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Contamina??o f?ngica tox?gena e qualidade micotoxicol?gica de silagens destinadas a alimenta??o de bovinos no Estado de S?o Paulo / Mycological and Mycotoxicology evaluation of silage intended to a food on cattle Farms in the state of Sao PauloKELLER, Luiz Antonio Moura 18 March 2013 (has links)
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Previous issue date: 2013-03-18 / CNPq / Despite having the second largest cattle herd in the world. The Brazilian has low rates of productivity. The performance of the animals in pastures is reasonable during the rainy season, being in the dry food deficiency, caused by the low availability and quality of grass, which results in weight loss of animals. Thus ensiled foods are a recently solution to this situation in the production process. But we have a very few studies on the food substrate in Brazil and Latin America. The objectives of this study were primarily to establish the natural frequency of species of the genera Aspergillus, Penicillium and Fusarium potentially produce mycotoxins in samples of vegetable and silage components intended for cattle and other fungal genera present and detect mycotoxins presents in the same (aflatoxins, ochratoxin A, fumonisin B1, deoxinivalenol and glyotoxin). We are evaluated a total of 168 samples of corn and sorgum silos, from Janerie 2009 to October 2012. These farms creators of beef cattle were located in the state of S?o Paulo. We evaluated the pre and post fermented samples during this period. In all substrates had evaluated more than 50% of samples contaminated above the recommended limits feed of 1.0 x 104 ufc.g-1 (GMP, 2006). As in other studies the genera Aspergillus and Penicillium have high occurrence following related studies in the Americas and worldwide. Aspergillus flavus was the species of greatest occurrence in the samples evaluated, followed by A. niger aggregate, A. fumigatus and A. parasiticus. Presence was detected in high levels of toxins produced by these genera mainly: aflatoxins (up to 70 ppb) glyotoxin (up to 30 ppm) and ochratoxin A (up to 10 ppm). The Fusarium sp. showed a low variability of species in the samples evaluated, even in pre-fermented samples where counts were higher in this genera, had the occurrence of only two species F. verticillioides and F. gramineraum. Next to it was also the detection of toxins produced by these genera at low levels (levels of 0.32-2 ppm).T hese observations creates the need to expand studies related to ensiled food, which the animals were feed during major periods of the year. / Apesar de ter o segundo maior rebanho do mundo a bovinocultura de corte brasileira, apresenta modestos ?ndices de produtividade. O desempenho dos animais em pastagens ? razo?vel durante a esta??o chuvosa, observando-se na esta??o seca defici?ncia alimentar, causada pela baixa disponibilidade e qualidade do pasto, o que resulta em perda de peso dos animais. Assim, alimentos ensilados s?o uma solu??o atualmente utilizada a esta situa??o no processo produtivo. A avalia??o deste substrato alimentar ? escassa tanto no Brasil quanto no restante da Am?rica Latina, assim, os objetivos deste trabalho foram os de estabelecer principalmente a freq??ncia natural de esp?cies dos g?neros Aspergillus, Penicillium e Fusariu potencialmente produtoras de micotoxinas em amostras de componentes vegetais e silagens destinadas ao consumo bovino, bem como de outros g?neros f?ngicos presentes e detectar micotoxinas presentes nas mesmas (aflatoxinas, ocratoxina A, fumonisina B1, deoxinivalenol e gliotoxina). Foram avaliados um total de 168 amostras de ensilados de milho e sorgo no per?odo de janeiro 2009 a outubro 2012 (avaliado o material pr? e p?sfermentado nesse per?odo), provenientes de tr?s fazendas criadoras de gado de corte no estado de S?o Paulo. Foi observado que em todos os substratos avaliados tiveram mais de 50% de amostras contaminadas acima dos limites recomendados para alimenta??o animal de 1,0 x 104 ufc.g-1 (GMP, 2006). Sendo Aspergillus flavus ? esp?cie de maior ocorr?ncia nas amostras avaliadas, seguida por A. niger agregado, A. fumigatus e A. parasiticus. Detectou-se presen?a em n?veis altos de toxinas produzidas por esses g?neros principalmente: aflatoxinas (n?veis acima de 70 ppb), gliotoxina (n?veis acima de 30 ppm) e ocratoxina A (n?veis de at? 10 ppm). O g?nero Fusarium apresentou uma variabilidade baixa de esp?cies nas amostras avaliadas, mesmo em amostras pr?-fermentadas onde ocorreram contagens maiores deste g?nero, tiveram a ocorr?ncia de apenas duas esp?cies F. verticillioides e F. gramineraum. Junto a isso tamb?m tiveram a detec??o de toxinas produzidas por esses g?neros em n?veis baixos (n?veis de 0,32-2 ppm), principalmente no milho pr?-fermentado. Tais achados refor?am a avalia??o mais ampla desse substrato que ? base alimentar durante grandes per?odos do ano para o nosso rebanho.
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QUALIDADE FÍSICO-QUÍMICA E MICROBIOLÓGICA DE GRÃOS DE MILHO NO ARMAZENAMENTO INFESTADOS COM Sitophilus zeamais / PHYSICO-CHEMICAL AND MICROBIOLOGICAL QUALITY OF CORN KERNELS IN STORAGE INFESTED WITH Sitophilus zeamaisPaloschi, Cristiane Lurdes 15 July 2014 (has links)
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Previous issue date: 2014-07-15 / Fundação Araucária / This work aimed to study the effects of infestation of insects Sitophilus zeamais on the physicochemical and microbiological quality in corn kernels during storage. For the experiment, samples of hybrid maize (Zeamays) were collected from cultivar Dow 2B512Hx, grown in western Paraná, harvested in June / July 2013. For storage, the grains had water contents below 15% bs, and about 300g of them were stored in glass containers closed with tissue type Voil to facilitate gas exchange, with a total of 40 containers stored in a BOD incubator at a temperature of 27±1 °C for 180 days. From all the recipients, 20 were infested with 20 adult insects of Sitophilus zeamais and the other 20 were kept uninfested. Every 45 days, samples were taken and physical and chemical analyzes were carried out (grain weight loss, population variation of insects, classification of corn, mass of 1000 seeds, water content, ash, oil, protein and carbohydrates and dietary fiber total), as well microbiological analyzes (counting of filamentous fungi and identification of aflatoxin-producing fungi) and quantitation of aflatoxin (B1, B2, G1 and G2). Exploratory analysis of the response variables was done by use of the analysis of variance (ANOVA) and mean comparison test was performed by Tukey's test with a significance level of 0.05. The final grain weight in dry material with insects reduced in the course of time, what increased the losses in grain mass and showed statistically significant differences. The population of insects and the classification of maize also showed statistically significant differences. It was observed that when storage time increased, the population of insects also increased and the percentage of whole grains reduced for both storage conditions. The content of water, protein and filamentous fungi incidence increased in grains initially infested during storage, and the 1000 grains weight, the content of carbohydrates and total dietary fiber content in these grains decreased compared to uninfected grains. The incidence of aflatoxin was not detected in maize kernels during the studied storage period. Finally, from these results, it is possible to conclude that the longer the period of contact of insects with the largest grains, larger the damages and losses to producers are. However, S. zeamais did not behave as a mechanical vector of the fungus Aspergillus ssp., with no correlation between the incidence of filamentous fungi and the level of aflatoxins (B1, B2, G1 and G2). / Este trabalho teve como objetivo estudar os efeitos da infestação dos insetos Sitophilus zeamais sobre a qualidade físico-química e microbiológica em grãos de milho durante o armazenamento. Para a condução do experimento, foram coletadas amostras de grãos de milho (Zeamays) híbrido da cultivar Dow 2B512Hx, cultivados na região Oeste do Paraná, colhidas em junho/julho de 2013. Para o armazenamento, os grãos se encontravam com teores de água abaixo de 15% b.s sendo armazenados cerca de 300 g em recipientes de vidros fechados com tecido tipo Voil, a fim de facilitar as trocas gasosas, totalizando 40 recipientes armazenados em câmera incubadora B.O.D à temperatura de 27±1 °C durante 180 dias. Do total de recipientes, 20 foram infestados com 20 insetos adultos de Sitophilus zeamais e os outros 20 foram mantidos sem infestação. A cada 45 dias, foram retiradas as amostras e realizadas análises físico-químicas (perda de massa dos grãos, variação populacional dos insetos, classificação do milho, massa de 1000 grãos, teor de água, cinzas, óleo, proteína e carboidratos e fibra alimentar total), microbiológicas (contagem de fungos filamentosos e identificação dos fungos produtores de aflatoxinas) e de quantificação de aflatoxinas (B1, B2, G1 e G2). A análise exploratória das variáveis respostas foi analisada pelo emprego da análise de variância (ANOVA) e o teste de comparação de médias foi realizado pelo teste de Tukey com nível de significância de 0,05. O peso final dos grãos em matéria seca com insetos reduziu ao longo do tempo, aumentando as perdas na massa dos grãos, apresentando diferenças estatísticas significativas. A população de insetos e a classificação do milho também apresentaram diferenças estatísticas significativas. Observou-se que, conforme aumentava o tempo de armazenamento, aumentava a população de insetos e reduzia a percentagem de grãos inteiros para ambas as condições de armazenamento. O teor de água, proteína e a incidência de fungos filamentosos aumentaram nos grãos inicialmente infestados ao longo do armazenamento e o peso de 1000 grãos e o teor de carboidratos e fibra alimentar total dos grãos diminuiu nestes grãos em relação aos grãos que não infestados. A incidência de aflatoxinas não foi detectada nos grãos de milho durante o período de armazenamento analisado. Pode-se concluir, com base nesses resultados, que quanto maior o período de contato dos insetos com os grãos maiores são os danos causados e os prejuízos para os produtores, porém o S. zeamais não se comportou como um vetor mecânico do fungo Aspergillus ssp., não havendo correlação entre a incidência de fungos filamentosos e o nível de aflatoxinas (B1, B2, G1 e G2).
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Infestação de sitophilus zeamais na qualidade físico-química e microbiológica de grãos de trigo armazenados / Sitophilus zeamais infestation in the physical-chemical and microbiological quality of stored grains of wheatPintro, Tania Claudia 12 February 2015 (has links)
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Previous issue date: 2015-02-12 / The objective of this study was to evaluate the effect of insect infestation Sitophilus zeamais on the physicochemical and microbiological quality in wheat grains, during storage in times of 0, 45, 90 and 135 days, in three temperatures: 20, 25 and 30 ºC. For the conduct of the experiment, wheat grain samples were collected (Triticum aestivum L.) of the cultivar BRS Tanager, produced in Western Paraná, from the harvest of 2013. For storage, the grains had water contents below 13%, being stored about 400 g in sealed glass containers with fabric type voil in order to facilitate gas exchange, totaling 72 containers stored in incubator BOD the temperature of 20, 25 and 30 ° C for 135 days. Of the total of containers, 36 were infested with 20 adults of Sitophilus zeamais and the other 36 were kept without infestation. Every 45 days, were samples for subsequent chemical-physical analysis (moisture, ash, and total protein population variation of insects), microbiological (filamentous fungi count and identification of fungi producing of deoxynivalenol) and quantifying of deoxynivalenol for the three temperatures at baseline and 135 days with and without infestation. The samples were evaluated by the use of analysis of variance (ANOVA) and for test of comparison of means the Tukey test was applied, with 5% level of significance. It was observed that, with increased storage time, increased population of insects, mainly at temperatures of 20 and 25° C, reducing the value of the weight of the hectolitre at both temperatures. In general, the water content was reduced with increasing temperature and time of the storage. The contents of protein, in the treatments with and without infestation, increased with storage time. In general, the ash content increased with time of storage in grain, with and without infestation in the three temperatures evaluated. The total count of CFU of filamentous fungi was greater for grains of wheat infested. The results obtained indicate that all samples of grain stored, analyzed in the initial time and 135 days, with and without infestation, for use at temperatures of 20, 25 and 30 ᵒC, are within the maximum tolerable limit of 3000 μg of deoxynivalenol per kg of wheat. / O objetivo deste trabalho foi avaliar o efeito da infestação de insetos Sitophilus zeamais sobre a qualidade físico-química e microbiológica de grãos de trigo, durante o armazenamento nos tempos de 0, 45, 90 e 135 dias e em três, temperaturas: 20, 25 e 30 ºC. Para a condução do experimento, foram coletadas amostras de grãos de trigo (Triticum aestivum L.) do cultivar BRS Tangará, produzido na região Oeste do Paraná e provenientes da safra de 2013. Para o armazenamento, os grãos apresentaram teores de água abaixo de 13%, sendo armazenados cerca de 400 g em recipientes de vidros, fechados com tecido tipo voil a fim de facilitar as trocas gasosas, totalizando 72 recipientes armazenados em câmara incubadora B.O.D. nas temperaturas de 20, 25 e 30 °C, no tempo de 135 dias. Do total de recipientes, 36 foram infestados com 20 insetos adultos de Sitophilus zeamais e os outros 36 foram mantidos sem infestação. A cada 45 dias, foram retiradas amostras, para posterior análise físico-química, (teor de água, cinzas, proteína total e variação populacional de insetos), microbiológicas (contagem de fungos filamentosos e identificação dos fungos produtores de desoxinivalenol) e de quantificação de desoxinivalenol, para as três temperaturas no tempo inicial e de 135 dias com e sem infestação. As amostras foram avaliadas pelo emprego da análise de variância (ANOVA) e para o teste de comparação de médias foi aplicado o teste de Tukey, com nível de 5% de significância. Observou-se que conforme aumentava o tempo de armazenamento aumentava também a população de insetos, principalmente para as temperaturas de 20 e 25 °C, reduzindo o valor do peso hectolitro em ambas as temperaturas. Em geral, o teor de água diminuiu quando ocorreu aumento de temperatura e tempo de armazenamento. Os teores de proteínas, nos tratamentos com e sem infestação, aumentaram com o tempo de armazenamento. Em geral, o teor de cinzas aumentou com o tempo de armazenamento nos grãos com e sem infestação, nas três temperaturas avaliadas. A contagem total de UFC de fungos filamentosos foi maior para grãos de trigo infestados. Os resultados obtidos mostram que todas as amostras de grãos armazenados, analisadas no tempo inicial e de 135 dias, com e sem infestação para as temperaturas de 20 25 e 30 ᵒC, estão dentro do limite máximo tolerável de 3000 μg de desoxinivalenol por kg de trigo
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Uticaj ekstrakata žačina na rast plesni i biosintezu mikotoksina / The effect of spice extracts on the growth of moulds and mycotoxinbiosynthesisKocić-Tanackov Sunčica 18 July 2012 (has links)
<p>Cilj istraživanja doktorske disertacije bio je da se ispita pojedinačni i sinergistički uticaj<br />ekstrakata kima (Carum carvi L.), bosiljka (Ocimum basilicum L.), origana (Origanum<br />vulgare L.) i etarskih ulja crnog (Allium cepa L. kultivar Kupusinski jabučar) i belog luka<br />(Allium sativum L. kultivar Bosut) na rast plesni izolovanih iz prehrambenih proizvoda, kao i<br />njihov uticaj na biosintezu mikotoksina.<br />Ukupan broj plesni u uzorcima salata od povrća spremnih za konzumiranje kretao se od<br />10,0 do 5,5´102 cfu/g, u uzorcima poslastičarskih proizvoda do 6,1´102 cfu/g i u<br />proizvodima od mesa do 60,0 cfu/g. Najveći broj plesni izolovan je na DG18 podlozi<br />(1,53´102 cfu/g), a najmanji na MY50G (42,0 cfu/g). U ukupnoj mikopopulaciji svih ispitivanih<br />uzoraka dominirale su vrste rodova Penicillium (39,07%), Cladosporium (23,40%) i<br />Aspergillus (20,42%). Vrste iz rodova Alternaria, Fusarium i Eurotium su bile zastupljene sa<br />5,85%, 4,97% i 2,76%. Dominantne vrste u ukupnoj mikopopulaciji bile su C.<br />cladosporioides (21,63%), A. niger (16,0%) i P. aurantiogriseum (11,81%).<br />Dominirali su potencijalni producenti ohratoksina A (31,89%), proizvoñači fumonizina<br />(4,74%), moniliformina (1,43%) i sterigmatocistina (1,54%). Izolati A. versicolor su<br />biosintetisali sterigmatocistin u koncentracijama od 56,3 i 109,2 ng/mL. Ostale potencijalne<br />toksin-produkujuće vrste nisu pokazale sposobnost produkcije mikotoksina.</p><p>Mikotoksikološkim ispitivanjem hrane u dva uzorka salata spremnih za konzumiranje<br />(kupus beli rezani i FIT salata) utvrñen je sadržaj sterigmatocistina u koncentracijama od 3,5<br />i 5,5 mg/kg.<br />Kao glavna komponenta u ekstraktu kima odreñen je karvon (43,98%), u ekstraktu bosiljka<br />estragol (metil kavikol) (86,72%), a u ekstraktu origana karvakrol (34,20%) i karvon (18,05%).<br />Najveći deo etarskog ulja crnog luka činili su: dimetil-trisulfid, metil-propil-trisulfid, dimetiltetrasulfid,<br />dietil-1,2,4-tritiolan, metil-(1-propenil)-trisulfid, metil-(1-propenil)-disulfid. Dialildisulfid,<br />dialil-trisulfid, metil-alil-trisulfid i metil-alil-disulfid su glavne komponente koje su<br />odreñene u etarskom ulju belog luka.<br />Koncentracija od 0,35 mL/100 mL ekstrakta kima je bila fungicidna (MFC) prema C.<br />cladosporioides, dok je 0,70 mL/100 mL potpuno inhibirala rast A. carbonarius, A. wentii, E.<br />nidulans, Eurotium spp., C. cladosporioides, P. glabrum, P. brevicompactum, F.<br />subglutinans i F. verticillioides. Na rast P. chrysogenum i P. aurantiogriseum ista<br />koncentracija bila je inhibitorna (MIC). Najslabije delovanje ovaj ekstrakt ispoljio prema A.<br />niger, A. versicolor, F. oxysporum i F. proliferatum.<br />Primena ekstrakta bosiljka u koncentraciji od 0,70 mL/100 mL pokazala je fungicidno<br />delovanje na C. cladosporioides. Koncentracija od 1,50 mL/100 mL potpuno je inhibirala<br />rast A. wentii, A. versicolor, E. nidulans, E. herbariorum, E. chevalieri, E. rubrum, P.<br />chrysogenum i Fusarim spp. Ekstrakt bosiljka je najslabije delovao prema A. niger, A.<br />carbonarius, P. aurantiogriseum, E. amstelodami, P. glabrum i P. brevicompactum.<br />Ekstrakt origana je pokazao najslabije ihibitorno delovanje na rast ispitivanih plesni.<br />Primena ekstrakta u koncentraciji od 1,50 mL/100 mL je bila fungicidna prema E. rubrum.<br />Koncentracija od 2,50 mL/100 mL je pokazala fungicidno delovanje na E. rubrum, E.<br />herbariorum, A. wentii, C. cladosporioides i P. aurantiogriseum, a inhibitorno prema E.<br />nidulans, E. chevalieri, E. amstelodami, P. glabrum i P. brevicompactum. Ovaj ekstrakt je<br />najslabije delovao na A. niger, A. carbonarius, F. proliferatum, F. subglutinans i P.<br />chrysogenum.<br />Etarsko ulje crnog luka pokazalo je signifikantno jače antifungalno delovanje na ispitivane<br />plesni u odnosu na etarsko ulje belog luka. Koncentracija od 14,0 mL/100 mL ulja belog luka<br />fungicidno je delovala prema E. rubrum, E. chevalieri i C. cladosporioides, dok je ulje crnog<br />luka na ovoj koncentraciji pokazalo fungicidni efekat i na E. herbariorum i E. amstelodami.<br />Za ostale plesni fungicidna koncentracija iznosila je 28,0 mL/100 mL, osim za A. niger i P.<br />aurantiogriseum.<br />Neke od ispitivanih smeša bosiljka i kima, bosiljka i origana, origana i kima i etarskih ulja<br />lukova pokazale su sinergističko delovanje na inhibiciju rasta A. wentii, E. herbariorum, F.<br />verticilllioides i P. aurantiogriseum sa FICindex od 0,63 do 0,97.<br />Začinski ekstrakti i etarska ulja lukova su pored ograničavanja rasta kolonija plesni<br />uzrokovali i promene u makro i mikromorfologiji.<br />Potpuna inhibicija biosinteze sterigmatocistina i rasta A. versicolor postignuta je pri<br />koncentraciji od 0,20 mL/100 mL ekstrakta kima i origana u periodu od 21 dana. Na ovoj<br />koncentraciji ekstrakt bosiljka je inhibirao biosintezu sterigmatocistina za 88,73% i rast<br />plesni za 52,56%. Smeša koja je sadržavala 75% ekstrakta kima i 25% ekstrakta bosiljka<br />potpuno je inhibirala rast plesni i biosintezu sterigmatocistina u YES bujonu tokom 21 dana<br />inkubiranja.<br />Pojedinačne koncentracije etarskih ulja crnog i belog luka od 5,0 i 10,0 mL/100 mL i u smeši<br />sa 1,50 mL/100 mL etarskog ulja crnog luka i 0,50 mL/100 mL etarskog ulja belog luka bile su<br />potrebne za potpunu inhibiciju rasta A. versicolor i biosintezu sterigmatocistina.<br />Dodatak smeše ekstrakata kima i bosiljka (0,35 mL/100 mL ekstrakta kima + 0,70 mL/100 mL<br />ekstrakta bosiljka) u svež kupus rezanac uticao je na smanjenje inicijalne kontaminacije<br />plesnima za 93,9%, uz pojavu intenzivnijeg, ali prihvatljivog mirisa i neznatne promene boje.</p><p>Definisani matematički model za komparaciju uticaja ekstrakata i etarskih ulja na rast plesni<br />može se primenjivati u formiranju matrica inhibicije i optimizaciji vremena i koncentracije<br />antifungalnih agenasa.<br />Dobijena saznanja o antifungalnom delovanju ekstrakata začina i etarskih ulja lukova mogu<br />biti značajna u poboljšanju antifungalne zaštite namirnica, smanjenju biosinteze<br />mikotoksina i ukupnim smanjenju šteta izazvanih delovanjem plesni.</p> / <p>The aim of this PhD thesis was to study the individual and synergistic effects of extracts of<br />caraway (Carum carvi L.), basil (Ocimum basilicum L.), oregano (Origanum vulgare L.) and the<br />essential oils of onion (Allium cepa L. cultivar Kupusinski jabučar) and garlic (Allium sativum<br />L. cultivar Bosut) on the growth of moulds isolated from food products. The study also<br />focused on the impact of extracts and the essential oils on mycotoxins biosynthesis.<br />The total number of moulds detected in samples of vegetable salads “ready for use” ranged<br />from 10.0 to 5.5´102 cfu/g. In cake and pastries, as well as, meat samples, the number<br />reached 6.1´102 cfu/g and 60.0 cfu/g, respectively. The highest number of mould colonies was<br />isolated in DG18 medium (1.53 ´ 102cfu/g) and the lowest in MY50G medium (42.0 cfu/g). The<br />species of the genera Penicillium (39.07%), Cladosporium (23.40%) and Aspergillus (20.42%)<br />prevailed in the entire mycopopulation of all tested samples. Species of the genera Alternaria,<br />Fusarium and Eurotium were represented with 5.85%, 4.97% and 2.76%, respectively, while C.<br />cladosporioides (21.63%), A. niger (16.0%) and P. aurantiogriseum (11.81%) were the most<br />dominant species in the entire mycopopulation.<br />Potential producers of ochratoxin A (31.89%) accounted for the largest share of the isolated<br />mycopopulation. The share of producers of fumonisin, moniliformin and sterigmatocystin<br />amounted to 4.74%, 1.43% and 1.54%, respectively. Sterigmatocystin was biosynthesised in</p><p>the concentration of 56.3 ng/mL and 109.2 ng/mL by both isolates of A. versicolor, while other<br />potential toxin producers did not show the ability of mycotoxin production.<br />Mycotoxicological investigation showed the sterigmatocystin content in two samples of<br />vegetable salads "ready for use" (shredded white cabbage and FIT salad - carrot, lettuce and<br />red chicory) in concentrations of 3.5 mg/kg and 5.5 mg/kg, respectively.<br />The major component in the extract of caraway was carvon with a share of 43.98%. The basil<br />extract contained estragol (methyl cavicol) in the highest percentage (86.72%), while<br />carvacrol (34.20%) and carvon (18.05%) were major components of the oregano extract. As for<br />the essential oil of onion, dimethyl trisulphide, methyl propyl trisulphide, dimethyl tetrasulfid,<br />diethyl-1, 2, 4-tritiolan, methyl-(1-propenyl)-trisulphide, and methyl-(1-propenyl) – disulfide<br />constituted the largest share. The major components isolated in garlic essential oil were<br />diallyl disulfide, diallyl-trisulphide, allyl methyl trisulphide and allyl methyl disulfide.<br />The concentration of the caraway extract of 0.35 mL/100mL exhibited fungicidal effect (MFC)<br />on C. cladosporioides, while the concentration of 0.70 mL/100mL completely inhibited the<br />growth of A. carbonarius, A. wentii, E. nidulans, Eurotium spp., C. cladosporioides, P.<br />glabrum, P. brevicopmactum, F. subglutinans and F. verticillioides. The same concentration<br />showed the inhibitory effect (MIC) on the growth of P. chrysogenum and P. aurantiogriseum.<br />The poorest effect of the caraway extract was expressed on the growth of A. niger, A.<br />versicolor, F. oxysporum and F. proliferatum.<br />The basil extract application in the concentration of 0.70 mL/100mL showed fungicidal effects<br />(MFC) on the growth of C. cladosporioides. The concentration of 1.50 mL/100mL completely<br />inhibited (MFC) the growth of A. wentii, A. versicolor, E. nidulans, E. herbariorum, E.<br />chevalierii, E. rubrum, P. chrysogenum and Fusarim spp. The poorest effect of the basil<br />extract was exhibited on A. niger, A. carbonarius, P. aurantiogriseum, E. amstelodami, P.<br />glabrum and P. brevicompactum.<br />The oregano extract showed the weakest growth inhibition influence on all of the tested<br />moulds. The application of this extract in the concentration of 1.50 mL/100mL was fungicidal<br />(MFC) to E. rubrum. The concentration of 2.50 mL/100mL showed fungicidal effects (MFC) on<br />the growth of E. rubrum, E. herbariorum, A. wentii, C. cladosporioides and P. aurantiogriseum<br />and inhibitory effects (MIC) on E. nidulans, E. chevalieri, E. amstelodami, P. glabrum and P.<br />brevicompactum. The weakest effect of this extract was expressed on the growth of A. niger,<br />A. carbonarius, F. proliferatum, F. subglutinans and P. chrysogenum.<br />Onion essential oil showed a significantly stronger antifungal effect on the tested moulds in<br />comparison to garlic essential oil. While the concentration of 14.0 mL/100mL of garlic oil had a<br />fungicidal effect on E. rubrum, E. chevalieri and C. cladosporioides, the same concentration<br />of onion oil was also fungicidal to E. herbariorum and E. amstelodami. With an exception of A.<br />niger and P. aurantiogriseum, the concentration that showed a fungicidal effect on the<br />remaining moulds equalled 28.0 mL/100mL.<br />Some of the tested mixtures of basil with caraway, basil with oregano, oregano with caraway,<br />and essential oils of onion and garlic, showed a synergistic effect on the growth inhibition of<br />A. wentii, E. herbariorum, F. verticilllioides and P. aurantiogriseum with the FIC index ranging<br />from 0.63 to 0.97.<br />Apart from the inhibitory effect on the mould colony growth, the spices extracts and the<br />essential oils of onion and garlic also caused changes in the macro- and micro- morphology<br />of the moulds.<br />Complete inhibition of the growth of A. versicolor and sterigmatocystin biosynthesis was<br />achieved at a concentration of 0.20 mL/100mL of the extract of caraway and oregano in the<br />period of 21 days. At this concentration the basil extract delayed the sterigmatocystin<br />biosynthesis by 88.73% while the mould growth was inhibited by 52.56%. Mixtures containing</p><p>75% of the caraway extract and 25% of the basil extract completely inhibited the mould<br />growth and sterigmatocystin biosynthesis in YES broth during 21 days of incubation.<br />The concentrations of 5.0 m L/100mL (onion essential oil) and 10.0 m L/100mL (garlic essential<br />oil) applied in a mixture containing 1.50 mL/100mL of onion and 0.50 mL/100mL of garlic<br />essential oil were necessary for a complete inhibition of the growth of A. versicolor and<br />sterigmatocystin biosynthesis.<br />The addition of the mixture of caraway and basil extracts (0.35 mL/100mL of caraway + 0.70<br />mL/100mL of basil) to fresh shredded cabbage influenced the reduction of initial mould<br />contamination by 93.9%. This was accompanied by the occurrence of acceptable more<br />intense flavour and slight discoloration.<br />The defined mathematical model for comparing the effects of extracts and essential oils on<br />the growth of moulds can be applied in establishing inhibition matrices and optimisation of<br />the time and the concentration of antifungal agents.<br />The obtained results on the antifungal effects of the spices extracts and onion and garlic<br />essential oils can be beneficial for improving the antifungal protection of food and reducing<br />the mycotoxin biosynthesis as well as the overall damage caused by the action of moulds.</p>
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Identifikacija Alternaria spp. na zrnu spelte i uticaj zaraze na komponenete prinosa, sadržaj mikotoksina i tehnološki kvalitet / Identification of Alternaria spp. on spelt kerenels and impact of infection on yield parameters, mycotoxins content and technological qualityĐisalov Jovana 11 December 2015 (has links)
<p>Savremeni trendovi na tržištu utiču na sve veću potražnju za speltom (Triticum aestivum ssp. spelta), alternativnom, plevičastom formom pšenice visoke nutritivne vrednosti, koja doprinosi održavanju agroekoloških sistema gajenja. Smatra se da prisustvo plevičastih omotača pruža zaštitu zrna od različitih bolesti i štetočina, što je od naročitog značaja za organsku proizvodnju gde upotreba hemijske zaštite nije dozvoljena. Rod Alternaria obuhvata veliki broj izrazito varijabilnih i široko rasprostranjenih saprofitnih i fitopatogenih vrsta. Značaj Alternaria spp. se ogleda ne samo u smanjenju prinosa i narušavanju kvaliteta zrna pšenice, već i u tome što mnoge vrste ovog roda produkuju toksične metabolite, koji su štetni za zdravlje ljudi i životinja. U cilju preduzimanja blagovremenih i efikasnih mera suzbijanja fitopatogenih vrsta roda Alternaria i monitoringa dominantnih toksigenih vrsta, veoma je značajna njihova pouzdana i prezicna identifikacija.<br />Istraživanja su obuhvatila identifikaciju i molekularnu karakterizaciju Alternaria spp. na zrnu spelte u Republici Srbiji uz analizu intenziteta zaraze posebno plevičastih i oljuštenih zrna spelte kako bi se ispitala efikasnost plavičastih omotača u zaštiti zrna spelte. Istovremeno je određen sadržaj najznačajnijih Alternaria toksina (alternariol-AOH i alternariol monometil-etar-AME), kao i sveobuhvatni uticaj ovih gljiva na komponente prinosa, zdravstvenu bezbednost i tehnološki kvalitet spelte. Izolovano je ukupno 25 Alternaria spp. sa zrna spelte roda 2011. god. iz različitih regiona Vojvodine i na osnovu morfoloških, patogenih i molekularnih karakteristika utvrđeno je prisustvo dve vrste: A. tenuissima (22 izolata) i A. infectoria (3 izolata). Dobijeni rezultati predstavljaju ujedno i prvo naučno saopštenje od vrstama roda Alternaria na spelti u Srbiji. Veštačkom inokulacijom tri različita genotipa spelte (Nirvana, Austria i Ostro) odabranim Alternaria izolatima u 2011. i 2012. god. uočena je značajna razlika u intenzitetu zaraze Alternaria spp. na zrnima sa plevičastim omotačima gde se intenzitet infekcije kretao od 87-100% dok je na oljuštenim zrnima iznosio od 16-72% u 2011. god., odnosno od 95-100% na plevičastim zrnima i 42-68% na oljuštenim zrnima u 2012. god. Efekat hemijske zaštite fungicidom se pokazao značajan za redukciju Alternaria spp. u obe istraživačke godine kako na plevičastim tako i na oljuštenim zrnima spelte. Kolorimetrijskim merenjima intenziteta zaraze plevičastih omotača i oljuštenih zrna inokulisanih biljaka u 2011. i 2012. god. potvrđena su standardna vizuelna fitopatološka ispitivanja, što ukazuje na to da se metoda instrumentale ocene zaraze može koristiti kao efikasna i brza metoda detekcije tamnokličnih zrna, gde uz dodatne verifikacije postoji mogućnost primene i u praksi. AOH i AME detektovani su u proseku četiri puta većoj koncentraciji u plevičastim omotačima nego u oljuštenim zrnima, što potvđuje efikasnost plevičastih omotača u zaštiti zrna spelte, ne samo od prodiranja Alternaria spp. već i od njihovih toksičnih metabolita. Najmanja koncentracija Alternaria toksina zabeležena je na oljuštenim zrnima bijaka tretiranih fungcidom (AOH - 84 μg/kg i AME - 153 μg/kg). Ispitivanja prometnog i tehnološkog kvaliteta spelte zaražene Alternaria spp. su pokazala da tamnoklična zrna značajno narušavaju parametre prometnog i tehnološkog kvaliteta spelte, negativno utičući na nalivanje i sazrevanje zrna kao i sintezu skroba i proteina.<br />Prikazani rezultati ukazuju na to da plevičasti omotači predstavljaju efikasnu barijeru u zaštiti zrna od infekcije vrstama roda Alternaria, što ima izuzetan značaj za otpornost spelte naročito u uslovima gajenja u sistemu organske proizvodnje gde upotreba hemijske zaštite nije dozvoljena. Međutim, uprkos prirodnoj otpornosti i genetskoj predodređenosti spelte za organsku proizvodnju, rezultati efikasne primene fungicida u suzbijanju Alternaria spp. opravdavaju adekvatan hemijski tretman u dobroj poljoprivrednoj praksi i proizvodnji zdravstveno bezbedne hrane. Multidisciplinarni pristup ove doktorske disertacije, ukazuje na neophodnost komplementarnog sagledavanja agronomskih i tehnoloških aspekata u poljoprivrednoj i prehrambenoj industriji, kao jedinstvenog modela koji omogućava praćenje savremenih tendencija u proizvodnji zdravstveno bezbedne hrane visokog nutritivnog kvaliteta.</p> / <p>There is an increasing market demand for alternative crops such as spelt wheat (Triticum aestivum ssp. spelta), an ancient, hulled with high nutritional values which<br />6<br />encourages agroecogical production systems. Accodrding to literture overview, it is considered that hulls protect kernels aginst different pests and pathogens, which is of great importance in organic production where chemical treatment is forbidden. Alternaria is a ubiquitous fungal genus that includes saprobic, and pathogenic species associated with yield losses and reduction of technological quality of small grains. Moreover, some of Alternaria spp. has high toxigenic potential and can be harmful for human and animal health. In order to conduct efficient disease control and monitoring of toxigenic Alternaria species, precise and reliable identification is highly important issue.<br />This study include identification and molecular characterisation of Alternaria spp. isolated from spelt kernels in the Republic of Serbia, followed by assessing of level of infection of hulled and dehulled kernels, separately. Additionally, the content of the most important Alternaria toxins (alternariol-AOH and alternariol monomethyl-etar-AME) is analysed, as well as the overall impact of infection on yield parameneters, food safety and technological quality of spelt wheat. Out of 25 Alternaria strains isolated from spelte kernels harvested in 2011. from different regions of Vojvodina and according to morphological, pathogenic and molecular characteristics, the most dominant species was A. tenuissima (22 isolates) followed by A. infectoria (3 isolates). This is the first report of Alternaria spp. detected on species level on spelt wheat in Serbia. After artificial inoculation of three different spelt genotypes (Nirvana, Austria i Ostro) with Alternaria isolates in 2011. and 2012., the sighnificant difference in the level of infection on hulled and dehulled kernels is noted. On the hulled kernels infection was in the range of 87-100%, while on the dehulled kernels was from 16 to 72% in 2011., and from 95 to 100% on hulled kernels and from 42 to 68% on dehulled kernels in 2012., respectivelly. Chemical treatment showed positive effect in the reduction of Alternaria disease in both years, on hulled and dehuled kernels as well. Colorimetric measurements of the level of infection proved conventional phytopatholoical analyses, which indicates that such instrumental method can be efficiently used in rapid detection of black point kernels and with additional verifications might be use in practise. AOH and AME were detected in four time higher concetrations in hulls compared to dehulled kernels, which confirms that hulls act as barriers against fungal infection and their toxic metabolities. The minimum concetration was detected on dehulled kernels treated with fungicide (AOH - 84 μg/kg i AME - 153 μg/kg). In the technological quality analysis of infected kernels, it was found that black point disease reduced tecnhnological quality, due to negeative impact of infection on maturation of grains and sinthesis of proteins and starch.<br />Presented results indicate that hulls on spelt kernels act as efficient barrires in the protection of kernels against Alternaria spp. and their toxic metabolities, which is of great importance for the resistance of spelt wheat particulary in the organic farming where chemical treatment is forbidden. Inspite of the fact that spelt is suitable for organic production, adequate fungicide application against Alternaria spp. is justified from the aspect of the good agriculture practise and food safety. Multidisciplinary approach of this doctoral dissertation points to necessity of complementary perception of agronomic and technological aspects in agriculture and food industry, as the unique model that supports contemporary trends in the production of food safety products with high nutritional value.</p>
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Microbiota fúngica e determinação de aflatoxinas em cultivar de amendoim plantado em diferentes regiões produtoras no estado de São Paulo. / Mycoflora and determination of aflatoxins in peanut variety grown in differents producing regions in the state of São Paulo.Atayde, Danielle Diniz 04 December 2009 (has links)
Os objetivos foram: identificar a microbiota fúngica e a ocorrência de aflatoxinas em cultivar de amendoim, identificar a microbiota fúngica do solo e correlacionar os resultados obtidos com os níveis de atividade de água encontrados. As amostras (solo e amendoim) foram provenientes de: Jaboticabal, Rosália, Tupã e Cafelândia (SP). A microbiota fúngica do solo revelou que o fungo do gênero Penicillium foi o mais frequente (52,1 %) nas quatro regiões durante as duas coletas (após a emergência das plantas e duas semanas antes do arranquio). Dentro do gênero Aspergillus, A. flavus foi a espécie mais frequente (13,5 %). A microbiota fúngica dos grãos e das cascas, das quatro regiões, nas duas coletas (duas semanas antes do arranquio e após o arranquio), demonstrou maior frequência de isolamento do fungo do gênero Fusarium (70,2 %). Do gênero Aspergillus, a espécie A. flavus foi a mais frequente (9,8 %). A análise de aflatoxinas revelou a presença de aflatoxinas em 5 % das amostras de grãos analisadas. Nas cascas, 13,75 % das amostras apresentaram contaminação por aflatoxinas. / The objectives were: to identify the mycoflora and the occurrence of aflatoxins in a peanut variety, identify the soil mycoflora and compare the acquired results with the levels of water activity found. The samples (peanut and soil) were collected from: Jaboticabal, Rosália, Tupã and Cafelândia (SP/Brazil). The mycoflora of the soil revealed that the genus Penicillium was the most frequent (52.1 %) in the four regions during the two trials (after the emergence of the plants and two weeks before the uprooting). Within the genus Aspergillus, A. flavus was the most frequent specie (13.5 %). The mycoflora of the kernels and peanut hulls, from the four regions in the two trials (two weeks before the uprooting and after the uprooting), demonstrated greater frequency of isolation of the genus Fusarium (70.2 %). Within the genus Aspergillus, A. flavus was the most frequent specie (9.8 %). The analysis of aflatoxins revealed the presence of aflatoxins in 5 % of the kernels samples analyzed. In peanut hulls, 13.75 % of the samples presented aflatoxin contamination.
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Adsorção multi-micotoxinas: revisão e estudo de carvões ativados / Multi-mycotoxin adsorption: review and study of activated carbonsCabral, Susana Maria 01 August 2019 (has links)
Elevada incidência de contaminação de micotoxinas em grãos de cereais e alimentos processados tem sido relatada em todo o mundo, principalmente em produtos destinados à alimentação animal. O objetivo desse trabalho foi explorar as tecnologias para redução das concentrações de micotoxinas, que estão disponíveis ou em desenvolvimento. A tecnologia de adsorção, assim como das metodologias disponíveis para avaliação in vitro da capacidade de adsorção foram abordadas com mais ênfase. Na etapa experimental deste projeto, avaliaram-se cinco carvões ativados quanto a suas propriedades e capacidade de adsorção de micotoxinas presentes individualmente e combinadas (multi-micotoxinas) (Aflatoxina B1, Desoxinivalenol, Fumonisina B1 e Zearalenona). O carvão que apresentou maior capacidade de adsorção multi-micotoxinas foi selecionado para um estudo das interações entre adsorvente/adsorvato e possíveis fatores interferentes. Foram avaliados parâmetros físico-químicos do carvão, o efeito do tempo de contato, efeito dose, isotermas e efeito da composição do meio e da mudança do pH. A adsorção de Aflatoxina B1 e Zearalenona não sofreu efeito dos fatores estudados, diferente da adsorção de Fumonisina B1 e Desoxinivalenol. Os resultados auxiliam na análise da interação das moléculas de micotoxinas e do carvão ativado, bem como de quais fatores podem afetar o processo de adsorção de cada uma delas. Porém mais estudos são necessários para esclarecer melhor o papel de cada um dos fatores na adsorção das micotoxinas aqui estudadas. / The high incidence of mycotoxins contamination in cereal grains and processed foods have been reported worldwide, especially in products intended for animal feed. The objective of this work was to explore the available and upcoming technologies applied for the reduction of mycotoxins present in foods with a focus on adsorption, as well as in the in vitro methodology. Following, five activated carbon were evaluated about their properties and its individual and multi-mycotoxin adsorption capacity (Aflatoxin B1, Deoxynivalenol, Fuminisin B1 and Zearalenone). The activated carbon that presented the highest capacity of multi-mycotoxin adsorption was selected to continue the study in order to explore the interactions between adsorbent / adsorbate and possible interferents. Physicochemical parameters were evaluated, the effect of the contact time, concentration, isotherms and effect of the composition of the medium and the pH change. The adsorption of Aflatoxin B1 and Zearalenone had no effect of the factors studied, different from the adsorption of Fumonisin B1 and Deoxynivalenol. The results help in the analysis of the interaction of mycotoxins and activated carbon molecules, as well as which factors may affect the adsorption process of each of them. However, more studies are needed to clarify the role of each of the factors in the adsorption of these mycotoxins studied.
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Exposure assessment to multiple mycotoxins in rural areas of São Paulo and Santa Catarina states, Brazil / Avaliação da exposição a múltiplas micotoxinas em áreas rurais dos estados de São Paulo e Santa Catarina, BrasilFranco, Larissa Tuanny 15 February 2019 (has links)
Mycotoxins are secondary metabolites produced by fungi that occur naturally in foodstuffs, which can cause a large variety of toxic effects on vertebrates including humans. The objectives of this work were to evaluate the co-occurrence of 11 mycotoxins in food products, feed for broiler chicks, laying hens and dairy cattle, assess the human exposure to mycotoxins through food analysis versus consumption data and multimycotoxin biomarkers in urine, and characterize the associated risk of mycotoxin exposure in Brazilian rural areas. Sampling procedures were conducted in 38 small-scale dairy and poultry farms in the surroundings of Pirassununga and Descalvado (State of São Paulo), Pinhalzinho and Erval Velho (State of Santa Catarina). In these farms a total of 86 volunteers were recruited and instructed to provide samples of the morning urine (N = 162) in two sampling periods (April-May/2016 and December/2016), along with samples of rice (N = 66), bean (N = 59), wheat (N = 39), corn flour (N = 21) and corn meal (N = 18) available in their households. Samples of feed for broilers (N = 10), laying hens (N = 20) and dairy cattle (N = 15) were also collected. All samples were analyzed by ultra-performance liquid chromatography coupled to mass spectrometry (UPLC-MS/MS) for determination of aflatoxins (AF) B1, B2, G1 and G2, fumonisins (F) B1 and B2, ochratoxin A (OTA), zearalenone (ZEN), deoxynivalenol (DON), toxin T-2 and toxin HT-2 in food products and feeds, and AFM1, AFP1, AFQ1, FB1, OTA, T-2, HT-2, DON, de-epoxideoxynivalenol (DOM-1), ZEN, α-zearalenol (α-ZEL), β-zearalenol (β-ZEL) and 15-acetyl-DON in urine samples. The mycotoxin levels in urine were adjusted to creatinine concentration in each sample analyzed. In feed samples, median levels of total AF, total FB, ZEN and DON were 100 µg/kg, 680 µg/kg, 160 µg/kg and 200 µg/kg, respectively. The co-occurrence of two or more mycotoxins was confirmed in 51% of feed samples. Results indicate a high exposure of farm animals to mycotoxins in the feed, hence emphasizing the need to improve the feed quality regarding the contamination with mycotoxins in small-scale farms in Brazil, and the necessity of include feed in Brazilian regulation, especially for AF, FB, and ZEN. Mycotoxin levels above the Brazilian maximum permitted levels (MPL) were found in rice (1.5%), wheat flour (12.8%) and corn flour (14.3%) samples. Urine determinations revealed the presence of AFM1 and AFP1, DON, OTA, FB1 and ZEN at levels of 0.02-12.0 ng/mg creatinine. Regarding the probable daily intake (PDI) based on food data, only ZEN (0.156 µg/kg b.w./day) had a Hazard Quotient (HQ) above the tolerance (> 1). PDI values based on urinary levels for DON, OTA and total AF were 84.914, 0.031 and 0.001 µg/kg b.w./day, respectively, resulting in HQ values > 1, which may indicate health risks for the population studied. An informal intervention by means of educational activities and delivery of an information flyer during the first sampling period did not change the exposure levels to mycotoxins in the second sampling period. Further studies are needed to identify food items other than those analyzed in this work as sources of dietary mycotoxins, as well as the contribution of inhalation of contaminated dusts for the exposure. This is the first study to report the risk assessment of mycotoxins based on food and urinary levels in rural areas in Brazil. / As micotoxinas são metabólitos secundários produzidos por fungos que ocorrem naturalmente em alimentos, das quais podem causar uma grande variedade de efeitos tóxicos em vertebrados, incluindo humanos. Os objetivos deste trabalho foram avaliar a co-ocorrência de 11 micotoxinas em alimentos, rações para frangos de corte, poedeiras e gado leiteiro, avaliar a exposição humana a micotoxinas através de análise de alimentos versus dados de consumo e biomarcadores de múltiplas micotoxinas na urina, e caracterizar o risco associado de exposição a micotoxinas em áreas rurais brasileiras. Os procedimentos de amostragem foram conduzidos em 38 propriedades leiteiras e avícolas de pequeno porte nos arredores de Pirassununga e Descalvado (SP), Pinhalzinho e Erval Velho (SC). Nestas fazendas, um total de 86 voluntários foram recrutados e instruídos a fornecer amostras da primeira urina da manhã (N = 162) em dois períodos de amostragem (abril-maio/2016 e dezembro/2016), juntamente com amostras de arroz (N = 66) , feijão (N = 59), trigo (N = 39), farinha de milho (N = 21) e fubá (N = 18) disponíveis em suas residências. Amostras de ração para frangos de corte (N = 10), poedeiras (N = 20) e bovinos leiteiros (N = 15) também foram coletadas. Todas as amostras foram analisadas por cromatografia líquida de ultra-performance acoplada a espectrometria de massas (UPLC-MS/MS) para determinação de aflatoxinas (AF) B1, B2, G1 e G2, fumonisina (FB) B1 e B2, ocratoxina A (OTA), zearalenona (ZEN), desoxinivalenol (DON), toxina T-2 e toxina HT-2 em produtos alimentícios e rações, e AFM1, AFP1, AFQ1, FB1, OTA, T-2, HT-2, DON, de-epóxido-oxinivalenol (DOM-1), ZEN, α-zearalenol (α-ZEL), β-zearalenol (β-ZEL) e 15-acetil-DON em amostras de urina. Os níveis de micotoxinas na urina foram ajustados à concentração de creatinina em cada amostra analisada. Em amostras de ração, os níveis médios de AF total, FB total, ZEN e DON foram de 100 µg/kg, 680 µg/kg, 160 µg/kg e 200 µg/kg, respectivamente. A co-ocorrência de duas ou mais micotoxinas foi confirmada em 51% das amostras de ração. Os resultados indicam uma alta exposição de animais de fazenda à micotoxinas na ração, enfatizando a necessidade de melhorar a qualidade das rações em fazendas de pequena escala no Brasil, referente as micotoxinas, e a necessidade de incluir ração na legislação brasileira, especialmente para AF, FB e ZEN. Os níveis de micotoxinas acima dos níveis máximos permitidos no Brasil (LMP) foram encontrados em arroz (1,5%), farinha de trigo (12,8%) e farinha de milho (14,3%). As determinações da urina revelaram a presença de AFM1 e AFP1, DON, OTA, FB1 e ZEN nos níveis de 0,02-12,0 ng/mg de creatinina. Em relação à ingestão provável diária (IPD) com base em dados de alimentos, apenas ZEN (0,156 µg/kg p.c./dia) apresentou um Quociente de Risco (HQ) acima do tolerável (> 1). Os valores de IPD baseados nos níveis urinários para DON, OTA e AF total foram 84,914, 0,031 e 0,001 µg/kg p.c./dia, respectivamente, resultando em valores de HQ> 1, o que pode indicar riscos para a saúde da população estudada. Uma intervenção informal por meio de atividades educacionais e entrega de um folheto informativo durante o primeiro período de amostragem não alterou os níveis de exposição às micotoxinas no segundo período de amostragem. Mais estudos são necessários para identificar itens alimentares além dos analisados neste trabalho como fontes de micotoxinas diárias, bem como a contribuição da inalação de pós contaminados para a exposição. Este é o primeiro estudo a relatar a avaliação de risco de micotoxinas com base em alimentos e níveis urinários em áreas rurais no Brasil.
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Evidence for the involvement of a mitochondrial permeability transistion in a victorin-Induced cell deathCurtis, Marc James 27 March 2003 (has links)
Graduation date: 2003
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Genetic and biochemical analysis of Victoria blight : identification of AFLP markers and purification and characterization of the oat saspaseCoffeen, Warren C. 16 May 2003 (has links)
Graduation date: 2003
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