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1.
Food Res Int ; 186: 114161, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38729685

RESUMEN

In this article, the synthesis of antioxidant peptides in the enzymatic hydrolysis of caprine casein was analyzed at three different time points (60 min, 90 min, and 120 min) using immobilized pepsin on activated and modified carbon (AC, ACF, ACG 50, ACG 100). The immobilization assays revealed a reduction in the biocatalysts' activity compared to the free enzyme. Among the modified ones, ACG 50 exhibited greater activity and better efficiency for reuse cycles, with superior values after 60 min and 90 min. Peptide synthesis was observed under all studied conditions. Analyses (DPPH, ß-carotene/linoleic acid, FRAP) confirmed the antioxidant potential of the peptides generated by the immobilized enzyme. However, the immobilized enzyme in ACG 50 and ACG 100, combined with longer hydrolysis times, allowed the formation of peptides with an antioxidant capacity greater than or equivalent to those generated by the free enzyme, despite reduced enzymatic activity.


Asunto(s)
Antioxidantes , Caseínas , Enzimas Inmovilizadas , Glutaral , Cabras , Iridoides , Pepsina A , Péptidos , Antioxidantes/química , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Caseínas/química , Animales , Pepsina A/metabolismo , Pepsina A/química , Glutaral/química , Péptidos/química , Iridoides/química , Hidrólisis , Carbón Orgánico/química
2.
J Sci Food Agric ; 103(14): 6947-6957, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37314022

RESUMEN

BACKGROUND: In recent years, the rising global demand for cheese, the high cost and limited supply of calf rennet, and consumer choices have increased research into new alternatives to animal or recombinant chymosins for cheese making. Plant proteases with caseinolytic activity (CA) and milk-clotting activity (MCA) have been proposed as alternatives for milk clotting to obtain artisanal cheeses with new organoleptic properties. They have been named vegetable rennets (vrennets). The aim of this study was to evaluate the performance of two Solanum tuberosum aspartic proteases (StAP1 and StAP3) as vrennets for cheese making and to obtain a statistical model that could predict and optimize their enzymatic activity. RESULTS: To optimize the CA and MCA activities, a response surface methodology was used. Maximum values of CA and MCA for both enzymes were found at pH 5.0 and 30-35 °C. Analysis of the degradation of casein subunits showed that it is possible to tune the specificity of both enzymes by changing the pH. At pH 6.5, the αS - and ß- subunit degradation is reduced while conserving a significant MCA. CONCLUSION: The statistical models obtained in this work showed that StAP1 and StAP3 exert CA and MCA under pH and temperature conditions compatible with those used for cheese making. The casein subunit degradation percentages obtained also allowed us to select the best conditions for the degradation of the κ-casein subunit by StAPs. These results suggest that StAP1 and StAP3 are good candidates as vrennets for artisan cheese making. © 2023 Society of Chemical Industry.


Asunto(s)
Queso , Solanum tuberosum , Animales , Solanum tuberosum/metabolismo , Queso/análisis , Caseínas/química , Quimosina/análisis , Ácido Aspártico Endopeptidasas , Péptido Hidrolasas/metabolismo , Leche/química
3.
J Agric Food Chem ; 71(19): 7495-7507, 2023 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-37157171

RESUMEN

Caseins are the main proteins in milk, and their structure and spatial conformation are responsible for their slow digestion rate. The release of bioactive and ß-casomorphin peptides from casein digestion may induce allergic responses during consumption. Spectroscopic techniques were used to observe the structural changes in casein conformation induced by Ultraviolet light irradiation (UV-C). Raman spectroscopy results showed more pronounced peaks at 618 and 640 cm-1 for phenylalanine and tyrosine moieties of the photolyzed micellar casein, respectively, suggesting changes in the micelle structure. The decrease in the intensity of Raman signals for tryptophan and tyrosine corroborates to the UV-C-induced modifications of the micelle structure. Particle size distribution showed a decrease in the average micelle size after 15 min of UV-C exposure, while low-temperature, long-time (LTLT) pasteurization led to the formation of large aggregates, as observed by atomic force microscopy. UV-C did not impact the formation or transport of peptides, as observed by using the Caco-2 cell as a model for peptide absorption. However, the absence of the opioid peptide SRYPSY from κ-casein and only 20% of the concentration of opioid peptide RYLGY were noted. This work demonstrated that UV-C can be utilized to induce the physicochemical modification of dairy products, promoting a higher digestion rate and reducing allergenicity.


Asunto(s)
Proteolisis , Estómago , Caseínas/química , Caseínas/farmacología , Rayos Ultravioleta , Péptidos/metabolismo , Fenómenos Químicos , Células CACO-2 , Humanos , Estómago/efectos de los fármacos , Estómago/metabolismo , Proteolisis/efectos de los fármacos , Micelas , Tamaño de la Partícula
4.
Molecules ; 27(21)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36364012

RESUMEN

The effect of different high-pressure processing (HPP) treatments on casein micelles was analyzed through scanning electron microscopy (SEM) and a particle size distribution analysis. Raw whole and skim milk samples were subjected to HPP treatments at 400, 500 and 600 MPa for Come-Up Times (CUT) up to 15 min at ambient temperature. Three different phenomena were observed in the casein micelles: fragmentation, alterations to shape and agglomeration. The particle size distribution analysis determined that, as pressure and time treatment increased, the three phenomena intensified. First, the size of the casein micelles began to decrease as their fragmentation occurred. Subsequently, the casein micelles lost roundness, and their shape deformed. Finally, in the most intense treatments (higher pressures and/or longer times), the micelles fragments began to agglomerate, which resulted in an increase in their average diameter. Homogenization and defatting had no significant effect on the casein micelles; however, the presence of fat in whole milk samples was bioprotective, as the effects of the three phenomena appeared faster in treated skim milk samples. Through this study, it was concluded that the size and structure of casein micelles are greatly altered during high-pressure treatment. These results provide information that broadens the understanding of the changes induced on casein micelles by high-pressure treatments at room temperature.


Asunto(s)
Caseínas , Micelas , Animales , Caseínas/química , Leche/química , Proteínas de la Leche/química
5.
Int J Biol Macromol ; 192: 931-938, 2021 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-34656538

RESUMEN

In recent years, many attempts have been made to find new plant proteases to make artisan cheeses. The global increase in cheese consumption, together with a lower supply and increasing cost of calf rennet, religious factors (Islam and Judaism) and food choices (vegetarianism) have led to the search for suitable rennet substitutes for milk clotting. This study describes the milk-clotting and hydrolytic activities of an aspartic protease from Salpichroa origanifolia fruits (SoAP) on individual caseins to explore its potential use as an alternative to animal rennet. The milk-clotting index obtained for SoAP was 8.4 times lower than that obtained for chymosin. SoAP showed a higher degree of hydrolysis on α-casein than on the other fractions under the proposed conditions. RP-HPLC, mass spectrometry analyses and sequencing of the hydrolysates allowed identifying five peptides from α-casein, one peptide from ß-casein, and three peptides from k-casein. In silico analysis showed that the peptides identified may display a wide variety of potential biological activities. These results demonstrate the possibility of using SoAP for the manufacture of new types or artisan cheeses, with the simultaneous added value of the potential health-promoting benefits of the bioactive peptides generated during the hydrolysis.


Asunto(s)
Proteasas de Ácido Aspártico/química , Caseínas/química , Frutas/enzimología , Leche/química , Solanaceae/enzimología , Animales , Proteasas de Ácido Aspártico/aislamiento & purificación , Queso/análisis , Fenómenos Químicos , Activación Enzimática , Frutas/química , Hidrólisis , Cinética , Extractos Vegetales , Solanaceae/química , Relación Estructura-Actividad
6.
Life Sci ; 284: 119910, 2021 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-34453939

RESUMEN

AIMS: Quercetin has been investigated as an agent to treat rheumatoid arthritis. At high doses it improves inflammation and the antioxidant status of arthritic rats, but it also exerts mitochondriotoxic and pro-oxidant activities. Beneficial effects of quercetin have not been found at low doses because of its chemical instability and low bioavailability. In the hope of overcoming these problems this study investigated the effects of long-term administration of quercetin-loaded pectin/casein microparticles on the oxidative status of liver and brain of rats with adjuvant-induced arthritis. MAIN METHODS: Particle morphology was viewed with transmission electron microscopy and the encapsulation efficiency was measured indirectly by X-ray diffraction. Quercetin microcapsules (10 mg/Kg) were orally administered to rats during 60 days. Inflammation indicators and oxidative stress markers were measured in addition to the respiratory activity and ROS production in isolated mitochondria. KEY FINDINGS: Quercetin was efficiently encapsulated inside the polymeric matrix, forming a solid amorphous solution. The administration of quercetin microparticles to arthritic rats almost normalized protein carbonylation, lipid peroxidation, the levels of reactive oxygen species as well as the reduced glutathione content in both liver and brain. The paw edema in arthritic rats was not responsive, but the plasmatic activity of ALT and the mitochondrial respiration were not affected by quercetin, indicating absence of mitochondriotoxic or hepatotoxic actions. SIGNIFICANCE: Quercetin-loaded pectin/casein microcapsules orally administered at a low dose improve oxidative stress of arthritic rats without a strong anti-inflammatory activity. This supports the long-term use of quercetin as an antioxidant agent to treat rheumatoid arthritis.


Asunto(s)
Artritis Experimental/patología , Caseínas/química , Microesferas , Estrés Oxidativo , Pectinas/química , Quercetina/farmacología , Alanina Transaminasa/sangre , Animales , Antioxidantes/farmacología , Artritis Experimental/sangre , Encéfalo/efectos de los fármacos , Encéfalo/patología , Rastreo Diferencial de Calorimetría , Respiración de la Célula/efectos de los fármacos , Edema/patología , Hígado/efectos de los fármacos , Hígado/patología , Masculino , Mitocondrias Hepáticas/efectos de los fármacos , Mitocondrias Hepáticas/metabolismo , Estrés Oxidativo/efectos de los fármacos , Oxidorreductasas/metabolismo , Ratas , Especies Reactivas de Oxígeno/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Difracción de Rayos X
7.
Int J Biol Macromol ; 183: 276-284, 2021 Jul 31.
Artículo en Inglés | MEDLINE | ID: mdl-33892034

RESUMEN

Aqueous two-phase system (ATPS) is a technique used for the separation of biopolymers in two aqueous phases. Some combinations of biopolymers can form a water-in-water (W/W) emulsion due to steric exclusion and thermodynamic incompatibility between these biopolymers under some specific conditions. In this work, the formation of W/W emulsions composed of sodium caseinate (SCN) and locust bean gum (LBG) was evaluated, using NaCl or yerba mate extract as the driving force for the phase separation, which was described by phase's diagrams. Phase diagrams are like fingerprints of ATPS systems, which demonstrate the specific conditions to develop separate phases. Phase diagrams of the two systems show that at the same concentrations of protein and carbohydrate, the addition of NaCl or extract induced the separation of the compounds differently. Salt promotes phase separation by steric exclusion, each phase being rich in one of the polymers. Since extract may also induce other effects, such as the formation of a SCN-extract-LBG complex, migration of LBG to the SCN-rich phase was promoted, modifying the characteristics of the tie lines in the phase diagrams. However, it was feasible to separate the protein in systems containing concentrated phenolic extract, whose incorporation is relevant considering its antioxidant activity.


Asunto(s)
Caseínas/química , Galactanos/química , Mananos/química , Gomas de Plantas/química , Cloruro de Sodio/química , Nanofibras/química , Polímeros/química
8.
J Dairy Res ; 87(3): 379-381, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32718372

RESUMEN

We evaluated the effects of fermentation time and acid casein content on the microbial rennet obtained by solid-state fermentation using wheat bran as the carbon source. The experiments used two fermentation times (72 and 96 h), while acid casein content was 1.5, 2.0, 2.5, and 3.0 g. Rennet strength from eight enzymatic extracts was measured using pasteurized whole milk. Rennet strength of samples from 72 h of fermentation showed an increase when acid casein content increased. The rennet strength increased at 96 h of fermentation with increasing amount of casein (up to 2.5 g), and then decreased with the largest addition (3.0 g) of casein. Coagulation time for the sample with highest rennet strength was 420 s.


Asunto(s)
Bacterias/metabolismo , Caseínas/química , Caseínas/metabolismo , Quimosina/metabolismo , Nitrógeno/metabolismo , Fermentación
9.
Biotechnol Lett ; 42(11): 2403-2412, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32642979

RESUMEN

OBJECTIVES: Keratinases are proteolytic enzymes that emerge as an alternative for dealing with the disposal of chicken feathers. In this study, we aimed to investigate the keratin-degrading enzymes secreted by the fungus Coriolopsis byrsina and their partial biochemical characterization to adapt their use for keratin decomposition, detergent additive applications, and collagen degradation. RESULTS: We observed the secretion of different proteolytic enzymes that possessed caseinolytic activity that peaked at pH 7.0-9.0 and 60-70 °C and at pH 10.5 and 55-60 °C, and keratinolytic activity that reached a maximum at pH 7.0-7.5 and 40-55 ºC and at pH 9.0 and 55 °C. Keratinolytic activity was maintained at approximately 63% of residual activity for 1 h at 50 °C. The caseinolytic activity at pH 10.5 remains stable until 1 h at 50 °C, and this is in contrast to the activity at pH 8.5, where the residual activity was 50%. Caseinolytic activity was inhibited only by PMSF, while keratinolytic activity was inhibited by PMSF and EDTA. When investigating the application of C. byrsina peptidases as an additive to commercial detergent, we observed an egg stain removal performance that was similar to that demonstrated by the commercial detergent. CONCLUSIONS: Based on their activity and stability at alkaline pH, these enzymes appear to be attractive candidates for use in the detergent industry. Additionally, the collagenolytic activity of these enzymes potentially allows for their use in a wide array of industrial sectors that require collagenolytic enzymes, such as for the production of collagen hydrolysates from residues derived from the meat industry.


Asunto(s)
Plumas/química , Péptido Hidrolasas/química , Péptido Hidrolasas/metabolismo , Polyporaceae/crecimiento & desarrollo , Animales , Técnicas de Cultivo Celular por Lotes , Caseínas/química , Estabilidad de Enzimas , Fermentación , Proteínas Fúngicas/metabolismo , Calor , Concentración de Iones de Hidrógeno , Polyporaceae/enzimología , Textiles
10.
Molecules ; 25(10)2020 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-32443501

RESUMEN

Nonsteroidal anti-inflammatory drug (NSAID)-induced enteropathy is considered a serious and increasing clinical problem without available treatment. Glycomacropeptide (GMP) is a 64-amino acid peptide derived from milk κ-casein with numerous biological activities. The aim of this study was to investigate the protective effect of GMP on NSAID enteropathy in rats. Enteropathy was induced by seven days oral indomethacin administration. Rats were orally GMP treated from seven days previous and during the establishment of the enteropathy model. Changes in metabolism, hematological and biochemical blood alterations, intestinal inflammation and oxidative damage were analyzed. Integrity barrier markers, macroscopic intestinal damage and survival rate were also evaluated. GMP treatment prevented anorexia and weight loss in animals. Furthermore, prophylaxis with GMP ameliorated the decline in hemoglobin, hematocrit, albumin and total protein levels. The treatment had no therapeutic efficacy on the decrease of occludin and mucin (MUC)-2 expression in intestinal tissue. However, GMP markedly decreased neutrophil infiltration, and CXCL1, interleukin-1ß and inducible nitric oxide synthase expression. Nitric oxide production and lipid hydroperoxide level in the small intestine were also diminished. These beneficial effects were mirrored by preventing ulcer development and increasing animal survival. These results suggest that GMP may protect against NSAID enteropathy through anti-inflammatory and antioxidant properties.


Asunto(s)
Caseínas/química , Inflamación/tratamiento farmacológico , Estrés Oxidativo/efectos de los fármacos , Fragmentos de Péptidos/química , Enteropatías Perdedoras de Proteínas/tratamiento farmacológico , Animales , Caseínas/farmacología , Quimiocina CXCL1/genética , Modelos Animales de Enfermedad , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Indometacina/toxicidad , Inflamación/inducido químicamente , Inflamación/complicaciones , Inflamación/patología , Interleucina-1beta/genética , Mucosa Intestinal , Proteínas de la Leche/química , Proteínas de la Leche/farmacología , Mucina 2/genética , Óxido Nítrico Sintasa de Tipo II/genética , Fragmentos de Péptidos/farmacología , Enteropatías Perdedoras de Proteínas/inducido químicamente , Enteropatías Perdedoras de Proteínas/complicaciones , Enteropatías Perdedoras de Proteínas/genética , Ratas
11.
Artículo en Inglés | MEDLINE | ID: mdl-32361468

RESUMEN

The present study aimed to evaluate the effect of the immobilization method of trypsin on biochar on the hydrolysis of casein from different sources, when compared to the process using trypsin in native form, to obtain bioactive peptides. The modification of the surface of biochar with glutaraldehyde was effective, as shown by the results of FTIR assay and the texture profile of the materials. Both activated and functionalized biochar showed high immobilization efficiency (greater than 87%) and high binding capacity (greater than 91 mg/g). During hydrolysis, the biocatalyst obtained by enzyme immobilization on the functionalized biochar presented a higher hydrolysis capacity for the different caseins when compared to the enzyme immobilized by adsorption, with values of 3.05 and 2.73 U/mg for goat casein, 2.36 and 1.85 U/mg for bovine casein, and 2.60 and 2.37 U/mg for buffalo, casein, respectively, with 60 min of reaction. The results of inhibitory activity in this study ranged from 93.5% and 25.5% for trypsin in its free form and immobilized on functionalized activated carbon, respectively, under the same reaction conditions. The immobilization methods were efficient, presenting high immobilization capacity. The proteolytic activity of trypsin immobilized via covalent binding was higher when compared the immobilization by adsorption. Thus, the functionalized biochar has proven to be potential support for enzyme immobilization, and the biocatalyst can be reused for more than 4 cycles. Despite lower ACE inhibition values of hydrolyzed obtained with the immobilized enzymes compared to free enzymes, biocatalysts present advantage due to the possibility of reuse.


Asunto(s)
Caseínas/química , Carbón Orgánico/química , Enzimas Inmovilizadas/química , Enzimas Inmovilizadas/metabolismo , Tripsina/química , Tripsina/metabolismo , Adsorción , Animales , Biocatálisis , Bovinos , Estabilidad de Enzimas , Glutaral/química , Concentración de Iones de Hidrógeno , Hidrólisis , Cinética , Ácidos Fosfóricos/química , Proteolisis , Propiedades de Superficie , Temperatura
12.
Int J Biol Macromol ; 154: 446-455, 2020 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-32194104

RESUMEN

In this work, we report the synthesis of graft copolymers based on casein and N-isopropylacrylamide, which can self-assemble into biodegradable micelles of approximately 80 nm at physiological conditions. The obtained copolymers were degraded by trypsin, an enzyme that is overexpressed in several malignant tumors. Moreover, graft copolymers were able to load doxorubicin (Dox) by ionic interaction with the casein component. In vitro release experiments showed that the in situ assembled micelles can maintain the cargo at plasma conditions but release Dox immediately after their exposition at pH 5.0 and trypsin. Cellular uptake and cytotoxicity assays revealed the efficient delivery to the nucleus and antiproliferative efficacy of Dox in the breast cancer cell line MDA231. Both delivery and therapeutic activity were enhanced in presence of trypsin. Overall, the prepared micelles hold a great potential for their utilization as dual responsive trypsin/pH drug delivery system.


Asunto(s)
Acrilamidas/química , Antineoplásicos/química , Caseínas/química , Doxorrubicina/química , Portadores de Fármacos/química , Polímeros/química , Temperatura , Antineoplásicos/farmacología , Transporte Biológico , Línea Celular Tumoral , Portadores de Fármacos/metabolismo , Humanos , Concentración de Iones de Hidrógeno , Polímeros/metabolismo
13.
Int J Biol Macromol ; 151: 178-185, 2020 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32044371

RESUMEN

Biodegradable films based on pure gelatin (GEL100), chitosan (CH100) and sodium caseinate (SCas100), and gelatin-chitosan (GEL50:CH50) and gelatin­sodium caseinate (GEL50:SCas50) blends, without or with boldo-of-Chile leafs extract (BoC) were studied. The solubility in water (%) of all the pure films was analyzed. Moreover, the disintegration process was evaluated throughout the mass loss (%), structural (FTIR) changes and visual analyses of films up to 5 days of composting conditions. The Boltzmann function allowed obtaining the half-maximal disintegration time (t50) of all the films. Only Scas100 films exhibited complete solubility in water, compared to the other films (P < 0.05). At day 1, SCas100 + B film exhibited total mass loss, meanwhile for the other film samples this parameter varied between 47.9 ± 3.0% (CH100 + B) and 6.8 ± 1.3% (GEL100 + B) (P < 0.05). FTIR analysis showed some changes in the intensity of the typical bands of the pure or blended films. Photographs registered exhibited the complete disintegration of all films into 5 days. Finally, Boltzmann equation displayed that pure SCas100 film disintegrated in the shortest time (0.500 days), and GEL50:CH50 blended film in the longest time (1.766 days). In conclusion, the results of this work show an appropriate and complete disintegration of all studied films in composting conditions.


Asunto(s)
Caseínas/química , Quitosano/química , Gelatina/química , Extractos Vegetales/química , Biopolímeros/química , Fenómenos Químicos , Hojas de la Planta/química , Sensibilidad y Especificidad , Solubilidad , Análisis Espectral , Agua/química
14.
Food Chem ; 314: 126063, 2020 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-31951886

RESUMEN

Casein-based hydrogels are biocompatible, biodegradable, renewable, easy to obtain, inexpensive, and non-toxic. They exist in different physicochemical states, e.g. particle hydrogels, which can be dived in suspensions or emulsions and macro hydrogels that are gel colloid type. These biomaterials have drawn increasing attention in recent years due to their abilities to form networks of different tensile strengths and to encapsulate, protect and release biomolecules. This mini-review outlines the recent advances in casein-based hydrogel research and the uses of casein-based hydrogels as drug delivery system for both hydrophobic and hydrophilic molecules. The food and biomedical potential along with possible future uses of the casein-based hydrogels are discussed throughout the document.


Asunto(s)
Caseínas/química , Hidrogeles/química , Animales , Materiales Biocompatibles/química , Sistemas de Liberación de Medicamentos , Alimentos , Humanos
15.
Int J Biol Macromol ; 148: 302-315, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-31931066

RESUMEN

In this study, the materials were synthesized by chemically crosslinking chondroitin sulfate (CS), casein (CAS), and silica nanospheres (SiO2), creating a highly crosslinked network. The hydrogel release profile was adaptable (that is, it could be faster or slower as needed) simply by changing the polymeric proportion. The incorporation of 5% of silica nanospheres, in mass, for all CAS/CS matrices promoted a better-controlled and sustained release of l-dopa, focusing on the matrix based on 70% of CAS, 30% of CS and 5% of silica, whose l-dopa release lasted for 87 h. Besides, hydrogels are cytocompatible. These new hydrogels can be considered highly attractive materials to be used for controlled and sustained drug release purposes, as well as scaffolds and wound dressing systems.


Asunto(s)
Caseínas/química , Sulfatos de Condroitina/química , Preparaciones de Acción Retardada/química , Hidrogeles/química , Nanosferas/química , Dióxido de Silicio/química , Materiales Biocompatibles/química , Reactivos de Enlaces Cruzados/química , Sistemas de Liberación de Medicamentos/métodos , Liberación de Fármacos , Concentración de Iones de Hidrógeno , Polietilenglicoles/química , Polímeros/química
16.
Food Chem ; 309: 125764, 2020 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-31771916

RESUMEN

Coating fruits surface with biodegradable films obtained from starch is an alternative to delay the fruit ripening process. This study aimed to develop a biodegradable film from a polymer blend consisting of natural cassava starch, casein, and gelatin, and using sorbitol as the plasticizer. Among all the prepared biodegradable films (BFs), the one with desirable results in thickness, opacity, solubility, and water vapor transmission rate (WVTR) analyzes was based on a high concentration of starch, and casein, and low concentration of gelatin. Also, this film had the lowest solubility among all of them. Guava fruit coated with this film showed a two-day increase in shelf-life when compared to non-coated guavas. The increase in shelf-life was due to the extremely low water vapor transmission rate of the films, decreasing the fruits' mass loss, and, consequently, retarding their senescence. These results indicate that the biodegradable film is a promising material for fruit coating.


Asunto(s)
Caseínas/química , Películas Comestibles , Gelatina/química , Almidón/química , Frutas/química , Permeabilidad , Psidium/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Agua/química
17.
J Biomol Struct Dyn ; 38(18): 5389-5400, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31814537

RESUMEN

Tetracycline (TC), oxytetracycline (OTC), and chlortetracycline (CTC) interactions with the allergenic milk protein casein (CAS) were here evaluated simulating food conditions. The antibiotics assessed interact with CAS through static quenching and form non-fluorescent complexes. At 30 °C, the binding constant (Kb) varied from 0.05 to 1.23 × 106 M-1. Tetracycline interacts with CAS preferably through electrostatic forces, while oxytetracycline and chlortetracycline interactions occur by hydrogen bonds and van der Waals forces. The interaction process is spontaneous, and the magnitude of interaction based on Kb values, followed the order: TC < CTC < OTC. The distances between the donor (protein) and the receptors (TC, OTC, and CTC) were determined by Förster resonance energy transfer (FRET) and varied from 3.67 to 4.08 nm. Under natural feeding conditions, the citrate decreased the affinity between TC and CAS; a similar effect was observed for OTC in the presence of Ca(II), Fe(III) and lactose. Synchronized and three-dimensional (3D) fluorescence studies indicated alterations in the original protein conformation due to the interaction process, which may influence allergenic processes. In addition, complexation with CAS modulated the antimicrobial activity of CTC against S. aureus, demonstrated that the interaction process possibly alters the biological properties of antibiotics and the own protein, in the food conditions.Communicated by Ramaswamy H. Sarma.


Asunto(s)
Alérgenos , Caseínas , Proteínas de la Leche , Tetraciclinas , Antibacterianos/farmacología , Caseínas/química , Compuestos Férricos , Staphylococcus aureus , Tetraciclinas/farmacología
18.
Int J Biol Macromol ; 138: 244-251, 2019 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-31279877

RESUMEN

The objective of this study was to develop zein-casein-lysine nanoparticles to modulate the intestinal permeability of ferulic acid (FA), a bioactive compound with proven antioxidant properties. The nanoparticles were obtained by a liquid-liquid dispersion method and were characterized in terms of mean size, polydispersity index, zeta potential, association efficiency (AE), in vitro drug release, x-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The in vitro intestinal permeability of nanoparticles was evaluated through Caco-2 and Caco-2/HT29-MTX monoculture and co-culture models, respectively. Nanoparticles presented a mean size of 199 nm and zeta potential of -26 mV. The AE of FA was 23% evaluated by high-performance liquid chromatography (HPLC). XRD showed amorphization of FA after association and FT-IR showed no changes in chemical structures of the compounds after nanoencapsulation. The cytotoxicity assays demonstrated that multicomposite nanoparticles presented a safe profile against Caco-2 and HT29-MTX cells. In the in vitro permeability assay, free FA exhibited higher permeability compared to FA-loaded nanoparticles, possibly due to prolonged FA release from nanoparticles. These new developed zein-casein-lysine nanoparticles may be used for FA sustained delivery by the oral route.


Asunto(s)
Caseínas/química , Ácidos Cumáricos/química , Ácidos Cumáricos/farmacología , Mucosa Intestinal/metabolismo , Lisina/química , Nanopartículas/química , Zeína/química , Administración Oral , Células CACO-2 , Supervivencia Celular/efectos de los fármacos , Ácidos Cumáricos/administración & dosificación , Portadores de Fármacos/química , Liberación de Fármacos , Humanos , Mucosa Intestinal/efectos de los fármacos
19.
J Pediatr ; 213: 137-142.e2, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31327562

RESUMEN

OBJECTIVE: To investigate whether the addition of the probiotic Lactobacillus rhamnosus GG (LGG) to the extensively hydrolyzed casein formula (EHCF) for cow's milk allergy (CMA) treatment could reduce the occurrence of functional gastrointestinal disorders (FGIDs). STUDY DESIGN: This cohort study included children with a positive history for CMA in the first year of life who were treated with EHCF alone or in combination with LGG and had evidence of immune tolerance acquisition to cow's milk for at least 12 months. FGID was diagnosed according to the Rome III diagnostic criteria by investigators unaware of previous treatment. A cohort of consecutive healthy children was also evaluated as a control population. RESULTS: A total of 330 subjects were included, 110 per cohort (EHCF, EHCF+LGG, and healthy controls). The rate of subjects with ≥1 FGID was significantly lower in the EHCF+LGG cohort compared with the EHCF cohort (40% vs 16.4%; P < .05). In the EHCF+LGG cohort, a lower incidence was observed for all components of the main study outcome. The prevalence of FGIDs in the healthy cohort was lower than that in the EHCF cohort and similar to that in the EHCF+LGG cohort. The incidence rate ratio of FGIDs for the EHCF+LGG cohort vs the EHCF cohort (0.40; 95% CI, 0.25-0.65; P < .001) was unmodified after correction for age at CMA diagnosis, breastfeeding, weaning time, and presence of a first-degree relative with an FGID. CONCLUSIONS: These results confirm the increased risk for developing FGIDs in children with CMA and suggest that EHCF+LGG could reduce this risk.


Asunto(s)
Caseínas/química , Alimentos Formulados , Enfermedades Gastrointestinales/prevención & control , Lacticaseibacillus rhamnosus , Hipersensibilidad a la Leche/dietoterapia , Probióticos/administración & dosificación , Animales , Bovinos , Niño , Preescolar , Dieta , Femenino , Humanos , Hidrólisis , Tolerancia Inmunológica , Masculino , Leche , Prevalencia , Estudios Prospectivos , Riesgo , Resultado del Tratamiento
20.
J Microencapsul ; 36(5): 459-473, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31322456

RESUMEN

This study was aimed to microencapsulate fish oil (FO) in two biocompatible polymeric blends: gum arabic (GA)-maltodextrin (MD) and casein-pectin (CP)-MD. GA-MD microparticles and CP-MD microparticles were produced by spray-drying and complex coacervation and spray-drying, respectively. Encapsulation efficiency, particle size, moisture content, oxidative stability, and morphological properties were analysed. Encapsulation efficiencies of 51.2-56.8% (w/v) for GA and 64.7-67.9% (w/v) for CP preparations were found. GA particle sizes varied from 2 to 100 µm and from 2 to 120 µm for CP microparticles. Spherical forms with depressions in the topography of both systems were evidenced by scanning electron microscopy. Confocal microscopy evidenced surface oil on GA microparticles, corroborating encapsulation efficiency. CP was more efficient than GA to reduce oxidation, with maximum peroxide values (PVs) of 17.40 mmol/kg oil after 28 d at 40 °C/75% relative humidity (RH). Thus, CP is a promising biopolymeric blend for encapsulation of FO that provides protection against lipid oxidation.


Asunto(s)
Caseínas/química , Excipientes/química , Aceites de Pescado/administración & dosificación , Goma Arábiga/química , Pectinas/química , Cápsulas , Composición de Medicamentos , Aceites de Pescado/química , Oxidación-Reducción , Polisacáridos/química
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