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1.
Int J Mol Sci ; 24(2)2023 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-36674522

RESUMEN

The need for new non-animal and non-petroleum-based materials is strongly emphasized in the sustainable and green economy. Waste materials have proven a valuable resource in this regard. In fact, there have been quite a large number of goods obtained from wastes called "Vegan leather" that have gained the clothing market's attention in recent years. In practice, they are mostly composites of waste materials like cactus, pineapples, or, eventually, apples with polymers like polyurethane or polyvinyl chloride. The article presents the results of work aimed at obtaining a material based entirely on natural, biodegradable raw materials. Bacterial cellulose produced as a byproduct of the fermentation carried out by SCOBY was modified with glycerol and then altered by the entrapment of apple powder. The effect of introducing apple powder into the SCOBY culture media on the mechanical properties of the obtained bacterial cellulose was also evaluated The resulting material acquired new mechanical characteristics that are advantageous in terms of strength. Microscopic observation of the apple powder layer showed that the coverage was uniform. Different amounts of apple powder were used to cover the cellulose surface from 10 to 60%, and it was found that the variant with 40% of this powder was the most favorable in terms of mechanical strength. Also, the application of the created material as a card folder showed that it is durable in use and retains its functional characteristics for at least 1 month. The mechanical properties of modified bacterial cellulose were favorably affected by the entrapment of apple powder on its surface, and as a result, a novel material with functional characteristics was obtained.


Asunto(s)
Materiales Biocompatibles , Malus , Polvos , Celulosa/ultraestructura , Polímeros
2.
Materials (Basel) ; 13(21)2020 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-33158296

RESUMEN

Waste biomass can be used as an alternative source of energy. However, such use requires prior treatment of the material. This paper describes the physicochemical characteristics of biochar obtained by the thermochemical decomposition of six types of agricultural waste biomass: residues from the production of flavored spirits (a pulp of lime, grapefruit and lemon), beetroot pulp, apple pomace, brewer's spent grain, bark and municipal solid waste (bark, sawdust, off-cuts and wood chips). The biomass conversion process was studied under conditions of limited oxygen access in a reactor. The temperature was raised from 450 to 850 °C over 30 min, followed by a residence time of 60 min. The solid products were characterized in terms of their elemental compositions, mass, energy yield and ash content. The gaseous products from pyrolysis of the biomass were also analyzed and their compositions were characterized by GCMS (Gas Chromatography-Mass Spectrometry). The carbonization process increased the carbon content by, on average, 1.7 times, from an average percentage of 46.09% ± 3.65% for biomass to an average percentage of 74.72% ± 5.36% for biochars. After carbonization, the biochars were found to have a net calorific value of between 27 and 32 MJ/kg, which is comparable or even higher than good-quality coal (eco pea coal 24-26 MJ/kg). The net calorific values show that the volatile products can also be considered as a valuable source of energy.

3.
Nutrients ; 11(2)2019 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-30691123

RESUMEN

Iron deficiency is the most common form of malnutrition. Factors responsible for this so-called "hidden hunger" include poor diet, increased micronutrient needs and health problems such as diseases and infections. Body iron status can be increased by the intake of dietary supplements and fortified food. The aim of the present study was to compare iron bioaccessibility from commercial nutritional supplements and iron microcapsules. A comparison study was performed under conditions mimicking gastric and gastrointestinal digestion. A preparation of encapsulated ferrous sulphate or lactate and vitamin C, in a formula, showed bioaccessibility factors of up to 100% when digested individually, and around 60% in the presence of a food matrix. The degree of oxidation of the ferrous ions differed, depending on the type of preparation, the presence of vitamin C and the food matrix. The highest percentage content of ferrous ion, in the soluble fractions after gastrointestinal digestion, was shown by the preparation containing microencapsulated ferrous lactate or ferrous sulphate and vitamin C. Encapsulation seems to limit the interaction of iron with the food matrix and protect it against oxidation, thus making it more accessible for intestinal uptake.


Asunto(s)
Suplementos Dietéticos/análisis , Alimentos Fortificados/análisis , Hierro/análisis , Hierro/farmacocinética , Adulto , Ácido Ascórbico/análisis , Ácido Ascórbico/farmacocinética , Disponibilidad Biológica , Digestión/fisiología , Composición de Medicamentos , Compuestos Ferrosos/análisis , Compuestos Ferrosos/farmacocinética , Análisis de los Alimentos , Humanos , Modelos Biológicos
4.
Nutrients ; 9(3)2017 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-28335378

RESUMEN

The aim of this study was to investigate the influence of oral iron supplementation, in the form of fortified breads, on the growth performance, health, iron status parameters, and fecal metabolome of anemic piglets. A study was conducted on 24 hybrid (Large White × Landrace × Duroc) piglets. From day 44, the post-natal 12 piglets were supplemented with 100 g of one of two experimental breads, each fortified with 21 mg of ferrous sulphate, either encapsulated or not. After one week of oral supplementation, hematological parameters (hematocrit value, hemoglobin, and red blood cells) showed statistically significant differences (p ≤ 0.05). Piglets fed with the fortified breads had higher iron concentrations in the heart, liver, and intestinal mucosa compared to anemic piglets fed with control bread. Gene expression of hepcidin, iron exporter ferroportin (IREG1), and divalent metal transporter 1 (DMT1), together with concentrations of plasma ferritin, showed no significant statistical differences between groups. Both fortified breads could be used as sources of bioavailable iron. The seven-day intervention trial showed microencapsulation to have only a mild effect on the effectiveness of iron supplementation in the form of fortified bread.


Asunto(s)
Pan/análisis , Alimentos Fortificados , Hierro de la Dieta/farmacocinética , Animales , Disponibilidad Biológica , Proteínas de Transporte de Catión/genética , Proteínas de Transporte de Catión/metabolismo , Modelos Animales de Enfermedad , Composición de Medicamentos , Eritrocitos/metabolismo , Heces/química , Ferritinas/sangre , Hematócrito , Hemoglobinas , Hepcidinas/genética , Hepcidinas/metabolismo , Hierro de la Dieta/administración & dosificación , Hierro de la Dieta/sangre , Metabolómica , Porcinos
5.
J Trace Elem Med Biol ; 29: 91-8, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25468190

RESUMEN

In this study, we investigate the type and quantity of selenium compounds in fish and marine organisms, using ion-pair reversed phase LC­ICP-MS, developed and applied for the analysis of Atlantic cod, Atlantic salmon, Greenland halibut, Atlantic herring, blue mussel, common crab, scallop, calanus, and Euphasia super. Of the samples examined, the lowest level of selenium was found in farmed Atlantic salmon (0.17 mg Se kg(−1) dm). The total selenium extraction efficiency by phosphate buffer was 2.5 times higher in sea plankton and shellfish samples than in fish samples. Analysis of Se species in each hydrolysate obtained by proteolysis showed the presence of selenomethionine, which constituted 41.5% of the selenium compounds detected in hydrolysates of Atlantic herring and 98.4% of those in extracts of Atlantic salmon. Inorganic compounds, such as selenates and selenites, were detected mainly in sea plankton and shellfish samples (<0.13 mg Se kg(−1) wm), although no correlation was found between the presence of inorganic compounds and total selenium concentration. The accuracy of the total selenium determination was validated using a certified reference material (oyster tissue (NIST 1566b)). A lyophilised powder of cod (Gadus morhua) was used to validate speciation analysis, enzymatic hydrolysis of lyophilised powder of cod recovered 54 ± 6% of total selenium, and SeMet constituted 83.5 ± 5.28% of selenium detected in hydrolysates. The chromatographic detection limits were, respectively, 0.30 ng mL(−1), 0.43 ng mL(−1), 0.54 ng mL(−1), 0.55 ng mL(−1), 0.57 ng mL(−1) and 0.72 ng mL(−1) for selenate, selenomethionine, selenite, Se-methyl-selenocysteine, selenocystine and selenomethionine selenoxide.The data on selenium concentrations and speciation presented here could be useful in estimating levels of selenium intake by seafood consumption.


Asunto(s)
Organismos Acuáticos/metabolismo , Cromatografía Líquida de Alta Presión/métodos , Compuestos de Selenio/análisis , Selenio/análisis , Espectrofotometría Atómica/métodos , Animales , Bivalvos/metabolismo , Peces/metabolismo , Plancton/metabolismo , Estándares de Referencia , Reproducibilidad de los Resultados
6.
Nucl Med Rev Cent East Eur ; 14(1): 16-20, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21751167

RESUMEN

BACKGROUND: Positron emission tomography (PET) combined with computer tomography (CT) using (68)Ga-DOTATATE is a promising method for the evaluation of patients with recognised or suspected neuroendocrine tumours (NET). The aim of this study was to assess the diagnostic value of (68)Ga-DOTATATE PET/CT in the visualisation of the expression of somatostatin receptors (SSTR) and identification of new lesions. MATERIAL AND METHODS: Between December 2009 and January 2011 ninety-seven patients with confirmed (88 cases) or suspected (9 cases) NET underwent (68)Ga DOTATATE PET/CT. The primary, confirmed or suspected, NET localizations were: GEP tumours--71 patients; medullary thyroid carcinoma--4 patients; cancer of an unknown primary--14 patients; and NET in other localisations--8 patients. PET/CT acquisitions were performed using standard techniques, 45 to 60 minutes after the intravenous injection of 111-185 MBq (68)Ga-DOTATATE. RESULTS: (68)Ga-DOTATATE PET/CT detected the presence of lesions demonstrating the somatostatin receptor affinity in 50 of the 97 patients (51.5%) and was negative in 47 patients (48.5%). Among 14 patients with metastatic unknown primary cancer, in 5 patients (45.5%) the primary tumour site was identified, and in 4 patients with medullary thyroid cancer distant metastases with SSTR expression were localized in only one patient. CONCLUSIONS: Our findings confirm the diagnostic role of (68)Ga-DOTATATE PET/CT as an accurate method of identifying primary tumours and distant metastases. It provides information on tumour cell receptors status, which has a significant bearing on planning target radionuclide therapy. Overall, (68)Ga-DOTATATE PET/CT can be used in staging, re-staging, and in regular follow up of oncology patients.


Asunto(s)
Tumores Neuroendocrinos/diagnóstico por imagen , Compuestos Organometálicos , Tomografía de Emisión de Positrones , Tomografía Computarizada por Rayos X , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Tumores Neuroendocrinos/metabolismo , Receptores de Somatostatina/metabolismo , Estudios Retrospectivos , Adulto Joven
7.
Plant Foods Hum Nutr ; 62(3): 121-6, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17721822

RESUMEN

The potential of selenium-enriched rye/wheat sourdough bread as a route for supplementing dietary selenium intakes is reported. In addition to their normal diets, 24 female volunteers (24 to 25 years old) were fed either selenium-enriched bread or non-enriched bread each day (68.02 and 0.84 microg selenium day(-1) respectively) for 4 weeks. The chemical form of the selenium in the bread had been characterised using HPLC-ICP-MS, which showed that 42% of the extractable selenium was present as selenomethionine. Plasma selenium levels and plasma platelet glutathione peroxidase (GPx1) activity were measured in the volunteers' blood over a 6-week period. A statistically significant difference (p = 0.001) was observed in the mean percentage change data, calculated from the plasma selenium level measurements for the enriched and control group, over the duration of the study. A comparable difference was not observed for the platelet GPx1 activity (p = 0.756), over the same period. Two weeks after cessation of the feeding stage, i.e., at t = 6 weeks, the mean percentage change value for the selenium plasma levels in the enriched group was still significantly elevated, suggesting that the absorbed selenium had been incorporated into the body's selenium reserves, and was then being slowly released back into the volunteers' blood.


Asunto(s)
Antioxidantes/administración & dosificación , Pan/análisis , Alimentos Fortificados , Selenio/administración & dosificación , Selenio/sangre , Adulto , Antioxidantes/metabolismo , Plaquetas/enzimología , Femenino , Glutatión Peroxidasa/metabolismo , Humanos , Estado Nutricional , Secale , Triticum
8.
Anal Bioanal Chem ; 382(5): 1279-87, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15977033

RESUMEN

In the present study, selenium-enriched plant biomass was investigated to evaluate the ability of rye seedlings to take up, and assimilate, inorganic selenium. Two different analytical approaches were used. Electrophoretic separation (SDS-PAGE) of proteins extracted from 75Se-labelled biomass was used to investigate the biotransformation of selenite into organic forms of the element. Ion-pair chromatography coupled with ICP-MS detection was chosen for the analysis of selenium species, enzymatically extracted from the plant biomass. The results of three enzymatic hydrolysis procedures and three sequential enzymatic extractions procedures are compared. The most effective single extraction was proteolysis (using protease type XIV), giving an overall extraction efficiency of 48%. However, for combinations of enzymes, the most effective was cellulase (Trichoderma viride) followed by sequential extraction of the solid pellet using protease type XIV, giving an extraction efficiency of 70%. The complementary data from the electrophoretic fractionation of proteins, and the HPLC separation of Se-species in the proteolytic digests, reveal the existence of large number of selenium-containing compounds in the rye seedling plant biomass. The results showed the complete biotransformation of inorganic selenium into organic forms during germination of the rye seedlings. HPLC-ICP-MS analysis of extracts from the plant biomass did not show the presence of selenate or selenite. At the time of this study, the lack of suitable organic-MS facilities meant that it was not possible to characterise them fully. However, the data does show that a combination of different enzymes, rather than just the commonly-used protease, should be considered when developing an extraction strategy for selenium in different food types to those already reported in the literature.


Asunto(s)
Análisis de los Alimentos/métodos , Secale/química , Selenio/análisis , Selenoproteínas/aislamiento & purificación , Biomasa , Biotransformación , Celulasa/química , Cromatografía Líquida de Alta Presión , Electroforesis en Gel de Poliacrilamida , Análisis de los Alimentos/instrumentación , Análisis de los Alimentos/normas , Pronasa/química , Control de Calidad , Conteo por Cintilación , Secale/metabolismo , Plantones/química , Plantones/metabolismo , Selenio/farmacocinética , Radioisótopos de Selenio , Espectrometría de Masa por Ionización de Electrospray
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