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2.
Rev. méd. Panamá ; 42(3): 15-19, dic 2022.
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1413295

RESUMEN

Introducción: El síndrome de insensibilidad androgénica es un desorden genético y un tipo de trastorno del desarrollo sexual. Es la feminización de los genitales externos evaluados al nacimiento cuando el genotipo es 46, XY. Objetivo: Presentar la clínica, estudios moleculares, ultrasonidos durante el embarazo y del recién nacido con trastorno de diferenciación sexual. Caso Clínico: Femenina de 35 años con tercer embarazo, feto único, con resultado de cribado genético prenatal no invasivo ampliado de aneuploidías cromosómicas y determinación del sexo fetal a la semana 11 de gestación con sexo genético masculino, ultrasonido con ángulo del tubérculo genital de menos de 30° indicativo de sexo fenotípico femenino y ecografía postnatal con sexo gonadal masculino. Panel molecular genético con una variante patogénica para el Gen AR, en hemicigosis, asociado a Síndrome de Insensibilidad Androgénica. Conclusión: La discordancia sexual fenotipo-genotipo puede indicar una condición genética, cromosómica o bioquímica subyacente. El manejo conjunto interdisciplinario y el consejo genético permite el diagnóstico molecular neonatal temprano de la condición. (provisto por Infomedic International)


Introduction: Androgen insensitivity syndrome is a genetic disorder and a type of sexual development disorder. It is characterized by the evident feminization of the external genitalia at birth in an individual with the 46, XY genotype. Aim: To present the clinic, molecular studies, obstetric ultrasonography of the first trimester and ultrasound of the newborn with sexual differentiation disorder. Clinic case: 35-year-old female with third pregnancy, singleton fetus, with extended non-invasive prenatal genetic screening for chromosomal aneuploidies and fetal sex determination at week 11 of gestation with male genetic sex, ultrasound with genital tubercle angle less than 30° indicative of female phenotypic sex and postnatal ultrasound with male gonadal sex. Genetic molecular panel with a pathogenic variant for the AR gene, in hemi zygosis. Conclusion: Early detection of phenotype-genotype sexual discordance is important as it may indicate an underlying genetic, chromosomal, or biochemical condition, allowing timely critical counseling and postnatal treatment. (provided by Infomedic International)

3.
Food Chem X ; 13: 100247, 2022 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-35499029

RESUMEN

The objective of this work was to obtain hydrolysates and peptide fractions from pork (PSC) and chicken (CSC) skin collagen extracts and to evaluate their ability as pancreatic lipase inhibitors. Collagen extracts were hydrolyzed with collagenase or a protease from Bacillus licheniformis (MPRO NX®) at 6, 12, and 24 h. After 24 h incubation, the highest degree of hydrolysis of PSC (p < 0.05) was obtained with collagenase (72.58%), while in CSC was obtained with MPRO NX® (64.45%). Hydrolysates obtained at 24 h had the highest inhibitory activity of lipase (p < 0.05). CSC/collagenase hydrolysates (10 mg/mL) presented the highest inhibitory activity (75.53%) (p < 0.05). Ultrafiltrated fractions >5 kDa from CSC/collagenase and PSC/MPRO NX® hydrolysates were the most bioactive fractions (IC50: 4.33 mg/mL). The highest were obtained by CSC peptides (IC50s: 6.30 and 6.08 mg/mL). These results may be considered as a novel approach to use collagen hydrolysates, or their peptide fractions, as promising natural inhibitors of pancreatic lipase.

4.
Molecules ; 26(7)2021 Apr 06.
Artículo en Inglés | MEDLINE | ID: mdl-33917637

RESUMEN

The majority of snacks expanded by extrusion (SEE) are made with vegetable sources, to improve their nutritional content; it has been proposed to incorporate squid (Dosidicus gigas), due to its high protein content, low price and high availability. However, the interaction of proteins of animal origin with starch during extrusion causes negative effects on the sensory properties of SEE, so it is necessary to know the type of protein-carbohydrate interactions and their effect on these properties. The objective of this research was to study the interaction of proteins and carbohydrates of SEE elaborated with squid mantle, potato and corn. The nutritional composition and protein digestibility were evaluated, Fourier transform infrared (FTIR) and Differential Scanning Calorimetry (DSC) were used to study the formation of protein-starch complexes and the possible regions responsible for their interactions. The SEE had a high protein content (40-85%) and biological value (>93%). The melting temperature (Tm) was found between 145 and 225 °C; the Tm values in extruded samples are directly proportional to the squid content. The extrusion process reduced the amine groups I and II responsible for the protein-protein interaction and increased the O-glucosidic bonds, so these bonds could be responsible for the protein-carbohydrate interactions.


Asunto(s)
Rastreo Diferencial de Calorimetría , Decapodiformes/química , Proteínas/química , Bocadillos , Solanum tuberosum/química , Almidón/química , Animales , Espectroscopía Infrarroja por Transformada de Fourier
5.
Probiotics Antimicrob Proteins ; 13(4): 1033-1043, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-33512646

RESUMEN

Studies have shown that the intracellular content of probiotic (postbiotics) has antioxidant properties, which can improve the antioxidant status in vivo. However, its absorption and mechanisms underlying the protective effects are still unknown. The antioxidant capacity of Lacticaseibacillus casei CRL431 (IC-431) postbiotics was determined after an in vitro simulated digestive process. Permeability of antioxidant constituents of IC-431 was determined by an ex vivo everted duodenum assay. Aflatoxin B1-induced oxidative stress rat models were established and treated with IC-431; biomarkers of hepatic mitochondrial function and H2O2 levels, oxidative stress, and oxidative stress index (OSi) were examined. The antioxidant capacity of IC-431 (477 ± 45.25 µmol Trolox Equivalent/L) was reduced by exposure to the simulated digestive process. No difference (p > 0.05) was found among digested and the permeate fraction of IC-431. A protective effect was observed by significantly lower OSi and higher liver glutathione peroxidase and catalase activities. Lower H2O2 production, a higher degree of mitochondrial uncoupling, and lower mitochondrial respiration coefficient were also observed (p < 0.05). These results suggest that IC-431 antioxidant components permeate intestinal barriers to enter the bloodstream and regulate antioxidant status during AFB1-induced oxidative stress by reducing hepatic mitochondrial dysfunction, thus enhancing antioxidant enzyme response.


Asunto(s)
Aflatoxina B1 , Lacticaseibacillus casei , Mitocondrias , Estrés Oxidativo , Probióticos , Aflatoxina B1/toxicidad , Animales , Antioxidantes , Peróxido de Hidrógeno , Mitocondrias/fisiología , Ratas
6.
Appl Biochem Biotechnol ; 193(2): 389-404, 2021 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33009584

RESUMEN

Proteolytic enzymes are widely distributed in nature, playing essential roles in important biological functions. Recently, the use of plant proteases at the industrial level has mainly increased in the food industry (e.g., cheesemaking, meat tenderizing, and protein hydrolysate production). Current technological and scientific advances in the detection and characterization of proteolytic enzymes have encouraged the search for new natural sources. Thus, this work aimed to explore the milk-clotting and proteolytic properties of different tissues of Vallesia glabra. Aqueous extracts from the leaves, fruits, and seeds of V. glabra presented different protein profiles, proteolytic activity, and milk-clotting activity. The milk-clotting activity increased with temperature (30-65 °C), but this activity was higher in leaf (0.20 MCU/mL) compared with that in fruit and seed extracts (0.12 and 0.11 MCU/mL, respectively) at 50 °C. Proteolytic activity in the extracts assayed at different pH (2.5-12.0) suggested the presence of different types of active proteases, with maximum activity at acidic conditions (4.0-4.5). Inhibitory studies indicated that major activity in V. glabra extracts is related to cysteine proteases; however, the presence of serine, aspartic, and metalloproteases was also evident. The hydrolytic profile of caseins indicated that V. glabra leaves could be used as a rennet substitute in cheesemaking, representing a new and promising source of proteolytic enzymes.


Asunto(s)
Apocynaceae/enzimología , Leche/química , Péptido Hidrolasas/química , Hojas de la Planta/enzimología , Proteínas de Plantas/química , Proteolisis , Semillas/enzimología , Animales , Concentración de Iones de Hidrógeno
7.
J Dairy Sci ; 103(1): 242-253, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31733845

RESUMEN

Lactococcus lactis is the lactic acid bacteria most frequently used for the production of cheese starter cultures, mainly because of their efficient production of aroma compounds. However, commercial cultures do not always produce the typical aroma notes of artisanal raw-milk cheeses. Thus, the objective of this study was to characterize the volatile compounds generated by wild L. lactis strains in Mexican Fresco cheese made with pasteurized milk. Four strains of wild L. lactis were evaluated for their aroma production in Mexican Fresco cheese using sensory and instrumental analysis. The aroma profiles were evaluated by descriptive sensory analysis. Volatiles were determined by solid-phase microextraction and gas chromatography-mass spectrometry. Principal component analysis was applied to interpret analytical and sensory data. Mexican Fresco cheese aroma was described as milkfat, yogurt, yeasty, barny, dirty socks, and Fresco cheese. Cheese with L. lactis strains R7 or B7 were most similar to commercial raw milk Fresco cheese in all aroma descriptors. Volatiles identified in all cheeses were esters, acids, alcohols, ketones, and aldehydes, but the main differences were found for total volatile relative abundance. Also, volatile concentrations (µg/g) in commercial raw milk Fresco cheese and cheeses made with L. lactis R7 or B7 were 4 methyl esters [C4 (4.15 vs. 5.47-13.74), C6 (0.12 vs. 1.53-15.34), C8 (1.06 vs. 0.32-6.65), and C10 (0.62 vs. 0.41-3.74)], 7 acids [C4 (1.92 vs. 0.30-9.29), C6-C10 (0.05-4.48 vs. 0.11-30.45), and C12 (0.13 vs. 0.28-0.30)], 2 alcohols [(3-methyl-1-butanol (3.48 vs. 3.4-13.13) and phenylethyl alcohol (0.10 vs. 0.63-2.04)], and 1 ketone (acetoin; 1.22 vs. 0.28-0.99). The first 3 principal components explained 78.2% of the total variation and clearly distinguished 3 main groups. Cheese made with L. lactis R7 was classified in the same group as key compounds associated with Fresco cheese aroma and show potential as a starter in Mexican Fresco cheese manufacture.


Asunto(s)
Queso/análisis , Lactococcus lactis/química , Odorantes/análisis , Cromatografía de Gases y Espectrometría de Masas , México , Análisis Multivariante , Microextracción en Fase Sólida , Especificidad de la Especie
8.
CienciaUAT ; 14(1): 133-144, jul.-dic. 2019. graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1124376

RESUMEN

Resumen El lactosuero posee una gran cantidad de los componentes de la leche, sin embargo, una alta proporción del volumen generado se sigue tirando, provocando pérdida de nutrientes y problemas de contaminación. El objetivo del presente trabajo fue proveer información sobre las propiedades nutricionales, funcionales y biológicas del lactosuero, generado por la industria quesera artesanal, así como evidencias científicas recientes que sustentan, bajo distintos enfoques tecnológicos, el potencial de aprovechamiento, mediante su transformación o recuperación para adicionarle valor. Las oportunidades en la valorización del lactosuero, a través de la elaboración de diversos productos lácteos, como el requesón (queso de suero), bebidas fermentadas o con frutas, bebidas para deportistas, bebidas alcohólicas, mantequilla de suero, dulces, helados y paletas, reflejan el nicho de oportunidades para hacer la industria quesera artesanal más redituable. El cambio de paradigmas en los productores artesanales, en percibir al lactosuero como una fuente de co-productos para su recuperación, transformación y reincorporación a sus procesos, acorde a las capacidades tecnológicas de dicha industria, y no como un subproducto, reduciría las pérdidas de componentes de alto valor (e.g., proteína, lípidos y azúcares), trayendo consigo efectos benéficos, tanto ambientales como económicos.


Abstract Whey contains a high concentration of milk components. However, a high volume of it continues to be discarded to the environment, leading to a loss in nutrients and pollution problems. The objective of the present review is oriented to provide information on the nutritional, functional and biological properties of the whey generated by the artisanal cheese idustry. Furthermore, scientific evidence supporting the different opportunities for its valorization, revised under different technological approaches is included. The potential of whey valorization, through its recovery or transformation into value-added products, includes its use in a diversity of food products. Whey use includes the production of requesón (whey cheese), fermented beverages, fruit-flavored drinks, sports drinks, alcoholic beverages, whey buttermilk, ice-cream, candies and popsicles. The transformation of whey produced by the artisanal cheese industry, offer a niche of opportunities to make this industry more profitable. The reduction in loss of highly valuable components (e.g., protein, fat and lactose) by using whey, according to their technological capabilities, represents a suitable option to its valorization, by changing the perception of whey as a waste, but as a source of co-products. The recovery, transformation and reincorporation into the processes, would bring beneficial economic effects to artisanal producers and reduce the environmental impact caused by this industry.

9.
Nutrients ; 11(9)2019 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-31505734

RESUMEN

Milk fermented with specific lactic acid bacteria (LAB) was reported to be a rich source of metabolites, such as peptides with different biological activities that may have a positive effect on cardiovascular health. Thus, in this study, the antithrombotic and hypocholesterolemic activities of fermented milk with specific strains of Lactococcus lactis were investigated before and after exposure to a simulated gastrointestinal digestion (SGD) model. The inhibition of thrombin-induced fibrin polymerization (IC50 peptide concentration necessary to inhibit thrombin activity by 50%), anticoagulant activity, inhibition of micellar solubility of cholesterol and bile acid binding capacity of water soluble fractions (WSF) <3 kDa from fermented milk were evaluated. Results indicated that the WSF from fermented milk with Lc-572 showed antithrombotic (IC50 = 0.049 mg/mL) and hypocholesterolemic (55% inhibition of micellar solubility of cholesterol and 27% bile acid binding capacity) activities. Meanwhile, fermented milk with Lc-571 showed mainly antithrombotic activity (IC50 = 0.045 mg/mL). On the other hand, fermented milk with Lc-600 presented mainly hypocholesterolemic activity (31.4% inhibition of micellar solubility of and 70% bile acid binding capacity). Moreover, biological activities were not lost after simulated gastrointestinal digestion conditions. Thus, fermented milk with these specific L. lactis strains show potential for the development of functional foods.


Asunto(s)
Anticolesterolemiantes/administración & dosificación , Fermentación , Fibrinolíticos/administración & dosificación , Lactococcus lactis/metabolismo , Leche/metabolismo , Animales , Ácidos y Sales Biliares/metabolismo , Colesterol/metabolismo , Digestión , Humanos , Leche/química , Leche/microbiología , Unión Proteica
10.
Food Technol Biotechnol ; 55(3): 398-404, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29089853

RESUMEN

Jumbo squid (Dosidicus gigas) muscle proteins show low functionality with limited use in gel products. This work aims to assess the influence of adding the natural and commercially available fibre, amidated low-methoxyl pectin (at 0.5, 1.0, 1.5, 2.0 and 3.0%), on the physicochemical and functional characteristics of jumbo squid (Dosidicus gigas) mantle muscle gels. The addition of 0.5% fibre showed an immediate effect on the gel texture profile analysis, improving hardness (p<0.05) from (3.4±0.7) N of the control (no added fibre) to (5.2±0.9) N, and increasing elasticity (p≥0.05). Shear force was significant only at 3.0% fibre addition. Water holding capacity also improved (p<0.05) with fibre addition (from 75% in the control to 90-95% after the treatments). Whiteness was affected (p<0.05) when 3.0% fibre was added. Differential scanning calorimetry showed two endothermic transition peaks in the gels. The second peak (actin) increased (p<0.05) by 1-2 °C with fibre addition. Therefore, the present study demonstrates that amidated low-methoxyl pectin (0.5-3.0%) is an excellent ingredient to improve jumbo squid mantle muscle protein functionality, increasing the gel texture and water retention characteristics.

11.
Appl Biochem Biotechnol ; 182(1): 181-196, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27830465

RESUMEN

Plant proteases are capable of performing several functions in biological systems, and their use is attractive for biotechnological process due to their interesting catalytic properties. Bromelia pinguin (aguama) is a wild abundant natural resource in several regions of Central America and the Caribbean Islands but is underutilized. Their fruits are rich in proteases with properties that are still unknown, but they represent an attractive source of enzymes for biotechnological applications. Thus, the proteolytic activity in enzymatic crude extracts (CEs) from wild B. pinguin fruits was partially characterized. Enzymes in CEs showed high proteolytic activity at acid (pH 2.0-4.0) and neutral alkaline (pH 7.0-9.0) conditions, indicating that different types of active proteases are present. Proteolytic activity inhibition by the use of specific protease inhibitors indicated that aspartic, cysteine, and serine proteases are the main types of proteases present in CEs. Activity at pH 3.0 was stable in a broad range of temperatures (25-50 °C) and retained its activity in the presence of surfactants (SDS, Tween-80), reducing agents (DTT, 2-mercapoethanol), and organic solvents (methanol, ethanol, acetone, 2-propanol), which suggests that B. pinguin proteases are potential candidates for their application in brewing, detergent, and pharmaceutical industries.


Asunto(s)
Proteasas de Ácido Aspártico/química , Bromelia/enzimología , Proteasas de Cisteína/química , Frutas/enzimología , Proteínas de Plantas/química , Serina Proteasas/química , Proteasas de Ácido Aspártico/antagonistas & inhibidores , Proteasas de Ácido Aspártico/aislamiento & purificación , Bromelia/química , Proteasas de Cisteína/aislamiento & purificación , Ditiotreitol/química , Pruebas de Enzimas , Frutas/química , Concentración de Iones de Hidrógeno , Cinética , Mercaptoetanol/química , Extractos Vegetales/química , Proteínas de Plantas/antagonistas & inhibidores , Proteínas de Plantas/aislamiento & purificación , Polisorbatos/química , Inhibidores de Proteasas/química , Proteolisis , Serina Proteasas/aislamiento & purificación , Dodecil Sulfato de Sodio/química , Solventes/química
12.
Braz. arch. biol. technol ; Braz. arch. biol. technol;56(6): 1002-1010, Nov.-Dec. 2013. graf, tab
Artículo en Inglés | LILACS | ID: lil-696946

RESUMEN

The aim of the present study was to produce fish silage by lactic acid fermentation and evaluate its use in feeding of quails (Coturnix coturnix japonica). An oven-dried mixture of fish silage and soybean meal (1:1 w/w) was used to prepare the diets with different levels of inclusion (0, 10, 20 and 30%) and evaluate its effect on the performance and meat quality of 160 quails. The inclusion level did not affect the growth and feed conversion ratio. The carcass yield (70.3%) and sensory quality of breast meat were not significantly different among the treatments (p>0.05). However, the concentration of unsaturated fatty acids such as oleic (C18:1n9C), linoleic (C18:2n6C), linolenic (C18:3n3), arachidonic (C20:4n6), cis eicosapentaenoic (C20:5n3) and cis docosahexaenoic (C22:6n3) increased in quail breast meat with the inclusion of fish silage:soybean mixture in the diet (p<0.05). Fish silage and its use in quail diets could offer a good alternative for fish waste utilization as feedstuff component for the improvement of fatty acid composition in its breast meat.

13.
Food Chem ; 141(3): 1902-7, 2013 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23870908

RESUMEN

Several proteases from plant sources have been proposed as milk coagulants, however, limited research has been done on their milk-clotting properties. The effect of temperature on the milk-clotting activity of kiwi fruit, melon and ginger extracts was evaluated, as well as the effects of the different extracts on curd properties. Melon extracts showed high milk-clotting activity over a broad temperature range (45-75 °C) while kiwi fruit and ginger extracts showed high activity over a narrower temperature range, with a maximum at 40 and 63 °C, respectively. Curds produced using kiwi extracts had textural properties comparable with those obtained using commercial rennet, while melon extracts produced a fragile gel and low curd yield. The milk-clotting behavior of the three plant extracts was related to the protease specificity present in these extracts. The kiwi proteases displayed chymosin-like properties and thus hold the best potential for use as a milk coagulant in cheese production.


Asunto(s)
Actinidia/química , Queso/análisis , Cucurbitaceae/química , Aditivos Alimentarios/química , Leche/química , Extractos Vegetales/química , Zingiber officinale/química , Animales , Bovinos , Concentración de Iones de Hidrógeno , Temperatura
14.
Phytochemistry ; 71(5-6): 515-23, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20079503

RESUMEN

Aspartic proteinases (APs) are involved in several physiological processes in plants, including protein processing, senescence, and stress response and share many structural and functional features with mammalian and microbial APs. The heterodimeric aspartic proteinase A1 from Arabidopsis thaliana (AtAP A1) was the first acid protease identified in this model plant, however, little information exists regarding its structure function characteristics. Circular dichroism analysis indicated that recombinant AtAP A1 contained an higher alpha-helical content than most APs which was attributed to the presence of a sequence known as the plant specific insert in the mature enzyme. rAtAP A1 was stable over a broad pH range (pH 3-8) with the highest stability at pH 5-6, where 70-80% of the activity was retained after 1 month at 37 degrees C. Using calorimetry, a melting point of 79.6 degrees C was observed at pH 5.3. Cleavage profiles of insulin beta-chain indicated that the enzyme exhibited a higher specificity as compared to other plant APs, with a high preference for the Leu(15)-Tyr(16) peptide bond. Molecular modeling of AtAP A1 indicated that exposed histidine residues and their interaction with nearby charged groups may explain the pH stability of rAtAP A1.


Asunto(s)
Proteínas de Arabidopsis/química , Arabidopsis/enzimología , Ácido Aspártico Endopeptidasas/química , Proteínas Recombinantes/química , Arabidopsis/química , Proteínas de Arabidopsis/farmacocinética , Ácido Aspártico Endopeptidasas/farmacocinética , Proteasas de Ácido Aspártico/química , Dicroismo Circular , Concentración de Iones de Hidrógeno , Hidrólisis , Modelos Moleculares , Conformación Proteica , Relación Estructura-Actividad , Especificidad por Sustrato
15.
Food Chem ; 109(4): 782-9, 2008 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-26049991

RESUMEN

Pacific whiting (Merluccius productus) muscle was used to produce hydrolysates with 10%, 15% and 20% degree of hydrolysis (DH) using the commercial protease Alcalase(®) and were characterized at pH 4.0, 7.0 and 10 according their solubility, emulsifying and foaming properties. Protein recovered in soluble fractions increased proportionally with the hydrolytic process, yielded 48.6±1.9, 58.6±4.1 and 67.8±1.4 of total protein after 10%, 15% and 20% DH, respectively. Freeze-dried hydrolysates presented almost 100% solubility (p>0.05) at the different pHs evaluated. Emulsifying properties (EC, EAI and ESI) were not affected by DH as most samples showed similar (p>0.05) results. Higher EC (p⩽0.05) than sodium caseinate, used as control, were obtained at pH 4 for most hydrolysates. Hydrolysates showed very low foaming capacity not affected by pH; but foam stability was equal or even better (p>0.05) than bovine serum albumin (BSA), except at pH 4.0. Results suggest that hydrolysates from Pacific whiting muscle can be produced with similar or better functional properties than the food ingredients used as standards.

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