Mycotoxins: An Underhand Food Problem.

Among the food safety issues, the occurrence of fungal species able to produce toxic metabolites on the agro-food products has acquired a general attention. These compounds, the mycotoxins, generally provided of low molecular weight, are the result of the secondary metabolism of the toxigenic fungi. They may have toxic activity toward the plants, but mostly represent a serious risk for human and animal health worldwide, since they can be accumulated on many final crop products and they have a broad range of toxic biological activities. In particular, mainly cereals are the most sensitive crops to the colonization of toxigenic fungal species which accumulate in the grains the related mycotoxins both in the field, until the harvest stage, and in the storage. According to a Food and Agriculture Organization study, approximately 25 % of the global food and feed output is contaminated by mycotoxins. Therefore, since a large proportion of the world's population consumes, as a staple food, the cereals, the consumption of mycotoxin-contaminated cereals is a main issue for health risk worldwide. Furthermore, mycotoxin contamination can have a huge economic and social impact, especially when mycotoxin occurrence on the food commodities is over the regulation limits established by different national and transnational institutions, implying that contaminated products must be discarded. Finally, the climate change due to the global warming can alter stages and rates of toxigenic fungi development and modify host-resistance and host-pathogen interactions, influencing deeply also the conditions for mycotoxin production that vary for each individual pathogen. New combinations of mycotoxins/host plants/geographical areas are arising to the attention of the scientific community and require new diagnostic tools and deeper knowledge of both biology and genetics of toxigenic fungi. Moreover, to spread awareness and knowledge at international level on both the hazard that mycotoxins represent for consumers and costs for stakeholders is of key importance for developing all possible measures aimed to control such dangerous contaminants worldwide.

Occurrence of toxigenic fungi and determination of mycotoxins by HPLC-FLD in functional foods and spices in China markets.

Twenty-four samples including 14 functional foods and 10 spices obtained from Chinese markets were examined for their mould profile. The mycotoxin contamination levels were also determined by an optimized HPLC-FLD method. 124 fungal isolates belonging to four different genera were recovered with Aspergillus and Penicillium as predominant fungi, with an incidence of 66.1% and 15.3%, respectively. In functional foods Aspergillus niger section (57.1%) was isolated more frequently, followed by Aspergillus flavi section (50.0%) and Aspergillus ochraceus section (21.4%), with the most contaminated samples being Coix seeds. Similar fungal presence and frequency were encountered in spice with A. niger section group (60.0%) and A. flavi section (40.0%) as main fungi. Cumin and Pricklyash peel samples showed the highest fungal contamination. Four functional foods and three spices were found to be positive at low levels for mycotoxins including aflatoxin B1 (up to 0.26µg/kg) and ochratoxin A (OTA) (5.0µg/kg). The more frequently detected mycotoxin was AFB1 (16.7%).