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Ochratoxin A (OTA) is a mycotoxin with nephrotoxic, genotoxic, teratogenic and carcinogenic properties, produced by several species of Aspergillus, mainly those belonging to the A. section Circumdati and A. section Nigri. Although this toxin has been detected in spices and condiments, in black pepper (Piper nigrum L.) few studies have investigated the mycobiota (based on a molecular approach) and the presence of OTA in this food. The aim of this study was to investigate the presence of potentially ochratoxigenic species and ochratoxin A in black pepper marketed in Brazil, one of the largest producers in the world. A total of 60 samples of black pepper (29 in powder and 31 in grain) were collected in markets. The presence of OTA was investigated in black pepper samples using High-Performance Liquid Chromatography (HPLC), OTA was detected in 55% of the samples, with levels ranging from 0.05 to 13.15 µg/kg, all of which were below the Brazilian legal tolerances. A. section Nigri and A. section Circumdati were found in 80% of the samples, but the species of A. section Nigri were significantly more frequent than those of A. section Circumdati. The potential for OTA production by fungal isolates was tested using the agar plug technique and confirmed by HPLC. Among the isolates belonging to A. section Nigri (n = 1,083) and A. section Circumdati (n = 129), 3.7% and 3.8%, respectively, were able to produce OTA in Yeast Extract Sucrose Agar (YESA). A total of 25 strains from A. section Circumdati and 64 from A. section Nigri were identified using molecular data. The following potentially ochratoxigenic species were found in black pepper: A. niger, A. welwitschiae, A. carbonarius, A. westerdijkiae and A. ochraceus. The occurrence of these species denotes the need for continuous monitoring of black pepper by regulatory bodies in order to safeguard consumers' health.

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Although Aspergillus flavus and Aspergillus parasiticus are the main microorganisms of concern in peanuts, due to aflatoxin contamination, several Salmonella outbreaks from this product have been reported over the last ten decades. Thus, it is important to understand the relationship between microorganisms to predict, manage and estimate the diversity in the peanut supply chain. The purpose of this study was to evaluate aflatoxin production during the co-cultivation of Aspergillus section Flavi and Salmonella both isolated from peanuts. Three strains of A. section Flavi: A. flavus producing aflatoxin B, A. flavus non-producing aflatoxin and A. parasiticus producing aflatoxin B and G were co-cultivated with seven serotypes of Salmonella of which six were isolated from the peanut supply chain (S. Muenster, S. Miami, S. Glostrup, S. Javiana, S. Oranienburg and S. Yoruba) and one was S. Typhimurium ATCC 14028. First of all, each Salmonella strain was inoculated by pour plate (ca. 5 log cfu/mL) in PDA (potato dextrose agar). Then, each pre-cultured fungus was inoculated in the center of the petri dish. The plates were incubated at 30 °C and the fungal colony diameter was measured once a day for 7 days. As a control each Aspergillus strain was cultivated in the absence of Salmonella culture. All three strains of Aspergillus with absence of Salmonella (control) reached the maximum colony diameter and their growth rate was influenced when co-cultivated (p < 0.05) with all Salmonella serotypes tested. The maximum inhibition in the colony diameter was 20% for A. flavus aflatoxin B producer and A. parasiticus, and 18% for A. flavus non- aflatoxin producer when cultivated with Salmonella. However, no significant difference (p < 0.05) in reduction of colony diameter was observed among the Salmonella serotypes. Aflatoxin production was determined previously, by using the agar plug technique on thin layer chromatography (TLC). The production of aflatoxin G by A. parasiticus in co-cultivation with Salmonella was not observed. On the other hand, A. flavus preserved their characteristics of aflatoxin B production. The quantification of aflatoxin reduction by Salmonella interaction was evaluated using HPLC method. There was a maximum reduction of aflatoxin production of 88.7% and 72.9% in A. flavus and A. parasiticus, respectively, when cultivated with Salmonella. These results indicate that some serotypes of Salmonella may interfere with aflatoxin production and fungal growth of A. flavus and A. parasiticus in the peanut supply chain.

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A total of 119 samples of peanut were collected throughout the peanut production chain in São Paulo State, Brazil. The peanut samples were directly plated for determination of percentages of infection and a polyphasic approach was used to identify Aspergillus section Flavi species. Further, the potential for aflatoxin production by the isolates was tested using the agar plug technique and the presence of aflatoxins in peanuts was assessed using an immunoaffinity column followed by quantification using HPLC with reverse phase column and fluorescence detection. The limit of detection and quantification were 0.05 and 0.17µg/kg for total aflatoxins, respectively. Four species of Aspergillus section Flavi were isolated: A. caelatus (11), A. flavus (515), A. parasiticus (17) and A. tamarii (13). All isolates of A. parasiticus were able to produce aflatoxin B and G whereas aflatoxin B was produced by 50% of A. flavus isolates. Aflatoxins were found in 12 samples at concentrations ranging from 0.3 to 100µg/kg. The data reported in this study add information on the occurrence and biodiversity of fungi in peanuts at several stages of the production chain. The occurrence of aflatoxins is also of major relevance for continuous monitoring and assessment of likely exposure of consumers to aflatoxins through consumption of peanuts.

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O trigo é um dos alimentos mais consumidos na dieta humana, contribuindo com cerca de 20 % das calorias diárias. Considerando a predominância de Fusarium graminearum neste grão, a contaminação por desoxinivalenol (DON) foi avaliada em trigo dos Estados do Paraná (21 amostras) e do Rio Grande do Sul (15 amostras), assim como se estimou o risco da sua ingestão diária no município de Londrina-PR, Brasil. Utilizando Cromatografia Líquida de Alta Eficiência (CLAE), DON foi detectado em 72,2 % das amostras, variando de não detectável a 1592,21 µg/kg, nível médio 321,59 µg/kg (limite de quantificação= 87,75 µg/kg). Para calcular a Ingestão Diária Estimada (IDE) de DON foi aplicado Questionário de Freqüência de Consumo de Alimentos a 260 indivíduos (8-76 anos, 64,8 % do gênero feminino e 35,2 % do masculino). Os derivados mais consumidos foram massas alimentícias (151 g/semana) e pão francês (267 g/semana). Baseado nesses alimentos, a IDE média de DON foi de 0,308 µg/kg peso corporal/dia, sendo que dois indivíduos (0,8 %) apresentaram IDE superior a Ingestão Diária Máxima Tolerável Provisória (IDMTP) recomendada de 1 µg/kg p.c./dia. A importância de contínuo monitoramento perante perigo de exposição a DON é evidente, sendo que os níveis máximos em trigo no Brasil foram recentemente publicados pela ANVISA.

Wheat comprises one of the main ingredients in human diet, accounting for approximately 20 % of daily calories. Concerning the predominant frequency of deoxynivalenol (DON) producing Fusarium graminearum in wheat, DON occurrence in the State of Paraná (21 samples) and Rio Grande do Sul (15 samples), as well as the risk assessment of daily intake of DON in Londrina-PR, Brazil were evaluated. DON was detected in 72.2 % samples by high performance liquid chromatography (HPLC), which ranged from non-detectable to 1,592.21 µg/kg, with average of 321.59 µg/kg (limit of quantification= 87.75 µg/ kg). In order to calculate the estimated daily intake (EDI) of DON, a Food Frequency Questionnaire was applied to 260 persons (64.8 % female and 35.2 % male, from 8 to 76 years-old). The main food ingested were pasta (151 g/week) and bread (267 g/week), and based in these items, the average estimated daily intake (EDI) of DON was 0.308 µg/kg body weight/day. This EDI was lower than Provisional Tolerable Daily Maximum Intake (PTDMI) settled in 1 µg/kg b.w./day, although two persons showed estimated DON ingestion above PTDMI. The data ratify the importance of continuous monitoring and risk assessment targeted on DON exposure.

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