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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.
21

AlteraÃÃes hematolÃgicas e funcionais causadas por venenos de subespÃcies brasileiras de Crotalus durissus e suas fraÃÃes isoladas / HematolÃgicas and functional alterations caused by venom of Brazilian subspecies of Crotalus durissus and its isolated fractions

IÃda Pereira de Souza 27 November 2006 (has links)
FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / Os acidentes ofÃdicos de serpentes representam um sÃrio problema de SaÃde PÃblica nos paÃses tropicais, tanto pela freqÃÃncia com que ocorrem e/ou pela morbi-mortalidade que ocasionam. As serpentes do gÃnero Crotalus estÃo representadas no Brasil pela espÃcie Crotalus durissus, a qual se divide em seis subespÃcies. Nosso trabalho teve como objetivo avaliar os efeitos dos venenos das serpentes Crotalus durissus cascavella originadas do estado do Cearà (Cdcc) e MaranhÃo (Cdcm); Crotalus durissus collilineatus (Cdcol); Crotalus durissus ruruima (Cdru) e suas fraÃÃes, Crotoxina (CTXru) e Fosfolipase A2 (PLA2ru), nos processos biolÃgicos de espraiamento celular, fagocitose, atividade fungicida e alteraÃÃes hematolÃgicas. Camundongos Swiss, machos, foram inoculados por via intraperitonial com os venenos descritos acima, nas doses de 120, 50, 27, 20 (venenos) e 10Âg/Kg (fraÃÃes), respectivamente. Duas horas apÃs inoculaÃÃo foram coletadas amostras de sangue do plexo orbital e o exsudato peritonial. A anÃlise estatÃstica utilizada foi o teste t de Student com significÃncia de 95%. Os animais tratados foram comparados com o grupo controle (inoculados com salina 0,9%). Cdcm e a CTXru causaram as maiores alteraÃÃes no eritrograma. 37,5% dos eritrÃcitos apresentaram morfologia macrocÃtica e microcÃtica; 25,5% hipocrÃmia; 25% com anisocitose e presenÃa de policromasia. Foram observados 16,8% de corpÃsculos de Howell Jolly. A contagem global de leucÃcitos foi reduzida significantemente apÃs administraÃÃo do Cdcc (82,9%), Cdcm (70,1%) e Cdru (83,8%). A celularidade foi alterada depois da inoculaÃÃo de Cdcc, Cdru e CTXru, em todos os tipos de cÃlulas. A contagem global de cÃlulas do peritÃnio aumentou apÃs inoculaÃÃo de Cdcc, Cdcol, Cdru e a CTXru. Em adiÃÃo, o macrÃfago foi à cÃlula predominante na contagem diferencial de cÃlulas peritoniais, contudo, somente a Cdcol apresentou significÃncia estatÃstica para macrÃfago (62,3%). Foi encontrada reduÃÃo significativa do espraiamento celular depois da administraÃÃo de todos os venenos variando de 52,7 a 65,7%. A fagocitose foi estatisticamente reduzida pela Cdcc nos perÃodos de 30, 60, 90 e 120 minutos. Cdru reduziu a fagocitose apenas em 30, 60 e 120 minutos, Cdcm em 30 e 90 minutos e CTXru nos tempos de 60 e 120 minutos. A Cdcol, e a CTXru mostraram significÃncia na atividade fungicida contra C. albicans nos perÃodos de 30, 60, 90 e 120 minutos, mas a Cdcc mostrou resultado similar em 60, 90 e 120 minutos. Conclui-se que o veneno interfere diferentemente na resposta hematolÃgica e funcional. Em adiÃÃo pode-se postular que os macrÃfagos foram responsÃveis por estas alteraÃÃes. Estudos futuros deverÃo ser realizados na perspectiva da identificaÃÃo de provÃvel aÃÃo fungicida de venenos ofÃdicos e suas fraÃÃes / Venomous snake accidents represent a serious public health problem in tropical countries, as much as for their frequency of occurrence and/or morbidity and mortality that they caused. In Brazil, the genus Crotalus comprise only one species, termed Crotalus durissus, which is divided into six subspecies. The aim of our study was to evaluate the effects promoted by venoms of Crotalus durissus cascavella, originated from the States of Cearà (Cdcc) and MaranhÃo (Cdcm); C. durissus collilineatus (Cdcol); C. durissus ruruima (Cdru) and its isolated components, such as crotoxin (CTXru) and phospholipase A2 (PLA2ru), in the biological processes of cellular spreading, phagocytosis, hematological alterations and antifungal activity. Male Swiss mice were inoculated intraperitoneally with the venom doses of 120, 50, 27, 20, 10 and 10 Âg/Kg, respectively to the snakes described above. After two hours of inoculation blood samples and exudate were collected from orbital plex and peritoneum, respectively. Statistical evaluation was performed using Student-T test with significance level set at 95%. We compared the treated animals with a control group, where animals were inoculated with saline 0.9%. Cdcm and CTXru caused the most severe alterations in the erythrogram. We noticed that 37.5% of the erythrocytes showed macrocytic and microcytic morphology; 25.5% were hipocromic; 25% showed anisocytosis and the presence of polycromasia. We also found Howell Jolly bodies in 16.8% of the examined erythocytes. The total counting of leukocytes was reduced statistically after administration of Cdcc (82.9%), Cdcm (70.1%) and Cdru (83.8%). Cellularity was altered after the inoculation of Cdcc, Cdru and CTXru for all evaluated cells. We noticed a statistic increase of peritoneum total cells caused by Cdcc, Cdcol, Cdru and CTXru. In addition, macrophage was the most predominant cell after peritoneum differential cell counting. However, only Cdcol showed a statistic increase of macrophages (62.3%). We found significant reduction of cellular spreading after administration of all venoms ranging from 52.7 to 65.7%. Phagocytosis was statistically reduced by Cdcc in the periods of 30, 60, 90 and 120 minutes. However, Cdru reduced phagocytosis only at 30, 60 and 90 minutes, Cdcm decreased phagocytosis at 30 and 90 minutes and CTXru in the periods of 60 and 120 minutes. Cdcol and CTXru showed significant fungicide activity against C. albicans in the periods of 30, 60, 90 and 120 minutes, but Cdcc showed similar results at 60, 90 and 120 minutes. We conclude that distinct venoms interfered differently in the intensity of each functional and hematological response. In addition, we postulate that macrophages maybe partially responsible for these alterations. Further studies should be evaluated for the use of venoms as fungicides
22

Atividade citotóxica de naftoquinonas semisintéticas em espécies de Cândida isoladas da cavidade oral

Freire, Cristina Pessoa Veloso 09 June 2010 (has links)
Made available in DSpace on 2015-04-22T22:14:14Z (GMT). No. of bitstreams: 1 Cristina Pessoa Veloso Freire.pdf: 2819799 bytes, checksum: 8919fceb66aefa886139385d2b54aae1 (MD5) Previous issue date: 2010-06-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / the species most frequently at least seven species, has been associated with diseases in humans: Candida albicans, Candida. tropicalis, Candida stellatoidea, Candida pseudotropicalis (now called C. Kefyr), Candida parapsilosis, Candida guilliermondii and Candida krusei. There is an increased occurrence of infections by Candida species, caused by population growth that immunosuppression with high predisposition to develop infections. Also, there was an increased use of antifungal agents, where some Candida showed a decline in sensitivity to these agents. Increasing numbers of fungal strains are becoming resistant to the drugs available. As a result, there is a constant search for new antifungal drugs more effective and safer than existing ones. The naphthoquinones are widely distributed in nature, with the known activities, the antibacterial, antifungal and antitumor. Thus the objective of this study was to evaluate the antifungal activity and cytotoxicity of naphthoquinones semisynthetic in Candida strains isolated from the oral cavity. The strains studied were C. albicans, C. krusei, C. parapsilosis, C. kefyr, C. tropicalis and C. dubliniensis. The susceptibility of semi-synthetic naphthoquinones was tested initially by using the simple diffusion from the hole in the culture medium (hole plate), to obtain a quantitative analysis, and then for a quantitative analysis technique was used in broth. Patterns known antifungals were used, for comparison of antifungal activity. The semi-synthetic naphthoquinone that showed the best antifungal activity in the hole plate technique was NORALFA, followed by IVS322 with average of inhibition zone against C. albicans 21,26 mm and 16,62 mm respectively, and quantitative analysis of antifungal activity, substances NORALFA and IVS322 stood out with MIC against C. albicans 0,125 μg/ml and 0.5 μg/ml. It was found that none of the substances tested at a concentration of 50 μg/ml caused hemolysis and fibroblasts tested remained viable at a concentration of 12,5 μg/ml. This result is favorable, since the hemolysis test is a measure of toxicity and a positive result would preclude the therapeutic use of these substances. Through this work we determine the potential antifungal and cytotoxic profile of the compounds tested. / A candidíase é uma doença infecciosa causada pelo fungo Candida, sendo a espécie albicans a mais freqüentes. Sete espécies pelo menos, tem sido associadas a doenças no homem: Candida albicans, Candida. tropicalis, Candida stellatoidea, Candida peseudotropicalis (hoje chamada de C. Kefyr), Candida parapsilosis, Candida guilliermondii e Candida krusei. Há um aumento da ocorrência das infecções por espécies de Candida, causada pelo crescimento da população com imunodepressão que grande predisposição ao desenvolvimento de infecções.Números cada vez maiores de cepas fúngicas estão se tornando resistentes aos fármacos disponíveis no mercado. Em virtude disso, existe uma constante procura de novos fármacos antifúngicos mais eficazes, e mais seguros que os já existentes. As naftoquinonas são amplamente distribuídas na natureza, tendo como atividades conhecidas, a atividade antibacteriana, antifúngica e antitumoral. Desta forma o objetivo deste estudo foi avaliar a atividade antifúngica e citotoxicidade de naftoquinonas semi-sintéticas em cepas de Candida isoladas da cavidade oral. As cepas estudadas foram de C. albicans, C. krusei, C. parapsilosis, C. kefyr, C. tropicalis e C. dubliniensis. A suscetibilidade das naftoquinonas semisintéticas foi testada inicialmente, através do teste difusão a partir de orifício no meio de cultura (hole plate). Posteriormente para uma analise quantitativa foi utilizada a técnica de microdiluição em caldo. Padrões antifúngicos conhecidos foram usados, para comparação da atividade antifúngica. A citotoxicidade foi avaliada em hemácias de camundongos através do teste de hemólise e através do teste de viabilidade celular em fibroblastos, utilizando o Alamar Blue. A naftoquinona semisintética que apresentou melhor atividade antifúngica na técnica hole plate foi a NORALFA, seguida da IVS322 com médias do halo de inibição frente a C. albicans de 21,26 e 16,62 mm respectivamente, e na análise quantitativa da atividade antifúngica, as substâncias NORALFA e IVS322 se destacaram com CIM frente a C. albicans 0, 125 μg/ml e 0,5 μg/ml. Verificou-se que nenhuma das substâncias testadas a uma concentração de 50 μL/ml provocou hemólise e os fibroblastos testados permaneceram viáveis na concentração de 12,5 μL/ml. Este resultado é favorável, uma vez que o teste de hemólise é um parâmetro de toxicidade e um resultado positivo poderia impossibilitar o uso terapêutico dessas substâncias. Com a realização deste trabalho conseguimos determinar o potencial antifúngico e o perfil citotóxico das substâncias testadas.
23

Verifica??o da atividade antif?ngica de extratos aquosos de Cymbopogon citratus, Peumus boldus e Shinus terebinthifolia sobre cinco esp?cies de fungos do g?nero Aspergillus. / Verification of antifungal activity of aqueous extracts of Cymbopogon citratus, Peumus boldus and Shinus terebinthifolia on five species of fungi of the genus Aspergillus

Santos, Alexander 15 April 2008 (has links)
Made available in DSpace on 2016-04-28T20:17:28Z (GMT). No. of bitstreams: 1 2008 - Alexander Santos.pdf: 2028526 bytes, checksum: 5876d3f1d1f305df3af598f0bef1531d (MD5) Previous issue date: 2008-04-15 / This work was developed in the Department of Microbiology and Immunology of the Institute of Veterinary Rural Federal University of Rio de Janeiro in Serop?dica-RJ. We evaluated the antifungal activity plant Cymbopogon citratus (lemon-grass), Peumus boldus (boldo) and Shinus terebinthifolia (aroeira), inhibition of growth of species of the genus Aspergillus (A. flavus, A. niger, A. ochraceus, A. Parasiticus and A. carbonarius. Using the method of minimum inhibitory concentration in agar, with the technique of dilution plate (Pour-Plate), were held dilutions of different extracts, resulting in the final concentrations of 5%, 2.5% and 1.25%. Testing of commercial sensitivity to antifungal - ketoconazole were made in a final concentration of 1933.18 ? g /mL, as recommended by the National Committee for Clinical Laboratory Standards (NCCLS). The results obtained in the experiments have shown that aqueous extracts of C. citratus and S. terebinthifolia, after 24 hours of incubation, were able to inhibit the growth of A. flavus and A. carbonarius, respectively. The other extracts being studied and tested in the concentrations were not able to inhibit the growth of mycelial species of the genus Aspergillus. / Este trabalho foi desenvolvido no Departamento de Microbiologia e Imunologia do Instituto de Veterin?ria da Universidade Federal Rural do Rio de Janeiro, em Serop?dica-RJ. Foram avaliadas a atividade antif?ngica das plantas Cymbopogon citratus (capim-lim?o), Peumus boldus (boldo) e Shinus terebinthifolia (aroeira), na inibi??o do crescimento de esp?cies do g?nero Aspergillus (A. flavus, A. niger, A. ochraceus, A. parasiticus e A. carbonarius). Utilizando o m?todo da concentra??o inibit?ria m?nima em ?gar, com a t?cnica de dilui??o em placa (Pour-Plate), foram realizadas dilui??es dos diferentes extratos, obtendo-se as concentra??es finais de 5%, 2,5% e 1,25%. Testes de sensibilidade ao antif?ngico comercial - cetoconazol foram realizados numa concentra??o final de 1933,18 ?g/mL, conforme recomendada pelo National Committee for Clinical Laboratory Standards (NCCLS). Os resultados obtidos nos experimentos demonstraram que os extratos aquosos de C. citratus e S. terebinthifolia, ap?s 24 horas de incuba??o, foram capazes de inibir o crescimento de A. flavus e A. carbonarius, respectivamente. Os demais extratos em estudo e nas concentra??es testadas, n?o foram capazes de inibir o crescimento micelial das esp?cies do g?nero Aspergillus.
24

Uticaj ekstrakata žačina na rast plesni i biosintezu mikotoksina / The effect of spice extracts on the growth of moulds and mycotoxinbiosynthesis

Kocić-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&acute;102 cfu/g, u uzorcima poslastičarskih proizvoda do 6,1&acute;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&acute;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%), proizvo&ntilde;ači 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>Mikotoksikolo&scaron;kim ispitivanjem hrane u dva uzorka salata spremnih za konzumiranje<br />(kupus beli rezani i FIT salata) utvr&ntilde;en je sadržaj sterigmatocistina u koncentracijama od 3,5<br />i 5,5 mg/kg.<br />Kao glavna komponenta u ekstraktu kima odre&ntilde;en 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 />odre&ntilde;ene 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 sme&scaron;a 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%. Sme&scaron;a 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 sme&scaron;i<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 sme&scaron;e 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 pobolj&scaron;anju antifungalne za&scaron;tite namirnica, smanjenju biosinteze<br />mikotoksina i ukupnim smanjenju &scaron;teta 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 &ldquo;ready for use&rdquo; ranged<br />from 10.0 to 5.5&acute;102 cfu/g. In cake and pastries, as well as, meat samples, the number<br />reached 6.1&acute;102 cfu/g and 60.0 cfu/g, respectively. The highest number of mould colonies was<br />isolated in DG18 medium (1.53 &acute; 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 &quot;ready for use&quot; (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) &ndash; 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>
25

Synthesis and evaluation of selected benzimidazole derivatives as potential antimicrobial agents : an investigation into the synthesis of substituted benzimidazoles and their evaluation in vitro for antimicrobial activity

Alasmary, Fatmah Ali Saeed January 2013 (has links)
Microbe resistence is a serious issue, especially as they have become resistant to most well known drugs. Therefore this is considered as a global problem and is now dealt with at a poitical level. Since no new classes of antimicrobial agents have been discovered in the past three deacdes, the development of new drugs is extremely urgent. Therefore the aim of this project was to synthesise derivatives of benzimidazole, and then assesses their antimicrobial activities in vitro by using disc (well) diffusion and MICs tests. A total of 69 benzimidazole derivatives, with substituents at positions 1, 2, and 5, were synthesised, characterised and tested against selected bacteria and fungi. In addition, six bezimidazole silver complexes were prepared and evaluated for their antimicrobial behavior. The SAR showed that the antimicrobial activity of the compounds depended on the substituents attached to the bicyclic heterocycle. Some promising results were obtained. In particular, 5 compounds displayed antibacterial activity against two MRSA strains with MIC values corresponding to ciprofloxacin, which can be considered significant. The compounds have some common features; four possess 5-chloro or 5-bromo substituents; two are derivatives of (S)-2- ethanaminebenzimidazole and the others are derivative of one 2-(chloromethyl)-1Hbenzo[d]imidazole, (1H-benzo[d]imidazol-2-yl)methanethiol and 2-(methoxymethyl)-1-methyl-1H-benzo[d]imidazole. The results from the antifungal screening were very interesting as there were 26 compounds, including two silver complexes, which were potent fungicides against the selected fungal species. They showed equivalent or greater potentency in their MIC values than amphotericin B. In particular, the 5-fluoro, 5-chloro and 5-bromo benzimidazole showed broad spectrum activity.
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Naujų 4-tiazolidinonų, turinčių sulfanilamido, alilamino ir nitrofurano farmakoforus, priešmikrobinių savybių tyrimas / New 4-thiazolidinones, containing sulfanilamide, allylamine and nitrofurane pharmacophores and evaluation of their antimicrobial activity

Ževžikovienė, Augusta 18 September 2012 (has links)
Klinikinėje praktikoje infekcinėms ligoms gydyti vartojama daugiau kaip 200 priešmikrobinių medžiagų, tačiau infekcinės ligos yra viena dažniausių mirties priežasčių ir naujų priešmikrobinių vaistų poreikis nemažėja. Modifikuojant 4-tiazolidinono žiedą susintetinami įvairaus biologinio aktyvumo junginiai. 4-tiazolidinono dariniai su sulfanilamido farmakoforu yra aktyvesni už sulfanilamidus prieš bakterijas ir pasižymi priešgrybeliniu poveikiu; su nitrofurano farmakoforu yra vieni aktyviausių priešmikrobinių junginių. Alilaminą įjungus į molekulę kartu su jau anksčiau žinomais farmakoforais, tikėtąsi geresnio naujų junginių priešmikrobinio aktyvumo. Pritaikius pasirinktas metodikas naujų 4-tiazolidinono darinių su pasirinktų farmakoforų (sulfanilamido, nitrofurano, alilamino) struktūriniais fragmentais sintezei, susintetinti 39 4-tiazolidinono ciklą turintys junginiai. Įvertinus fiziko-chemines savybes ir toksiškumo riziką in silico, nustatyta junginių, kaip biologiškai aktyvių medžiagų, vertė. In silico ir in vitro patvirtinta, kad nauji 4-tiazolidinono dariniai su sulfanilamido, nitrofurano ir alilamino farmakoforais pasižymi prieš¬mikrobinėmis savybėmis prieš skirtingas bakterijų (S. aureus, E. faecalis, E. coli, P. aeruginosa, K. pneumonia, B. subtilis, P. mirabilis) ir grybelio C.albicans kultūras. Apibendrinus mikrobiologinių tyrimų rezultatus, nustatyti aktyviausi antibakteriniai ir priešgrybeliniai junginiai. / More than 200 antimicrobial agents are used in clinical practice for the treatment of infectious diseases, however, infectious diseases are still one of the most common causes of death, and the need for new antimicrobials isn’t decreasing. Compounds with different biological activity are synthesized by modifying 4-thiazolidinone. 4-thiazolidinones with sulfanilamide pharmacophore are more active against bacteria than sulfanilamides, and are characterized as antifungals. 4-thiazolidinones with nitrofuran pharmacophore are one of the most active antimicrobials. Higher antimicrobial activity of new compounds was expected after attaching allylamine to the molecule together with the previously known pharmacophores. By applying the selected methodologies for the synthesis of new 4-thiazolidinones with the fragments of selected pharmacophores (sulfanilamide, nitrofurane, allylamine), 39 derivatives of 4-thiazolidinone were synthesized. The assessment of physico-chemical properties and toxicity risk in silico helped to determine the value of compounds as biologically active substances. In silico and in vitro studies confirmed that new 4-thiazolidinone’s with sulfanilamide, nitrofurane and allylamine pharmacophores showed antimicrobial activity against various bacteria (S. aureus, E. faecalis, E. coli, P. aeruginosa, K. pneumonia, B. subtilis, P. mirabilis) and fungal cultures of C.albicans. Summarising microbiological tests, the most active antibacterial and antifungal compounds... [to full text]
27

Naujų 4-tiazolidinonų, turinčių sulfanilamido, alilamino ir nitrofurano farmakoforus, priešmikrobinių savybių tyrimas / New 4-thiazolidinones, containing sulfanilamide, allylamine and nitrofurane pharmacophores and evaluation of their antimicrobial activity

Ževžikovienė, Augusta 18 September 2012 (has links)
Klinikinėje praktikoje infekcinėms ligoms gydyti vartojama daugiau kaip 200 priešmikrobinių medžiagų, tačiau infekcinės ligos yra viena dažniausių mirties priežasčių ir naujų priešmikrobinių vaistų poreikis nemažėja. Modifikuojant 4-tiazolidinono žiedą susintetinami įvairaus biologinio aktyvumo junginiai. 4-tiazolidinono dariniai su sulfanilamido farmakoforu yra aktyvesni už sulfanilamidus prieš bakterijas ir pasižymi priešgrybeliniu poveikiu; su nitrofurano farmakoforu yra vieni aktyviausių priešmikrobinių junginių. Alilaminą įjungus į molekulę kartu su jau anksčiau žinomais farmakoforais, tikėtąsi geresnio naujų junginių priešmikrobinio aktyvumo. Pritaikius pasirinktas metodikas naujų 4-tiazolidinono darinių su pasirinktų farmakoforų (sulfanilamido, nitrofurano, alilamino) struktūriniais fragmentais sintezei, susintetinti 39 4-tiazolidinono ciklą turintys junginiai. Įvertinus fiziko-chemines savybes ir toksiškumo riziką in silico, nustatyta junginių, kaip biologiškai aktyvių medžiagų, vertė. In silico ir in vitro patvirtinta, kad nauji 4-tiazolidinono dariniai su sulfanilamido, nitrofurano ir alilamino farmakoforais pasižymi prieš¬mikrobinėmis savybėmis prieš skirtingas bakterijų (S. aureus, E. faecalis, E. coli, P. aeruginosa, K. pneumonia, B. subtilis, P. mirabilis) ir grybelio C.albicans kultūras. Apibendrinus mikrobiologinių tyrimų rezultatus, nustatyti aktyviausi antibakteriniai ir priešgrybeliniai junginiai. / More than 200 antimicrobial agents are used in clinical practice for the treatment of infectious diseases, however, infectious diseases are still one of the most common causes of death, and the need for new antimicrobials isn’t decreasing. Compounds with different biological activity are synthesized by modifying 4-thiazolidinone. 4-thiazolidinones with sulfanilamide pharmacophore are more active against bacteria than sulfanilamides, and are characterized as antifungals. 4-thiazolidinones with nitrofuran pharmacophore are one of the most active antimicrobials. Higher antimicrobial activity of new compounds was expected after attaching allylamine to the molecule together with the previously known pharmacophores. By applying the selected methodologies for the synthesis of new 4-thiazolidinones with the fragments of selected pharmacophores (sulfanilamide, nitrofurane, allylamine), 39 derivatives of 4-thiazolidinone were synthesized. The assessment of physico-chemical properties and toxicity risk in silico helped to determine the value of compounds as biologically active substances. In silico and in vitro studies confirmed that new 4-thiazolidinone’s with sulfanilamide, nitrofurane and allylamine pharmacophores showed antimicrobial activity against various bacteria (S. aureus, E. faecalis, E. coli, P. aeruginosa, K. pneumonia, B. subtilis, P. mirabilis) and fungal cultures of C.albicans. Summarising microbiological tests, the most active antibacterial and antifungal compounds... [to full text]
28

Avaliação da atividade antifúngica do Cloridrato de Verapamil frente a leveduras do gênero Candida / Evaluation of the antifungal activity of Verapamil Hydrochloride against yeasts of the genus Candida

Oliveira, Priscila dos Santos 06 August 2018 (has links)
Submitted by Priscila dos Santos Oliveira (priscilaspitty@hotmail.com) on 2018-08-29T22:43:22Z No. of bitstreams: 1 Merged_Priscila Oliveira.pdf: 1205779 bytes, checksum: 2ed8db0dfdefdc0a97d7a31fad8acaa9 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-09-03T14:47:25Z (GMT) No. of bitstreams: 1 Oliveira_mp_me_sjc.pdf: 1205779 bytes, checksum: 2ed8db0dfdefdc0a97d7a31fad8acaa9 (MD5) / Made available in DSpace on 2018-09-03T14:47:25Z (GMT). No. of bitstreams: 1 Oliveira_mp_me_sjc.pdf: 1205779 bytes, checksum: 2ed8db0dfdefdc0a97d7a31fad8acaa9 (MD5) Previous issue date: 2018-08-06 / Resumo: A epidemiologia das infecções causadas por Candida sofreu mudanças nos últimos anos. Embora Candida albicans ainda seja o principal patógeno causador de candidíase, relatos recentes reportam o aumento da incidência de infecções causadas por espécies de Candida não-albicans. A toxicidade dos fármacos antifúngicos utilizados juntamente com o desenvolvimento da resistência tem se tornado um sério problema clínico. Com isso, atualmente existe a urgência na descoberta de novos compostos com atividades antifúngicas. Objetivos: avaliar a atividade antifúngica do fármaco Cloridrato de Verapamil, determinar a Concentração Inibitória Mínima (CIM) e a Concentração Fungicida Mínima (CFM), frente à Candida albicans ATCC 18804, Candida krusei ATCC 6258, Candida parapsilosis ATCC 90018 e Candida glabrata ATCC 9030. Além de avaliar a citotoxicidade do fármaco em queratinócitos humanos (HaCaT). Metodologia: a determinação da CIM foi realizada pela técnica de microdiluição de acordo com The European Committee on Antimicrobial Susceptibility Testing (EUCAST). A CFM foi determinada por plaqueamento em ágar Sabouraud de alíquotas provenientes das diluições do ensaio de microdiluição. A avaliação da citotoxicidade foi realizada pela técnica de redução da resazurina, sendo possível avaliar a atividade mitocondrial das células HaCaT. Resultados: o fármaco Cloridrato de Verapamil demonstrou atividade antifúngica contra as quatro espécies patogênicas de Candida, com o valor de CIM de 1250 µM; valor de CFM maior que 1250 µM, sendo assim este fármaco foi considerado fungistático. Além disso, o Cloridrato de Verapamil não apresentou citotoxicidade nas concentrações avaliadas no estudo, pois, a redução de células viáveis nas concentrações mais elevadas não ultrapassa 30%. Com relação à redução de biomassa em biofilme de Candida, após tratamento com Cloridrato de Verapamil, houve redução (de 10 a 20%) para as quatro espécies de Candida em estudo, quando utilizadas concentrações de fármaco correspondentes a CIM; quando utilizadas concentrações de fármaco correspondentes a cinco vezes o valor de CIM, houve um aumento significativo na redução de biomassa (de 25% a 60%) em biofilme formado pelas quatro espécies de Candida. Conclusão: o fármaco Cloridrato de Verapamil apresentou atividade antifúngica para Candida albicans e Candida não-albicans, sendo considerado um fármaco fungistático, além de não apresentar citotoxicidade em queratinócitos humanos, e demonstrar atividade na redução de biomassa em biofilme formado pelas quatro espécies de Candida. Demais estudos são necessários para verificar a ação desse fármaco em diferentes mecanismos de virulência frente a células de Candida spp. / Abstract: The epidemiology of Candida infections has changed in recent years. Although Candida albicans is still the main pathogen causing candidiasis, recent reports have reported an increase in the incidence of infections caused by nonalbicans Candida species. The toxicity of the antifungal drugs used together with the development of resistance has become a serious clinical problem. With this, there is now an urgency in the discovery of new compounds with antifungal activities. Objectives: To evaluate the antifungal activity of the drug Verapamil Hydrochloride, to determine the Minimum Inhibitory Concentration (MIC) and the Minimum Fungicidal Concentration (CFM) against Candida albicans ATCC 18804, Candida krusei ATCC 6258, Candida parapsilosis ATCC 90018 and Candida glabrata ATCC 9030 In addition to evaluating the cytotoxicity of the drug in human keratinocytes (HaCaT). Methodology: MIC determination was performed by the microdilution technique according to The European Committee on Antimicrobial Susceptibility Testing (EUCAST). The CFM was determined by plating on Sabouraud agar from aliquots from the dilutions of the microdilution assay. The evaluation of cytotoxicity was performed using the resazurin reduction technique, and it was possible to evaluate the mitochondrial activity of HaCaT cells. Results: The drug Verapamil Hydrochloride demonstrated antifungal activity against the four pathogenic species of Candida, with MIC value of 1250 μM; CFM value greater than 1250 μM, so this drug was considered fungistatic. In addition, Verapamil Hydrochloride did not present cytotoxicity in the units evaluated in the study, because the reduction of viable cells in the most cells is not exceeded by 30%. Regarding the biomass reduction in Candida biofilm, after treatment with Verapamil Hydrochloride, there was a reduction (from 10 to 20%) for the four Candida species in study, when the use of drug corresponding to MIC; when the use of drug corresponding to 5 times of MIC, there was a significant increase in the biomass reduction (from 25% to 60%) in the biofilm molded by the four Candida species. Conclusion: Thus, the drug Verapamil Hydrochloride led to the antifungal activity of Candida albicans and non-albicans Candida species, being considered a fungicidal drug, besides not presenting cytotoxicity in human serotonizers, and were submitted to biomass reduction in biofilm molded by four Candida species. More studies are needed to verify the action of the drug on different mechanisms of virulence against Candida spp cells.
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Propriedades Bioquímicas e Funcionais de uma Proteína Ligante à Quitina Purificada de Sementes de Moringa oleifera Lamarck / Biochemical and Functional Properties of Chitin-Binding Protein Purified from seeds of Moringa oleifera Lamarck

Gifoni, Juliana Menezes January 2009 (has links)
GIFONI, Juliana Menezes. Propriedades Bioquímicas e Funcionais de uma Proteína Ligante à Quitina Purificada de Sementes de Moringa oleifera Lamarck. 2009. 140 f. Tese (Doutorado em bioquímica)- Universidade Federal do Ceará, Fortaleza-CE, 2009. / Submitted by Elineudson Ribeiro (elineudsonr@gmail.com) on 2016-07-20T16:03:34Z No. of bitstreams: 1 2009_tese_jmgifoni.pdf: 8760660 bytes, checksum: 354beec73eaacf40d4940af6fcbd173a (MD5) / Approved for entry into archive by José Jairo Viana de Sousa (jairo@ufc.br) on 2016-08-02T18:20:29Z (GMT) No. of bitstreams: 1 2009_tese_jmgifoni.pdf: 8760660 bytes, checksum: 354beec73eaacf40d4940af6fcbd173a (MD5) / Made available in DSpace on 2016-08-02T18:20:29Z (GMT). No. of bitstreams: 1 2009_tese_jmgifoni.pdf: 8760660 bytes, checksum: 354beec73eaacf40d4940af6fcbd173a (MD5) Previous issue date: 2009 / Moringa oleifera Lam. is native from Northwest India, well adapted to tropical regions. From its seeds it was isolated a new chitin binding protein, Mo-CBP3, which has coagulant properties and antifungal activity against the phytopathogen Fusarium solani. Proteins were extracted from defatted seeds flour by 0.05 M Tris-HCl buffer, pH 8.0, containing 0.15 M NaCl. The average protein content of the flour was 216.44 mgP/gF. The crude extract was fractionated in albumins and globulins by dialysis and centrifugation. Albumins were concentrated by 90% ammonium sulfate saturation. This fraction was applied into a chitin column, previously equilibrated with the same buffer. An unadsorbed and two adsorbed peaks were obtained. The first adsorbed peak was eluted with 0.1 M N-acetyl-D-glucosamine (PNAG), and the second one, with 0.05 M acetic acid, pH 3.0 (PAC). PNAG was applied into a cation exchange column, Resource S, equilibrated with 0.05 M sodium acetate buffer, pH 5.2. The third peak corresponded to Mo-CBP3 – eluted with 0.5 M NaCl in equilibrium buffer. The protein content of Mo- CBP3 was 1.17 mgP/gF. It represents a final yield of 0.54% of crude extract proteins. Apparent molecular mass by SDS-PAGE was 18.0 kDa in the absence of β-ME, and 9.0 kDa, in its presence. Results suggest that Mo-CBP3 is a dimeric protein, made of identical subunits, linked by disulfide bonds. By molecular exclusion chromatography, calculated molecular mass was 14.34 kDa, pI 10.8. Mo-CBP3 is a glycoprotein with 2.5% of carbohydrates, which has not hemagglutinating or chitinase activities. Its NH2- terminal sequence was CPAIQRCCQQLRNIQPPCRCCQ, with 22 amino acids, conffirming its basic character. Mo-CBP3 was as efficient as AlK(SO4)2 in the capacity of coagulating suspended material in water. Mo-CBP3 (0.1 mg/mL) was fungicide to Fusarium solani spores. Heat treatment of the protein at 98 °C, du ring 1 h, and pre incubation with N-acetyl-D-glucosamine, did not reverse its action. Mo-CBP3 was able to retard the mycelial growth of the fungus even at the lowest tested dose of 0.05 mg/mL. Mo-CBP3 was inactive against the oomycete Pythium oligandrum, which has cellulose in spite of chitin in cell wall. Protein was also able to inhibit about 80% of medium acidification, induced by glucose, by F. solani spores, that suggests the influence of Mo-CBP3 over the proton pumps (H+ATPases) present in cellular membranes of F. solani spores. / Moringa oleifera Lam. é uma planta originária do Noroeste da Índia, bem adaptada às regiões tropicais. De suas sementes foi isolada uma nova proteína ligante à quitina, a Mo-CBP3, com propriedades coagulantes e atividade antifúngica contra o fitopatógeno Fusarium solani. As proteínas foram extraídas da farinha delipidada de sementes com o tampão Tris-HCl 0,05 M, pH 8,0, contendo NaCl 0,15 M. O teor médio de proteína da farinha correspondeu a 216,44 mgP/gF. O extrato total foi fracionado em albuminas e globulinas por diálise contra água seguida de centrifugação. As albuminas foram concentradas com sulfato de amônio a 90% de saturação. A F0-90% foi submetida à cromatografia de afinidade em coluna de quitina, previamente equilibrada com o tampão de extração. Foram obtidos um pico não retido e dois picos retidos, correspondentes às proteínas ligantes à quitina (CBP). O primeiro destes foi eluído com solução de N-acetil-D-glucosamina 0,1 M (PNAG), e o segundo, com ácido acético 0,05 M, pH 3,0 (PAC). PNAG foi aplicado em coluna de troca catiônica, Resource S, acoplada a um sistema de FPLC, equilibrada com tampão acetato de sódio 0,05 M, pH 5,2. Dos picos obtidos, o terceiro correspondeu à proteína Mo-CBP3 - eluída com 0,5 M de NaCl no tampão de equilíbrio. O teor protéico médio calculado para a proteína purificada Mo-CBP3 foi de 1,17 mgP/gF, representando um rendimento final de 0,54% das proteínas do extrato total. A massa molecular aparente por SDS-PAGE foi de 18,0 kDa sem o agente redutor e, de 9,0 kDa, na presença deste. O resultado sugere que Mo-CBP3 seja uma proteína dimérica formada de subunidades idênticas, unidas por pontes dissulfeto. A massa molecular de Mo-CBP3, por cromatografia de exclusão molecular, foi de 14,34 kDa, e o pI de 10,8. Trata-se de uma glicoproteína com 2,5% de carboidratos, que não apresenta atividade hemaglutinante ou quitinásica. Sua seqüência NH2-Terminal obtida foi CPAIQRCCQQLRNIQPPCRCCQ, com 22 aminoácidos, confirmando sua característica básica. Mo-CBP3 mostrou-se tão eficiente quanto o AlK(SO4)2 na capacidade de coagular matéria em suspensão na água. Mo-CBP3 foi fungicida para esporos de Fusarium solani a 0,1 mg/mL. O aquecimento da proteína a 98 °C, por 1 h, e a pré-incubação com o açúcar N-acetil-D-glucosamina, não reverteram sua ação. Mo-CBP3 mostrou-se capaz de retardar o crescimento micelial do fungo ainda na menor dose testada, 0,05 mg/mL. Mo-CBP3 é inativa contra o oomiceto Pythium oligandrum, que apresenta celulose no lugar da quitina na parede celular. A proteína foi, ainda, capaz de inibir cerca de 80% da acidificação do meio, por esporos de F. solani, induzida por glicose, o que sugere a influência de Mo-CBP3 sobre as bombas de prótons (H+ATPases) presentes na membrana celular dos esporos deste fungo.
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Caracterização fenotípica e genotípica de isolados clínicos de trichophyton sp. do estado do Rio Grande do Sul

Magagnin, Cibele Massotti January 2013 (has links)
As dermatofitoses apresentam alta prevalência na população em geral, sendo Trichophyton interdigitale (Trichophyton mentagrophytes) a segunda espécie mais frequentemente relatada como causadora de infecção em humanos. O objetivo do trabalho foi determinar a identidade genética, o perfil enzimático e de assimilação de açúcares e a suscetibilidade a antifúngicos de isolados clínicos do gênero Trichopyton. Os isolados foram avaliados por de ensaios enzimáticos, assimilação de fontes de carbono e da atividade antifúngica in vitro. A caracterização genotípica foi realizada através da amplificação e do sequenciamento da região do gene que codifica a região interna do gene DNA ribossomal dos isolados testados. No estudo, todos os isolados secretaram DNase, mas nenhum deles foi capaz de secretar fosfolipase e proteinase. Por outro lado, urease e lipase foram produzidas pela maioria dos isolados testados. Entre os antifúngicos avaliados, a terbinafina e o itraconazol demonstraram melhores resultados de sensibilidade, enquanto o fluconazol apresentou baixa atividade para as amostras. A anfotericina B, apesar de menos eficaz que a terbinafina e o itraconazol, também demonstrou resultados satisfatórios. A combinação entre os antifúngicos tioconazol e terbinafina demonstrou ter atividade antagônica em todos os isolados. Todos os dermatófitos testados assimilaram inulina, sorbitol, manose, glicose e trealose. Os demais carboidratos tiveram assimilação variável entre os isolados. Genotipicamente, todos os isolados do estudo foram identificados como pertencentes à espécie T. interdigitale. Os ensaios enzimáticos e de assimilação de carboidratos apresentaram resultados variáveis entre os isolados testados, inferindo variação intraespecífica entre as amostras de T. interdigitale. O perfil de sensibilidade aos antimicóticos testados seguiu o padrão de resultados observado em estudos anteriores. A identificação genotípica através da amplificação e do sequenciamento da região ITS permitiu garantir a identidade entre os isolados testados. / The prevalence of dermatophytosis among population is high, and Trichophyton interdigitale (Trichophyton mentagrophytes) is the second most frequently reported species to cause infection in humans. This study objective was to evaluate the genetic identity, the enzymatic profile and the assimilation of carbon sources, as well as the antifungal susceptibility of clinical isolates of Trichophyton sp. The isolates were analyzed phenotypically by enzymatic assays, assimilation of carbon sources and antifungal activity in vitro. The genotypic characterization was performed by amplification and sequencing the gene region encoding the internal region of the DNA ribosomal gene of the isolates tested. In our study, all isolates secreted DNase, while none of them was capable of secreting phospholipase, keratinase and proteinase. On the other hand, lipase and urease were secreted by most of the isolates. Of the antifungal agents tested, the best results in terms of sensitivity were found with terbinafine and itraconazole, while the antifungal activity of fluconazole was found to be weak. Amphotericin B, although less effective than terbinafine and itraconazole, also yielded satisfactory results. Evaluation of the drug combination of tioconazole and terbinafine revealed an antagonistic effect for all tested isolates. All isolates assimilated inulin, sorbitol, glucose, trehalose and mannose. Arabinose, dulcitol, galactose and xylose were assimilated by some of the isolates, whereas the most isolates assimilated cellobiose, dulcitol, erytritol and mannitol. Genotypically, all isolates in the study were identified as belonging to Trichophyton interdigitale species. In general, enzyme assays and assimilation of carbohydrates showed variable results among the isolates tested, inferring intraspecific variation between Trichophyton interdigitale samples. The sensitivity profile of the antifungal agents tested in this study was similar to results obtained in previous studies. The genotypic identification, by amplification and sequencing of the ITS region, has ensured the identity of the isolates tested.

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