Aimed at the low ratio of carbon and nitrogen (C/N, approximately 7/1) of waste activated sludge (WAS), which would inhibit the acetogenesis process during anaerobic fermentation, this study ...introduced three brewing wastes, including vinegar (VR), stillage (SR) and soy sauce (SSR) residues, to promote acetogenesis by co-fermenting with WAS. Results showed that different brewing wastes contributed differently to the volatile fatty acids (VFAs) yield. The best performance was observed with SSR (4517 ± 367 mg COD/L), particularly rich in C2–C3 VFAs, corresponding to 40% and 52% higher concentrations than with SR and VR, respectively. Meanwhile, the hydrolysis rate constant peaked at 0.0059 h−1 in the SSR test, compared to the sole WAS test (0.0018 h−1). Furthermore, canonical correlation analysis reflected that the functional consortia, known to ferment saccharides/amino acids into C2–C3 VFAs (i.e., Proteiniclasticum, Petrimonas, Cloacibacillus and Gemmobacter), was related to the characteristics of the feedstock.
Synergistic control of the risks posed by emerging antimicrobials and antibiotic resistance genes (ARGs) is crucial for ensuring ecological safety. Although electrogenic respiration can enhance the ...biodegradation of several antimicrobials and reduce ARGs accumulation, the association mechanisms of antimicrobial biodegradation (trimethoprim, TMP) with the fate of the antimicrobial resistome remain unclear. Here, the biotransformation pathway of TMP, microbial associations, and functional gene profiles (e.g., degradation, antimicrobial resistance, and electron transfer) were analyzed. The results showed that the microbial electrogenic respiration significantly enhanced the biodegradation of TMP, especially with a cosubstrate sodium acetate supply. Electroactive bacteria enriched in the electrode biofilm positively correlated with potential TMP degraders dominated in the planktonic communities. These cross-niche microbial associations may contribute to the accelerated catabolism of TMP and extracellular electron transfer. Importantly, the evolution and dissemination of overall ARGs and mobile genetic elements (MGEs) were significantly weakened due to the enhanced cometabolic biodegradation of TMP. This study provides a promising strategy for the synergistic control of the water ecological risks of antimicrobials and their resistome, while also highlighting new insights into the association of antimicrobial biodegradation with the evolution of the resistome in an electrically integrated biological process.
Antibiotics in waste activated sludge (WAS) has drawn increasing attention because of their persistent and bioaccumulation characteristics. Most study illustrated the role of antibiotics in anaerobic ...fermentation from WAS, but lacking the analysis at microbial level as well as the possible interaction between them. This study investigated the effect of three sulfonamide antibiotics (sulfamethoxazole (SMX), sulfaquinoxaline (SQX), and sulfadiazine (SD)) on WAS fermentation and explored its microbiological mechanism. Results indicated that the production of short-chain fatty acids (SCFAs) was significantly improved by 1.9 folds with a peak value at 4626.1 mg COD L−1 in the existence of SD. This was attributed to the promoted release of soluble proteins and polysaccharides with the existence of sulfonamide antibiotics (SAs) as revealed by the excitation-emission matrix (EEM) spectrum. Analysis of microbial community structure showed that the total abundance of the fermenters in groups with SAs was1.2–1.6 times of that in Control. Specifically, the acid-forming genus Tissierella in SMX and SQX increased by 12.1%–15.0% compared with the Control, while the proteolytic genus Proteinivorax dominated in SD with 39.5%. Molecular ecological networks (MENs) analysis further revealed the potential cooperative relationships among different fermenters. This study was anticipated to provide some valuable information for the behavior of antibiotics in WAS fermentation.
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•The existence of SMX, SQX and SD facilitated SCFAs production from WAS anaerobic fermentation.•The presence of SMX, SQX and SD enhanced the solubility and biodegradability of proteins and polysaccharides.•The abundance of fermenters was increased in fermentation systems containing SMX, SQX and SD.•The potential cooperative relationships were established among the key microbial community.
Persulfate oxidation (PS) is widely employed as a promising alternative for waste activated sludge pretreatment due to the capability of generating free radicals. The product differences and ...microbiological mechanisms by which PS activation triggers WAS digestion through multiple modes need to be further investigated. This study comprehensively investigated the effects of persulfate oxidation activated through multiple modes, i.e., ferrous, zero-valent iron (ZVI), ultraviolet (UV) and heat, on the performance of sludge digestion. Results showed that PS_ZVI significantly accelerated the methane production rate to 12.02 mL/g VSS. By contrast, PS_Heat promoted the sludge acidification and gained the maximum short-chain fatty acids (SCFAs) yield (277.11 ± 7.81 mg COD/g VSS), which was 3.41-fold compared to that in PS_ZVI. Moreover, ferrous and ZVI activated PS achieved the oriented conversion of acetate, the proportions of which took 73% and 78%, respectively. MiSeq sequencing results revealed that PS_Heat and PS_UV evidently enriched anaerobic fermentation bacteria (AFB) (i.e., Macellibacteroides and Clostridium XlVa). However, PS_Ferrous and PS_ZVI facilitated the enrichment of Woesearchaeota and methanogens. Furthermore, molecular ecological network and mantel test revealed the intrinsic interactions among the multiple functional microbes and environmental variables. The homo-acetogens and sulfate-reducing bacterial had potential cooperative and symbiotic relationships with AFB, while the nitrate-reducing bacteria displayed distinguishing ecological niches. Suitable activation modes for PS pretreatments resulted in an upregulation of genes expression responsible for digestion. This study established a scientific foundation for the application of sulfate radical-based oxidation on energy or high value-added chemicals recovery from waste residues.
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•Effect of multiple activated persulfate oxidation on sludge digestion was studied.•Heat and UV activated persulfate effectively promoted the accumulation of SCFAs.•ZVI and Ferrous activated persulfate were beneficial for methane production.•Microbial community structures were altered by multiple persulfate activation modes.•Suitable activation modes for persulfate upregulated the critical genes expression.
Waste activated sludge (WAS) is a promising phosphorus (P) source for fertilizer production; however, it is mainly enmeshed inside microbial cells or extracellular polymeric matrixes. Thus, efficient ...P release is a key goal. This study provided an effective route to simultaneously release organic P (OP) and harvest hydrogen from WAS via bio-electrolysis assisted with prefermentation system (AD_MEC). The clarification of P fractions in both solid and liquid phases and the underlying mechanism in this cascading system were explored. Free nitrous acid (FNA) was employed to enhance WAS hydrolysis. The results showed that hydrogen generation was effectively accelerated: 0.54 mL per gram sludge (in volatile suspended solids (VSS)) was produced from raw WAS (AD_MEC_RWAS), which increased to 1.27 mL/g VSS from FNA-pretreated WAS (AD_MEC_FWAS). The limited OP release by prefermentation was enhanced via MECs; additionally, it was further promoted by FNA, and the treatment time was also shortened. The maximum OP release efficiency reached 54.6% at 112 h (AD_MEC_FWAS). Additionally, non-apatite and inorganic apatite P may regenerate in MECs due to the localized decrease in pH caused by hydrogen generation. This work may provide a scientific basis to enhance P and hydrogen co-recovery from WAS in forthcoming implementation.
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•H2 recovery and P release from WAS was achieved in cascading conversion system.•The limited OP release in prefermentation was accelerated via bio-electrolysis.•FNA played a positive effect on H2 recovery and OP release from WAS.•Underlying mechanism of cascading conversion system for P release was explored.
MG53 is transcriptionally activated by the IRS‐1/PI3K/AKT signal pathway, which is closely related with oncogenesis of several tumors. Here, the role of MG53 in the tumorigenesis of tongue cancer is ...analyzed in vitro and in vivo. The stable MG53 overexpression/knockdown SCC9 and SCC25 cells are constructed through retrovirus infection. Then a PLGA cylinder is used to provide a 3D culture environment for cell growth. Cell counting results suggest that overexpression of MG53 inhibits the cell proliferation and colony formation of SCC9 and SCC25 cells. While knockdown of MG53 has the opposite effect. Furthermore, knockdown of MG53 significantly promotes the invasion of SCC9 and SCC25 cells. Western blotting data confirm that MG53 affects the expression of the AKT signaling pathway. In a xenograft assay, knockdown of MG53 promotes the growth of xenograft which is induced by SCC25 cells in nude mice. The findings demonstrate that MG53 affects the biological behavior of human tongue cancer SCC9 and SCC25 cells.
A PLGA cylinder, which provides 3D culture environment for cells, is used to determine the proliferation changes of human tongue cancer SCC9 and SCC25 cells induced by MG53. Knockdown of MG53 not only increases the growth of tongue cancer cells but also promotes their invasive ability. A xenograft assay also reaches the same conclusion.
Along with the rapid development of electric vehicles over the past decades, the dominating charging method, fixed charging could not satisfy the increasing need, especially in urban areas with huge ...populations. Mobile charging is thus proposed to solve this problem. In this work, the concept of mobile charging is explained. The user convenience and expenses between the conventional fixed charging piles and the mobile charging piles are compared using a mathematical model. The economic competitiveness of mobile charging is also compared with its counterpart. The results show that, different from fixed charging, mobile charging helps the users save their time wasted in a charging station when their electric vehicles are being charged. Taking the cost of time into consideration, mobile charging can be more economic than fixed charging for many users. Moreover, our model analyses reveal that, under the condition of low utilization rate of fixed charging piles, the levelized cost of electricity for mobile charging piles is much less. Besides, the land cost also plays a role; when it increases, mobile charging piles could be even more economically competitive.
•A mobile charging system for electric vehicles is introduced.•A demonstration project is performed in the urban areas of Xiamen.•User conveniences and expenses by mobile charging are analyzed.•A modified LCOE of mobile charging and fixed charging is studied.
Thin-film composite (TFC) membranes have been widely used in water purification, seawater desalination and waste treatment, etc. The interface between a support layer and a selective skin layer not ...only plays a crucial role in the separation performance of membrane but also regulate the formation of the selective layer. Herein, we report an interlayer enhanced TFC membrane with an interlayer composed of self-doping sulfonated polyaniline (SPANI) nanofibers which possess both excellent hydrophilicity and unique chemical properties. The surface properties prior to the interfacial polymerization (IP) process can be readily tuned by adding different kinds of alkaline solutions to the SPANI interlayer, forming skin layers with various morphology in the subsequent IP process. By simply adding NaHCO3 to the SPANI interlayer, a thin and defect-free polyamide (PA) selective layer with dual morphology of crumple and nanobubble structures can be formed. The optimal i-TFC-NaHCO3-3 membrane shows excellent permeate flux of 35.35 ± 1.35 L m−2 h−1 bar−1 with good capacities of retention for both Na2SO4 (98.95 ± 0.29%) and MgSO4 (95.37 ± 0.43%). This work provides a facile route to enhance the membrane performance by simply adjusting the chemical properties of membrane interlayers.
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•Sulfonated polyaniline (SPANI) nanofibers have been constructed as an interlayer of i-TFC membrane.•The i-TFC membrane with SPANI interlayer can form a PA layer with dual morphology of crumple and nanobubble structures.•Analyze the effect of SPANI alkaline solutions on membrane morphology, separation performance and antifouling propensity.•A profound understanding of the application of SPANI interlayer strategy to construct NF membranes has been proposed.
Conventional nanofiltration (NF) thin-film composite (TFC) membranes are strongly restricted by the trade-off between their water permeance and selectivity as well as the poor structural stability ...for desalination and wastewater treatment. Herein, we report an interlayer-based thin-film composite (i-TFC) NF membrane with high performance using amino-functionalized EMT zeolite (EMT-NH 2) nanocrystals as the interlayer. By adjusting the distribution density of EMT-NH 2 on the substrate, a thin and dense PA layer with heterogeneity multi-level morphology (nanosized nodules and nanoscale stripes) can be formed and regulated. The EMT-NH 2 zeolite nanocrystals with numerous hydrophilic groups (hydroxy and amino groups) and internal cavities can provide an additional priority water channel, increase the amine monomer storage on the substrate, and slow down the diffusion of amine monomer, thereby leading to the construction of a dense PA layer with high performance. As a result, the i-TFC-15 membrane depicted a water permeability of 13.82 ± 0.47 L m-2 h-1 ⋅bar-1 (2.5 times that of the controlled one), while maintaining an excellent retention ability for divalent salts (98.55% for Na 2 SO 4 , 98.42% for MgSO 4 and 97.40% for MgCl 2). Additionally, the rigid hydrophilic interlayer containing zeolite nanocrystals endowed the i-TFC-15 membrane with excellent pressure resistance (up to 2.4 MPa), long-term operating stability, and antifouling propensity (flux-recovery ratio, 90.1%). This work provides an approach for fabricating a novel high-performance NF membrane and deepens our understanding of the role of porous interlayer affecting the formation of the PA layer.
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