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1.
Trends Immunol ; 40(9): 799-808, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31401161

RESUMEN

Mammalian TPL-2 kinase (MAP3K8) mediates Toll-like receptor activation of ERK1/2 and p38α MAP kinases and is critical for regulating immune responses to pathogens. TPL-2 also has an important adaptor function, maintaining stability of associated ABIN-2 ubiquitin-binding protein. Consequently, phenotypes detected in Map3k8-/- mice can be caused by lack of TPL-2, ABIN-2, or both proteins. Recent studies show that increased inflammation of Map3k8-/- mice in allergic airway inflammation and colitis results from reduced ABIN-2 signaling, rather than blocked TPL-2 signaling. However, Map3k8-/- mice have been employed extensively to evaluate the potential of TPL-2 as an anti-inflammatory drug target. We posit that Map3k8D270A/D270A mice, expressing catalytically inactive TPL-2 and physiologic ABIN-2, should be used to evaluate the potential effects of TPL-2 inhibitors in disease.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/inmunología , Inflamación/inmunología , Quinasas Quinasa Quinasa PAM/inmunología , Proteínas Proto-Oncogénicas/inmunología , Transducción de Señal/inmunología , Animales , Humanos , Quinasas Quinasa Quinasa PAM/deficiencia , Ratones , Ratones Noqueados , Proteínas Proto-Oncogénicas/deficiencia
2.
Molecules ; 27(8)2022 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-35458744

RESUMEN

Microalgae have an outstanding capacity to efficiently produce value-added compounds. They have been inspiring researchers worldwide to develop a blue biorefinery, supporting the development of the bioeconomy, tackling the environmental crisis, and mitigating the depletion of natural resources. In this review, the characteristics of the carotenoids produced by microalgae are presented and the downstream processes developed to recover and purify them are analyzed, considering their main applications. The ongoing activities and initiatives taking place in Portugal regarding not only research, but also industrialization under the blue biorefinery concept are also discussed. The situation reported here shows that new techniques must be developed to make microalgae production more competitive. Downstream pigment purification technologies must be developed as they may have a considerable impact on the economic viability of the process. Government incentives are needed to encourage a constructive interaction between academics and businesses in order to develop a biorefinery that focuses on high-grade chemicals.


Asunto(s)
Microalgas , Biocombustibles , Biomasa , Carotenoides , Portugal
3.
Mar Drugs ; 19(8)2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34436305

RESUMEN

Biopolymers are very favorable materials produced by living organisms, with interesting properties such as biodegradability, renewability, and biocompatibility. Biopolymers have been recently considered to compete with fossil-based polymeric materials, which rase several environmental concerns. Biobased plastics are receiving growing interest for many applications including electronics, medical devices, food packaging, and energy. Biopolymers can be produced from biological sources such as plants, animals, agricultural wastes, and microbes. Studies suggest that microalgae and cyanobacteria are two of the promising sources of polyhydroxyalkanoates (PHAs), cellulose, carbohydrates (particularly starch), and proteins, as the major components of microalgae (and of certain cyanobacteria) for producing bioplastics. This review aims to summarize the potential of microalgal PHAs, polysaccharides, and proteins for bioplastic production. The findings of this review give insight into current knowledge and future direction in microalgal-based bioplastic production considering a circular economy approach. The current review is divided into three main topics, namely (i) the analysis of the main types and properties of bioplastic monomers, blends, and composites; (ii) the cultivation process to optimize the microalgae growth and accumulation of important biobased compounds to produce bioplastics; and (iii) a critical analysis of the future perspectives on the field.


Asunto(s)
Biopolímeros/química , Microalgas , Animales , Biodegradación Ambiental , Plásticos/química
4.
Molecules ; 26(21)2021 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-34771021

RESUMEN

Cholinium-based ionic liquids ([Ch]-based ILs) were investigated as electrolytes in the formation of aqueous biphasic systems (ABS) composed of polyethylene glycol (PEG) and sodium polyacrylate (NaPA) polymers. Both enhancement and decrease in the liquid-liquid demixing ability induced by electrolytes in PEG-NaPA aqueous biphasic systems were observed. It is shown that the ILs that most extensively partition to the PEG-rich phase tend to act as inorganic salts enhancing the two-phase formation ability, while those that display a more significant partition to the NaPA-rich phase decrease the ABS formation capacity. The gathered results allowed us to confirm the tailoring ability of ILs and to identify, for the first time, opposite effects induced by electrolytes on the PEG-NaPA ABS formation ability. The distribution of the electrolyte ions between the coexisting phases and the polyelectrolyte ion compartmentalization are key factors behind the formation of PEG-NaPA-based ABS.

5.
Molecules ; 26(22)2021 Nov 18.
Artículo en Inglés | MEDLINE | ID: mdl-34834050

RESUMEN

Bio-based ionic liquids (ILs) are being increasingly sought after, as they are more sustainable and eco-friendly. Purines are the most widely distributed, naturally occurring N-heterocycles, but their low water-solubility limits their application. In this work, four purines (theobromine, theophylline, xanthine, and uric acid) were combined with the cation tetrabutylammonium to synthesize bio-based ILs. The physico-chemical properties of the purine-based ILs were characterized, including their melting and decomposition temperatures and water-solubility. The ecotoxicity against the microalgae Raphidocelis subcapitata was also determined. The ILs show good thermal stability (>457 K) and an aqueous solubility enhancement ranging from 53- to 870-fold, in comparison to their respective purine percursors, unlocking new prospects for their application where aqueous solutions are demanded. The ecotoxicity of these ILs seems to be dominated by the cation, and it is similar to chloride-based IL, emphasizing that the use of natural anions does not necessarily translate to more benign ILs. The application of the novel ILs in the formation of aqueous biphasic systems (ABS), and as solubility enhancers, was also evaluated. The ILs were able to form ABS with sodium sulfate and tripotassium citrate salts. The development of thermoresponsive ABS, using sodium sulfate as a salting-out agent, was accomplished, with the ILs having different thermosensitivities. In addition, the purine-based ILs acted as solubility enhancers of ferulic acid in aqueous solution.


Asunto(s)
Líquidos Iónicos/síntesis química , Purinas/síntesis química , Líquidos Iónicos/química , Líquidos Iónicos/toxicidad , Microalgas/efectos de los fármacos , Purinas/química , Purinas/toxicidad , Compuestos de Amonio Cuaternario/síntesis química , Compuestos de Amonio Cuaternario/química , Compuestos de Amonio Cuaternario/toxicidad , Solubilidad , Temperatura
6.
Compr Rev Food Sci Food Saf ; 20(1): 787-818, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33325108

RESUMEN

This review will discuss, under the Circular Economy and Biorefinery concepts, the performance of the alternative solvents in the downstream process to recover natural pigments in a more sustainable way. Conventionally, pigments marketed on an industrial scale are produced through chemical synthesis by using petroleum derivatives as the main raw material. Also, the current production chain of the synthetic dyes is linear, with no solvent recycling and waste generation. Thus, the most promising processes of extraction and purification of natural pigments and strategies on the polishing of the solvents are here reviewed. In this review, the use of alternative solvents, namely, ionic liquids, eutectic solvents, aqueous solutions of surfactants, and edible oils, for recovering natural pigments was reviewed. Works discussing higher extraction yields and selectivity, while maintaining the stability of the target pigments, were reported. Also, a panorama between Sustainability and Circular Economy prospection was discussed for better comprehension of the main advances in the field. Behind the analysis of the works published so far on the theme, the most important lacunas to overcome in the next years on the field were pointed out and discussed. Also, the future trends and new perspectives to achieve the economic viability and sustainability of the processes using alternative solvents will be scrutinized.


Asunto(s)
Líquidos Iónicos , Fenómenos Químicos , Colorantes , Alimentos , Solventes
7.
Chemphyschem ; 20(5): 727-735, 2019 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-30672638

RESUMEN

Twelve surface-active ionic liquids (SAILs) and surface-active derivatives, based on imidazolium, ammonium, and phosphonium cations and containing one, or more, long alkyl chains in the cation and/or the anion, were synthetized and characterized. The aggregation behavior of these SAILs in water, as well as their adsorption at solution/air interface, were studied by assessing surface tension and conductivity. The CMC values obtained (0.03-6.0 mM) show a high propensity of these compounds to self-aggregate in aqueous media. Their thermal properties were also characterized, namely the melting point and decomposition temperature by using DSC and TGA, respectively. Furthermore, the toxicity of these SAILs was evaluated using the marine bacteria Aliivibrio fischeri (Gram-negative). According to the EC50 values obtained (0.3-2.7 mg L-1 ), the surface-active compounds tested should be considered "toxic" or "highly toxic". Their ability to induce cell disruption of Escherichia coli cells (also Gram-negative), releasing the intracellular green fluorescent protein (GFP) produced, was investigated. The results clearly evidence the capability of these SAILs to act as cell disruption agents.


Asunto(s)
Escherichia coli/química , Escherichia coli/efectos de los fármacos , Líquidos Iónicos/síntesis química , Líquidos Iónicos/farmacología , Compuestos de Amonio/química , Escherichia coli/citología , Proteínas Fluorescentes Verdes/biosíntesis , Proteínas Fluorescentes Verdes/química , Imidazoles/química , Líquidos Iónicos/química , Líquidos Iónicos/metabolismo , Compuestos Organofosforados/química , Propiedades de Superficie
8.
Chem Rev ; 117(10): 6984-7052, 2017 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-28151648

RESUMEN

Ionic liquids (ILs) have been proposed as promising media for the extraction and separation of bioactive compounds from the most diverse origins. This critical review offers a compilation on the main results achieved by the use of ionic-liquid-based processes in the extraction and separation/purification of a large range of bioactive compounds (including small organic extractable compounds from biomass, lipids, and other hydrophobic compounds, proteins, amino acids, nucleic acids, and pharmaceuticals). ILs have been studied as solvents, cosolvents, cosurfactants, electrolytes, and adjuvants, as well as used in the creation of IL-supported materials for separation purposes. The IL-based processes hitherto reported, such as IL-based solid-liquid extractions, IL-based liquid-liquid extractions, IL-modified materials, and IL-based crystallization approaches, are here reviewed and compared in terms of extraction and separation performance. The key accomplishments and future challenges to the field are discussed, with particular emphasis on the major lacunas found within the IL community dedicated to separation processes and by suggesting some steps to overcome the current limitations.


Asunto(s)
Productos Biológicos/química , Fraccionamiento Químico/métodos , Líquidos Iónicos/química , Preparaciones Farmacéuticas/química , Aminoácidos/química , Técnicas de Química Analítica , Lípidos/química , Extracción Líquido-Líquido/métodos , Ácidos Nucleicos/química , Proteínas/química
9.
Mar Drugs ; 17(5)2019 May 25.
Artículo en Inglés | MEDLINE | ID: mdl-31130603

RESUMEN

The replacement of synthetic compounds by natural products witnesses an increasing demand from the pharmaceutical, cosmetic, food and nutraceutical industries. Included in the set of natural raw materials that are poorly explored are the macroalgae. Despite the detailed characterization and identification of most relevant biomolecules that are present in the main macroalgae species, there remains a lack of efficient and economically viable processes available to meet the needs of the markets. In this work, an efficient and single-step process, based on aqueous solutions of Tween 20, to recover carotenoids from Sargassum muticum, an invasive brown macroalgae species present in the Portuguese coast, is proposed and optimized allowing an extraction yield of 2.78 ± 0.4 mgcarotenoids.gdried mass-1, which is shown to increase the extraction efficiency by 38% when compared with traditional methods.


Asunto(s)
Carotenoides/aislamiento & purificación , Técnicas de Química Analítica/métodos , Extractos Vegetales/aislamiento & purificación , Polisorbatos/química , Sargassum/química , Agua/química , Productos Biológicos/aislamiento & purificación
10.
Ecotoxicol Environ Saf ; 184: 109580, 2019 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-31493585

RESUMEN

Ionic Liquids (ILs) are generically regarded as environmentally "harmless" and thus, assumed as "non-toxic". However, due to the endless design possibilities, their ecotoxicological profile is still poorly known. An accurate knowledge on the toxicity of a substance is required, under the scope of environmental regulation worldwide, before their application and commercialization. Knowledge on the relationship between the chemical structure and toxic effects is essential for the future design of more biocompatible solvents. Focusing on the use of ILs as base lubricants, lubricant additives, or even as potential working fluids for absorption heat pumps, the knowledge on its environmental impact is of great importance, due to the possibility of spills. In this specific context, four analogues of glycine-betaine-based ILs (AGB-ILs) and four glycine-betaine based ILs (GB-ILs) were synthesized and characterized. Their ecotoxicity was assessed using representatives of two trophic levels in aquatic ecosystems, the bacteria Allivibrio fischeri (commonly used as a screening test organism) and the microalgae Raphidocelis subcapitata (as an alternative test organism that has been proven very sensitive to several IL families). The microalgae were more sensitive than the bacteria, hence, following a precautionary principle, we recommend considering the toxicity towards microalgae as an indicator in future studies regarding the focused ILs. Although four of the studied ILs were derived from a natural amino acid, all were considered hazardous for the aquatic environment, disproving the primary theory that all ILs derived from natural compounds are benign. Furthermore, the modification in the structure of anion and the cation can lead to the increase of toxicity.


Asunto(s)
Betaína/química , Glicina/química , Líquidos Iónicos/toxicidad , Contaminantes Químicos del Agua/toxicidad , Aliivibrio fischeri/efectos de los fármacos , Aniones/química , Cationes/química , Chlorophyceae/efectos de los fármacos , Ecotoxicología , Biomarcadores Ambientales/efectos de los fármacos , Líquidos Iónicos/síntesis química , Líquidos Iónicos/química , Contaminantes Químicos del Agua/síntesis química , Contaminantes Químicos del Agua/química
11.
Phys Chem Chem Phys ; 20(47): 29764-29777, 2018 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-30462106

RESUMEN

Cell membrane models have been used to evaluate the interactions of various imidazolium-based ionic liquids (ILs) with Langmuir monolayers of two types of phospholipids and cholesterol. Data from surface pressure isotherms, Brewster angle microscopy (BAM) and polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) pointed to significant effects on the monolayers of 1,2-dipalmitoyl-sn-glycero-3-phosphocholine (DPPC) and cholesterol, used to mimic the membranes of eukaryotic cells, for ILs containing more than 6 carbon atoms in the alkyl chain (i.e. n > 6). For ILs with less hydrophobic tails (n ≤ 6) and low concentrations, the effects were almost negligible, therefore, such ILs should not be toxic to eukaryotic cells. The hydrophobicity of the anion was also proved to be relevant, with larger impact from ILs containing tetrafluoroborate ([BF4]-) than chloride (Cl-). Molecular dynamics simulations for DPPC monolayers at the surface of aqueous solutions of alkylimidazolium chloride ([Cnmim]Cl) confirm the penetration of the IL cations with longer alkyl chains into the phospholid monolayer and provide information on their location and orientation within the monolayer. For monolayers of dipalmitoylphosphatidyl glycerol (DPPG), which is negatively charged like bacteria cell membranes, the ILs induced much larger effects. Similarly to the results for DPPC and cholesterol, effects increased with the number of carbon atoms in the alkyl chain and with a more hydrophobic anion [BF4]-. Overall, the approach used can provide relevant information of molecular-level interactions behind the toxicity mechanisms and support the design of (quantitative) structure-activity relationship models, which may help design more efficient and environmentally friendly ILs.


Asunto(s)
Membrana Celular/química , Imidazoles/química , Líquidos Iónicos/química , Modelos Biológicos , Células Eucariotas/química , Interacciones Hidrofóbicas e Hidrofílicas , Simulación de Dinámica Molecular
12.
J Chem Phys ; 148(19)2018 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-30283158

RESUMEN

This work provides a comprehensive evaluation of the effect of the cation alkyl side chain length of the 1-alkyl-3-methylimidazolium chloride series ([C n C1im]Cl, n = 2-14) of ionic liquids (ILs) on their capability to form aqueous biphasic systems (ABSs) with salts and self-aggregation derived properties. The liquid-liquid phase behavior of ternary systems composed of [C n C1im]Cl, water, and K3PO4 or K2CO3 and the respective Setschenow salting-out coefficients (ks ), a quantitative measure of the two-phase formation ability, were determined. An odd-even effect in the ks values along the number of methylene groups of the longest IL cation alkyl side chain was identified for the ABS formed by K2CO3, a weaker salting-out agent where the phenomenon is clearly identified. In general, cations with even alkyl side chains, being likely to display higher molar volumes, are more easily salted-out and thus more prone to undergo phase separation. The odd-even effect in the ks values is, however, more significant in ILs up to n = 6, where the nanostructuration/nanosegregation of ILs plays a less relevant role. Still, with the [C n C1im]Cl (n = 7-14) series of ILs, an odd-even effect was also identified in the ILs' ionization degree, molar conductivity, and conductivity at infinite dilution. In summary, it is shown here that the ILs' odd-even effect occurs in IL aqueous solutions and not just in neat ILs, an already well-established phenomenon occurring in a series of ILs' properties described as a result of the orientation of the terminal methyl groups to the imidazolium ring cation and consequent effect in the ILs' cohesive energy.

13.
Ecotoxicol Environ Saf ; 165: 597-602, 2018 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-30236922

RESUMEN

The design of environmentally friendlier solvents has gained increasing relevance in the last decade. Deep eutectic solvents (DES) have recently emerged, with advantages like low-cost and putative lower environmental impact. However, information about DES toxicity is still scarce. This work aims to contribute to profiling the ecotoxicity of DES based on cholinium chloride ([Chol]Cl). Six DES were addressed, combining [Chol]Cl (as hydrogen bond acceptor - HBA) with ethylene glycol, glycerol, 1,2-propanediol, propionic acid, 1-propanol, and urea as hydrogen bond donors (HBD), in different molar ratios. The Microtox® Acute Toxicity Test, was used for assessing their toxicity towards the marine bacteria Allivibrio fischeri . Because the dissociation of DES in water is expected, analysis appraising the mixtures toxicity theory should be considered, which is a step forward in this field. This analysis suggested that [Chol]Cl and all HBD with the exception of propionic acid:[Chol]Cl 1:2 and 4:1 behave antagonistically, which is contrary to what has been suggested previously. The most extreme cases are Urea:[Chol]Cl and 1-Propanol:[Chol]Cl, with EC50 values higher than their starting materials dosed singly, configuring very promising and biocompatible alternative solvents. Toxicity was found to be dependent on DES composition, as well as on molar proportions of the starting materials.


Asunto(s)
Contaminantes Ambientales/química , Solventes/química , Bacterias/efectos de los fármacos , Ambiente , Contaminantes Ambientales/toxicidad , Análisis de Regresión , Solventes/toxicidad , Pruebas de Toxicidad Aguda
14.
Ecotoxicol Environ Saf ; 143: 315-321, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28570952

RESUMEN

Although magnetic ionic liquids (MILs) are not yet industrially applied, their continued development and eventual commercial use may lead to their appearance into the aquatic ecosystem through accidental spills or effluents, consequently promoting aquatic contaminations. Furthermore, the deficient information and uncertainty surrounding the environmental impact of MILs could be a major barrier to their widespread industrial application and international registration. Thus, in the present work, a range of cholinium salt derivatives with magnetic properties was synthesized and their ecotoxicity was evaluated towards the luminescent bacteria Vibrio fischeri. The results suggest that all MILs structures tested are moderately toxic, or even toxic, to the bacteria. Furthermore, their toxicity is highly dependent on the structural modifications of the cation, namely the alkyl side chain length and the number of hydroxyethyl groups, as well as the atomic number of the metal anion. Finally, from the magnetic anions evaluated, the [MnCl4]2- is the less toxic. In order to improve the knowledge for the prospective design of environmentally safer MILs, it is important to expand this study to other aquatic organisms at different trophic levels.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Organismos Acuáticos/efectos de los fármacos , Ecotoxicología , Líquidos Iónicos/toxicidad , Magnetismo , Contaminantes Químicos del Agua/toxicidad , Aniones , Cationes , Líquidos Iónicos/química , Contaminantes Químicos del Agua/química
15.
J Chem Technol Biotechnol ; 92(9): 2287-2299, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30270960

RESUMEN

A series of new self-buffering ionic liquids (ILs) based on Good's buffers (GBs) anions and the tetrabutylphosphonium cation ([P4444]+) was here synthesized and characterized. The self-buffering behaviour of the GB-ILs was confirmed by measuring their protonation constants by potentiometry. Further, their ability to form aqueous biphasic systems with the biodegradable potassium citrate salt was evaluated, and further investigated for the extraction of proteins, using bovine serum albumin (BSA) as a model protein. If these ionic structures display self-buffering characteristics as well as a low toxicity towards the luminescent bacteria Vibrio fischeri, they were additionally found to be highly effective in the formation of ABS and in the extraction of BSA - extraction efficiencies of 100% to the IL-rich phase obtained in a single-step. The BSA secondary structure in the aqueous IL-rich solutions was evaluated through infrared spectroscopic studies revealing the protein-friendly nature of the synthesized ILs. Dynamic light scattering (DLS), "COnductor-like Screening MOdel for Real Solvents" (COSMO-RS), and molecular docking studies were finally carried out to better understand the main driving forces of the extraction process. The results suggest that van der Waals and hydrogen-bonding interactions are important driving forces of the protein migration towards the GB-IL-rich phase, while the molecular docking investigations demonstrated a stabilizing effect of the studied ILs over the protein.

16.
Rev Gastroenterol Peru ; 36(2): 135-42, 2016.
Artículo en Español | MEDLINE | ID: mdl-27409090

RESUMEN

OBJECTIVE: To describe the clinical and endoscopic features of caustics injuries in the upper gastrointestinal tract in patients of the National Hospital Daniel Alcides Carrión. MATERIALS AND METHODS: A descriptive study was conducted; the study populations were patients diagnosed with caustic ingestion who were admitted into the Gastroenterology service of the HNDAC to perform an upper endoscopy during the period of January 2009 to December 2012. We documented the type of caustic substance ingested, cause of intake, amount ingested, intake mode, signs or symptoms present, endoscopic findings as classified by Zargar, presence of complications and treatment performed. Analysis was performed comparing them based on the ingested caustic type: acid or alkali. RESULTS: We obtained 91 patients; the average age was 30.6±16.3 years. Caustic substances ingested were: bleach (sodium hypochlorite) in 71 (78%) patients, muriatic acid (hydrochloric acid) in 18 (20%) patients, caustic soda in 2 (2%) patients. The average intake was 136ml (30-500 ml). The most frequent signs and symptoms were vomiting, abdominal pain, nausea and sore throat. The 46% of patients had injuries. 100% of patients who ingested acid and 33% who ingested alkali had lesions. Five (5%) patients had oropharyngeal lesions, 24 (26%) in the esophagus, 36 (40%) in the stomach and 12 (13%) in the duodenum. Grade I lesions were found in 10 (11%) patients, 16 (18%) patients with grade II lesions and 15 (16%) of patients with grade III, 12 patients who toke acid had lesions of grade III. Esophageal stricture was found in 2 (2%) patients, gastric stenosis in 7 (8%) patients and esophageal and gastric stenosis in 3 (3%) patients. Two patients required pneumatic dilation and 10 surgical treatments. CONCLUSION: Most injuries were found in the stomach. Acidic injuries occur more frequently and with greater severity than alkaline. Acidic substances produce esophageal or gastric stenosis more frequently than alkaline.


Asunto(s)
Quemaduras Químicas/diagnóstico , Cáusticos/toxicidad , Orofaringe/lesiones , Tracto Gastrointestinal Superior/lesiones , Adolescente , Adulto , Anciano , Quemaduras Químicas/etiología , Quemaduras Químicas/terapia , Endoscopía del Sistema Digestivo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Orofaringe/diagnóstico por imagen , Tracto Gastrointestinal Superior/diagnóstico por imagen , Adulto Joven
17.
Chemistry ; 21(12): 4781-8, 2015 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-25652351

RESUMEN

Antibodies obtained from egg yolk of immunized hens, immunoglobulin Y (IgY), are an alternative to the most focused mammal antibodies, because they can be obtained in higher titers by less invasive approaches. However, the production cost of high-quality IgY for large-scale applications remains higher than that of other drug therapies due to the lack of efficient purification methods. The search for new purification platforms is thus vital. The solution could be liquid-liquid extraction by using aqueous biphasic systems (ABS). Herein, we report the extraction and attempted purification of IgY from chicken egg yolk by using a new ABS composed of polymers and Good's buffer ionic liquids (GB-ILs). New self-buffering and biocompatible ILs based on the cholinium cation and anions derived from Good's buffers were synthesized and the self-buffering characteristics and toxicity were characterized. Moreover, when these GB-ILs are combined with PPG 400 (poly(propylene) glycol with a molecular weight of 400 g mol(-1)) to form ABS, extraction efficiencies, of the water-soluble fraction of proteins, ranging between 79 and 94% were achieved in a single step. Based on computational investigations, we also demonstrate that the preferential partitioning of IgY for the GB-IL-rich phase is dominated by hydrogen-bonding and van der Waals interactions.


Asunto(s)
Líquidos Iónicos/química , Animales , Sitios de Unión , Pollos , Yema de Huevo/metabolismo , Inmunoglobulinas/aislamiento & purificación , Líquidos Iónicos/metabolismo , Extracción Líquido-Líquido , Simulación del Acoplamiento Molecular , Polietilenglicoles/química , Unión Proteica , Estructura Terciaria de Proteína
18.
Phys Chem Chem Phys ; 16(37): 19952-63, 2014 Oct 07.
Artículo en Inglés | MEDLINE | ID: mdl-25119425

RESUMEN

The design of ionic liquids has been focused on the cation-anion combinations but other more subtle approaches can be used. In this work the effect of the branching of the cation alkyl chain on the design of ionic liquids (ILs) is evaluated. The mutual solubilities with water and toxicities of a series of bis(trifluoromethylsulfonyl)-based ILs, combined with imidazolium, pyridinium, pyrrolidinium, and piperidinium cations with linear or branched alkyl chains, are reported. The mutual solubility measurements were carried out in the temperature range from (288.15 to 323.15) K. From the obtained experimental data, the thermodynamic properties of the solution (in the water-rich phase) were determined and discussed. The COnductor like Screening MOdel for Real Solvents (COSMO-RS) was used to predict the liquid-liquid equilibrium. Furthermore, molecular dynamic simulations were also carried out aiming to get a deeper understanding of these fluids at the molecular level. The results show that the increase in the number of atoms at the cation ring (from five to six) leads to a decrease in the mutual solubilities with water while increasing their toxicity, and as expected from the well-established relationship between toxicities and hydrophobicities of ILs. The branching of the alkyl chain was observed to decrease the water solubility in ILs, while increasing the ILs solubility in water. The inability of COSMO-RS to correctly predict the effect of branching alkyl chains toward water solubility on them was confirmed using molecular dynamic simulations to be due to the formation of nano-segregated structures of the ILs that are not taken into account by the COSMO-RS model. In addition, the impact of branched alkyl chains on the toxicity is shown to be not trivial and to depend on the aromatic nature of the ILs.


Asunto(s)
Líquidos Iónicos/química , Agua/química , Aliivibrio fischeri/efectos de los fármacos , Cationes/química , Interacciones Hidrofóbicas e Hidrofílicas , Imidazoles/química , Líquidos Iónicos/toxicidad , Simulación de Dinámica Molecular , Piperidinas/química , Piridinas/química , Pirrolidinas/química , Solubilidad , Temperatura , Termodinámica
19.
J Chem Phys ; 140(6): 064505, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24527930

RESUMEN

The influence of the cation's central atom in the behavior of pairs of ammonium- and phosphonium-based ionic liquids was investigated through the measurement of densities, viscosities, melting temperatures, activity coefficients at infinite dilution, refractive indices, and toxicity against Vibrio fischeri. All the properties investigated are affected by the cation's central atom nature, with ammonium-based ionic liquids presenting higher densities, viscosities, melting temperatures, and enthalpies. Activity coefficients at infinite dilution show the ammonium-based ionic liquids to present slightly higher infinite dilution activity coefficients for non-polar solvents, becoming slightly lower for polar solvents, suggesting that the ammonium-based ionic liquids present somewhat higher polarities. In good agreement these compounds present lower toxicities than the phosphonium congeners. To explain this behavior quantum chemical gas phase DFT calculations were performed on isolated ion pairs at the BP-TZVP level of theory. Electronic density results were used to derive electrostatic potentials of the identified minimum conformers. Electrostatic potential-derived CHelpG and Natural Population Analysis charges show the P atom of the tetraalkylphosphonium-based ionic liquids cation to be more positively charged than the N atom in the tetraalkylammonium-based analogous IL cation, and a noticeable charge delocalization occurring in the tetraalkylammonium cation, when compared with the respective phosphonium congener. It is argued that this charge delocalization is responsible for the enhanced polarity observed on the ammonium based ionic liquids explaining the changes in the thermophysical properties observed.


Asunto(s)
Compuestos de Amonio/química , Líquidos Iónicos/química , Compuestos Organofosforados/química , Aliivibrio fischeri/efectos de los fármacos , Aliivibrio fischeri/fisiología , Compuestos de Amonio/toxicidad , Cationes/química , Cationes/toxicidad , Líquidos Iónicos/toxicidad , Compuestos Organofosforados/toxicidad , Refractometría , Viscosidad
20.
Ecotoxicol Environ Saf ; 102: 48-54, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24580821

RESUMEN

Cholinium-based ionic liquids are quaternary ammonium salts with a wide range of potential industrial applications. Based on the fact that the cholinium is a complex B vitamin and widely used as food additive, the cholinium-based ionic liquids are generically regarded as environmentally "harmless" and thus, accepted as "non-toxic", although their ecotoxicological profile is poorly known. This work provides new ecotoxicological data for ten cholinium-based salts and ionic liquids, aiming to extend the surprisingly restricted body of knowledge about the ecotoxicity of this particular family and to gain insight on the toxicity mechanism of these compounds. The results reported here show that not all the cholinium tested can be considered harmless towards the test organism adopted. Moreover, the results suggest that the cholinium family exhibits a different mechanism of toxicity as compared to the imidazolium ionic liquids previously described in the literature.


Asunto(s)
Aliivibrio fischeri/efectos de los fármacos , Organismos Acuáticos/efectos de los fármacos , Líquidos Iónicos/toxicidad , Compuestos de Amonio Cuaternario/toxicidad , Contaminantes Químicos del Agua/toxicidad , Ecotoxicología , Concentración 50 Inhibidora
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