Team:TU Darmstadt/problem

From 2013.igem.org








The problem of mycotoxins

Mycotoxins produced by mould fungus are present in our daily life and are harmful for humans as
well as for animals.

peffer

White tea incubated for 3 days at 30 °C on sabouraud agar.

Grain, coffee, nuts and pulses are some of the foods commonly contaminated. It is estimated that about a quarter of the world’s food crops is affected [1].
The Food and Agriculture Organisation of the United Nations (FAO) and the World Health Organisation (WHO) have developed three benchmarks of risk analysis: risk assessment, risk management and risk communication. Risk assessment involves hazard identification (i.e. type of mycotoxin), hazard characterization (including toxicity and dose-response), exposure assessment (including occurrence in food, levels and amount of food consumed) and risk characterization to assess food safety risks.

pilz

Colonies of mold fungi.

Using this information, risk management strategies can be put in place and their performance may be evaluated [2].






aflab1

Chemical structure of aflatoxin B1.



Aflatoxins are one of the most dangerous known mycotoxins with about 20 different types of toxins existing. The most important types of aflatoxin are B1, B2, G1 and G2. The most dangerous is aflatoxin B1, it posseses a high toxicity and is the strongest known carcinogenic natural material. Commonly contaminated foods are corn, rice, sorghum, nuts and a huge amount of spicery. In the year 2008 the german „Bundesamt für Verbraucherschutz und Lebensmittelsicherheit“ tested 88 different samples of rice and in 6.8% of the samples aflatoxin B1 was found. The highest acceptable amount in europe is 2.0μg/kg and in 1.1% of those rice samples a higher amount of aflatoxin B1 was determined.
The three benchmarks are all covered by the detection system we have developed.


fumo

Chemical structure of fumonisin B1.


Fumonisin B1 is mainly produced by Fusarium verticillioides and other Fusarium species, which occur in corn and wheat. While its acute toxicity is relatively low it is associated with esophageal cancer and neuronal damage in the human embryo. Fumonisin B1 inhibits sphingolipid metabolism and ceramide synthesis. While there’s not enough data on kinetics and metabolism of fumonisin B1 in humans, the World Health Organization determined the tolerable daily intake (TDI) to be at 2 µg/kg body weight. Especially in regions where corn makes up the greatest part of the daily diet, these levels are often exceeded.





For further information on the today standard of dealing with the thread of mycotoxines visit: