Fumonisins

Fumonisins are a group of chemically very similar mycotoxins that are produced by different Fusarium species. They were first isolated from a culture of Fusarium verticillioides in 1988 .

Fumonisins are produced by Fusarium verticillioides and F. proliferatum in particular on maize , but also on other types of grain . The ubiquitous distribution of these mushrooms ensures an equally ubiquitous distribution of their poisons.

properties

Fumonisins are relatively resistant to chemicals. Processing and storage of contaminated food usually does not lead to a decrease in the concentration of fumonisins. Only the good water solubility of these mycotoxins can lead to leaching in corresponding processes. The fumonisin ester bonds are hydrolyzed under basic conditions , but the alcohols formed are also toxic. Their structure is similar to that of sphingosine . The biosynthesis takes place via a polyketide path.

Since 1988 28 different fumonisins have been discovered. They are classified as A-, B-, C-, D-, P-fumonisins. The most common are those of group B, of which fumonisin B _{1 is} the most widespread.

Structure of the fumonisins B ₁ to B ₄

Fumonisin	General structure	R 1	R 2	CAS no.
B 1		-OH	-OH	116355-83-0
B 2		-H	-OH	116355-84-1
B 3		-OH	-H	136379-59-4
B 4		-H	-H	136379-60-7

Biological importance

Fumonisins prevent ceramide synthesis by preventing the transfer of acyl groups to sphingosine . They are inhibitors of sphingosine- N -acyltransferase ( EC  2.3.1.24 ).

Since ceramides are an important component of many biomembranes , the damage pattern is correspondingly wide-ranging.

Fumonisins are suspected of being carcinogenic in humans . An increased incidence of esophageal carcinomas was found with increased consumption of fumonisins (e.g. with a diet dominated by corn) . An increased rate of embryonic malformations (e.g. spina bifida ) is also discussed in connection with a diet rich in corn and the corresponding exposure to fumonisin .

safety instructions

A TDI of 2 µg / kg was given by the Scientific Committee on Food of the European Commission as well as by the Expert Panel of the Food and Agriculture Organization (FAO) and the World Health Organization (WHO), the Joint FAO / WHO Expert Committee on Food Additives (JECFA) . Legal maximum levels (sum of fumonisin B ₁ and B ₂ ) for corn flakes are 100 µg / kg and for other corn products 500 µg / kg.

See also

• Zearalenone
• Deoxynivalenol
• Fusariosis

Web links

• European Commission:
  • Opinion of the Scientific Committee on Food on Fusarium-toxins Part 3: Fumonisin B ₁ (FB ₁ ) (PDF; 185 kB)
  • Updated opinion of the Scientific Committee on Food on Fumonisin B ₁ , B ₂ and B ₃ (PDF; 180 kB)

Individual evidence

1. ^ WC Gelderblom, K. Jaskiewicz, WF Marasas, PG Thiel, RM Horak, R. Vleggaar, NP Kriek: Fumonisins - novel mycotoxins with cancer-promoting activity produced by Fusarium moniliforme. In: Applied and environmental microbiology . Volume 54, Number 7, July 1988, pp. 1806-1811, PMID 2901247 , PMC 202749 (free full text).
2. ↑ Amendment of the Mycotoxin Maximum Amount Regulation (MHmV), Federal Law Gazette 2004 Part I No. 5, p. 151.