O milho (Zea mays) é um cereal amplamente cultivado no Brasil e no mundo. Sua produtividade pode ser afetada por diversos fatores incluindo a colonização fúngica. Em Fitopatologia, grãos afetados por fungos são denominados grãos ardidos e os gêneros mais encontrados em milho são Stenocarpella e Fusarium. Espécies de Fusarium podem causar podridões nas espigas e também podem produzir fumonisinas, toxina esta tóxica para animais e humanos e associadas ao desenvolvimento de diversas doenças. O presente trabalho teve como objetivo analisar a incidência de Fusarium ssp. com potencial toxigênico em amostras de grãos ardidos através da identificação da presença do gene fum5, responsável pela produção de fumonisinas pelo fungo, bem como quantificar os níveis de fumonisinas encontrados nessas amostras e comparação com os resultados obtidos de grãos assintomáticos. Um total de 100 amostras dos anos de 2006 e 2007 provenientes das principais regiões produtoras do Brasil foram submetidas à três análises. A primeira avaliou a incidência de Fusarium spp. nos grãos através do método do papel de filtro com congelamento e em 100% das amostras foi encontrado o fungo em níveis que variaram de 34 a 91%. A segunda análise utilizou a PCR para confirmação do gênero, identificação de espécies (F. verticillioides, F. proliferatum e F. subglutinans) e identificação da presença do gene fum5. A PCR confirmou 93% dos isolados como pertencentes ao gênero Fusarium. Os isolados negativos passaram por análise morfológica e todos foram confirmados. As PCRs para espécies identificaram 82% dos isolados como F. verticillioides, 3% como F. subglutinans e nenhum como F. proliferatum. A PCR para potencial toxigênico foi positiva para 81% dos isolados. A terceira análise consistiu na quantificação de fumonisinas (B1, B2 e B3 na proporção 5:3:1) através do método de ELISA e os níveis variaram de 4,4 a mais de 90 µg/g. Grãos assintomáticos da segunda safra de 2007 foram analisados separadamente para comparação. Em 100% das amostras houve incidência de Fusarium spp, variando de 74 a 87%. A PCR para confirmação do gênero foi positiva para 87% dos isolados e os demais passaram por análise morfológica e então confirmados. As PCRs para identificação de espécies mostrou 60% dos isolados como sendo F. verticillioides, 3% como F. subglutinans e nenhum como F. proliferatum. A maior concentração de fumonisinas nos grãos assintomáticos foi de 2,1 µg/g e em 53% das amostras não foram detectadas fumonisinas. Os resultados mostraram que há uma alta incidência de Fusarium spp. em grãos ardidos e assintomáticos. Grãos ardidos e assintomáticos têm Fusarium spp. com potencial toxigênico mas os níveis de fumonisinas encontrados nos grãos assintomáticos foram muito baixos em comparação com os encontrados nos grãos ardidos mostrando que, em condições adversas, esse fungo deixa de ser endofítico e passa a ser patogênico, podendo causar doenças na planta e produzir toxinas. Pelo fato das fumonisinas estarem concentradas nos grãos ardidos, a redução dessas toxinas da dieta deve ser baseada na eliminação dos mesmos através do controle do beneficiamento. / Maize is a cereal widely cultivated in Brazil and worldwide. Its productivity can be affected by numerous factors including fungal colonization. In pathological terms, affected grains by fungi are denominated rot grains and the two most prevalent genera found in maize are Stenocarpella and Fusarium. Species of Fusarium can cause rotting in the stalks and also produce fumonisins, which are toxic both for animals and humans since their occurrence is associated to many diseases. The present work aimed to analyse the incidence of Fusarium ssp. with toxigenic potential in rot grains samples through the identification of the presence of the gene fum5, responsible for the production of fumonisins, as well as to quantify the levels of fumonisins found in these samples and compare with the results obtained in asymptomatic grains. A total of 100 samples from the 2006 and 2007 harvests were collected from the main producing regions of Brazil and were submitted to three analyses. The first evaluated the incidence of Fusarium ssp. in the grains through the method of filter paper and freezing, which revealed incidences that varied from 34 to 91%. The second analysis used specific primers and PCR to confirm the genus and species (F. verticillioides, F. proliferatum and F. subglutinans) and to detect the presence of the fum5 gene. The results indicated that 93% of the isolates belonged to the genus Fusarium. The PCR - negative isolates were confirmed as Fusarium after morphological analysis. Eigthy two percent of the isolates were classified as F. verticillioides, 3% as F. subglutinans and none as F. proliferatum using speciesspecific PCR. The fum5 gene was detected in eighty one percent of the isolates. The third analysis consisted in the quantification of the fumonisins (B1, B2 e B3 in the proportion of 5:3:1) through the ELISA method and the levels varied from 4,4 to more than 90 µg/g. Asymptomatic grains from the second cropping season of 2007 were analyzed separately for comparison purposes. The incidence of Fusarium spp. in these varied from 74 to 87%. The PCR for confirmation of the genus was positive for 87% of the isolates. The PCRs for species identification showed 60% of the isolated as being F. verticillioides, 3% as F. subglutinans and none as F. proliferatum. The greater concentration of fumonisins in the asymptomatic grains was of 2,1 µg/g and in 53% of the samples fumonisins were not detected. Rot and asymptomatic grains presented Fusarium spp. with toxigenic potential but the levels of fumonisins found in the asymptomatic grains were much lower compared with rot grains, showing that, in adverse conditions, this fungus changes from endophytic to pathogenic, being able to parasitize the plant and to produce toxins. The fact that fumonisins levels are much higher in rot grains, a simple measure to reduce the levels of these toxins in the animal diet would be to eliminate them during processing.

O trabalho teve como objetivo avaliar a presença de fungos e aflatoxinas e ácido ciclopiazônico (ACP) em castanhas-do-brasil a campo e armazenadas, no solo e ar a fim de estabelecer vias de contaminação fúngica. A pesquisa de fungos foi feita pela técnica de semeadura em superfície em meio Ágar batata dextrose e Ágar Aspergillus flavus parasiticus e a determinação de micotoxinas, por cromatografia líquida de alta eficiência. As amostras a campo foram analisadas em: Dia 0; amostras na árvore, Dias 5, 10 e 15; em contato com solo 5, 10 e 15 dias, respectivamente. As armazenadas foram analisadas mensalmente por 11 meses. A campo, os fungos mais prevalentes foram: A. flavus em ouriços e amêndoas; Fusarium spp. em cascas. No solo foram isolados Penicillium spp. e Aspergillus flavus e no ar, Fusarium spp. e Penicillium spp. No armazenamento, em amêndoas, foi constatado A. flavus, Fusarium spp. e A. nomius; e em cascas, Fusarium spp. e A. flavus. Aflatoxinas e ACP não foram detectados. O aumento do tempo de contato das castanhas-do-brasil com o solo foi acompanhado de maior isolamento de A. flavus; sugerindo contaminação da castanha durante etapa a campo. A. nomius e A. parasiticus foram isolados apenas no armazenamento, indicando contaminação no estoque das amêndoas. / The objective of this present study was analyse, in the field and in the storage, mycobiota and the contamination by (aflatoxins and cyclopiazonic acid from Brazil nuts, soil and air samples to determine route of fungi contamination. The Brazil nuts mycobiota was determine by diluition plating method in Potate Dextrose Agar and Aspergillus flavus parasiticus agar and, micotoxins was done by high performance liquid chromatography. Field samples were collected in: day 0, samples still on the tree; days 5, 10 and 15, samples in contact with soil for 5, 10 and 15 days, respectively. The most prevalent fungi were Aspergillus flavus in fruit pods and nuts and Fusarium spp. in shells. Penicillium spp. and A. flavus were isolated from soil, and Fusarium spp. and Penicillium spp. from air. The storage samples were analysed montly during 11 months; and showed predominance A. flavus, Fusarium spp. e A. nomius in nuts, and Fusarium spp. and A. flavus in shells. Aflatoxins and cyclopiazonic acid were not detected. These findings indicate soil as the main source of fungal contamination of Brazil nuts. A. nomius e A. parasiticus were isolated only in storage, suggesting Brazil nuts contamination occurs in this period.

Certains champignons, notamment des Ascomycètes, peuvent synthétiser des métabolites secondaires toxiques pour les hommes et les vertébrés, appelés mycotoxines. Étant donné que la présence de ces champignons dans les aliments de base constitue un risque potentiel pour la santé humaine et animale, les aliments de base sont éliminés lorsqu'ils sont contaminés. La section Flavi est un des groupes de champignons les plus importants du point de vue économique et sanitaire car il comprend des espèces productrices de mycotoxines. Parmi les mycotoxines produites par ce groupe se trouvent les aflatoxines (AF), considérées comme une préoccupation majeure en raison de leurs effets délétères chez les vertébrés. Les espèces de la section Flavi se développent principalement dans les régions tropicales et subtropicales car elles bénéficient de conditions environnementales optimales. De plus, les conditions de récolte et de stockage sont souvent inappropriées, favorisant ainsi leur développement. Dans les régions tempérées, ces espèces se rencontrent moins fréquemment. Cependant, le réchauffement climatique pourrait favoriser leur colonisation. L'identification des espèces d'Aspergillus de la section Flavi est un défi, en raison de l'inter- et intra-variabilité des caractères. Par conséquent, l'utilisation d'une seule méthode d'identification (caractérisation morphologique, moléculaire ou du profil des métabolites secondaires) est insuffisante. Inversement, le développement d'outils moléculaires a facilité la tâche. Le but de notre étude était de déterminer les relations entre les espèces d'Aspergillus de la section Flavi à partir de différents marqueurs moléculaires (ITS, benA, cmdA, amdS, préA, perB, ppgA, aflP, gènes Mat1), puis d'identifier ceux qui permettent une classification des espèces par inférence phylogénétique. L'utilisation de l'inférence phylogénétique dans cette étude a montré qu'il s'agit d'une approche robuste pour identifier les espèces d'Aspergillus de la section Flavi, notamment en confirmant certaines hypothèses déjà proposées pour les espèces de la section Flavi. En effet, l'ajout de marqueurs moléculaires a permis de confirmer le placement phylogénétique des espèces dans la section Flavi. De plus, une nouvelle espèce cryptique a pu être décrite : Aspergillus korhogoensis (appartenant au clade A. flavus). Notre étude a également pu mettre en évidence que les marqueurs moléculaires sélectionnés (benA, cmdA, mcm7, rpb1, preB, preA et ppgA) sont de bons candidats pour l'étude d'autres sections d'Aspergillus. L'utilisation de l'inférence phylogénétique est une méthode élégante permettant d'identifier de façon précise les espèces. Sur la base de nos résultats, il est recommandé d'utiliser des matrices concaténées pour effectuer une inférence phylogénétique dans cette section, et la meilleure combinaison inclut les gènes benA, cmdA, et l'inclusion d'un autre gène : mcm7, rpb1, preB, preA ou ppgA. A l'inverse, l'utilisation du gène ITS chez Aspergillus peut conduire à une sous-estimation de la diversité car le gène est très fortement conservé. L'étude des gènes du loci Mat1 dans la section est utile pour accroître les connaissances sur la reproduction sexuée chez les ascomycètes. De plus, plusieurs fonctions de la machinerie biologique fongique sont liées aux gènes du loci Mat1. La caractérisation du profil métabolique secondaire chez les souches d'Aspergillus de la section Flavi doit être utilisée, non seulement comme outil d'identification, mais également pour discriminer les souches toxinogènes et atoxinogènes. La section Flavi renferme des espèces capables de produire à la fois de mycotoxines et de composés bénéfiques. Parmi les mycotoxines qui devraient faire l'objet d'une attention particulière figurent les AF, l'acide cyclopiazonique, les versicolorines a et b, la stérigmatocystine. Une étude plus approfondie du métabolisme secondaire sera également utile pour la recherche de nouveaux composés bénéfiques. / Some fungi, mostly Ascomycota, are able to synthesize secondary metabolites that are toxic to humans and vertebrates, called mycotoxins. Since the presence of these fungi in staples represents a potential risk to human and livestock health, staples are eliminated when they are contaminated. The section Flavi is one most important group of fungi from an economic and public health point of view because it comprises several mycotoxin producer species. Amongst the mycotoxins produced by this group are aflatoxins (AFs), considered a main concern because of their deleterious effects on humans and vertebrates. Species from section Flavi grow mainly in tropical and subtropical regions where environmental conditions are optimal, and harvest and storage conditions are not always appropriate to avoid production of mycotoxins, which enhance their growth. In temperate regions, these species are less frequent; however, climate changes can favor their colonization. Species identification in Aspergillus section Flavi is challenging because of inter- and intra- variability of traits. Therefore, the use of one identification method (morphological, molecular or secondary metabolite profile characterization) is futile. Conversely, the development of molecular tools has facilitated the task. The aim of this study was to screen the species relationships in Aspergillus section Flavi based on different molecular markers (ITS, benA, cmdA, amdS, preA, preB, ppgA, aflP, Mat1 genes), and subsequently identify which ones allow a fine species classification in the section Flavi by phylogenetic inference. The use of phylogenetic inference in the present study showed that it is a robust approach to identify Aspergillus section Flavi species. The use of this technique confirmed some of the hypotheses proposed in the Flavi section, since more genetic information was added, thus strengthening the placement of the species in the Flavi section. In addition, we described a new cryptic species in this section Aspergillus korhogoensis that is nested in A. flavus clade as the sister taxon of A. parvisclerotigenus. Likewise, the molecular markers (benA, cmdA, mcm7, rpb1, preB, preA or ppgA) were good candidates for studying other sections in Aspergillus. The use of phylogenetic inference is a good method for fine-scale species identification; however, it should be used carefully, and the morphological approach and characterization of secondary metabolites should also be carried out. Based on our results, concatenated matrices are recommended to perform phylogenetic inference in this section, and the best combination includes benA, cmdA, and the inclusion of at least one another gene (preB, mcm7, rpb1, preA or ppgA). Conversely, the use of ITS in Aspergillus may lead to an underestimation of the diversity because the gene is highly conserved. Studying mating type MAT1 loci in the section is helpful to increase the knowledge of sexual reproduction in ascomycetes. In addition, several functions of fungal biological machinery are linked to Mat1 loci genes. Secondary metabolic profile characterization of Aspergillus section Flavi strains should be performed, not only as an identification tool, but also to discriminate toxinogenic and atoxinogenic strains. Section Flavi encloses species able to produce a mixture of mycotoxins and beneficial compounds. Amongst mycotoxins that should be screened are AFs, cyclopiazonic acid, A and B versicolorin, sterigmatocystin, tenuazonic acid. An exhaustive study of the secondary metabolism can also be useful to investigate novel beneficial products.

Phytopathogene <i>Fusarium</i> spp.treten weltweit in landwirtschaftlichen Kulturen auf und führen häufig zur Ertragsreduktion, Verschlechterung der Produktqualität sowie Kontaminationen der Erntegüter mit toxischen Sekundärmetaboliten, sog. Mykotoxinen. Die durch <i>Fusarium spp.</i> hervorgerufene partielle Taubährigkeit (FHB) des Weizens und anderer Getreidearten sowie die <i>Fusarium</i> Kolbenfäule an Mais sind aus ökonomischer Sicht von besonderer Bedeutung. Im Rahmen dieser Arbeit wurde die Verwendung von volatilen organischen Verbindungen (VOCs) zur Detektion von Fusariosen an Sommerweizen und Hybridmais unter Gewächshausbedingungen untersucht. Maiskolben wurden mit <i>F. graminearum</i>, <i>F. verticillioides</i> und <i>F. subglutinans</i> infiziert, während Weizenähren mit Sporensuspensionen von <i>F. graminearum</i>, <i>F. avenaceum</i> und <i>F. poae</i> inokuliert wurden. Auch Mischinfektionen wurden durchgeführt. Für die Sammlung der VOCs wurde ein statisches Verfahren (Festphasenmikroextraktion, SPME) sowie ein dynamisches Verfahren (open-loop stripping, OLS) eingesetzt. Die Analyse erfolgte in beiden Fällen mittels GC-MS. Ein nichtparametrischer Test (Kruskal-Wallis) wurde zur Identifikation von spezifischen volatilen Markern herangezogen. Auf diese Weise konnte an Mais ein Set aus 27 volatilen Biomarkern für die Infektion mit <i>Fusarium</i> spp. ermittelt werden. Die Kombination der VOCs ermöglichte hier die Unterscheidung zwischen Infektionen mit <i>F. graminearum</i> und <i>F. verticillioides</i>. An Weizen konnte ein Set aus 13 charakteristischen VOCs für den <i>Fusarium</i> Befall ermittelt werden. Die selektierten volatilen Marker beinhalteten sowohl einfache Moleküle mit 5 bis 8 Kohlenstoffatomen (C₅ - C₈), welche häufig von Pflanzen und Mikroorganismen emittiert werden, als auch infektionsspezifische Sesquiterpene (C₁₅H₂₄). In Zeitreihenversuchen konnte gezeigt werden, dass ein Großteil der relevanten VOCs bereits nach kurzer Zeit emittiert wird. So waren in Mais volatile Biomarker detektierbar, bevor Symptome am Kolben erkennbar waren (4 – 8 Tage nach der Inokulation). Ein Monitoring von VOC Profilen im Hinblick auf volatile Marker könnte eine schnelle und nicht-destruktive Detektion von <i>Fusarium</i> Infektionen (ggf. auch Risikoabschätzung zur Mykotoxinbelastung), z.B. im Feld oder Lager, ermöglichen. Hierfür stehen transportable Detektoren zur Verfügung. Das makrozyklische Lacton Zearalenon (ZEN) wird von mehreren <i>Fusarium</i> spp. produziert und besitzt eine östrogene Wirkung auf den menschlichen und tierischen Organismus. Schweine gelten diesbezüglich als besonders anfällig. ZEN wird in gemäßigten Klimazonen regelmäßig in Lebens- und Futtermitteln nachgewiesen. Bislang wurden zahlreiche Bioassays für die Detektion von ZEN beschrieben. Sie basieren meist auf den menschlichen Östrogenrezeptoren α und β und reagieren unspezifisch auf eine Vielzahl von östrogenen Substanzen (z.B. Genistein, 17β-Estradiol). Die vorliegende Arbeit beschreibt erstmalig ein Bioassay zur spezifischen Detektion von ZEN sowie dem kritischen Metabolit α-Zearalenol (α-ZOL). Das Assay basiert auf einer <i>zes2::gfp</i> Mutante des Mykoparasiten <i>Gliocladium roseum</i> und ermöglicht eine Detektion von ZEN in Feldproben (z.B. kontaminierter Mais). Schritte zur Probenvorbereitung und Extraktion, einschließlich Aufreinigung mit Immunoaffinitätssäulen, sowie die Kultur des Inditaktorstammes wurden optimiert. Das Assay eignet sich für die qualitative Detektion von ZEN in einem weiten Konzentrationsbereich sowie für eine quantitative ZEN Bestimmung in kontaminierten Mais Feldproben im Bereich zwischen 0,9 mg kg^-1 und 90 mg kg^-1. Neben der Detektion in Feldproben, konnte das Bioassay erfolgreich für ein Screening von Pilzstämmen zur Identifikation von ZEN-Produzenten eingesetzt werden. Das hier beschriebene <i>G. roseum zes2::gfp</i> Bioassay kann mit einer einfachen Laborausstattung durchgeführt werden und eignet sich möglicherweise für die Anwendung in Entwicklungsländern.

Thesis (D.Tech.: Clinical Technology)-Durban Institute of Technology, 2005 xxiv, 235 leaves ; ill. ; 30 cm / Fumonisin B1 (FB1) and ochratoxin A (OTA) represent examples of mycotoxins of greatest public health and agro-economic significance. They ex¬ert adverse effects on humans, animals and crops that result in illnesses and economic losses. Fumonisin B1 are cancer-promoting metabo¬lites of Fusarium proliferatum and F verticillioides, (formerly moniliforme), and are implicated in oesophageal cancer. Ochratoxins are metabolites of both Aspergillus and Penicillium species. These compounds are known for their nephrotoxic effects in all animal species and may promote tumours in humans. In man OTA exhibits unusual toxicokinetics, with a half-life in blood of 840 h (35 days) after oral ingestion. Although much is known regarding the toxicology of these toxins, little is known of the effects of these toxins on the immune system. The aim of this study was to determine and compare the immunomodulating effects of FB1 and OTA in human carcinoma. Initial experiments involved isolating lymphocytes and neutrophils from healthy volunteers. The isolated cells were exposed to either FB1 or OTA on a dose and time dependent level and LD50 of the toxins was determined. Thereafter, challenge tests were performed, whereby lymphocytes and neutrophils isolated from volunteers, oesophageal cancer patients and breast cancer patients were exposed to the LD50 dose of either FB1 or OTA for the appropriate time. The effect of the toxins was demonstrated by viability studies, light microscopy and electron microscopy. Cytokine receptors (CK, TNF and CSF) were evaluated by immuno-cytochemical methods and the levels of circulating cytokines (IL –1, IL-6, IL-8, IL-10 and TNF-) were determined using ELISA kits.

Thesis (M.Tech.: Biotechnology)- Dept. of Biotechnology & Food Technology, Durban University of Technology, 2007 xv, 102 leaves / For decades the genus Aspergillus (of fungi) has been classified based on morphological and growth criteria. Members of the Aspergillus section Flavi are economically valuable and methods of differentiating them are thus very important. Several molecular methods have been developed to distinguish these strains. Also, a number of biochemical and genetic studies have been used in order to provide a better means of classification (Lee et al., 2004). Aflatoxins, the most frequently studied mycotoxins, are produced by certain Aspergillus species/strains/isolates of fungi. The aflatoxin biosynthetic pathway studies have led to a number of discoveries. Several structural and regulatory genes (and their enzymes) involved in the biosynthesis of aflatoxins have been discovered and purified (Trail et al., 1995). Aflatoxin production and contamination of agricultural crops are major causes of economic losses in agriculture. Thus, better methods of characterization/differentiation are required for both aflatoxigenic and non-aflatoxigenic isolates. Molecular biology is one of the current tools used to differentiate between these isolates. Polymerase Chain Reaction (PCR)-based randomly amplified polymorphic DNA (RAPD) analysis has been used successfully in the analysis of DNA relatedness of species of fungi, bacteria, plants and animals. Dendograms which evaluate/assess the likeness between different isolates has also been used (Martinez et al., 2001). Restriction fragment length polymorphism (RFLP) analysis has been applied to a number of studies to detect differences between fungi and to establish relationships between them. Therefore, the scope of this study was to investigate RAPD analysis (with dendograms) and detection of RFLPs by hybridization as molecular methods that can distinctly differentiate or characterize the aflatoxigenic and non-aflatoxigenic Aspergillus isolates.

In this thesis, it is shown how aflatoxins can be determined in biological material. The thesis is a summary of five papers. Aflatoxins are carcinogenic mycotoxins produced by Aspergillus moulds. Methods were developed for the determination of aflatoxins in samples of airborne dust and human urine collected at feed factories. For the dust samples from such agricultural products as copra, cotton seed and maize, methods were developed for the determination of aflatoxins B1, B2, G1 and G2. For urine samples, methods were developed for analysing the four aflatoxins above that naturally occur in dust, and the metabolites aflatoxins M1 and Q1. Sample preparation of dust samples included solvent extraction, filtration and immunoaffinity column extraction. Urine samples were cleaned up using immunoaffinity column extraction or solid-phase extraction using ethyl bonded-phase columns. All extractions with these columns were automated by means of a laboratory robot. Reversed-phase liquid chromatography was used to separate the aflatoxins in the cleaned-up extracts. Detection was performed by fluorescence after post-column derivatization by addition of bromine. Parameters for the derivatization were studied using factorial designs. To confirm the identity of aflatoxins in naturally contaminated airborne dust samples and spiked urine, liquid chromatography was combined with electrospray mass spectrometry. The detection limits of the aflatoxins in dust samples were in the range 1.8-3.1 ng/g in 10-mg dust samples using fluorescence detection. Aflatoxins were determined in spiked urine down to the 6.8-18 pg/ml level. In naturally contaminated dust of copra and cotton seed, aflatoxins were detected with a content of 9-50 pg/mg of aflatoxin Bi. No aflatoxins could be detected in any urine sample obtained from feed factory workers that were less than 6.8 pg/ml of aflatoxins B1, B2, G1 and G2 and less than 18 pg/ml of aflatoxins M1 and Q1. / <p>Diss. (sammanfattning) Umeå : Univ., härtill 5 uppsatser</p> / digitalisering@umu

Siekiant pagerinti silosuojamų pašarų kokybę ir užtikrinti galvijų sveikatingumą, buvo ištirtas kukurūzų siloso užterštumas, siloso mėginiai paimti iš įvairių Lietuvos vietovių ir įvertintas užterštumas mikroormanizmais ir mikromicetais. Nustatytas mikromicetų jautrumas Vaistinio čiobrelio (Thymus vulgaris), Vaistinio šalavijo (Salvia officinalis) ir Paprastojo raudonėlio ( Origanum vulgare) 100% eteriniams aliejams. Užkonservavus kukurūzų siloso žaliavą laboratorinėmis sąlygomis, po 96 dienų buvo nustatytas eterinių aliejų antigrybinis ir antibakterinis veikimas minėtiems eterininiams aliejams 1:100, 1:200 koncentracijų, Vaistinio čiobrelio ir Vaistinės juozažolės, ekstraktams ir žolelėms. Nustatytos trichotecenų (T–2), deoksinivalenolo (DON), zearalenono (ZON) ir aflatoksino B1 (AFL B1), mikotoksinų koncentracijos Vaistinio čiobrelio, Vaistinės juozažolės, Vaistinio šalavijo ir Paprastojo raudonėlio eterinių aliejų 1:200 koncentracijojose. / In order to assess contamination of corn silage, it´s examples were taken from diffrent locations of Lithuania and established their contamination of microorganisms. Established the sensitivity of fungi for Thyme (Thymus vulgaris), Hyssop (Hyssopus officinalis) ), Salvia (Salvia officinalis), and Oregano (Origanum vulgare), 100% essential oils. In fermented raw corn silage on laboratory conditions after 96 days were established antibacterial and antifungal activity of essential oils in 1:100 and 1:200 concentations, Thyme and Hyssop extraxts and herbs.In mentioned essential ois 1:200 concentrations were established T–2 toksinas, deoxynivalenol ( DON) , zearalenone ( ZON ) and aflatoxin B1 ( AFL B1) mycotoxins concentrations.

Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 1998. / "A thesis presented to the University of Western Sydney for the degree of Doctor of Philosophy, September, 1998" Bibliography: leaves 193 - 219.

Thesis (D.Tech.: Clinical Technology)-Durban Institute of Technology, 2005 xxiv, 235 leaves ; ill. ; 30 cm / Fumonisin B1 (FB1) and ochratoxin A (OTA) represent examples of mycotoxins of greatest public health and agro-economic significance. They ex¬ert adverse effects on humans, animals and crops that result in illnesses and economic losses. Fumonisin B1 are cancer-promoting metabo¬lites of Fusarium proliferatum and F verticillioides, (formerly moniliforme), and are implicated in oesophageal cancer. Ochratoxins are metabolites of both Aspergillus and Penicillium species. These compounds are known for their nephrotoxic effects in all animal species and may promote tumours in humans. In man OTA exhibits unusual toxicokinetics, with a half-life in blood of 840 h (35 days) after oral ingestion. Although much is known regarding the toxicology of these toxins, little is known of the effects of these toxins on the immune system. The aim of this study was to determine and compare the immunomodulating effects of FB1 and OTA in human carcinoma. Initial experiments involved isolating lymphocytes and neutrophils from healthy volunteers. The isolated cells were exposed to either FB1 or OTA on a dose and time dependent level and LD50 of the toxins was determined. Thereafter, challenge tests were performed, whereby lymphocytes and neutrophils isolated from volunteers, oesophageal cancer patients and breast cancer patients were exposed to the LD50 dose of either FB1 or OTA for the appropriate time. The effect of the toxins was demonstrated by viability studies, light microscopy and electron microscopy. Cytokine receptors (CK, TNF and CSF) were evaluated by immuno-cytochemical methods and the levels of circulating cytokines (IL –1, IL-6, IL-8, IL-10 and TNF-) were determined using ELISA kits.