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1.
Food Chem (Oxf) ; 4: 100068, 2022 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-35415675

RESUMEN

The effect of abiotic factors, such as weather and climate can alter the properties of vegetable oils. In this work, the effects of the refining process and pre-drying of Moringa oleifera Lam. seeds collected in the dry and rainy seasons (seasonality) were evaluated on the characteristics of the extracted oils. The refined and crude dry season oils had lower acidity and moisture content than the dry and raw rainy season oils. Oleic acid (C18:1) showed the highest concentration in the different Moringa oils studied. The results suggest that dry season oils are more suitable for application as feedstocks in the cosmetic, food, medicinal and pharmaceutical industries. Furthermore, refining proved to be efficient in removing free fatty acids and in lightening the oil.

2.
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.

3.
Biochimie ; 178: 96-104, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32941939

RESUMEN

Caatinga is a Brazilian semi-arid ecosystem that stands out for presenting unique environmental characteristics with a dry, spiny and deciduous shrub/forest vegetation with several species that can be renewable oil sources with potential applicability in oleochemical and nutrition. Caatinga oilseeds have a high content of unsaturated fatty acids, phytosterols and sterols, and this composition is related to its nutritional potential. The present review summarizes the knowledge on the oil contents and fatty acid profiles of seeds from six representatives caatinga species. It was observed that plants species like Caju (Anacardium occidentale L.), Favela (Cnidoscolus quercifolius Pohl), Licuri (Syagrus coronata (Mart.) Becc.), Pinhão-bravo (Jatropha mollissima Pohl Baill), Pequi (Caryocar brasiliense Camb) and Oiticica (Licania rígida Benth) contains approximately 33.1, 33.5, 49.2, 18.3, 70.16 and 57.0% w/w of oil, respectively, on a dry weight basis. Their fatty acid profiles are mostly saturated for Licuri oil, with a high content of lauric acid (up to 40%) and unsaturated for Favela, Pinhão-bravo, Cashew nut, Pequi and Oiticica oils. Oiticica oil shows a high concentration of unusual conjugated polyunsaturated fatty acids, like α-Eleostearic and Licanic acid with 16.90 and 43.20% w/w, respectively.


Asunto(s)
Ácidos Grasos/análisis , Ácidos Grasos/química , Aceites de Plantas/análisis , Aceites de Plantas/química , Brasil , Ácidos Grasos/uso terapéutico , Frutas/química , Nueces/química , Aceites de Plantas/uso terapéutico , Semillas/química , Desarrollo Sostenible
4.
Molecules ; 25(16)2020 Aug 12.
Artículo en Inglés | MEDLINE | ID: mdl-32806564

RESUMEN

In the present work the radish (Raphanus sativus L.) was used as the low-cost alternative source of peroxidase. The enzyme was immobilized in different supports: coconut fiber (CF), calcium alginate microspheres (CAMs) and silica SBA-15/albumin hybrid (HB). Physical adsorption (PA) and covalent binding (CB) as immobilization techniques were evaluated. Immobilized biocatalysts (IBs) obtained were physicochemical and morphologically characterized by SEM, FTIR and TGA. Also, optimum pH/temperature and operational stability were determined. For all supports, the immobilization by covalent binding provided the higher immobilization efficiencies-immobilization yield (IY%) of 89.99 ± 0.38% and 77.74 ± 0.42% for HB and CF, respectively. For CAMs the activity recovery (AR) was of 11.83 ± 0.68%. All IBs showed optimum pH at 6.0. Regarding optimum temperature of the biocatalysts, HB-CB and CAM-CB maintained the original optimum temperature of the free enzyme (40 °C). HB-CB showed higher operational stability, maintaining around 65% of the initial activity after four consecutive cycles. SEM, FTIR and TGA results suggest the enzyme presence on the IBs. Radish peroxidase immobilized on HB support by covalent binding is promising in future biotechnological applications.


Asunto(s)
Enzimas Inmovilizadas/química , Peroxidasa/química , Proteínas de Plantas/química , Raphanus/enzimología , Estabilidad de Enzimas
5.
Biomolecules ; 10(5)2020 05 06.
Artículo en Inglés | MEDLINE | ID: mdl-32384801

RESUMEN

Brazilian red propolis has been proposed as a new source of compounds with cytotoxic activity. Red propolis is a resinous material of vegetal origin, synthesized from the bees of the Appis mellifera family, with recognized biological properties. To obtain actives of low polarity and high cytotoxic profile from red propolis, in this work, we proposed a new solvent accelerated extraction method. A complete 23 factorial design was carried out to evaluate the influence of the independent variables or factors (e.g., temperature, number of cycles, and extraction time) on the dependent variable or response (i.e., yield of production). The extracts were analyzed by gas chromatography coupled with mass spectrometry for the identification of chemical compounds. Gas chromatography analysis revealed the presence of hydrocarbons, alcohols, ketones, ethers, and terpenes, such as lupeol, lupenone, and lupeol acetate, in most of the obtained extracts. To evaluate the cytotoxicity profile of the obtained bioactives, the 3-(4,5-dimethyl-2-thiazole)-2,5-diphenyl-2-H-tetrazolium bromide colorimetric assay was performed in different tumor cell lines (HCT116 and PC3). The results show that the extract obtained from 70 °C and one cycle of extraction of 10 min exhibited the highest cytotoxic activity against the tested cell lines. The highest yield, however, did not indicate the highest cytotoxic activity, but the optimal extraction conditions were indeed dependent on the temperature (i.e., 70 °C).


Asunto(s)
Antineoplásicos/química , Própolis/química , Alcoholes/análisis , Antineoplásicos/toxicidad , Línea Celular Tumoral , Éteres/análisis , Humanos , Cetonas/análisis , Própolis/toxicidad , Terpenos/análisis
6.
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).

7.
Bioprocess Biosyst Eng ; 38(4): 721-8, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25344826

RESUMEN

A novel strategy for the production of lipase by Bacillus sp. ITP-001 in a stirred tank fermenter using perfluorodecalin (PFD) was studied. Firstly, a response surface methodology 2(2) with three central points was employed to optimise the effect of agitation speed and aeration rate in lipase production. According to the response from the experimental designs, 300 rpm (revolutions per minute) and 0.5 vvm (air volume/liquid volume per minute) were found to provide the best condition (lipolytic activity: LA = 3,140.76 U mL(-1)). Then, the influence of PFD concentration on the fermentation process was evaluated. Incorporation of PFD at all concentrations above 1% had no statistically significant influence on lipase production, that is, the previous optimisation allowed the reduction of the amount of PFD added besides increasing lipase production. Furthermore, PFD could be used in three sequential fermentations without altering the statistical production of lipase, reducing by 67% the cost of PFD addition.


Asunto(s)
Bacillus/metabolismo , Fluorocarburos/química , Microbiología Industrial , Lipasa/biosíntesis , Oxígeno/química , Biomasa , Reactores Biológicos , Fermentación , Concentración de Iones de Hidrógeno , Temperatura
8.
Bioprocess Biosyst Eng ; 37(9): 1781-8, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24556978

RESUMEN

Lipase from Aspergillus niger was obtained from the solid-state fermentation of a novel agroindustrial residue, pumpkin seed flour. The partially purified enzyme was encapsulated in a sol-gel matrix, resulting in an immobilization yield of 71.4 %. The optimum pH levels of the free and encapsulated enzymes were 4.0 and 3.0, respectively. The encapsulated enzyme showed greater thermal stability at temperatures of 45 and 60 °C than the free enzyme. The positive influence of the encapsulation process was observed on the thermal stability of the enzyme, since a longer half-life t 1/2 and lower deactivation constant were obtained with the encapsulated lipase when compared with the free lipase. Kinetic parameters were found to follow the Michaelis-Menten equation. The K m values indicated that the encapsulation process reduced enzyme-substrate affinity and the V max was about 31.3 % lower than that obtained with the free lipase. The operational stability was investigated, showing 50 % relative activity up to six cycles of reuse at pH 3.0 at 37 °C. Nevertheless, the production of lipase from agroindustrial residue associated with an efficient immobilization method, which promotes good catalytic properties of the enzyme, makes the process economically viable for future industrial applications.


Asunto(s)
Aspergillus niger/enzimología , Cucurbita/metabolismo , Geles , Lipasa/metabolismo , Estabilidad de Enzimas , Fermentación , Concentración de Iones de Hidrógeno , Cinética , Temperatura
9.
Sep Purif Technol ; 136: 74-80, 2014 Nov 05.
Artículo en Inglés | MEDLINE | ID: mdl-25729320

RESUMEN

In this work, it is shown that novel aqueous two-phase systems can be formed by the combination of acetonitrile and polysaccharides, namely dextran. Several ternary phase diagrams were determined at 25 °C for the systems composed of water + acetonitrile + dextran. The effect of the dextran molecular weight (6,000, 40,000 and 100,000 g.mol-1) was ascertained toward their ability to undergo liquid-liquid demixing. An increase in the dextran molecular weight favors the phase separation. Furthermore, the effect of temperature (25, 35 and 45 °C) was evaluated for the system constituted by the dextran of higher molecular weight. Lower temperatures are favorable for phase separation since lower amounts of dextran and acetonitrile are required for the creation of aqueous two-phase systems. In general, acetonitrile is enriched in the top phase while dextran is majorly concentrated in the bottom phase. The applicability of this new type of two-phase systems as liquid-liquid extraction approaches was also evaluated by the study of the partition behavior of a well-known antioxidant - vanillin - and used here as a model biomolecule. The optimized conditions led to an extraction efficiency of vanillin of 95% at the acetonitrile-rich phase.

10.
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
11.
Appl Biochem Biotechnol ; 146(1-3): 189-201, 2008 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-18421598

RESUMEN

Thermoanaerobacter cyclomaltodextrin glucanotransferase (CGTase) was immobilized using different supports and immobilization methods to study the effect on activity recovery. The enzyme covalently attached into glyoxyl-silica showed low activity recovery of 1.5%. The hydrophobic adsorption of the enzyme on Octadecyl-Sepabeads yielded also low activity recovery, 3.83%, and the enzyme could easily leak from the support at low ionic strength, although the immobilization yield was satisfactory, approximately 76%. The CGTase encapsulated in a sol-gel matrix gave an activity recovery of 6.94% and maximum cyclization activity at 60 degrees C, at pH 6.0. The half-time life at 60 degrees C, pH 6.0, in the presence of substrate was 100 min, which was lower than that of the free enzyme. The best activity recovery in this work (6.94%) is approximately five times smaller than that obtained previously using glyoxyl-agarose as support and covalent immobilization. Thus, the best support and method we tested so far for immobilization of CGTase is covalent attachment on glyoxyl-agarose.


Asunto(s)
Glucosiltransferasas/química , Thermoanaerobacter/enzimología , Adsorción , Activación Enzimática , Estabilidad de Enzimas , Enzimas Inmovilizadas/química , Especificidad por Sustrato
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