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1.
Transfusion ; 60(7): 1579-1589, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32415759

RESUMO

BACKGROUND: Platelet transfusion is associated with logistical problems with the national storage guidelines of platelets. This results in decreased function in vivo as a result of the platelet storage lesion, and complications such as allergic or hemolytic reactions and thrombosis. We evaluated a new, freshly prepared platelet modified lysate (PML) product designed to be more procoagulant than fresh and stored platelets. METHODS: Fresh platelets were concentrated, sonicated, and centrifuged to produce PML. Samples of both washed and unwashed PML were evaluated for particle size, concentration, and activity, and then tested for clot kinetics and thrombin generation. PML samples were also stored at various temperatures for durations up to 6 months and evaluated for clot kinetics and thrombin generation throughout. RESULTS: PML showed significantly higher concentration of platelet microparticles, increased procoagulant properties, and increased thrombin generation as compared to fresh and stored platelets. In addition, PML maintained its clot kinetics over a 6-month storage period with variable storage conditions. CONCLUSIONS: The newly proposed PML product is more procoagulant, stable, and has additional potential applications than currently available platelet products. Further studies will be performed to assess its functions in vivo and to assess thrombotic potential.


Assuntos
Coagulação Sanguínea/efeitos dos fármacos , Plaquetas/química , Micropartículas Derivadas de Células/química , Coagulantes , Coagulantes/química , Coagulantes/farmacologia , Avaliação Pré-Clínica de Medicamentos , Humanos , Transfusão de Plaquetas
2.
Chem Commun (Camb) ; 55(78): 11790-11793, 2019 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-31524903

RESUMO

Balancing and neutralizing heparin dosing after surgeries and hemodialysis treatment is of great importance in medical and clinical fields. In this study, a series of new amphiphilic multi-charged cyclodextrins (AMCD)s as anti-heparin coagulants were designed and synthesized. The AMCD assembly was capable of selective heparin binding through multivalent bonding and showed a better neutralizing effect towards both unfractionated heparin and low molecular weight heparin than protamine in plasma. Meanwhile, an AMCD and vitamin K (VK) co-assembly was prepared to realize heparin-responsive VK release and provide a novel VK deficiency treatment for hemodialysis patients. This AMCD-VK co-assembly for heparin neutralization & vitamin K supplementation synergistic coagulation represents a promising candidate as a clinical anti-heparin coagulant.


Assuntos
Coagulantes/química , Ciclodextrinas/química , Vitamina K/química , Coagulantes/metabolismo , Ciclodextrinas/metabolismo , Heparina/química , Heparina/metabolismo , Tempo de Tromboplastina Parcial , Protaminas/química , Protaminas/metabolismo , Espectrofotometria , Vitamina K/metabolismo
3.
Environ Monit Assess ; 189(3): 133, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28247285

RESUMO

The huge quantity of effluent generated in coal washing processes contains large amount of suspended and dissolved solids, clay minerals, coal fines and other impurities associated with raw coal. The present system of recirculation of the effluent is found to be ineffective in removing colloidal fines, which is the major part of the impurities present in washery effluent. Hence, there is a need for the assessment of a better technique for an efficient removal of these impurities. This study deals with detailed characterisation of coal washery effluent and fine particles present in it. For efficient removal of impurities, the suitability of biocoag-flocculation process using Moringa oleifera seed biomass as a natural coagulant was examined. Various doses of M. oleifera ranging from 0.2 to 3 mL/L were used in order to determine the optimal conditions. The impact of the variations in pH of the effluent (2-10), contact time (5-30 min), settlement time (5-50 min), temperature (10-50 °C) and the effluent dilution (1:0-1:5) was also assessed to optimise the treatment process. Post treatment analysis was carried out for determination of the different parameters such as pH, conductivity, turbidity, solids and settling velocity. Excellent reduction in turbidity (97.42%) and suspended solids (97.78%) was observed at an optimum dose of M. oleifera seed coagulant of 0.8 mL/L with an optimum contact time of 15 and at 20 min of settling time. In comparison with very few past studies of M. oleifera in the treatment of coal washery effluent with high dose and inadequate removal, this study stands to be a major highlight with low dose and high removal of the impurities. M. oleifera coagulant is considered to be an environment-friendly material, therefore, its application is recommended for simple and efficient treatment of coal washery effluent.


Assuntos
Coagulantes/química , Carvão Mineral , Monitoramento Ambiental/métodos , Moringa oleifera/química , Sementes/química , Purificação da Água/métodos , Floculação , Geografia , Concentração de Íons de Hidrogênio , Índia , Nefelometria e Turbidimetria , Tamanho da Partícula , Extratos Vegetais/química , Temperatura
4.
Environ Sci Pollut Res Int ; 23(8): 7692-700, 2016 04.
Artigo em Inglês | MEDLINE | ID: mdl-26743649

RESUMO

In this work, to evaluate the effectiveness of the coagulation/flocculation using a natural coagulant, using Moringa oleifera Lam functionalized with magnetic iron oxide nanoparticles, producing flakes that are attracted by an external magnetic field, thereby allowing a fast settling and separation of the clarified liquid, is proposed. The removal efficiency of the parameters, apparent color, turbidity, and compounds with UV254nm absorption, was evaluated. The magnetic functionalized M. oleifera Lam coagulant could effectively remove 90 % of turbidity, 85 % of apparent color, and 50 % for the compounds with absorption at UV254nm, in surface waters under the influence of an external magnetic field within 30 min. It was found that the coagulation/flocculation treatment using magnetic functionalized M. oleifera Lam coagulant was able to reduce the values of the physico-chemical parameters evaluated with reduced settling time.


Assuntos
Coagulantes/química , Imãs/química , Moringa oleifera/química , Extratos Vegetais/química , Sementes/química , Purificação da Água/métodos , Floculação
5.
Shock ; 42(6): 548-53, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25243422

RESUMO

BACKGROUND AND AIMS: Lipid emulsions for parenteral nutrition interfere with immunity and may alter the cell plasma membrane and microparticle release, thus modulating their biological effects. Our aim was to evaluate the effect of two lipid emulsions for parenteral nutrition containing either a mixture of long- and medium-chain triglycerides (LCTs and MCTs) or LCTs only, to assess their role on microparticle release and acute inflammation during septic shock in rats. METHODS AND RESULTS: Septic rats (cecal ligation and puncture) and sham rats were infused with 5% dextrose or a lipid emulsion during 22 h. After 18 h, rats were resuscitated during 4 h and hemodynamic parameters monitored. Circulating microparticles and their phenotype were measured by prothrombinase assay; heart and aorta were collected for Western blotting and electron paramagnetic resonance measurements. No significant effect of lipid emulsions was observed in sham rats. In septic rats, norepinephrine requirements were increased in MCT/LCT-infused rats compared with 5% dextrose- or LCT-infused rats (2.7 ± 0.2 vs. 1.9 ± 0.8 and 1.2 ± 0.3 µg/kg per minute, respectively; P < 0.05) with increased procoagulant microparticle generation (38.6 ± 5.8 vs. 18.8 ± 3.1 and 19.2 ± 3.0 nM equivalent phosphatidylserine [Eq PhtdSer]; P < 0.05), leukocyte- (17.4 ± 3.5 vs. 7.7 ± 1.8 and 6.0 ± 1.1 nM Eq PhtdSer; P < 0.05), platelet- (13.9 ± 2.5 vs. 4.4 ± 0.7 and 5.4 ± 1.3 nM Eq PhtdSer; P < 0.05), and endothelial-derived microparticles (16.9 ± 3.6 vs. 6.4 ± 1.4 and 5.6 ± 0.8 nM Eq PhtdSer; P < 0.05). The mixture of MCTs/LCTs significantly increased cardiac and vascular nitric oxide and superoxide anion production, phosphorylated IκB, and cyclooxygenase 2 expression compared with the lipid emulsion containing only LCTs. CONCLUSIONS: Compared with 5% dextrose, MCT/LCT supplementation during septic shock in rats induced deleterious effects with increased inflammation and cell activation, associated to vascular hyporeactivity. During septic shock, LCT supplementation seemed to be neutral compared with 5% dextrose infusion.


Assuntos
Membrana Celular/metabolismo , Peritonite/fisiopatologia , Choque Séptico/fisiopatologia , Triglicerídeos/efeitos adversos , Animais , Aorta/metabolismo , Coagulantes/química , Espectroscopia de Ressonância de Spin Eletrônica , Emulsões/química , Glucose/química , Hemodinâmica , Inflamação , Lipídeos/química , Masculino , Microesferas , Miocárdio/metabolismo , Óxido Nítrico/química , Soluções de Nutrição Parenteral/química , Fosforilação , Ratos , Ratos Wistar , Choque Séptico/induzido quimicamente , Choque Séptico/metabolismo , Superóxidos/química , Fatores de Tempo , Triglicerídeos/química
6.
Molecules ; 19(3): 3552-69, 2014 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-24662073

RESUMO

Proteolytic enzymes are important macromolecules in the regulation of biochemical processes in living organisms. Additionally, these versatile biomolecules have numerous applications in the industrial segment. In this study we have characterized a protein-rich fraction of Cnidoscolus urens (L.) Arthur leaves, rich in proteolytic enzymes, and evaluated its effects on the coagulation cascade. Three protein-rich fractions were obtained from the crude extract of C. urens leaves by precipitation with acetone. Fraction F1.0 showed higher proteolytic activity upon azocasein, and thus, was chosen for subsequent tests. The proteolytic activity of F1.0 on fibrinogen was dose-dependent and time-dependent. The extract demonstrated procoagulant activity on citrated plasma and reduced the APTT, not exerting effects on PT. Despite the fibrin(ogen)olytic activity, F1.0 showed no defibrinogenating activity in vivo. The fraction F1.0 did not express hemorrhagic nor hemolytic activities. The proteolytic activity was inhibited by E-64, EDTA and in the presence of metal ions, and increased when pretreated with reducing agents, suggesting that the observed activity was mostly due to cysteine proteases. Several bands with proteolytic activity were detected by zymography with gelatin, albumin and fibrinogen. The optimal enzymatic activity was observed in temperature of 60 °C and pH 5.0, demonstrating the presence of acidic proteases. In conclusion, these results could provide basis for the pharmacological application of C. urens proteases as a new source of bioactive molecules to treat bleeding and thrombotic disorders.


Assuntos
Coagulantes/farmacologia , Euphorbiaceae/química , Fibrinolíticos/farmacologia , Peptídeo Hidrolases/metabolismo , Extratos Vegetais/química , Folhas de Planta/química , Animais , Fracionamento Químico , Coagulantes/química , Ativação Enzimática , Euphorbiaceae/enzimologia , Feminino , Fibrinogênio/metabolismo , Fibrinolíticos/química , Humanos , Concentração de Íons de Hidrogênio , Cinética , Masculino , Metais , Camundongos , Tempo de Tromboplastina Parcial , Peptídeo Hidrolases/química , Folhas de Planta/enzimologia , Proteólise/efeitos dos fármacos , Temperatura , Tempo de Trombina
7.
J Environ Sci (China) ; 25(4): 659-69, 2013 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-23923774

RESUMO

The drainage of peatland areas for peat extraction, agriculture or bioenergy requires affordable, simple and reliable treatment methods that can purify waters rich in particulates and dissolved organic carbon. This work focused on the optimisation of chemical purification process for the direct dosage of solid metal salt coagulants. It investigated process requirements of solid coagulants and the influence of water quality, temperature and process parameters on their performance. This is the first attempt to provide information on specific process requirements of solid coagulants. Three solid inorganic coagulants were evaluated: aluminium sulphate, ferric sulphate and ferric aluminium sulphate. Pre-dissolved aluminium and ferric sulphate were also tested with the objective of identifying the effects of in-line coagulant dissolution on purification performance. It was determined that the pre-dissolution of the coagulants had a significant effect on coagulant performance and process requirements. Highest purification levels achieved by solid coagulants, even at 30% higher dosages, were generally lower (5%-30%) than those achieved by pre-dissolved coagulants. Furthermore, the mixing requirements of coagulants pre-dissolved prior to addition differed substantially from those of solid coagulants. The pH of the water samples being purified had a major influence on coagulant dosage and purification efficiency. Ferric sulphate (70 mg/L) was found to be the best performing solid coagulant achieving the following load removals: suspended solids (59%-88%), total organic carbon (56%-62%), total phosphorus (87%-90%), phosphate phosphorus (85%-92%) and total nitrogen (33%-44%). The results show that the use of solid coagulants is a viable option for the treatment of peatland-derived runoff water if solid coagulant-specific process requirements, such as mixing and settling time, are considered.


Assuntos
Coagulantes/química , Metais/química , Sais/química , Solo/química , Eliminação de Resíduos Líquidos , Purificação da Água/métodos , Carbono/análise , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Compostos Orgânicos/análise , Temperatura , Qualidade da Água
8.
Int J Biol Macromol ; 58: 31-6, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23537800

RESUMO

Lectins are carbohydrate recognition proteins. cMoL, a coagulant Moringa oleifera Lectin, was isolated from seeds of the plant. Structural studies revealed a heat-stable and pH resistant protein with 101 amino acids, 11.67 theoretical pI and 81% similarity with a M. oleifera flocculent protein. Secondary structure content was estimated as 46% α-helix, 12% ß-sheets, 17% ß-turns and 25% unordered structures belonging to the α/ß tertiary structure class. cMoL significantly prolonged the time required for blood coagulation, activated partial thromboplastin (aPTT) and prothrombin times (PT), but was not so effective in prolonging aPTT in asialofetuin presence. cMoL acted as an anticoagulant protein on in vitro blood coagulation parameters and at least on aPTT, the lectin interacted through the carbohydrate recognition domain.


Assuntos
Coagulantes/química , Moringa oleifera/química , Extratos Vegetais/química , Lectinas de Plantas/química , Sequência de Aminoácidos , Coagulantes/farmacologia , Humanos , Dados de Sequência Molecular , Tempo de Tromboplastina Parcial , Extratos Vegetais/farmacologia , Lectinas de Plantas/farmacologia , Estabilidade Proteica , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Tempo de Protrombina
9.
J Biomol Struct Dyn ; 31(10): 1182-90, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23163338

RESUMO

The design of novel protein-nanoparticle hybrid systems has applications in many fields of science ranging from biomedicine, catalysis, water treatment, etc. The main barrier in devising such tool is lack of adequate information or poor understanding of protein-ligand chemistry. Here, we establish a new strategy based on computational modeling for protein and precursor linkers that can decorate the nanoparticles. Moringa oleifera (MO2.1) seed protein that has coagulation and antimicrobial properties was used. Superparamagnetic nanoparticles (SPION) with precursor ligands were used for the protein-ligand interaction studies. The molecular docking studies reveal that there are two binding sites, one is located at the core binding site; tetraethoxysilane (TEOS) or 3-aminopropyl trimethoxysilane (APTES) binds to this site while the other one is located at the side chain residues where trisodium citrate (TSC) or Si60 binds to this site. The protein-ligand distance profile analysis explains the differences in functional activity of the decorated SPION. Experimentally, TSC-coated nanoparticles showed higher coagulation activity as compared to TEOS- and APTES-coated SPION. To our knowledge, this is the first report on in vitro experimental data, which endorses the computational modeling studies as a powerful tool to design novel precursors for functionalization of nanomaterials; and develop interface hybrid systems for various applications.


Assuntos
Coagulantes/química , Modelos Moleculares , Nanopartículas/química , Proteínas/química , Sequência de Aminoácidos , Testes de Coagulação Sanguínea , Coagulantes/metabolismo , Ligantes , Nanopartículas de Magnetita/química , Conformação Molecular , Simulação de Acoplamento Molecular , Dados de Sequência Molecular , Nanopartículas/metabolismo , Extratos Vegetais/química , Ligação Proteica , Multimerização Proteica , Proteínas/metabolismo , Propriedades de Superfície , Traqueófitas/química
10.
Water Environ Res ; 83(3): 256-64, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21466073

RESUMO

Oily wastewaters are the most important discharges of gas refineries from an environmental point-of-view. In the present study, treatment of gas refinery oily wastewater by electrocoagulation using aluminum electrodes was investigated. The effects of electrode distance, initial pH, sodium sulfate (Na2SO4) as a supporting electrolyte, polyaluminum chloride dosage as a coagulant aid, and current density on the efficiency of chemical oxygen demand (COD) removal were examined. The results revealed that the COD removal rate increases by applying more current density and polyaluminum chloride and, to a lesser extent, Na2SO4 dosage. The results also showed that 97% COD can be removed at optimum operational conditions. Specific electrical energy consumption could be reduced from 19.48 kWh (kg COD removal)(-1) to 11.057 kWh (kg COD removal)(-1) using Na2SO4 as a supporting electrolyte. Gas chromatographic analysis of raw and treated wastewater also revealed that most normal hydrocarbons (nearly 99%) were removed during the electrocoagulation process.


Assuntos
Eliminação de Resíduos Líquidos/métodos , Poluição da Água/prevenção & controle , Alumínio , Hidróxido de Alumínio/química , Análise da Demanda Biológica de Oxigênio , Coagulantes/química , Eletrocoagulação/métodos , Eletrodos , Eletrólitos/química , Concentração de Íons de Hidrogênio , Irã (Geográfico) , Petróleo , Sulfatos/química
11.
Chemosphere ; 72(11): 1621-35, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18558418

RESUMO

Red mud (RM) is a by-product of bauxite processing via the Bayer process. Its disposal remains an issue of great importance with significant environmental concerns. In the past decades, a lot of research has been done to utilize red mud for environmental-benign applications such as a building material additive and for metal recovery. In recent years, red mud has also been explored for gas cleaning and wastewater treatment. In this paper, we review varying novel applications of red mud as a coagulant and adsorbent for water and gas treatment as well as catalyst for some industrial processes. The environmental compatibility of red mud is discussed. Some directions of future research are also proposed. Red mud presents a promising application in water treatment for removal of toxic heavy metal and metalloid ions, inorganic anions such as nitrate, fluoride, and phosphate, as well as organics including dyes, phenolic compounds and bacteria. In addition, red mud can also be employed as catalysts for hydrogenation, hydrodechlorination and hydrocarbon oxidation. Moreover, leaching and eco-toxicological tests indicate that red mud does not present high toxicity to the environment before or after reuse.


Assuntos
Óxido de Alumínio/química , Coagulantes/química , Conservação dos Recursos Naturais/métodos , Resíduos Industriais , Eliminação de Resíduos/métodos , Adsorção , Catálise
12.
Toxicon ; 51(5): 923-33, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18249434

RESUMO

A novel, basic pro-coagulation metalloprotease (Russell's viper basic coagulant metalloprotease, RVBCMP) with an approximate molecular weight of 15kDa was purified from the venom of Daboia russelli russelli (Russell's viper) from eastern India. RVBCMP exerted dose-dependent coagulation of platelet-poor human plasma; however, RVBCMP possessed less coagulant activity as compared with the coagulant activity of crude Russell's viper venom (RVV). RVBCMP did not show oedema induction, direct haemolysis of washed erythrocytes, hydrolysis of human plasma albumin or globulin, and thrombin-like activity, but exhibited caseinolytic, alpha-fibrinogenolytic, and liver tissue haemorrhagic activities. Inhibition of coagulant and protease activities of RVBCMP by EDTA suggested a metalloprotease nature of this protein. RVBCMP showed antigenicity as was evident from the immunoblotting experiment. None of the tested plant extracts, except Leucus lavandulaefolia, inhibited the coagulant or haemorrhagic activity of RVBCMP. Interestingly, aqueous extracts of the tested plants as well as the commercial polyvalent antivenom raised against crude RVV differentially inhibited the coagulant and tissue haemorrhagic activity of RVBCMP. The current investigation provides a fairly good indication that RVBCMP possesses a distinct, perhaps overlapping, site for coagulant and tissue haemorrhagic activity.


Assuntos
Anticoagulantes/metabolismo , Coagulantes/metabolismo , Daboia/metabolismo , Metaloproteases/metabolismo , Venenos de Víboras/enzimologia , Sequência de Aminoácidos , Animais , Anticoagulantes/química , Coagulação Sanguínea/efeitos dos fármacos , Galinhas , Cromatografia em Gel , Coagulantes/química , Coagulantes/isolamento & purificação , Fibrinogênio/metabolismo , Humanos , Fígado , Metaloproteases/química , Metaloproteases/isolamento & purificação , Camundongos , Camundongos Endogâmicos BALB C , Extratos Vegetais/química , Folhas de Planta/química , Venenos de Víboras/química
13.
Environ Monit Assess ; 135(1-3): 107-17, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17505905

RESUMO

This study assesses the efficiency of various physico-chemical, biological and other tertiary methods for treating leachate. An evaluation study on the treatability of the leachate from methane phase bed (MPB) reactor indicated that at an optimum hydraulic retention time of 6 days, the efficiency of the reactor in terms of biological oxygen demand (BOD) and chemical oxygen demand (COD) removal was 91.29 and 82.69%, respectively. Recycling of the treated leachate through the municipal solid waste layers in the leachate recycling unit (LRU) resulted in a significant increase in the biodegradation of organics present in the leachate. Optimum BOD and COD removal efficiencies were achieved at the third recycle; additional recycling of the leachate did not produce any significant improvement. Physico-chemical treatment of the leachate demonstrated that alum and lime (Option 2) were more economical than coagulants lime and MgCO(3). A cost analysis of the economics of the various treatments revealed that the alternative treatment consisting of a MPB bed followed by a LRU and aerated lagoon is the most cost-effective treatment. However, the alternative consisting of a MPB followed by the LRU and a soil column, which is slightly more costly, would be the most appropriate treatment when adequate land is readily available.


Assuntos
Conservação dos Recursos Naturais , Eliminação de Resíduos , Saneamento , Eliminação de Resíduos Líquidos , Gerenciamento de Resíduos , Compostos de Alúmen/química , Anaerobiose , Biodegradação Ambiental , Compostos de Cálcio/química , Cidades , Coagulantes/química , Conservação dos Recursos Naturais/economia , Conservação dos Recursos Naturais/métodos , Monitoramento Ambiental , Filtração , Compostos de Magnésio/química , Metano/metabolismo , Óxidos/química , Oxigênio/química , Oxigênio/metabolismo , Eliminação de Resíduos/economia , Eliminação de Resíduos/métodos , Medição de Risco , Saneamento/economia , Saneamento/métodos , Eliminação de Resíduos Líquidos/economia , Eliminação de Resíduos Líquidos/métodos , Gerenciamento de Resíduos/economia , Gerenciamento de Resíduos/métodos
14.
Environ Technol ; 26(4): 389-95, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15906490

RESUMO

Herbal Pharmaceutical wastewater was subjected to physico-chemical treatment using conventional coagulants individually and in combination with different anionic, cationic and nonionic polyelectrolytes. Results indicate cationic polyelectrolyte to be the best polymer. Individually Alum did not give good results but Alum with cationic polymer in the ratio of 300:0.25 mg l(-1) resulted in the best removals of Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD) and Suspended Solids (SS) of 64.0%, 69.4% and 80.82% respectively. The next combination which resulted in good removals was Lime: cationic polymer in the ratio of 300:0.20 mg l(-1) with COD, BOD, and SS removals of 57.6%, 65.1% and 74.0%, respectively. Overall the studies indicated that the herbal pharmaceutical wastewater needs to be treated by physico-chemical treatment as a primary process to reduce the organic load and increase the performance efficiency of the secondary biological treatment process. This paper discusses in detail the studies carried out using conventional coagulants along with synthetic polyelectrolyte.


Assuntos
Eletrólitos , Resíduos Industriais , Compostos Orgânicos/isolamento & purificação , Eliminação de Resíduos Líquidos/métodos , Purificação da Água/métodos , Reatores Biológicos , Coagulantes/química , Eletrólitos/química , Preparações de Plantas
15.
Bioresour Technol ; 96(3): 303-7, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15474930

RESUMO

Natural polyelectrolytes are suitable coagulants for the treatment of industrial and minicipal wastewaters because they are safe and have environmental benefits. Chitosan, a natural cationic polyelectrolyte, and other similar coagulants were used in the treatment of an olive oil water suspension as a model for the processing wastewater. The effect of chitosan, starch, alum and ferric chloride on the coagulation of oil droplets were determined by the jar test apparatus and turbidometric measurements. Olive oil emulsion samples were prepared by the use of surface active agents and other agents that could form stable oil water emulsions. The effect of parameters such as pH, ionic strength and optimum dosage of the coagulants were determined in the jar test experiments. Following the jar experiments, with the optimum concentration of the suitable coagulant, the emulsions were placed in an induced air flotation (IAF) cell to separate the coagulated oil droplets from solution. In the air flotation experiments, the effect of temperature, surfactant concentration and air flowrate were determined on the decrease of turbidity and COD of the emulsion samples. In the jar experiments, chitosan and alum used together at concentrations of 15 and 25 ppm, respectively, at pH 6 produced the lowest turbidity values. In the air flotation experiments, a concentration of 100 ppm of chitosan, an air flowrate of 3 l/min, aeration time of 45 s, temperature of 20 degrees C and pH 6 produced optimum levels. At optimum conditions of coagulation and flotation stages, the COD of the olive oil emulsion could be reduced by 95%.


Assuntos
Ar , Quitosana/química , Coagulantes/química , Óleos de Plantas/química , Eliminação de Resíduos Líquidos/métodos , Compostos de Alúmen/química , Cloretos , Compostos Férricos/química , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Olea , Oxigênio/metabolismo , Amido/química
16.
Water Res ; 35(2): 405-10, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11228992

RESUMO

It is known that M. oleifera contains a natural coagulant in the seeds. In our previous research, the method using salt water to extract the active coagulation component from M. oleifera seeds was developed and compared with the conventional method using water. In this research, the active coagulation component was purified from a NaCl solution crude extract of Moringa oleifera seeds. The active component was isolated and purified from the crude extract through a sequence of steps that included salting-out by dialysis, removal of lipids and carbohydrates by homogenization with acetone, and anion exchange. Specific coagulation activity of the active material increased up to 34 times more than the crude extract after the ion exchange. The active component was not the same as that of water extract. The molecular weight was about 3000 Da. The Lowry method and the phenol-sulfuric acid method indicated that the active component was neither protein nor polysaccharide. The optimum pH of the purified active component for coagulation of turbidity was pH 8 and above. Different from the conventional water extracts, the active component can be used for waters with low turbidity without increase in the dissolved organic carbon concentration.


Assuntos
Coagulantes/isolamento & purificação , Rosales/química , Purificação da Água/métodos , Cromatografia por Troca Iônica , Coagulantes/química , Concentração de Íons de Hidrogênio , Nefelometria e Turbidimetria , Filipinas , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Sementes/química , Cloreto de Sódio/química , Soluções
17.
J Agric Food Chem ; 48(2): 451-6, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10691655

RESUMO

The chemical and microbial characteristics as well as the flavor and aroma of Los Pedroches cheese made using aqueous extracts of Cynara cardunculus L. flowers were compared with those of cheeses manufactured with extracts of Cynara humilis L. throughout ripening. The two thistle species assayed were found to have no appreciable effect on the moisture, fat, protein, and NaCl contents of the cheese or on its water activity, flavor, and aroma; however, the use of C. humilis resulted in reduced lactic acid content (p < 0.001) and higher pH values (p < 0.05) relative to those of cheese specimens produced with C. cardunculus. The protein breakdown of the cheeses was assessed in terms of soluble nitrogen (SN), nonprotein nitrogen (NPN), and amino acid nitrogen (AAN). Proteolysis was more marked and rapid in cheese containing C. cardunculus as coagulant, the SN and NPN contents of which were significantly higher (p < 0. 01) than those of the cheese obtained with the species C. humilis; AAN contents were similar in both species of Cynara throughout ripening. Although total viable, coliform, and lactobacilli counts were similar in cheeses produced with both types of plant coagulant throughout ripening, enterobacteria and yeasts counts (p < 0.01) and molds counts (p < 0.05) were higher in cheese produced with C. humilis than in cheese obtained with C. cardunculus.


Assuntos
Asteraceae/química , Queijo/análise , Coagulantes/química , Leite/química , Ovinos , Animais , Endopeptidases/isolamento & purificação , Análise de Alimentos , Manipulação de Alimentos/métodos , Extratos Vegetais/química
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