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Métodos Terapéuticos y Terapias MTCI
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1.
Food Res Int ; 182: 114160, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38519185

RESUMEN

Aqueous enzymatic extraction (AEE) of macauba pulp oil (MPO) was performed in this study with five commercial enzymatic pools. The chemical, nutritional, and thermal properties of the oils with high oil efficiency by AEE were evaluated and compared with mechanical pressing (MP) and organic solvent extraction (SE). Among the AEE processes, the pectinase pool (at pH 5.5 and 50 °C) exhibited the highest process efficiency (88.6 %). The oils presented low acidity values (0.4-3.1 %) and low molar absorptivities, indicating minimal oil degradation. Bioactive compounds, such as carotenoids, were found in MPO. The iodine index and the fatty acid profile of the oils revealed a high content of unsaturated fatty acids, particularly oleic and linoleic acids, with excellent nutritional scores, as evidenced by anti-atherogenicity and anti-thrombogenicity indices. These findings emphasized that AEE is an eco-friendly approach for extracting high-quality MPO with beneficial health compounds for food products.


Asunto(s)
Ácidos Grasos , Aceites de Plantas , Aceites de Plantas/química , Ácidos Grasos/análisis , Ácidos Grasos Insaturados/análisis , Antioxidantes/análisis , Semillas/química , Agua/análisis
2.
Food Res Int ; 179: 114016, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38342537

RESUMEN

Chocolate is a worldwide consumed food. This study investigated the fortification of sugar-free white chocolate with Lacticaseibacillus rhamnosus GG microcapsule co-encapsulated with beet residue extract. The chocolates were evaluated for moisture, water activity, texture, color properties, melting, physicochemical, and probiotic stability during storage. Furthermore, the survival of L. rhamnosus GG and the bioaccessibility of phenolic compounds were investigated under in vitro simulated gastrointestinal conditions. Regarding the characterization of probiotic microcapsules, the encapsulation efficiency of L. rhamnosus GG was > 89 % while the encapsulation efficiency of phenolic compounds was > 62 %. Chocolates containing probiotic microcapsules were less hard and resistant to breakage. All chocolates had a similar melting behavior (endothermic peaks between 32.80 and 34.40 °C). After 120 days of storage at 4 °C, probiotic populations > 6.77 log CFU/g were detected in chocolate samples. This result demonstrates the potential of this matrix to carry L. rhamnosus GG cells. Regarding the resistance of probiotic strains during gastric simulation, the co-encapsulation of L. rhamnosus GG with beet extract contributed to high counts during gastrointestinal transit, reaching the colon (48 h) with viable cell counts equal to 11.80 log CFU/g. Finally, one of our main findings was that probiotics used phenolic compounds as a substrate source, which may be an observed prebiotic effect.


Asunto(s)
Beta vulgaris , Chocolate , Lacticaseibacillus rhamnosus , Cápsulas , Extractos Vegetales
3.
Biotechnol Lett ; 45(2): 287-298, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36592260

RESUMEN

Lipase B from Candida antarctica (CalB) is one of the biocatalysts most used in organic synthesis due to its ability to act in several medium, wide substrate specificity and enantioselectivity, tolerance to non-aqueous environment, and resistance to thermal deactivation. Thus, the objective of this work was to treat CalB in supercritical carbon dioxide (SC-CO2) and liquefied petroleum gas (LPG), and measure its activity before and after high-pressure treatment. Residual specific hydrolytic activities of 132% and 142% were observed when CalB was exposed to SC-CO2 at 35 â„ƒ, 75 bar and 1 h and to LPG at 65 â„ƒ, 30 bar and 1 h, respectively. Residual activity of the enzyme treated at high pressure was still above 100% until the 20th day of storage at low temperatures. There was no difference on the residual activity loss of CalB treated with LPG and stored at different temperatures over time. Greater difference was observed between CalB treated with CO2 and flash-frozen in liquid nitrogen (- 196 â„ƒ) followed by storage in freezer (- 10 â„ƒ) and CalB stored in freezer at - 10 â„ƒ. Such findings encourage deeper studies on CalB as well as other enzymes behavior under different types of pressurized fluids aiming at industrial application.


Asunto(s)
Enzimas Inmovilizadas , Lipasa , Dióxido de Carbono , Proteínas Fúngicas
4.
Plant Foods Hum Nutr ; 76(1): 90-97, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33517518

RESUMEN

Jambolan is an unexplored fruit rich in bioactive compounds like anthocyanins, catechin, and gallic acid. Thus, the extraction of bioactive compounds allows adding value to the fruit. In this context, the present study reports the recovery and concentration of jambolan fruit extract by ultra and nanofiltration for the first time. Acidified water was used to extract polyphenols from the pulp and peel of jambolan. The extracts were concentrated using ultrafiltration and nanofiltration membranes with nominal molecular weight cut-off ranging from 180 to 4000 g mol-1. Total monomeric anthocyanin, total phenolic compounds, and antioxidant capacity were analyzed. Phenolic compounds were quantified, and anthocyanins were identified by high-performance liquid chromatography coupled to diode-array detection and mass spectrometry (HPLC-DAD-MS). Concentration factors higher than 4.0 were obtained for anthocyanins, gallic acid, and catechin after nanofiltration of the extracts. Other compounds such as epicatechin, p-Coumaric acid, and ferulic acid were quantified in the concentrated extract, and the main anthocyanins identified were 3,5-diglucoside: petunidin, malvidin, and delphinidin. Therefore, jambolan extract showed a high potential to be used as a natural dye and antioxidant in food products.


Asunto(s)
Syzygium , Antocianinas/análisis , Antioxidantes , Cromatografía Líquida de Alta Presión , Frutas/química , Fenoles/análisis , Extractos Vegetales
5.
Environ Technol ; 38(23): 2928-2938, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28088876

RESUMEN

The separation of Jatropha curcas oil from azeotropes of ethyl alcohol-n-hexane and isopropyl alcohol-n-hexane using ceramic membranes with different cutoffs (5, 10 and 20 kDa) is presented. The mass ratios of oil:azeotropes (O:S) studied were 1:3 for feeding pressures of 0.1, 0.2 and 0.3 MPa, and 1:1 for the feeding pressure of 0.1 MPa. Isopropyl alcohol was the best solvent for the membranes conditioning to permeate n-hexane (240 kg/m2 h). In the separation of J. curcas oil and azeotropes of solvents, both membranes showed oil retention and total flux decreases with time. Overall, the lowest decrease in the retentions was reached in the 5 kDa membrane, while the lowest decrease in the total flux was reached in the 20 kDa. In the separation of oil and ethyl alcohol-n-hexane azeotrope, the best retention at 60 min of the process was equal to 17.3 wt% in the 20 kDa membrane at 0.3 MPa and O:S ratio equalled to 1:3. In this condition, the total permeate flux was 17.5 kg/m2 h. Different retentions and permeabilities are provided when changing the O:S ratio, the feeding pressure and the molecular weight cutoff of membranes.


Asunto(s)
Cerámica/química , Fraccionamiento Químico/métodos , Jatropha/química , Aceites de Plantas/aislamiento & purificación , Solventes/química , 2-Propanol/química , Hexanos/química , Membranas Artificiales , Aceites de Plantas/química
6.
Environ Technol ; 38(16): 1969-1979, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27735225

RESUMEN

This work investigates the use of ceramic membranes with different molecular weight cut-offs (MWCOs: 5, 10 and 20 kDa) to desolventize azeotropic solvent mixtures (ethanol/n-hexane and isopropyl alcohol/n-hexane) from soybean oil/azeotrope micelles. Results show that a decrease in the MWCO of a membrane and an increase in the solvent mass ratio in the mixture resulted in a significant reduction in the permeate flux. The 20 kDa membrane presented the highest permeate flux, 80 and 60 kg/m2h for the soybean oil/n-hexane/isopropyl alcohol and soybean oil/n-hexane/ethanol azeotropes, respectively, for an oil to solvent ratio of 1:3 (w/w). The highest oil retention was found using the n-hexane/isopropyl alcohol azeotrope, around 25% in the membrane with the lowest MWCO, that is, 5 kDa. It is shown that the azeotropic mixtures provided intermediate characteristics compared to the original pure solvent behavior.


Asunto(s)
Cerámica , Aceite de Soja , 2-Propanol , Membranas Artificiales , Solventes
7.
J Biotechnol ; 147(2): 108-15, 2010 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-20347889

RESUMEN

This work reports new experimental data and mathematical modeling of lipase-catalyzed biodiesel production using soybean oil and ethanol as substrates and pressurized n-propane as solvent. The experiments were carried out in a batch reactor, recording the reaction kinetics and evaluating the effects of temperature in the range of 45-70 degrees C, enzyme content from 1 to 20 wt% and oil to ethanol molar ratios of 1:3, 1:6, 1:9 and 1:15. The solvent to substrates mass ratio and pressure were set at 2:1 and 50 bar, respectively. Results showed that lipase-catalyzed alcoholysis in propane medium might be a potential alternative to conventional techniques for biodiesel production, since good conversions were obtained at mild temperature and pressure conditions. The semi-empirical mathematical model based on balance equations, adopted to describe the transesterification kinetics in pressurized n-propane, yielded relative deviations between experimental and calculated values lower than 10%, thus allowing a satisfactory representation of experimental results and a better understanding of the transesterification reaction.


Asunto(s)
Biotecnología/métodos , Ésteres/metabolismo , Glicéridos/metabolismo , Lipasa/metabolismo , Propano/química , Biocombustibles , Reactores Biológicos , Biotecnología/instrumentación , Catálisis , Diseño de Equipo , Esterificación , Etanol/metabolismo , Cinética , Modelos Biológicos , Presión , Aceite de Soja/química , Temperatura
8.
Appl Biochem Biotechnol ; 121-124: 553-60, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15920262

RESUMEN

This article reports experimental data on the production of fatty acid ethyl esters from refined and degummed soybean oil and castor oil using NaOH as catalyst. The variables investigated were temperature (30-70 degrees C), reaction time (1-3 h), catalyst concentration (0.5-1.5 w/wt%), and oil-to-ethanol molar ratio (1:3-1:9). The effects of process variables on the reaction conversion as well as the optimum experimental conditions are presented. The results show that conversions >95% were achieved for all systems investigated. In general, an increase in reaction temperature, reaction time, and in oil-to-ethanol molar ratio led to an enhancement in reaction conversion, whereas an opposite trend was verified with respect to catalyst concentration.


Asunto(s)
Aceite de Ricino/química , Etanol/química , Ácidos Grasos/síntesis química , Hidróxido de Sodio/química , Aceite de Soja/química , Álcalis/química , Catálisis , Técnicas Químicas Combinatorias , Esterificación , Ésteres , Gasolina , Concentración de Iones de Hidrógeno , Temperatura
9.
Appl Biochem Biotechnol ; 121-124: 231-41, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15917602

RESUMEN

This work investigated the production of fatty acid ethyl esters (FAEEs) from soybean oil using n-hexane as solvent and two commercial lipases as catalysts, Novozym 435 and Lipozyme IM. A Taguchi experimental design was adopted considering the variables temperature (35-65 degrees C), addition of water (0-10 wt/wt%), enzyme (5-20 wt/wt%) concentration, and oil-to-ethanol molar ratio (1:3-1:10). It is shown that complete conversion in FAEE is achieved for some experimental conditions. The effects of process variables on reaction conversion and kinetics of the enzymatic reactions are presented for all experimental conditions investigated in the factorial design.


Asunto(s)
Alcoholes/química , Ácidos Grasos/síntesis química , Hexanos/química , Lipasa/química , Solventes/química , Aceite de Soja/química , Activación Enzimática , Enzimas Inmovilizadas/química , Ésteres , Proteínas Fúngicas , Hidrólisis , Cinética , Soluciones
10.
Appl Biochem Biotechnol ; 113-116: 173-80, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15054204

RESUMEN

The production of lipases by Penicillium simplicissimum using solid-state fermentation and soy cake as substrate was investigated. The effects of temperature, cake moisture, and carbon supplementation on lipase production were studied using a two-level experimental plan. Moisture, pH, and lipase activity were followed during fermentation. Statistical analysis of the results was performed to evaluate the effect of the studied variables on the maximum lipase activity. Incubation temperature was the variable that most affected enzyme activity, showing a negative effect. Moisture and carbon supplementation presented a positive effect on activity. It was possible to obtain lipase activity as high as 21 U/g of dry cake in the studied range of process variables.


Asunto(s)
Biotecnología/métodos , Carbono/química , Fermentación , Glycine max/microbiología , Lipasa/química , Penicillium/metabolismo , Medios de Cultivo , Concentración de Iones de Hidrógeno , Lipasa/biosíntesis , Aceite de Oliva , Aceites de Plantas , Temperatura , Factores de Tiempo
11.
Appl Biochem Biotechnol ; 113-116: 771-80, 2004.
Artículo en Inglés | MEDLINE | ID: mdl-15054231

RESUMEN

We studied the production of fatty acid ethyl esters from castor oil using n-hexane as solvent and two commercial lipases, Novozym 435 and Lipozyme IM, as catalysts. For this purpose, a Taguchi experimental design was adopted considering the following variables: temperature (35-65 degrees C), water (0-10 wt/wt%), and enzyme (5-20 wt/wt%) concentrations and oil-to-ethanol molar ratio (1:3 to 1:10). An empirical model was then built so as to assess the main and cross-variable effects on the reaction conversion and also to maximize biodiesel production for each enzyme. For the system containing Novozym 435 as catalyst the maximum conversion obtained was 81.4% at 65 degrees C, enzyme concentration of 20 wt/wt%, water concentration of 0 wt/wt%, and oil-to-ethanol molar ratio of 1:10. When the catalyst was Lipozyme IM, a conversion as high as 98% was obtained at 65 degrees C, enzyme concentration of 20 wt/wt%, water concentration of 0 wt/wt%, and oil-to-ethanol molar ratio of 1:3.


Asunto(s)
Biotecnología/métodos , Aceite de Ricino/química , Química Orgánica/métodos , Alcoholes/química , Catálisis , Ésteres/química , Etanol , Cinética , Lipasa/química , Modelos Estadísticos , Aceites de Plantas , Solventes , Temperatura , Factores de Tiempo
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