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.

Mycotoxin in medicinal/aromatic Herbs: a review / Micotoxinas en hierbas medicinales y/o aromaticas: Revisión

Owing to their conditions of production, and sometimes to poor storage and transportation conditions, herbal products are susceptible to fungal contamination and development. This can lead to the accumulation of mycotoxins in this kind of commodities. Consequently, herbal products can be contaminated with fungal toxins, such as aflatoxins, ochratoxins and other mycotoxins, which pose a serious risk to public health. This paper reviews the main aspects regarding mycotoxin contamination of medical/aromatic herbs, in the context of the importance of this product in a global market. Moreover, the effect of processing on final contamination of derived foods, as well as the analytical methodology commonly employed in fungal and mycotoxin analysis in this type of products was reviewed.

Debido a sus condiciones habituales de producción, así como a condiciones inadecuadas de almacenamiento y de transporte, los productos a base de plantas medicinales o aromáticas son susceptibles a la contaminación por mohos, lo que puede conducir a la acumulación de toxinas fúngicas tales como las aflatoxinas, ocratoxinas y otras micotoxinas, lo que supone un grave riesgo para la salud pública. Este artículo revisa los principales aspectos de la contaminación por micotoxinas de las hierbas medicinales y/o aromáticas, teniendo en cuenta el contexto de este producto en un mercado globalizado, así como el efecto del procesado sobre la contaminación final de estos productos. También se revisa la metodología más comúnmente empleada en el análisis de mohos y micotoxinas en este tipo de productos.

Aspergillus sp. y aflatoxinas en plantas medicinales y té comercial / Aspergillus sp. and aflatoxins in medicinal plants and commercial tea

The objective of this work is to determine the incidence of Aspergillus sp. (aflatoxins’s typesetters) fungus species in medicinal plants and bags for infusions, as well as to evaluate the relationship between the appearance of these fungi and their toxins in such substrata. A sample of 24 medicinal plants and 20 small bags of infusion used by the Cuban population were processed in order to determine the incidence of Aspergillus sp. (aflatoxins’s typesetters) fungus species, as well as aflatoxins's production. A microbiological test by means of Agar Malta for culture, and aflatoxins's determination by means of high precision thin layer chromatography were made. Out of the sample studied, Aspergillus ustus, A. flavus and A. parasiticus appeared in 48 percent, but the concentration of aflatoxins B1 detected did not exceed the maximum values of 10 parts per billion (ppb), already established worldwide. Taking into account the increasing use of medicinal plants and the results stated in this work, new regulations for the sake of controlling the appearance of these fungi and their toxins are required, although it becomes necessary to validate fast and specific analytical methods.

El objetivo de este trabajo es determinar la incidencia de especies de hongos del genero Aspergillus sp. (formadores de aflatoxinas) en plantas medicinales y bolsas para infusiones, así como evaluar la relación entre la aparición de estos hongos y sus toxinas en dichos sustratos. Se procesaron 24 muestras de plantas medicinales y 20 bolsitas de infusión utilizadas por la población cubana, para determinar la incidencia de especies de hongos del genero Aspergillus sp. así como la producción de aflatoxinas. Se realizó análisis microbiológico utilizando Agar- Malta como medio de cultivo, y se realizó la determinación de aflatoxinas por cromatografía de capa delgada de alta precisión. De las muestras estudiadas, aparecieron Aspergillus ustus, A. flavus, A. parasiticus en el 48 por ciento, pero la concentración de aflatoxina B1 detectada no excedió los valores máximos establecidos internacionalmente de 10 ppb. Teniendo en cuenta el creciente uso de las plantas medicinales y los resultados expuestos en este trabajo, se hace necesario establecer nuevas regulaciones en aras de controlar la aparición de estos hongos y sus toxinas en las mismas, aunque para ello se hace necesario validar métodos analíticos rápidos y específicos.

Validity of method for determining deoxynivalenol through high performance liquid chromatography with detection in the ultraviolet in wheat samples / Validación de un método para la determinación de deoxinivalenol por cromatografía líquida de alta resolución con deteccíon ultravioleta en muestras de trigo

With the purpose of evaluating the wheat grain and wheat flour contamination by Deoxynivalenol (DON) in the municipality of Chapeco-SC, and standardize an useful method to detect this mycotoxin by High Performance Liquid Chromatography (HPLC), six samples of wheat grains from different storage location, and one sample of wheat grain from the flour milling industry were obtained during in the month of august 2008. Samples belong to a corporation from Chapeco-SC that stores and processes wheat grains, flour and wheat middlings, among other products. The extraction has been carried out with methanol: water (100: 100 v / v), filtered paper filter and applied in immunoaffinity column specific DON. After the wash with water column, the toxin was eluted with methanol. The detection and quantification Deoxynivalenol in samples was carrid out through the method of HPLC in the UV-visible with detection 244 nm. The 6 analyzed samples of wheat grain showed DON levels within 7.0 and 10.1 ppb, while the wheat flour contained 90.2 ppb. DON contents in wheat grains and wheat flour are lower than the limits claimed by the studied corporated importers and the international legislation.

Con el objetivo de evaluar la contaminación por Deoxinivalenol (DON) en granos y harina del trigo en la municipalidad de Chapeco-SC y estandarizar un método de deteccíon para este micotoxina por cromatografía líquida de alta resolución (CLAR), se procesaron durante el mes de agosto de 2008, seis muestras de granos del trigo en diferentes situaciones de almacenamiento y una muestra de harina de trigo de un molino . Las muestras pertenecen a una cooperativa de Chapeco-SC que procesa y almacena granos y harinas de trigo entre otros productos. La extracción de la micotoxina se obtuvo con metanol: agua (100: 100 v / v), filtrado en papel filtro y aplicado a una columna de inmunoafinidad específica (DON). Después del lavado de la columna con agua, la toxina fue elucidada con metanol. La detección y cuantificación de Deoxinivalenol en las muestras se determinó por el método CLAR en el UV- visible con una longitud de onda de 244 nm. Las 6 muestras analizadas del grano, mostraron que el DON nivela entre 7,0 y 10, 1 ppb, mientras la harina del trigo alcanzó las 90,2 ppb. Los niveles de DON en los granos y harina de trigo tienen límites menores que los exigidos por las cooperativas importadoras estudiadas y la legislación internacional.

Detection of fumonisin producing Fusarium verticillioides in paddy (Oryza sativa L. ) using polymerase chain reaction (PCR) / Detecção de Fusarium verticillioides produtor de fumonisina em arroz empregando reação de polimerase em cadeia

The study reports the occurrence of fumonisin producing Fusarium verticillioides in 90 samples of stored paddy (Oryza sativa L.)collected from different geographical regions ofKarnataka, India. Fumonisin producing F. verticillioides was identified based on micromorphological characteristics and PCR using two sets of primers. One set of primers was F. verticillioides species specific, which selectively amplified the intergenic space region of rDNA. The other set of primers was specific to fumonisin producing F. verticillioides. Eight paddy samples were positive for F. verticillioides. Eleven isolates obtained from these samples were capable of producing fumonisin.

O estudo relata a ocorrência de Fusarium verticillioides produtor de fumonisina em 90 amostras de arroz armazenado, coletado de diferentes regiões geográficas de Karnataka, Índia. F. verticillioides produtor de fumonisina foi identificado baseado em características micromorfológicas e PCR empregando dois sets de primers. Um dos sets era F. verticillioides especie-específico, que amplificava seletivamente a região do espaço intergênico do rDNA. O outro set de primers era especifico para F. verticillioides produtor de fumonisina. Oito amostras de arroz foram positivas para F. verticillioides. Onze isolados obtidos dessas amostras foram produtores de fumonisina.

Mycotoxin residues in new chicken breast meat products

Thirty random poultry meat products fifteen from each [Kiev and Cordon bleu] were collected from different groceries and supermarkets in Cairo and Giza Governorates were analyzed for determination of some mycotoxin residues. Aflatoxins [AFs] and ochratoxin A [OA] could be detected with different percentages and levels, the highest percentages [86.66%] of AFB1 were present in coat of Kiev and Cordon bleu, while the lowest percentage [13.33%] for G[1] and G[2] in the meat part of Kiev and M[1] and M[2] in its coat. OA was detected in all tested samples of Cordon bleu coat, but the lowest percentage [46.66%] in the Cordon bleu core "cheese". On the other hand, the highest estimated level [22.0 microg/kg] of AFB[1] was estimated in Cordon bleu coat and 10.6 microg/kg OA in Kiev coat. The lowest level was found to be 1.1 microg/kg for each of AFs [B[1], B[2], G[1] G[2] in Kiev coat and 1.1 microg/kg OA in each of meat and butter of Kiev and meat and cheese of Cordon bleu samples. The public health significance of mycotoxin residues and measures to prevent contamination of meat products with mycotoxins were discussed

Production of mycotoxins by galactose oxidase producing "Fusarium" using different culture media

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, wich are characteristic of the genus "Fusarium": moniliform, fisaric acid, deoxyvalenol, fusarenone-X, nivalenol, 3-acetyldeoxynivalenol, neosolaniol, zearakenol, zeralenone, acetyl T-2, and iso T-2. The toxicity of the culture extractes to "Artemia salina" larvae was tested

Effect of mycotoxins isolated from Penicillium nigricans on glucose-6-phosphate dehydrogenase.

A new mycotoxin product (NMP) was isolated from the culture of mutated wild strain of P. nigricans which is less toxic and has sterol derivative. NMP (LD50 > 1 g/kg) showed antimicrobial and antineoplastic activities and does not affect the hematological parameters like RBC count and hemoglobin. It maintained normal blood glucose level by increasing the enzyme activity of glucose-6-phosphate dehydrogenase (EC-1.1.1.49; G-6-PDH) by 30%. It also maintained the normal ion balance in the blood of mice. NMP decreased Km value of glucose-6-phosphate dehydrogenase and thus increased substrate affinity of the enzyme. Reduction of toxicity of NMP has been well explained by higher activity of G-6-PDH which is highly specific for production of NADPH.

Neuropharmacological studies on Fusarium toxins--I: Total toxin extract from Fusarium moniliforme.

The neuropharmacological profile of the total fungal extract of F. moniliforme (FM) has been investigated. FM produced dose related decrease in spontaneous motor activity (SMA) and exploratory activity, potentiated pentobarbitone hypnosis and the anticonvulsant actions of phenobarbitone and phenytoin against MES seizures, potentiated PTZ and tryptamine seizures, antagonised reserpine induced syndrome, attenuated tetrabenazine and morphine induced catalepsy and potentiated haloperidol catalepsy. FM showed per se antinociceptive activity and potentiated morphine analgesia. It increased rectal temperature, antagonised reserpine and apomorphine hypothermia and potentiated the hyperthermic response of haloperidol and 5-hydroxytryptophan (5-HTP) and hypothermic response of betaphenylethylamine (PEA) and L-dopa. FM had no per se effect on amphetamine lethality, but enhanced the lethality induced by morphine in aggregated animals. Stereotypy by amphetamine was potentiated while that of apomorphine was not affected. The behavioural response of 5-HTP and L-dopa was potentiated. FM had no effect on swim induced behavioural despair. The effect on aggressive behavior was complex, and while the cumulative aggressive score was reduced, the onset of fighting behaviour and contact period was increased. It also inhibited clonidine induced auto mutilation. Since earlier investigation had shown that FM, like nialamide, induced non-selective inhibition of monoamine oxidase (MAO), the results were compared with those induced by nialamide. A comparative profile of action reveals that the neuropharmacological action of FM are qualitatively similar to those induced by nialamide, and likely to be due to inhibition of MAO. The investigation has practical implications because F. moniliforme is a common contaminant of cereals and fruits.

Neuropharmacological studies on Fusarium toxins--II: Total toxin extract from F. oxysporum.

The neuropharmacological activity profile of total fungal extract of F. oxysporum (FO) was investigated. FO enhanced spontaneous locomotor activity, exploratory behaviour and reduced pentobarbitone hypnosis. It had per se anticonvulsant action against maximal electroshock seizure (MES) and potentiated phenobarbitone and phenytoin in MES and also potentiated pentylenetetrazol (PTZ) convulsion. It antagonised morphine, tetrabenazine and haloperidol catalepsy. FO did not show per se analgesia or potentiation of morphine antinociception in mice, while both effects were present in rats. The effect of FO on body temperature was complex. It produced per se reduction in rectal temperature and potentiated the hypothermic responses of reserpine, apomorphine, PEA and I-dopa, and also the hyperthermic response of 5-HTP. The hyperthermic response of haloperidol was reversed by FO. It potentiated amphetamine and morphine lethality, amphetamine, PEA and apomorphine stereotypy, 5-HTP headtwitch response and post-swim grooming response. On swim-stress immobility, while the time of onset of immobility was reduced, FO did not modify the duration of immobility. On foot-shock induced aggression in paired rats, FO produced a decrease in the latency to onset of fighting behaviour and increased the total contact period and the cumulative aggressive score. FO potentiated clonidine automutilation. It has, thus, facilitated aggressive behaviour. The effects are likely to be due to the presence of fusaric acid in FO, which inhibits dopamine beta-hydroxylase and is known to have dopaminergic effects. This investigation has practical implications. since F. oxysporum is a common food contaminant.

Survey of mycotoxins in wheat and wheat products sold in health food stores of the city of Campinas, State of Säo Paulo

Trinta e oito amostras de trigo integral e produtos derivados (trigo integral 4, trigo integral laminado 1, farelo de trigo 3, germe de trigo 4, farinha de gluten 2, trigo para quibe 7, farinha de trigo integral 5, macarräo de trigo integral 11, semolina 1) foram adquiridos em lojas de produtos naturais na cidade de Campinas, SP., durante o ano de 1991 e foram analisadas para deoxinivalenol (DAS), toxinas T-2 and HT-2, T-2 triol and T-2 teatrol por cromatografia gasosa. Foram também analisadas para aflatoxinas B1, B2, G1, G2, ocratoxina A (OCHRA A), zearalenona (ZEN), e esterigmatocistina por cromatografia em camada delgada. Os resultados foram negativos para as 14 micotoxinas procuradas

Mycotoxin residues in meat and meat products

A total of 120 samples of fresh and frozen meat and meat products [minced meat, sausage, beefburger, luncheon] were examined for the prevalence of molds and mycotoxins. Fresh meat has the lowest mean mold count [1.4 x 10 4 g], while meat products showed higher counts. Aflatoxins and zearalenone were extracted from 10.8% and 15.8% of the examined samples. Aspergillus, Penicillium, Mucor and Cladosporium spp. were the main isolated molds. Also, 69.57% of the isolated A. flavus strains were capable of aflatoxins production. None of the heat treatment during conventional cooking or cold storage of meat spiked with zearalenone were found efficient to get-rid of zearalenone residues

Identification of some fungi and mycotoxins in sausage

Out of 40 samples of sausage subjected to mycological and mycotoxicological examination, the total mold contamination was abnormally high [92%] with mean count of 3.8 x 10 3. The genera of Aspergillus, yeast Penicillium were most predominant fungi isolated but in low frequency. A. niger and A. flavus constituted the most fungal contamination of sausage [65.0% and 32.5%, respectively]. When these samples were analyzed mycotoxicologically, different types of aflatoxins could be detected. AFBI, B2, G1 and G2 were detected at mean levels of 280 in 15% of samples, 160 in 2.5%, 84 in 5% and 586 ppb in 7.5% of tested samples, respectively. The detected aflatoxin in present work was associated with higher pH [5.2-8.5] and rich moisture content 36%-60%. The isolated A. flavus from sausage was inoculated in rabbits, and monitored for antibodies production which could be easily diagnosed by agglutination test. The focal necrosis and enlargement of the livers and kidneys were most obvious findings in postmortem examination of inoculated animals with A. flavus

Mycoflora, aflatoxigenic species and mycotoxins in freslhly harvested corn (Zea mays L.): a preliminary study

A micoflora, a ocorrência de espécies aflatoxigênicas e das aflatoxinas B1, B2, G1 e G2, zearalenona e ocratoxina A foram verificadas em amostras de milho recém-colhido coletadas em diferentes localidades do Estado de Säo Paulo durante 1992. A invasäo de gräos por fungos pertencentes aos gêneros potencialmente micotoxigênicos Fusarium spp. e Penicillium spp. foi elevada. Aspergillus também foi isolado mas a sua incidência foi menor comparada à dos outros dois gêneros mencionados. As espécies de Aspergillus detectadas foram: A. versicolor, A. flavus, A. niger, A. alutaceus, A. wentii, Eurotium chevalieri, Eurotium rubrum, Eurotium amstelodami and Eurotium repens. Oito espécies de Penicillium foram isoladas a saber: P. variabile, P. funiculosum, P. citrinum, P. pinophilum, P. brevicompactum, P. canescens, P. raistrikii and P. spinulosum. Embora fungos potencialmente toxigênicos tenham sido isoladas, zearalelona produzida por Fusarium spp.) e ocratoxina A (produzida por Aspergillus spp. e Penicillium spp.) näo foram encontrados nos gräos. Das dezessete cepas de A. flavus isoladas quatro eram produtoras das aflatoxinas B1 ou B1 e B2. A presença de cepas näo toxigênicas, condiçöes climáticas desfavoráveis, interaçäo entre espécies fúngicas e variedades resistentes de milho säo alguns dos fatores que isoladamente ou interagindo com outros podem explicar a ausência das micotoxinas estudadas em milho cozido em 1992 no Estado de Säo Paulo

Aflatoxins in mixed feeds for rabbits

Se analizaron 10 muestras de alimentos y una muestra de alfalfa, destinados a la alimentación de conejos, suministradas por plantas procesadoras de la provincia de Santa Fe, Argentina. Los lotes correspondientes fueron objeto de reclamo por parte de diversos establecimientos de cría y considerados posible causa de intoxicación de los animales. Se investigó el grado y tipo de contaminación fúngica y la presencia de las siguientes micotoxinas en las muestras: aflatoxinas (AFI), acratoxina A, citrinina, ácido penicílico, zearalenona (ZEA) y los tricotecenos, toxina T-2, diacetoxiscirpenol (DAS) y deoxinivalenol (DON). El recuento total de hongos se efectuó por el método de dilución en placa con agar dicloran-rosa de bengala-cloranfenicol (DRBC). El aislamiento de especies se realizó en cámara húmeda, sobre agar aspergillus flavus-parasiticus (AFPA), agar papa-dextrosa-cloranfenicol (PDAC) y agar dicloranglicerol 18 por ciento (DG18). Para la identificación de especies se empleó: agar extracto de malta (MEA), agar czapek-extracto de levadura (CYA), agar por dextrosa (PDA) y agar nitrato-glicerol 25 por ciento (G25N). La detección y cuantificación de micotoxinas se efectuó por cromatografía en capa delgada. No es posible asegurar que las intoxicaciones observadas por los criadores hayan sido originadas por micotoxinas. Sin embargo, las aflatoxinas presentes en 7/11 muestras y los altos niveles hallados en dos de ellas (200 y 300 ug/kg) pudieron ser la causa de las mismas

Microhongos filamentosos y levaduriformes asociados a pimienta negra, piper nigrum l / Filamentous microfungi and yeasts associated black pepper, piper nigrum l

Se investigó la presencia de microhongos filamentosos y levaduriformes en pimienta negra comercial, entera y molida, (Pipernigrum L.), destinada al consumo humano. Se colectaron 30 muestras en total (13 entera y 17 molida) entre Agosto de 1991 y Marzo de 1992, aplicandose dos metodologías: el método de dilución y el de siembra directa en agar agua. Por el método de dilución y siembra en PDA, se aislaron 1.388 cepas distribuídas en 20 géneros y 40 especies, los géneros de mayor frecuencia fueron: Aspergillus (63,68 porciento) en pimienta entera (PE), con una dominancia de A. fumigatus y A. flavus y un 26,74 porciento en pimienta molida (PM). El género Penicillium fue el segundo en importancia en PE (17,43 porciento) y levemente mayor en PM (21,19 porciento), P. aurantiogriseum complex, se aisló en porcentajes menores del 1 porciento. El género Scopulariopsis fue escaso en PE, mientras en PM fue dominante (37,7 porciento) con la presencia de solo 2 especies (S. brevicaulis y S. koningii). El género Fusarium y los Mucorales fueron poco representados mientras las levaduras solo se destacaron en PE (10,27 porciento). Por el método, de siembra directa en agar agua, el género Aspergillus mantuvo una alta frecuencia, predominando al igual que en el método de dilución A. fumigatus y A. flavus. Entre la micota aislada, se detectaron hongos potencialmente toxicogénicos, los cuales podrían constituir un riesgo en salud, considerando que la pimienta es utilizada en la preservación y palatibilidad de los alimentos

Utilización de bacillus megaterium y bacillus thuringiensis para la detección de hongos toxicogénicos / Use of bacillus megaterium and bacillus thuringiensis for the detection of toxicogenic fungi

Se estudió la presencia de distintos hongos toxicogénicos frente a una cepa de Bacillus megaterium y Bacillus thuringiensis serotipo 1 mediante la técnica empleada por Basílico y col (1987). La actividad de las micotoxinas se expresó en función de los diámetros de las zonas de inhibición y mediante la medida de la longitud de las células bacterianas situadas en el borde de las mismas. La cepa de B. thuringiensis presentó mayores halos de inhibición frente a extractos conteniendo aflatoxinas, zearalenoma, ocratoxina, esterigmatocistina. También se observó inhibición frente a un extracto de Fusarium melanochlorum productor de toxina acetil T-2. Las mayores elongaciones celulares se obtuvieron con extractos conteniendo aflatoxinas, zearalenona y frente a un extracto de Aspergillus ochraceus productor de ocratoxina A. Con B. magaterium se obtuvieron halos menores o resultados negativos. Este microorganismo no presentó las elongaciones celulares características de B. thuringiensis serotipo 1

Studies on the Population of Toxigenic Fungi in Foodstuffs

These studies were carried out to detect the presence of mycotoxin producing fungi in various foodstuffs in Korea. The experiments were divided into three parts: bacteriologic, toxicologic and electron microscopic studies. From the 133 various samples, 425 colonies of fungi were isolated. In 405 of the 426 colonies it was possible to identify 17genera. Among the identified strains the predominant genera were Penicillum, Aspergillus and Alternaria. In the cytotoxicity test, 18 strains showed imld to severe toxic effects in mice, 19 strains showed toxic effects on HeLa cells. In electron microscopic studies of liver cells from aninals which had been treated with toxin-like substances, the liver cells showed the cytoplasmic changes dilatation of endoplasmic reticulum, swelling of mitochondria and increased number of lipid and glycogen particles. Alterations of nuclear envelape were also noted.