Effect of fungicides commonly used for Fusarium head blight management on growth and fumonisin production by Fusarium proliferatum.

Fumonisin occurrence was reported in wheat grains and F. proliferatum has been suggested to be the main contributor to its presence in wheat. Thus, a survey was performed in order to study the impact of four commercial fungicides used in Argentina for controlling Fusarium head blight disease (epoxiconazole+metconazole, tebuconazole, pyraclostrobin+epoxiconazole, and prothioconazole) on growth and fumonisin production of two F. proliferatum strains in relation to water activity (aW; 0.99, 0.97, 0.95) and temperature (15°C and 25°C). Most fungicides reduced growth rates when compared to the control (reduction increased as fungicide concentration increased), and reduced fumonisin production when they were used at high doses; however, most fungicides enhanced fumonisin production at sublethal doses, with the exception of prothioconazole. Thus, fungicides used for FHB management could enhance fumonisin production by F. proliferatum strains present in wheat grains.

Influência da qualidade micotoxicológica e nutricional de híbridos de milho no custo da ração de frangos de corte / Influence of mycotoxicological and nutritional quality of maize hybrids on broiler chickens feed cost

Objetivou-se avaliar as variáveis micotoxicológicas e nutricionais de híbridos de milho com diferentes características que influenciam no custo da ração para frangos de corte. Foram avaliados 26 híbridos de milho geneticamente modificados nas safrinhas de 2016 e 2017, com diferentes germoplasmas, textura de endosperma e duração do ciclo. Nos híbridos, foram avaliados grãos avariados, fumonisinas (B1+B2) (FUM), aflatoxinas (B1+B2+G1+G2) (AFLA), zearalenona (ZEA), deoxinivalenol (DON), umidade, proteína bruta (PB), energia metabolizável aparente corrigida para balanço de nitrogênio (EMAn), aminoácidos digestíveis para aves (lisina, metionina, cistina e treonina) e o respectivo custo da ração inicial para frangos de corte, que foi calculada pelo custo mínimo. A prevalência de FUM, AFLA, ZEA e DON foi de 90, 17, 33 e 0%, com médias de 3067, 1, 38 e 0µg/kg nos dois anos, respectivamente. A média de EMAn e PB foi de 3264kcal/kg e 8,02%, respectivamente, e diferiu (P<0,05) nos dois anos. O custo da ração foi influenciado significativamente (P<0,05) por FUM, PB, EMAn nos dois anos. Híbridos com tecnologia Viptera apresentam menor concentração por FUM e menor custo da ração. Híbridos de ciclo precoce têm menor concentração de FUM, maiores percentuais de PB e de aminoácidos digestíveis e menor custo da ração.(AU)

The objective of this study was to evaluate the mycotoxicological and nutritional variables of maize hybrids with different characteristics that influence the broiler chicken's feed costs. In 2016 and 2017 winter crops, 26 genetically modified hybrids of maize with different germplasm, endosperm texture and cycle duration were evaluated. The analyzed variables were damaged grains, fumonisins (B 1 +B 2 ) (FUM), aflatoxins (B 1 +B 2 +G 1 +G 2 ) (AFLA), zearalenone (ZEA), deoxynivalenol (DON), moisture, crude protein (CP), apparent metabolizable energy corrected for nitrogen balance (AMEn), digestible amino acids for poultry (lysine, methionine, cystine and threonine) and the respective cost of the initial feed for broiler chickens calculated at the minimum cost. The prevalence of FUM, AFLA, ZEA and DON was 90, 17, 33 and 0%, with means of 3067, 1, 38 and 0µg/kg in the two years, respectively. The mean of AMEn and CP was 3264kcal/kg and 8.02%, respectively, and differed (P< 0.05) in the two years. The feed cost was significantly influenced (P<0.05) by FUM, PB, AMEn in two years. Hybrids with Viptera technology show lower concentration per FUM and lower feed cost. Early cycle hybrids have lower concentrations of FUM, higher percentages of CP and digestible amino acids, and lower feed costs.(AU)

Fumonisinas en alimentos a base de maíz: desarrollo y validación analítica de la metodología

Las micotoxinas son metabolitos secundarios producidos por especies de hongos que contaminan los productos agrícolas. Dentro del género Fusarium, las fumonisinas B1, B2 y B3 son las más relevantes, crecen en forma endógena en el maíz y presentan efectos tóxicos para la salud humana y animal. Como objetivo se planteó desarrollar y validar una metodología analítica para cuantificar fumonisinas en alimentos a base de maíz. La determinación de fumonisinas consistió en tres etapas: extracción con metanol:agua, purificación con columnas de extracción en fase sólida y, separación, detección y cuantificación en cromatógrafo líquida de alta resolución con detector de fluorescencia (HPLC/FL) previa derivatización de los analitos. Se estandarizaron las condiciones operativas de la metodología analítica, particularmente las condiciones de extracción y purificación de la muestra, la etapa de derivatización y las condiciones cromatográficas. Se validó la técnica cumpliendo con los criterios de aceptabilidad especificados para los parámetros de selectividad para FB1, FB2 y FB3, linealidad (R2 mayor a 0,97), sensibilidad (LOD y LOQ adecuados) y precisión (repetibilidad y reproducibilidad entre analistas). La recuperación obtenida fue de 104% para FB1, 88% para FB2 y 79% para FB3. Por lo tanto, el método propuesto proporciona una herramienta eficaz y confiable para el estudio de la contaminación por fumonisinas en alimentos.

Factores extrínsecos e intrínsecos asociados a poblaciones fúngicas micotoxigénicas de granos de maíz (Zea mays L) almacenados en silos bolsa en Argentina / Extrinsic and intrinsic factors associated with mycotoxigenic fungi populations of maize grains (Zea mays L.) stored in silobags in Argentina

Con el objeto de caracterizar las poblaciones fúngicas, en particular las especies potencialmente micotoxigénicas, que pueden contaminar los granos de maíz almacenados en silos bolsa con un contenido de humedad superior al recomendado como seguro, se evaluaron 270 muestras extraídas al inicio, a los 90 días y al final de un período de almacenamiento de 5 meses. En dichas muestras se cuantificó e identificó la biota fúngica y se determinó la contaminación con fumonisinas y aflatoxinas. Asimismo, se evaluó el efecto de factores extrínsecos (ambiente), intrínsecos (granos) y tecnológicos (ubicación de los granos en el perfil del silo bolsa) sobre las poblaciones totales y micotoxigénicas. El pH de los granos y el nivel de O2 se redujeron significativamente a los 5 meses, mientras que la concentración de CO2 se incrementó en igual período. Los recuentos totales de la micobiota fueron significativamente mayores en los granos ubicados en el estrato superior del silo bolsa. Se identificaron especies micotoxigénicas de Fusarium, Aspergillus, Penicillium y Eurotium. La frecuencia de aislamiento de Fusarium verticillioides se redujo al final del almacenamiento y Aspergillus flavus solo se aisló en el inicio del almacenamiento. Los recuentos de Penicillium spp. y Eurotium spp. se incrementaron al final del almacenamiento. El 100 % de las muestras presentaron contaminación con fumonisinas, con niveles máximos de 5,707 mg/kg, mientras que las aflatoxinas contaminaron el 40 % de las muestras con niveles máximos de 0,0008 mg/kg. Las condiciones ambientales y de sustrato generadas durante el almacenamiento produjeron cambios en la composición de las poblaciones fúngicas y limitaron el desarrollo de hongos micotoxigénicos y la producción de micotoxinas.

In order to determine the behavior of mycotoxin-producing fungal populations linked with silobags stored corn grains with a moisture content greater at the recommended as safe, 270 samples taken in three times (beginning, 90 days, final) over a five month period of storage were evaluated. The fungal biota was quantified and identified and the contamination with fumonisin and aflatoxin was determined. Extrinsic factors (environment), intrinsic factors (grains) and technological factors (location of the grains in the profile of silobag) were taken into account to evaluate the presence and quantity of total and mycotoxigenic fungal populations. The pH of grains and O2 levels were significantly reduced after five months, while CO2 concentration increased in the same period. The total counts of mycobiota were significantly higher in grains located in the top layer of silobag. Mycotoxigenic species of Fusarium, Aspergillus, Penicillium and Eurotium were identified. The frequency of isolation of Fusarium verticillioides decreased at the end of storage and Aspergillus flavus was isolated only at the beginning of storage. The counts of the Penicillium spp. and Eurotium spp. were increased at the end of storage. Fumonisin contamination was found in all the samples (100 %) with maximum levels of 5.707 mg/kg whereas aflatoxin contaminated only 40 % with maximum levels of 0.0008 mg/kg. The environmental and substrate conditions generated during the storage limited the development of mycotoxigenic fungi and mycotoxin production.

[Extrinsic and intrinsic factors associated with mycotoxigenic fungi populations of maize grains (Zea mays L.) stored in silobags in Argentina]. / Factores extrínsecos e intrínsecos asociados a poblaciones fúngicas micotoxigénicas de granos de maíz (Zea mays L.) almacenados en silos bolsa en Argentina.

In order to determine the behavior of mycotoxin-producing fungal populations linked with silobags stored corn grains with a moisture content greater at the recommended as safe, 270 samples taken in three times (beginning, 90 days, final) over a five month period of storage were evaluated. The fungal biota was quantified and identified and the contamination with fumonisin and aflatoxin was determined. Extrinsic factors (environment), intrinsic factors (grains) and technological factors (location of the grains in the profile of silobag) were taken into account to evaluate the presence and quantity of total and mycotoxigenic fungal populations. The pH of grains and O2 levels were significantly reduced after five months, while CO2 concentration increased in the same period. The total counts of mycobiota were significantly higher in grains located in the top layer of silobag. Mycotoxigenic species of Fusarium, Aspergillus, Penicillium and Eurotium were identified. The frequency of isolation of Fusarium verticillioides decreased at the end of storage and Aspergillus flavus was isolated only at the beginning of storage. The counts of the Penicillium spp. and Eurotium spp. were increased at the end of storage. Fumonisin contamination was found in all the samples (100%) with maximum levels of 5.707mg/kg whereas aflatoxin contaminated only 40% with maximum levels of 0.0008mg/kg. The environmental and substrate conditions generated during the storage limited the development of mycotoxigenic fungi and mycotoxin production.

Micotoxicosis y micotoxinas: generalidades y aspectos básicos / Mycotoxicosis and mycotoxins: generalities and basic aspects

El término micotoxicosis hace referencia a un amplio grupo de intoxicaciones causadas por la inhalación, el contacto directo o la ingestión de alimentos que han sido contaminados con micotoxinas, las cuales son metabolitos tóxicos producidos por una gran variedad de hongos filamentosos, entre los que se destacan los géneros Aspergillus, Fusarium, Claviceps, Penicillium y Stachybotrys. Esta es una revisión que analiza el impacto clínico de ciertas micotoxinas (aflatoxinas, ocratoxinas, fumonisinas, tricotecenos) en la génesis de las micotoxicosis en los seres humanos.

Mycotoxicosis refers to a large group of poisoning by inhalation, contact or ingestion of food that has been contaminated with mycotoxins, toxic secondary metabolites, produced by a variety of filamentous fungi, Aspergillus, Fusarium, Claviceps, Penicillium and Stachybotrys. This is a review that analyzes the clinical impact of certain mycotoxins (aflatoxins, ochratoxins, fumonisins, trichothecenes) in the genesis of mycotoxicosis in human beings.

Equine leukoencephalomalacia (ELEM) due to fumonisins B1 and B2 in Argentina / Leucoencefalomalacia equina devida a fumonisinas B1 e B2 na Argentina

In August 2007 an outbreak of neurological disease and sudden death in Arabian horses occurred in a farm located in Coronel Rosales County, Buenos Aires Province, Argentina. The animals were on a pasture of native grasses and supplemented ad libitum with corn kernels and wheat bran. Three horses were observed having acute neurologic signs including blindness, four leg ataxia, hyperexcitability, aimless walking and circling, followed by death in two of them. Four other horses were found dead overnight without a history of neurologic signs. The morbidity, mortality and lethality rates were 11.6 percent, 10 percent and 85.7 percent, respectively. Grossly, the brain showed focal areas of hemorrhage, brown-yellow discoloration and softening of the sub-cortical white matter. The microscopic brain lesions consisted of extensive areas of malacia within the white matter of the cerebral hemispheres, brainstem and cerebellum, characterized by rarefaction of the white matter with cavitations filled with proteinaceous edema, multifocal hemorrhages and mild infiltration by neutrophils, and rare eosinophils. Swollen glial cells with abundant eosinophilic cytoplasm, distinct cell borders, intracytoplasmic deeply eosinophilic globules and eccentric, hyperchromatic, occasionally pyknotic nucleus were present throughout the areas of rarefaction hemorrhage, edema and necrosis. The feed supplements contained 12,490µg/kg of fumonisin B1 and 5,251µg/ kg of fumonisin B2. This is the first reported outbreak of ELEM associated with consumption of feed supplements containing high concentrations of fumonisins in Argentina.

Em agosto de 2007, ocorreu um surto de doença neurológica e morte súbita em cavalos árabes em uma propriedade localizada no município de Coronel Rosales, na província de Buenos Aires, Argentina. Os animais estavam em pasto nativo e eram suplementados ad libitum com grãos de milho e farelo de trigo. Três cavalos foram observados com sinais neurológicos agudos, incluindo cegueira, ataxia nas quatro pernas, hiperexcitabilidade, e andar sem rumo e em círculo, seguidos de morte em dois animais. Outros quatro cavalos foram encontrados mortos durante a noite sem histórico de distúrbios neurológicos. A mortalidade, morbidade e letalidade foram de 11,6 por cento, 10 por cento e 85,7 por cento, respectivamente. Macroscopicamente, o cérebro tinha áreas focais de hemorragia, coloração amarelada e amolecimento da substância branca sub-cortical. Microscopicamente, as lesões cerebrais consistiram de extensas áreas de malácia na substância branca dos hemisférios cerebrais, do tronco encefálico e do cerebelo. Estas lesões da substância branca se caracterizaram por rarefação, cavidades contendo fluido proteináceo (edema), hemorragias multifocais e moderado infiltrado por neutrófilos e raros eosinófilos. Células gliais tumefeitas com abundante citoplasma eosinifílico, limites celulares evidentes, globules citoplasmáticos eosinofílicos, e núcleo excéntrico, hipercromático e ocasionalmente picnótico foram observadas nas areas de rarefacção, edema, hemorragias e necrose. Os suplementos alimentares continham 12.490µg/kg de fumonisina B1 e 5.251µg/ kg de fumonisina B2. Este é o primeiro surto reportado na Argentina de leucoencefalomalácia equina associado ao consumo de suplementos alimentares contendo altas concentrações de fumonisinas.

Consumo de fumonisinas y daños a la salud humana / Fumonisin intake and human health

Las fumonisinas son una familia de micotoxinas que contaminan al maíz, alteran el metabolismo de los esfingolípidos y del folato, se asocian con defectos del tubo neural y están catalogadas por la Agencia Internacional de Investigación en Cáncer (IARC por sus siglas en inglés) como posibles carcinógenos humanos. Debido a que en México los derivados de maíz constituyen una parte importante de la dieta y existe alta prevalencia de población genéticamente susceptible a la deficiencia de folato, en este ensayo se presentan las evidencias mundiales y nacionales de la exposición a fumonisinas y la relevancia que para México representa la evaluación de esta exposición.

Fumonisins are mycotoxins that contaminate maize, disrupt the folate and sphingolipid metabolism, are associated with neural tube defects, and are considered by the International Agency for Research on Cancer (IARC) as possible human carcinogens. Since maize-based foods are significant components of the Mexican diet and there is a high prevalence of genetic susceptibility for folate deficiency among Mexicans, this essay presents international and national evidence of fumonisin exposure and the relevance that such exposure represents for Mexico.

Avaliação da micoflora e ocorrência de micotoxinas em cascas de amendoim em diferentes estágios de maturação da vagem / Evaluation of mycoflora and occurrence of mycotoxins in peanut hulls at different pod maturation stages

As cascas de amendoim (Arachis hypogaea L.) são de grande importância para confecção de cama de frangos, de gado de leite e como fonte de fibras para ruminantes, portanto a elucidação dos mecanismos de contaminação por fungos toxigênicos e por micotoxinas em amendoim é imprescindível, especialmente para que medidas preventivas possam ser tomadas. Realizou-se, este trabalho, em Junqueirópolis, Estado de São Paulo, Brasil. Os principais fungos isolados nas cascas de amendoim foram Fusarium ssp. (78,75 por cento), Rhizopus ssp. (14,1 por cento) e A. flavus (11,75 por cento). No solo foram isolados Penicillium spp., Fusarium spp. e Aspergillus flavus, entre outros. Aflatoxinas foram detectadas em amostras de cascas de amendoim a partir do estágio de granação em concentrações que variaram de 5,42 μg/kg a 218,52 μg/kg. Ácido ciclopiazônico e fumonisinas B1 e B2 não foram detectadas. A presença de A. flavus e aflatoxinas nas amostras, revela a importância de um controle das cascas de amendoim antes de sua utilização. Boas práticas agrícolas são indicadas para região, uma vez que a contaminação das vagens ocorreu antes da colheita.

Peanut (Arachis hypogaea L.) hulls are very important because they are used as litter to poultry and dairy cattle and as fiber source to cattle. The elucidation of the peanuts contamination mechanisms by toxigenic fungi and their mycotoxins is vital, specially for prevention measurements. The peanuts total mycoflora and mycotoxin contamination were analyzed in plants sampled in Junqueirópolis, in São Paulo State (Brazil) at different stages of the pod maturity. The prevalent mycoflora in peanut hulls were Fusarium spp., Rhizopus spp. and Aspergillus flavus. In soil under the peanut crop, the genus Penicillium spp., Fusarium spp. and A. flavus were detected. Aflatoxins were detected in peanut hull samples since filling pod stage in concentrations from 5.42 μg/kg to 218.52 μg/kg. Cyclopiazonic acid and fumonisins were not detected. The A. flavus presence and the detection of aflatoxins indicate the importance of quality control of peanut hulls before their utilization, and the adoption of agricultural practices showed to avoid the contamination since the peanut pods contamination happened before the harvest.

Fumonisins in corn cultivars in the state of São Paulo

Twenty three samples, belonging to 19 corn cultivars with distinct types of germoplasms, endosperm and length of vegetative cycle, were analyzed for fumonisins B1 and B2. The cultivars were grown in experimental fields in three locations (Votuporanga, Ribeirão Preto and Capão Bonito) within the State of São Paulo, Brazil, during the 97/98 crop. All samples were contaminated with fumonisins with concentrations ranging from 1.63 µg/g to 25.69 µg/g with an average of 5.61 µg/g for FB1 and from 0.38 µg/g to 8.60 µg/g with an average of 1.86 µg/g for FB2. In terms of fumonisins, these high levels put the corn cultivated in São Paulo among the most contaminated in the world reported to date.

Vinte e três amostras, representando 19 cultivares de milho com diferentes tipos de germoplasma, de endosperma e ciclo vegetativo, foram avaliadas quanto ao teor de fumonisinas em três Estações Experimentais do Instituto Agronômico (Capão Bonito, Ribeirão Preto e Votuporanga) em São Paulo, Brasil, durante a safra de 97/98. Todos os cultivares analisados estavam contaminados com fumonisinas em níveis que variaram de 1.63 µg/g a 25.69 µg/g e uma média de 5.61 µg/g FB1 e de 0.38 µg/g a 8.60 µg/g e uma média de 1.86 µg/g FB2. Estes níveis tão elevados colocam o milho cultivado no Estado de São Paulo entre os mais contaminados do mundo em termos de fumonisinas.

Avaliaçäo de métodos para determinaçäo de fumonisinas B1 e B2 em milho / Evaluation of analytical methods and optimization of conditions for the determination of fumonisins B1 and B2 in corn

Sistemas de extraçäo e limpeza foram avaliados para determinaçäo de fumonisimas em milho. O método descrito por Sydenham et alii (1992) apresentou a melhor limpeza. A recuperaçäo encontrada, no entanto, estava abaixo de 50 (por cento) para fumonisinas B1 e B2 (FB1 e FB2). O método foi modificado e a extraçäo com metanol/água (3+1) foi mantida, os volumes de solventes no condicionamento e lavagem da coluna de troca aniônica forte foram aumentados para 10 mL e o volume e composiçäo do solvente de eluiçäo alterado para 20 mL metanol/ácido acético (95+5). Após estas modificaçöes a recuperaçäo elevou-se para a faixa de 93 a 96 (por cento) para FB1 e 69 a 85 (por cento) para FB2. O solvente de eluiçäo por CLAE com detecçäo por fluorescência foi modificado para acetonitrila/água/ácido acético glacial (50+50+0,5) durante os primeiros 15 minutos com troca para acetonitrila pura até o final da corrida. As condiçöes de derivaçäo das FB1 e FB2 com o o-ftaldialdeído (OPA) foram também otimizadas empregando 100 L de extrato com 200 L do reagente OPA entre 5 - 15oC por 60 segundos. As novas condiçöes melhoram os limites de detecçäo para 20 e 40 ng/g FB1 E FB2, respectivamente, e o desvio padräo relativo entre duplicatas para 0,6(por cento) para FB1 e 2,2(por cento) para FB2. (AU)

Extraction and clean up systems were evaluated for the determination of fumonisins in com. The best clean up was found in the method described by Sydenham et alii (1992). Recovery, nonetheless, was found to be bellow 50% for fumonisins B I and B2 (FB 1 and FB2). The method was modified and methanol/water (3+ I) was kept as the extraction solvent, the volumes of the anionic Exchange column conditioning and washing solventes were increased to 10 mL and both the volume and the composition of the eluting solvente were altered to 20 mL methanol/acetic acid (95+5). After these modifications were introduced the method recovery was 95 to 96% for FB 1 and 69 to 72% for FB2. The eIution solvente for the HPLC with fIourescence detection step was also modified to acetonitri- le/water/acetic acid (50+50+0,5) during the first 15 minutes followed by purê acetonitrile for the rest of the run. The conditions employed during the derivatization reaction of fumonsins with o-phtaldialdehy- de (OPA) were also optimized to utilize 100 L sample extract and 200 L OPA solution at 5 - 15 T during60 seconds.The newconditions improved the detection limits to 20 and 40 ng/g for FB 1 and FB2, respectively, and to an average standard deviation between duplicates of 0,6% for FB I and for FB2. (AU) .