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1.
Chemosphere ; 357: 141920, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38636914

RESUMEN

Antimony contamination from textile industries has been a global environmental concern and the existing treatment technologies could not reduce Sb(V) to meet the discharge standards. To overcome this shortcoming, ferric flocs were introduced to expedite the biological process for enhanced Sb(V) removal in wastewater treatment plant (WWTP). For this purpose, a series of laboratorial-scale sequential batch reactor activated sludge processes (SBRs) were applied for Sb(V) removal with varied reactor conditions and the transformation of Fe and Sb in SBR system was investigated. Results showed a significant improvement in Sb(V) removal and the 20 mg L-1 d-1 iron ions dosage and iron loss rate was found to be only 15.2%. The influent Sb(V) concentration ranging 153-612 µg L-1 was reduced to below 50 µg L-1, and the maximum Sb(V) removal rate of the enhanced system reached about 94.3%. Furthermore, it exhibited high stability of Sb(V) removal in the face of antimonate load, Fe strike and matrix change of wastewater. Sludge total Sb determination and capacity calculation revealed decreasing in Sb adsorption capacity and desorption without fresh Fe dosage. While sludge morphology analysis demonstrated the aging and crystallization of iron hydroxides. These results verify the distinct effects of fresh iron addition and iron aging on Sb(V) removal. High-throughput gene pyrosequencing results showed that the iron addition changed microbial mechanisms and effect Fe oxidized bacterial quantity, indicating Sb(V) immobilization achieved by microbial synergistic iron oxidation. The present study successfully established a simple and efficient method for Sb(V) removal during biological treatment, and the modification of biological process by iron supplement could provide insights for real textile wastewater treatment.


Asunto(s)
Antimonio , Aguas del Alcantarillado , Eliminación de Residuos Líquidos , Aguas Residuales , Contaminantes Químicos del Agua , Aguas Residuales/química , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo , Aguas del Alcantarillado/química , Aguas del Alcantarillado/microbiología , Antimonio/química , Hierro/química , Adsorción , Industria Textil , Compuestos Férricos/química , Reactores Biológicos/microbiología , Textiles , Biodegradación Ambiental , Aerobiosis
2.
Chemosphere ; 338: 139612, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37482312

RESUMEN

The ubiquitous heavy metal(loid)s (HMs) contamination has triggered great concern about food safety, while sequestration and separation of trace HMs from herbal extracts still calls for appropriate sorbent materials. In this work, gum acacia was modified by cysteine to form a cysteine-acacia intermolecular complex (Cys-GA complex) via facile mechanochemical synthesis, aiming at capturing multiple HMs simultaneously. Preliminary screening confirms the superiority of Cys-CA complex for both cationic and anionic HMs, and determines an optimum Cys/GA mass ratio of 9:1 to achieve high removal capacities for Pb(II) (938 mg g-1), Cd(II) (834 mg g-1), As(V) (496 mg g-1), and Cr(VI) (647 mg g-1) in simulated aqueous solution. The analysis on HMs-exhausted Cys-GA complex indicates that Pb(II), As(V), and Cr(VI) tend to be removed through chelation, electrostatic attraction, and reduction, while Cd(II) can only be chelated or adsorbed by electrostatic interaction. The batch experiments on commercial herbal (e.g. Panax ginseng, Glycine max, Sophora flavescens, Gardenia jasminoides, Cyclocarya paliurus, and Bamboo leaf) extracts indicate that Cys-GA complex can reduce HMs concentration to attain acceptable level that comply with International Organization for Standardization, with negligible negative effect on its active ingredients. This work provides a practical and convenient strategy to purify HMs-contaminated foods without introducing secondary pollution.


Asunto(s)
Cisteína , Metales Pesados , Goma Arábiga , Cadmio , Plomo , Metales Pesados/análisis , Extractos Vegetales , Medición de Riesgo
3.
J BUON ; 26(4): 1355-1364, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34564992

RESUMEN

PURPOSE: Sorafenib combined with transcatheter arterial chemoembolization (TACE) is one of the common methods in the clinical treatment of advanced hepatocellular carcinoma (HCC), but its efficacy and safety are still controversial. Therefore, we used meta-analysis to evaluate the efficacy and safety of sorafenib combined with TACE in the treatment of advanced HCC. METHODS: Up to March 14, 2021, the databases of PubMed, EMBASE, Cochrane Library, CNKI and Wanfang were searched, and the randomized controlled clinical trials (RCTs) of sorafenib combined with TACE in the treatment of primary HCC were included. Two researchers independently screened the literature, extracted data and evaluated the quality according to the inclusion and exclusion criteria. Revman5.4 software was used for meta-analysis. RESULTS: A total of 3076 patients were included in 23 studies, including sorafenib combined with TACE group (n=1542) and TACE group (n=1534). The results of meta-analysis showed that sorafenib combined with TACE could increase the objective response rate (ORR) (RR=1.35, 95%CI: 1.24-1.48, p<0.00001), disease control rate (DCR) (RR=1.19, 95%CI: 1.11-1.28, p<0.00001), prolong the time of disease progression (TTP) (HR=0.80, 95%CI: 0.70-0.92, p=0.001), reduce the expression level of alpha-fetoprotein (AFP) (SMD=2.01, 95%CI: 1.27-2.75, p<0.00001) and vascular endothelial growth factor (VEGF) (SMD=2.62, 95% CI: 1.35-3.90, p<0.0001) in serum. However, the overall survival (OS) was not prolonged (HR=0.86, 95%CI: 0.73-1.02, p=0.09). The incidences of fatigue, diarrhea, elevated bilirubin, skin reaction of hands and feet, rash, hypertension and oral mucosal inflammation in sorafenib combined with TACE group were higher than those in TACE group (p<0.05). CONCLUSION: Sorafenib combined with TACE has some clinical benefits compared with TACE alone, but it does not seem to prolong the OS of patients with HCC, and the incidence of adverse reactions is higher, so more high-quality RCTs are needed to further study the efficacy of the combination regimen.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/terapia , Quimioembolización Terapéutica , Neoplasias Hepáticas/terapia , Sorafenib/uso terapéutico , Antineoplásicos/efectos adversos , Carcinoma Hepatocelular/patología , Quimioembolización Terapéutica/métodos , Terapia Combinada , Arteria Hepática , Humanos , Neoplasias Hepáticas/patología , Sorafenib/efectos adversos , Resultado del Tratamiento
4.
Medicine (Baltimore) ; 97(34): e11978, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-30142830

RESUMEN

BACKGROUND: The clinical application has widespread disagreement on the different regimens of neoadjuvant chemotherapy (NCT) in the treatment of locoregionally advanced nasopharyngeal carcinoma (NPC). We conducted a network meta-analysis (NMA) to evaluate the efficacy of the different NCT regimens in the treatment of NPC. METHODS: A systematic literature search was performed using PubMed, Embase, and Cochran Library. Totally, 31 randomized controlled trials (RCTs) (n = 4062) met study selection criteria and were incorporated in this NMA study. RESULTS: Our study showed that certain NCT regimens improved the prognosis of patients, and found out the relative best solution for each endpoint, such as paclitaxel, carboplatin, and gemcitabine for 1-year overall survival (OS) rate, cisplatin, calcium folinate, and 5-fluorouracil for 2-year OS rate, vinorelbine and cisplatin (NP) for 3-year OS rate, cyclophosphamide, cisplatin, and 5-fluorouracil for 5-year OS rate, NP for complete remission rate, cisplatin and gemcitabine for overall remission rate of the primary tumor. In addition, for certain grade 3 and above toxicity, the results of the NMA reflected certain NCT regimens can reduce toxicity of chemoradiotherapy (CRT) to a minimum, such as NP for anemia, mucositis, and thrombocytopenia, paclitaxel, epirubicin, and cisplatin for neutropenia and skin toxicity. CONCLUSION: Our NMA showed that certain cisplatin-based NCT regimens improved the prognosis of patients with NPC and reduced the toxicity of CRT. However, in view of survival rate and response rate, the best NCT regimen is not entirely consistent. Therefore, which NCT regimen will benefit most patients will need further explored.


Asunto(s)
Antineoplásicos/uso terapéutico , Carcinoma/tratamiento farmacológico , Cisplatino/uso terapéutico , Neoplasias Nasofaríngeas/tratamiento farmacológico , Terapia Neoadyuvante/métodos , Adulto , Carcinoma/mortalidad , Quimioradioterapia/métodos , Quimioradioterapia/mortalidad , Quimioterapia Adyuvante/métodos , Quimioterapia Adyuvante/mortalidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas/mortalidad , Terapia Neoadyuvante/mortalidad , Metaanálisis en Red , Pronóstico , Tasa de Supervivencia , Resultado del Tratamiento
5.
Bioresour Technol ; 247: 36-43, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28946092

RESUMEN

Microalgal wastewater treatment has been considered as one of the most promising measures to treat nitrogen and phosphorus in the municipal wastewater. While the municipal wastewater provides sufficient nitrogen and phosphorus for microalgal growth, the microalgae still faces serious biological contamination caused by bacteria in wastewater. In this study, the commercial granular activated carbon (GAC) was added into the simulated municipal wastewater to avoid the influence of bacteria on the growth of microalgae. The extracellular organic matter (EOM) in microalgal broth was then characterized to enlighten the role of GAC in reducing the bioavailability of EOM. The results showed that the GAC addition could increase the dry weight of microalgae from 0.06mgL-1 to 0.46mgL-1 under the condition of bacterial inoculation. The GAC could mitigate bacterial contamination mainly due to its adsorption of both bacteria and EOM that might contain algicidal extracellular substances. Moreover, compared to the control group, the GAC addition could mitigate the microalgal lysis caused by bacteria and thus greatly reduce the bioavailability of EOM from 2.80mgL-1 to 0.61mgL-1, which was beneficial for the improvement of biostability and reuse of effluent after the microalgal harvesting.


Asunto(s)
Carbón Orgánico , Microalgas , Biomasa , Carbono , Fósforo , Aguas Residuales
6.
Zhongguo Zhong Yao Za Zhi ; 41(9): 1596-1601, 2016 May.
Artículo en Chino | MEDLINE | ID: mdl-28891605

RESUMEN

The paper is aimed to study the distribution, population density, soil conditions and community characteristics of accompanying plants' in Enshi sub-regional different areas, with a typical habitats investigation method. The results showed that the wild Panax japonicus mainly distributed in moist places under the forests, by streams, or secondary forests of high grass, within east longitude 29°-30°, north latitude 108°-110°and about 1 000-15 00 meters above sea level. The soils were mainly tide soil and humus with yellow-brown soil, yellow soil and red soil, and the humus thickness was5-30 centimeter, pH 6.0-6.8, the moisture content of 16.8%-24.2%, soil bulk density of 1.39-2.12. Its geographical vegetation types were mainly evergreen coniferous forest, evergreen-deciduous mixture broad leaved forest and evergreen coniferous forest mixed deciduous broad-leaved forest, including three levels community structure of arbors, shrubs and herbaceous; Its accompanying plants reached 86 families, 118 genera, 134 species of seed plants, the arbors included 15 families, 21 genera, 26 species and the dominant species community mainly Pinaceae such as Pinus massoniana, P. tabuliformis, P. henryi and Taxodiaceae such as Cunninghamia lanceolata, Cryptomeria fortunei etc. The shrubs included 39 families, 54 genera, 62 species with the dominant species such as Camellia oleifera, Kalopanax septemlobus, Akebia trifoliata, Trachycarpusfortunei, Rhamnus globosa, Smilax corbularia and so on. The herbaceous included 32 families, 43 genera, 46 species, and Ferns such as the black-footed Dryopteris, Dryopteris crassirhizom, Coniogramme affinis, Polystichum tripteron, Adiantum pedatum, Lunathyrium acrostichoides, Woodsia ilvensis and Woodwardia japonica were dominant species. The cover layer covered a large number of lichens and mosses. The wild P. japonicus can be found among the P. massoniana, P. tabuliformis, P. henryi, lichens and mosses. These may indicate that the wild P. japonicusin Enshi requires higher demands on the ecological environment, its accompanying plants are mainly the tree layer-shrub layer-herb layer, and vertical structure is obvious. The study provides a basis for domestication and conservation of P. japonicus resources.


Asunto(s)
Ecosistema , Panax/crecimiento & desarrollo , China , Suelo , Árboles
7.
Bioresour Technol ; 193: 68-75, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26117237

RESUMEN

Chlorella vulgaris, a marine microalgae strain adaptable to 0-50 g L(-1) of salinity, was selected for studying the coupling system of saline wastewater treatment and lipid accumulation. The effect of total nitrogen (T N) concentration was investigated on algal growth, nutrients removal as well as lipid accumulation. The removal efficiencies of TN and total phosphorus (TP) were found to be 92.2-96.6% and over 99%, respectively, after a batch cultivation of 20 days. To illustrate the response of lipid accumulation to nutrients removal, C. vulgaris was further cultivated in the recycling experiment of tidal saline water within the photobioreactor. The lipid accumulation was triggered upon the almost depletion of nitrate (<5 mg L(-1)), till the final highest lipid content of 40%. The nitrogen conversion in the sequence of nitrate, nitrite, and then to ammonium in the effluents was finally integrated with previous discussions on metabolic pathways of algal cell under nitrogen deficiency.


Asunto(s)
Chlorella vulgaris/metabolismo , Lípidos/fisiología , Microalgas/metabolismo , Nitratos/metabolismo , Cloruro de Sodio/metabolismo , Aguas Residuales/química , Compuestos de Amonio/metabolismo , Redes y Vías Metabólicas/fisiología , Nitritos/metabolismo , Nitrógeno/metabolismo , Fósforo/metabolismo , Fotobiorreactores , Eliminación de Residuos Líquidos/métodos
8.
Bioresour Technol ; 190: 257-63, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25958150

RESUMEN

The combination of tertiary wastewater treatment and microalgal lipid production is considered to be a promising approach to water eutrophication as well as energy crisis. To intensify wastewater treatment and microalgal biofuel production, the effect of organic and inorganic carbon on algal growth and nutrient removal of Scenedesmus obliquus were examined by varying TOC (total organic carbon) concentrations of 20-120mgL(-1) in wastewater and feeding CO2 concentrations in the range of 0.03-15%, respectively. The results showed that the maximal biomass and average lipid productivity were 577.6 and 16.7mgL(-1)d(-1) with 5% CO2 aeration. The total nitrogen, total phosphorus and TOC removal efficiencies were 97.8%, 95.6% and 59.1% respectively within 6days when cultured with real secondary municipal wastewater. This work further showed that S. obliquus could be utilized for simultaneous organic pollutants reduction, N, P removal and lipid accumulation.


Asunto(s)
Dióxido de Carbono/metabolismo , Metabolismo de los Lípidos/fisiología , Scenedesmus/fisiología , Aguas Residuales/microbiología , Contaminantes Químicos del Agua/química , Purificación del Agua/métodos , Biodegradación Ambiental , Biocombustibles/microbiología , Carbono/metabolismo , Proliferación Celular/fisiología
9.
Exp Biol Med (Maywood) ; 240(9): 1197-204, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25432983

RESUMEN

Metallothionein (MT) gene therapy leads to resolution of liver fibrosis in mouse model, in which the activation of collagenases is involved in the regression of liver fibrosis. MT plays a critical role in zinc sequestration in the liver suggesting its therapeutic effect would be mediated by zinc. The present study was undertaken to test the hypothesis that zinc supplementation suppresses liver fibrosis. Male Kunming mice subjected to bile duct ligation (BDL) resulted in liver fibrosis as assessed by increased α-smooth muscle actin (α-SMA) and collagen I production/deposition in the liver. Zinc supplementation was introduced 4 weeks after BDL surgery via intragastric administration once daily for 2 weeks resulting in a significant reduction in the collagen deposition in the liver and an increase in the survival rate. Furthermore, zinc suppressed gene expression of α-SMA and collagen I and enhanced the capacity of collagen degradation, as determined by the increased activity of total collagenases and elevated mRNA and protein levels of MMP13. Therefore, the results demonstrate that zinc supplementation suppresses BDL-induced liver fibrosis through both inhibiting collagen production and enhancing collagen degradation.


Asunto(s)
Cirrosis Hepática Experimental/prevención & control , Zinc/administración & dosificación , Actinas/genética , Actinas/metabolismo , Animales , Conductos Biliares , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colagenasas/genética , Colagenasas/metabolismo , Suplementos Dietéticos , Modelos Animales de Enfermedad , Ligadura , Hígado/efectos de los fármacos , Hígado/metabolismo , Hígado/patología , Cirrosis Hepática Experimental/etiología , Cirrosis Hepática Experimental/metabolismo , Masculino , Metaloproteinasa 13 de la Matriz/genética , Metaloproteinasa 13 de la Matriz/metabolismo , Ratones , ARN Mensajero/genética , ARN Mensajero/metabolismo , Transcriptoma , Zinc/sangre , Zinc/metabolismo
10.
PLoS One ; 9(1): e85575, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24475045

RESUMEN

Soil biogeochemical processes and the ecological stability of wetland ecosystems under global warming scenarios have gained increasing attention worldwide. Changes in the capacity of microorganisms to maintain stoichiometric homeostasis, or relatively stable internal concentrations of elements, may serve as an indicator of alterations to soil biogeochemical processes and their associated ecological feedbacks. In this study, an outdoor computerized microcosm was set up to simulate a warmed (+5°C) climate scenario, using novel, minute-scale temperature manipulation technology. The principle of stoichiometric homeostasis was adopted to illustrate phosphorus (P) biogeochemical cycling coupled with carbon (C) dynamics within the soil-microorganism complex. We hypothesized that enhancing the flux of P from soil to water under warming scenarios is tightly coupled with a decrease in homeostatic regulation ability in wetland ecosystems. Results indicate that experimental warming impaired the ability of stoichiometric homeostasis (H) to regulate biogeochemical processes, enhancing the ecological role of wetland soil as an ecological source for both P and C. The potential P flux from soil to water ranged from 0.11 to 34.51 mg m(-2) d(-1) in the control and 0.07 to 61.26 mg m(-2) d(-1) in the warmed treatment. The synergistic function of C-P acquisition is an important mechanism underlying C∶P stoichiometric balance for soil microorganisms under warming. For both treatment groups, strongly significant (p<0.001) relationships fitting a negative allometric power model with a fractional exponent were found between n-HC∶P (the specialized homeostatic regulation ability as a ratio of soil highly labile organic carbon to dissolved reactive phosphorus in porewater) and potential P flux. Although many factors may affect soil P dynamics, the n-HC∶P term fundamentally reflects the stoichiometric balance or interactions between the energy landscape (i.e., C) and flow of resources (e.g., N and P), and can be a useful ecological tool for assessing potential P flux in ecosystems.


Asunto(s)
Homeostasis/fisiología , Modelos Biológicos , Fósforo/metabolismo , Microbiología del Suelo , Suelo/química , Temperatura , Humedales , Fenómenos Ecológicos y Ambientales , Calentamiento Global
11.
Metallomics ; 6(3): 554-9, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24343031

RESUMEN

Copper chaperones are critical regulators of intracellular copper metabolism and distribution. The present study was undertaken to investigate the effects of changes in copper concentrations on the abundance of copper chaperones. Human umbilical vein endothelial cells (HUVECs) were treated with siRNA targeting copper transporter 1 (CTR1) or tetraethylenepentamine (TEPA) to decrease, or with copper sulfide to increase, intracellular copper concentrations, assayed using an atomic absorption spectrophotometer. Western blot analyses showed that CTR1 silencing or TEPA treatment increased the protein levels of copper chaperone ATOX1 and copper chaperone for superoxide dismutase 1 (CCS-1), but decreased copper chaperone for cytochrome c oxidase (COX17). In contrast, copper supplementation decreased the protein levels of ATOX1 and CCS-1 and increased COX17. Real-time RT-PCR analyses found no difference in the mRNA levels of the copper chaperones examined under the conditions defined above. This study thus demonstrated that changes in copper concentrations alter the protein levels, but not the mRNA levels, of copper chaperones, suggesting a role of copper in the post-translational modification of these proteins.


Asunto(s)
Proteínas Portadoras/metabolismo , Proteínas de Transporte de Catión/metabolismo , Cobre/metabolismo , Células Endoteliales de la Vena Umbilical Humana/metabolismo , Chaperonas Moleculares/metabolismo , ARN Mensajero/genética , Proteínas Portadoras/genética , Proteínas de Transporte de Catión/genética , Proteínas Transportadoras de Cobre , Transportador de Cobre 1 , Humanos , Chaperonas Moleculares/genética , Interferencia de ARN , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética
12.
Chemosphere ; 90(6): 1794-804, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22999304

RESUMEN

Global warming is increasingly challenging for wetland ecological function. A temperature controlled microcosm system was developed to simulate climate change scenarios of an ambient temperature (control) and an elevated temperature (+5 °C). The effects and associated mechanisms of warming on phosphorus (P) fluxes at the sediment-water interface of six subtropical wetlands were investigated. The results indicated that P fluxes were generally enhanced under the experimental warming as measured by higher P concentrations in the porewater and overlying water as well as higher benthic P fluxes. The release of P from sediment to porewater occurred more strongly and quickly in response to experimental warming compared to the subsequent upward transfer into overlying water. The average accumulative benthic P output from the tested wetlands under the experimental warming was greater by 12.9 µg cm(-2) y(-1) (28%) for total P and 8.26 µg cm(-2) y(-1) (25%) for dissolved reactive P, compared to the ambient scenarios. Under warming the redistribution of P fractions in sediments occurred with greater NH(4)Cl-P and lower BD-P (extracted by a bicarbonate buffered dithionite solution) accompanied by greater NaOH-P. The higher temperature enhanced total phospholipid fatty acids. A shift in the microbial community was also observed with a relative dominance of fungi (a 4.7% increase) and a relative decline (by 18%) in bacterial abundance, leading to the higher secretion of phosphatase. Comparing between wetlands, the potential P fluxes in the nutrient-enriched wetlands were less impacted by warming than the other wetland types investigated. Thus wetlands characterized by low or medium concentrations of P in sediments were more susceptible to warming compared to P-rich wetlands.


Asunto(s)
Monitoreo del Ambiente , Sedimentos Geológicos/química , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Humedales , Ecosistema , Temperatura , Contaminación Química del Agua/estadística & datos numéricos
13.
Appl Environ Microbiol ; 78(21): 7652-61, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22923398

RESUMEN

Rising climate temperatures in the future are predicted to accelerate the microbial decomposition of soil organic matter. A field microcosm experiment was carried out to examine the impact of soil warming in freshwater wetlands on different organic carbon (C) pools and associated microbial functional responses. GeoChip 4.0, a functional gene microarray, was used to determine microbial gene diversity and functional potential for C degradation. Experimental warming significantly increased soil pore water dissolved organic C and phosphorus (P) concentrations, leading to a higher potential for C emission and P export. Such losses of total organic C stored in soil could be traced back to the decomposition of recalcitrant organic C. Warming preferentially stimulated genes for degrading recalcitrant C over labile C. This was especially true for genes encoding cellobiase and mnp for cellulose and lignin degradation, respectively. We confirmed this with warming-enhanced polyphenol oxidase and peroxidase activities for recalcitrant C acquisition and greater increases in recalcitrant C use efficiency than in labile C use efficiency (average percentage increases of 48% versus 28%, respectively). The relative abundance of lignin-degrading genes increased by 15% under warming; meanwhile, soil fungi, as the primary decomposers of lignin, were greater in abundance by 27%. This work suggests that future warming may enhance the potential for accelerated fungal decomposition of lignin-like compounds, leading to greater microbially mediated C losses than previously estimated in freshwater wetlands.


Asunto(s)
Bacterias/metabolismo , Carbono/metabolismo , Cambio Climático , Agua Dulce/microbiología , Hongos/metabolismo , Suelo/química , Humedales , Bacterias/clasificación , Bacterias/genética , Biodiversidad , Biomasa , Carbono/química , Catecol Oxidasa/metabolismo , Celulosa/metabolismo , Clima , Ecosistema , Hongos/clasificación , Hongos/genética , Variación Genética , Calefacción , Lignina/metabolismo , Peroxidasa/metabolismo , Fósforo/química , Fósforo/metabolismo , Suelo/análisis , Microbiología del Suelo , Temperatura , beta-Glucosidasa/genética
14.
J Chromatogr Sci ; 50(10): 885-92, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22718742

RESUMEN

A simple, rapid and sensitive liquid chromatography tandem mass spectrometry method is presented for the simultaneous determination of oleanolic acid, p-coumaric acid, ferulic acid, kaemperol and quercetin in rat plasma. Glycyrrhetinic acid was used as an internal standard, and sample pretreatment consisted of a liquid-liquid extraction. Chromatographic separation was achieved on a Gemini 110A C18 column (50 × 2.0 mm i.d., 5 µm) by gradient elution with a mobile phase consisting of methanol, acetonitrile and 0.01% formic acid in water. Tandem mass spectrometric detection was conducted using multiple reaction monitoring under negative ionization mode. Calibration curves offered linear ranges of two orders of magnitude with r > 0.99. The method was validated in terms of matrix effect, intra-day and inter-day precision, accuracy, linearity, specificity and stability. The relative standard deviation of intra-day and inter-day variations ranged from 2.66 to 14.74% and 1.9 to 14.55%. No substantial endogenous interference from blank plasma was observed. The method has been successfully applied to a pharmacokinetic study of Oldenlandia diffusa extract after oral administration in rats.


Asunto(s)
Cromatografía Liquida/métodos , Ácidos Cumáricos/sangre , Flavonoles/sangre , Oldenlandia/química , Ácido Oleanólico/sangre , Extractos Vegetales/farmacocinética , Animales , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacocinética , Estabilidad de Medicamentos , Flavonoles/química , Flavonoles/farmacocinética , Modelos Lineales , Masculino , Ácido Oleanólico/química , Ácido Oleanólico/farmacocinética , Extractos Vegetales/administración & dosificación , Ratas , Ratas Sprague-Dawley , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Espectrometría de Masas en Tándem/métodos
15.
Bioresour Technol ; 102(3): 2455-61, 2011 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-21123052

RESUMEN

The alkaline phosphatase activities (APA) and phosphorus fractions in activated sludge during wastewater treatment were studied. Our results showed that the phosphorus concentration and fractions in activated sludge were highly correlated with the characteristics of influents. Inorganic phosphorus (IP) and non-apatite inorganic phosphorus (NAIP) were the main phosphorus fractions of sludge. A larger phosphorus concentration was found in activated sludge due to the more readily mobilizable and bio-available forms. The APA in sludge was directly correlated with mixed liquor suspended solids (MLSS) in activated sludge. The APA in the sludge is implicated the depletion of organic phosphorus forms in sludge, whilst also implying its less inhibition of inorganic phosphorus in sludge. The APA and phosphorus fractions in different sludge samples from the same wastewater treatment plant were quite stable. This stability shows their tight interactions in sludge.


Asunto(s)
Fosfatasa Alcalina/química , Fósforo/química , Aguas del Alcantarillado/análisis , Aguas del Alcantarillado/química , Activación Enzimática
16.
Chemosphere ; 56(10): 889-94, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15268954

RESUMEN

Electro-coagulation was used to treat refectory wastewater with high oil and grease contents. Different operational conditions were examined, including pH, current density, reaction time, conductivity, electrode distance and inlet concentration. The optimum current density was 10-14 A m(-2) within 30 min depending on the wastewater properties tested. Conductivity had little effect on the treatment efficiency. Although the addition of extra salts (e.g., sodium chloride) to the wastewater did not help increase the pollutant removal efficiency, it could save the power consumption significantly. The COD(Cr) and oil removal efficiency descended with increasing electrode distance. The optimal electrode distance was determined to be 10 mm for this equipment in consideration of the treatment cost and efficiency together. The pH effect on the performance of the electro-coagulation process was not very significant in the range of 3-10. The removal efficiency of oil and COD(Cr) under normal condition exceeded 95% and 75%, respectively.


Asunto(s)
Electrocoagulación/métodos , Petróleo , Eliminación de Residuos Líquidos/métodos , Contaminantes Químicos del Agua , Conductividad Eléctrica , Electrodos , Concentración de Iones de Hidrógeno , Factores de Tiempo
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