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Development and implementation of nutrion strategies to improve the application of a food-based dietary guideline for use by créche caregivers in Thulamela Limpopo Province, South AfricaKwinda, Pfanani Charlotte 27 June 2011 (has links)
Many of the world’s children, particularly those living in developing countries, subsist on diets that seldom vary and often do not allow for an adequate intake of the complete range of nutrients required for healthy living. Of concern is the absence of regular consumption of fresh vegetables and fruit that provide vitamin A which, if deficient, impairs children’s growth and development. In South Africa about 21% of children under the age of six years attend crèche facilities on a daily basis. The nutritional state of meals provided to children at many crèches tends to lack micronutrients, particularly vitamin A. Vitamin A deficiency is the main nutritional problem facing crèche children in South Africa today. Underlying causes are unsatisfactory diets restricted in variety and minimal knowledge of optimal dietary practices, a situation exacerbated by a high incidence of food insecurity. Limpopo is a province seriously affected by vitamin A deficiency. A South African study, based on a quantitative research paradigm, was undertaken (April-September 2007) in Thulamela municipality with the aim of developing and implementing nutrition strategies to improve crèche children’s consumption of vitamin A-rich vegetables and fruit, as advocated by an officially recognised food-based dietary guideline. Through convenience sampling, 100 caregivers from 20 crèches in the study area responded to questionnaires and participated in a game. Ongoing observation continued. Information about the participants, their nutrition knowledge and the meals provided was collected following the triple-A cycle approach (assessment, analysis and action). The research process was structured in three phases. Phase one involved a situational assessment and analysis that provided baseline information. Limitations contributing to the problem under investigation were identified and data showed that the children’s intake of vitamin A from vegetables and fruit at crèches was low. This was found to be due to a lack of knowledge and information about vitamin A, coupled with the unavailability and inaccessibility of food primarily due to non-production and affordability. Food preparation, storage and preservation also posed challenges to caregivers. Using evidence from documented studies and the findings from phase one, nutrition strategies were developed and implemented in phase two. Caregivers were shown how to increase the availability and use of foods rich in vitamin A and were encouraged to grow, and use, both cultivated and non-cultivated vitamin A-rich vegetables and fruit. Furthermore, the concept of the food-based dietary guideline “eat plenty of vegetables and fruits everyday” was introduced to the caregivers and became part of the developed nutrition strategies. Follow-up data collected in phase three showed substantial advancement in caregivers’ knowledge and skills. Access, availability and utilisation of vitamin A-rich vegetables and fruit had improved markedly. Flourishing vegetable gardens, planned menus and well prepared meals were concrete evidence, and vegetables and fruit were more frequently served to children. Implementation of the developed nutrition strategies epitomised the envisaged outcome of this study. Based on the research results, important recommendations are made to enhance the appropriate consumption of vegetables and fruit rich in vitamin A, leading to a reduction in disease and death caused by vitamin A deficiency among children. / Dissertation (MConsumer Science)--University of Pretoria, 2010. / Consumer Science / unrestricted
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Environmentální faktory ovlivňující tělesnou vůni člověka / The Environmental Effects on Human Body OdourDneboská, Tereza January 2012 (has links)
The main source of the human body odour is an axillary region. Human body odour is individually specific and results from genetic and environmental factors. Human body odour is an important sexual attractant for potential partners. It is influenced by environmental factors, such as an emotional state and health. Important environmental factors influencing human body odour are also eating habits. However, we know very little about how particular dietary components shape our body odour. Only the effect of red meat and garlic consumption have been tested. Here we tested the effect of caffeine (from usual source and guarana) and beta- carotene. In our three experiments we used a balanced within-subject experimental design. Volunteers donated twice their body odour: once after ingestion of the tested substance, second time in the control situation. Samples were then assessed for their attractiveness and intensity by group of women. Results showed that caffeine consumption may influence negatively attractiveness and intensity of human body odour. Guarana and beta-carotene did not show any significant results. These results partially confirmed that dietary factors influence the quality of the human body odour. This field should be further studied as a part of the environmental factors influencing human...
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Dyeing and Printing Natural Fibers with Algae-Based ColorantsMoldovan, Simona 17 January 2022 (has links)
[ES] La inminente necesidad de un desarrollo sostenible ha influido en el crecimiento de la industria, abriendo el camino para la transición progresiva hacia una bioeconomía sostenible. La evolución de la industria textil, caracterizada por altos niveles de contaminación, exige la continua exploración de alternativas a los recursos fósiles y procesos contaminantes. En este sentido, el presente estudio propone la exploración de una alternativa sostenible de colorantes naturales procedentes de biomasa de algas, para su aplicación en procesos de coloración, seleccionados por su reducido impacto ambiental, tanto en el cultivo de las algas, como en la extracción de colorantes, y su posible aplicación textil. Este estudio tiene como objetivo explorar la viabilidad del uso de colorantes procedentes de algas para su aplicación en procesos de coloración textil, como la tintura por agotamiento y estampación pigmentaria. La selección de micro y macroalgas ha sido realizada según criterios que facilitan un cultivo optimizado y simple, ofreciendo diferentes colores básicos para la industria textil, como son el azul (C-ficocianina), el rojo (R-ficoeritrina), el amarillo (ß-caroteno), y el verde (Clorofila a). Los extractos líquidos concentrados en colorantes se han empleado en los procesos seleccionados de acabado textil, para conferir color a fibras naturales, como el algodón y la lana. La viabilidad de las fuentes alternativas de colorantes sostenibles mencionadas anteriormente ha sido estudiada mediante el análisis de la influencia de ciertos auxiliares de coloración, como son los mordientes. Una serie de mordientes convencionales (metálicos, y recién descubiertos) y biomordientes han sido seleccionados para investigar su capacidad de mejora de las propiedades y eficacia de coloración de los colorantes sostenibles. Asimismo, se han estudiado aproximaciones teóricas relacionados con la posible unión fibras-mordientes-colorantes. La implicación del uso de mordientes en los procesos de tintura por agotamiento y estampación pigmentaria se ha caracterizado a través de la medición de las coordenadas cromáticas del espacio de color; el espectro de reflectancia junto con la fuerza del color. El análisis se ha completado con el cálculo del coeficiente de absorción, en base al colorante remanente en los efluentes del agua residual de tintura (para los procesos de tintura). No obstante, la influencia de los mordientes sobre la calidad de los procesos de coloración ha sido evaluada mediante ensayos de medición de solideces al lavado y a la luz realizados según normativas europeas en vigor. El proceso de tintura por agotamiento se ha optimizado para determinar los valores óptimos para la temperatura, relación de baño de tintura, pH, tiempo de proceso, teniendo en cuenta la sensibilidad de los colorantes frente a los factores degradantes y de proceso. Siguiendo el carácter sostenible del proceso, se ha realizado una evaluación preliminar de los efluentes de aguas residuales de tinturas, a través de mediciones de indicadores como DBO5, DQO, contenido en metales, y el comportamiento frente a un tratamiento biológico de aguas residuales. Igualmente, se investigó el posible valor añadido de los colorantes estudiados, midiendo la capacidad de protección solar y antimicrobiana. El proceso de estampación pigmentaria abordó la investigación de la viabilidad de los colorantes mediante el empleo de la pasta de estampación sintética convencional, completada con la evaluación de la alternativa representada por la pasta de estampación natural, considerando, al mismo tiempo, la disponibilidad comercial de los componentes. Los resultados obtenidos confieren una validación preliminar de la idoneidad de la aplicación de materia colorante procedente de algas en procesos de tintura por agotamiento y la estampación pigmentaria sobre sustratos textiles de algodón y lana, a escala de laboratorio, con elementos clave para las perspectivas de funcionalización textil, abriendo así el camino para
futuras investigaciones que hará posible el escalado de los procesos y el uso industrial de
materiales alternativos sostenibles en la industria textil. / [CA] La creixent necessitat per a un desenvolupament sostenible ha tingut un gran impacte en el creixement de la indústria, obrint el camí per a la transició progressiva cap a una bioeconomia sostenible. L'evolució de la indústria tèxtil, caracteritzada per els alts nivells de contaminació fomenta la contínua exploració d'alternatives als recursos fòssils i processos contaminants. En aquest sentit, el present estudi proposa l'exploració d'una alternativa sostenible de colorants naturals procedents de biomassa d'algues, per a la seua aplicació en processos de coloració, seleccionats a causa de l'impacte ambiental reduït, generat pel cultiu de les algues, l'extracció de colorants, i la seua possible aplicació tèxtil. Aquest estudi té com a objectiu explorar la viabilitat de l'ús de colorants procedents d'algues per a la seua aplicació en processos de coloració tèxtil, com la tintura per esgotament i estampació pigmentària. La selecció de micro i macroalgues ha sigut realitzada segons criteris que faciliten un cultiu optimitzat i senzill, que proveeix colors bàsics per a la indústria tèxtil, com són el blau (C- ficocianina), el roig (R-ficoeritrina), el groc (ß-caroteno, i el verd (Clorofil·la a) . Els extractes líquids concentrats en colorants s'han emprat en els processos seleccionats d'acabat tèxtil, per a conferir color a fibres naturals, com el cotó i la llana. La viabilitat de les fonts alternatives de colorants sostenibles mencionades anteriorment ha sigut abordada per mitjà de l'anàlisi de la influència de certs auxiliars de coloració, com són els mordents. Una sèrie de mordents convencionals, metàl·lics, acabats de descobrir i bio mordents ha sigut seleccionada per a investigar la seua capacitat de millora de les propietats i eficàcia de coloració dels colorants sostenibles. A més a més, es va estudiar aproximacions teòriques relacionades amb la unió plausible entre fibres-mordents-colorants. La implicació de l'ús de mordents en els processos de tintura per esgotament i estampació pigmentària s'ha analitzat mitjançantassajos de caracterització, contemplant la caracterització objectiva del color per mitjà del mesurament de les coordenades cromàtiques de l'espai de color; l'espectre de reflectància junt amb la força del color; anàlisi completada pel càlcul del coeficient d'absorció, a base del colorant romanent en els efluents de l'aigua residual de tintura (per als processos de tintura). No obstant això, la influència dels mordents sobre la qualitat dels processos de coloració ha sigut avaluada per mitjà d'assajos de mesurament de solideses al llavat i a la llum realitzats segons normatives europees en vigor. El procés de tintura per esgotament ha sigut optimitzat per a determinar els valors òptims per a la temperatura, relació de bany de tintura, pH, temps de procés, valorant el caràcter sensible dels colorants front als agents degradants i de procés. Recolzant el caràcter sostenible del procés, s'ha realitzat una evaluación preliminar dels afluents d'aigües residuals de tintures, mitjançant mesuraments d'indicadors, com DBO5, DQO, contingut en metalls, i el comportament enfront d'un tractament biològic d'aigües residuals. Igualment, es va investigar el possible valor afegit dels colorants procedents d'algues, mesurant la capacitat de protecció solar i antimicrobiana. El procés d'estampació pigmentària va abordar la investigació de la viabilitat dels colorants per mitjà de l'ocupació de la pasta d'estampació sintètica convencional, completada amb l'avaluació de l'alternativa representada per la pasta d'estampació natural, considerant, al mateix temps, la disponibilitat comercial dels ingredients. Els resultats obtinguts confereixen una validació preliminar de la idoneïtat de l'aplicació de matèria colorant procedent d'algues en processos de tintura per esgotament i l'estampació pigmentària sobre substrats tèxtils de cotó i llana, a escala de laboratori, amb elements clau per a les perspectives de funcionalització tèxtil, obrint així el camí per a futures investigacions que farà possible l'escalat dels processos i l'ús industrial de materials alternatius sostenibles a la indústria tèxtil. / [EN] The crucial need for sustainable development has an immense impact on industrial evolution paving the path for a progressive transition towards a sustainable bioeconomy. Considering the pollutant evolution of the textile industry, approaches to exploring environmentally friendly alternatives to fossil-based resources and polluting processes have become the most current practice nowadays. In this sense, this study proposes the exploration of a sustainable alternative colorant material for coloration applications, from algae-based feedstock, considering the reduced environmental pressure embroiled by algae cultivation, colorant extraction, and its possible further textile application.
This study explores the viability of the use of algae-based colorants for their application in exhaustion dyeing and pigment printing coloration techniques for the textile industry. Micro and macroalgae strains selection was performed according to criteria ensuring facile and optimized cultivation and the provision of basic colors for the textile industry as blue (C-phycocyanin), red (R-phycoerythrin), yellow (ß-carotene), and green (Chlorophyll-a). Liquid colorant-rich extracts were employed in the selected textile finishing processes on natural fibers, like cotton and wool.
To approach the viability of these alternative sustainable colorants and enhance coloration properties and efficiencies, a series of auxiliaries were assessed, as conventional metallic and newly discovered mordants, and biomordants. Theoretical assumptions related to the plausible bonding among fibers-mordants-colorants were approximated. The auxiliaries implication in exhaustion dyeing and pigment printing processes were analyzed through a series of characterization tests, envisaging objective color characterization determined by the measurement of CIELab color coordinates; reflectance spectrum, and color strength approaching the depth of the coloration; completed by the calculation of the absorption coefficient, based on the remaining colorant matter in the wastewater effluents (for the dyeing process). Nevertheless, the mordants' influence on the quality of the coloration process was assessed through laundering and lightfastness measured according to European standards for textiles characterization.
The dyeing exhaustion process was also subjected to parameters optimization in terms of the definition of optimum temperature, dyeing liquor ratio, pH, and time, considering the colorants' sensibilities for degrading and processing agents.
A preliminary nearing towards the dyeing wastewater effluent quality assessment supporting the sustainability character of the process was performed through the measurement of basic water characterization indicators as BOD5, COD, metal content, and behavior against biological wastewater treatment. Furthermore, the possible added value of the algae-based colorants was investigated by measuring the antimicrobial and solar protection capacity, enlarging the application prospects of these innovative raw materials for textile applications.
The pigment printing process approached the research of the feasibility of the colorants by employing the conventional synthetic printing paste, completed with the assessment of alternative natural printing paste, considering, at the same time the commercial availability of ingredients.
The obtained results confer a preliminary validation of the suitability of the application of algae-based colorant matter in exhaustion dyeing and pigment printing of cotton and wool, at laboratory scale, with key elements for textile functionalization perspectives, thus paving the path for further investigation which will make possible the upscaling of the processes and industrial use of alternative sustainable materials in the textile industry. / Moldovan, S. (2021). Dyeing and printing Natural Fibers with Algae-Based Colorants [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/180349 / TESIS
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Effects of sweet potato forage meals on protein and energy supply, beta-carotene and blood glucose content of dairy cattle milkSmit, Christiaan Jacobus 12 May 2015 (has links)
Forage of beta-carotene-fortified orange-fleshed sweet potato is essential for alleviation cattle malnutrition. The study aims were to determine effects of supplementing sweet potato (SP) roots and sun dried forage on degradation of dietary legumes, intake and milk yield in dairy cattle. Mature SP roots were oven dried and forage vines and leaves (V&L) sun dried. Lactating dairy were supplied meals with total mixed ration (TMR) constituting varying levels of sweet potato forage and concentrate. The SP flour was rapidly and completely degraded In Sacco while degradability of V&L was comparable to that of Lucerne hay. Rumen degradation of Lucerne was reduced when the legume was incubated proximal to SP. Substitution of TMR with fresh SP forage and flour meal increased degradability of diets. Glucose post-feeding was increased (P<0.05) by SP roots but no change in milk yield. Orange-fleshed SP forage is recommended for improving energy supply in lactating cow diets / Agriculture and Animal Health / M. Sc. (Agriculture)
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Antioxidants as Risk Factors for Gingival BleedingBahng, Hee-Jeong 01 January 2004 (has links)
Background: Studies of gingival bleeding and the effects of antioxidants on extracellular matrix and immunologic and inflammatory responses provide a rationale for hypothesizing that antioxidants reduce the risk for gingival bleeding.Methods: This study evaluated the role of antioxidants as contributing risk factors for gingival bleeding utilizing the Third National Health and Nutrition Examination Survey (NAHNES III). A sample of 18,825 adults (20 to ≥ 90 years of age), with dental measurement and assessment of serum levels of antioxidants were included in the study. Gingival bleeding was defined as those who had more than 30 percent of gingival bleeding in 28 sites examined. SPSS version 11.0 software and Epi-info 2000 were used to perform the statistical analysis.Results: Using multiple logistic regression in five separate antioxidants, the study showed an association between increased plasma levels of vitamin C (ascorbic acid) and decreased risk for gingival bleeding (OR= 0.33; 95% CI 0.15 to 0.72). An inverse relationship was also found between gingival bleeding and serum levels of beta carotene (OR=1.93; 95% CI 1.05 to 3.54). However, negative association was found between gingival bleeding and vitamin A (OR=2.60; 95% CI 1.04 to 6.50). No statistically significant association was observed between gingival bleeding and serum levels in vitamin E (alpha tocopherol) and selenium.Conclusion: Antioxidants, vitamin C, vitamin A, and beta carotene, were significant risk factors for gingival bleeding. This should be emphasized for improving the oral health of the U.S. adult population.
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Estabelecimento da vida útil de hortaliças minimamente processadas sob atmosfera modificada e refrigeração. / Establishing the shelf life of minimally processed vegetables by modified atmosphere and refrigeration.Pilon, Lucimeire 28 August 2003 (has links)
As perdas pós-colheita de alimentos hortícolas justificam a adoção de técnicas de conservação. Uma vez beneficiados, esses produtos permitem agregar valor à produção primária e se tornam de conveniência ao consumidor. Essa pesquisa teve como objetivo definir as metodologias do processamento mínimo de cenoura, pimentão e salada mista (batata e vagem), quanto ao tipo e intensidade de adoção das técnicas de barreiras e monitorar o processamento, via controle microbiológico, sensorial, físico-químico e nutricional. As hortaliças foram lavadas em água corrente, descascadas e cortadas com facas afiadas de aço inoxidável. Para a sanificação, foram imersas por 15 min em água refrigerada (± 7ºC) com 100 mg L-1 de cloro livre a pH ajustado para 7,0; a seguir foram centrifugadas a 550-900 G, por 5 min. As hortaliças foram acondicionadas, manualmente, em sacos plásticos de filme multicamada laminado, do tipo BOPP/PEBD (polipropileno biorientado/polietileno de baixa densidade). As embalagens foram fechadas em seladora modelo AP-500, marca Tec Maq, sob ar atmosférico, vácuo e atmosfera modificada (2% de O2, 10% CO2 e 88% de N2) e a seguir foram armazenados sob refrigeração a 1ºC ± 1ºC. A vitamina C não foi afetada em nenhum dos tratamentos nos três produtos. Os teores de b-caroteno mantiveram-se praticamente constantes em cenoura e salada mista; no pimentão, após a primeira semana de armazenamento, sofreram um decréscimo, permanecendo praticamente inalterados ao longo do armazenamento. Quanto à análise sensorial, os resultados para a cenoura e salada mista, foram satisfatórios até 21 dias de armazenamento para todos os tratamentos; exceto para o pimentão. Os três produtos obtiveram em todos os tratamentos, contagens para psicrotróficos variando de 10 2 a 10 5 UFC/g, 10 1 a 10 3 UFC/g e 10 3 a 10 6 UFC/g, respectivamente. Anaeróbios mesófilos e coliformes totais, foram constatados em pimentões minimamente processados. Porém, as baixas contagens obtidas, em todos os tratamentos, mostraram que a vida útil destes prolongou-se até o 14º dia de armazenamento. Para a cenoura e salada mista minimamente processadas, não foram constatados coliformes totais e fecais, anaeróbios mesófilos e Salmonella em nenhum dos tratamentos. / The postharvest losses of horticultural products justify the adoption of preservation techniques. Once these products are processed, they add value to the primary products and they become convenient to the consumer. This research had the purpose of defining the methodologies for minimal processing of carrot, green pepper and mixed salad of potato and string bean in relation to the type and intensity of adoption of the barrier techniques. In addition, it was our objective to monitor the processing, through by microbiological, sensory, physical-chemical and nutritional evaluation. The vegetables were washed in running water, peeled and cut with sharp stainless steel knives. For the sanitization they were submerged, for 15 min, in cold water (± 7ºC) with 100 mg L -1 of free chlorine at pH 7,0; next, they were centrifuged at 550-900 G, for 5 min. The product was hand packed in plastic bags BOPP/LDPE (biorientated polypropylene/low-density polyethylene). The packages were sealed under air, vacuum and modified atmosphere (2% O2, 10% CO2 and 88% N2) and stored under refrigeration at 1ºC±1ºC. The vitamin C content was not affected in any of the treatments. The values for b-carotene remained stable for carrot and mixed salad. For the green pepper, the values decreased after the first week of storage. In relation to the sensory analysis, carrot and mixed salad were considered satisfactory until 21 days of storage for all treatments; but for green pepper. In all treatments, counts for the three products ranged psychrotrophic ranging from 10 2 to 10 5 UFC g -1 , 10 1 to 10 3 UFC g -1 , 10 3 to 10 6 UFC g -1 , respectively. Anaerobic mesophiles and total coliforms were observed in minimally processed green peppers. However, the low count obtained in all treatments indicated a shelf life of 14 days. For the minimally processed carrot and mixed salad, no total or fecal coliforms, anaerobic mesophiles and Salmonella were observed in any of the treatments.
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Comparação entre a biodisponibilidade do β-caroteno sintético e de fonte natural (couve-manteiga): papel de fibra alimentar em animais de laboratório / Comparison between the bioavailability of synthetic and natural source β-carotene (kale-butter): dietary fiber paper in laboratory animalsZanuto, Marcia Elena 24 November 2000 (has links)
Este trabalho, buscou comparar a biodisponibilidade do β-caroteno sintético e de fonte natural (couve-manteiga), e verificar os efeitos da fibra alimentar (pectina cítrica) sobre a biodisponibilidade do β-caroteno, dentro de 2 experimentos diferentes (ratos e coelhos). No Experimento I (ratos), um grupo de animais recebeu ração com β-caroteno e isenta de pectina cítrica (GC) e outro recebeu ração com β-caroteno e adição de pectina cítrica (GE). No Experimento II (coelhos), um grupo de animais recebeu ração com β-caroteno sintético (GCP), outro recebeu β-caroteno de fonte natural (couve-manteiga) (GV) e ainda outro não recebeu de β-caroteno (GCN); todos os grupos de coelhos receberam pectina cítrica. Após 30 dias de experimento, os animais foram sacrificados para determinações plasmáticas e hepáticas de vitamina A e β-caroteno, por HPLC. Dos resultados obtidos no estudo em ratos pode-se verificar que o grupo de animais que recebeu pectina (GE), apresentou menor (p<0,05) concentração hepática total de vitamina A (µg/peso de fígado) (retinol: GC =47,61 ± 24,24 e GE =23,44 ± 9,68 e palmitato de retinila: GC =935,30 ± 428,19 e GE =282,34 ± 98,86) e β-caroteno (µg/peso de fígado) (GC =9,64 ± 3,07 e GE =1,01 ± 0,66) que o grupo que não recebeu pectina (GC). E dos resultados obtidos no experimento em coelhos, verificou-se que o grupo que recebeu β-caroteno de fonte natural (GV), obteve concentração hepática total de vitamina A (mg/peso de fígado) (retinol: GV = 2,30 ± 0,67, GCP =2,07 ± 0,57 e GCN = 0,11 ± 0,08; palmitato de retinila: GV =4,42 ± 2,17, GCP =2,77 ± 0,73 e GCN =0,04 ± 0,02) e β-caroteno (mg/peso de fígado) (GV =0,04 ± 0,01, GCP =0,03 ± 0,01 e GCN =não detectado), maior (p<0,05) que o grupo que recebeu β-caroteno sintético (GCP). Conclui-se que no Experimento I (ratos), a pectina cítrica provavelmente interferiu na absorção do p-caroteno, e no Experimento II (coelhos), que o β-caroteno de fonte natural (GV), foi melhor absorvido comparando-se com o β-caroteno sintético, na presença de pectina cítrica. / This work, looked for to compare the bioavailability of synthetic p-carotene and of natural source (kale), and to verify the effects of the alimentary fiber (citrus pectin) on the bioavailability of β-carotene, inside of 2 different experiments (rats and rabbits). In the Experiment I (rats), a group of animals received diet with β-carotene and it exempts of citrus pectin (CG) and another received diet with β-carotene and addition of citrus pectin (EG). In the Experiment II (rabbits), a group of animals received diet with synthetic β-carotene (PCG), another received β-carotene of natural source (kale) (VG) and still another didn\'t receive from β-carotene (NCG); all the groups of rabbits received citrus pectin. After 30 days of experiment, the animals were sacrificed for determinations plasmatics and vitamin liverworts A and β-carotene, by HPLC. Of the results obtained in the study in rats it can be verified that the group of animals that received pectin (EG), it presented smaller (p <0,05) concentration hepatic vitamin total A (liver mg/weight) (retinol: CG = 47.61 ± 24.24 and EG = 23.44 ± 9.68 and retinyl palmitate: CG = 935.30 ± 428.19 and EG = 282.34 ± 98.86) and β-carotene (liver mg/weight) (CG = 9.64 ± 3.07 and EG = 1.01 ± 0.66) that the group that didn\'t receive pectin (CG). And of the results obtained in the experiment in rabbits, it was verified that the group that received β-carotene of natural source (VG), obtained concentration hepatic vitamin total A (liver mg/weight) (retinol: VG = 2.30 ± 0.67, PCG = 2.07 ± 0.57 and NCG = 0.11 ± 0.08; retinyl palmitate: VG = 4.42 ± 2.17, PCG = 2.77± 0.73 and NCG = 0.04 ± 0.02) and β-carotene (liver mg/weight) (VG = 0.04 ± 0.01, PCG = 0.03 ± 0.01 and NCG = not detected), larger (p <0,05) that the group that received synthetic β-carotene (PCG). Ended that in the Experiment I (rats), the citrus pectin probably interfered in the absorption of the p-carotene, and in the Experiment II (rabbits), the β-carotene of natural source (VG), it was absorbed being compared with the synthetic β-carotene better, in the presence of citrus pectin.
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Produção e caracterização de celulose cristalina e amorfa e de partículas de quitosana para aplicação como estabilizantes de emulsões óleo-em-água / Production and characterization of crystalline and amorphous cellulose and chitosan particles for application as stabilizers of oil-in-water emulsionsBertan, David Willian 24 July 2018 (has links)
Emulsões são sistemas formados quando dois componentes imiscíveis são misturados, na forma de gotículas dispersas numa fase contínua, estabilizados pela ação de emulsificantes, compostos anfifílicos, com afinidades por ambas as fases do sistema. No caso de emulsões de Pickering, o sistema é estabilizado por partículas coloidais sólidas, que adsorvem à interface das gotículas da emulsão. O objetivo desta dissertação foi produzir e caracterizar suspensões de celulose cristalina (CC), celulose amorfa (CA) e de partículas de quitosana (PQ) e avaliar seu potencial de aplicação como únicos compostos estabilizantes em emulsões óleo-em-água. As CC e CA foram produzidas por tratamentos térmico e ácido de celulose microcristalina, respectivamente, enquanto que as PQs foram produzidas por tratamento ácido de quitosana de média massa molecular. Em todos esses casos, os tratamentos foram seguidos de ultra-agitação: 0 (ST), 10000 (UT10), 15000 (UT15) ou 20000 rpm (UT20) por 3 minutos. As suspensões de CC, CA e PQ foram caracterizadas para determinação da distribuição do tamanho de partículas, do potencial zeta e da estabilidade física, e por microscopia eletrônica de varredura e/ou de força atômica. As partículas em pó, produzidas por liofilização, foram submetidas a análises de difração de raios-X, espectroscopia de infravermelho com Transformada de Fourier (FTIR) e de colorimetria instrumental. Em função dessas caracterizações, foi estudado o efeito do tipo de partícula estabilizadora (CC, CA ou PQ) sobre o tamanho de gotas, colorimetria instrumental e estabilidade física de emulsões com 20% (v/v) de óleo de soja, sem e com β-caroteno. Observou-se que os tratamentos UT10, UT15 e UT20 provocaram importantes alterações na distribuição de tamanho de partículas, com redução do tamanho médio das partículas, sem efeito significativo da velocidade de agitação. Em relação à PQ, os tratamentos por ultra-agitação não influenciaram o tamanho de partículas, nem quando comparado com suspensões ST. A CC apresentou-se em fragmentos de fibras celulósicas e altamente instáveis em suspensão, com índices de instabilidade próximos a 0,78. A CA apresentou-se em partículas coloidais e agregados irregulares, com estabilidade física razoável em suspensão (0,26). As suspensões de PQ apresentaram grandes estruturas cristalinas de acetato de sódio, junto a partículas coloidais de quitosana, mas altamente estáveis em suspensão aquosa (0,04). De forma geral, o potencial ζ e a estabilidade física das suspensões de CC, CA e PQ não variaram com o tratamento (ST, UT10, UT15 e UT20). Na caracterização das partículas liofilizadas, constatou-se alto índice de cristalinidade da CC (81%), e baixa cristalinidade da CA (42%) e da PQ (40%). Os tratamentos não provocaram modificações consideráveis na estrutura química, analisada por FTIR, e nem na cor instrumental da CC, CA e PQ. Por fim, apenas a PQ foi capaz de produzir e estabilizar emulsões óleo-em-água, não havendo formação de fase creme durante o armazenamento. A adição de 0,005% de β-caroteno à fase lipídica deixou as emulsões estabilizadas por PQ ligeiramente alaranjadas e aumentou sua estabilidade física, sem afetar o tamanho médio de suas gotas (29-32 µm). Portanto, apenas a PQ demonstrou potencial para estabilizar emulsões óleo-em-água, com ou sem β-caroteno. / Emulsions are systems formed when two immiscible components are mixed, presenting dispersed droplets in a continuous phase, stabilized by emulsifiers, amphiphilic compounds, with affinities for both phases of the system. In the case of Pickering emulsions, the system is stabilized by solid colloidal particles, which adsorb at the interface of the emulsion droplets. The objective of this dissertation was to produce and characterize suspensions of crystalline cellulose (CC), amorphous cellulose (CA) and chitosan particles (PQ) and to evaluate its potential as single stabilizing compounds in oil-in-water emulsions. CC and CA were produced by heat and acidic treatments of microcrystalline cellulose, respectively, whereas PQs were produced by acidic treatment of medium molecular weight chitosan, also followed by ultra-stirring treatment. In all cases, the treatments were followed by ultra-stirring: 0 (ST); 10,000 (UT10); 15,000 (UT15) or 20,000 rpm (UT20) for 3 minutes. The suspensions of CC, CA and PQ were characterized for determination of particle size distribution, zeta potential and physical stability, and by scanning electron microscopy and/or atomic force microscopy. The powder particles, produced by freeze-drying, were subjected to analysis by X-ray diffraction, Fourier Transform infrared spectroscopy (FTIR) and instrumental colorimetry. As a function of these characterizations, the effect of the stabilizing particle type (CC, CA or PQ) on droplet size, instrumental colorimetry and physical stability of emulsions with 20% (v/v) soybean oil, without and with β-carotene was studied. It was observed that the treatments UT10, UT15 and UT20 caused important changes in the particle size distribution, with reduction of the mean particle size, without significant effect of the agitation speed. Regarding chitosan particles, ultra-stirring treatments did not influence particle size, neither when compared to suspensions without pretreatment. CC was presented as highly unstable cellulosic fiber fragments in suspension, with instability indexes close to 0.78. CA was presented in colloidal particles and irregular aggregates, with reasonable physical stability in suspension (0.26). The suspensions of PQ showed large crystalline structures of sodium acetate, together with colloidal chitosan particles, but highly stable in aqueous suspension (0.04). In general, the potential ζ and the physical stability of CC, CA and PQ suspensions did not change with the treatment (ST, UT10, UT15 and UT20). In the characterization of the freezedried particles, a high crystallinity index of CC (81%) was observed, whereas CA (42%) and PQ (40%) showed low crystallinities. The treatments neither caused significant changes in the chemical structure, analyzed by FTIR, nor in the instrumental color of CC, CA and PQ. Finally, only PQ was able to produce and stabilize oil-in-water emulsions, with no cream phase formation during storage. Addition of 0.005% β-carotene to the oil phase left the emulsions stabilized by PQ slightly orange and increased the physical stability of the emulsions, without affecting the droplet size of the emulsions (29-32 µm). Therefore, only PQ demonstrated the potential to stabilize oil-in-water emulsions, with or without β-carotene.
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Food structure design to modulate bioaccessibility of carotenoids from brazilian native fruits after screening of eleven non-conventional tropical fruits / Desenho estrutural da matriz alimentar para modulação da bioacessibilidade de carotenoides de frutas nativas do Brasil após a triagem de onze frutas tropicas não-convencionaisPaulo Roberto de Araujo Berni 26 October 2018 (has links)
Brazil is the country with the greatest biodiversity on the planet and a major producer of food. Tropical fruits, especially natives from Brazil, may contain considerable amounts of carotenoids that have antioxidant, anti-inflammatory, provitamin A and anticancer actions, such as β-carotene and lycopene. The food structure design concept aims to manipulate the food matrix for specific purposes, e.g. the preservation and manipulation of carotenoid bioaccessibility. The aim of this thesis was to explore tropical fruits, native and exotic from Brazil in the development of delivery systems for carotenoids. A screening step was carried out with 11 fruits, among which 2 were selected, the pitanga (Eugenia uniflora) and buriti (Mauritia flexuosa) fruits that were used for the production of microemulsions. At the screening were evaluated the proximate composition, fiber contents, carotenoid profiles and bioacessibilities. The nutritional value demonstrated that these fruits have high potential as raw-materials for healthy products due to their high fiber, minerals and carotenoid contents in addition to low energy value. Analysis by HPLC-DAD allowed the identification of 14 carotenoids in the 11 fruits studied for the screening. Results demonstrated the superiority of the bioaccessibility of xanthophylls (ranging 10 % - 52 %) in relation to carotenes, and the low bioaccessibility of lycopene from pitanga (1.1 %) and average bioaccessibility of β-carotene from buriti (26 %). Pitanga and buriti had their carotenoid profiles analyzed and monitored throughout an in vitro simulation of the digestion coupled with caco-2 cell cultures. Although xanthophylls are more bioaccessible, the intestinal ephitelium absorb preferentially the provitamin A carotenoids, such β-carotene and β-criptoxanthin. In order to produce these microemulsions, high-speed homogenization (HSH) and ultrasound (US) were studied in combination with the use of surfactants (Whey Protein Isolate and Tween 80), and addition of corn oil as carotenoid carrier. The experiments have shown that the interaction of US and HSH is capable to break cell walls and release carotenoids with higher efficiency. Optical and fluorescence microscopy, as well as carotenoid analysis demonstrated that it was possible to manipulate the food matrix structure releasing the carotenoids from the plant cells and encapsulating them inside the oil droplets, what increased their retention after processing. The microemulsion were affected by time of processing and by surfactant related to their rheology, final structure, stability of emulsion and carotenoid stability to processing. Finally, a dynamic gastrointestinal system was used to compare the behavior of carotenoids from whole fruit pulps and selected microemulsions (2% Tween 80, 5% corn oil, processed by HSH-US 4 min -4 min). The results demonstrated that it was possible to increase the stability to digestion and bioaccessibility of total carotenoids, lycopene and β-carotene from the microemulsions. / O Brasil é o país detentor da maior biodiversidade do planeta e um grande produtor de alimentos. Frutas tropicais, em especial as nativas brasileiras, podem conter quantidades consideráveis de carotenoides que possuem ação antioxidante, anti-inflamatória, provitamina A e anticâncer, como β-caroteno e licopeno. O desenho estrutural dos alimentos (food structure design), visa manipular a matriz alimentar com fins específicos, por exemplo, a preservação e manipulação da bioacessibilidade de carotenoides. Na presente tese buscou-se explorar frutas brasileiras não-convencionais no desenvolvimento de sistemas de entrega de carotenoides. Foi realizada uma etapa de triagem com 11 frutas, dentre as quais, 2 foram selecionadas, a pitanga (Eugenia uniflora) e o buriti (Mauritia flexuosa), e utilizadas na produção de microemulsões. Nesta triagem foram avaliadas a composição centesimal, o teor de fibras, o perfil de carotenoides e a bioacessibilidade destes carotenoides. O valor nutricional das frutas demonstrou seu potencial para utilização em produtos saudáveis, devido a seus teores eleveados de fibras, minerais e carotenoides além do baixo teor calórico. A análise por HPLC-DAD permitiu identificar até 14 carotenoides nas amostras das 11 frutas estudadas na triagem. O estudo da bioacessibilidade dos carotenoides das 11 frutas demonstrou principalmente a superioridade da bioacessibilidade de xantofilas (variando de 10 a 52 %) em relação aos carotenos, e portanto a baixa bioacessibilidade de licopeno da pitanga (1,1%) e média bioacessibilidade de β-caroteno do buriti (26%). Pitanga e buriti tiveram o perfil de carotenoides detalhadamente acompanhados através da simulação in vitro da digestão associada à absorção intestinal por culturas de células Caco-2. Neste estudo, observou-se que embora as xantofillas sejam mais bioacessíveis, o tecido epitelial do intestino absorve preferencialmente carotenoides provitaminicos A, como o β-caroteno e a β-criptoxantina. Para produzir as microemulsões foram estudados processamentos (homogeneização de alta-velocidade - HSH e ultrassom - US) em combinação com uso de surfactantes (Whey Protein Isolate e Tween 80) e adição de óleo de milho como carreador dos carotenoides. Os experimentos mostraram que a interação entre US e HSH é capaz de romper as paredes celulares e liberarem os carotenoides com maior eficiência. Ficou demonstrado através de microscopia ótica e de fluorescência, tanto quanto pela análise de carotenoides, que foi possível manipular estruturalmente a matriz alimentar liberando os carotenoides de dentro das células vegetais e encapsulando-os dentro das gotículas de óleo, além de aumentar sua retenção após o processamento. As microemulsões obtidas sofreram efeito do tempo de processamento e do surfactante em relação à reologia, estrutura final da matriz, estabilidade ao armazenamento e estabilidade dos carotenoides ao processo. Por fim, foi utilizado um sistema dinâmico de simulação da digestão gastrointestinal para comparar o comportamento dos carotenoides oriundos das polpas integrais das frutas e das microemulsões selecionadas (Tween 80 a 2%, óleo de milho a 5% e processado por HSH-US 4 min-4 min). Os resultados demonstraram que foi possível aumentar a estabilidade à digestão e a bioacessibilidade dos carotenoides totais, do licopeno e do β-caroteno.
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Efeitos da associação do beta-caroteno, alfa-tocoferol e do fumo no câncer de pulmão.Saad, Paulo César Bálade 19 June 2006 (has links)
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Previous issue date: 2006-06-19 / Cigarettes accounts for the death of millions of people a year worldwide, directly related to lung cancer. Some studies have shown that larger plasmatic indexes of beta-carotene or a great ingestion of foods rich in carotenoids diminish the risk of developing this neoplasia. On the other hand, studies suggest that the smokers' lung can alter the metabolism of beta-carotene, that is, producing greater risk of cell alterations and neoplasias. It is probable that the alpha-tocopherol has beneficial effect on this association. Objective: To evaluate the participation of beta-carotene and alpha-tocopherol in the development of lung cancer induced by urethane and its relationship with cigarette exposition. Material and Method: Balb C mice were divided into 10 groups: G1(cigarette), G2 (cigarette and urethane), G3 (only urethane), G4, G5 and G6 (cigarette, urethane and beta-carotene to 0.25, 0.05 and 0.005%, respectively), G8 (urethane and beta-carotene to 0.25%), G7, G10 and G11 (cigarette, urethane and beta-carotene to 0.25 and alpha-tocopherol 0.25; 0.05 and 0.005%, respectively).The exposition to the cigarette was for 10 minutes, twice a day, 5 days a week, during 16 weeks. For induction of tumors, urethane was administered intraperitonealy, in the dose of 3.0mg/Kg. Nodules and hyperplasias were quantified; morphometric analyses of the nodules were performed. Kruskal-Wallis and of Mann-Whitney tests were used for statistical analysis. Results: Group G3 presented greater number of nodules (P=0.001), smaller stromal fraction (P=0.011) and greater sum of the tumor area (P=0.047) compared to group G2. Group G8 showed smaller number of nodules (P=0.013) and hyperplasias (P=0.05) compared to group G3. Both smaller doses of beta-carotene (G5 and G6) were statistically similar, although with smaller number of nodules when compared to group G4 (P=0.04). Group G4 presented smaller number of hyperplasias than G8, however, the number of nodules did not alter (P=0.045%). Stromal fraction of groups G3 and G4 was similar, although smaller than G2 and G5 (P=0.011). According to the alpha-tocopherol, the stromal fraction of group G7 was greater than the one of the groups G2, G3, G4 and G10 (P=0.011). The 0.25%-beta-carotene diet increased the area of the nodules, demonstrated by the largest area (P=0.03), smaller area (P=0.03), sum of the areas (P=0.018) and average of the areas (P=0.006) in group G4 when compared to G2. Conclusion: According to these results, it was concluded that passive tobacco can be a protecting factor in the evolution of tumors induced by urethane in mice, however, there is no evidence that this could be dose-dependent. The supplementation of beta-carotene in 0.25%-dose can also be a protecting factor, however, associated to passive tobacco it has smaller effect than in lower doses (0.05 and 0.005%). The exposition to cigarette smoke does not alter the number of nodules induced by urethane in mice when in the presence of 0.25%-beta-carotene diet; however the hyperplasia number with the presence of the cigarette diminished. The association of the alpha-tocopherol to the 0.25%- beta-carotene and the passive tobacco produces a protecting factor, mainly in the dose of 0.25%. / O hábito de fumar cigarros é responsável pela morte de milhões de pessoas por ano em todo o mundo, estando diretamente relacionado ao câncer de pulmão. Estudos demonstraram que maiores índices plasmáticos de beta-caroteno ou a grande ingestão de alimentos ricos em carotenóides diminuem o risco de desenvolver esta neoplasia. Por outro lado, existem estudos que sugerem que o pulmão de fumantes pode alterar o metabolismo do beta-caroteno, gerando maior risco de alterações celulares e neoplasias. É provável que o alfa-tocoferol tenha efeito benéfico sobre esta associação. Objetivo: Avaliar a participação do beta caroteno e do alfa-tocoferol no desenvolvimento de câncer de pulmão induzido por uretana e sua relação com a exposição ao cigarro. Material e Método: Camundongos Balb C foram
divididos em 10 grupos: G1(cigarro), G2(cigarro e uretana), G3 (uretana), G4, G5 e G6 (cigarro, uretana e beta-caroteno a 0,25; 0,05 e 0,005% respectivamente), G8 (uretana e Beta-caroteno a 0,25%), G7, G10 e G11 (cigarro, uretana e beta-caroteno a 0,25 e alfa-tocoferol a 0,25; 0,05 e 0,005% respectivamente). A exposição ao cigarro ocorreu durante 10 minutos, 2 vezes por dia, 5 dias por semana, por 16 semanas. Para a indução de tumores, foi administrada uretana por via intraperitoneal na dose de 3,0mg/Kg. Foram quantificados nódulos e hiperplasias, realizada análise morfométrica dos nódulos e submetidos aos testes de Kruskal-Wallis e de Mann-Whitney para análise estatística. Resultados: O grupo G3 apresentou maior número de nódulos (P=0,001), menor fração estromal (P=0,011) e maior soma da área de tumor (P=0,047) comparado ao grupo G2. O grupo G8, mostrou-se com menor número de nódulos (P=0,013) e hiperplasias (P=0,05) comparados ao grupo G3. As duas doses menores de beta-caroteno (G5 e G6) se mostraram estatisticamente semelhantes, porém com menor número de nódulos quando comparados ao grupo G4 (P=0,04). O grupo G4 apresentou menor número de hiperplasias que G8, porém o número de nódulos não se alterou (P=0,045). A fração estromal dos grupos G3 e G4 foram semelhantes, porém menores que G2 e G5 (P=0,011). Quanto ao alfa-tocoferol, a fração estromal do grupo G7 foi maior que a dos grupos G2, G3, G4 e G10 (P=0,011). A dieta com beta-caroteno a 0,25% aumentou a área dos nódulos, demonstrada pela maior área (P=0,03), menor área (P=0,03), soma das áreas (P=0,018) e média das áreas (P=0,006) no grupo G4 comparada com o grupo G2. Conclusão: Com estes resultados, concluiu-se que na evolução de tumores induzidos por uretana em camundongos o fumo passivo se comporta como um fator protetor, porém não há evidência de que seja dose-dependente. A suplementação de beta-caroteno na dose de 0,25% também age como protetor, porém associada ao fumo passivo tem efeito menor do que em doses mais baixas (0,05 e 0,005%). A exposição à fumaça do cigarro não altera o número de nódulos quando na presença de dieta com beta-caroteno a 0,25%, porém o número de hiperplasias com a presença do cigarro diminui. A associação do alfa-tocoferol ao beta-caroteno 0,25% e ao fumo passivo gera um fator protetor, principalmente na dose 0,25%.
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