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1.
Arch Sex Behav ; 53(7): 2751-2763, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38553660

RESUMEN

Pre-exposure prophylaxis (PrEP) is a highly effective method for preventing HIV acquisition and plays a crucial role in the Ending the HIV Epidemic in the US initiative. However, there are various barriers that hinder the access and uptake of PrEP among Latino sexual minority men (SMM) at individual, interpersonal, and cultural levels. While the significance of cultural factors in designing and implementing HIV prevention programs for Latino populations has been consistently emphasized in the literature and prioritized by the Centers for Disease Control and Prevention, few studies have directly integrated these cultural factors into their programs. Our study aimed to investigate the potential influence of siblings in promoting the utilization of PrEP for HIV prevention, an area that has received limited attention. We conducted interviews with 31 pairs of siblings between December 2020 and January 2021, which were held in either English or Spanish and lasted approximately 45-60 min. The data were analyzed using a deductive thematic content analysis approach. The interviews revealed several key themes and categories, including: (1) Sibling support for coming out; (2) Types of support that siblings provide to each other for behavior change; (3) Sibling support for PrEP; and (4) The impact of the study interview on the quality of the sibling relationships. Our findings indicated that siblings were willing to provide support for PrEP in various ways, ranging from emotional support for brothers who may be concerned about potential rejection to practical support such as transportation or financial assistance. These results have significant implications for the design of HIV prevention interventions for Latinos. Incorporating siblings or other extended family members into these interventions can facilitate communication between siblings and their brothers, ultimately encouraging the use of PrEP or similar prevention methods. By considering the unique dynamics and support systems within Latino communities, researchers can develop more effective strategies to promote HIV prevention and support the well-being of Latino SMM.


Asunto(s)
Infecciones por VIH , Hispánicos o Latinos , Minorías Sexuales y de Género , Hermanos , Humanos , Masculino , Hispánicos o Latinos/psicología , Hispánicos o Latinos/estadística & datos numéricos , Adulto , Minorías Sexuales y de Género/psicología , Infecciones por VIH/prevención & control , Hermanos/psicología , Profilaxis Pre-Exposición/estadística & datos numéricos , Salud Sexual , Conducta Sexual/psicología , Persona de Mediana Edad , Adulto Joven
2.
J Sci Food Agric ; 102(7): 2630-2639, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-34997591

RESUMEN

Pseudocereals (amaranth, buckwheat and quinoa) are emerging as popular gluten-free crops. This may be attributed to their wide-ranging health benefits, including antioxidant, hypoglycemic and serum-cholesterol reducing properties. Proteins of these crops have a high nutritional quality as a result of the presence of essential amino acids. Additionally, amaranth, buckwheat and quinoa proteins (AP, BP and QP, respectively) have physicochemical properties that are useful for the manufacture of different types of food. However, native pseudocereal proteins demonstrate a low solubility in water, mainly because of their composition. The major components of these proteins are albumins (water-soluble) and globulins (salt-soluble), although some proportions of glutelin (alkali-soluble) and prolamins (alcohol-soluble) are also found. The most commonly used method for extracting pseudocereal proteins is the alkaline extraction method, which may contribute to the low solubility of pseudocereal protein. Fortunately, different methods for modifying physicochemical (or techno-functional) properties have been proposed to extend their industrial application. For example, high-intensity ultrasound (HIUS) proved useful for improving the solubility of API and QP. Heating can allow for the formation of soluble aggregates of QP. The combination of heating and HIUS can improve the digestibility, solubility and foam properties of AP. Conjugation through the Maillard reaction can improve BPI and QP interfacial properties. Thus, present study provides a review of the solubility, extraction and modification of the techno-functional properties of AP, BP and QP. © 2022 Society of Chemical Industry.


Asunto(s)
Chenopodium quinoa , Fagopyrum , Chenopodium quinoa/química , Fagopyrum/química , Semillas/química , Solubilidad , Agua/análisis
3.
J Sci Food Agric ; 102(11): 4640-4646, 2022 Aug 30.
Artículo en Inglés | MEDLINE | ID: mdl-35174497

RESUMEN

BACKGROUND: Tara gum (TG) is characterized by its high viscosity and medium solubility, which is a result of its high molecular mass. However, for many applications, these characteristics are undesirable, making the use of TG infeasible. The present study aimed to evaluate the effect of high-intensity ultrasound on the depolymerization of aqueous solutions of TG. The effect of ultrasonication was investigated by viscometry analysis as well as Fourier transform infrared spectroscopy (FTIR) and solubility. RESULTS: The intrinsic viscosity (η) and the molecular weight (Mw ) of TG decreased after ultrasound, achieving a molecular weight reduction of 13.50 × 105 g mol-1 after 60 min of sonication at 25 °C compared to 22.04 × 105 g mol-1 before treatment. Degradation kinetics were applied to estimate the rate constant of degradation (k). It was found that the k value of TG increased with increasing temperature from 25 to 55 °C. Partially hydrolyzed TG showed greater solubility at the two temperatures investigated (25 and 80 °C). Ultrasonic treatment did not change the chemical structure of the TG molecules according to the structural analysis by FTIR, confirming its action only as breaking the structure of the polymer. CONCLUSION: Ultrasound is a simple method for effectively reducing the molecular weight and viscosity and increasing the solubility of TG without using chemical reagents. The synthesis of partially hydrolyzed TG expands its potential for use in food products, including as a soluble dietary fiber. © 2022 Society of Chemical Industry.


Asunto(s)
Gomas de Plantas , Ultrasonido , Gomas de Plantas/química , Temperatura , Viscosidad , Agua/química
4.
J Am Chem Soc ; 143(9): 3481-3493, 2021 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-33621090

RESUMEN

This paper demonstrates that the molecular conformation (in addition to the composition and structure) of molecules making up self-assembled monolayers (SAMs) influences the rates of charge tunneling (CT) through them, in molecular junctions of the form AuTS/S(CH2)2CONR1R2//Ga2O3/EGaIn, where R1 and R2 are alkyl chains of different length. The lengths of chains R1 and R2 were selected to influence the conformations and conformational homogeneity of the molecules in the monolayer. The conformations of the molecules influence the thickness of the monolayer (i.e. tunneling barrier width) and their rectification ratios at ±1.0 V. When R1 = H, the molecules are well ordered and exist predominantly in trans-extended conformations. When R1 is an alkyl group (e.g., R1 ≠ H), however, their conformations can no longer be all-trans-extended, and the molecules adopt more gauche dihedral angles. This change in the type of conformation decreases the conformational order and influences the rates of tunneling. When R1 = R2, the rates of CT decrease (up to 6.3×), relative to rates of CT observed through SAMs having the same total chain lengths, or thicknesses, when R1 = H. When R1 ≠ H ≠ R2, there is a weaker correlation (relative to that when R1 = H or R1 = R2) between current density and chain length or monolayer thickness, and in some cases the rates of CT through SAMs made from molecules with different R2 groups are different, even when the thicknesses of the SAMs (as determined by XPS) are the same. These results indicate that the thickness of a monolayer composed of insulating, amide-containing alkanethiols does not solely determine the rate of CT, and rates of charge tunneling are influenced by the conformation of the molecules making up the junction.

5.
Trop Anim Health Prod ; 53(2): 226, 2021 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-33763711

RESUMEN

Cattle of Colombian creole breed Chino Santandereano in the raising phase were subjected to stabling for 100 days in order to determine the productive, nutritional, and metabolic capacity when exposed to different degrees of protein-energy supplementation. Sixteen whole males with an initial mean weight of 377.69 ± 16.55 kg were used in completely randomized delineation with four treatments and four repetitions per treatment, as follows: UNS, not supplemented; low, supplemented with amounts relative to 0.5% of body weight; medium, supplemented with amounts relative to 1.0% of the live weight; and high, supplemented with amounts relative to 1.5% of body weight. At the end of each experimental period, the animals were weighed, and samples of feed, feces, blood, and urine were collected to determine the performance, consumption, and digestibility of the nutritional components, and nitrogen balance. In the greater performance, consumption, and digestibility of DM, OM, C-NFCP, EE, and NFC, the concentration of ureic nitrogen in blood and urine (P <0.05) was observed in supplemented animals when contrasted with UNS. Bovine Chinese Santandereano presents high productive, nutritional, and metabolic potential as a response to high levels of protein-energy supplementation.


Asunto(s)
Alimentación Animal , Fenómenos Fisiológicos Nutricionales de los Animales , Alimentación Animal/análisis , Animales , Bovinos , Dieta , Suplementos Dietéticos , Digestión , Masculino , Nitrógeno
6.
J Food Sci Technol ; 58(7): 2773-2782, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34194111

RESUMEN

The influence of the concentration (5-20 mg/mL) of different cosolutes (sucrose and NaCl) on the rheological and thermal properties of concentrated Tara gum (TG) solutions (1.5-2.5% w/v) was investigated. Furthermore, the structural properties of the TG, TG-sucrose and TG-NaCl solutions were studied. The TG, TG-sucrose and TG-NaCl solutions exhibited a pseudoplastic and typical viscoelastic behavior of an entangled network structure. An increase in the TG concentration increased the pseudoplasticity and the elasticity of the solutions, while the incorporation of NaCl reduced these properties. Sucrose had little influence on the rheological properties of the TG solutions. The texture profile and the water holding capacity of the TG solutions were significantly influenced by the concentration of the TG and did not change with the addition of the cosolutes. The thermal stability of the TG solutions was reduced by NaCl and was not altered by sucrose. The microstructures of the TG solutions was significantly affected by NaCl, supporting the results obtained from rheological and thermal analyses. The results of this study may be useful for the formulation and processing of foods containing TG.

7.
Disasters ; 43(2): 410-430, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30516865

RESUMEN

Drills are an important element of disaster management, helping to increase preparedness and reduce the risk of real-time failure. Yet, they are not applied systematically to slow-onset disasters such as a drought, which causes damage that is not instantly apparent and thus does not solicit immediate action. This case study evaluates how drills inform institutional responses to slow-onset disasters. It spotlights Guatemala, a country where drought has severe impacts on livelihoods and the food security of small farmers. By implementing part of the Ministry of Agriculture, Livestock and Food's institutional response plan for drought, it explores how drills can help to detect issues in emergency response and to foster an institutional focus on improvements in preparedness. The results reveal that drills alone do not trigger institutional improvements if unsupported by a wider strategy that seeks to enhance capacities and protocols. These findings are valuable, however, in making problems transparent and in creating the space for discussion.


Asunto(s)
Agricultura/organización & administración , Planificación en Desastres/organización & administración , Sequías , Guatemala , Humanos
8.
Compr Rev Food Sci Food Saf ; 17(3): 792-805, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-33350131

RESUMEN

Whey proteins are obtained from dairy industry waste. Studies involving the analysis of the bioactive compounds in whey show health benefits, as it is an excellent source of indispensable amino acids. Milk whey contains principally ß-lactoglobulin, α-lactoglobulin, bovine serum albumin, and lactoferrin, proteins with innumerable functional and technological properties. One application of these proteins in food is the formation of interpolymer complexes, along with other proteins or anionic polysaccharides. The formation of complexes occurs mainly through electrostatic interactions between a negatively charged biopolymer and a positively charged biopolymer. This formation is influenced by factors such as pH, ionic strength, and biopolymer ratio. Because they do not use high temperatures and chemical reagents and have additional nutritional and functional value, these complexes have been used as encapsulating agents for bioactive ingredients. Recent studies on their training and applications are addressed in this review to boost new research and applications in the food industry, thus increasing opportunities for utilizing whey proteins.

9.
Crit Rev Food Sci Nutr ; 56(7): 1108-25, 2016 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-24824044

RESUMEN

The products formed by glycosylation of food proteins with carbohydrates via the Maillard reaction, also known as conjugates, are agents capable of changing and improving techno-functional characteristics of proteins. The Maillard reaction uses the covalent bond between a group of a reducing carbohydrates and an amino group of a protein. This reaction does not require additional chemicals as it occurs naturally under controlled conditions of temperature, time, pH, and moisture. Moreover, there is growing interest in modifying proteins for industrial food applications. This review analyses the current state of art of the Maillard reaction on food protein functionalities. It also discusses the influence of the Maillard reaction on the conditions and formulation of reagents that improve desirable techno-functional characteristics of food protein.


Asunto(s)
Proteínas en la Dieta/química , Alimentos , Reacción de Maillard , Polisacáridos/química , Fenómenos Químicos , Carbohidratos de la Dieta , Glicosilación , Calor
11.
Qual Life Res ; 24(8): 2039-44, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-25673437

RESUMEN

OBJECTIVE: To assess the validity and reliability of the chronic respiratory questionnaire (CRQ) in the measurement of HRQL in the Colombian population with COPD. STUDY DESIGN AND SETTING: A cross-sectional study was conducted with a sample of 200 patients diagnosed with COPD according to GOLD criteria. Convergence validity was evaluated by correlating the questionnaire results with other clinical variables such as exercise tolerance, forced expiratory volume at the first second (FEV1), and depression levels. RESULTS: HRQL measured through the CRQ correlated significantly with the 6-min walk test (r = 0.34), just as the dimensions fatigue (r = 0.37) and dyspnoea correlated with the FEV1 test (r = 0.21) and the dimensions emotional function and disease management with depression levels (r = -0.79). The Generalized Structured Component Analysis (GSCA) with the prespecified model is showed, and the total variance explained by the items in the model was 61.5 % (FIT = 0.615), unweighted least squares (GFI = 0.998), and standardised root mean square (SRMR = 0.084), indicating that the model fits adequately. CONCLUSION: The CRQ presents evidence of adequate validity and reliability in the Colombian population. Its use is recommended to measure HRQL in patients with COPD, although future validations will be needed to identify the property of sensitivity to change.


Asunto(s)
Estado de Salud , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Enfermedad Pulmonar Obstructiva Crónica/psicología , Calidad de Vida , Encuestas y Cuestionarios , Adulto , Anciano , Colombia , Estudios Transversales , Disnea/fisiopatología , Disnea/psicología , Emociones , Tolerancia al Ejercicio/fisiología , Fatiga , Femenino , Volumen Espiratorio Forzado , Hispánicos o Latinos , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Caminata
12.
Ecotoxicol Environ Saf ; 112: 132-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25463863

RESUMEN

Microcystin (MC) accumulation and depuration in environmentally exposed tilapia (Oreochromis niloticus) at a chronically contaminated eutrophic lagoon was studied. This is one of the scarce reports on microcystin accumulation in bile of environmentally exposed fish, and gonad MC accumulation in the field, in contrast to laboratory exposure experiments. Results show that preferential MC accumulation in the environment occurred in tilapia fish muscle, followed by gonads, liver and, finally, bile. Biliary MC excretion in in situ conditions indicates elimination from the body to a certain degree. High gonad MC bioaccumulation is of concern, since this could indicate potential reproductive problems in this species. This study also demonstrated that tilapia shows similar oxidative stress responses (in the form of reduced glutathione, GSH) in the environment as those observed in laboratory exposed fish. MC dietary intake values for tilapia muscle and liver were above the limits imposed by international legislations, indicating that the local human population should exercise care when ingesting this species as a part of their diet and that human ingestion of MC-contaminated samples should be carefully monitored.


Asunto(s)
Cíclidos/metabolismo , Exposición a Riesgos Ambientales , Glutatión/metabolismo , Microcistinas/toxicidad , Estrés Oxidativo/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Brasil , Monitoreo del Ambiente , Estuarios , Eutrofización , Microcistinas/análisis , Microcistinas/metabolismo , Distribución Tisular , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/metabolismo
13.
Microbiol Spectr ; 12(5): e0241823, 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38591917

RESUMEN

The tenacious biofilms formed by Streptococcus mutans are resistant to conventional antibiotics and current treatments. There is a growing need for novel therapeutics that selectively inhibit S. mutans biofilms while preserving the normal oral microenvironment. Previous studies have shown that increased levels of cyclic di-AMP, an important secondary messenger synthesized by diadenylate cyclase (DAC), favored biofilm formation in S. mutans. Thus, targeting S. mutans DAC is a novel strategy to inhibit S. mutans biofilms. We screened a small NCI library of natural products using a fluorescence detection assay. (+)-Brazilin, a tetracyclic homoisoflavanoid found in the heartwood of Caesalpinia sappan, was identified as one of the 11 "hits," with the greatest reduction (>99%) in fluorescence at 100 µM. The smDAC inhibitory profiles of the 11 "hits" established by a quantitative high-performance liquid chromatography assay revealed that (+)-brazilin had the most enzymatic inhibitory activity (87% at 100 µM) and was further studied to determine its half maximal inhibitory concentration (IC50 = 25.1 ± 0.98 µM). (+)-Brazilin non-competitively inhibits smDAC's enzymatic activity (Ki = 140.0 ± 27.13 µM), as determined by a steady-state Michaelis-Menten kinetics assay. In addition, (+)-brazilin's binding profile with smDAC (Kd = 11.87 µM) was illustrated by a tyrosine intrinsic fluorescence quenching assay. Furthermore, at low micromolar concentrations, (+)-brazilin selectively inhibited the biofilm of S. mutans (IC50 = 21.0 ± 0.60 µM) and other oral bacteria. S. mutans biofilms were inhibited by a factor of 105 in colony-forming units when treated with 50 µM (+)-brazilin. In addition, a significant dose-dependent reduction in extracellular DNA and glucan levels was evident by fluorescence microscopy imaging of S. mutans biofilms exposed to different concentrations of (+)-brazilin. Furthermore, colonization of S. mutans on a representative model of enamel using suspended hydroxyapatite discs showed a >90% reduction with 50 µM (+)-brazilin. In summary, we have identified a drug-like natural product inhibitor of S. mutans biofilm that not only binds to smDAC but can also inhibit the function of smDAC. (+)-Brazilin could be a good candidate for further development as a potent therapeutic for the prevention and treatment of dental caries.IMPORTANCEThis study represents a significant advancement in our understanding of potential therapeutic options for combating cariogenic biofilms produced by Streptococcus mutans. The research delves into the use of (+)-brazilin, a natural product, as a potent inhibitor of Streptococcus mutans' diadenylate cyclase (smDAC), an enzyme crucial in the formation of biofilms. The study establishes (+)-brazilin as a non-competitive inhibitor of smDAC while providing initial insights into its binding mechanism. What makes this finding even more promising is that (+)-brazilin does not limit its inhibitory effects to S. mutans alone. Instead, it demonstrates efficacy in hindering biofilms in other oral bacteria as well. The broader spectrum of anti-biofilm activity suggests that (+)-brazilin could potentially serve as a versatile tool in a natural product-based treatment for combating a range of conditions caused by resilient biofilms.


Asunto(s)
Antibacterianos , Biopelículas , Isoflavonas , Streptococcus mutans , Biopelículas/efectos de los fármacos , Streptococcus mutans/efectos de los fármacos , Streptococcus mutans/enzimología , Isoflavonas/farmacología , Isoflavonas/metabolismo , Isoflavonas/química , Antibacterianos/farmacología , Antibacterianos/química , Productos Biológicos/farmacología , Productos Biológicos/química , Pruebas de Sensibilidad Microbiana , Liasas de Fósforo-Oxígeno/metabolismo , Proteínas Bacterianas/metabolismo , Proteínas Bacterianas/genética , Humanos
14.
J Med Chem ; 66(12): 7909-7925, 2023 06 22.
Artículo en Inglés | MEDLINE | ID: mdl-37285134

RESUMEN

We designed and synthesized analogues of a previously identified biofilm inhibitor IIIC5 to improve solubility, retain inhibitory activities, and to facilitate encapsulation into pH-responsive hydrogel microparticles. The optimized lead compound HA5 showed improved solubility of 120.09 µg/mL, inhibited Streptococcus mutans biofilm with an IC50 value of 6.42 µM, and did not affect the growth of oral commensal species up to a 15-fold higher concentration. The cocrystal structure of HA5 with GtfB catalytic domain determined at 2.35 Å resolution revealed its active site interactions. The ability of HA5 to inhibit S. mutans Gtfs and to reduce glucan production has been demonstrated. The hydrogel-encapsulated biofilm inhibitor (HEBI), generated by encapsulating HA5 in hydrogel, selectively inhibited S. mutans biofilms like HA5. Treatment of S. mutans-infected rats with HA5 or HEBI resulted in a significant reduction in buccal, sulcal, and proximal dental caries compared to untreated, infected rats.


Asunto(s)
Caries Dental , Streptococcus mutans , Ratas , Animales , Hidrogeles , Caries Dental/tratamiento farmacológico , Biopelículas
15.
AIDS Educ Prev ; 35(5): 390-405, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37843908

RESUMEN

We explored whether siblings can be engaged in PrEP promotion. We used the Information-Motivation-Behavior model to develop and conduct surveys and dyadic interviews with Latino men who have sex with men (LMSM) and their siblings (n = 31) and three sibling-only focus groups (n = 20). For LMSM, only n = 14 (45%) agreed they would benefit from taking PrEP, yet n = 22 (71%) would take PrEP to make their sibling worry less about them, and n = 23 (74%) requested a PrEP referral. For siblings, n = 20 (65%) believed PrEP would benefit their brother, and n = 19 (95%) in the focus groups said they would take PrEP to help their brother get started. Qualitative results include (1) siblings' support for PrEP use, (2) explicit conversations about sex were not necessary for discussing sexual health, and (3) siblings wanted to understand what they could do to encourage their brother to consider PrEP. We conclude siblings can be engaged in PrEP promotion.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Profilaxis Pre-Exposición , Minorías Sexuales y de Género , Hermanos , Humanos , Masculino , Fármacos Anti-VIH/uso terapéutico , Estudios de Factibilidad , Hispánicos o Latinos , Infecciones por VIH/prevención & control , Homosexualidad Masculina , Profilaxis Pre-Exposición/métodos
16.
Int J Biol Macromol ; 253(Pt 6): 127148, 2023 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-37832622

RESUMEN

This study assessed the technological feasibility of microencapsulating vitamin C (VC) via coacervation between yeast cells (YC) and xanthan gum (XG). The interaction efficiency between YC and XG was examined across various pHs and ratios, while characterizing the microcapsules in terms of encapsulation efficiency, particle size, and thermal and chemical stability. Additionally, in vitro digestion experiments were conducted to determine the digestion efficiency and bioavailability of the bioactive compound. The optimally produced microcapsules exhibited favorable functional attributes, including low water activity (≤ 0.3) and particle size (≤ 33.52 µm), coupled with a high encapsulation efficiency (∼ 86.12 %). The microcapsules were able to increase the stability of VC at high temperatures and during storage when compared to the control. The in vitro experiment revealed that the microcapsules effectively retained approximately 50 % of the VC in simulated gastric fluid, with up to 80 % released in simulated intestinal fluid. However, due to prior degradation in the simulated gastric fluid, the achieved bioavailability was around 68 %. These results are promising, underscoring the potential of these microcapsules as a viable technology for encapsulating, protect, and releasing water-soluble bioactives in the GI tract.


Asunto(s)
Saccharomyces cerevisiae , Agua , Emulsiones/química , Cápsulas/química
17.
Curr Res Food Sci ; 5: 718-725, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35497774

RESUMEN

Iron deficiency is one of the main causes of anemia in the world, especially in children and women, so food fortification through microencapsulation is a viable alternative to combat this deficiency. The present work aimed to encapsulate iron in a water-in-oil-in-water double emulsion (W1/O/W2), which was formed with whey protein isolate and polyglycerol polyricinoleate as the emulsifying agents, tara gum as a thickening agent, and sucrose as an osmotic active substance. The double emulsion formed with 12% whey protein isolate, 0.8% tara gum, and 2% sucrose presented high encapsulation efficiency (96.95 ± 1.00%) and good stability (up to 7 days). Additionally, after the in vitro gastrointestinal simulations, the bioaccessibility was high for adults (49.54 ± 5.50%) and infants (39.71 ± 2.33%). Finally, the study show that double emulsions can form stable systems with high iron bioaccessibility even in infant gastric systems, which indicates the possibility of using double emulsions to fortify food with iron.

18.
Food Chem ; 343: 128529, 2021 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-33191011

RESUMEN

Vitamin D3 plays a fundamental role in human health; however, it is highly susceptible to environmental conditions and the gastrointestinal tract. In this study, complex coacervates obtained from gelatin A and carboxymethyl tara gum (CMTG) were used as wall materials for the encapsulation of vitamin D3 (VD3). Zeta potential and turbidity measurements were employed to optimize the pH and ratio (gelatin A:CMTG), and the results showed that the ideal conditions for the complex coacervation were pH 4.0 and a 6:1 ratio. The encapsulation efficiency (EE) was determined as a function of the total concentration of biopolymers (TC%) and the core-to-wall ratio, and the greatest EE (80%) was achieved at a TC of 1% and a ratio of 1:2; spherical particles with an average size of 0.25 µm were obtained. The microencapsulation increased the thermal stability of VD3, and FTIR confirmed the presence of the biopolymers and VD3 in the capsules. An in vitro simulation showed a more pronounced release in the small intestine with a vitamin bioaccessibility of 56%. The encapsulation of bioactive lipophilic compounds by complex coacervates of gelatin A and CMTG resulted in improved stability and prolonged release during digestion.


Asunto(s)
Colecalciferol/química , Gelatina/química , Gomas de Plantas/química , Cápsulas , Humanos
19.
Int J Biol Macromol ; 160: 861-870, 2020 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-32497672

RESUMEN

This study evaluated the most appropriate conditions (pH and biopolymers ratio) for the formation of the complex between ß-lactoglobulin (ß-lg) and sodium alginate (NaAlg). Furthermore, we microencapsulated black pepper essential oil (EO) using these biopolymers and transglutaminase as a cross-linking agent, and stability during in vitro digestion and its release in food models were studied. A ratio of 17:1 (ß-lg/NaAlg) at a pH of 4.5 was the optimal condition for the formation of the complex. The encapsulation efficiency (85.01% ± 0.26) and chemical and morphological characteristics suggested that black pepper EO was microencapsulated using polymers and cross-linking agent naturals. The particle size demonstrated that the capsules produced were on micro scale. The black pepper EO microcapsules lost lower release in water, and the Rigger-Peppas model indicated that the Fickian diffusion mechanism occurred. The microcapsules demonstrated a low release of black pepper EO during oral and gastric digestion and a higher release in intestinal digestion. The black pepper EO after digestion presented high stability (84.8% ± 0.07), and bioaccessibility (31.16% ± 0.3). The results suggest that the black pepper EO was microencapsulated and, preserved in aqueous food model and during oral and gastric conditions tested in vitro.


Asunto(s)
Alginatos/química , Composición de Medicamentos , Lactoglobulinas/química , Aceites Volátiles/química , Aceites Volátiles/farmacología , Piper nigrum/química , Biopolímeros/química , Calorimetría , Cápsulas , Digestión , Estabilidad de Medicamentos , Vaciamiento Gástrico/efectos de los fármacos , Fármacos Gastrointestinales/química , Fármacos Gastrointestinales/farmacología , Concentración de Iones de Hidrógeno , Tamaño de la Partícula , Espectroscopía Infrarroja por Transformada de Fourier
20.
Food Chem ; 316: 126345, 2020 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-32045817

RESUMEN

Black pepper essential oil (EO) was encapsulated by complex coacervation with lactoferrin and sodium alginate using transglutaminase as a cross-linking agent. The encapsulation efficiency varied from 31.66 to 84.48%. Chemical and morphological characteristics suggest that the EO was encapsulated in a lactoferrin/sodium alginate shell. The chemical composition of the encapsulated EO was identified by gas chromatography (GC) and nuclear magnetic resonance (NMR). The GC and NMR analyses indicated good core protection with the materials used. The stability of the black pepper EO capsules under in vitro digestion was evaluated. Theses capsules demonstrated the low release of the EO during gastric digestion and higher release in intestinal digestion. These results suggest that these capsules can be used to transport active ingredients and that they are resistant to oral and gastric conditions that were tested in vitro.


Asunto(s)
Alginatos/química , Lactoferrina/química , Aceites Volátiles/química , Piper nigrum/química , Cápsulas/química , Cromatografía de Gases
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