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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Avaliação de técnicas cromatográficas acopladas a espectrometria de massas para análise de morfolina em manga / Evaluation of chromatographic techniques coupled to mass spectrometry for morpholine analysis in mango

Patricia Regina de Souza 15 April 2016 (has links)
A constante preocupação com o aumento do uso de agrotóxicos nas lavouras e os riscos gerados pelos resíduos destes compostos fazem com que os órgãos responsáveis pela fiscalização de alimentos no Brasil controlem a presença dessas substâncias nos produtos que chegam à mesa do consumidor. Atualmente, um dos grandes problemas na produção de alimentos é a utilização de substâncias proibidas em lavouras, muitas das quais não possuem estudos nem limites máximos de resíduos (LMR) estabelecidos, assim como a utilização de substâncias já registradas, mas em quantidades ou métodos de manejo incorretos. Ambos os casos podem resultar em sérios problemas à saúde humana. O objetivo deste estudo foi a avaliação da determinação de morfolina em amostras de manga utilizando técnicas como a Extração em Fase Sólida e a Cromatografia Gasosa acoplada à Espectrometria de Massas (SPE-GC-MS), assim como a Microextração em Sorvente Empacotado e Cromatografia Gasosa acoplada à Espectrometria de Massas (MEPS-GC-MS). Um segundo objetivo deste estudo consistiu em desenvolver, validar e avaliar uma metodologia analítica capaz de identificar quantitativamente a morfolina em amostras de manga por Cromatografia Líquida de Ultra Eficiência acoplada a Espectrometria de Massas em tandem (UHPLC-MS/MS). Para análise por GC-MS fez-se necessária a etapa de derivatização do analito, de forma que o mesmo aumentasse sua volatilidade e diminuísse a polaridade. A comparação entre as técnicas SPE e MEPS não foi possível devido ao efeito de matriz causado pela contaminação do liner e da coluna cromatográfica. Já a metodologia validada por UHPLC-MS/MS seguiu os critérios exigidos pelo Manual de Garantia da Qualidade Analítica, do Ministério da Agricultura Pecuária e Abastecimento (MAPA). O método foi aplicado em mangas de diferentes variedades obtidas no comércio local. Não foram encontrados resíduos de morfolina em nenhuma das amostras investigadas, de acordo com a metodologia proposta. Os resultados apresentados neste trabalho estabelecem metodologias eficientes, rápidas e de baixo custo na determinação de morfolina em amostras de manga. / The recurrent increasing of the use of pesticides on crops and the consequent risks due the exposure to chemical residues have urged the food regulation agencies to control the levels of these substances in products that reach consumer\'s table. A major problem nowadays for the production of food is the use of banned substances in crops and the extrapolation of the limit dosages of substances, which may result in serious problems to human health. Furthermore, many of these substances commonly used in crops still lack substantial information about the maximum residue levels (MRLs). The aim of this study was the evaluation of morpholine levels in mango samples using distinct techniques such as Solid Phase Extraction followed by Gas Chromatography coupled to Mass Spectrometry (SPE-GC-MS) and Microextraction by Packed Sorbent followed by Gas Chromatography Mass Spectrometry (MEPS-GC-MS). Another main goal of this work is the development, validation and evaluation of an analytical methodology to identify and quantitfy the presence of morpholine in mango samples, using Ultra-High Performance Liquid Chromatography coupled to tandem Mass Spectrometry (UHPLC-MS/MS). For the analysis of samples by GC-MS, it was required an initial step of derivatization of the analyte, in order to increase its volatility and reduce polarity. The comparison between SPE and MEPS techniques could not be performed due to matrix effects caused by contamination of the liner and the chromatographic column. On the other hand, the validated methodology for UHPLC-MS/MS presented herein followed all requirements proposed by the Analytical Quality Assurance Manual, accordingly to the Ministry of Agriculture, Livestock and Food Supply from Brazil. This method was applied in mango sample belonging to a wide variety of species found in the city of São Carlos, SP. Nevertheless, no significant levels of morpholine residues were found in any of the samples. In this work, we established a methodology efficient, fast and low cost for the determination of morpholine in mangos.
72

The Evolution and Domestication Genetics of the Mango Genus, Mangifera (Anacardiaceae)

Warschefsky, Emily 27 April 2018 (has links)
Domesticated species are vital to global food security and have also been foundational to the formulation and advancement of evolutionary theory. My dissertation employs emerging molecular genomic tools to provide an evolutionary context for crop improvement. I begin by providing a contemporary perspective on two components of domestication biology that have long been used to improve crop production: wild relatives of crop species and grafted rootstocks. First, I propose a method to systematically introgress crop wild relative diversity into crop breeding programs. Then, I explore rootstocks, the lesser-known half of the perennial crop equation, documenting prevalence and diversity, cataloging rootstock traits under selection, and discussing recent advances in rootstock biology. Both crop wild relatives and rootstocks remain largely underutilized resources and hold great promise for agricultural innovation. While humans have domesticated thousands of plant species, research has largely focused on annual crops, to the exclusion of perennials. To improve our understanding of how tree species respond to domestication, I examine the evolution and domestication of one of the world’s most important perennial tropical fruit crops, the mango, Mangifera indica, and its wild and semi-domesticated relatives. I generated a dataset suitable for studying Mangifera across evolutionary time using double digest restriction site associated DNA sequencing (ddRADseq). I present a multilocus phylogeny that informs the classification of Mangifera and reveals, for the first time, the evolutionary relationships of wild, semi-domesticated, and domesticated species in the genus. Narrowing my focus to the intraspecific level, I examine how the introduction of M. indica into regions of the world impacted its genetic diversity. My results show M. indica maintained high levels of genetic diversity during its introduction into the Americas. However, the novel diversity I detect in Southeast Asian mango cultivars suggests that M. indica has a more complex domestication history than previously assumed. I also find evidence that M. indica hybridized with multiple congeners following its introduction into Southeast Asia, forming two hybrid lineages that may be maintained by clonal polyembryonic reproduction. Collectively, my research provides a comprehensive framework for understanding the evolution and domestication of a tropical tree crop of global economic importance.
73

Creating High Fat Emulsions with Mango, Rapeseed Oil and Soy Lecithin

Svensson, Dag January 2013 (has links)
Food inevitably plays a vital role in our lives and is of great importance to our health and wellbeing. With increasing age, it is equally important to achieve adequate nutrition to prevent and alleviate age-related diseases. One problem is that far too many older adults find it difficult to eat enough nutritious food which in the long term may lead to malnutrition. With an increasing life expectancy the older population is growing and the problem with malnutrition is of great concern. Malnutrition can be caused by many different factors which make it difficult to find a single unique solution to the problem. Oral nutritional supplementation is one approach which has proved to be useful for improving the nutritional intake. This paper examines the possibility of creating high fat fruit emulsion with mango puré, rapeseed oil and lecithin, using simple blending equipment.  The puré-like products were evaluated for emulsion stability by a storage test, oil droplet size by a light microscope and light scattering device, viscosity by a viscometer, sensory properties by Flavoring profiling. Furthermore the nutritional values were calculated.  Successful emulsions were created using up to 50 g/100g rapeseed oil with adequate emulsion stability without lecithin. The energy content of the highest fat emulsion was 475kcal/100g. The quantities of lecithin used in these products reduced the oil droplet size but lowered the emulsion stability perhaps by depleting the stabilizing effect of mango originated particles. The lecithin made the product more viscous, also the oily and creamy/Rich mouth-feel were perceived higher with increasing lecithin. In these products and with the quantities used the lecithin was redundant. Further development of similar products but with addition of protein and perhaps sugar, to enhance flavor, should be of high interest.
74

A farm-level economic impact analysis of food safety and quality systems in the South African mango and litchi industry

Breedt, Vicky-Lohanzi. January 2009 (has links)
Thesis (M.Com.(Agricultural Economics))--University of Pretoria, 2009. / Includes bibliographical references
75

Influence of Mango secondary metabolites on Procontarinia infestation

Augustyn, Wilhelmina Agnes. January 2011 (has links)
D. Tech. Chemistry. / Discusses the extent of mango cultivar susceptibility to gall fly infestation can be predicted by the composition of secondary metabolites produced by the tree.
76

Alk(en)ylresorcinols in mango (Mangifera indica L.) and cereals studies into structure, anti-inflammatory activity, and use as marker compounds in authenticity control

Knödler, Matthias January 2009 (has links)
Zugl.: Hohenheim, Univ., Diss., 2009
77

Desenvolvimento, validação e aplicação de metodologias para determinação de resíduos de agrotóxicos em manga por SPME-GC-MS e SPME-HPLC-UV-Vis

Menezes Filho, Adalberto 26 March 2010 (has links)
Submitted by Ana Hilda Fonseca (anahilda@ufba.br) on 2016-09-06T15:39:12Z No. of bitstreams: 1 Tese Adalberto Menezes Filho 26.03.2010.pdf: 4529406 bytes, checksum: 23a6a27845c477df8cc06bee3255777f (MD5) / Approved for entry into archive by Vanessa Reis (vanessa.jamile@ufba.br) on 2016-09-08T10:44:55Z (GMT) No. of bitstreams: 1 Tese Adalberto Menezes Filho 26.03.2010.pdf: 4529406 bytes, checksum: 23a6a27845c477df8cc06bee3255777f (MD5) / Made available in DSpace on 2016-09-08T10:44:55Z (GMT). No. of bitstreams: 1 Tese Adalberto Menezes Filho 26.03.2010.pdf: 4529406 bytes, checksum: 23a6a27845c477df8cc06bee3255777f (MD5) / CNPq / Foram desenvolvidas, validadas e aplicadas duas metodologias analíticas por SPME e análise por GC-MS e HPLC-UV-Vis, para determinar resíduos de agrotóxicos em manga. 14 compostos foram analisados por GC-MS (clofentezina, carbofuran, diazinon, parationa, malationa, fentiona, tiabendazol, imazalil, bifentrina, permetrina, procloraz, piraclostrobina, difenoconazol, azoxistrobina) e 10 por HPLC-UV-Vis (tiabendazol, carbofuran, azoxistrobina, procloraz, fentiona, clofentezina, permetrina, abamectina, carbosulfan e bifentrina). Diferentes parâmetros que influenciam na eficiência da extração foram avaliados (Tipo de fibra, modo de extração, temperatura e tempo de extração e dessorção, velocidade de agitação e força iônica). Os melhores resultados foram obtidos com fibra de PA e DI a 50°C por 30 min, com agitação a 250 rpm e dessorção por 5 min a 280°C no GC- MS e no modo estático por 15 min na interface SPME-HPLC. Na validação foram avaliados o efeito da matriz, a linearidade das curvas analíticas, LOD, LOQ, precisão e exatidão. O método por SPME-GC-MS apresentou linearidade entre 3,3 e 1665,0 µg kg-1, LOD entre 1,0 e 3,3 µg kg-1 e LOQ entre 3,3 e 33,3 µg kg-1. O método por SPME-HPLC- UV-Vis apresentou linearidade entre 2,0 e 250,0 µg kg-1, LOD entre 0,6 e 3,3 µg kg-1 e LOQ entre 2,0 e 10,0 µg kg-1. Nos dois métodos foram obtidos CV menores que 20%. Os métodos foram aplicados na análise de amostras coletadas em Salvador-BA e Aracaju-SE. Nas amostras de Salvador foram detectados resíduos de sete compostos e nas de Aracaju resíduos de cinco compostos. Entretanto, as concentrações estavam abaixo dos valores estabelecidos pela Legislação Brasileira. / Were developed, validated and applied two analytical methodologies by SPME and GC-MS and HPLC-UV-Vis analysis to determine pesticide residues in mango. 14 compounds were analyzed by GC-MS (clofentezine, carbofuran, diazinon, methyl parathion, malathion, fenthion, thiabendazole, imazalil, bifenthrin, permethrin, prochloraz, pyraclostrobin, difenoconazole, azoxystrobin) and 10 for HPLC-UV-Vis (thiabendazole, carbofuran, azoxystrobin, prochloraz, fenthion, clofentezine, permethrin, abamectin, bifenthrin and carbosulfan). Different parameters influencing the extraction efficiency were evaluated (fiber type, extraction mode, temperature, extraction and desorption times, stirring velocities and ionic strength. The best results were obtained using PA fiber and DI mode at 50°C form 30 min, along with stirring at 250rpm and desorption for 5 min at 280°C in the GC-MS and estatic mode for 15 min in the SPME-HPLC interface. For validation, we assessed the matrix effect, the linearity of calibration curves, LOD, LOQ, precision and accuracy. The method for SPME-GC-MS showed linearity between 3.3 and 1665.0 mg kg- 1, LOD between 1.0 and 3.3 µg kg-1 and LOQ between 3.3 and 33.3 µg kg-1. The method for SPME-HPLC-UV-Vis showed linearity between 2.0 and 250.0 µg kg-1, LOD between 0.6 and 3.3 µg kg-1 and LOQ between 2.0 and 10.0 µg kg-1. In both methods were obtained CV below 20%. The methods were applied in the analysis of samples collected in Salvador- BA and Aracaju-SE. In samples from Salvador seven compounds residues were detected and in samples from Aracaju five compounds residues were detected. However, the concentrations were below the values established by Brazilian legislation
78

Aplicação de biofilmes em pré-colheita para o controle da injúria provocada pelo látex em frutos de Mangifera indica L. (Anacardiaceae) / The biofilm application in preharvest to control sapburn injury on fruits of Mangifera indica L. (Anacardiaceae)

Oliveira, Marcos Nunes de 21 December 2005 (has links)
The mango plants produce one of more popular eatable fruits in the world, it is having important participation at economy of several countries. The variety more cultivated in Brazil is Tommy Atkins , that represent 79 % of the planted area. The main producer is Northeast region (53% of the total production in Brazil), where the São Francisco Valley is distinguished; it is considerate the Brazilian El Dorado of the production and exportation of mango. The incidence of mechanical injury is one of main problems that affect the quality of the fruits of mango plants; the sapburn injury caused by latex is between them. The objective this work was verify the effect of bio film application of carnauba wax and cassava starch in preharvest: (1) in the control of injury caused by latex on fruits of the mango plants during the harvest and (2) the maintenance of the physicochemical characteristic of the fruit flesh storage in refrigeration. The formulas of carnauba wax (0%, 5%, 10% and 15%) and cassava starch (0%, 2%, 4% and 6%) were applied in preharvest (2 hours before), on fruits of mango when they were on the mother plant, by one spray, to assure the bio film formation. After that the fruits were cropped with less 1 cm of stem to permit the flow of latex on them and they were clean utilizing water with 1,5% chlorine and 1,5% of detergent and submitted the evaluation of injury by latex and the destructive analyses (pH, Total Soluble Solids and Total Titrable Acidity) and non-destructive (Fresh Mass Loss). The fruits were maintained in refrigeration 10ºC (±) 2ºC of temperature and 85% (±) 5% of UR. The analyses were replicated in 10 and 20 days of the fruit storage. The completely randomized design was utilized with 3 replicates per treatment in 2 experiments: carnauba wax and cassava starch. The results showed that carnauba wax influenced the behaviour of pH and Fresh Mass Loss and the cassava starch influenced in the Fresh Mass Loss. It was still verified that with big concentration of cassava starch the index of injury by latex was small and the carnauba wax not done satisfactory effect in the injury reduction. / A mangueira produz uma das frutas comestíveis mais populares do mundo, tendo participação importante na economia de vários países. No Brasil, a variedade mais cultivada é a Tommy Atkins , representando 79% da área plantada. O Nordeste é a principal região produtora (53% do total produzido no Brasil), destacando-se o Vale do São Francisco, considerado o eldorado brasileiro da produção e exportação de manga. Um dos principais problemas que afeta qualitativamente os frutos da mangueira é a incidência de injúrias mecânicas e, dentre essas, a queima por látex. Assim, o objetivo deste trabalho foi o de se verificar o efeito da aplicação em précolheita de biofilmes de cera de carnaúba e de fécula de mandioca: (1) no controle da injúria provocada pelo látex nos frutos da mangueira no momento da colheita e (2) na manutenção das características físico-químicas da polpa dos frutos armazenados sob refrigeração. As formulações de cera de carnaúba (0%, 5%, 10% e 15%) e de fécula de mandioca (0%, 2%, 4% e 6%) foram aplicadas, em précolheita (2 horas antes da colheita), sobre os frutos de manga ainda na planta-mãe, através de um borrifador, para garantir a formação do biofilme. Em seguida os frutos foram colhidos com menos de 1 cm de pedúnculo para permitir o escorrimento do látex sobre eles e, após higienização com água contendo 1,5% de cloro e 1,5% de detergente, foram realizadas, além da avaliação da injúria por látex, as análises destrutivas (pH, sólidos solúveis totais e acidez total titulável) e não-destrutivas (perda de massa fresca). Os frutos foram mantidos sob refrigeração a 10°C± 2°C de temperatura e 85% ± 5% de UR. As análises foram repetidas aos 10 e 20 dias de armazenamento dos frutos. Utilizou-se o delineamento inteiramente casualizado com 3 repetições por tratamento em 2 experimentos: cera de carnaúba e fécula de mandioca. Os resultados demonstraram que a cera de carnaúba influenciou no comportamento do pH e da PMF e, a fécula de mandioca influenciou na PMF. Também verificou-se que quanto maior a concentração de fécula de mandioca menor foi o índice de injúria por látex e que a cera de carnaúba não exerceu efeito satisfatório na redução da injúria.
79

Efeitos das barreiras não tarifárias nas exportações de manga in natura.

Costa, Luana Gonçalves Euclydes Borges da 27 October 2006 (has links)
Made available in DSpace on 2016-06-02T19:51:23Z (GMT). No. of bitstreams: 1 DissLGEBC.pdf: 972232 bytes, checksum: 9a8115b314938fa8bc8a979555f4ed85 (MD5) Previous issue date: 2006-10-27 / The fruit sector is found in expansion, being considered one of the fastest emerging and potential in the Brazilian agribusiness. The fruit chain has been affected by the increase in global competitiveness, where the big producers and retailers, focusing on the strengthening of their competitive position have amplified their strategies and acquisitions leading to a greater market concentration, a greater asymmetry of power and more complex configuration of this chain worldwide. The mango is in the spotlight in the Brazilian fruit culture, it is the third best exported fruit (113 thousand tons) in 2005. Brazil was eighth in worldwide production of mango in 2005, producing 850.000 tons. The northeast was the main productive area, responsible for 66% of all national production. The fruit sector is strongly affected by non-tariff barriers (NTBs), especially technical and phytosanitary. The restrictions have represented serious obstacles to the Brazilian fruit culture expansion in the international market. Therefore, the general goal of this research was analyze the productive chain of the exported Brazilian mango, focusing on the imposition of non-tariff barriers in the production, harvest, post harvest and distribution of national producers of mango in natura, where the study of case was selected as a more adequate method for the research and thus as multicase study was carried through. Some results found stand out: the technical barriers (having a phytosanitary state) are more frequent in mango exportation; the fruit is sold indirectly; the agriculture practice and non-tariff barriers are interrelated and finally, the consume behavior in different markets and consumers interfere in the process and practices adopted by the producers. / O setor frutícola encontra-se em expansão, sendo considerado um dos setores de maior potencial do agronegócio brasileiro. A cadeia de frutas tem sido afetada pelo aumento da competitividade global, onde as grandes empresas produtoras de frutas e as redes varejistas, visando ao fortalecimento de suas posições competitivas, têm ampliado suas estratégias de fusões e aquisições conduzindo à maior concentração de mercado, à maior assimetria de poder e à configuração mais complexa dessa cadeia em nível mundial. A manga ocupa um lugar de destaque na fruticultura brasileira, sendo a terceira fruta mais exportada (113 mil toneladas) em 2005. O Brasil ocupou a oitava posição na produção mundial de manga em 2005, produzindo 850.000 toneladas, sendo o nordeste a principal região produtora, responsável por 66% da produção nacional. O setor frutícola é fortemente afetado por barreiras não-tarifárias (BNT´s), especialmente de caráter técnico e fitossanitários. Tais restrições têm representado sérios entraves à expansão da fruticultura brasileira no mercado internacional. Sendo assim, o objetivo geral dessa pesquisa foi analisar a cadeia produtiva da manga brasileira para exportação, tendo como foco os efeitos da imposição de barreiras não-tarifárias nas práticas de produção, colheita, pós-colheita e distribuição dos produtores nacionais de manga in natura, onde elegeu-se o estudo de caso como método mais adequado para a pesquisa e foi realizado um estudo multicaso. Dentre os resultados encontrados destacam-se: as barreiras técnicas (de caráter fitossanitário) são a de maior incidência nas exportações de manga; a fruta é comercializada de forma indireta; as práticas agrícolas e as barreiras não-tarifárias estão inter-relacionadas e por fim, o comportamento de consumo dos diferentes mercados e consumidores interferem nos processos e práticas adotadas pelos produtores.
80

Capacidade antioxidante, efeitos anticarcinogênicos e absorção de polifenóis de de manga (Mangifera indica L.) in vitro / Antioxidant capacity, anticancer effects and absorption of mango (Mangifera indica L.) polyphenols in vitro

Bertoldi, Michele Corrêa 09 December 2009 (has links)
Made available in DSpace on 2015-03-26T12:24:56Z (GMT). No. of bitstreams: 1 texto completo.pdf: 2107014 bytes, checksum: a646700aff1c3e6a44a344a0051aa176 (MD5) Previous issue date: 2009-12-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Polyphenols found in mango pulp, including gallotannins, flavonol glycosides, gallic acid, benzophenone derivatives and mangiferin have shown anticancer activity. Biological activities of polyphenols have been related to their bioavailability. Deglycosylation by β-glucosidases is a critical step in the metabolism and absorption of dietary polyphenols in humans, which might influence their anticancer properties. The objective of this study was to elucidate the anti-cancer effects of mango polyphenols of several varieties (Francis, Kent, Ataulfo, Tommy Atkins and Haden) in different types of cancer. The antiproliferative effects of mango polyphenols were studied in vitro using different cancer cell lines including Molt-4 leukemia, A-549 lung, MDA-MB-231 breast, LnCap prostate, SW-480 colon cancer cells and the non-cancer colon cell line CCD-18Co. Molecular mechanisms involved on the anti-cancer activities of mango polyphenols were assessed. The effect of mango polyphenols on gene expression, cell cycle regulation and reactive oxygen species production on colon cancer cells SW-480 were investigated by RT-PCR, flow cytometry and fluorescence intensity measurement, respectively. The effect of the hydrolysis of mango polyphenols with β-glucosidase on their antioxidant activity, cancer cell-growth suppression activity and in vitro intestinal absorption through human colon adenocarcinoma Caco-2 cell monolayers was evaluated. In addition, the antiproliferative effect of high and low molecular weight polyphenols rich-fractions on colon (SW-480) and breast (MDA-MB-231) cancer cells was studied. Cell lines were incubated with Ataulfo and Haden phenolic extracts, which were selected based on their superior antioxidant capacity compared to the other varieties. Ataulfo and Haden polyphenols inhibited the growth of all human cancer cell lines. SW-480 (colon cancer), MOLT-4 (leukemia) and MDA-MB-231 (breast-cancer) were statiscally equally most sensitive to Ataulfo, whereas SW-480 and MOLT-4 were the most sensitive cell lines to Haden, as determined by cell counting. The efficacy of phenolic extracts from all mango varieties in inhibiting cell growth was tested on SW- 480 colon carcinoma cells. Ataulfo and Haden demonstrated superior efficacy, followed by Kent, Francis and Tommy Atkins. At 5 mg GAE/L, Ataulfo inhibited the growth of colon SW-480 cancer cells by ~79% while the growth of non-cancer colonic myofibroblasts CCD-18Co cells was not inhibited. The growth inhibition exerted by Ataulfo and Haden polyphenols on SW-480 cells was associated with an increased mRNA expression of pro-apoptotic biomarkers (caspase 8, Bax and Bim) and cell cycle regulators (PKMYT1), cell cycle arrest and an alteration in the generation of reactive oxygen species. Phenolic extracts from mango pulp contained gallic acid, mangiferin, phenolic acid derivatives and gallotannins, which were characterized by HPLC-DAD and HPLC-ESI-MSn analysis before and after enzymatic hydrolysis (0.17 mg β- glucosidase 1000 KU/g mango pulp/ 4 h / 35°C). Phenolic acids including gallic, caffeic, ferulic, p-coumaric and p-hydroxybenzoic acids consisted the main compounds derived from enzymatic hydrolysis. Caco-2 cell monolayers were incubated for 2h on the apical side with hydrolyzed and non-hydrolyzed mango extracts. Gallic, caffeic, ferulic, p-coumaric, vanillic and p-hydroxybenzoic acids were detected on the basolateral side for hydrolyzed extract but only gallic acid was detected for the nonhydrolyzed extract. High molecular weight polyphenols, mangiferin and gallotannins, were not transported. Mango pulp polyphenols (control) from all varieties inhibited the proliferation of HT-29 colon (0-27 μg of gallic acid equiv/mL) and MDA-MB-231 breast (0-24 μg GAE/ mL) human cancer cells by up to 99.8 and 89.9 %, respectively. Despite enhanced absorption facilitated by enzymatic hydrolysis, a significant increase in antioxidant activity, phenolic content and antiproliferative effects on breast and colon cancer cells was not observed. Additionally, both high (422; 788-1852 Da) and low (138-194 Da) molecular weight polyphenols rich-fractions equally inhibited cell proliferation of colon and breast cancer cells at the same extent (0-20 μg of gallic acid equiv/mL), which may indicate that the anti-cancer efficacy of mango polyphenolics is not dependent on enzymatic hydrolysis. These results corroborate previous findings from in vivo studies, which suggest that the most of mango polyphenols are not absorbed intact through the small intestine, but may be hydrolyzed by intestinal enzymes into low molecular weight aromatic acids, which would be later absorbed; or when polyphenols are not absorbed, they likely reach the large intestine, modulating the gut microflora, and thus they contribute to reduce the risk of colon carcinogenesis. Overall, polyphenols from several mango varieties exerted anti-cancer effects, and these effects may not require enzymatic hydrolysis by β-glucosidase. / Polifenóis presentes em polpa de manga, incluindo galotaninos, glicosídeos de flavonóides, ácido gálico, derivados da benzofenona, e mangiferina, têm demonstrado propriedades anticarcinogênicas. A etapa de deglicosilação por β-glicosidases tem se mostrado necessária ao metabolismo e à absorção de polifenóis derivados da dieta pelo organismo humano, o que poderia influenciar suas propriedades anticarcinogênicas. O objetivo deste estudo foi elucidar os efeitos anticarcinogênicos de polifenóis extraídos da polpa de manga de diferentes variedades (Francis, Kent, Ataulfo, Tommy Atkins e Haden) em diferentes tipos de câncer. Os efeitos antiproliferativos de polifenóis de manga foram estudados utilizando modelos in vitro de cultura de células cancerosas, incluindo as linhagens celulares de câncer humano Molt-4 (leucemia), A-549 (câncer de pulmao), MDA-MB-231 (câncer de mama), LnCap (câncer de próstata), SW-480 (câncer de colón) e células de colón não cancerosas CCD-18Co. Os mecanismos moleculares envolvidos nas propriedades anticarcinogênicas de polifenóis de manga foram investigados. O efeito do tratamento com polifenóis na expressão gênica, na regulação do ciclo celular e na produção de espécies reativas de oxigênio em células cancerosas de colón humano SW-480 foi investigado por RT-PCR, citometria de fluxo e quantificação da intensidade de fluorescência, respectivamente. Além disso, o efeito da hidrólise de polifenóis de manga pela enzima β-glicosidase na atividade antioxidante, na supressão do crescimento tumoral e na absorção intestinal in vitro através da monocamada de células de adenocarcinoma de colón humano Caco-2 foi avaliado. Ademais, o efeito antiproliferativo de frações fenólicas enriquecidas com polifenóis de baixo e elevado peso molecular em células cancerosas de colón (SW-480) e mama (MDA-MB-231) foi estudado. Células cancerosas foram tratadas com extratos fenólicos das variedades Ataulfo e Haden, as quais foram selecionadas em razão da maior capacidade antioxidante quando comparada a outras variedades. Polifenóis de Ataulfo e Haden inibiram o crescimento de todas as linhagens celulares. SW-480 (câncer de cólon), MOLT-4 (leucemia) e MDA-MB-231 (câncer de mama) apresentaram igualmente maior sensibilidade ao tratamento com polifenóis de Ataulfo, enquanto SW- 480 e MOLT-4 mostraram-se mais sensíveis ao tratamento com polifenóis de Haden, segundo resultados obtidos por contagem de células. O efeito antiproliferativo dos extratos fenólicos de todas as variedades de manga foi avaliado em células cancerosas de colón humano (SW-480). As variedades Ataulfo e Haden demonstraram maior efeito supressor, seguidas de Kent, Francis e Tommy Atkins. Quando células cancerosas de colón SW-480 foram tratadas com 5 mg GAE/L de polifenóis de Ataulfo, o crescimento celular foi inibido em ~79%, enquanto a proliferação de miofibroblastos não cancerosos CCD-18Co não foi inibida. A supressão do crescimento celular pelo tratamento com polifenóis de Ataulfo e Haden em células de câncer de colón SW-480 foi associada com o aumento na expressão gênica de biomarcadores de apoptose (caspase 8, Bax e Bim) e reguladores do ciclo celular (PKMYT1), atraso do ciclo celular e alteração na produção de espécies reativas de oxigênio. Os extratos fenólicos da polpa de manga continham ácido gálico, mangiferina, derivados de ácidos fenólicos e galotaninos, os quais foram caracterizados por análises em HPLC-DAD e HPLC-ESI-MSn antes e após a hidrólise enzimática (0.17 mg β-glicosidase 1000 KU/g polpa de manga / 4 h / 35°C). Ácidos fenólicos incluindo ácido gálico, caféico, ferúlico, p-coumárico e p-hidroxibenzóico consistiram os principais compostos derivados da hidrólise enzimática. Monocamadas de células Caco-2 foram incubadas por 2h no compartimento apical com extratos controle e hidrolisado. Quando incubadas com o extrato hidrolisado, ácido gálico, caféico, ferúlico, p-coumárico, vanílico e p-hidroxibenzóico foram detectados no compartimento basolateral, enquanto apenas ácido gálico foi detectado quando as células foram tratadas com o extrato controle. Polifenóis de elevado peso molecular, incluindo mangiferina e galotaninos, não foram transportados. Polifenóis de polpa (controle) de todas as variedades inibiram a proliferação de células humanas de câncer de colón HT-29 (0-27 μg de ácido gálico equiv./mL) e de mama MDA-MB-231 (0-24 μg GAE/mL) em até 99.8 e 89.9 %, respectivamente. Apesar da hidrólise enzimática ter aumentado a absorção de polifenóis de manga, não houve aumento significativo na atividade antioxidante, no conteúdo fenólico e na supressão do crescimento de células cancerosas de colón e mama. Ademais, ambas as frações fenólicas enriquecidas com polifenóis de baixo (138-194 Da) e elevado (422; 788-1852 Da) peso molecular inibiram o crescimento de células cancerosas de colón e mama na mesma extensão (0- 20 μg GAE/mL), o que poderia indicar que a atividade anticarcinogênica de polifenóis de manga seria independente da hidrólise enzimática. Estes resultados corroboram resultados obtidos em estudos in vivo, que sugerem que a grande parte dos polifenóis não seriam absorvidos em sua forma intacta através do intestino delgado, mas poderiam ser hidrolisados por enzimas intestinais em ácidos aromáticos de baixo peso molecular, os quais seriam posteriormente absorvidos; ou ainda, quando não absorvidos, poderiam, alcançar o intestino grosso, modulando a microflora intestinal e, desta forma, contribuiriam para reduzir o risco de câncer de cólon. Desta forma, polifenóis de polpa de manga de diferentes variedades exibiram efeitos anticarcinogênicos em modelos de cultura de células, os quais poderiam não ser necessariamente dependentes da hidrólise enzimática pela β-glicosidase.

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