Reactive oxygen species involvement in apoptosis and mitochondrial damage in Caco-2 cells induced by enniatins A, A₁, B and B₁

Occurrence of Fusarium species and mycotoxins in wheat grain collected in the Czech Republic

Random collections of ears of winter wheat cultivars grown within the Czech Republic were made during 2004-2013. The ears were assessed for Fusarium head blight symptoms on a 0-9 scale and grain samples were analysed for deoxynivalenol (DON) content by enzyme-linked immunosorbent assay. Samples from 2011-2013 were analysed in greater detail, including to detect Fusarium species using polymerase chain reaction assays and determine mycotoxin content (including ‘emerging’ mycotoxins) using ultra-high performance liquid chromatography coupled with tandem mass spectrometry. The 10-year survey reveals a significant adverse effect from maize as the preceding crop on the accumulation of DON. Most endangered were those areas situated in the eastern part of the country. The study revealed prevailing occurrence of Fusarium poae and Fusarium graminearum within the Czech Republic. The occurrence of F. poae increased greatly in 2012 (with 93.3% of samples infected) in association with relatively warmer and drier weather. These investigations provide abundant evidence as to the presence of so-called ‘emerging’ mycotoxins, particularly enniatins. The survey also shows that increased content of ‘emerging’ mycotoxins could be accompanied by high DON content through mixed infections. Among examined toxins, only DON and DON-3-glucoside (DON-3G) were positively correlated (r=0.800; P<0.001) while levels of the remaining toxins were independent of one another. DON production by both DON-producing species F. graminearum and Fusarium culmorum was significantly higher in mixed infections with other species. The presence of Fusarium avenaceum with other species appeared markedly to promote the production of 5 out of 6 mycotoxins, namely DON, DON-3G, nivalenol, enniatins, and beauvericin. These five mycotoxins profited also from contamination by F. poae. Moreover, the presence of F. graminearum and F. culmorum appeared to be decisive for zearalenone accumulation, which was not correlated with DON levels.

Natural occurrence of emerging Fusarium mycotoxins in feed and fish from aquaculture

A new analytical method for the simultaneous determination of enniatins (ENs) and beauvericin (BEA) in fish feed and fish tissues by liquid chromatography coupled to mass spectrometry with linear ion trap (LC-MS/MS-LIT) was developed. Results showed that the developed method is precise and sensitive. The presence of emerging Fusarium mycotoxins, ENs and BEA, was determined in samples of aquaculture fish and feed for farmed fish, showing that all feed samples analyzed were contaminated with mycotoxins, with 100% coexistence. In aquacultured fish samples, the highest incidence was found in edible muscle and liver. As for the exposure assessment calculated, it was found that average consumer intake was lower than tolerable daily intake (TDI) values for other Fusarium mycotoxins.

Presence of ochratoxin A (OTA) mycotoxin in alcoholic drinks from southern European countries: wine and beer

The main filamentous fungi producers of mycotoxins are Aspergillus spp., Penicillium spp., and Fusarium spp. Their effect can provoke a broad range of toxic properties including carcinogenicity and neurotoxicity, as well as reproductive and developmental toxicities. Ochratoxin A (OTA) is produced by Aspergillus and Penicillium spp. The purpose of this review was to evaluate the risk assessment of OTA in alcoholic drinks (beer and wine) by compiling the results obtained from studies and reviews related to the presence of OTA in these two drinks from southern European countries in the period 2005-2013 and comparing those results with the legislation available in the European Union.

Oxidative stress of alternariol in Caco-2 cells

Alternariol (AOH) is a mycotoxin produced by fungus Alternaria. It is found in a wide variety of fruits and cereals products. AOH is able to damage human health. The aim of this study was to evaluate the cytotoxicity of AOH in human colon adenocarcinoma (Caco-2) cells. Moreover, some events related to oxidative stress were evaluated: reactive oxygen species (ROS) generated by oxidation of 2',7'-dichlorodihydrofluorescein diacetate; peroxidation of lipid (LPO) by malondialdehyde (MDA) production; and antioxidant enzymatic capability of catalase (CAT) and superoxide dismutase (SOD). Cytotoxicity of AOH (from 3.125 to 100 μM) was determined during 24, 48 and 72 h of exposure by different endpoints. AOH decreased cell viability by MTT, NR and PC assays. However, no IC50 values were obtained by any of the assays tested. AOH induced a strong oxidative stress in Caco-2 cells by generation of ROS production and LPO associated with a rise in the SOD activity at all concentration tested. ROS increased 1.2-fold with respect to the control and MDA production ranged from 130% to 250% compared to control. Our results demonstrated that in spite of AOH showing cytotoxic effect on Caco-2 cells at the highest concentration tested, oxidative stress by LPO and ROS was observed at all concentrations assayed. This could cause an injury and be hazardous to health.