Mutual effects on mycotoxin production during co-culture of ochratoxigenic and aflatoxigenic Aspergillus strains
AbstractMycotoxin co-occurrence compromises the safety of food crops worldwide. Environmental factors, as well as fungal interaction, can substantially influence the infectivity of mycotoxigenic fungi and their subsequent production of multi-mycotoxin. Here, we investigated the mutual effects of the co-culture of ochratoxigenic and aflatoxigenicAspergillus strains on the co-production of ochratoxin A (OTA) and aflatoxin B1 (AFB1). Single cultures of ochratoxigenicA. carbonarius andA. alliaceus grew optimally at 25 °C, whereas aflatoxigenicA. flavus grew optimally at 35 °C. The maximum levels of OTA and AFB1 were achi...
Source: Mycotoxin Research - January 12, 2023 Category: Toxicology Source Type: research
Zearalenone and its metabolite exposure directs oestrogen metabolism towards potentially carcinogenic metabolites in human breast cancer MCF-7 cells
In this study, the effects of ZEN and its metabolites α-zearalenol (α-ZEL), and β-zearalenol (β-ZEL) on the formation of carcinogenic oestrogen-catechols in MCF-7 cells were investigated. To assess the effects of mycoestrogens on the activity of cytochrome P450 1A1 and CYP1B1, the rate of ethoxyresorufin O-deethylation (EROD-assay) was measured. Th e effects of mycoestrogens on the expression of CYP 1A1, CYP 1B1, aryl-hydrocarbon receptor (AhR), and oestrogen receptor alpha (ERα) were determined by qPCR. The catechol-O-methyltransferase (COMT) activity was measured as the ratio of the methoxy metabolites of oestradiol...
Source: Mycotoxin Research - December 15, 2022 Category: Toxicology Source Type: research
Micro-climatic variations across Malawi have a greater influence on contamination of maize with aflatoxins than with fumonisins
This study reports levels of aflatoxin and fumonisin in maize samples (n = 1294) from all agroecological zones (AEZs) in Malawi. Most maize samples (> 75%) were contaminated with aflatoxins and 45% with fumonisins, which co-occurred in 38% of the samples. Total aflatoxins varied across the AEZs, according to mean annual temperature (P < 0.05) of the AEZs. Samples from the lower Shire AEZ (median = 20.8 µg/kg) had higher levels of aflatoxins (P < 0.05) than those from the other AEZs (median = 3.0 µg/kg). Additionally, the majority (75%) of the positive samples from the lower Shire AEZ h...
Source: Mycotoxin Research - November 29, 2022 Category: Toxicology Source Type: research
Infected grasses as inoculum for Fusarium infestation and mycotoxin accumulation in wheat with and without irrigation
AbstractGrasses growing next to agricultural fields influence theFusarium abundance, the species composition, and the mycotoxin accumulation of wheat plants, especially the field parts directly adjacent to grasses, are highly affected. Grasses are a more attractive and suitable habitat forFusarium fungi compared to other arable weeds and occur at mostly every semi-natural landscape element (e.g., kettle holes, hedgerows, field-to-field-borders). In our study, we analyzed the ability of a highlyFusarium infected grass stripe (F. graminearum,F. culmorum,F. sporotrichioides) to infect an adjacent wheat field with these specie...
Source: Mycotoxin Research - October 25, 2022 Category: Toxicology Source Type: research
Temporal and spatial dynamics of Fusarium spp. and mycotoxins in Swedish cereals during 16 years
AbstractWe analysed the dynamics ofFusarium spp. and mycotoxin contamination in Swedish cereals during 2004 –2018. More than 1400 cereal samples from field trials were included, collected in a monitoring programme run by the Swedish Board of Agriculture. FiveFusarium mycotoxins were quantified with LC-MS/MS and fungal DNA from four species was quantified using quantitative real-time PCR. Correlation analyses revealed that deoxynivalenol (DON) and zearalenone (ZEN) were mainly associated withFusarium graminearum, but stronger correlations withF.culmorum was seen some years. Nivalenol (NIV) was associated withF.poae and th...
Source: Mycotoxin Research - October 24, 2022 Category: Toxicology Source Type: research
Harvest and post-harvest handling practices associated with fumonisin B1 contamination in maize (Zea mays L.): dietary exposure and risk characterization in eastern Ethiopia
This study aimed to assess post-harvest handling and awareness against fungal development and fumonisin B1 (FB1) in maize and to calculate risk exposures of FB1. A total of 197 maize samples (grain and flour) were collected from five districts (Haramaya, Kersa, Meta, Oda Bultum, and Tullo). FB1 was detected using LC –MS/MS qTRAP. Exposure assessment was done based on the maize consumption rate per day in Ethiopia for different age groups (infants, children, and adults). Risk characterization depends on the margin of exposure (MoE) combined with the lower confidence limit of the benchmark dose level (BMDL). Ab out 81% of ...
Source: Mycotoxin Research - September 30, 2022 Category: Toxicology Source Type: research
Enzyme immunoassays for the detection of mycotoxins in plant-based milk alternatives: pitfalls and limitations
This study investigated the applicability of enzyme immunoassay (EIA) methods for direct testing of PBMAs without sample extraction. Mycotoxin analyses included aflatoxin B1 (AFB1), sterigmatocystin (STC), ochratoxin A (OTA), deoxynivalenol (DON), and T-2/HT-2-toxin (T-2/HT-2). It was found that the PBMA matrix negatively affected the EIA to varying degrees, thus affecting the reliability of the results. A dilution of PBMAs of at least 1:8 was necessary to overcome matrix interference. This resulted in calculated detection limits of 0.4 µg/L (AFB1), 2 µg/L (STC), 0.08 µg/L (OTA), 16 µg/L (DON), and 0.4 µg/L (T-...
Source: Mycotoxin Research - September 2, 2022 Category: Toxicology Source Type: research
Combined effects of cadmium and ochratoxin A on intestinal barrier dysfunction in human Caco-2 cells and pig small intestinal epithelial cells
AbstractHazardous chemicals are commonly found in cereals and cereal-based products. However, most studies focus on the individual effects of these mycotoxins or metals, rather than their combined toxicity. The main objective of this study was to evaluate the combined effects of cadmium (Cd) and ochratoxin A (OTA) on intestinal barrier integrity using Caco-2 cells and pig small intestinal epithelial (PSI) cells as models of intestinal epithelial cells and to measure alterations in cell survival and barrier integrity. The combined effects on cell viability were assessed in terms of a combination of index values. These findi...
Source: Mycotoxin Research - August 5, 2022 Category: Toxicology Source Type: research
Mycotoxin levels and characterization of natural anti-fungal phytochemicals in pearl millet (Pennisetum glaucum) from Nigeria ’s six agroecological zones
This study reports levels of multiple mycotoxins across Nigeria ’s six agro-ecological zones and corresponding levels of natural anti-fungal phytochemicals present in pearl millet (PM). 220 representative composite samples of PM were collected for mycotoxin analysis using ultrahigh performance liquid chromatography-mass spectrometry (UHPLC-MS), and 24 were ran domly selected for determination of metabolites using gas chromatography-high resolution time of flight-mass spectrometry (GC-HRTOF-MS). In total, 15 mycotoxins were detected, all with levels below the European Union (EU) permissible limits and level of aflatoxins ...
Source: Mycotoxin Research - August 3, 2022 Category: Toxicology Source Type: research
General toxicity and genotoxicity of alternariol: a novel 28-day multi-endpoint assessment in male Sprague –Dawley rats
This study used a novel in vivo 28-day multi-endpoint (Pig-a assay + micronucleus test + comet assay) genotoxicity evaluation system to evaluate the general toxicity and genotoxicity of AOH. A total of 42 male Sprague–Dawley rats were randomly distributed into three AOH-treated groups (5.51, 10.03, and 22.05 µg/kg bw), one AOH high-dose recovery group (AOH-HR, 22.05 µg/kg bw), one positive control group (N-ethyl-N-nitrosourea, 40 mg/kg bw), and two vehicle control groups (corn oil and PBS). Treatments were administered by oral gavage for 28 consecutive days. Histopathological lesions were observed in the li...
Source: Mycotoxin Research - August 1, 2022 Category: Toxicology Source Type: research
Analysis of mold and mycotoxins in naturally infested indoor building materials
AbstractHealth issues of residents of mold-infested housing are reported on a regular basis, and reasons for the arising impairments can be manifold. One possible cause are the toxic secondary metabolite produced by indoor microfungi (mycotoxins). To enable a more thorough characterization of the exposure to mycotoxins in indoor environments, data on occurrence and quantities of mycotoxins is essential. In the presented study, 51 naturally mold-infested building material samples were analyzed applying a previously developed method based on ultra-high performance liquid chromatography (UHPLC) separation in combination with ...
Source: Mycotoxin Research - July 28, 2022 Category: Toxicology Source Type: research
LaeA regulates morphological development and ochratoxin A biosynthesis in Aspergillus niger
AbstractThe global regulator LaeA and its orthologs govern the morphogenetic development and secondary metabolism of several filamentous ascomycetes. InAspergillus niger, it has been shown that an LaeA ortholog (AnLaeA) regulates the production of citric acid and secondary metabolites. In this work, we constructedAnlaeA disruption and overexpression strains to investigate the roles of AnLaeA in morphological development and ochratoxin A (OTA) biosynthesis inA. niger. Phenotypic observation, chemical analysis, and gene expression analysis indicated that AnLaeA acts as a negative regulator of conidial morphogenesis and posit...
Source: Mycotoxin Research - July 26, 2022 Category: Toxicology Source Type: research
From the laboratory bench to the lecture hall: latest findings from mycotoxin research presented at the 43rd Mycotoxin Workshop
(Source: Mycotoxin Research)
Source: Mycotoxin Research - July 15, 2022 Category: Toxicology Source Type: research
Analysis of aflatoxins and ochratoxin a in chilli powder using ultrahigh performance liquid chromatography with fluorescence detection and tandem mass spectrometry
AbstractChilli powder, a popular spice, is predominantly contaminated with aflatoxins (AFs) and ochratoxin A (OTA), posing a menace to public health. As no validated method exists for the simultaneous and direct analysis of AFs and OTA in chilli powder, it was imperative to develop one to ensure their effective monitoring and promote trade. In this research, we developed and validated a multi-mycotoxin analysis method that allows the simultaneous determination of AFs (AFB1, AFB2, AFG1 and AFG2) and OTA in chilli powder with high sensitivity, accuracy and precision. The optimised sample preparation workflow started with the...
Source: Mycotoxin Research - July 14, 2022 Category: Toxicology Source Type: research
A preliminary study on aflatoxin exposure by urine biomonitoring in Chile
AbstractWe assessed the occurrence of aflatoxin M1 (AFM1) in urine in a sample of the MAUCO population-based cohort (n = 120) using an enzyme-linked immune sorbent assay (ELISA) kit specially designed for the analysis of AFM1 in urine. We found AFM1 in the urine of 59% of the participants (> limit of detection), with 12% of the samples being over the limit of quantification. The mean of the quantifiable samples was 0.66 (± 0.35) ng/mg adjusted creatinine, ranging from 0.31 to 1.39 ng/mg creatinine. The mean probable daily intake (PDI) of AFB1 was 0.23 ( ± 0.37) ng/kg bw according to the upper bound (UB), b...
Source: Mycotoxin Research - May 31, 2022 Category: Toxicology Source Type: research
