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关键词： Biocontrol   Sugarcane crops   Solid-state fermentation   Scale-up  

摘要： This paper presents a study on scale-up and cost reduction of the production of spores of Metarhizium anisopliae IBCB 425, entomopathogenic fungus used in sugarcane crops. Rice was mixed with sugarcane bagasse (9:1 w/w) for substrate composition, assuring adequate physical structure for cultivation in packed-beds. Spores yield from only rice in bench-scale packed-bed bioreactor was 56 % of the one obtained from the mixture 9:1 w/w. In comparison to plastic packages used in bioindustries, equivalent spores yields per gram of substrate have been achieved in bench and pilot-scale bioreactors built by cylindrical jacketed modules, that provide better control of operational and environmental variables, attested by little variability among replicates. Although non-negligible temperature rise (5 degrees C above the ideal) occurred within the pilot-scale bioreactor, spores production was not harmed in comparison to bench-scale. By reusing rice up to three successive cultivations, a 2.5-fold increase of spores yields was achieved in comparison to single use. Temperatures and CO2 profiles corroborates the fungus adapted differently to substrate at each usage. Such results are valuable for industrial producers of commercial formulations of the fungus spores, allowing process modernization by using packed-bed bioreactors and production costs and rice demand reduction by recycling the substrate.

关键词： Kinetics   Pharmaceutical   Metabolite   Wastewater   Transformation  

摘要： The fate of selected common pharmaceuticals and four of their major conjugates in wastewater batch bioreactors was evaluated to determine how treatment plant parameters such as addition of air, and the presence of waste activated sludge (WAS) could influence the removal of parent compounds and conjugates. Under a realistic hydraulic residence time (HRT) for each treatment sub-process of approximately 2 h, acetaminophen and its sulfate metabolite were both rapidly degraded (>99%). Propranolol was sulfated and concurrently removed. Deconjugation of N-acetylsulfamethoxazole and sulfamethoxazole-glucuronide contributed to increases of the parent sulfamethoxazole. Thyroxine was resistant to degradation, while thyroxine-glucuronide was rapidly deconjugated (>90% in <2 h). In the absence of WAS, sorption to suspended solids was another major removal mechanism for acetaminophen, propranolol, sulfamethoxazole, and thyroxine. However, with WAS, concentrations associated with suspended solids decreased for all analytes within 24 h. These results indicate that both conjugation and back-transformation are compound-specific and dependent on parameters such as HRT, addition of microbial content, and suspended solids levels. Therefore, conjugation-deconjugation processes may strongly influence the speciation of pharmaceuticals and their fate in wastewater treatment plant effluents. (C) 2020 Elsevier Ltd. All rights reserved.

关键词： Denitrification   Phosphorus removal   Bacterial immobilized reactor   Tetracycline adsorption   High-throughput sequencing  

摘要： Single denitrification using bacteria has been widely investigated, but few studies have focused on the simultaneous removal of nitrate, phosphorus. and tetracycline. Strain L2, an iron-reducing bacteria, was immobilized using chitosan/polyvinyl alcohol to simultaneously remove nitrate and phosphorus. The effects of carbon/nitrogen ratio (1:1, 1.5:1, and 2:1), initial Fe2+ concentration (0, 15, and 30 mg center dot L-1), and HRT (2, 4, and 6 h) were assessed in bioreactors and optimum conditions were established. Results showed that the nitrate and phosphorus removal efficiency reached 100.00% (2.697 mg center dot L-1 center dot h(-1)) and 81.93% (1.533 mg center dot L-1 center dot h(-1)) under the conditions of carbon/nitrogen of 2:1, Fe2+ concentration of 30 mg center dot L-1 and HRT of 6 h. The precipitation of bioreactor, which identified as FeOOH by XRD, had significant adsorption on tetracycline. The results of high-throughput sequencing indicated that strain L2 played a significant role in denitrification. This bioreactor provided effective method for the treatment of polluted water contaminated by nitrate, phosphorus, and tetracycline. [GRAPHICS] .

关键词： RuBisCo   E. coli   Bioreactor   CO2 assimilation   Chaperone  

摘要： Global warming is a surging issue that has provoked the demand of green process to mitigate carbon dioxide. In this context, RuBisCo-equipped Escherichia coli has first developed and evaluated the CO2-assimiliable capability based on the mass balance in three devices: Flask-based in CO2 incubator (FIC), two-layered device (TLD) and CO2 bubbling device (CBD) systematically. With the forced diffusion of 5% CO2 in CBD, which confers an efficient attack of CO2 to RuBisCo, the CO2 assimilation increased from -5.03 to -2.63 g-CO2/g-DCW. Furthermore, boosted CO2 ( )assimilation ability was observed by co-expression of GroELS chaperone with 71% reduction on CO2 release. By DNA sequencing and tandem MS/MS analysis, the toxicity of RuBisCo and PRK was identified to interfere the sugar metabolism and energy producing, while the cell morphology was changed and observed in RuBisCo-equipped E. coli. Our study provides a new perspective of higher CO2 assimilation for sustainable to eco-friendly green bioprocess.

关键词： Carbamazepine   Forward osmotic membrane bioreactor   Contaminant removal   Microbial community  

摘要： A submerged forward osmotic membrane bioreactor (FOMBR) was used to reveal the removal and degradation mechanism of carbamazepine (CBZ) from wastewater. The results showed that the removal mechanism consisted of the rejection of the forward osmotic (FO) membrane and biodegradation of the activated sludge. The removal efficiencies of COD, NH4+-N, and CBZ by the FOMBR were approximately 94.77%-97.45%, 93.56%-99.28%, and 88.20%-94.45%, respectively. Moreover, the COD and NH4+-N removal efficiencies were positively correlated with the increased CBZ concentrations. The results of the soluble microbial products (SMP) and extracellular polymeric substances (EPS) tests illustrated that the membrane fouling potential of EPS may be higher than that of SMP. According to the identified 14 degradation products, oxidation, hydroxylation, and decarboxylation were defined as the primary CBZ degradation mechanism. In addition, the RNA results showed that Delftia could be the characteristic bacteria in the CBZ degradation process.

关键词： Membrane electro-bioreactor (MEBR)   Seawater treatment   Membrane fouling   Microbial community   Recirculating aquaculture system (RAS)  

摘要： Ammonia and nitrite in aquaculture recirculating seawater need to be strictly controlled to avoid deleterious effects on aquatic organisms. However, traditional biological approach can hardly meet the standard due to the short hydraulic retention time (HRT) and nitrite accumulation. A Membrane Electro-Bioreactor (MEBR) was developed for ammonia removal enhancement and in-situ electrochemical membrane fouling mitigation. The fouling mechanism was first found to proceed via the standard filtration model. The flux decrease was mainly caused by an internal pore clogging phenomenon. Membrane fouling resistance was enhanced by increasing anode potential from 0 to 1.4 V vs. SCE (Saturated Calomel Electrode). The ammonia removal rate in the MEBR was above 95% (HRT: 2 h, after day-13) and membrane fouling was mitigated that operation duration was extended by 71.4%. Higher total proportion of Proteobacteria, Bacteroidetes, Planctomycetes and Actinobacteria was obtained in the MEBR, suggesting higher nitrification and nitrogen removal potentials.

关键词： Flowback water   Aerobic granular sludge   Bacterial community   Artificial neural network  

摘要： Flowback water from shale gas extraction is highly saline and comprises complex organic substances, thereby posing a significant challenge for the environmental management of the unconventional natural gas industry. In this work, an aerobic granular sludge (AGS) method was successfully used for the treatment of flowback water from shale gas extraction. The formed AGS had a diameter of 0.25-2.0 mm and the total sludge volume index was 23.40 mL g(-1). The AGS efficiently removed COD, NH4+-N and TN by 70.1%, 92.1%, and 59.2%, respectively. The bacterial communities responsible for the removal of nitrogen and degradation of organics were enriched in AGS. The dynamics of contaminant removal was further explained with a three-layered artificial neural network model. The results showed that the initial concentration of COD, TDS, NH4+-N and TN governed the contaminants' removal. As for operating parameters, aerating time showed a strong effect on NH4+-N and TN removal, whereas settling time impacted the COD removal.

关键词： Osteomyelitis   Local antibiotic release   In vivo bioreactors   Large animal model   Tissue engineering   Mandibular repair  

摘要： Mandibular reconstruction requires functional and aesthetic repair and is further complicated by contamination from oral and skin flora. Antibiotic-releasing porous space maintainers have been developed for the local release of vancomycin and to promote soft tissue attachment. In this study, mandibular defects in six sheep were inoculated with 106 colony forming units of Staphylococcus aureus;three sheep were implanted with unloaded porous space maintainers and three sheep were implanted with vancomycin-loaded space maintainers within the defect site. During the same surgery, 3D-printed in vivo bioreactors containing autograft or xenograft were implanted adjacent to rib periosteum. After 9 weeks, animals were euthanized, and tissues were analyzed. Antibiotic-loaded space maintainers were able to prevent dehiscence of soft tissue overlying the space maintainer, reduce local inflammatory cells, eliminate the persistence of pathogens, and prevent the increase in mandibular size compared to unloaded space maintainers in this sheep model. Animals with an untreated mandibular infection formed bony tissues with greater density and maturity within the distal bioreactors. Additionally, tissues grown in autograft-filled bioreactors had higher compressive moduli and higher maximum screw pull-out forces than xenograft-filled bioreactors. In summary, we demonstrated that antibiotic-releasing space maintainers are an innovative approach to preserve a robust soft tissue pocket while clearing infection, and that local infections can increase local and remote bone growth.

关键词： biopharmaceutical   butyrylcholinesterase   plant cell culture   semicontinuous   technoeconomic analysis  

摘要： Biopharmaceutical protein production using transgenic plant cell bioreactor processes offers advantages over microbial and mammalian cell culture platforms in its ability to produce complex biologics with simple chemically defined media and reduced biosafety concerns. A disadvantage of plant cells from a traditional batch bioprocessing perspective is their slow growth rate which has motivated us to develop semicontinuous and/or perfusion processes. Although the economic benefits of plant cell culture bioprocesses are often mentioned in the literature, to our knowledge no rigorous technoeconomic models or analyses have been published. Here we present technoeconomic models in SuperPro Designer (R) for the large-scale production of recombinant butyrylcholinesterase (BChE), a prophylactic/therapeutic bioscavenger against organophosphate nerve agent poisoning, in inducible transgenic rice cell suspension cultures. The base facility designed to produce 25 kg BChE per year utilizing two-stage semicontinuous bioreactor operation manufactures a single 400 mg dose of BChE for $263. Semicontinuous operation scenarios result in 4-11% reduction over traditional two-stage batch operation scenarios. In addition to providing a simulation tool that will be useful to the plant-made pharmaceutical community, the model also provides a computational framework that can be used for other semicontinuous or batch bioreactor-based processes.

关键词： Life cycle assessment (LCA)   Sb mine drainage remediation   Energy analysis   Environmental impacts   Passive biological treatment   Adsorption  

摘要： Industrial processes, such as smelting and mining, lead to antimony (Sb) contamination, which poses an environmental and human health risk. In this study, the energy consumption and environmental impacts of a passive biological treatment system were quantitatively evaluated using life cycle assessment (LCA), and the results were compared with that of an adsorption purification system. The results showed that the biosystem had a lower energy consumption compared with the adsorption system, with an energy savings of 27.39%. The environmental impacts of the bioreactor were also lower regarding acidification, ecotoxicity, carcinogens, climate change, resource depletion, and respiratory effects. The construction resulted in the most energy consumption (99%) for the passive bioreactor. Therefore, adopting environmentally friendly construction materials could make the biosystem a more energy-efficient option. Results demonstrated that the bioreactor in this research can have great potential for Sb mine drainage applications in terms of energy savings and environmental remediation without diminishing performance. The study findings can be useful for deciding the most energy effective process for mine drainage remediation. In addition, the identification of the energy and environmental impacts of the processes provide valuable information for the design of future systems that consume less materials and utilize new construction materials.