RESUMEN
Little information is known about the relationships of in-situ generated BioMnOx and sulfamethoxazole (SMX) degradation. In this study, a novel efficient bioremediation technology was presented for simultaneous remove the nitrogen-N, SMX, and Mn(II) from water. Mn(II) can be completely oxidized with a oxidized rate of 0.071 mg/(L·h), the SMX and nitrogen-N removal ratios were 97.43% and 85.61%, respectively. The Ratkowsky kinetic models were established for described the SMX degradation influence by temperature. Furthermore, the microbial degradation, Mn(III) trapping, and intermediates identified experiments were used to explore the mechanisms of SMX and nitrogen-N removal. These results indicated that microbial activity play a decisive role in SMX and nitrogen-N removal, and the catalytic character of sediment could enhanced the SMX degradation. Furthermore, proposed the possible SMX degradation pathway based on the intermediates and microbial metabolism theory, the environmental toxicity of SMX and each intermediates were calculated via ECOSAR program.
Asunto(s)
Achromobacter , Contaminantes Químicos del Agua , Manganeso , Óxidos , Sulfametoxazol , Contaminantes Químicos del Agua/análisisRESUMEN
The effect of the novel composite material LiNbO3@Fe3O4 on the nitrate removal, and Mn2+ oxidation efficiency by autotrophic denitrification strain Achromobacter sp. A14 was investigated in this study. The optimum conditions were tested by using five levels of initial Mn2+ concentrations (40, 60, 80, 100 and 120â mg/L), initial pH (5.0, 6.0, 7.0, 8.0 and 9.0) and temperature (20, 25, 30, 35 and 40°C). A maximal nitrate removal ratio of nearly 100% and a maximal Mn2+ oxidation ratio of 71.59% were simultaneously achieved at pH 7.0, 80â mg/L Mn2+ and 30°C by bacteria A14 with 300â mg/L LiNbO3@Fe3O4 as catalytic material. Biomaterial cycle testing indicated that the denitrification efficiency of bacteria A14 with LiNbO3@Fe3O4 remained steady after 10 batches.
Asunto(s)
Achromobacter , Desnitrificación , Achromobacter/genética , Procesos Autotróficos , Bacterias , NitratosRESUMEN
This study investigated whether bioaugmentation improves sulfamethoxazole (SMX) degradation and nitrogen removal in the Moving Bed Biofilm Reactor (MBBR) system. The effects of the C/N ratio on SMX degradation and nitrogen removal were also evaluated. Using MBBR system operation experiments, the bioaugmented reactor was found to perform more effectively than the non-bioaugmentation reactor, with the highest SMX, nitrate-N, and ammonia-N removal efficiencies of 80.49, 94.70, and 96.09%, respectively. The changes in the sulfonamide resistance genes and bacterial communities were detected at various operating conditions. The results indicate that the diversity of the bacterial communities and the abundance of resistance genes were markedly influenced by bioaugmentation and the C/N ratio, with Achromobacter among the dominant genera in the MBBR system. The bio-toxicity of samples, calculated as the inhibition percentage (IP) toward Escherichia coli, was found to decrease to non-toxic ranges after treatment.
Asunto(s)
Acuicultura , Sulfametoxazol/metabolismo , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/metabolismo , Achromobacter/metabolismo , Amoníaco , Biopelículas , Reactores Biológicos/microbiología , Nitratos , Nitrógeno , Aguas Residuales/microbiologíaRESUMEN
Little information is available regarding the kinetics, products, and pathways of simultaneous SMX degradation and Cd(II) immobilization from wastewater. In this study, a novel bacterium (Achromobacter sp. L3) with SMX degradation and Cd(II) immobilization capabilities was isolated. The boundary conditions of SMX degradation were as follows: initial pH 6-8, temperature 25-30 °C, and SMX concentration 10-40 mg/L-1. The boundary conditions of Cd(II) immobilization were as follows: initial pH 7-9, temperature 25-35 °C, and SMX concentration 10-30 mg/L-1. The maximum SMX degradation and Cd(II) removal were 91.98% and 100%, respectively. The SMX degradation and Cd(II) immobilization data fitted well with the pseudo-first-order kinetic model, indicating that the two pollutants conform to the same degradation rule. Moreover, the microbial degradation, sediment adsorption, and intermediates identified in the experiments were used to explore the mechanisms of SMX and Cd(II) removal. These results indicate that microbial removal and sediment adsorption play equally important roles in Cd(II) immobilization; however, microbial degradation plays a decisive role in SMX degradation. Furthermore, the relationship between aerobic denitrification, SMX degradation, and Cd(II) immobilization was proposed. These results may provide valuable insights for treatment of wastewater polluted by antibiotics and heavy metals.
Asunto(s)
Achromobacter , Metales Pesados , Contaminantes Químicos del Agua , Cadmio , Sulfametoxazol , Aguas Residuales/análisis , Contaminantes Químicos del Agua/análisisRESUMEN
The pharmaceutical industry produces large volumes of low C/N ratio wastewater that is difficult to treat. In this study, we isolated Achromobacter sp. JL9 with high efficiency for sulfamethoxazole degradation and nitrogen conversion in low C/N ratio pharmaceutical wastewater. The SMX biodegradation and nitrogen removal ratio were 92.4% (nitrate-N), 86.7% (ammonia-N), 89.4% (total nitrogen), and 90.4% (SMX). The reaction kinetics and reaction rate constant were C/N ratio-, SMX concentration-, and dissolved oxygen concentration-dependent, and the highest reaction rate constant for SMX biodegradation was 0.0384 min-1. Gaseous compounds analysis and Nap gene amplification analysis by gas chromatography (GC) and polymerase chain reaction (PCR), respectively, showed N2 as an end product during nitrogen conversion. Moreover, toxicity assays were conducted by the inhibition percentage (PI) and agar well diffusion methods. The toxicity of the medium gradually decreased, falling within the nontoxic range after 96 h. The present study showed that biological technologies could be an effective, economical, and environmentally friendly remediation against pharmaceutical pollutants.
Asunto(s)
Achromobacter/metabolismo , Biodegradación Ambiental , Nitrógeno/metabolismo , Sulfametoxazol/metabolismo , Contaminantes Químicos del Agua/metabolismo , Aguas Residuales/química , Aguas Residuales/microbiologíaRESUMEN
This study investigated sulfamethoxazole (SMX) biodegradation and nitrogen conversion by Achromobacter sp. JL9 using different carbon and nitrogen sources. Results showed that SMX and sodium acetate could be co-metabolized as carbon sources for bacterial growth and nitrogen conversion with highest removal efficiencies of 82.44%, 80.2%, and 79.45% for NH4+-N, NO3--N, and SMX, respectively. Strain JL9 was able to utilize SMX as its sole nitrogen source for growth, with an SMX biodegradation efficiency of 63.10%. In addition, carbon and nitrogen balance analyses showed that approximately 35.31% and 63.22% of carbon and nitrogen, respectively, were lost as gaseous products. Finally, medium toxicity gradually decreased during the carbon and nitrogen dependence experiments. This study, thus, suggests that carbon and nitrogen play vital roles in SMX biodegradation and biotoxicity reduction.
Asunto(s)
Achromobacter , Sulfametoxazol , Biodegradación Ambiental , Carbono , NitrógenoRESUMEN
An immobilized biofilm reactor (IBR) was established to treat nitrate using different electron donors. A novel material, Fe3O4@Cu/PVA, was synthesized as an adsorbent and bacterial immobilized carrier in the reactor. The optimum condition of nitrate removal were pH 7.0, hydraulic retention time (HRT) of 10â¯h under autotrophic and mixotrophic conditions. Strain H-117 in the mixotrophic reactor had better adaptability to changes in the initial pH. The metabolism in the mixotrophic reactor was more vigorous than that in autotrophic reactor. The microbial communities and structures were evaluated to determine the nitrate removal mechanisms in this system. Microbial analyses demonstrated that different electron donor could influence the bacterial abundance and species in the IBR system. Proteobacteria was the most dominant phylum in all IBRs and accounted for more than 50% of the total phyla. Pseudomonas and Rhizobium were the dominant contributor to the effective removal of nitrate in the IBRs.
Asunto(s)
Desnitrificación , Microbiota , Procesos Autotróficos , Biopelículas , Reactores Biológicos , NitratosRESUMEN
In this study, zero-valent iron (ZVI), nanoscale zero-valent iron (nZVI), Fe(II), and Mn(II) were investigated for their effects on mixotrophic denitrification coupled with cadmium (Cd(II)) adsorption process by Acinetobacter sp. SZ28. The removal rates of nitrate were 0.228 mg L-1 h-1 (ZVI), 0.133 mg L-1 h-1 (nZVI), 0.309 mg L-1 h-1 (Fe(II)) and 0.234 mg L-1 h-1 (Mn(II)), respectively. The Cd(II) removal efficiencies were 97.23% (ZVI), 95.79% (nZVI), 80.63% (Fe(II)), and 84.58% (Mn(II)), respectively. Meteorological chromatography analysis indicated that the characteristics of gas composition were different under different electron donor conditions. Moreover, characterization of bacterial metabolites produced by strain SZ28 under different conditions was analyzed. Sequence amplification identified the presence of the nitrate reductase gene (napA) and Mn(II)-oxide gene (cumA) in strain SZ28. The results of XRD and SEM indicated that ZVI, nZVI, Fe(II), and Mn(II) were oxidized into corresponding oxides. XPS spectra indicated that the Cd(II) was adsorbed onto biogenic precipitation.
Asunto(s)
Acinetobacter/metabolismo , Cadmio/metabolismo , Nitratos/metabolismo , Contaminantes Químicos del Agua/metabolismo , Purificación del Agua/métodos , Acinetobacter/genética , Adsorción , Proteínas Bacterianas/genética , Cadmio/aislamiento & purificación , Desnitrificación , Electrones , Hierro/química , Hierro/metabolismo , Manganeso/química , Manganeso/metabolismo , Microscopía Electrónica de Rastreo , Nitrato-Reductasa/genética , Nitratos/aislamiento & purificación , Contaminantes Químicos del Agua/aislamiento & purificación , Difracción de Rayos XRESUMEN
The aim of this study was to identify algicidal bacteria J25 against the Microcystis aeruginosa (90.14%), Chlorella (78.75%), Scenedesmus (not inhibited), and Oscillatoria (90.12%). Meanwhile, we evaluate the SOD activity and efficiency of denitrification characteristics with Acinetobacter sp. J25. A novel hybrid bioreactor combined biological floating bed with bio-contact oxidation (BFBO) was designed for treating the landscape water, and the average removal efficiencies of nitrate-N, ammonia-N, nitrite-N, TN, TP, TOC, and algal cells were 91.14, 50, 87.86, 88.83, 33.07, 53.95, and 53.43%, respectively. A 454-pyrosequencing technology was employed to investigate the microbial communities of the BFBO reactor samples. The results showed that Acinetobacter sp. J25 was the dominant contributor for effective removal of N, algal cells, and TOC in the BFBO reactor. And the relative abundance of Acinetobacter showed increase trend with the delay of reaction time. Graphical abstract Biological floating bed and bio-contact oxidation (BFBO) as a novel hybrid bioreactor designed for simultaneous removal Microcystis aeruginosa, TOC, nitrogen, and phosphorus. And high-throughput sequencing data demonstrated that Acinetobacter sp. J25 was the dominate species in the reactor and played key roles in the removal of N, TOC, and M. aeruginosa. Proposed reaction mechanism of the BFBO.
Asunto(s)
Microcystis/fisiología , Nitrógeno/metabolismo , Fósforo/metabolismo , Purificación del Agua/métodos , Acinetobacter/fisiología , Amoníaco/metabolismo , Productos Biológicos , Reactores Biológicos , Carbono/metabolismo , Chlorella/fisiología , Desnitrificación , Nitratos/metabolismo , Nitritos/metabolismo , Oscillatoria/fisiología , Oxidación-Reducción , Scenedesmus/microbiología , Scenedesmus/fisiología , Microbiología del Agua , Purificación del Agua/instrumentaciónRESUMEN
This study investigates the impacts of influent ammonium concentrations on the microbial community in immobilized heterotrophic ammonium removal system. Klebsiella sp. FC61, the immobilized species, has the ability to perform simultaneous ammonium removal and Fe3+ reduction. It was found that average ammonium removal rate decreased from 0.308 to 0.157 mg/L/h, as the influent NH4+-N was reduced from 20 to 10 mg/L. Meanwhile, at a total Fe3+ concentration of 20 mg/L, the average Fe3+ reduction removal efficiency and rate decreased from 44.61% and 0.18 mg/L/h, to 27.10% and 0.11 mg/L/h, respectively. High-throughput sequencing was used to observe microbial communities in bioreactor Samples B1, B2, and B3, after exposure to different influent NH4+-N conditions. Results show that higher influent NH4+-N concentrations increased microbial richness and diversity and that Klebsiella sp. FC61 play a functional role in the simultaneous removal of NH4+-N and Fe3+ reduction in bioreactor systems.
Asunto(s)
Amoníaco/metabolismo , Reactores Biológicos/microbiología , Compuestos Férricos/metabolismo , Klebsiella/crecimiento & desarrollo , Consorcios Microbianos/fisiología , Oxidación-ReducciónRESUMEN
In this study, immobilization technique was employed to improve simultaneous algicidal and denitrification of immobilized Acinetobacter sp. J25 with magnetic Fe3O4 in eutrophic landscape water. After 7 days of operation, the maximum superoxide dismutase (SOD) activity (54.43 U mg-1), nitrate removal efficiency (100% (0.2127 mg L-1 h-1)), and chlorophyll-a removal efficiency (89.71%) were obtained from the immobilized J25 with magnetic Fe3O4. The results suggest that immobilized J25 with magnetic Fe3O4 had better nitrogen removal efficiency and algicidal activity in eutrophic landscape water. High-throughput sequencing data profiled the strain J25 that was immobilized with magnetic Fe3O4 which changed the composition of the microbial community. The results indicated a novel concept of enhancing the algicidal and denitrification property of immobilized bacteria with magnetic Fe3O4 in eutrophic landscape water.
Asunto(s)
Acinetobacter , Desnitrificación , Nanopartículas del Metal , Microcystis , NitratosRESUMEN
Coronary heart disease (CHD) is a major disease greatly harmful to the health of human beings. The incidence and case fatality rate of female CHD show an increasing tendency due to lack of enough attention. Through analyzing the epidemiology, risk factors, and clinical characteristics of female CHD, we emphasized that it is necessary to pay enough attention to the particularity of female CHD, and put forward the thinking way of diagnosis and treatment of integrative medicine as "integrating Chinese medicine and Western medicine by mutual complement of advantages; combining syndrome typing and disease identification by grasping laws; treating physically and mentally by a wholism concept; spreading health education, preventing and treating comprehensively".
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Enfermedad Coronaria/diagnóstico , Enfermedad Coronaria/terapia , Medicina Integrativa , Medicina Tradicional China/métodos , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Humanos , FitoterapiaRESUMEN
OBJECTIVE: To investigate effects of serum HDL(1) on the formation of foam cells from human peripheral blood monocyte-derived macrophages. METHODS: Sectie density polyacrylamide gel electrophoresis (sd-PAGE) was applied for isolation and preparation of HDL(1) simultaneously. Monocytes were isolated from human peripheral blood by Ficoll-Hypaque density gradient centrifugation and plastic adsorptive process. The isolated monocytes were stimulated by phorbol 12-myristate 13-acetate (PMA) at a concentration of 50 nmol/L for 48 h and transferred to macrophages. The monocyte-derived macrophages were then coincubated with 80 mg/L ox-LDL and HDL(1) (0, 0.1, 1.0 and 10.0 mg/L) for 6, 12 and 24 h, respectively. The formation of foam cells was identified by transmission electron microscope (TEM), total cholesterol (TC), free cholesterol (FC) and protein (Pro) in cultured cells were quantitatively analyzed by high performance chromatography (HPLC) and modified lowry protein assay, respectively. RESULTS: HDL(1) isolated from human serum by sd-PAGE could significantly decrease TC/Pro ratio in foam cells in a concentration-dependent (0 mg/L: 36.9 +/- 1.1, 10.0 mg/L: 6.2 +/- 0.4, P < 0.01) and time-dependent (10.0 mg/L HDL(1) 6 h: 16.9 +/- 0.9, 24 h: 6.4 +/- 0.6, P < 0.01) manner. CONCLUSION: HDL(1) is capable of inhibiting and attenuating the formation of foam cells by decreasing cellular TC, therefore, might play an important role in attenuating atherosclerosis.
Asunto(s)
Células Espumosas/citología , Lipoproteínas HDL/sangre , Monocitos/citología , Aterosclerosis , Células Cultivadas , LDL-Colesterol/metabolismo , Células Espumosas/metabolismo , Humanos , Lipoproteínas LDL , Monocitos/metabolismoRESUMEN
OBJECTIVE: To explore the relationship of Pi-deficiency syndrome in TCM with the change of serum high density lipoprotein (HDL) in blood lipid metabolic disorder. METHODS: Sixty-eight patients with confirmed coronary heart disease (CHD) were selected for TCM syndrome typing into Pi-deficiency (PD) group and non-Pi-deficiency (NPD) group. Routine blood lipids and serum lipoprotein electrophoretogram (SLPG) were determined in all patients to analyze the total content of HDL and its relative contents of sub-components HDL(1-5), as well as their relation with PD syndrome. Besides, a healthy control group (62 cases) was set up. RESULTS: The level of serum HDL-C was lowered, SLPG abnormality rate increased in the patients with CHD, with total HDL and the relative contents of subcomponent HDL(1) and HDL(3) significantly lower than those in the healthy control group (P<0.01). The total HDL, HDL(1) and HDL(3) in the PD group were also lower than those in the NPD group (P<0.05, P<0.01). CONCLUSION: Serum HDL and its sub-components showed a definite relation with TCM PD syndrome type, therefore, further exploring the granular specificity of HDL and its sub-components as well as their influence on reverse cholesterol transport (RCT) may hopefully provide clues for developing RCT regulatory Chinese new drugs and for CHD prevention and treatment.