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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.
31

Pest Management of Japanese Beetle (Coleoptera: Scarabaeidae) and a Study of Stink Bug (Hemiptera: Pentatomidae) Injury on Primocane-bearing Caneberries in Southwest Virginia

Maxey, Laura Michele 29 April 2011 (has links)
Field experiments (2007-2009) and laboratory bioassays (2009) tested the efficacy of insecticides with short pre-harvest intervals, caneberry cultivar susceptibility, and geranium toxicity for reducing Japanese beetle (JB) activity on primocane-bearing caneberries. Deltamethrin, chlorantraniliprole, bifenthrin, lime-alum, and thyme oil reduced JB activity in the field. Deltamethrin, chlorantraniliprole, acetamiprid, an azadirachtin and pyrethrin mixture, an azadirachtin and neem oil extract mixture, and an extract of Chenopodium ambrosioides reduced JB activity during the bioassays. "Prelude" had significantly more JB than "Anne", "Caroline", "Heritage", "Dinkum", or "Himbo Top" and "Prime-Jan" had significantly more JB than "Prime-Jim". Compared to certain cultivars, "Heritage", "Caroline", "Himbo Top", and "Prime-Jan" had higher percentages of injured fruit and "Autumn Bliss", "Heritage", and "Caroline" produced greater marketable and overall yields. "Prime-Jan" produced more overall yield than "Prime-Jim"; marketable yields from both blackberry cultivars were similar. Defoliation was significantly less for "Dinkum", "Caroline", "Heritage", and "Anne" than for "Prelude" in 2008 and significantly less for "Caroline" and "Anne" than "Prelude" or "Fall Gold" in 2009. In field tests, previous consumption of geraniums lessened raspberry defoliation by JB. Bioassays indicated that JB activity was only reduced if JB were continually exposed to geranium. Therefore, the efficacy of geranium as a trap crop for JB may be limited. The stink bug species within the caneberries were identified (2008-2009) and Euschistus servus (Say) made up 48.1 % of the overall species composition. Stink bug injury to ripening raspberries was identified as small holes between drupelets; stink bug excretions also ruined fruit. / Master of Science in Life Sciences
32

Work/Life Balance and Smartphones: Can a Smartphone make a difference?

Bomber, Kristin January 2010 (has links)
<p>This thesis examines the relationship between work/life balance and Smartphones (Blackberry, iPhone, Android etc.)</p><p>Academic research has areas where not much research has been done previously including the qualitative research on work/life balance, positive crossover of work/life balance, newness of Smartphone technology, and consequences of constant connectivity. This study hopes to eliminate some of the gaps in these areas of research and proposes two research questions:  <strong>So what does owning a Smartphone mean for work life and home life?  Most importantly can this phone help people towards or assist with the balance they are so looking for or do the phones not impact this balance and just assist in the work life and home life realms separately?</strong></p><p>A qualitative approach using constructionist and interpretivist views were used to conduct the research. Empirical material was collected during phone interviews with participants in the USA, while supporting material was gathered from conference papers, academic articles, websites, and textbooks.</p><p>There are two major themes within this paper, work/life balance and Smartphone technology. For work/life balance a common understanding was reached that work and personal life should be kept happy but that doesn’t mean equal.  Also discussed is research about people that put up boundaries in their lives to try and separate things, one group of people likes to have work and personal separate but one group likes them combined.  Research also presents that there are consequences for setting up boundaries but that having the ability to choose where these boundaries are makes for a much happier situation.  On the technology side of research there is support for these devices being used to manage people’s different selves through communication from being more connected to people to feeling left out when the technology is not there. Also mentioned is how people adapt the devices to fit new and unique situations that the devices may not have been intended to be used for.</p>
33

Efeitos do consumo materno e/ou paterno de extrato de amora-preta (Rubus spp.) na suscetibilidade da prole feminina à carcinogênese mamária quimicamente induzida / Blackberry (Rubus spp.) extract maternal and/or paternal consumption effects on female offspring susceptibility to chemically-induced breast carcinogenesis.

Pires, Vanessa Cardoso 18 May 2016 (has links)
O câncer de mama é o segundo tipo de neoplasia mais prevalente no mundo e o mais comum entre as mulheres. É descrito que o padrão de consumo alimentar materno e paterno está relacionado à suscetibilidade da prole ao desenvolvimento de doenças crônicas não transmissíveis, inclusive o câncer. A amora-preta é uma das frutas com maior conteúdo antioxidante e seus compostos bioativos possuem atividade antioxidante, anticarcinogênica e anti-inflamatória. Sendo assim, o presente trabalho propõe avaliar os efeitos do consumo materno e/ou paterno de extrato de amora-preta (Rubus spp.) na suscetibilidade da prole feminina ao desenvolvimento de neoplasias mamárias quimicamente induzidas. Para tanto, camundongos da linhagem C57BL/6 foram divididos aleatoriamente em 4 grupos: pai amora (PA), mãe amora (MA), pai e mãe amora (PMA) e controle (CTRL). Os pais receberam extrato de amora-preta logo após o desmame durante 8 semanas e as mães receberam o extrato durante a gestação e lactação. O extrato de amora-preta foi administrado na água de beber (0.84g de antocianinas/L) ad libitum. Os pais tratados com extrato de amora apresentaram redução na atividade enzimática da superóxido dismutase (SOD) e da catalase (CAT) no testículo (p<0.05 e p<0.001, respectivamente), aumento na capacidade antioxidante plasmática, na porcentagem de espermatozoides normais e na produção diária de espermatozóides em relação ao grupo controle (p<0.001 para todos). Além disso, os grupos PA, MA e PMA apresentaram aumento na taxa de prenhez (p<0.05) e redução da mortalidade perinatal (p<0.01, p<0.05 e p<0.001, respectivamente). Em relação à prole feminina não submetida à carcinogênese foi observada redução na capacidade antioxidante plasmática nos grupos PA (p<0.001) e MA (p<0.01), enquanto o grupo PMA apresentou aumento nesse parâmetro (p<0.001). No desenvolvimento da glândula mamária, houve aumento do desenvolvimento epitelial nos grupos PA, MA e PMA (p<0.001 para todos), de diferenciação nos grupos MA e PMA (p<0.01 para ambos) e da taxa de apoptose nos grupos MA e PMA (p<0.05), além de redução no número de TEBs nos grupos PA, MA e PMA (p<0.01, p<0.001 e p<0.001, respectivamente). Não foram observadas alterações significativas nas filhas submetidas à indução química da carcinogênese mamária por DMBA. Assim, é possível concluir que apesar de ter alterado o desenvolvimento da glândula mamária, o consumo materno e/ou paterno de extrato de amora-preta não foi capaz de impactar sobre a suscetibilidade da prole feminina à carcinogênese mamária quimicamente induzida. / Breast cancer is the second most prevalent type of cancer in the world and the most common among women. It is known that maternal and paternal food intake pattern are related to offspring susceptibility to non-communicable diseases, including cancer. Blackberry is one of the fruits with high antioxidant content and its compounds have antioxidant, anticarcinogenic and anti-inflammatory properties. So, the aim of the present study was evaluate the effects of maternal and/or paternal blackberry extract consumption on female offspring susceptibility to chemically-induced breast carcinogenesis. Thus, C57BL/6 mice were divided into 4 groups: father blackberry (FB), mother blackberry (MB), father and mother blackberry (FMB) and control (CTRL). Fathers received blackberry extract from weaning during 8 weeks and the mothers were treated during gestation and lactation. Blackberry extract was given in the drink water (0.84g anthocyanins/L) ad libitum. Fathers treated with blackberry had a reduction on superoxide dismutase (SOD) and catalase (CAT) activities in the testis (p<0.05 and p<0.001, respectivelly), an increase on plasmatic antioxidant capacity, percentage of normal sperm and daily sperm production in relation to control group (p<0.001 for all comparisons). Moreover, FB, MB and FMB groups had an increase of pregnancy rate (p<0.05) and a decrease of perinatal mortality (p<0.01, p<0.05 and p<0.001, respectively). Female offspring had a reduction of plasmatic antioxidant capacitity in FB (p<0.001) and MB (p<0.01) groups, while FMB group showed an increase in this parameter (p<0.001). On mammary gland development, it was observed higher epithelial development in FB, MB and FMB groups (p<0.001 for all comparisons), increased differentiation in MB and FMB groups (p<0.01 for both) and higher apoptosis rate in MB and FMB groups (p<0.05 for both), besides decreased TEBs number in FB, MB and FMB groups (p<0.01, p<0.001 and p<0.001, respectively). It was not found significant differences in the female offspring submitted to chemically-induced breast carcinogenesis. So, it is possible to conclude that in spite of maternal and/or paternal blackberry extract consumption changed the mammary gland development, it was not able to change the female offspring susceptibility to chemically-induced breast carcinogenesis.
34

Study of the health promoting properties of the tropical highland blackberry (Rubus adenotrichos) and the impact of digestion and pasteurization processes

Azofeifa, Gabriela 16 December 2013 (has links) (PDF)
This study evaluated biological activities of blackberries (Rubus adenotrichos) and the effects of digestion or pasteurization processes on these activities. The blackberries phenolic extract showed an ORAC value of 4339 ± 144 μM TE/g, higher than those of quercetin and ellagic acid. It also protected liposomes and liver homogenates against lipid peroxidation; with IC50 of 7.0 ± 0.5 and 20.3 ± 4.2 μg/mL, respectively. The blackberry polyphenols inhibited nitrite production in J774A.1 cells stimulated with LPS+IFNγ due to down-regulation of iNOS protein expression, suggesting an anti-inflammatory potential. The biological activities of the fruits could be affected by the industrial processes. The pasteurization of a blackberry juice caused a 7% decrease in the anthocyanins concentration of the highest temperature tested, 92 °C. For the same sample, a significant reduction of 27% and 15% were showed in the DPPH and NO scavenging capacity, respectively. However, non-significant differences were evident neither for the peroxidation inhibitory capacity nor for the intracellular antioxidant activity after the pasteurization step. The antioxidant capacity is largely dependent of their bioavailability and because of this a blackberry juice was digested in vitro to obtain samples that represent the major stages of the digestion process. The gastric digestion had slight impact on polyphenolic composition while the pancreatin/bile digestion had marked effects on polyphenolic composition, particularly in the ratio anthocyanins-ellagitannins. These changes in phenolic composition caused in the dialyzed fraction a reduction of 33% and 35% in the activity against nitrogen derived radicals DPPH and NO respectively. As well the capacity to inhibit intracellular ROS was decrease by an 85% in the dialyzed fraction. Nevertheless, no significant differences were evident in the capacity to inhibit lipid peroxidation. Finally, this study used an in vivo model with diabetic rats to evaluate the effect of the consumption of a blackberry beverage. The blackberry intake provoked a decrease in plasmatic glucose (-48.6%), triglycerides (-43.5%) and cholesterol (-28.6%) levels in the diabetic rats with respect to the diabetic controls animals. The diabetic rats which consumed blackberry, improved (+7%) the plasma antioxidant capacity (PAC) values and reduced the levels of lipid peroxidation in plasma (-19%) and in kidney tissue (-23%). This study suggests that selecting blackberry as a dietary complement could have health beneficial effects even when considering the bioavailability aspects of the phenolic compounds and the pasteurization effects.
35

Efeitos do consumo materno e/ou paterno de extrato de amora-preta (Rubus spp.) na suscetibilidade da prole feminina à carcinogênese mamária quimicamente induzida / Blackberry (Rubus spp.) extract maternal and/or paternal consumption effects on female offspring susceptibility to chemically-induced breast carcinogenesis.

Vanessa Cardoso Pires 18 May 2016 (has links)
O câncer de mama é o segundo tipo de neoplasia mais prevalente no mundo e o mais comum entre as mulheres. É descrito que o padrão de consumo alimentar materno e paterno está relacionado à suscetibilidade da prole ao desenvolvimento de doenças crônicas não transmissíveis, inclusive o câncer. A amora-preta é uma das frutas com maior conteúdo antioxidante e seus compostos bioativos possuem atividade antioxidante, anticarcinogênica e anti-inflamatória. Sendo assim, o presente trabalho propõe avaliar os efeitos do consumo materno e/ou paterno de extrato de amora-preta (Rubus spp.) na suscetibilidade da prole feminina ao desenvolvimento de neoplasias mamárias quimicamente induzidas. Para tanto, camundongos da linhagem C57BL/6 foram divididos aleatoriamente em 4 grupos: pai amora (PA), mãe amora (MA), pai e mãe amora (PMA) e controle (CTRL). Os pais receberam extrato de amora-preta logo após o desmame durante 8 semanas e as mães receberam o extrato durante a gestação e lactação. O extrato de amora-preta foi administrado na água de beber (0.84g de antocianinas/L) ad libitum. Os pais tratados com extrato de amora apresentaram redução na atividade enzimática da superóxido dismutase (SOD) e da catalase (CAT) no testículo (p<0.05 e p<0.001, respectivamente), aumento na capacidade antioxidante plasmática, na porcentagem de espermatozoides normais e na produção diária de espermatozóides em relação ao grupo controle (p<0.001 para todos). Além disso, os grupos PA, MA e PMA apresentaram aumento na taxa de prenhez (p<0.05) e redução da mortalidade perinatal (p<0.01, p<0.05 e p<0.001, respectivamente). Em relação à prole feminina não submetida à carcinogênese foi observada redução na capacidade antioxidante plasmática nos grupos PA (p<0.001) e MA (p<0.01), enquanto o grupo PMA apresentou aumento nesse parâmetro (p<0.001). No desenvolvimento da glândula mamária, houve aumento do desenvolvimento epitelial nos grupos PA, MA e PMA (p<0.001 para todos), de diferenciação nos grupos MA e PMA (p<0.01 para ambos) e da taxa de apoptose nos grupos MA e PMA (p<0.05), além de redução no número de TEBs nos grupos PA, MA e PMA (p<0.01, p<0.001 e p<0.001, respectivamente). Não foram observadas alterações significativas nas filhas submetidas à indução química da carcinogênese mamária por DMBA. Assim, é possível concluir que apesar de ter alterado o desenvolvimento da glândula mamária, o consumo materno e/ou paterno de extrato de amora-preta não foi capaz de impactar sobre a suscetibilidade da prole feminina à carcinogênese mamária quimicamente induzida. / Breast cancer is the second most prevalent type of cancer in the world and the most common among women. It is known that maternal and paternal food intake pattern are related to offspring susceptibility to non-communicable diseases, including cancer. Blackberry is one of the fruits with high antioxidant content and its compounds have antioxidant, anticarcinogenic and anti-inflammatory properties. So, the aim of the present study was evaluate the effects of maternal and/or paternal blackberry extract consumption on female offspring susceptibility to chemically-induced breast carcinogenesis. Thus, C57BL/6 mice were divided into 4 groups: father blackberry (FB), mother blackberry (MB), father and mother blackberry (FMB) and control (CTRL). Fathers received blackberry extract from weaning during 8 weeks and the mothers were treated during gestation and lactation. Blackberry extract was given in the drink water (0.84g anthocyanins/L) ad libitum. Fathers treated with blackberry had a reduction on superoxide dismutase (SOD) and catalase (CAT) activities in the testis (p<0.05 and p<0.001, respectivelly), an increase on plasmatic antioxidant capacity, percentage of normal sperm and daily sperm production in relation to control group (p<0.001 for all comparisons). Moreover, FB, MB and FMB groups had an increase of pregnancy rate (p<0.05) and a decrease of perinatal mortality (p<0.01, p<0.05 and p<0.001, respectively). Female offspring had a reduction of plasmatic antioxidant capacitity in FB (p<0.001) and MB (p<0.01) groups, while FMB group showed an increase in this parameter (p<0.001). On mammary gland development, it was observed higher epithelial development in FB, MB and FMB groups (p<0.001 for all comparisons), increased differentiation in MB and FMB groups (p<0.01 for both) and higher apoptosis rate in MB and FMB groups (p<0.05 for both), besides decreased TEBs number in FB, MB and FMB groups (p<0.01, p<0.001 and p<0.001, respectively). It was not found significant differences in the female offspring submitted to chemically-induced breast carcinogenesis. So, it is possible to conclude that in spite of maternal and/or paternal blackberry extract consumption changed the mammary gland development, it was not able to change the female offspring susceptibility to chemically-induced breast carcinogenesis.
36

Estabilidade de compostos bioativos em polpa congelada de amora-preta (Rubus fruticosus) cv.Tupy / Stability of bioactive compunds in frozen pulp of blackberry (Rubus fruticosus) cv. Tupy

Jacques, Andressa Carolina 31 July 2009 (has links)
Made available in DSpace on 2014-08-20T13:42:04Z (GMT). No. of bitstreams: 1 Dissertacao_Andressa_Carolina_Jacques.pdf: 729903 bytes, checksum: c29b8dc4bad8abf286333f2238a71dc8 (MD5) Previous issue date: 2009-07-31 / Brazil is considered one of the major consumer´s country of fruits, occupying the third worldwide position. The diversity of fruit for the market is growing, but their properties and activities are not fully determined. However, from the beginning of the 90s, a large fruit supply is justifying studies related to the development of new products, which in most cases concentrates the major consumption form as raw fruit or pulp. This work aimed to produce pulp from blackberry cv. Tupy, and store it under different temperature conditions (-10, -18 and -80 ºC) for 6 months, evaluating the stability of its main phytochemicals after processing and during the storage period. The results showed that the temperature of -10 °C was not sufficient to cause significant changes in relation to total phenols, total anthocyanins, antioxidant capacity and titrable acidity (2 months). The temperature of -18 ° C was not sufficient to cause significant changes in the pulp with respect to: total phenols and antioxidant capacity (4 months), total anthocyanins (2 months) and β-carotene (6 months). At temperature of -80 ° C, few changes were caused in the pulp stored for 6 months, and observed only small changes in soluble solids, hydroxybenzoic acid. Total and individual carotenoids in any of the three IPF temperatures sufficient to avoid losses. In Tocopherol, only in the pulp stored at -80 ° C for 2 months there was no change.The ascorbic acid was completely degraded within 6 months of storage at all temperatures (-10, -18 and -80 °C). The phenolics were the compounds that most contributed to the antioxidant capacity of blackberry cv. Tupy. / O Brasil é considerado um dos principais paises consumidores de frutas, ocupando a terceira posição mundial. A diversidade de frutas destinadas ao mercado é cada vez maior, mas suas propriedades e atividades não estão totalmente determinadas. No entanto, a partir do início da década de 90, a grande oferta de frutas vem justificando estudos direcionados ao desenvolvimento de novos produtos, que, na maioria das vezes, concentra na fruta in natura e na polpa suas maiores formas de consumo. Este trabalho teve por objetivo elaborar polpa de amora-preta da cultivar Tupy, e armazená-la sob diferentes condições de temperaturas (-10, -18 e -80 ºC) durante 6 meses, e avaliar a estabilidade de seus principais fitoquímicos após o processamento e durante o período de armazenamento. Os resultados demonstraram que a temperatura de -10°C foi suficiente para não causar alterações significativas com relação à fenóis totais, antocianinas totais, capacidade antioxidante e acidez titulável (2 meses). A temperatura de -18°C foi suficiente para não causar alterações significativas nas polpas com relação à: fenóis totais e capacidade antioxidante (4 meses), antocianinas totais (2 meses) e β-caroteno (6 meses). Na temperatura de -80°C, poucas foram as alterações causadas na polpa armazenada por 6 meses, sendo observado apenas pequenas alterações em sólidos solúveis, ácido hidroxibenzóico. Nos carotenóides totais e individuais nenhuma das três temperaturas fpi suficiente para evitar as perdas. Nos tocoferois, apenas na polpa armazenada a -80°C por 2 meses não houve alteração. E o ácido ascórbico foi totalmente degradado nos 6 meses de armazenamento nas duas temperaturas (-10 e -18°C). Os compostos que mais contribuíram para o poder antioxidante da amorapreta cv. Tupy foram os compostos fenólicos.
37

Porting an iOS Application to the Android OS Platform. : Garantikoll.se

Olsson, Björn January 2011 (has links)
Storing warranty receipts can sometimes be problematic. Receiptscan be lost, bleached and become illegible or in an extreme case, the storage area is destroyed. The company Freck AB offers a service to store these receiptsonline. They also provides a webpage where the user is able to handle their receipts and an iPhone client for easier uploading. Since the smartphones are increasing in market share each year, with different operating systems, it causes a market fragmentation. If Freck AB wants to address more potential customers, the application needs to get ported to more platforms. Currently iOS holds a 15.7% of the market share, and if the application is ported to the AndroidOS platform, 38.4% of the smartphone users will be addressed. This thesis will present a portation of an iOS application to the Android OS platform. It will also discuss basic Android programming together with the Android SDK classes and techniques used. The portation was considered successful and the subgoals were met. The application has been tested on multiple emulators and on one physical device with good results.
38

Hemijski sastav i biološki potencijal ploda, soka i tropa kultivisane i divlje kupine (Rubus fruticosus L.) / Chemical composition and biological potential of cultivated and wild blackberries (Rubus fruticosus L.)

Jazić Miodrag 09 December 2019 (has links)
<p>U okviru ove disertacije ispitan je hemijski, mineralni i<br />polifenolni sastav, kao i biolo&scaron;ki potencijal četiri sorte<br />kupina sa dva različita lokaliteta sjeverozapadnog dijela<br />Bosne i Hercegovine, sa lokaliteta Verići (divlja i<br />kultivisana sorta Čačanska bestrna) i sa lokaliteta<br />Javorani (divlja sorta i kultivisana sorta Chester<br />Thornles). Određen je sadržaj suve materije, pepela,<br />sirove celuloze, ukupnih &scaron;ećera, ukupna kiselost i sadržaj<br />askorbinske kiseline. Sadržaj mineralnih materija<br />detektovan je metodom optičke emisione spektrometrije<br />(ICP-OES). Za izdvajanje ekstrakata je kori&scaron;tena klasična<br />ekstrakciona tehnika prema Soxhlet-u uz upotrebu 80 %<br />etanola (v/v). Spektrofotometrijskim metodama određen<br />je sadržaj ukupnih polifenola, flavonida, flavonola,<br />ukupnih i monomernih antocijana. Kvalitativnom i<br />kvantitativnom HPLC metodom je utvrđen sadržaj<br />pojedinačnih polifenolih jedinjenja. Biolo&scaron;ki potencijal<br />uzoraka je utvrđen u sistemima in vitro, gdje je određena:<br />antioksidativna aktivnost, antihiperglikemijska aktivnost,<br />antiproliferativni efekat i antimikrobna aktivnost.<br />Antioksidativna aktivnost uzoraka je ispitana sa četiri<br />metode: DPPH test, ABTS test, sposobnost neutralizacije<br />hidroksil radikala i metodom inhibicije Briggs Rauscherovih oscilatornih reakcija. Antihiperglikemijska aktivnost<br />ispitivanih uzoraka kupine je dokazan na osnovu<br />sposobnosti inhibicije enzima &alpha;-glukozidaze.<br />Antiproliferativni efekat ispitivanih uzoraka je određen<br />prema inhibiciji rasta četiri humane ćelijske linije: HeLa<br />(epitelnog karcinoma cerviksa), HT-29 (adenokarcinoma<br />debelog crijeva), MRC-5 (zdravim ćelijama fibroblasti<br />pluća) i prema ćelijskoj liniji MCF7 (adenokarcinoma<br />dojke). Antimikrobna aktivnost je utvrđena prema gram<br />pozitivnom soju (G<sup>+</sup>) bakterija S. Aureus i gram<br />negativnom (G<sup>-</sup>) soju E. coli, rastu micelija Aspergillusa<br />niger i Candida albicans. Regresionom analizom prema<br />Pirson-u su određeni odnosi između sadržaja polifenolnih<br />jedinjenja i biolo&scaron;kog potencijala, sa statističkim<br />značajem (p &le; 0,01).</p> / <p>The chemical, mineral, polyphenolics composition and<br />biological potentials of four blackberries varieties from two<br />different locations in the northwestern part of Bosnia and<br />Herzegovina (Verići - wild and cultivated variety Čačanska<br />bestrna and Javorani - wild and cultivated variety Chester<br />Thornless) were determined. The contents of dry matter, ash,<br />crude cellulose, total sugars, total acidity and ascorbic acid were<br />obtained. The contents of mineral matter were detected by<br />optical emission spectrometry (ICP-OES) method. A classic<br />Soxhlet extraction technique with 80% ethanol (v/v) was<br />applied to obtain extracts. The spectrophotometric methods<br />were used to determine the content of total polyphenolics,<br />flavonoids, flavonols, and total and monomer anthocyanins. The<br />content of individual polyphenolic compounds was determined<br />by HPLC method. The biological potentials (antioxidant<br />activity, antihyperglycemic activity, antiproliferative effect and<br />antimicrobial activity) of the samples were determined in vitro<br />systems. The antioxidant activity was tested with four methods:<br />DPPH test, ABTS test, ability to neutralize OH radicals and the<br />method of inhibiting Briggs Rauscher oscillatory reactions. The<br />antihyperglycaemic activity of the tested blackberry samples<br />was based on the ability to inhibit &alpha;-glucosidase enzyme. The<br />antiproliferative effect of the tested samples was determined by<br />inhibiting the growth of four human cell lines: epithelial<br />carcinoma of the cervix (HeLa), colon adenocarcinoma (HT-<br />29), healthy lung fibroblast cells (MRC-5) and the cell line of<br />breast adenocarcinoma (MCF7). The extracts showed the<br />highest inhibitory effect on the cell line of breast<br />adenocarcinoma (MCF-7). The antimicrobial activity was<br />determined according to gram-positive bacteria (G <sup>+</sup>) of<br />Staphylococcus aureus, Gram-negative bacteria (G <sup>-</sup>)<br />Escherichia coli, growth of mycelium Aspergillus niger and<br />fungi Candida albicans. The Pearson correlations were<br />statistically determined the relationship between the content of<br />polyphenolic compounds and biological potential, with<br />statistical significance (p &le; 0.01).</p>
39

Study of the health promoting properties of the tropical highland blackberry (Rubus adenotrichos) and the impact of digestion and pasteurization processes / Étude des propriétés bénéfiques pour la santé de la mûre tropicale de montagne (Rubus adenotrichos) et détermination de l'impact des processus de digestion et de pasteurisation.

Azofeifa, Gabriela 16 December 2013 (has links)
Dans cette étude nous avons évalué les activités biologiques de la mûre tropicale de montagne (Rubus adenotrichos) et les effets de la digestion ou des procédés de pasteurisation sur ces activités. L'extrait polyphénolique de mûre présente un pouvoir antioxydant déterminé par la méthode ORAC de 4339 ± 144 pM TE/g, plus élevé que celui de la quercétine et de l'acide ellagique. L'extrait de mûre présente des propriétés protectrices des liposomes et des homogénats de foie contre la peroxydation lipidique avec des IC50 de 7.0 ± 0.5 et 20.3 ± 4.2 mg/ml, respectivement. Les polyphénols de mûre inhibent la production de nitrite dans par les macrophages murins J774A.1 stimulées par le mélange LPS, IFN. Cette activité est confirmée par la diminution du taux de NO synthase inductible dans ces mêmes cellules. Les activités biologiques des fruits pourraient être affectés par les procédés industriels. Le processus de pasteurisation du jus de mûre a provoqué une diminution d'environ 7% de la concentration en anthocyanes pour la température la plus élevée évalué, 92°C. Pour le même échantillon, une réduction significative de 27% de l'activité anti-oxydante mesurée par la méthode DPPH et de 16% de la capacité de complexassions des radicaux NO. Toutefois, aucune différence significative n'a été mise en évidence autant pour la capacité d'inhibition de la peroxydation que pour l'activité anti-oxydante intracellulaire. Les effets in vivo sont largement dépendants de la biodisponibilité des composés phénoliques et de ce fait un jus de mûre a été digéré in vitro pour obtenir des échantillons qui représentent les grandes étapes du processus de digestion. La digestion gastrique a peu d'influence au contraire de la digestion intestinale sur la composition polyphénolique de l'extrait de mûre en particulier au niveau du rapport anthocyanines/elagitannins. La fraction dialysable présente une réduction de 33% et de 35% de l'activité contre les radicaux dérivés de l'azote DPPH et NO, respectivement. De même, la capacité d'inhiber au niveau intracellulaire les radicaux libres (ROS) a diminué d'environ 85%. Toutefois, aucune différence significative n'a été mise en évidence au niveau de la capacité d'inhiber la peroxydation lipidique. Finalement, cette étude a utilisé un modèle in vivo pour évaluer l'effet de la consommation d'une boisson de mûre chez des rats diabétiques. L'apport de mûre a provoqué une diminution du glucose (-48.6%), des triglycérides (-43.5%) et du taux de cholestérol (-28.6%) plasmatique des rats diabétiques par rapport aux témoins diabétiques qui n'ont pas consommé la boisson de ce fruit. De plus, les rats diabétiques qui consomment de la mûre ont vus améliorées les valeurs de la capacité antioxydante du plasma (+7%), tandis que les niveaux de peroxydation lipidique dans le plasma (-19%) et dans les tissus rénaux (-23%) ont été réduits. Cette étude suggère que l'incorporation de la mûre comme un complément alimentaire pourrait avoir des effets bénéfiques sur la santé, même si l'on considère les aspects de biodisponibilité et les effets du procédé de pasteurisation. / This study evaluated biological activities of blackberries (Rubus adenotrichos) and the effects of digestion or pasteurization processes on these activities. The blackberries phenolic extract showed an ORAC value of 4339 ± 144 μM TE/g, higher than those of quercetin and ellagic acid. It also protected liposomes and liver homogenates against lipid peroxidation; with IC50 of 7.0 ± 0.5 and 20.3 ± 4.2 μg/mL, respectively. The blackberry polyphenols inhibited nitrite production in J774A.1 cells stimulated with LPS+IFNγ due to down-regulation of iNOS protein expression, suggesting an anti-inflammatory potential. The biological activities of the fruits could be affected by the industrial processes. The pasteurization of a blackberry juice caused a 7% decrease in the anthocyanins concentration of the highest temperature tested, 92 °C. For the same sample, a significant reduction of 27% and 15% were showed in the DPPH and NO scavenging capacity, respectively. However, non-significant differences were evident neither for the peroxidation inhibitory capacity nor for the intracellular antioxidant activity after the pasteurization step. The antioxidant capacity is largely dependent of their bioavailability and because of this a blackberry juice was digested in vitro to obtain samples that represent the major stages of the digestion process. The gastric digestion had slight impact on polyphenolic composition while the pancreatin/bile digestion had marked effects on polyphenolic composition, particularly in the ratio anthocyanins-ellagitannins. These changes in phenolic composition caused in the dialyzed fraction a reduction of 33% and 35% in the activity against nitrogen derived radicals DPPH and NO respectively. As well the capacity to inhibit intracellular ROS was decrease by an 85% in the dialyzed fraction. Nevertheless, no significant differences were evident in the capacity to inhibit lipid peroxidation. Finally, this study used an in vivo model with diabetic rats to evaluate the effect of the consumption of a blackberry beverage. The blackberry intake provoked a decrease in plasmatic glucose (-48.6%), triglycerides (-43.5%) and cholesterol (-28.6%) levels in the diabetic rats with respect to the diabetic controls animals. The diabetic rats which consumed blackberry, improved (+7%) the plasma antioxidant capacity (PAC) values and reduced the levels of lipid peroxidation in plasma (-19%) and in kidney tissue (-23%). This study suggests that selecting blackberry as a dietary complement could have health beneficial effects even when considering the bioavailability aspects of the phenolic compounds and the pasteurization effects.
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Impact des opérations thermiques agroalimentaires à hautes températures sur la dégradation des anthocyanes : caractérisation et modélisation des cinétiques réactionnelles / Impact of food thermal operations at high temperature on the degradation of anthocyanins : characterization and modeling of reaction kinetics

Jimenez Elizondo, Nadiarid 13 December 2011 (has links)
Compte tenu de l'importance des pigments naturels dans les aliments et leur sensibilité aux traitements thermiques, les cinétiques de dégradation des anthocyanes ont été étudiées à très hautes températures (100 à 180 ºC). Pour obtenir une base de données expérimentale fiable dissociant les transferts d'énergie et de matière, un mini-réacteur étanche a été utilisé pour le traitement d'une matrice modèle (jus de mûre et sable) en faisant varier la température et l'activité de l'eau (0,20<aw<0,99). L'hypothèse d'une réaction d'ordre 1 pour la dégradation des anthocyanes a permis de modéliser et de déterminer les paramètres cinétiques suivant une méthode non-isotherme prenant en compte à la fois le profil de température et indépendamment l'homogénéité ou l'hétérogénéité du champs de température au sein de la matrice. Il a été démontré que les constantes de réaction sont très influencées par la diminution de l'activité de l'eau, facteur qui fait augmenter la réactivité. Ces résultats originaux ont été validés sur une matrice alimentaire (papaye verte-jus de mûre) soumise au couplage d'un procédé de formulation par déshydratation par immersion-imprégnation, suivi d'une opération de friture, à l'aide d'un modèle qui intègre les transferts de vapeur et d'énergie et la cinétique réactionnelle. Le modèle permet une meilleure compréhension des phénomènes et il peut être intégré dans une démarche d'optimisation séquentielle associant différentes opérations unitaires avec des traitements thermiques à très hautes températures. / Given the importance of natural pigments in foods and their sensitivity to heat treatment, degradation kinetics of anthocyanins have been studied at very high temperatures (100 to 180 ºC). For a reliable experimental database that dissociates heat and mass transfer, a hermetic mini-reactor was used for the treatment of a model matrix (blackberry juice and sand) by varying the temperature and activity water (0.20<aw<0.99). The assumption of a first order reaction for the anthocyanins degradation was used to model and determine the kinetic parameters using a non-isothermal method taking into account both the temperature profile and independently the homogeneity or heterogeneity of the matrix temperature field. It has been shown that the rate constants are strongly influenced by the water activity reduction, a factor that increases the anthocyanins reactivity. These original results were validated on a food matrix (green papaya-blackberry juice) submitted to the coupling of a formulation process by osmotic dehydration, followed by a deep-fat frying operation, using a model which includes the vapor and heat transfer and the reaction kinetics. The model allows a better understanding of the phenomena and can be integrated into a sequential optimization approach combining different unit operations with heat treatments at high temperatures.

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