Mycotoxin Research最新文献

The fungal genus Fusarium contains many toxigenic pathogens of maize with associated yield losses, reduction of grain quality, and accumulation of mycotoxins in harvested grains. To determine zearalenone (ZEN) concentration and identify the various Fusarium species in commercial maize grains, a survey of 75 maize samples, collected from 11 market centers in the five regions in northern Ghana was identified based on morphological characteristics, sequence analysis of the internal transcribed spacer region, and polymerase chain reaction using species-specific primers. ZEN levels were determined using HPLC. ZEN contamination was recorded in 33.3% of the maize samples, with concentrations ranging from 0.61 to 3.05 µg/kg. Based on VERT1/2 and TEF 1-α sequencing, F. verticillioides was the most prevalent species in the studied samples: 40.35% from the Upper East Region, 28.07% from the North East Region, 19.30% from the Upper West Region, 10.53% from the Savannah Region, and 1.75% for the Northern Region. Other fungal species found were F. equiseti and F. solani. A higher number of the Fusarium isolates were found in white maize (609 isolates from 27 samples) compared to yellow maize (225 isolates from 23 samples).

Environmental factors influence fungal growth and mycotoxin production in stored grains. However, the concentrations of free mycotoxins and their conjugates and how they are impacted by different interacting environment conditions have not been previously examined. The objectives of this study were to examine the impact of storage conditions (0.93-0.98 a_w) and temperature (20-25 °C) on (a) the concentrations of deoxynivalenol and zearalenone and their respective glucosides/conjugates and (b) the concentrations of emerging mycotoxins in both naturally contaminated and irradiated wheat grains inoculated with Fusarium graminearum. Contaminated samples were analysed for multiple mycotoxins using Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Method validation was performed according to the acceptable performance criteria set and updated by the European Commission regulations No. 2021/808/EC. As an important conjugate of deoxynivalenol, the concentrations of deoxynivalenol-3-glucoside were significantly different from its precursor deoxynivalenol at 0.93 a_w (22% moisture content- MC) at 25 °C in the naturally contaminated wheat with a ratio proportion of 56:44% respectively. The high concentrations of deoxynivalenol-3-glucoside could be influenced by the wheat's variety and/or harvested season/fungal strain type/location. Zeralenone-14-sulfate concentrations were surprisingly three times higher than Zearalenone in the naturally contaminated wheat at 0.98 a_w (26% MC) at both temperatures. Emerging mycotoxins such as moniliformin increased with temperature rise with the highest concentrations at 0.95 a_w and 25 °C. These findings highlight the influence and importance of storage a_w x temperature conditions on the relative presence of free vs conjugated mycotoxins which can have implications for food safety.

The occurrence of Ochratoxin A (OTA) in wine is commonly known, but there is only limited information about its occurrence in grape mash and wines of German origin. Climate change has led to higher temperatures in the southern regions of Germany, which may increase the growth of fungi associated with the production of OTA and increase the content of this mycotoxin in grapes. A safe and rapid UHPLC-FLD method was developed and validated to assess the contamination of grape mash and wine with OTA. A total of 71 samples of grape mash and 30 wines from various wine producers in Baden-Württemberg, Germany, were analysed for OTA content. The results showed that no samples contained OTA in concentrations above the limit of detection. Further monitoring of samples from different vintages is needed.

Maize (Zea mays L.) is an important cereal crop worldwide. Contaminated maize kernels pose a significant mycotoxin exposure risk for humans in Latin America. Fumonisins, the most prevalent mycotoxin in maize, typically occur during pre-harvest conditions leading to significant economic losses. Various factors, including weather conditions, may influence this contamination. This study aimed to determine the association between fumonisin B₁ (FB₁) contamination, prevalence of Fusarium verticillioides, weather conditions and kernel quality in the two primary maize production areas in Costa Rica (Brunca and Chorotega). All maize samples (100%) showed FB₁ contamination, with higher concentrations in samples from Brunca region, consistent with the presence of F. verticilliodes. Weather conditions appeared to play an important role in this contamination, since Brunca region had the highest mean temperature and relative humidity after maize silking (R1) and the total monthly rainfall in this region was significantly higher during the last two months of maize cultivation (grain-filling and physiological maturity stages R3 to R6). Interestingly, this study found a negative correlation between grain damage and kernel contamination with FB₁ and F. verticillioides. The concentration of mineral nutrients in kernels from both regions was largely similar. Most nutrients in kernels exhibited a negative correlation with FB₁, particularly nitrogen. Zinc and phosphorus were the only nutrients in kernels showing a positive correlation with FB₁ in samples from the Brunca region. The results highlight elevated levels of FB₁ contamination in maize and contribute to a better understanding of pre-harvest factors influencing FB₁ contamination in tropical conditions.

Throughout history, Turkish coffee has been the most widely consumed type of coffee in Turkey. Therefore, the goal of this study was to determine the amount of ochratoxin A (OTA) present in Turkish coffee and to analyze any potential health hazards. A total of 41 Turkish coffees were collected and analyzed for OTA activity using a competitive enzyme immunoassay (ELISA). Furthermore, dietary exposure and health risk assessments for the Turkish population were calculated based on analytical results and coffee consumption data from the Turkish Nutrition and Health Survey 2019 (TNHS-2019) in three age categories (15-18, 19-64, and 65 + years). Nine of the samples contained more than 2.5 μg/kg OTA, with an average of 5.24 μg/kg. The OTA concentration in 3 samples exceeded the permissible maximum limit (5 μg/kg) established by Turkish legislation, and the mean concentration was 8.41 μg/kg. A margin of exposure (MOE) approach was used for risk characterization, considering both non-neoplastic and neoplastic consequences. There were no concerns about health risks because MOEs were more than 10,000 for all categories. Although the levels of OTA analyzed in Turkish coffee did not pose a risk to individuals in the three age categories, emphasis should be placed on minimizing and controlling OTA concentrations in Turkish coffee. Additionally, it is also necessary to consider other food sources that could contribute to OTA exposure.

Mycotoxins are secondary metabolites produced by fungi with harmful effects such as carcinogenicity, teratogenicity, nephrotoxicity, and hepatotoxicity. They cause widespread contamination of plant products such as crops, food, and feed, posing serious threats to the life and health of human beings and animals. It has been found that many traditionally synthesized and natural compounds are capable of inhibiting the growth of fungi and their secondary metabolite production. Natural compounds have attracted much attention due to their safety, environmental, and health friendly features. In this paper, compounds of plant origin with inhibitory effects on ochratoxins, aflatoxins, Fusarium toxins, and Alternaria toxins, including cinnamaldehyde, citral, magnolol, eugenol, pterostilbene, curcumin, and phenolic acid, are reviewed, and the inhibitory mechanisms of different compounds on the toxin production of fungi are also elucidated, with the aim of providing application references to reduce the contamination of fungal toxins, thus safeguarding the health of human beings and animals.

Yogurt, a milk-derived product, is susceptible to mycotoxin contamination. While various methods have been developed for the analysis of dairy products, only a few have been specifically validated for yogurt. In addition, these methods are primarily focus on detecting aflatoxins and zearalenone. This study aimed to conduct a preliminary investigation into the presence of regulated, emerging, and modified mycotoxins in natural and oat yogurts available in the Spanish market. For this, a QuEChERS-based extraction method was optimized and then validated to detect and quantify 32 mycotoxins using ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS). The method was in-house validated for the analysis of natural and oat yogurt in terms of linearity, matrix effect, sensitivity, accuracy, and precision. Satisfactory performance characteristics were achieved; for most of the analytes, LOQs were lower than 2 ng/g, and recoveries ranged from 60 to 110% with a precision, expressed as the relative standard deviation of the recovery, lower than 15%. Subsequently, the validated method was applied to analyze commercial yogurt samples, revealing a notable incidence of beauvericin and enniatins, with some analogues found in up to 100% of the samples. Alternariol methyl ether was also frequently found, appearing in 50% of the samples. Additionally, the study identified regulated toxins such as fumonisins, ochratoxin A , and HT-2 toxin. These results provide new incidence data in yogurt, raising concerns about potential health risks for consumers.

Aflatoxin B1 (AFB1) is among the most potent genotoxic and carcinogenic mycotoxins and is a major source of distress for the growing poultry sector. On the other hand, distillery yeast sludge or distillery sludge (DS) is a byproduct of molasses-based industries. It is often treated as a waste despite containing abundant nutrients particularly protein, basic amino acids, and vitamins along with other macro and micronutrients. This study was designed to investigate the oxidative stress and immunological alterations induced by AFB1 and their amelioration by dietary supplementation with DS. For this purpose, 360 newly hatched broiler chicks were randomly divided into twelve groups (30 birds each) and fed different combinations of AFB1 (100, 200, or 600 µg/kg) and DS (5 or 10 g/kg) for 42 days. The parameters under consideration were body weight, feed conversion ratio (FCR), relative organ weights, histopathological examination of different visceral organs, total antioxidant capacity, antibody response to intravenous injection of sheep red blood cells, in situ lymphoproliferative response to phytohemagglutinin-P, and phagocytic potential through a carbon clearance assay system. The results of this study established that DS supplementation ameliorated AFB1-associated oxidative stress and ameliorated toxicopathological and immunological anomalies in groups given AFB1 at 100 µg/kg and 200 µg/kg; however, little to no relief was observed in birds fed AFB1 at 600 µg/kg. The determination of the actual ratio of the AFB1 to the DS for substantiating the ameliorating effects requires further investigation.

Citrinin (CIT) is a nephrotoxic mycotoxin, produced by several species of Penicillium, Aspergillus, and Monascus. The foodstuffs most frequently contaminated with CIT include cereals, cereal products, and red yeast rice. Studies on the occurrence of CIT in food have shown that the CIT concentrations in processed cereal-based products are generally lower than in unprocessed industry cereal samples. One possible explanation is the reaction of CIT with major food components such as carbohydrates or proteins to form modified CIT. Such modified forms of CIT are then hidden from conventional analyses, but it is possible that they are converted back into the parent mycotoxin during digestion. The aim of this study is therefore to investigate reactions of CIT with food matrix during thermal processes and to gain a deeper understanding of the degradation of CIT during food processing. In this study, we could demonstrate that CIT reacts with amino compounds such as proteins, under typical food processing conditions, leading to modified forms of CIT.

This study investigated the occurrence and distribution of multiple mycotoxins (aflatoxin B₁, B₂, G₁, G₂, fumonisins B₁, B₂, ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEN), and citrinin (CIT)) in cassava products and as assessed the potential risk of aflatoxin B1 (AFB₁) exposure among cassava consumers. A total of 192 samples of cassava products (96 flour and 96 chips, each with 48 samples from farmer and 48 from wholesaler) were analysed using LC/MS–MS. All positive samples irrespective of their origin (flour or chips) exhibited AFB₁ levels exceeding the EU regulatory threshold of 5 µg/kg. The sum of fumonisins (FB₁ + FB₂), ZEN, and DON were significantly (P < 0.05) higher in cassava flour (14.3 µg/kg; 3.71 µg/kg; 25.1 µg/kg) compared to chips (6.54 µg/kg; 1.25 µg/kg; 0.25 µg/kg), respectively. Aflatoxins G₂ was not detected in any of 192 samples. Cassava flour samples from farmers exhibited significantly (P < 0.05) higher mean concentrations of AFB₁ (27.1 µg/kg), total aflatoxins (78.2 µg/kg), and ochratoxin A (79.6 µg/kg) in contrast to wholesalers, whose mean levels were notably lower at 8.91, 5.79 µg/kg, and 2.44 µg/kg, respectively, pointing the likely critical source of mycotoxin contamination. Cassava consumers in Northern Uganda are at a higher risk, with an estimated 2.06 cancer cases per 100,000 individuals per year compared to those in Eastern Uganda at 0.25. This study underscores the urgent need for interventions to manage aflatoxins in cassava flour, particularly at farm level in Northern Uganda. It accentuates a shift market to household-level sampling and the need for analytical methods targeting multiple mycotoxins.