Symptoms of Fusarium graminearum infection in irrigated rice grains / Sintomas de infecção por Fusarium graminearum em grãos de arroz irrigado

The fungus Fusarium graminearum was one of the first pathogens described as causing infections in rice; however, in Brazil, there is no description of its occurrence in panicles. The present study aimed to describe the symptoms caused by F. graminearum infection in irrigated rice grains. The experiment was conducted in a greenhouse in duplicate using the irrigated rice cultivar SCS 121CL and hybrid INOV CL at the R4 (flowering) stage. Two isolate of Fusarium graminearium species complex 15A (F. graminearium - 15-ADON) and FmNiv (F. meridionale - Nivalenol), was inoculated onto panicles by spraying with macroconidia and the development of symptoms was monitored until harvest. There was no difference in symptoms among isolates. Light brown spots were observed in the glumes three days after inoculation. These later evolved into brown lesions of irregular shape and size. The glume darkened to purple when the grains were in the filling stage (R6). On maturation, the glume showed dark brown coloration. Severely infected grains were shriveled and brittle.(AU)

O fungo Fusarium graminearum foi um dos primeiros patógenos descritos na cultura do arroz, no entanto, no Brasil, não há descrição de sua ocorrência em panículas. O objetivo desse estudo foi descrever os sintomas ocasionados pela infecção de F. graminearum em grãos de arroz irrigado. O experimento foi conduzido, em casa de vegetação, duas vezes, com a cultivar de arroz irrigado SCS 121CL e o Híbrido INOV CL no estádio R4 (florescimento). Dois isolados de espécies do complexo Fusarium graminearium, 15A (F. graminearium - 15ADON) e FmNiv (F, meridionale - Nivalenol) foram inoculados em panículas por aspersão de macroconídios, com acompanhamento da evolução dos sintomas até a colheita. Não houve diferença entre os isolados. Pontos de coloração parda foram observados nas glumas três dias após inoculação, evoluindo, posteriormente, para lesões de coloração marrom-claro de tamanho e forma irregular. Houve escurecimento total da gluma com coloração arroxeada quando os grãos encontravam-se no estádio de enchimento de grão (R6). Na maturação de colheita a gluma dos grãos apresentava coloração marrom-escuro. Grãos severamente infectados mostraram-se chochos e quebradiços.(AU)

Simultaneous determination of mycotoxins in peruvian purple maize / Determinação simultânea de micotoxinas em milho roxo peruano

Purple maize is an important foodstuff for the Peruvian people. Its unique nutritional and antioxidant characteristics makes it widely exported to other countries. However, when contaminated by fungi, it can trigger numerous health problems in the consumers. This study aimed to evaluate the presence of 27 mycotoxins in 63 samples of purple maize collected in Peru. Frequency of occurrence and mean concentration of the following mycotoxins were determined: alternariolmetileter (AME), alternariol (AOH), tentoxin, neosolaniol, nivalenol, wortmannin, deoxynivalenol, 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, zearalenone, aflatoxin B1, aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, fumonisin B3, ochratoxin A, ochratoxin , T-2 toxin, HT-2 toxin, fusarenon x, cyclopiazonic acid, gliotoxin, agroclavin and citreoviridin. The main mycotoxins reported in purple maize were AME and AOH, with a frequency of occurrence of 14.3 and 7.9%, and mean concentration of 23.3% and 1.8%, respectively. AME and AOH do not have guidance levels in the Brazilian legislation. Contrastingly, levels of mycotoxins which are within the standards of the countrys regulations were below the limit of quantification. The present results suggested that purple maize is a raw material with a great potential for the production and industrialization of special products.(AU)

O milho roxo é um alimento importante para o povo peruano. Suas características nutricionais e antioxidantes únicas fazem com que seja amplamente exportado para outros países. No entanto, quando contaminado por fungos, pode desencadear inúmeros problemas de saúde nos consumidores. Este estudo teve como objetivo avaliar a presença de 27 micotoxinas em 63 amostras de milho roxo coletadas no Peru. A frequência de ocorrência e a concentração média das seguintes micotoxinas foram determinadas: alternariolmetileter (AME), alternariol (AOH), tentoxina, neosolaniol, nivalenol, wortmanina, desoxinivalenol, 3-acetil desoxinivalenol, 15-acetil desoxinivalenol, zearalenona, aflatoxina B1, aflatoxina B2 , aflatoxina G1, aflatoxina G2, fumonisina B1, fumonisina B2, fumonisina B3, ocratoxina A, ocratoxina, toxina T-2, toxina HT-2, fusarenona x, ácido ciclopiazonico, gliotoxina, agroclavina e citreoviridina. As principais micotoxinas encontradas no milho roxo foram AME e AOH, com frequência de ocorrência de 14,3% e 7,9% e concentração média de 23,3% e 1,8%, respectivamente. AME e AOH não possuem níveis de orientação na legislação brasileira. Contrastantemente, os níveis de micotoxinas que estão dentro dos padrões das regulamentações do país estavam abaixo do limite de quantificação. Os presentes resultados sugerem que o milho roxo é uma matéria-prima com grande potencial para a produção e industrialização de produtos especiais.(AU)

Common resistance to Fusarium head blight in Brazilian wheat cultivars

Mycotoxin levels in Fusarium head blight (FHB) infections can be difficult to quantify. The relationship between mycotoxin and disease is not consistent and it is not clear if wheat-pathogen interaction is of significance in regions where more than one Fusarium species with dis-tinct trichothecene production ability co-exists. This study aimed to investigate whether a set of eight Brazilian wheat genotypes, varying in resistance according to classification by the breeder, exhibit a common or differential resistance to Fusarium graminearum (Fgra) (deoxynivalenol-producing) and Fusarium meridionale (nivalenol-producing) (Fmer) using full-spike and central spikelet inoculation (type II resistance). Fgra was generally more aggressive than Fmer based on the percentage of diseased spikes (99 and 84 %, respectively) and number of diseased spikelets (mean 2.8 and 2.0, respectively) below the central spikelet. The genotype-pathogen species interaction was not significant, but there were differences between the genotypes, with BRS 194 and BRS 327 being the least and most resistant, respectively, based on severity ratings. The incidence of Fusarium-damaged kernel (FDK, %) was not affected by species, but two genotypes (BRS Parrudo and BRS 327) showed a lower incidence of FDK. There were substantial variations in the accumulation of deoxynivalenol and nivalenol among the genotypes, reaching maxima of 691.2 μg g–1 and 355.2 μg g–1, respectively, suggesting that Fgra is a more potent producer of trichothecene. Our data confirm prior resistance classifications by the breeders and suggest that the use of a single highly aggressive Fgra isolate may be sufficient for effective screening for FHB resistance. However, further studies are needed to elucidate the accumulation of resistance to trichothecene.

Common resistance to Fusarium head blight in Brazilian wheat cultivars

Mycotoxin levels in Fusarium head blight (FHB) infections can be difficult to quantify. The relationship between mycotoxin and disease is not consistent and it is not clear if wheat-pathogen interaction is of significance in regions where more than one Fusarium species with dis-tinct trichothecene production ability co-exists. This study aimed to investigate whether a set of eight Brazilian wheat genotypes, varying in resistance according to classification by the breeder, exhibit a common or differential resistance to Fusarium graminearum (Fgra) (deoxynivalenol-producing) and Fusarium meridionale (nivalenol-producing) (Fmer) using full-spike and central spikelet inoculation (type II resistance). Fgra was generally more aggressive than Fmer based on the percentage of diseased spikes (99 and 84 %, respectively) and number of diseased spikelets (mean 2.8 and 2.0, respectively) below the central spikelet. The genotype-pathogen species interaction was not significant, but there were differences between the genotypes, with BRS 194 and BRS 327 being the least and most resistant, respectively, based on severity ratings. The incidence of Fusarium-damaged kernel (FDK, %) was not affected by species, but two genotypes (BRS Parrudo and BRS 327) showed a lower incidence of FDK. There were substantial variations in the accumulation of deoxynivalenol and nivalenol among the genotypes, reaching maxima of 691.2 μg g–1 and 355.2 μg g–1, respectively, suggesting that Fgra is a more potent producer of trichothecene. Our data confirm prior resistance classifications by the breeders and suggest that the use of a single highly aggressive Fgra isolate may be sufficient for effective screening for FHB resistance. However, further studies are needed to elucidate the accumulation of resistance to trichothecene.(AU)

Determinação simultânea de micotoxinas em cereais.

Micotoxinas são metabólitos secundários produzidos por fungos filamentosos que podem estar presentes em inúmeros alimentos consumidos mundialmente. Quando alimentos contaminados são ingeridos por humanos ou animais podem ser considerados tóxicos. Diante disso, o objetivo do estudo foi aplicar um método quantitativo para as micotoxinas com e sem legislação vigente presentes em amostras de trigo e aveia em 2016 e 2017 e milho roxo em 2017. Foram analisadas 465 amostras, sendo 91 de aveia e 374 de trigo provenientes dos estados de Santa Catarina e Rio Grande do Sul e 63 amostras de milho roxo provenientes do Peru. Determinou-se a frequência de ocorrência e a concentração das micotoxinas alternariol (AOH), alternariolmetileter (AME), tentoxina, neosolaniol, nivalenol (NIV), vortmanina, 3-acetil deoxinivalenol, 15-acetil deoxinivalenol, deoxinivalenol (DON), zearalenona (ZEA), aflatoxina B1 (AB1), aflatoxina B2, aflatoxina G1, aflatoxina G2, fumonisina B1, fumonisina B2, fumonisina B3, ocratoxina A, ocratoxina , toxina T2, toxina HT2, diacetoxiscirpenol, fusarenon-x, ácido ciclopiazônico, gliotoxina, agroclavina e citroviridina. Foram encontrados níveis médios de micotoxinas dentro dos padrões da legislação brasileira, porém alguns metabólitos detectados não apresentam especificações para os cereais estudados. As principais micotoxinas encontradas em aveia foram AME e AOH, com frequência de ocorrência de 100 e 98%, respectivamente. As mesmas micotoxinas foram as principais encontradas em trigo,, seguidas de NIV, DON, ZEA e AB1, dependendo do ano de coleta das amostras. No milho roxo não foram encontrados micotoxinas presentes na legislação brasileira. Todas as micotoxinas presentes na legislação apresentaram níveis abaixo do limite de quantificação. As principais micotoxinas encontradas em milho roxo foram AME e AOH, com frequência de ocorrência de 14,3 e 7,9%, respectivamente. Para as amostras de trigo e aveia conclui-se que em ambos os anos e cereais foram detectadas micotoxinas não incluídas na legislação, e alerta-se para a contaminação por micotoxinas que estão regulamentadas, em alguns casos acima dos níveis permitidos. A metodologia utilizada para determinação das micotoxinas foi cromatografia liquida de alta eficiência acoplada a espectrometria de massas. Esta é a primeira pesquisa de micotoxinas emergentes em aveia, trigo e milho roxo.

Mycotoxins are secondary metabolites produced by filamentous fungi present in oat and wheat and several foodstuffs consumed worldwide. When contaminated food items are ingested, they may be toxic to humans and animals. Thus, this study aimed to apply a qualitative screening method and quantify the mycotoxins with and without current legislation present in oat and wheat samples in 2016 and 2017 and in purple maize in 2017. Four hundred and sixty-five samples of oat (91) and wheat (374) from the states of Rio Grande do Sul and Santa Catarina states and 63 samples of Peuvian purple maize from Peru were analyzed. The frequency of occurrence and concentration of the following mycotoxins were determined: alternariolmetileter (AME), alternariol (AOH), tentoxin, neosolaniol, nivalenol (NIV), wortmannin, deoxynivalenol (DON), 3-acetyl deoxynivalenol, 15-acetyl deoxynivalenol, zearalenone (ZEA), aflatoxin B1 (AFB1), aflatoxin B2, aflatoxin G1, aflatoxin G2, fumonisin B1, fumonisin B2, fumonisin B3, ochratoxin A, ochratoxin , T-2 toxin, HT-2 toxin, fusarenon x, cyclopiazonic acid, gliotoxin, agroclavin and citreoviridin. Mean levels of mycotoxins within the standards of the Brazilian legislation were found, but some of the detected metabolites do not present specifications for the studied cereals. The main mycotoxins detected in oat were AME and AOH, with a frequency of occurrence of 100 and 98%, respectively. These were also the main mycotoxins found in wheat, followed by NIV, DON, ZEA and AFB1, depending on the year of sample collection. For purple maize no mycotoxins were found in the Brazilian legislation. All mycotoxins present in the legislation had levels below the limit of quantification. The main mycotoxins found in purple maize were also AME and AOH, with frequency of occurrence of 14.3 and 7.9%, respectively It may be concluded that mycotoxins without guidance levels were detected in both cereals and years. Moreover, a warning must be made regarding the contamination at high concentrations by mycotoxins which are regulated, in some cases exceeding the permitted levels. For wheat and oatmeal samples, it may be concluded that in both years and cereals mycotoxins not included in the legislation were detected, and a warning must be made for the contamination by mycotoxins that are regulated, in some cases above the permitted levels. This is the first survey to analyze emerging mycotoxins in oats, wheat and purple corn.

Toxigenic potential of Fusarium graminearum isolated from maize of northwest Argentina

Twenty six isolates of Fusarium graminearum from grains of maize hybrids harvested in ±west Argentina were grown on autoclaved rice grain to assess their ability to produce type B trichothecenes. Chemical analysis indicated that 38% of isolates were nivalenol (NIV) producers only, 31% were major NIV producers with high DON(deoxynivalenol)/NIV ratios, 8% were major DON producers with minor NIV production, and 23% were DON producers only. Isolates showed a high variability in their toxigenic potential which was not related to fungal biomass. The distribution of the different chemotypes as well as the high and the low trichothecene-producing Fusarium isolates could not be associated to a geographical origin. Our results confirmed for the first time that isolates of Fusarium graminearum from maize of northwest Argentina are able to produce DON and NIV. A substancial contamination with both NIV and DON is likely in maize from northwest Argentina. Their contents should be quantified in regional surveillances for mycotoxin contamination.(AU)

Incidence and multiplex PCR based detection of trichothecene chemotypes of Fusarium culmorum isolates collected from freshly harvested Maize kernels in Southern India

Hundred Fusarium culmorum strains, isolated from freshly harvested maize grain samples from Southern parts of India, were incubated in czapek-dox medium and analyzed for trichothecene (DON/NIV) production. The mPCR assay was standardized targeting trichothecene metabolic pathway genes viz., Tri6, Tri7, Tri13 for detection of trichothecene (DON/NIV) chemotypes and rDNA gene for specific detection of F. culmorum species. Primers for targeted genes were designed and used to predict whether these isolates could produce deoxynivalenol/nivalenol, 94 isolates were able to produce DON/NIV by mPCR assay. Chemical analysis of DON/NIV was carried out for mPCR positive isolates by high performance-thin layer chromatography (HPTLC). To check the practical usefulness of developed mPCR assay, 150 field samples of maize were evaluated and results were compared with conventional HPTLC method. Out of 150 samples, 34% samples stayed as a positive for NIV contamination whereas 44% were found to have deoxynivalenol contamination. Moreover, mPCR results are equivocally matched with the HPTLC chemical analysis for field samples. Chemotyping of F. culmorum isolates were reported for the first time from India, and highlights the important potential of F. culmorum to contaminate maize with DON/NIV.(AU)

Micotoxinas no milho roxo peruano.

O milho roxo é uma variedade de milho que é produzido nos Andes peruanos. Sua cor característica é pela presença do pigmento antiocianina que apresenta propriedades antioxidantes, antimutagênicas, anticancerígenas e antidiabéticas. Estas características fizeram com que além de ser usado como corante, seja utilizado como matéria prima na elaboração de vários subprodutos. Atualmente o Peru exporta este insumo, porém, pela falta de regulamentação e por ser considerado um produto orgânico, não são exigidas análises de micotoxinas. Estas toxinas, podem ser produzidas por fungos filamentosos em qualquer etapa da cadeia alimentícia do milho. O seu consumo por humanos ou animais pode provocar efeitos carcinogênicos, mutagênicos, hepatotóxicos, estrogênicos, imunotóxicos e nefrotóxicos, motivo pelo qual órgãos internacionais determinaram limites máximos toleráveis (LMT) de micotoxinas em alimentos para tentar controlar a exposição. Considerando os possíveis efeitos que as micotoxinas podem ocasionar nos consumidores de milho roxo peruano, objetivou-se determinar a presença de micotoxinas neste milho através da identificação e quantificação por LC-MS/MS. 82 amostras de milho roxo foram obtidas em diferentes mercados do Peru em dois períodos: dezembro de 2015 a março de 2016 e março a abril de 2017. As micotoxinas analisadas foram as aflatoxinas, fumonisinas, zearelenona, ocratoxina A e os seguintes tricotecenos: deoxinivalenol, nivalenol, fusarenona X, deacetoxiscirpenol, 3 acetil-DON, toxina HT-2 e toxina T-2. As micotoxinas com maior frequência foram aflatoxinas e fumonisinas, 64,6 e 63,4%, respectivamente, com co-ocorrência destas duas micotoxinas em 45,1% das amostras. Somente em uma amostra foi quantificado zearalenona (24,4 µg/kg), enquanto que a ausência de ocratoxina A e tricotecenos foi verificado. Considerando os LMT, implementados pela Comunidade Europeia (EC, 2006; 2007; 2013), 12% das amostras analisadas apresentaram concentrações superiores ao LMT de 1000 µg kg-1 para fumonisinas e uma amostra apresentou LMT de 10 µg kg-1 superior para aflatoxinas. No entanto, considerando a legislação brasileira, 9,8% das amostras apresentaram níveis superiores ao LMT de 5000 µg/kg de fumonisinas (BRASIL, 2011; 2013; 2017). Esta é a primeira pesquisa que avalia a ocorrência de micotoxinas no milho roxo peruano e identifica que esse milho pode constituir uma fonte de intoxicação, oferecendo risco à saúde pública. A cadeia produtiva deste grau precisa de controles para determinar os fatores que influenciam na apresentação de micotoxinas e implementar uma legislação com os LMT de micotoxinas neste produto.

Purple corn is a variety of corn that is produced in the Peruvian Andes. Its characteristic color is by the presence of the pigment called antiocyanine that presents antioxidant, antimutagenic, anticancer and anti-diabetic properties. These characteristics have made that in addition to being used as a dye, is used as raw material in the elaboration of several by-products. Currently Peru exports this input, however, due to the lack of regulation and because it is considered an organic product, mycotoxin analyzes are not required. These toxins can be produced by filamentous fungi at any stage of the maize food chain. Its consumption by humans or animals can cause carcinogenic, mutagenic, hepatotoxic, estrogenic, immunotoxic and nephrotoxic effects, which is why international organisms have established maximum tolerable limits (MTL) of mycotoxins in foods to try to control exposure. Considering the possible effects of mycotoxins on consumers of Peruvian purple maize, the objective was to determine the presence of mycotoxins in this corn through LC-MS/MS. A total of 82 samples of purple maize were obtained from different Peruvian markets in two periods: December 2015 to March 2016 and March to April 2017. The mycotoxins analyzed were aflatoxins, fumonisins, zearelenone, ochratoxin A and the following trichothecenes: deoxynivalenol, nivalenol, fusarenone X, deacetoxyscirpenol, 3-acetyl-DON, HT-2 and T-2. It was verified that the most prevalent mycotoxins were aflatoxins and fumonisins, with a prevalence of 64.6 and 63.4%, respectively, with co-occurrence of these two mycotoxins in 45.1% of the samples. Only one sample had a quantifiable concentration for zearalenone and any sample was contaminated by ochratoxin A and trichothecenes. Considering the MTLs implemented by the European Community (EC, 2006, 2007, 2013), 12% of the analyzed samples had concentrations higher than the MTL of 1000 g kg-1 for fumonisins and one sample had MTL of 10 g kg-1 higher for aflatoxins. However, considering the Brazilian legislation, 9.8% of the samples had levels above the MTL of 5000 g kg-1 of fumonisins (BRASIL, 2011, 2013, 2017). This is the first research that evaluates the occurrence of mycotoxins analyzed by LC-MS/MS in Peruvian purple maize and identifies that maize may constitute a source of intoxication, posing a risk to public health. Controls are required in the production chain of this grain and the implementation of legislation with MTLs of mycotoxins.

Natural occurrence of nivalenol and mycotoxigenic potential of Fusarium graminearum strains in wheat affected by head blight in Argentina

The principal agents of Fusarium head blight in the main cropping area of Argentina were investigated in heavily infected samples. The ability of the isolates to produce trichothecenes was determined by GC and HPLC. Fusarium graminearum was the predominant species and of 33 isolates, 10 produced deoxinivalenol (DON) (0.1- 29 mg kg-1), 13 produced both deoxinivalenol (1.0- 708 mg kg-1) and nivalenol (0.1- 6.2mg kg-1), 12 produced 3-acetyldeoxinivalenol (0.1- 14 mg kg-1), 13 produced 15-acetyldeoxinivalenol (0.1- 1.9 mg kg-1), 10 produced Fusarenone X (0.1- 2.4 mg kg-1) and 7 produced zearalenone (0.1- 0.6 mg kg-1). These results suggest that F. graminearum strains isolated from the wheat growing regions in Argentina belong to DON chemotype. Although some strains produced both deoxinivalenol and nivalenol, nivalenol was produced in lower levels. The natural occurrence of nivalenol in wheat affected by head-blight collected in the main production area during two years (2001-2002) was also determined. From 19 samples 13 were contaminated with deoxinivalenol in a range of 0.3 to 70 mg kg-1and 2 samples with both deoxinivalenol (7.5 and 6.7 mg kg-1) and nivalenol (0.05 and 0.1 mg kg-1), respectively. This is the first report of natural occurrence of nivalenol in wheat cultivate in Argentina.

O principal causador de giberela no trigo na Argentina e sua capacidade de produzir tricotecenos foram estudados por GC e HPLC em amostras altamente infectadas. A espécie predominante foi Fusarium graminearum, sendo que de um total de 33 isolados, 10 produziram deoxinivalenol (0,1-29 mg kg -1), 13 produziram deoxinivalenol (1,0-708 mg kg-1) e nivalenol (0,1-6,2 mg kg-1), 12 produziram 3-acetildeoxinivalenol (0,1-14 mg kg-1), 13 produziram 15-acetildeoxinivalenol (0,1-1,9 mg kg-1), 10 produziram fusarenona X (0,1- 2,4 mg kg-1) e 7 produziram zearalenona (0,1- 0,6 mg kg-1). Esses resultados sugerem que as cepas de F. graminearum isoladas de trigo cultivado na Argentina pertencem ao quimiotipo DON. Embora algumas cepas tenham produzido tanto DON quanto NIV, NIV foi produzido em quantidade inferior ao DON. A ocorrência natural de nivalenol em trigo afetado pela giberela coletado na principal área de produção durante dois anos (2001-2002) foi também determinada. De 19 amostras, 13 estavam contaminadas com deoxinivalenol na faixa de 0,3 a 70 mg kg-1 e 2amostras continham tanto deoxinivalenol (7,5 e 6,7 mg kg-1) quanto nivalenol (0,05 e 0,1 mg kg-1), respectivamente. Esse é o primeiro relato da ocorrência de nivalenol em trigo cultivado na Argentina.

Production of mycotoxins by Fusarium graminearum isolated from small cereals (wheat, triticale and barley) affected with scab disease in Southern Brazil

Fusarium fungi are known to be pathogenic for plants and mycotoxin producers. The in vitro production of deoxynivalenol and zearalenone was qualitatively evaluated in 24 different isolates of Fusarium graminearum collected from small cereals associated with the scab disease, in southern Brazil. Isolates were cultivated in rice during 14 days at 28ºC. Cultivates were extracted with methanol:water (40:60 v/v) and analyzed by thin layer chromatography. Other trichothecenes (diacetoxyscirpenol, fusarenon-X, neosolaniol and nivalenol) and zearalenol, often produced by Fusarium, were also analyzed. In the conditions used, it was possible to detect zearalenone and deoxynivalenol in 67% and 33% of the isolates, respectively. The presence of zearalenol, diacetoxyscirpenol and fusarenone was also detected. None of the isolates was found to produce nivalenol or neosolaniol.

Fungos do gênero Fusarium são bem conhecidos como patógenos para plantas e como produtores de micotoxinas. O objetivo deste trabalho foi avaliar qualitativamente a produção "in vitro" de desoxinivalenol e de zearalenona, em 24 diferentes isolados de Fusarium graminearum coletados a partir de cereais associados à doença Giberela na Região Sul do Brasil. Os isolados foram cultivados em arroz, durante 14 dias, a 28ºC. Os cultivos foram extraídos com metanol:água (40:60, v/v) e analisados por cromatografia em camada delgada. Outros tricotecenos (diacetoxiscirpenol, fusarenona-X, neosolaniol e nivalenol) e zearalenol, freqüentemente produzidos por Fusarium, também foram avaliados. Nas condições utilizadas, foi possível determinar o perfil de produção dessas micotoxinas, sendo que 67% dos isolados produziram zearalenona e 33% dos isolados produziram desoxinivalenol. Também foram detectadas as presenças de zearalenol, diacetoxiscirpenol e fusarenona. Finalmente, em nenhum dos isolados estudados foram encontrados nivalenol e neosolaniol.

Production of mycotoxins by galactose oxidase producing Fusarium using different culture

The original isolate of the galactose oxidase producing fungus Dactylium dendroides, and other five galactose oxidase producing Fusarium isolates were cultivated in different media and conditions, in order to evaluate the production of 11 mycotoxins, which are characteristic of the genus Fusarium: moniliformin, fusaric acid, deoxynivalenol, fusarenone-X, nivalenol, 3-acetyldeoxynivalenol, neosolaniol, zearalenol, zearalenone, acetyl T-2, and iso T-2. The toxicity of the culture extracts to Artemia salina larvae was tested.

O isolado original do fungo produtor de galactose oxidase Dactylium dendroides e outros cinco isolados de Fusarium, também produtores de galactose oxidase, foram cultivados em diferentes meios e condições, com o objetivo de estudar a produção de onze micotoxinas características do gênero Fusarium: moniliformina, ácido fusárico, deoxinivalenol, fusarenona- X, nivalenol, 3-acetildeoxinivalenol, neosolaniol, zearalenol, zearalenona, acetil T-2 e iso T-2. A toxicidade dos extratos obtidos nos diferentes cultivos foi testada em larvas de Artemia salina.