygen mass transfer in small-batch, cell-free protein synthesis (CFPS) reactions through air-water foams. These "hydrofoam" reactions increased CFPS yields by up to 100%. Contrary to traditional protein synthesis using living organisms, where foam bubbles cause cell-lysis and production losses, hydrofoam CFPS reactions are "cell-free" and better tolerate foaming. Simulation and experimental results suggest that oxygen transfer is limiting in even small volume batch CFPS reactors and that the hydrofoam format improved oxygen transfer. This is further supported by CFPS reactions achieving higher yields when oxygen gas replaces air in the headspace of batch reactions. Improving CFPS yields with hydrofoam reduces the overall cost of biotherapeutic production, increasing availability to the developing world. Beyond protein therapeutic production, hydrofoam CFPS could also be used to enhance other CFPS applications including biosensing, biomanufacturing, and biocatalysis.

关键词： OMS-Sludge   Lipids   Polyphenols   Co-composting   Thermophilic inoculum   Phytotoxicity  

摘要： In Mediterranean countries, the olive oil industry generates the most important agro-industrial wastewater, which results in the production of a highly toxic sludge following effluent decantation, thus endangering the environment. In this investigation, an optimized composting process via microbial inoculation is suggested as to alleviate the toxicity of olive mill solid sludge (OMS-Sludge) through addressing its high polyphenol and lipid content. The composting assay was carried out in a bioreactor using mixtures of sludge and green wastes, with or without microbial inoculation, namely: E1 (49% sludge + 49% green waste + 2% thermophilic Inoculum), and E2 (50% sludge + 50% green waste). After 4 months of composting the inoculation had affected at significantly (p < 0.05)pH, EC and total organic carbon degradation compared to control. Furthermore, HPLC analysis revealed that OMS-Sludge composting significantly diminished the polyphenol content (95% and 85% for E1 and E2, respectively), and the lipid content (90% and 81% for E1 and E2, respectively). More importantly, microbial inoculation resulted in a significant composting efficiency, which was corroborated by a decomposition rate 65% for E1 compared to 62% for E2. In-planta assays showed that both the lipid and polyphenol contents werestrongly correlated with the sludge phytotoxicity with respect to seed germination, which was demonstrated by a substantial improvement of the germination index of Cabbage (64.44%), Turnip (86.58%) and Cress seeds (120.85%). Overall, enhancing the composting process through microbial inoculation resulted in a significant alleviation of the initial mixture phytotoxicity, and proved to be an efficient strategy for OMS-Sludge valorization. [GRAPHICS] .

关键词： Whole-cell catalysis   Bioreactor   Oxygen limitation   Biorefinery   Phanerochaete chrysosporium   Pyranose 2-oxidase   Catalase   Glucosone  

摘要： Biocatalysis using molecular oxygen as the electron acceptor has significant potential for selective oxidations at low cost. However, oxygen is poorly soluble in water, and its slow rate of mass transfer in the aqueous phase is a major obstacle, even for laboratory-scale syntheses. Oxygen transfer can be accelerated by vigorous mechanical methods, but these are often incompatible with biological catalysts. Gentler conditions can be achieved with shallow, high surface area bag reactors that are designed for single use and generally for specialized cell culture applications. As a less-expensive alternative to these high-end bioreactors, we describe repurposing inflatable shipping pillows with resealable valves to provide high surface area mixing under oxygen for preparative synthesis of glucosone (D-arabino-hexos-2-ulose) from D-glucose using non-growing Escherichia coli whole cells containing recombinant pyranose 2-oxidase (POX) as catalyst. Parallel reactions permitted systematic study of the effects of headspace composition (i.e., air vs 100% oxygen), cell density, exogenous catalase, and reaction volume in the oxidation of 10% glucose. Importantly, only a single charge of 100% oxygen is required for stoichiometric conversion on a multi-gram scale in 18 h with resting cells, and the conversion was successfully repeated with recycled cells.

关键词： Acid Blue 29 degradation   Co-metabolism   Electrode biofilm   Integrated microbial fuel cell-aerobic bioreactor   Microbial community   Power generation  

摘要： In this study, an azo dye (Acid Blue 29 or AB29) was efficiently degraded with acetate as co-substrate into less contaminated biodegraded products using an integrated single chamber microbial fuel cell (SMFC)-aerobic bioreactor set-up. The decolorization efficiencies were varied from 91 +/- 2% to 94 +/- 1.9% and more than 85% of chemical oxygen demand (COD) removal was achieved for all dye concentrations after different operating time. The highest coulombic efficiency (CE) and cell potential were 3.18 +/- 0.45% and 287.2 mV, respectively, for SMFC treating 100 mg L-1 of AB29. Electrochemical impedance spectroscopy (EIS) revealed that the anode resistance was 0.3 Omega representing an entirely grown biofilm on the anode surface resulted in higher electron transfer rate. Gas chromatography coupled mass spectrometry (GC-MS) investigation demonstrated that initially biodegradation of AB29 started with the cleavage of the azo bond (-N=N-), resulted the biotransformation into aromatic amines. In successive aerobic treatment stage, these amines were biodegraded into lower molecular weight compounds. The 16S rRNA microbial community analysis indicated that at phylum level, both inoculum and dye acclimated cultures were mainly consisting of Proteobacteria which was 27.9, 53.6 and 68.9% in inoculum, suspension and anodic biofilm, respectively. At genus level, both suspension and biofilm contained decolorization as well as electrochemically active bacteria. The outcomes exhibited that the AB29 decolorization would contest with electrogenic bacteria for electrons. (C) 2020 The Authors. Published by Elsevier B.V.

关键词： Biofouling control   Membrane modification   Visible light photocatalysis   Bacteria inactivation   Anammox MBR  

摘要： The photocatalyst CdS/g-C3N4/rGO, which can simultaneously degrade foulants and inactivate bacteria by illumination, is a promising anti-biofouling modification material for membranes. We tested a novel antibiofouling strategy based on photocatalytic technology in situ in an anammox membrane bioreactor (MBR) assembled with 0.6 wt% CdS/g-C3N4/rGO modified membranes (M2). Compared with the pristine membrane M0, M2 was 9.4% more hydrophilic and had a 13.3% higher water permeability, along with substantially lower flux decline rates for model foulants and significantly higher inhibition rates against model bacteria (p < 0.05). By irradiation of waterproof lights during long-term operation of anammox MBRs, the mean fouling cycle of M2 was extended to 1.92 times that of M0 without compromising the total nitrogen removal efficiency (0.82 (M2) vs. 0.79 (M0), p > 0.05). Moreover, the quantities of organic foulants and total bacteria found on fouled M2 were, respectively, 53.9% and 77.5% lower than those on MO (p < 0.05). We hypothesize that the reactive species (i.e., e(-), h(+), center dot OH) generated on M2 play the predominant role in foulants decomposition and the inactivation of attached bacteria. The novel CdS/g-C3N4/rGO modified membrane holds great promise for the application of visible-light photocatalysis for membrane fouling control in anammox MBRs.

关键词： Anaerobic fluidized bed bioreactor   Forward osmosis   Membrane distillation   Reverse salt flux   Nutrients removal  

摘要： Forward osmosis (FO)-membrane distillation (MD) process was integrated with anaerobic fluidized bed bioreactor (AFBR) to advance wastewater treatment. Low removal efficiency of nutrients such as ammonia nitrogen was improved significantly by combining FO-MD process with AFBR. The MD membrane was applied to concentrate the draw solution (DS) which can be diluted by FO filtration. By using 1 M of NaCl as DS, about 80% of ammonia nitrogen was further removed by the FO membrane while the phosphorous was removed almost completely (99%). However, the accumulation of ammonia nitrogen in DS and the reverse salt flux through the FO membrane was unavoidable. Nevertheless, combining MD membrane produced excellent removal efficiency yielding only 4 and 5.6 mg/L of ammonia nitrogen and chemical oxygen demand (COD) in MD permeate, respectively at 15 degrees C of transmembrane temperature. Alternatively, there is the possibility that the FO-MD process can be superior to concentrate resources such as nitrogen and phosphorous present in AFBR. The reverse salt flux from DS into AFBR bulk suspension did not show adverse effects on the performances of bioreactor with respect to COD removal efficiency, conductivity and methane production during operational period. Deposit of the fouling layer on FO membrane was also observed, but the fouling on MD membrane was not severe probably because crystallization rate could be retarded by diluting the DS during FO filtration.

关键词： Anammox membrane bioreactor   Membrane fouling control   Hydrophilic modification   Extracellular polymeric substances   Gel layer  

摘要： Membrane hydrophilic modification has been applied as an effective antifouling strategy for aerobic and anaerobic heterotrophic membrane bioreactors (MBRs), while its antifouling performance remains unclear for anaerobic ammonium oxidation (anammox) MBR. Herein, hydrophilic membranes (M-h) modified from pristine nylon fabric meshes (M-p, pore size of 20 mu m), were applied in long-term operation of an anammox MBR. Although the average flux of M-h was 90.7% higher than that of M-p < 0.05) filtered with model foulant (bovine serum albumin) in a dead-end filtration test, the average filtration cycle of M-h in the anammox MBR was 37.9% shorter than that of M-p filtered with synthesized wastewater, in spite of the comparable total nitrogen removal efficiency (over 80%) achieved. A thin and compact gel layer was formed on M-h by adsorption of hydrophilic polysaccharide and further gelation of protein and colloidal biomass. The bound water wrapped in the gel layer on M-h brought about 32.8% higher filtration resistance, and caused 81.3% higher contribution rate of the flux decline caused by concentration polarization, compared with M-p. Moreover, more microbial metabolites, especially protein (23.9% vs. 17.7%), was rejected by M-h than M-p, providing organic matters for the proliferation of heterotrophic bacteria, and leading to the decreased relative abundance of anammox bacteria (from 63.2% to 35.2%). We proposed the formation process of the gel layer and revealed the membrane fouling mechanism on M-h in the anammox MBR, providing significant theoretical foundation for the membrane fouling control of anammox MBR systems.

关键词： Wastewater treatment   Sulfate reducing bacteria   Inverse fluidized bed reactor   Metal removal and recovery  

摘要： Acid mine drainage (AMD) is a serious environmental hazard in many countries with historic or ongoing mining industries. Biological sulfide precipitation is an emerging technique for both removal and recovery of heavy metals from such wastewater. This study demonstrated heavy metal removal and recovery from synthetic wastewater containing Cd2+, Cu2+, Fe3+, Ni2+, Pb2+ and Zn2+ using two continuously operated sulfidogenic anaerobic inverse fluidized bed reactors (referred as R1 and R2) supplied with an influent of pH 7.0 and 3.0, respectively. In case of R1, more than 95% metal removal efficiency was achieved for all the metals except for Fe3+ (90%) and Ni2+ (85%), and in case of R2 the removal was more than 90% for all the metals except with Fe3+ (88%) and Ni2+ (82%). The metals were subsequently recovered in the form of metal nanopowder from the reactor bottom and equalizer, and the metal recovery was in the order: Cu > Pb > Cd > Zn > Ni > Fe. However R1 yielded a good recovery percentage (50-65%) of the metals in comparison with the reactor supplied with influent of pH 3.0 (46 -55%). The presence of immobilized sulfate reducing bacteria onto the support material in the bioreactors were identified using field emission scanning electron microscopy. The size and shape of the biometal nanoparticles were confirmed using field emission transmission electron microscopy, which revealed their excellent potential for industrial application. This study demonstrates successful recovery of metal sulfides in the form of nanoparticles using IFBR. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Anammox   Hydraulic retention time   Nitrogen removal efficiency   pH   Preliminary assessment   Reactor performance  

摘要： In order to assess the performance of anaerobic ammonium oxidation (anammox) bioreactors, it is necessary to study the stoichiometry of the anammox reaction and pH. This study focused on the effect of the hydraulic retention time (HRT) on the effluent pH in anammox-upflow anaerobic sludge blanket (UASB) bioreactors. Anammox-UASB bioreactors with and without a recirculation system were used to investigate the effluent pH and bioreactor performance. It was concluded that under varying HRT conditions, the decrease in effluent pH did not indicate the deterioration of nitrogen removal, but did indicate that the nitrogen removal efficiency was reduced owing to a sudden increase in the nitrogen loading rate resulting from the decrease in HRT. Moreover, the results showed that the HRT directly affected the concentration of OH-, which affected the increase/decrease in effluent pH. This study demonstrated that effluent pH is a more powerful tool than previous techniques used to assess bioreactor performance. We suggest that the effluent pH could be used for preliminary assessment.

关键词： Polychlorinated biphenyls   Paraburkholderia xenovorans LB400   Lab bioreactor experiments   Bioremediation   Biodegradation   Bioavailability   Bioaccesibility   Biotransformation  

摘要： Experiments were conducted to measure biodegradation of polychlorinated biphenyl (PCB) congeners contained in mixture Aroclor 1248 and congeners present in wastewater lagoon sediment contaminated decades earlier at Altavista, Virginia. A well-characterized strain of aerobic PCB-degrading bacteria, Paraburkholderia xenovorans LB400 was incubated in laboratory bioreactors with PCB-contaminated sediment collected at the site. The experiments evaluated strain LB400's ability to degrade PCBs in absence of sediment and in PCB-contaminated sediment slurry. In absence of sediment, LB400 transformed 76% of Aroclor 1248 within seven days, spanning all homolog groups present in the mixture. In sediment slurry, only mono- and di-chlorinated PCB congeners were transformed. These results show that LB400 is capable of rapidly biodegrading most PCB congeners when they are freely dissolved in liquid but cannot degrade PCB congeners having three or more chlorine substituents in sediment slurry. Finally, using GC/MS-MS triple quadrupole spectrometry, this work distinguishes between physical (sorption to cells) and biological removal mechanisms, illuminates the process by which microorganisms with LB400-type congener specificity can selectively transform lower-chlorinated congeners over time, and makes direct comparisons to other studies where individual congener data is reported. (C) 2020 Published by Elsevier Ltd.