Sulfamethoxazole(SMX)is an antibiotic and widely present in aquatic environments,so it presents a serious threat to human health and sustainable development.A dielectric barrier discharge(DBD)plasma jet was utilized t...Sulfamethoxazole(SMX)is an antibiotic and widely present in aquatic environments,so it presents a serious threat to human health and sustainable development.A dielectric barrier discharge(DBD)plasma jet was utilized to degrade aqueous SMX,and the effects of various operating parameters(working gas,discharge power,etc)on SMX degradation performance were studied.The experimental results showed that the DBD plasma jet can obtain a relatively high degradation efficiency for SMX when the discharge power is high with an oxygen atmosphere,the initial concentration of SMX is low,and the aqueous solution is under acidic conditions.The reactive species produced in the liquid phase were detected,and OH radicals and O3were found to play a significant role in the degradation of SMX.Moreover,the process of SMX degradation could be better fitted by the quasi-first-order reaction kinetic equation.The analysis of the SMX degradation process indicated that SMX was gradually decomposed and 4-amino benzene sulfonic acid,benzene sulfonamide,4-nitro SMX,and phenylsulfinyl acid were detected,and thus three possible degradation pathways were finally proposed.The mineralization degree of SMX reached 90.04%after plasma treatment for 20 min,and the toxicity of the solution fluctuated with the discharge time but eventually decreased.展开更多
Molecularly imprinted polymers(MIPs)exhibit high selectivity resulting from imprinted cavities and superior performance from functional materials,which have attracted much attention in many fields.However,the combinat...Molecularly imprinted polymers(MIPs)exhibit high selectivity resulting from imprinted cavities and superior performance from functional materials,which have attracted much attention in many fields.However,the combination of MIPs film and functional materials is a great challenge.In this study,hemin/graphene hybrid nanosheets(H-GNs)were used to initiate the imprinted polymerization by catalyzing the generation of free radicals.Thus,MIPs using sulfamethoxazole as the template was directly prepared on the surface of H-GNs without any film modification.Most importantly,the template could be absorbed on the H-GNs to enhance the number of imprinted sites per unit surface area,which could improve the selectivity of MIPs film.Thus,the composites could exhibit high adsorption capacity(29.4 mg/g),imprinting factor(4.2)and excellent conductivity,which were modified on the surface of electrode for rapid,selective and sensitive detection of sulfamethoxazole in food and serum samples.The linear range was changed from 5μg/kg to 1 mg/g and the limit of detection was 1.2μg/kg.This sensor was free from interference caused by analogues of sulfamethoxazole,which provides a novel insight for the preparation of MIPs-based sensor and its application in food safety monitoring and human exposure study.展开更多
The wide application of antibiotics in aquaculture requires an efficient treatment of the wastewater before discharging it into the environment.During the wastewater treatment,the influence of antibiotics on the perfo...The wide application of antibiotics in aquaculture requires an efficient treatment of the wastewater before discharging it into the environment.During the wastewater treatment,the influence of antibiotics on the performance of bioreactor should be well revealed due to their toxicity to the functional microbial community.In this study,the effect of feeding 10-30 mg L−1 sulfamethoxazole(SMX)in influent on the performance of an anoxic/oxic-moving bed biofilm reactor(A/O-MBBR)treating mariculture wastewater and the responding change of biofilm microbial communities was investigated.The COD average removal rate remained at 94.61%-97.34%with the dosage of SMX.Compared with that,the nitrifying removals of NH4+-N and NO2−-N were violently inhibited by 30 mg L−1 SMX and denitrifying removal of the NO3−-N decreased obviously with 20 mg L−1 or more SMX.The microbial community in the successful startup bioreactor was relatively abundant,while the diversity of microbial community decreased with the increase of feeding SMX.The salt-tolerant and SMX-resistant genera Arcobacter,Thiothrix,Desulfuromusa and Nitrosomonas were gradually enriched and finally played a vital role in converting COD and recycling nitrogen and sulfur.Hence,the present A/O-MBBR reactor with the salt-tolerant functional microbiota achieved efficient removal of pollutants in the presence of low concentration(e.g.,10 mg L−1)SMX.展开更多
The illegal use of veterinary drugs has led to the occurrence of residues in food of animal origin.This is a hazard to people's health.In this paper,a sensitive and fast assay was developed to determine sulfametho...The illegal use of veterinary drugs has led to the occurrence of residues in food of animal origin.This is a hazard to people's health.In this paper,a sensitive and fast assay was developed to determine sulfamethoxazole (SMOZ) in PBS with a homemade surface plasmon resonance (SPR)-based biosensor which had a single flow channel and two references.The derivative of SMOZ was covalently immobilized to a carboxymethyldextran modified gold film.A recently developed monoclonal antibody against sulfamethoxazole was used to develop an inhibitive immunobiosensor assay in which the antibody was mixed with SMOZ of different concentrations prepared with PBS to construct a standard curve with a low limit of detection(LOD).The effect of matrix in milk was also studied.Calculating of the apparent concentration showed the cross-reactivity with other sulfonamides.展开更多
Objective: To compare bioi lm formation in trimethoprim/sulfamethoxazole(SXT)-susceptible Escherichia coli(E. coli)(SSEC) and SXT-resistant E. coli(SREC) isolated from patients with urinary tract infections, and study...Objective: To compare bioi lm formation in trimethoprim/sulfamethoxazole(SXT)-susceptible Escherichia coli(E. coli)(SSEC) and SXT-resistant E. coli(SREC) isolated from patients with urinary tract infections, and study the motile ability and physical characteristics of the isolates.Methods: A total of 74 E. coli isolates were tested for antimicrobial susceptibility with the disc diffusion assay. Based on the SXT-susceptibility test, the E. coli isolates were divided into SSEC(N = 30) and SREC(N = 44) groups. All E. coli isolates were examined for motile ability by using a motility test medium, and for checking bioi lm formation a scanning electron microscope was used. Bacterial colony size was measured with a vernier caliper and bacterial cell length was measured under a light microscope. The bacterial growth rate was studied by plotting the cell growth(absorbance) versus the incubation time. Results: The frequencies of non-motility and biofilm formation in the SREC group were signii cantly higher than that in the SSEC group(P < 0.01). The SREC bacterial cell length was shorter than that in the SSEC group [(1.35 ± 0.05) vs.(1.53 ± 0.05) μm, P < 0.05)], whereas the bacterial colony size and mid-log phase of the growth curve were not signii cantly dif erent. Conclusions: The present study indicated that bioi lm formation and phenotypic change of uropathogenic E. coli can be attributed to the mechanism of E. coli SXT resistance.展开更多
In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration sho...In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration showed negligible effect on efficiencies for removal of nitrate and COD.However,the ammonium ions removal rate was moderately reduced,when the influent SMX concentration in wastewater reached 6 mg/L.Total nitrogen removal efficiency remained as high as 76.77%towards the day 158 at the end of experiment.Candidatus_Brocadia and Candidatus_Kuenenia were the functional anammox strains.The unclassified_f__Rhodobacteraceae sp.was predominant heterotrophic denitrifying strain in the studied reactor.The concentrations of soluble extracellular polymeric substances in sludge obviously increased from 16.76 mg/g VSS to 32.31 mg/g VSS,which might protect the nitrogen removal strains from high-concentration SMX.This result provides a theoretical and technical foundation for the application of denitrifying ammonium oxidation process in treating sulfamethoxazole-laden secondary wastewater effluent.展开更多
Our previous study suggested that the production of superantigens and heat-shock protein 60 by small intestinal bacteria might play a role in Kawasaki disease (KD). We demonstrated that they were all resistant to comm...Our previous study suggested that the production of superantigens and heat-shock protein 60 by small intestinal bacteria might play a role in Kawasaki disease (KD). We demonstrated that they were all resistant to commonly used antibiotics, except for sulamethoxazole trimethoprim (SMX-TMP). We used SMX-TMP for 7 cases of KD that were unresponsive to intravenous immunoglobulin (IVIG) and studied the antipyretic potency of this treatment. In 6 out of the 7 cases, we demonstrated that antipyretic potency was observed without side effects within 2 days of the initial administration. Antimicrobial therapy using SMX-TMP might represent a novel strategy for cases of KD that are unresponsive to IVIG.展开更多
Nanoporous Carbon (NPC) with high surface area of 1379 M2/G and high proportion of micropore and mesopore volume of 2.90 Cm3/G was prepared by carbonization of metal?organic frameworks ZIF-8. The adsorption of NPC tow...Nanoporous Carbon (NPC) with high surface area of 1379 M2/G and high proportion of micropore and mesopore volume of 2.90 Cm3/G was prepared by carbonization of metal?organic frameworks ZIF-8. The adsorption of NPC towards the representative sulfonamide antibiotics sulfamethoxazole (SMX) from aqueous solutions was explored, in comparison with powder active carbon (AC). The adsorption kinetics and isotherms showed that the maximum adsorption capacity (Qm) of NPC toward SMX was 757 Mg/G, around 2 times than that of AC adsorption. The high adsorption affinity of NPC was related to the high surface area and special Mic/Mesopore structure. The pore-filling mechanism as well as electrostatic interaction had important influence on the high adsorption of NPC. The results implied that nanoporous carbon derived from mofs could remove the contaminants from aqueous solutions effectively, and would be a promising adsorbent for the removal of contaminants in the future.展开更多
<strong>Background:</strong> Sulfamethoxazole/Trimethoprim is a commonly used drug in a variety of clinically indicated scenarios, but it is not without side effect. Case-reports have stated that adverse r...<strong>Background:</strong> Sulfamethoxazole/Trimethoprim is a commonly used drug in a variety of clinically indicated scenarios, but it is not without side effect. Case-reports have stated that adverse reactions secondary to Sulfamethoxazole/Trimethoprim can present very early in the course of treatment, especially in patients who have a higher predisposition. Thus, the burden is placed on the clinician to be wary of these side effects and be able to recognize them in the correct clinic scenario. Objective: To discuss the risk of developing cholestatic hepatic dysfunction secondary to treatment with sulfamethoxazole/trimethoprim. <strong>Methods:</strong> We present the history, physical findings, laboratory investigations, and clinical course of a 47-year-old African-American female who developed cholestatic hepatic dysfunction after treatment with sulfamethoxazole/trimethoprim for pyelonephritis. <strong>Results:</strong> Drug-induced liver injury is a rare complication of sulfamethoxazole/trimethoprim therapy and only 20% of cases are secondary to cholestatic hepatic dysfunction. Our patient, who had been on sulfamethoxazole/trimethoprim for 7 days for pyelonephritis, presented to our hospital with a clinical picture consistent with hepatic injury;her laboratory investigations were noteworthy for an elevated white blood cell count, platelet count, and elevated transaminases, along with alkaline phosphatase levels greater than 2 times the upper limit of normal. Promptly following the discontinuation of sulfamethoxazole/trimethoprim, our patient improved clinically and her liver enzymes down-trended during the course of her hospital stay. She returned to normal at her 4 month follow up, thus confirming the diagnosis of cholestatic hepatic dysfunction secondary to sulfamethoxazole/trimethoprim. <strong>Conclusion:</strong> Cholestatic hepatic dysfunction is a form of drug-induced liver injury and a rare complication of sulfamethoxazole/trimethoprim treatment. The majority of cases resolve following discontinuation of the offending medication. However, a small percentage of patients may progress to liver failure and ultimately require liver transplantation. Clinicians should be aware of these risks to avoid delaying the discontinuation of sulfamethoxazole/trimethoprim.展开更多
Sulfamethoxazole-trimethoprim (TMP-SMX)-induced rhabdomyolysis is a rare complication of a commonly used antibiotic. This is a case report of a 43-year old immunocompetent African American woman with a history of depr...Sulfamethoxazole-trimethoprim (TMP-SMX)-induced rhabdomyolysis is a rare complication of a commonly used antibiotic. This is a case report of a 43-year old immunocompetent African American woman with a history of depression and chronic alcohol consumption who presented to the emergency department (ED) with worsening bilateral leg pain. Before presentation, the patient was prescribed a twice daily dose of TMP-SMX for a urinary tract infection. The patient reported the development of intensifying leg pain after taking five doses of TMP-SMX. On presentation to the ED she was hemodynamically stable, afebrile, and leg pain intensity 10 out of 10. The patient admitted to daily alcohol consumption and taking vortioxetine 10 mg per day for treatment of depression. Initial labs drawn in the ED showed an elevated creatine kinase (CK) of 26,231 U/L and a normal serum creatinine (SCr) of 1 mg/dL. Through patient history and laboratory tests, common causes of rhabdomyolysis were ruled out. Treatment was initiated with IV fluids plus thiamine and folic acid supplementation, TMP-SMX was discontinued, and vortioxetine 10 mg per day was continued until hospital day five. The patient began to show improvement in lower extremity pain and tenderness and was discharged on hospital day eight with minimal residual leg pain and a CK of 2809 U/L. This case report presents only the third incidence of an immunocompetent patient developing TMP-SMX-induced rhabdomyolysis. This case highlights an opportunity for a pharmacist’s intervention and the need for future research to determine risk factors of TMP-SMX-induced rhabdomyolysis in immunocompetent patients.展开更多
Objectives: To determine the mutant prevention concentration (MPC) of sulfamethoxazole-trimethoprim (SXT) alone and in combination with levofloxacin (LVX) against Stenotrophomonas maltophilia (S. maltophilia) and to d...Objectives: To determine the mutant prevention concentration (MPC) of sulfamethoxazole-trimethoprim (SXT) alone and in combination with levofloxacin (LVX) against Stenotrophomonas maltophilia (S. maltophilia) and to determine if the combination may decrease the emergence of resistant mutants. Methods: The MPC with 20 S. maltophilia strains which were both susceptible to SXT and LVX were determined by inhibiting visible growth among 1010 CFU on four agar plates after 72 hours incubation at 37°C. Results: All except two strains (18/20) showed a mutant prevention concentration ≥ 152/8 μg/mL for SXT and the range of the mutant prevention concentration for the SXT in combination with LVX is 9.5/0.5~608/32 μg/mL, which demonstrates at least 2 fold reduction except one strain. There was a significant difference (P < 0.01) between SXT alone and in combination with LVX on the mutant prevention concentration and mutant prevention concentration/minimum inhibitory concentration values. Conclusions: The MPC/MIC values were narrowed for SXT by combining with LVX against the S maltophilia. The combination may decrease the enrichment of mutant bacterial populations. Much study is needed to verify whether the using of drug combinations may restrict or even block the selection of S. maltophilia mutants.展开更多
Trimethoprim-Sulfamethoxazole (TMP-SMZ) is associated with severe hepatic toxicity or liver failure. We present a case of severe hepatic toxicity for whom TMP-SMZ was prescribed as part of treatment for mixed connecti...Trimethoprim-Sulfamethoxazole (TMP-SMZ) is associated with severe hepatic toxicity or liver failure. We present a case of severe hepatic toxicity for whom TMP-SMZ was prescribed as part of treatment for mixed connective tissue disease (MCTD). TMP-SMZ was used to prevent complications from steroid therapy, but fever and hepatic toxicity developed with repeated TMP-SMZ medication. While the drug lymphocyte stimulation test (DLST) for TMP-SMZ showed negative, the genotype for N-acetyltransferase 2 (NAT2) showed type *6/*7, which is the slow acetylating type for NAT2 activity. This finding for NAT2 genotype and the patient’s clinical history lead us to speculate that her fever and hepatic toxicity were caused by TMP-SMZ.展开更多
The pharmacokinetic profi les and sulfamethoxazole(SMX) acetylation process in turbot reared at 18°C were investigated. Either SMX(parent drug) or its acetylized metabolite, N4-acetylsulfamethoxazole(Ac SMX), was...The pharmacokinetic profi les and sulfamethoxazole(SMX) acetylation process in turbot reared at 18°C were investigated. Either SMX(parent drug) or its acetylized metabolite, N4-acetylsulfamethoxazole(Ac SMX), was administered intravascularly to turbot at a dosage of 50 mg/kg BW. Serum concentrations of the parent drug and its metabolite were both measured by HPLC, and the changes in concentration over time were analyzed in two- and non-compartment models because SMX treatment produced multiple peaks. The results demonstrated that the elimination half-life of the parent drugs, SMX and Ac SMX, were 159.2 and 5.9 h, respectively. The apparent volume of distribution was 0.2 and 0.8 L/kg, and the clearance was 0.038 and 0.222 L/(h·kg), for SMX and Ac SMX, respectively. SMX acetylation in turbot was 2.8%, and the deacetylation of Ac SMX was 0.2%. These fi ndings may be useful in optimizing SMX dosage regimens in turbot aquaculture.展开更多
This study was designed to examine the interaction of sulfamethoxazole(SMZ) with human serum albumin(HSA).Spectroscopic analysis of the emission quenching at different temperatures revealed that the quenching mechanis...This study was designed to examine the interaction of sulfamethoxazole(SMZ) with human serum albumin(HSA).Spectroscopic analysis of the emission quenching at different temperatures revealed that the quenching mechanism of human serum albumin by SMZ was static mechanism.The binding constant values for the SMZ-HSA system were obtained to be 22,500 L/mol at 288 K,15,600 L/mol at 298 K,and 8500 L/mol at 308 K.The distance r between donor and acceptor was evaluated according to the theory of Foster energy transfer.The results of spectroscopic analysis and molecular modeling techniques showed that the conformation of human serum albumin had been changed in the presence of SMZ.The thermodynamic parameters,namely enthalpy change(△H^0)-36.0 kJ/mol,entropy change(△S^0)-41.3 J/mol K and free energy change(△G^0)-23.7 kJ/mol,were calculated by using van't Hoff equation.The effect of common ions on the binding of SMZ to HSA was tested.展开更多
A homemade array surface plasmon resonance (SPR)-based imaging biosensor was used to develop sensitive and fast immunoassays to determine sulfamethoxazole (SMOZ) and sulfamethazine (SMT) in buffer. Two conjugations of...A homemade array surface plasmon resonance (SPR)-based imaging biosensor was used to develop sensitive and fast immunoassays to determine sulfamethoxazole (SMOZ) and sulfamethazine (SMT) in buffer. Two conjugations of sulfonamide-bovine serum albumin (BSA) were separately immobilized on two different rows of the array chip with one row as reference. The immobilization was carried out in the instrument to monitor the quantity of the conjugations immobilized. The antibody mixed with the sulfonamide in the buffer was injected over the surface of the chip to get a relative response which was inversely proportional to the concentration of the sulfonamide in the PBS buffer. Two calibration curves were constructed and the limit of detection for sufamethoxazole in buffer was 3.5 ng/mL and for sulfamethazine 0.6 ng/mL. The stability and specificity of the antibody were also studied. The monoclonal antibody did not bind with BSA.展开更多
A new indirect inhibitive immunoassay using surface plasmon resonance(SPR) coupled with molecularly imprinted polymer(MIP) was developed.A sulfamethoxazole(SMX) MIP coating capillary was produced and used as an in-tub...A new indirect inhibitive immunoassay using surface plasmon resonance(SPR) coupled with molecularly imprinted polymer(MIP) was developed.A sulfamethoxazole(SMX) MIP coating capillary was produced and used as an in-tube solid phase extraction(SPE) device.The MIP coating formed a nanometer film on the inner wall of the capillary.The anti-SMX mono-antibody was inhibited by SMX extracted by the MIP coating in a dose-dependent manner.The calibration curve was generated by linear fit over the range of 0.04-10.00 ng/mL.The limit of detection was 0.01 ng/mL.This method has high sensitivity and can be performed automatically.展开更多
It has been documented that organic contaminants can be degraded by hydroxyl radicals(•OH)produced by the activation of H2O2 by Fe(II)-bearing clay.However,the interfacial electron transfer reactions between structura...It has been documented that organic contaminants can be degraded by hydroxyl radicals(•OH)produced by the activation of H2O2 by Fe(II)-bearing clay.However,the interfacial electron transfer reactions between structural Fe(Ⅱ)and H_(2)O_(2) for•OH generation and its effects on contaminant remediation are unclear.In this study,we first investigated the relation between•OH generation sites and sulfamethoxazole(SMX)degradation by activating H2O2 using nontronite with different reduction extents.SMX(5.2–16.9μmol/L)degradation first increased and then decreased with an increase in the reduction extent of nontronite from 22% to 62%,while the•OH production increased continually.Passivization treatment of edge sites and structural variation results revealed that interfacial electron transfer reactions between Fe(Ⅱ)and H2O2 occur at both the edge and basal plane.The enhancement on basal plane interfacial electron transfer reactions in a high reduction extent rNAu-2 leads to the enhancement on utilization efficiencies of structural Fe(Ⅱ)and H_(2)O_(2) for•OH generation.However,the•OH produced at the basal planes is less efficient in oxidizing SMX than that of at edge sites.Oxidation of SMX could be sustainable in the H_(2)O_(2)/rNAu-2 system through chemically reduction.The results of this study show the importance role of•OH generation sites on antibiotic degradation and provide guidance and potential strategies for antibiotic degradation by Fe(Ⅱ)-bearing clay minerals in H2O2-based treatments.展开更多
A novel hierarchical bowl-like FeCuS@Cu_(2)S@Fe^(0)nanohybrid catalyst(B-FeCuS@Cu_(2)S@Fe^(0))was synthesized for removing sulfamethoxazole(SMX) through catalytic activation of peroxymonosulfate(PMS). It was found tha...A novel hierarchical bowl-like FeCuS@Cu_(2)S@Fe^(0)nanohybrid catalyst(B-FeCuS@Cu_(2)S@Fe^(0))was synthesized for removing sulfamethoxazole(SMX) through catalytic activation of peroxymonosulfate(PMS). It was found that this catalyst exhibited excellently high catalytic activity. Under optimized reaction conditions, all the added SMX(12 mg/L) could be completely degraded within 5 min. The SMX degradation followed pseudo first order kinetics with a rate constant k of 0.89 min^(-1), being 1.38, 4.51, 8.99 and 35.6 times greater than that of other catalysts including Fe^(0)(0.644 min^(-1)in the very initial stage), bowl-like iron-doped CuS(B-FeCuS, 0.197 min^(-1)), bowl-like CuS(B-CuS, 0.099 min^(-1)) and Cu_(2)O(0.025 min^(-1)), respectively. During the degradation, several reactive oxygen species(·OH, SO_(4)·-and1O_(2)) were generated with ·OH as the main one as confirmed by electron paramagnetic resonance analysis. The SMX degradation in the present system included both radical and non-radical mediated processes. A possible mechanistic insight of the PMS activation by bowl Fe^(0)decorated CuS@Cu_(2)S-based catalyst was proposed according to X-ray photoelectron spectroscopic(XPS) analysis, and the degradation pathway of SMX was speculated by monitoring the degradation intermediates with liquid chromatography coupled with mass spectrometry(LC-MS).展开更多
To understand the long-term performance of bioretention systems under sulfamethoxazole (SMX) stress, an unplanted bioretention system (BRS) and two modified BRSs with coconut-shell activated carbon (CAC) and CAC/zero-...To understand the long-term performance of bioretention systems under sulfamethoxazole (SMX) stress, an unplanted bioretention system (BRS) and two modified BRSs with coconut-shell activated carbon (CAC) and CAC/zero-valent-iron (Fe^(0)) granules (CAC-BRS and Fe/CAC-BRS) were established. Both CAC-BRS and Fe/CAC-BRS significantly outperformed BRS in removing total nitrogen (TN)(CAC-BRS:82.48%;Fe/CAC-BRS:78.08%;BRS:47.51%), total phosphorous (TP)(CAC-BRS:79.36%;Fe/CAC-BRS:98.26%;BRS:41.99%),and SMX (CAC-BRS:99.74%, Fe/CAC-BRS:99.80%;BRS:23.05%) under the long-term SMX exposure (0.8 mg/L, 205 days). High-throughput sequencing revealed that the microbial community structures of the three BRSs shifted greatly in upper zones after SMX exposure.Key functional genera, dominantly Nitrospira, Rhodoplanes, Desulfomicrobium, Geobacter,were identified by combining the functional prediction by the FAPROTAX database with the dominant genera. The higher abundance of nitrogen functional genes (nirK, nirS and nos Z) in CAC-BRS and Fe/CAC-BRS might explain the more efficient TN removal in these two systems. Furthermore, the relative abundance of antibiotic-resistant genes (ARGs)sul I and sulII increased in all BRSs along with SMX exposure, suggesting the selection of bacteria containing sul genes. Substrates tended to become reservoirs of sul genes. Also,co-occurrence network analysis revealed distinct potential host genera of ARGs between upper and lower zones. Notably, Fe/CAC-BRS succeeded to reduce the effluent sul genes by1-2 orders of magnitude, followed by CAC-BRS after 205-day exposure. This study demon-strated that substrate modification was crucial to maintain highly efficient nutrients and SMX removals, and ultimately extend the service life of BRSs in treating SMX wastewater.展开更多
The impact of antibiotics on the environmental protection and sludge treatment fields has been widely studied.The recovery of hydrogen from waste activated sludge(WAS)has become an issue of great interest.Nevertheless...The impact of antibiotics on the environmental protection and sludge treatment fields has been widely studied.The recovery of hydrogen from waste activated sludge(WAS)has become an issue of great interest.Nevertheless,few studies have focused on the impact of antibiotics present in WAS on hydrogen production during dark anaerobic fermentation.To explore the mechanisms,sulfamethoxazole(SMX)was chosen as a representative antibiotic to evaluate how SMX influenced hydrogen production during dark anaerobic fermentation of WAS.The results demonstrated SMX promoted hydrogen production.With increasing additions of SMX from 0 to 500 mg/kg TSS,the cumulative hydrogen production elevated from 8.07±0.37 to 11.89±0.19 mL/g VSS.A modified Gompertz model further verified that both the maximum potential of hydrogen production(Pm)and the maximum rate of hydrogen production(R_(m))were promoted.SMX did not affected sludge solubilization,but promoted hydrolysis and acidification processes to produce more hydrogen.Moreover,the methanogenesis process was inhibited so that hydrogen consumption was reduced.Microbial community analysis further demonstrated that the introduction of SMX improved the abundance of hydrolysis bacteria and hydrogen-volatile fatty acids(VFAs)producers.SMX synergistically influenced hydrolysis,acidification and acetogenesis to facilitate the hydrogen production.展开更多
基金supported jointly by National Natural Science Foundation of China(Nos.U20A20372,51807046,51777206)the Natural Science Foundation of Anhui Province(Nos.2108085MD136,1908085MA29)。
文摘Sulfamethoxazole(SMX)is an antibiotic and widely present in aquatic environments,so it presents a serious threat to human health and sustainable development.A dielectric barrier discharge(DBD)plasma jet was utilized to degrade aqueous SMX,and the effects of various operating parameters(working gas,discharge power,etc)on SMX degradation performance were studied.The experimental results showed that the DBD plasma jet can obtain a relatively high degradation efficiency for SMX when the discharge power is high with an oxygen atmosphere,the initial concentration of SMX is low,and the aqueous solution is under acidic conditions.The reactive species produced in the liquid phase were detected,and OH radicals and O3were found to play a significant role in the degradation of SMX.Moreover,the process of SMX degradation could be better fitted by the quasi-first-order reaction kinetic equation.The analysis of the SMX degradation process indicated that SMX was gradually decomposed and 4-amino benzene sulfonic acid,benzene sulfonamide,4-nitro SMX,and phenylsulfinyl acid were detected,and thus three possible degradation pathways were finally proposed.The mineralization degree of SMX reached 90.04%after plasma treatment for 20 min,and the toxicity of the solution fluctuated with the discharge time but eventually decreased.
文摘Molecularly imprinted polymers(MIPs)exhibit high selectivity resulting from imprinted cavities and superior performance from functional materials,which have attracted much attention in many fields.However,the combination of MIPs film and functional materials is a great challenge.In this study,hemin/graphene hybrid nanosheets(H-GNs)were used to initiate the imprinted polymerization by catalyzing the generation of free radicals.Thus,MIPs using sulfamethoxazole as the template was directly prepared on the surface of H-GNs without any film modification.Most importantly,the template could be absorbed on the H-GNs to enhance the number of imprinted sites per unit surface area,which could improve the selectivity of MIPs film.Thus,the composites could exhibit high adsorption capacity(29.4 mg/g),imprinting factor(4.2)and excellent conductivity,which were modified on the surface of electrode for rapid,selective and sensitive detection of sulfamethoxazole in food and serum samples.The linear range was changed from 5μg/kg to 1 mg/g and the limit of detection was 1.2μg/kg.This sensor was free from interference caused by analogues of sulfamethoxazole,which provides a novel insight for the preparation of MIPs-based sensor and its application in food safety monitoring and human exposure study.
基金the Fundamental Research Funds for the Central Universities of China(No.201964004)the National Natural Science Foundation of China(No.41977315).
文摘The wide application of antibiotics in aquaculture requires an efficient treatment of the wastewater before discharging it into the environment.During the wastewater treatment,the influence of antibiotics on the performance of bioreactor should be well revealed due to their toxicity to the functional microbial community.In this study,the effect of feeding 10-30 mg L−1 sulfamethoxazole(SMX)in influent on the performance of an anoxic/oxic-moving bed biofilm reactor(A/O-MBBR)treating mariculture wastewater and the responding change of biofilm microbial communities was investigated.The COD average removal rate remained at 94.61%-97.34%with the dosage of SMX.Compared with that,the nitrifying removals of NH4+-N and NO2−-N were violently inhibited by 30 mg L−1 SMX and denitrifying removal of the NO3−-N decreased obviously with 20 mg L−1 or more SMX.The microbial community in the successful startup bioreactor was relatively abundant,while the diversity of microbial community decreased with the increase of feeding SMX.The salt-tolerant and SMX-resistant genera Arcobacter,Thiothrix,Desulfuromusa and Nitrosomonas were gradually enriched and finally played a vital role in converting COD and recycling nitrogen and sulfur.Hence,the present A/O-MBBR reactor with the salt-tolerant functional microbiota achieved efficient removal of pollutants in the presence of low concentration(e.g.,10 mg L−1)SMX.
基金The authors greatly acknowledge the financial support from the National Science Foundation of China （grant number 60427001 and 60302003）.
文摘The illegal use of veterinary drugs has led to the occurrence of residues in food of animal origin.This is a hazard to people's health.In this paper,a sensitive and fast assay was developed to determine sulfamethoxazole (SMOZ) in PBS with a homemade surface plasmon resonance (SPR)-based biosensor which had a single flow channel and two references.The derivative of SMOZ was covalently immobilized to a carboxymethyldextran modified gold film.A recently developed monoclonal antibody against sulfamethoxazole was used to develop an inhibitive immunobiosensor assay in which the antibody was mixed with SMOZ of different concentrations prepared with PBS to construct a standard curve with a low limit of detection(LOD).The effect of matrix in milk was also studied.Calculating of the apparent concentration showed the cross-reactivity with other sulfonamides.
基金Supported by Incubation Research Project-2012 grant,Khon Kaen University,Thailand
文摘Objective: To compare bioi lm formation in trimethoprim/sulfamethoxazole(SXT)-susceptible Escherichia coli(E. coli)(SSEC) and SXT-resistant E. coli(SREC) isolated from patients with urinary tract infections, and study the motile ability and physical characteristics of the isolates.Methods: A total of 74 E. coli isolates were tested for antimicrobial susceptibility with the disc diffusion assay. Based on the SXT-susceptibility test, the E. coli isolates were divided into SSEC(N = 30) and SREC(N = 44) groups. All E. coli isolates were examined for motile ability by using a motility test medium, and for checking bioi lm formation a scanning electron microscope was used. Bacterial colony size was measured with a vernier caliper and bacterial cell length was measured under a light microscope. The bacterial growth rate was studied by plotting the cell growth(absorbance) versus the incubation time. Results: The frequencies of non-motility and biofilm formation in the SREC group were signii cantly higher than that in the SSEC group(P < 0.01). The SREC bacterial cell length was shorter than that in the SSEC group [(1.35 ± 0.05) vs.(1.53 ± 0.05) μm, P < 0.05)], whereas the bacterial colony size and mid-log phase of the growth curve were not signii cantly dif erent. Conclusions: The present study indicated that bioi lm formation and phenotypic change of uropathogenic E. coli can be attributed to the mechanism of E. coli SXT resistance.
基金This research was supported by the Natural Science Foundation of Shandong Province(ZR2019MEE038)the Fundamental Research Funds for the Central Universities(19CX02038A).
文摘In this study,nitrogen removal performance of the denitrifying ammonium oxidation(DAO)process was investigated when treating sulfamethoxazole(SMX)-laden secondary wastewater effluent.The influent SMX concentration showed negligible effect on efficiencies for removal of nitrate and COD.However,the ammonium ions removal rate was moderately reduced,when the influent SMX concentration in wastewater reached 6 mg/L.Total nitrogen removal efficiency remained as high as 76.77%towards the day 158 at the end of experiment.Candidatus_Brocadia and Candidatus_Kuenenia were the functional anammox strains.The unclassified_f__Rhodobacteraceae sp.was predominant heterotrophic denitrifying strain in the studied reactor.The concentrations of soluble extracellular polymeric substances in sludge obviously increased from 16.76 mg/g VSS to 32.31 mg/g VSS,which might protect the nitrogen removal strains from high-concentration SMX.This result provides a theoretical and technical foundation for the application of denitrifying ammonium oxidation process in treating sulfamethoxazole-laden secondary wastewater effluent.
文摘Our previous study suggested that the production of superantigens and heat-shock protein 60 by small intestinal bacteria might play a role in Kawasaki disease (KD). We demonstrated that they were all resistant to commonly used antibiotics, except for sulamethoxazole trimethoprim (SMX-TMP). We used SMX-TMP for 7 cases of KD that were unresponsive to intravenous immunoglobulin (IVIG) and studied the antipyretic potency of this treatment. In 6 out of the 7 cases, we demonstrated that antipyretic potency was observed without side effects within 2 days of the initial administration. Antimicrobial therapy using SMX-TMP might represent a novel strategy for cases of KD that are unresponsive to IVIG.
文摘Nanoporous Carbon (NPC) with high surface area of 1379 M2/G and high proportion of micropore and mesopore volume of 2.90 Cm3/G was prepared by carbonization of metal?organic frameworks ZIF-8. The adsorption of NPC towards the representative sulfonamide antibiotics sulfamethoxazole (SMX) from aqueous solutions was explored, in comparison with powder active carbon (AC). The adsorption kinetics and isotherms showed that the maximum adsorption capacity (Qm) of NPC toward SMX was 757 Mg/G, around 2 times than that of AC adsorption. The high adsorption affinity of NPC was related to the high surface area and special Mic/Mesopore structure. The pore-filling mechanism as well as electrostatic interaction had important influence on the high adsorption of NPC. The results implied that nanoporous carbon derived from mofs could remove the contaminants from aqueous solutions effectively, and would be a promising adsorbent for the removal of contaminants in the future.
文摘<strong>Background:</strong> Sulfamethoxazole/Trimethoprim is a commonly used drug in a variety of clinically indicated scenarios, but it is not without side effect. Case-reports have stated that adverse reactions secondary to Sulfamethoxazole/Trimethoprim can present very early in the course of treatment, especially in patients who have a higher predisposition. Thus, the burden is placed on the clinician to be wary of these side effects and be able to recognize them in the correct clinic scenario. Objective: To discuss the risk of developing cholestatic hepatic dysfunction secondary to treatment with sulfamethoxazole/trimethoprim. <strong>Methods:</strong> We present the history, physical findings, laboratory investigations, and clinical course of a 47-year-old African-American female who developed cholestatic hepatic dysfunction after treatment with sulfamethoxazole/trimethoprim for pyelonephritis. <strong>Results:</strong> Drug-induced liver injury is a rare complication of sulfamethoxazole/trimethoprim therapy and only 20% of cases are secondary to cholestatic hepatic dysfunction. Our patient, who had been on sulfamethoxazole/trimethoprim for 7 days for pyelonephritis, presented to our hospital with a clinical picture consistent with hepatic injury;her laboratory investigations were noteworthy for an elevated white blood cell count, platelet count, and elevated transaminases, along with alkaline phosphatase levels greater than 2 times the upper limit of normal. Promptly following the discontinuation of sulfamethoxazole/trimethoprim, our patient improved clinically and her liver enzymes down-trended during the course of her hospital stay. She returned to normal at her 4 month follow up, thus confirming the diagnosis of cholestatic hepatic dysfunction secondary to sulfamethoxazole/trimethoprim. <strong>Conclusion:</strong> Cholestatic hepatic dysfunction is a form of drug-induced liver injury and a rare complication of sulfamethoxazole/trimethoprim treatment. The majority of cases resolve following discontinuation of the offending medication. However, a small percentage of patients may progress to liver failure and ultimately require liver transplantation. Clinicians should be aware of these risks to avoid delaying the discontinuation of sulfamethoxazole/trimethoprim.
文摘Sulfamethoxazole-trimethoprim (TMP-SMX)-induced rhabdomyolysis is a rare complication of a commonly used antibiotic. This is a case report of a 43-year old immunocompetent African American woman with a history of depression and chronic alcohol consumption who presented to the emergency department (ED) with worsening bilateral leg pain. Before presentation, the patient was prescribed a twice daily dose of TMP-SMX for a urinary tract infection. The patient reported the development of intensifying leg pain after taking five doses of TMP-SMX. On presentation to the ED she was hemodynamically stable, afebrile, and leg pain intensity 10 out of 10. The patient admitted to daily alcohol consumption and taking vortioxetine 10 mg per day for treatment of depression. Initial labs drawn in the ED showed an elevated creatine kinase (CK) of 26,231 U/L and a normal serum creatinine (SCr) of 1 mg/dL. Through patient history and laboratory tests, common causes of rhabdomyolysis were ruled out. Treatment was initiated with IV fluids plus thiamine and folic acid supplementation, TMP-SMX was discontinued, and vortioxetine 10 mg per day was continued until hospital day five. The patient began to show improvement in lower extremity pain and tenderness and was discharged on hospital day eight with minimal residual leg pain and a CK of 2809 U/L. This case report presents only the third incidence of an immunocompetent patient developing TMP-SMX-induced rhabdomyolysis. This case highlights an opportunity for a pharmacist’s intervention and the need for future research to determine risk factors of TMP-SMX-induced rhabdomyolysis in immunocompetent patients.
文摘Objectives: To determine the mutant prevention concentration (MPC) of sulfamethoxazole-trimethoprim (SXT) alone and in combination with levofloxacin (LVX) against Stenotrophomonas maltophilia (S. maltophilia) and to determine if the combination may decrease the emergence of resistant mutants. Methods: The MPC with 20 S. maltophilia strains which were both susceptible to SXT and LVX were determined by inhibiting visible growth among 1010 CFU on four agar plates after 72 hours incubation at 37°C. Results: All except two strains (18/20) showed a mutant prevention concentration ≥ 152/8 μg/mL for SXT and the range of the mutant prevention concentration for the SXT in combination with LVX is 9.5/0.5~608/32 μg/mL, which demonstrates at least 2 fold reduction except one strain. There was a significant difference (P < 0.01) between SXT alone and in combination with LVX on the mutant prevention concentration and mutant prevention concentration/minimum inhibitory concentration values. Conclusions: The MPC/MIC values were narrowed for SXT by combining with LVX against the S maltophilia. The combination may decrease the enrichment of mutant bacterial populations. Much study is needed to verify whether the using of drug combinations may restrict or even block the selection of S. maltophilia mutants.
文摘Trimethoprim-Sulfamethoxazole (TMP-SMZ) is associated with severe hepatic toxicity or liver failure. We present a case of severe hepatic toxicity for whom TMP-SMZ was prescribed as part of treatment for mixed connective tissue disease (MCTD). TMP-SMZ was used to prevent complications from steroid therapy, but fever and hepatic toxicity developed with repeated TMP-SMZ medication. While the drug lymphocyte stimulation test (DLST) for TMP-SMZ showed negative, the genotype for N-acetyltransferase 2 (NAT2) showed type *6/*7, which is the slow acetylating type for NAT2 activity. This finding for NAT2 genotype and the patient’s clinical history lead us to speculate that her fever and hepatic toxicity were caused by TMP-SMZ.
基金Supported by the National Natural Science Foundation of China(No.31101298)the Special Scientifi c Research Funds for Central Non-Profi t Institutes,Chinese Academy of Fishery Sciences(No.2014A09XK02)partially by the Independent Innovation Foundation of Shandong Province(No.2013CXC80202)
文摘The pharmacokinetic profi les and sulfamethoxazole(SMX) acetylation process in turbot reared at 18°C were investigated. Either SMX(parent drug) or its acetylized metabolite, N4-acetylsulfamethoxazole(Ac SMX), was administered intravascularly to turbot at a dosage of 50 mg/kg BW. Serum concentrations of the parent drug and its metabolite were both measured by HPLC, and the changes in concentration over time were analyzed in two- and non-compartment models because SMX treatment produced multiple peaks. The results demonstrated that the elimination half-life of the parent drugs, SMX and Ac SMX, were 159.2 and 5.9 h, respectively. The apparent volume of distribution was 0.2 and 0.8 L/kg, and the clearance was 0.038 and 0.222 L/(h·kg), for SMX and Ac SMX, respectively. SMX acetylation in turbot was 2.8%, and the deacetylation of Ac SMX was 0.2%. These fi ndings may be useful in optimizing SMX dosage regimens in turbot aquaculture.
文摘This study was designed to examine the interaction of sulfamethoxazole(SMZ) with human serum albumin(HSA).Spectroscopic analysis of the emission quenching at different temperatures revealed that the quenching mechanism of human serum albumin by SMZ was static mechanism.The binding constant values for the SMZ-HSA system were obtained to be 22,500 L/mol at 288 K,15,600 L/mol at 298 K,and 8500 L/mol at 308 K.The distance r between donor and acceptor was evaluated according to the theory of Foster energy transfer.The results of spectroscopic analysis and molecular modeling techniques showed that the conformation of human serum albumin had been changed in the presence of SMZ.The thermodynamic parameters,namely enthalpy change(△H^0)-36.0 kJ/mol,entropy change(△S^0)-41.3 J/mol K and free energy change(△G^0)-23.7 kJ/mol,were calculated by using van't Hoff equation.The effect of common ions on the binding of SMZ to HSA was tested.
基金The authors greatly acknowledge the financial support from the National Natural Science Foundation of China(No.60027001 and 60302003)the National High Technology Research and Development program of China(No.20060100Z3044).
文摘A homemade array surface plasmon resonance (SPR)-based imaging biosensor was used to develop sensitive and fast immunoassays to determine sulfamethoxazole (SMOZ) and sulfamethazine (SMT) in buffer. Two conjugations of sulfonamide-bovine serum albumin (BSA) were separately immobilized on two different rows of the array chip with one row as reference. The immobilization was carried out in the instrument to monitor the quantity of the conjugations immobilized. The antibody mixed with the sulfonamide in the buffer was injected over the surface of the chip to get a relative response which was inversely proportional to the concentration of the sulfonamide in the PBS buffer. Two calibration curves were constructed and the limit of detection for sufamethoxazole in buffer was 3.5 ng/mL and for sulfamethazine 0.6 ng/mL. The stability and specificity of the antibody were also studied. The monoclonal antibody did not bind with BSA.
基金supported by National Natural Science Foundation of China(No.20405013)
文摘A new indirect inhibitive immunoassay using surface plasmon resonance(SPR) coupled with molecularly imprinted polymer(MIP) was developed.A sulfamethoxazole(SMX) MIP coating capillary was produced and used as an in-tube solid phase extraction(SPE) device.The MIP coating formed a nanometer film on the inner wall of the capillary.The anti-SMX mono-antibody was inhibited by SMX extracted by the MIP coating in a dose-dependent manner.The calibration curve was generated by linear fit over the range of 0.04-10.00 ng/mL.The limit of detection was 0.01 ng/mL.This method has high sensitivity and can be performed automatically.
基金financially supported by the Natural Science Foundation of China(Nos.41702040,41771272)Natural Science Foundation of Hunan Province(No.2021JJ40256)the Double First-Class Construction Project of Hunan Agricultural University(No.SYL2019043)
文摘It has been documented that organic contaminants can be degraded by hydroxyl radicals(•OH)produced by the activation of H2O2 by Fe(II)-bearing clay.However,the interfacial electron transfer reactions between structural Fe(Ⅱ)and H_(2)O_(2) for•OH generation and its effects on contaminant remediation are unclear.In this study,we first investigated the relation between•OH generation sites and sulfamethoxazole(SMX)degradation by activating H2O2 using nontronite with different reduction extents.SMX(5.2–16.9μmol/L)degradation first increased and then decreased with an increase in the reduction extent of nontronite from 22% to 62%,while the•OH production increased continually.Passivization treatment of edge sites and structural variation results revealed that interfacial electron transfer reactions between Fe(Ⅱ)and H2O2 occur at both the edge and basal plane.The enhancement on basal plane interfacial electron transfer reactions in a high reduction extent rNAu-2 leads to the enhancement on utilization efficiencies of structural Fe(Ⅱ)and H_(2)O_(2) for•OH generation.However,the•OH produced at the basal planes is less efficient in oxidizing SMX than that of at edge sites.Oxidation of SMX could be sustainable in the H_(2)O_(2)/rNAu-2 system through chemically reduction.The results of this study show the importance role of•OH generation sites on antibiotic degradation and provide guidance and potential strategies for antibiotic degradation by Fe(Ⅱ)-bearing clay minerals in H2O2-based treatments.
基金the funding supports from the National Natural Science Foundation of China (Nos. 22076052 and 21976063)China Postdoctoral Science Foundation (No. 2018M642850)。
文摘A novel hierarchical bowl-like FeCuS@Cu_(2)S@Fe^(0)nanohybrid catalyst(B-FeCuS@Cu_(2)S@Fe^(0))was synthesized for removing sulfamethoxazole(SMX) through catalytic activation of peroxymonosulfate(PMS). It was found that this catalyst exhibited excellently high catalytic activity. Under optimized reaction conditions, all the added SMX(12 mg/L) could be completely degraded within 5 min. The SMX degradation followed pseudo first order kinetics with a rate constant k of 0.89 min^(-1), being 1.38, 4.51, 8.99 and 35.6 times greater than that of other catalysts including Fe^(0)(0.644 min^(-1)in the very initial stage), bowl-like iron-doped CuS(B-FeCuS, 0.197 min^(-1)), bowl-like CuS(B-CuS, 0.099 min^(-1)) and Cu_(2)O(0.025 min^(-1)), respectively. During the degradation, several reactive oxygen species(·OH, SO_(4)·-and1O_(2)) were generated with ·OH as the main one as confirmed by electron paramagnetic resonance analysis. The SMX degradation in the present system included both radical and non-radical mediated processes. A possible mechanistic insight of the PMS activation by bowl Fe^(0)decorated CuS@Cu_(2)S-based catalyst was proposed according to X-ray photoelectron spectroscopic(XPS) analysis, and the degradation pathway of SMX was speculated by monitoring the degradation intermediates with liquid chromatography coupled with mass spectrometry(LC-MS).
基金supported by the National Natural Science Foundation of China (Nos. 41671468, 41967043)the Qing Lan Project of Jiangsu Province, Science and Technology Service Network Initiative (No. KFJ-STS-QYZX-051)+1 种基金the Educational and Teaching Reforms Project of Ministry of Education (No. GPSJZW2020-31)the Fundamental Research Funds for the Central Universities。
文摘To understand the long-term performance of bioretention systems under sulfamethoxazole (SMX) stress, an unplanted bioretention system (BRS) and two modified BRSs with coconut-shell activated carbon (CAC) and CAC/zero-valent-iron (Fe^(0)) granules (CAC-BRS and Fe/CAC-BRS) were established. Both CAC-BRS and Fe/CAC-BRS significantly outperformed BRS in removing total nitrogen (TN)(CAC-BRS:82.48%;Fe/CAC-BRS:78.08%;BRS:47.51%), total phosphorous (TP)(CAC-BRS:79.36%;Fe/CAC-BRS:98.26%;BRS:41.99%),and SMX (CAC-BRS:99.74%, Fe/CAC-BRS:99.80%;BRS:23.05%) under the long-term SMX exposure (0.8 mg/L, 205 days). High-throughput sequencing revealed that the microbial community structures of the three BRSs shifted greatly in upper zones after SMX exposure.Key functional genera, dominantly Nitrospira, Rhodoplanes, Desulfomicrobium, Geobacter,were identified by combining the functional prediction by the FAPROTAX database with the dominant genera. The higher abundance of nitrogen functional genes (nirK, nirS and nos Z) in CAC-BRS and Fe/CAC-BRS might explain the more efficient TN removal in these two systems. Furthermore, the relative abundance of antibiotic-resistant genes (ARGs)sul I and sulII increased in all BRSs along with SMX exposure, suggesting the selection of bacteria containing sul genes. Substrates tended to become reservoirs of sul genes. Also,co-occurrence network analysis revealed distinct potential host genera of ARGs between upper and lower zones. Notably, Fe/CAC-BRS succeeded to reduce the effluent sul genes by1-2 orders of magnitude, followed by CAC-BRS after 205-day exposure. This study demon-strated that substrate modification was crucial to maintain highly efficient nutrients and SMX removals, and ultimately extend the service life of BRSs in treating SMX wastewater.
基金supported by the National Key R&D Program of China(No.2018YFE0106400)。
文摘The impact of antibiotics on the environmental protection and sludge treatment fields has been widely studied.The recovery of hydrogen from waste activated sludge(WAS)has become an issue of great interest.Nevertheless,few studies have focused on the impact of antibiotics present in WAS on hydrogen production during dark anaerobic fermentation.To explore the mechanisms,sulfamethoxazole(SMX)was chosen as a representative antibiotic to evaluate how SMX influenced hydrogen production during dark anaerobic fermentation of WAS.The results demonstrated SMX promoted hydrogen production.With increasing additions of SMX from 0 to 500 mg/kg TSS,the cumulative hydrogen production elevated from 8.07±0.37 to 11.89±0.19 mL/g VSS.A modified Gompertz model further verified that both the maximum potential of hydrogen production(Pm)and the maximum rate of hydrogen production(R_(m))were promoted.SMX did not affected sludge solubilization,but promoted hydrolysis and acidification processes to produce more hydrogen.Moreover,the methanogenesis process was inhibited so that hydrogen consumption was reduced.Microbial community analysis further demonstrated that the introduction of SMX improved the abundance of hydrolysis bacteria and hydrogen-volatile fatty acids(VFAs)producers.SMX synergistically influenced hydrolysis,acidification and acetogenesis to facilitate the hydrogen production.
