Determination of estrogenic mycotoxins in environmental water samples by low-toxicity dispersive liquid-liquid microextraction and liquid chromatography-tandem mass spectrometry

A novel, simple, rapid and eco-friendly method based on dispersive liquid-liquid microextraction using a bromosolvent was developed to determine six estrogenic mycotoxins (zearalenone, zearalanone, alpha-zearalanol, beta-zearalanol, alpha-zearalenol and beta-zearalenol) in water samples by liquid chromatography-electrospray ionization tandem mass spectrometry in the negative mode (LC-ESI-MS/MS). The optimal conditions for this method include the use of 100 mu L bromocyclohexane as an extraction solvent (using a non-dispersion solvent), 10 mL of aqueous sample (adjusted to pH 4), a vortex extraction time of 2 min, centrifugation for 10 min at 3500 rpm and no ionic strength adjustment. The calibration function was linear and was verified by applying the Mandel fitting test with a 95% confidence level. No matrix effect was observed. According to the relative standard deviations (RSDs), the precision was better than 13% for the repeatability and intermediate precision. The average recoveries of the spiked compounds ranged from 81 to 118%. The method limits of detection (LOD) and quantification (LOQ) considering a 125-fold pre-concentration step were 4-20 and 8-40 ng L-1, respectively. Next, the method was applied to the analysis of the environmental aqueous samples, demonstrating the presence of beta-zearalanol and zearalanone in the river water samples. (C) 2015 Elsevier B.V. All rights reserved.

Mycoflora and mycotoxins in field samples of Brazil nuts

Fungal and mycotoxin contamination was investigated in field samples of nuts, shells and pods of the Brazil nut collected during different periods in Itacoatiara, State of Amazonas, Brazil: 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. Aflatoxins and cyclopiazonic acid were not detected in any of the samples analyzed. The high frequency of isolation of aflatoxigenic A. flavus strains from soil and Brazil nuts increases the chance of aflatoxin production in these substrates. These findings suggest a possible contamination before drying and indicate soil as the main source of fungal contamination of Brazil nuts. (c) 2012 Elsevier Ltd. All rights reserved.

Mycobiota and mycotoxins in Brazil nut samples from different states of the Brazilian Amazon region

The objective of this study was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in Brazil nut samples collected in different states of the Brazilian Amazon region: Acre, Amazonas, Amapa, and Para. A total of 200 husk samples and 200 almond samples were inoculated onto Aspergillus flavus-parasiticus agar for the detection of fungi. Mycotoxins were analyzed by high-performance liquid chromatography. The mycobiota comprised the following fungi, in decreasing order of frequency: almonds - Phialemonium spp. (54%), Penicillium spp. (16%), Fusarium spp. (13%), Phaeoacremonium spp. (11%), and Aspergillus spp. (4%), husks - Phialemonium spp. (62%), Phaeoacremonium spp. (11%), Penicillium spp. (10%), Fusarium spp. (9%), and Aspergillus spp. A polyphasic approach was used for identification of Aspergillus species. Aflatoxins were detected in 22 (11%) of the 200 almond samples, with 21 samples presenting aflatoxin B-1 levels above 8 mu g/kg, the limit established by the European Commission for Brazil nuts for further processing. Nineteen (9.5%) of the 200 husk samples contained aflatoxins, but at levels lower than those seen in almonds. Cyclopiazonic acid (CPA) was detected in 44 (22%) almond samples, with levels ranging from 98.65 to 1612 mu g/kg. Aspergillus nomius and A. flavus were the most frequent Aspergillus species. The presence of fungi does not necessarily imply mycotoxin contamination, but almonds of the Brazil nut seem to be a good substrate for fungal growth. (C) 2012 Elsevier B.V. All rights reserved.

Monitoring and determination of fungi and mycotoxins in stored Brazil nuts

Brazil nut (Bertholletia excelsa) is an important commodity from the Brazilian Amazon, and approximately 37,000 tons (3.36 × 10⁷ kg) of Brazil nuts are harvested each year. However, substantial nut contamination by Aspergillus section Flavi occurs, with subsequent production of mycotoxins. In this context, the objective of the present investigation was to evaluate the presence of fungi and mycotoxins (aflatoxins and cyclopiazonic acid) in 110 stored samples of cultivated Brazil nut (55 samples of nuts and 55 samples of shells) collected monthly for 11 months in Itacoatiara, State of Amazonas, Brazil. The samples were inoculated in duplicate onto Aspergillus flavus and Aspergillus parasiticus agar and potato dextrose agar for the detection of fungi, and the presence of mycotoxins was determined by high-performance liquid chromatography. The most prevalent fungi in nuts and shells were Aspergillus spp., Fusarium spp., and Penicillium spp. A polyphasic approach was used for identification of Aspergillus species. Aflatoxins and cyclopiazonic acid were not detected in any of the samples analyzed. The low water activity of the substrate was a determinant factor for the presence of fungi and the absence of aflatoxin in Brazil nut samples. The high frequency of isolation of aflatoxigenic Aspergillus section Flavi strains, mainly A. flavus, and their persistence during storage increase the chances of aflatoxin production on these substrates and indicates the need for good management practices to prevent mycotoxin contamination in Brazil nuts.

Fumonisins and Alternaria alternata lycopersici toxins: sphinganine analog mycotoxins induce apoptosis in monkey kidney cells.

Fusarium moniliforme toxins (fumonisins) and Alternaria alternata lycopersici (AAL) toxins are members of a new class of sphinganine analog mycotoxins that occur widely in the food chain. These mycotoxins represent a serious threat to human and animal health, inducing both cell death and neoplastic events in mammals. The mechanisms by which this family of chemical congeners induce changes in cell homeostasis were investigated in African green monkey kidney cells (CV-1) by assessing the appearance of apoptosis, cell cycle regulation, and putative components of signal transduction pathways involved in apoptosis. Structurally, these mycotoxins resemble the sphingoid bases, sphingosine and sphinganine, that are reported to play critical roles in cell communication and signal transduction. The addition of fumonisin B1 or AAL toxin, TA, to CV-1 cells induced the stereotypical hallmarks of apoptosis, including the formation of DNA ladders, compaction of nuclear DNA, and the subsequent appearance of apoptotic bodies. Neither mycotoxin induced cell death, DNA ladders, or apoptotic bodies in CV-1 cells expressing simian virus 40 large T antigen (COS-7) at toxin concentrations that readily killed CV-1 cells. Fumonisin B1 induced cell cycle arrest in the G1 phase in CV-1 cells but not in COS-7 cells. AAL toxin TA did not arrest cell cycle progression in either cell line. The induction of apoptosis combined with the widespread presence of these compounds in food crops and animal feed identifies a previously unrecognized health risk to humans and livestock. These molecules also represent a new class of natural toxicants that can be used as model compounds to further characterize the molecular and biochemical pathways leading to apoptosis.

Mycotoxins and abnormal embryonic development

This chapter reviews studies on the effects of mycotoxins on embryonic and fetal development, especially those toxins that are global food and feed contaminants. The toxins discussed include aflatoxin produced by Aspergillus flavus and A. parasiticus, ochratoxin which is produced by Aspergillus species particularly A. ochraceus as well as Penicillium verrucosum, ergot alkaloids produced by Claviceps spp., and the Fusarium toxins (fumonisins, deoxynivalenol [vomitoxin], and zearalenone). These toxins have been shown to be teratogenic and/or embryotoxic in different animal bioassays. The implications of toxicity on embryogenesis, and the progress of research on these mycotoxins, are also examined.

An in vitro investigation on the cytotoxic and nuclear receptor transcriptional activity of the mycotoxins fumonisin B1 and beauvericin

Fumonisin B1 (FB1) and beauvericin (BEA) are secondary metabolites of filamentous fungi, which under appropriate temperature and humidity conditions may develop on various foods and feeds. To date few studies have been performed to evaluate the toxicological and endocrine disrupting effects of FB1 and BEA. The present study makes use of various in vitro bioassays including; oestrogen, androgen, progestagen and glucocorticoid reporter gene assays (RGAs) for the study of nuclear receptor transcriptional activity, the thiazolyl blue tetrazolium bromide (MTT) assay to monitor cytotoxicity and high content analysis (HCA) for the detection of pre-lethal toxicity in the RGA and Caco-2 human colon adenocarcinoma cells. At the receptor level, 0.001-10μM BEA or FB1 did not induce any agonist responses in the RGAs. However at non-cytotoxic concentrations, an antagonistic effect was exhibited by FB1 on the androgen nuclear receptor transcriptional activity at 10μM and BEA on the progestagen and glucocorticoid receptors at 1μM. MTT analysis showed no decrease in cell viability at any concentration of FB1, whereas BEA showed a significant decrease in viability at 10μM. HCA analysis confirmed that the reduction in the progestagen receptor transcriptional activity at 1μM BEA was not due to pre-lethal toxicity. In addition, BEA (10μM) induced significant toxicity in both the TM-Luc (progestagen responsive) and Caco-2 cells.

Co-exposure to mycotoxins: the case of waste management workers

Introduction - Occupational exposures are characterized by being complex and associated to co-exposure to several contaminants by different exposure routes. Even if exposure occurs to only a chemical agent, it can have different exposure routes and can result in different health effects. The waste management setting is recognized by the presence of several chemical and biologic agents in the workplaces. Recently, it was reported occupational exposure to Aflatoxin B1 (AFB1) in one Portuguese waste management industry. However, data regarding to fungal burden showed that exposure to other mycotoxins should be expected. Aim of the study - The aim of the present work was to know if workers from this waste management industry were exposed to other mycotoxins besides AFB1.

Climate changes influence in occupational exposure to fungi and mycotoxins

Climate changes and their effects on fungal distribution and activity are aspects of concern regarding the human exposure to mycotoxins. An exhaustive search was made for papers available in scientific databases reposrting the influence that climate cchange has on fungi and mycotoxins. Also a review regarding fungal burden, collected between 2010 and 2015 in different settings, was done to support the discussion about future fungi and mycotoxins ocuupational exposure. A. flavus complex, E. graminerarum complex and F. verticilliodes were the most reported to be influenced by climate changes. We noted also that the analyzed Portuguese settings presented already an occupational problem due to their fungal burden. It will be important to know future climate changes to select what complexes/species and strains, and consequently the mycotoxins, we should consider as indicators of an occupational problem. In addition, epidemiologic studies are needed to increase knowledge about potential health effects related with the exposure to both risk factors.

Survey of veterinery drug residues, environmental contaminants and mycotoxins of cultured shirmp in Iran

Economical achievement of optimal growth in developing countries may lead to sustainable poverty reduction. Agricultural activities play an important role in economy and human being welfare, which leads to establishment of food security and quality. Aquaculture products in developing countries share 51.4 percent of total agricultural production and 241 percent in developed countries. Therefore undoubtedly food production by means of quality and quantity has to be increased .The history of shrimp production goes back to 500 years ago. Today 50 countries of the world produce shrimp. In Islamic Republic of Iran shrimp production started since 1992 in the coastal region of Persian Gulf. The shrimp culture farms can be classified in to 4 different categories; extensive, semi-extensive, intensive and super intensive. Global ecological maintenance is one of the major concerns of authorities Human manipulation of nature is the most destructive activity. Industrial sewage leakage in to the rivers and water sources is a big issue that causes reduction in the aquatic population. Heavy metals have an inhibitory effect in the production and growth of sea life. Human intake of food treated with anti-microbial cause's allergy, hypersensitivity and develops microbial resistance. Organochlorine compounds contamination may found in hepatopancreatic tissue of aquatic products, Arsenic may transfer to man via plant and animal product contamination.