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1.
Chem Commun (Camb) ; 57(17): 2156-2159, 2021 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-33523051

RESUMEN

This work reports, for the first time, an Ethanolic Two-Phase System (ETPS) based on polypropylene glycol 2000 (PPG 2000), mono-, di-, tri-ethylene glycol, and ethanol. An ionic liquid (IL) (1-butyl-3-methylpyridinium chloride) was used as an adjuvant. This ETPS shows promising results for the extraction of highly hydrophobic compounds. Bixin (model of hydrophobic compounds) migrates completely to the PPG 2000-rich phase, while ascorbic acid (hydrophilic compound) migrated to the opposite phase.

2.
Biotechnol Rep (Amst) ; 25: e00411, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32211306

RESUMEN

This study evaluated simultaneously the raw vinasse degradation, an effluent from the sugar-alcohol industry, the laccase production by Pleurotus sajor-caju and its purification using aqueous two-phase systems (ATPS). To improve laccase production, different concentrations of inducers (ethanol and CuSO4) were added. The higher laccase production promoted an increase of 4-fold using 0.4 mM of CuSO4 as inducer, with maximum enzymatic activity of 539.3 U/L on the 3rd day of fermentation. The final treated vinasse had a decolorization of 92% and turbidity removal of 99% using CuSO4. Moreover, the produced laccase was then purified by ATPS in a single purification step, reaching 2.9-fold and recovered ≈ 99,9 %, in the top phase (PEG-rich phase) using 12 wt% of PEG 1500 + 20 wt% of citrate buffer + enzyme broth + water, at 25 °C. Thus, an integrated process of vinasse degradation, laccase production and purification with potential industrial application was proposed.

3.
Appl Biochem Biotechnol ; 150(1): 25-32, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18427738

RESUMEN

Amylases and lipases are highly demanded industrial enzymes in various sectors such as food, pharmaceuticals, textiles, and detergents. Amylases are of ubiquitous occurrence and hold the maximum market share of enzyme sales. Lipases are the most versatile biocatalyst and bring about a range of bioconversion reactions such as hydrolysis, inter-esterification, esterification, alcoholysis, acidolysis, and aminolysis. The objective of this work was to study the feasibility for amylolitic and lipolytic production using a bacterium strain isolated from petroleum contaminated soil in the same submerged fermentation. This was a sequential process based on starch and vegetable oils feedstocks. Run were performed in batchwise using 2% starch supplemented with suitable nutrients and different vegetable oils as a lipase inducers. Fermentation conditions were pH 5.0; 30 degrees C, and stirred speed (200 rpm). Maxima activities for amyloglucosidase and lipase were, respectively, 0.18 and 1,150 U/ml. These results showed a promising methodology to obtain both enzymes using industrial waste resources containing vegetable oils.


Asunto(s)
Bacterias/aislamiento & purificación , Petróleo/toxicidad , Microbiología del Suelo , Amilasas/biosíntesis , Bacterias/efectos de los fármacos , Bacterias/enzimología , Bacterias/genética , Contaminación Ambiental , Lipasa/biosíntesis , Contaminantes del Suelo/toxicidad
4.
Data Brief ; 20: 2045-2053, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30310829

RESUMEN

This paper contains data related to the research paper entitled "Organic two-phase system based on acetonitrile + water + polyvinylpyrrolidone, a novel concept of liquid-liquid equilibrium: phase diagrams and phenolic compounds partitioning". Data of phase equilibrium were obtained using the cloud point method. After this step, some blending points were chosen to perform the phenolic compounds partitioning (gallic acid, quercetin dihydrate and cyanidin 3-O-glucoside chloride).

5.
Enzyme Microb Technol ; 52(3): 141-50, 2013 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-23410924

RESUMEN

Ionic liquids (ILs) have evolved as a new type of non-aqueous solvents for biocatalysis, mainly due to their unique and tunable physical properties. A number of recent review papers have described a variety of enzymatic reactions conducted in IL solutions, on the other hand, to improve the enzyme's activity and stability in ILs; major methods being explored include the enzyme immobilization (on solid support, sol-gel, etc.), protic ionic liquids used as an additive process. The immobilization of the lipase from Burkholderia cepacia by the sol-gel technique using protic ionic liquids (PIL) as additives to protect against inactivation of the lipase due to release of alcohol and shrinkage of the gel during the sol-gel process was investigated in this study. The influence of various factors such as the length of the alkyl chain of protic ionic liquids (monoethanolamine-based) and a concentration range between 0.5 and 3.0% (w/v) were evaluated. The resulting hydrophobic matrices and immobilized lipases were characterised with regard to specific surface area, adsorption-desorption isotherms, pore volume (V(p)) and size (d(p)) according to nitrogen adsorption and scanning electron microscopy (SEM), physico-chemical properties (thermogravimetric - TG, differential scanning calorimetry - DSC and Fourier transform infrared spectroscopy - FTIR) and the potential for ethyl ester and emulsifier production. The total activity yields (Y(a)) for matrices of immobilized lipase employing protic ionic liquids as additives always resulted in higher values compared with the sample absent the protic ionic liquids, which represents 35-fold increase in recovery of enzymatic activity using the more hydrophobic protic ionic liquids. Compared with arrays of the immobilized biocatalyst without additive, in general, the immobilized biocatalyst in the presence of protic ionic liquids showed increased values of surface area (143-245 m(2) g(-1)) and pore size (19-38 Å). Immobilization with protic ionic liquids also favoured reduced mass loss according to TG curves (always less than 42.9%) when compared to the immobilized matrix without protic ionic liquids (45.1%), except for the sample containing 3.0% protic ionic liquids (46.5%), verified by thermogravimetric analysis. Ionic liquids containing a more hydrophobic alkyl group in the cationic moiety were beneficial for recovery of the activity of the immobilized lipase. The physico-chemical characterization confirmed the presence of the enzyme and its immobilized derivatives obtained in this study by identifying the presence of amino groups, and profiling enthalpy changes of mass loss.


Asunto(s)
Proteínas Bacterianas/metabolismo , Enzimas Inmovilizadas/metabolismo , Líquidos Iónicos/química , Lipasa/metabolismo , 2-Propanol/metabolismo , Proteínas Bacterianas/química , Burkholderia cepacia/enzimología , Rastreo Diferencial de Calorimetría , Emulsionantes/metabolismo , Enzimas Inmovilizadas/química , Esterificación , Geles , Hidrólisis , Interacciones Hidrofóbicas e Hidrofílicas , Ácidos Láuricos/metabolismo , Lipasa/química , Microscopía Electrónica de Rastreo , Aceite de Oliva , Aceites de Plantas/metabolismo , Porosidad , Gel de Sílice , Aceite de Soja/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Termogravimetría
6.
Appl Biochem Biotechnol ; 161(1-8): 288-300, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20119857

RESUMEN

The hydrolysis of triglycerides at the oil-water interface, synthesis of esters and transesterification in microaqueous conditions are catalysed by lipase. For its application, a proper purification method was necessary. This study examined the application of an aqueous two-phase system to partition porcine pancreatic lipase. The influence of molecular weight and concentration of polyethylene glycol (PEG), tie line length (TLL), potassium phosphate concentration, sodium chloride (NaCl) addition and temperature in the partition was studied. The enzyme was more efficiently purified in PEG 8,000 at 14.5 degrees C (PF = 3.89-fold), presenting more recoveries at the top phase with shorter TLL and lower concentrations of PEG and potassium phosphate. Moreover, the increase of these variables repressed the purification and the further addition of NaCl did not promote the purification of the enzyme. These results demonstrated the efficiency of the aqueous two-phase system on lipase purification.


Asunto(s)
Lipasa/aislamiento & purificación , Páncreas/enzimología , Fosfatos/química , Polietilenglicoles/química , Compuestos de Potasio/química , Animales , Lipasa/química , Cloruro de Sodio/química , Solubilidad , Solventes/química , Porcinos , Temperatura , Agua/química
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