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1.
Chemosphere ; 352: 141515, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387659

RESUMO

Anaerobically digested swine wastewater (ASW) purification by microalgae provides a promising strategy for nutrients recovery, biomass production and CO2 capture. However, the characteristics of ASW from different cleaning processes vary greatly. At present, the cultivation of microalgae in ASW from different manure cleaning processes is rarely investigated and compared. That may bring uncertainty for microalgae growth using different ASW in large-scale application. Thus, the ASW from three cleaning processes were tested for cultivating microalgae, including manure dry collection (I), water flushing (II) and water submerging processes (III). The characteristics of ASW from three manure cleaning processes varied greatly such as nutrient and heavy metals levels. High concentration of ammonia and copper in ASW significantly inhibited microalgae growth. Fortunately, the supply of high CO2 (10%) effectively alleviated negative influences, ensuring microalgal growth at low dilution ratio. The characteristics of three ASW resulted in significant differences in microalgae growth and biomass components. The maximal biomass production in optimal diluted ASW-I, II and III reached 1.46 g L-1, 2.19 g L-1 and 2.47 g L-1, respectively. The removal of organic compounds, ammonia and phosphorus by optimal microalgae growth in diluted ASW-I, II and III was 50.6%/94.2%/64.7%, 63.7%/82.3%/57.6% and 83.2%/91.7%/59.7%, respectively. The culture in diluted ASW-I, II and III obtained the highest lipids production of 12.1 mg L-1·d-1, 16.5 mg L-1·d-1 and 19.4 mg L-1·d-1, respectively. The analysis of lipids compositions revealed that the proportion of saturated fatty acids accounted for 36.4%, 32.4% and 27.9 % in optimal diluted ASW-I, II and III, as ideal raw materials for biodiesel production.


Assuntos
Clorofíceas , Poluentes Ambientais , Microalgas , Scenedesmus , Animais , Suínos , Águas Residuárias , Biomassa , Esterco , Amônia , Dióxido de Carbono , Nitrogênio , Ácidos Graxos , Biocombustíveis , Água
2.
Huan Jing Ke Xue ; 44(5): 2635-2645, 2023 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-37177937

RESUMO

Peracetic acid (PAA), as a new oxidant, has attracted increasing attention in the treatment of refractory organic pollution in sewage. In this study, the nano core-shell Co@NC catalyst was prepared via etching and used to activate PAA to degrade sulfamethoxazole (SMX) in sewage. The results indicated that the degradation rate of SMX reached 98%, and its reaction rate constant was 0.80 min-1 under optimal conditions (catalyst dosage=0.02 g·L-1, PAA concentration=0.12 mmol·L-1, pH=7, SMX concentration=10 µmol·L-1). With the increase in PAA concentration and core-shell Co@NC dosage, the degradation efficiency of SMX increased. The study found that the core-shell Co@NC/PAA system had the best degradation effect on SMX under near-neutral conditions (pH 6.0-8.0), and both acidic and alkaline environments were not conducive to SMX degradation. HCO3- and humic acid showed significant inhibition on the degradation of SMX, whereas Cl- showed weak inhibition. In addition, through a free radical quenching experiment and electron paramagnetic resonance (EPR) detection, acetoxy radical (CH3CO2CO3·) were the main active species for the degradation of organic pollutants in the system. Transformation products (TPs) of SMX were analyzed by U-HPLC-Q-Exactive Orbitrap HRMS, and a possible degradation path of SMX was proposed. At the same time, the catalyst recycling experiment showed that the nano core-shell Co@NC catalyst had good stability and reusability.

3.
Chemosphere ; 338: 139514, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37454982

RESUMO

The microalgae culture in mixing sewage with different characteristics may significantly improve biomass production and nutrients recycling efficiency. In this study, three waste organic wastewater including molasses, alcohol and glycerol wastewater were mixed with anaerobic soybean wastewater as mediums for microalgae culture. The optimal mixture of molasses, alcohol and glycerol wastewater was at an initial carbon-nitrogen ratio of 7:1, 5:1 and 10:1, improving biomass production by 60.4%, 31.3% and 68.7%, respectively. The removal efficiencies of organics, ammonia nitrogen and phosphorus at optimal mixture were 54.8-62.4%, 79.5-99.1% and 49.3-61.5%, and the removal rates increased by 340-630%, 27.5-66.3% and 36.3-70.2% compared to the blank culture. In addition, the culture in mixed wastewater increased lipids contrast by 0.7-1.3 times, while achieving higher saturation in fatty acids. The results suggested that microalgae culture using mixed wastewater was a strategy for high biomass production and nutrients recycling efficiency.


Assuntos
Microalgas , Scenedesmus , Águas Residuárias , Glycine max , Anaerobiose , Biomassa , Glicerol , Nutrientes , Nitrogênio/análise , Fósforo , Biocombustíveis
4.
Environ Technol ; 33(10-12): 1101-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22856279

RESUMO

Degradation of carbamazepine (CBZ) using ultraviolet (UV), UV/H2O2, Fenton, UV/Fenton and photocatalytic oxidation with TiO2 (UV/TiO2) was studied in deionized water. The five different oxidation processes were compared for the removal kinetics of CBZ. The results showed that all the processes followed pseudo-first-order kinetics. The direct photolysis (UV alone) was found to be less effective than UV/H2O2 oxidation for the degradation of CBZ. An approximate 20% increase in the CBZ removal efficiency occurred with the UV/Fenton reaction as compared with the Fenton oxidation. In the UV/TiO2 system, the kinetics of CBZ degradation in the presence of different concentrations of TiO2 followed the pseudo-first order degradation, which was consistent with the Langmuir-Hinshelwood (L-H) model. On a time basis, the degradation efficiencies ofCBZ were in the following order: UV/Fenton (86.9% +/- 1.7%) > UV/TiO2 (70.4% +/- 4.2%) > Fenton (67.8% +/- 2.6%) > UV/H2O2 (40.65 +/- 5.1%) > UV (12.2% +/- 1.4%). However, the lowest cost was obtained with the Fenton process.


Assuntos
Carbamazepina/química , Poluentes Químicos da Água/química , Carbamazepina/efeitos da radiação , Peróxido de Hidrogênio , Ferro , Cinética , Oxirredução , Fármacos Fotossensibilizantes , Titânio , Raios Ultravioleta , Poluentes Químicos da Água/efeitos da radiação
5.
Chemosphere ; 308(Pt 1): 136177, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36037939

RESUMO

Anaerobic digestates were potential mediums for cultivating oleaginous microalgae, but their various components brought uncertainties for aglal growth and lipids production. In this study, three microalgae strains were tested to grow on four typical anaerobic digestates. The results showed that anaerobic food wastewater was an optimal medium for C. pyrenoidosa and S. obliquus culture (N. oleoabundanst cannot survive), achieving the highest biomass (2.15-2.32 g L-1) and lipids production (20.6-32.5 mg L-1·d-1). In contrast, three microalgae strains could grow suboptimally in anaerobic municipal (0.79-0.95 g L-1) and toilet (0.92-1.40 g L-1) wastewater, but showed poor performances in anaerobic swine wastewater. The growth of microalgae removed 40.9-63.4% of TOC, 83.7-96.3% of NH4+-N and 70.3-89.4% of TP in the three ADs. In addition, it was unfortunately found that the lipids content and saturation degree in fatty acids significantly decreased in ADs with sufficient nutrients. It suggests that some measures should be taken to balance biomass, lipids production and quality for cultivating microalgae in anaerobic digestates.


Assuntos
Poluentes Ambientais , Microalgas , Anaerobiose , Animais , Biomassa , Ácidos Graxos , Suínos , Águas Residuárias
6.
Mol Genet Genomic Med ; 8(5): e1195, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32130794

RESUMO

BACKGROUND: This study is aimed to unravel the genetic factors associated with microRNA (miRNA) expression in regulating sex-determining region Y-box 2 (SOX2)-mediated cisplatin resistance in small-cell lung cancer (SCLC). METHODS: The relevance of SOX2 expression in SCLC was analyzed in a panel of SCLC cells by quantitative real-time PCR (qPCR) and western blot (WB). We selected DMS114 cell line, in which SOX2 was amplified via lentiviral vector-mediated transfection of the SOX2 genes and tested for the half-maximal inhibitory concentration (IC50 ) by MTS assay. High-throughput sequencing and screening of differentially expressed miRNAs between SOX2-overexpressing and normal control cells were performed. Finally, miRanda software was used to verify the miRNAs bound with SOX2 and qPCR was used to identify the expression of miRNAs which were binding with SOX2. RESULTS: Cisplatin-resistant SOX2-overexpressing DMS114 cell lines were successfully developed, showing a statistically significant increase in SOX2 expression by qPCR and WB. Our results showed a typically higher IC50 value in SOX2-overexpressing cells compared with the negative controls. The high-throughput sequencing analysis revealed that 68 miRNAs were upregulated and 24 miRNAs were downregulated in the SOX2-overexpressing cells. The 24 downregulated miRNAs were further verified. Of them, a cancer-related miRNA, hsa-miR-340-5p, showed a higher binding affinity with SOX2 in network regulation mapping, which was also found to be markedly downregulated under qPCR analysis. CONCLUSION: We demonstrated that downregulated expression of hsa-miR-340-5p may affect cisplatin resistance by mediating SOX2 expression in SCLC cells, which may provide a potential target for the therapy of chemoresistant SCLCs.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/genética , MicroRNAs/genética , Fatores de Transcrição SOXB1/genética , Células A549 , Antineoplásicos/toxicidade , Cisplatino/toxicidade , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição SOXB1/metabolismo
7.
Bioresour Technol ; 247: 784-793, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30060414

RESUMO

Alcohol wastewater (AW) as carbon source for enhancing Chlorella pyrenoidosa growth and lipid accumulation in anaerobically digested starch wastewater (ADSW) was performed in outdoor cultivation. The biomass and lipid production significantly increased while adding optimal amount of AW (AW/ADSW=1:15) during exponential phase. In comparison with blank ADSW culture, the optimal AW addition increased the biomass production, lipid content and productivity by 35.29%, 102.68% and 227.91%, respectively. However, AW addition caused severe bacterial contamination and the total bacterial increased by 4.62-fold. Simultaneously, the optimal consortia of microalgae/bacteria effectively removed nutrients from the wastewater, including 405.18±36.47mgCODCr/L/day, 49.15±5.54mgN/L/day and 6.72±1.24mgP/L/day.


Assuntos
Chlorella , Lipídeos , Águas Residuárias , Biomassa , Carbono , Microalgas , Amido
8.
J Microbiol Biotechnol ; 28(12): 2019-2028, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30394042

RESUMO

Natural astaxanthin mainly derives from a microalgae producer, Haematococcus pluvialis. The induction of nitrogen starvation and high light intensity is particularly significant for boosting astaxanthin production. However, the different responses to light intensity and nitrogen starvation needed to be analyzed for biomass growth and astaxanthin accumulation. The results showed that the highest level of astaxanthin production was achieved in nitrogen starvation, and was 1.64 times higher than the control group at 11 days. With regard to the optimization of light intensity utilization, it was at 200 µmo/m²/s under nitrogen starvation that the highest astaxanthin productivity per light intensity was achieved. In addition, both high light intensity and a nitrogen source had significant effects on multiple indicators. For example, high light intensity had a greater significant effect than a nitrogen source on biomass dry weight, astaxanthin yield and astaxanthin productivity; in contrast, nitrogen starvation was more beneficial for enhancing astaxanthin content per dry weight biomass. The data indicate that high light intensity synergizes with nitrogen starvation to stimulate the biosynthesis of astaxanthin.


Assuntos
Clorofíceas/metabolismo , Clorofíceas/efeitos da radiação , Luz , Nitrogênio/metabolismo , Fotobiorreatores/microbiologia , Inanição , Biomassa , Técnicas de Cultura de Células/métodos , Clorofíceas/citologia , Clorofíceas/crescimento & desenvolvimento , Meios de Cultura/química , Relação Dose-Resposta à Radiação , Microalgas/metabolismo , Estimulação Luminosa/métodos , Doses de Radiação , Fatores de Tempo , Xantofilas/biossíntese
9.
Chemosphere ; 212: 262-271, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30145418

RESUMO

Academics researchers and "citizen scientists" from 22 countries confirmed that yellow mealworms, the larvae of Tenebrio molitor Linnaeus, can survive by eating polystyrene (PS) foam. More detailed assessments of this capability for mealworms were carried out by12 sources: five from the USA, six from China, and one from Northern Ireland. All of these mealworms digested PS foam. PS mass decreased and depolymerization was observed, with appearance of lower molecular weight residuals and functional groups indicative of oxidative transformations in extracts from the frass (insect excrement). An addition of gentamycin (30 mg g-1), a bactericidal antibiotic, inhibited depolymerization, implicating the gut microbiome in the biodegradation process. Microbial community analyses demonstrated significant taxonomic shifts for mealworms fed diets of PS plus bran and PS alone. The results indicate that mealworms from diverse locations eat and metabolize PS and support the hypothesis that this capacity is independent of the geographic origin of the mealworms, and is likely ubiquitous to members of this species.


Assuntos
Bactérias/metabolismo , Biodegradação Ambiental , Besouros/metabolismo , Microbioma Gastrointestinal/fisiologia , Larva/metabolismo , Poliestirenos/metabolismo , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , China , Besouros/crescimento & desenvolvimento , Microbioma Gastrointestinal/efeitos dos fármacos , Gentamicinas/farmacologia , Larva/crescimento & desenvolvimento
10.
Anal Sci ; 23(6): 655-9, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17575347

RESUMO

The complexation between Cu(II) and naphthochrome green (NG) is very sensitive at pH 4.09 with the formation of complex ion [Cu(NG)2(H2O)2](2-). It can thus used for the determination of Cu(II) by the light-absorption ratio variation approach (LARVA) with a good selectivity. Both the ordinary detection procedure and continuous flow analysis (CFA) were carried out, where the latter is fit for continuous and rapid analysis of samples. The limit of detection (LOD) of Cu(II) is only 1 ng/ml, which is favorable for direct monitoring of natural water. About 30 samples could be analyzed per hour by CFA. Cu(II) contents in Yangtze River, West Lake, Taihu Lake of China and seawater near Shanghai were determined with satisfactory results. The CFA-LARVA spectrophotometry was the first to be coupled and it will play an important role in the in-situ analysis of natural water quality.


Assuntos
Cobre/análise , Água Doce/análise , Água do Mar/análise , Algoritmos , Calibragem , Cátions/química , Corantes/química , Concentração de Íons de Hidrogênio , Estrutura Molecular , Fosfatos/química , Dodecilsulfato de Sódio/química , Espectrofotometria , Poluentes Químicos da Água/análise
11.
Bioresour Technol ; 200: 606-15, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26547810

RESUMO

A freshwater algae Chlorella pyrenoidosa was cultured outdoors using anaerobically digested activated sludge effluent. The effects of pH variations were evaluated. The coupled pH variations and free ammonia toxicity significantly affected the algal growth, lipids accumulation and contamination control during every season. The free ammonia toxicity at high pH levels actually inhibited the algal growth. Compared to an optimal algal growth at a pH of 5.7-6.5, biomass productivity at a high pH of 8.3-8.8 was reduced by 67.15±6.98%, 54.39±6.42% and 83.63±5.71% in the spring, fall and summer, respectively. When the pH rose above 9.1-9.6, algae were unable to grow in the wastewater. However, high pH levels reduced contamination (e.g., bacteria and microalgae grazers) and triggered lipids accumulation in algal cells. These findings suggest that pH control strategies are essential for this type of algal wastewater system, where ammonia is the dominant nitrogen source.


Assuntos
Amônia/química , Anaerobiose , Chlorella/crescimento & desenvolvimento , Esgotos , Biomassa , Ésteres , Ácidos Graxos/química , Concentração de Íons de Hidrogênio , Cinética , Lipídeos/química , Microalgas/crescimento & desenvolvimento , Nitrogênio/química , Fósforo/química , Temperatura , Águas Residuárias/microbiologia
12.
Spectrochim Acta A Mol Biomol Spectrosc ; 61(3): 447-54, 2005 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-15582812

RESUMO

The light-absorption ratio variation approach (LARVA) which produces an outstandingly increasing of analytical sensitivity was applied to the quantitative detection of ultramicro amounts of Mn(II) by light-absorption spectrometry using the competitive replacement complexation among 1,5-di(2-hydroxy-5-sulfophenyl)-3-cyanoformazan (DSPCF), Zn(II) and Mn(II) in the presence of o-phenanthroline (OPTL). Not only masks OPTL foreign metal ions but also seriously sensitize the competitive complexation. All the binary and ternary complexes were characterized by the break point approach. Results have shown that the limit of detection (3delta) of Mn(II) is only 0.7 ng ml(-1). This method has been applied to analysis of water quality with satisfactory results.


Assuntos
Manganês/análise , Água/análise , Ligação Competitiva , Formazans/química , Formazans/metabolismo , Fenantrolinas/química , Fenantrolinas/metabolismo , Zinco/análise
13.
J Environ Sci (China) ; 17(2): 271-5, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16295904

RESUMO

An aerobic bacterium strain, F-3-4, capable of effectively degrading 2, 6-ditert-butylphenol (2, 6-DTBP), was isolated and screened out from an acrylic fiber wastewater and the biofilm in the wastewater treatment facilities. This strain was identified as Alcaligenes sp. through morphological, physiological and biochemical examinations. After cultivation, the strain was enhanced by 26.3% in its degradation capacity for 2,6-DTBP. Results indicated that the strain was able to utilize 2,6-DTBP, lysine, lactamine, citrate, n-utenedioic acid and malic acid as the sole carbon and energy source, alkalinize acetamide, asparagine, L-histidine, acetate, citrate and propionate, but failed to utilize glucose, D-fructose, D-seminose, D-xylose, serine and phenylalanine as the sole carbon and energy source. The optimal growth conditions were determined to be: temperature 37 degrees C, pH 7.0, inoculum size 0.1% and shaker rotary speed 250 r/min. Under the optimal conditions, the degradation kinetics of 2,6-DTBP with an initial concentration of 100 mg/L was studied. Results indicated that 62.4% of 2,6-DTBP was removed after 11 d. The degradation kinetics could be expressed by Eckenfelder equation with a half life of 9.38 d. In addition, the initial concentration of 2,6-DTBP played an important role on the degradation ability of the strain. The maximum initial concentration of 2,6-DTBP was determined to be 200 mg/L. Above this level, the strain was overloaded and exhibited significant inhibition.


Assuntos
Alcaligenes/metabolismo , Fenóis/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/metabolismo , Purificação da Água/métodos , Biodegradação Ambiental , Metabolismo dos Carboidratos/fisiologia , Cromatografia Líquida de Alta Pressão , Concentração de Íons de Hidrogênio , Cinética , Espectrofotometria Ultravioleta , Temperatura
14.
Bioresour Technol ; 198: 340-50, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26407348

RESUMO

A freshwater green algae Chlorella pyrenoidosa (C. pyrenoidosa) was cultured in outdoors using the diluted anaerobically digested activated sludge (ADAS). The outdoors batch culture in every season showed that C. pyrenoidosa can grow normally under natural conditions in the diluted ADAS (STE/ADAS=1.5/1, 3/1 and 5/1, v/v). Seasonal changes of environmental conditions significantly affected biomass growth and nutrient removal. Optimal biomass growth and nutrient removal was achieved at STE/ADAS=1.5/1 during summer culture, harvesting a maximum biomass concentration of 1.97 ± 0.21 g/L, average biomass productivity of 291.52 ± 33.74 g/m(3)/day (maximum value of 573.10 ± 41.82) and average lipids productivity of 37.49 ± 5.26 g/m(3)/day (maximum value of 73.70 ± 9.75); simultaneously, the microalgae growth effectively removed nutrients from the wastewater, including 105.6 ± 17.1 mg CODCr/L/day, 36.8 ± 6.1mg N/L/day and 6.1 ± 1.1 mg P/L/day.


Assuntos
Anaerobiose/fisiologia , Biomassa , Chlorella/crescimento & desenvolvimento , Esgotos/microbiologia , Técnicas de Cultura Celular por Lotes , Lipídeos , Águas Residuárias/análise
15.
Bioresour Technol ; 185: 40-8, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25746477

RESUMO

Microalgae cultivation using wastewater might be a suitable approach to support sustainable large-scale biomass production. Its compelling characteristics included the recycling of nutrients and water resources, reducing carbon emissions and harvesting available biomass. In outdoor batch and continuous cultures, Chlorella pyrenoidosa completely adapted to anaerobic digested starch processing wastewater and was the dominant microorganism in the photobioreactor. However, seasonal changes of environmental conditions significantly influenced biomass growth and lipid production. The long-term outdoor operation demonstrated that the biomass concentration and productivity in continuous operations at different hydraulic retention times (HRTs) can be successfully predicted using the kinetic growth parameters obtained from the batch culture. A moderate HRT (4days) in the summer provided the best microalgae and lipid production and achieved relatively high biomass concentrations of 1.29-1.62g/L, biomass productivities of 342.6±12.8mg/L/d and lipids productivities of 43.37±7.43mg/L/d.


Assuntos
Técnicas de Cultura Celular por Lotes/métodos , Reatores Biológicos/microbiologia , Chlorella/fisiologia , Amido/metabolismo , Águas Residuárias/microbiologia , Anaerobiose/fisiologia , Proliferação de Células/fisiologia , Sobrevivência Celular/fisiologia , Projetos Piloto
16.
J Environ Sci (China) ; 15(6): 757-61, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14758892

RESUMO

A group function relation curve between flux (J) and bulk phase concentration of substrate (S) was set up. The biodegradation kinetic of organic compounds of acrylic fiber wastewater in biofilm is studied (the treatment technology is coagulation/sedimentation-anoxic/aerobic biofilm process), and the results showed that the concentration of non-degradation pollutants in effluent is 77 mg/L. In aerobic zone, the half-rate constant is 72.84 mg/L, the maximum removal rate of organic compounds at unit area filler is very low, 0.089 g/(m2 x d), which corresponds to the fact that there are some biorefractory compounds in the wastewater.


Assuntos
Biofilmes , Modelos Químicos , Compostos Orgânicos/metabolismo , Eliminação de Resíduos Líquidos/métodos , Poluentes da Água/análise , Resinas Acrílicas/química , Biodegradação Ambiental , Cinética
17.
Environ Sci Pollut Res Int ; 21(9): 5827-35, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24443047

RESUMO

Use of animal manure is a main source of veterinary pharmaceuticals (VPs) in soil and groundwater through a series of migration processes. The sorption-desorption and transport of four commonly used VPs including trimethoprim (TMP), sulfapyridine, sulfameter, and sulfadimethoxine were investigated in three soil layers taken from an agricultural field in Chongming Island China and two types of aqueous solution (0.01 M CaCl2 solution and wastewater treatment plant effluent). Results from sorption-desorption experiments showed that the sorption behavior of selected VPs conformed to the Freundlich isotherm equation. TMP exhibited higher distribution coefficients (K d = 6.73-9.21) than other sulfonamides (K d = 0.03-0.47), indicating a much stronger adsorption capacity of TMP. The percentage of desorption for TMP in a range of 8-12 % is not so high to be considered significant. Low pH (

Assuntos
Agricultura , Antibacterianos/análise , Poluentes do Solo/análise , Solo/química , Sulfonamidas/análise , Trimetoprima/análise , Adsorção , Animais , China , Concentração de Íons de Hidrogênio , Cinética , Esterco , Modelos Químicos
18.
Sci Rep ; 4: 4841, 2014 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-24788080

RESUMO

Environmental pollution by emerging contaminants, e.g. pharmaceuticals, has become a matter of widespread concern in recent years. We investigated the membrane transport of diclofenac and its toxic effects on gene expression and the development of zebrafish embryos. The association of diclofenac with the embryos conformed to the general partition model at low concentration, the partition coefficient being 0.0033 ml per embryo. At high concentration, the interaction fitted the Freundlich model. Most of the diclofenac remained in the extracellular aqueous solution with less than 5% interacting with the embryo, about half of which was adsorbed on the membranes while the rest entered the cytoplasm. Concentrations of diclofenac over 10.13 µM were lethal to all the embryos, while 3.78 µM diclofenac was teratogenic. The development abnormalities at 4 day post treatment (dpt) include shorter body length, smaller eye, pericardial and body edema, lack of liver, intestine and circulation, muscle degeneration, and abnormal pigmentation. The portion of the diclofenac transferred into the embryo altered the expression of certain genes, e.g. down-regulation of Wnt3a and Gata4 and up-regulation of Wnt8a. The alteration of expression of such genes or the regulation of downstream genes could cause defects in the cardiovascular and nervous systems.


Assuntos
Diclofenaco/toxicidade , Regulação da Expressão Gênica/efeitos dos fármacos , Peixe-Zebra/genética , Animais , Anti-Inflamatórios não Esteroides/toxicidade , Ecotoxicologia , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Desenvolvimento Embrionário/genética , Exposição Ambiental/efeitos adversos , Poluentes Ambientais/toxicidade , Fatores de Tempo
19.
Anal Chim Acta ; 758: 93-100, 2013 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-23245900

RESUMO

A novel multi-templates molecularly imprinted polymer (MIP), using acidic pharmaceuticals mixture (ibuprofen (IBP), naproxen (NPX), ketoprofen (KEP), diclofenac (DFC), and clofibric acid (CA)) as the template, was prepared as solid-phase extraction (SPE) material for the quantitative enrichment of acidic pharmaceuticals in environmental samples and off-line coupled with liquid chromatography-mass spectrometry (LC/MS/MS). Washing solvent was optimized in terms of kind and volume for removing the matrix constituents nonspecifically adsorbed on the MIP. When 1L of water sample spiked at 1µg/L was loaded onto the cartridge, the binding capacity of the MIP cartridge were 48.7µg/g for KEP, 60.7µg/g for NPX, 52µg/g for CA, 61.3µg/g for DFC and 60.7µg/g for IBP, respectively, which are higher than those of the commercial single template MIP in organic medium (e.g. toluene) reported in the literature. Recoveries of the five acidic pharmaceuticals extracted from 1L of real water samples such as lake water and wastewater spiked at 1µg/L were more than 95%. The recoveries of acidic pharmaceuticals extracted from 10-g sediment sample spiked at the 10ng/g level were in the range of 77.4-90.6%. To demonstrate the potential of the MIP obtained, a comparison with commercial C18 SPE cartridge was performed. Molecularly imprinted solid-phase extraction (MISPE) cartridge showed higher recoveries than commercial C18 SPE cartridge for acidic pharmaceuticals. These results showed the suitability of the MISPE method for the selective extraction of a group of structurally related compounds such as acidic pharmaceuticals.


Assuntos
Ácidos/isolamento & purificação , Sedimentos Geológicos/análise , Impressão Molecular , Preparações Farmacêuticas/isolamento & purificação , Extração em Fase Sólida/métodos , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Cromatografia Líquida , Lagos/análise , Polímeros/química , Sensibilidade e Especificidade , Esgotos/análise
20.
Carbohydr Polym ; 97(2): 809-16, 2013 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-23911519

RESUMO

A novel magnetic-molecularly imprinted polymer (MMIP) based on chitosan-Fe3O4 has been synthesized for fast separation of carbamazepine (CBZ) from water. During polymerization, the modified chitosan-Fe3O4 was used not only as supporter but also as functional monomer. The properties of obtained MMIP were characterized by scanning electron and transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectra, thermo-gravimetric analysis and so on. The sorption equilibrium data was well described by Freundlich isotherm model and the increase in the temperature generated an increase in the sorption amount, indicating endothermic nature of adsorption process. Sorption kinetics followed the pseudo-second-order model. The feasibility of selective sorption of CBZ from real water by the MMIP was analyzed by using spiked real water samples. The result showed that the sorption capacity of MMIP has no obvious decrease in different water samples whereas there was obvious decline in the sorption amount of the MNIP.


Assuntos
Carbamazepina/isolamento & purificação , Quitosana/química , Compostos Férricos/química , Magnetismo , Impressão Molecular , Polímeros/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Cinética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Reciclagem , Temperatura , Termogravimetria
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