Aquaculture for all

Fumonisins in Fish

Nutrition Post-harvest

Fumonisins are a group of recently discovered mycotoxins which belong to the family of Fusarium toxins. The contamination of feedstuffs with mycotoxins poses a serious threat to the health and productivity of animals and cause great economic losses.

Fumonisins are mainly produced by Fusarium verticillioides (syn. moniliforme) as well as by Fusarium proliferatum and they occur predominately in maize and maize-based feeds (Ross et al. 1992).

In 1988 they were first identified and isolated and so far there are 28 fumonisin analogues known (Gelderblom et al. 1988; Rheeder et al. 2002). Fumonisins are divided into four groups: Serial A, B, C and G. With regard to their toxicity the B-type fumonisins represent the most important ones (Marasas 1996). In naturally contaminated food and feed fumonisin B1 represents about 70% - 80% of the total fumonisin content (Krska et al. 2007).

Fumonisins are very polar and water soluble compounds. Unlike other mycotoxins, they have a long chain structure. Chemically, they are polyhydroxyl alkylamines esterified with two carbon acids, i.e. tricarballylic acid (TCA). The four common members of the type B fumonisins differ by presence and position of the free hydroxyl groups respectively (ApSimon 2001). The one-sided or bilateral elimination of TCA results in partial hydrolyzed fumonisin or hydrolyzed fumonisin (HFB1). Fungal colonization and growth and/or mycotoxin production are influenced by a variety of factors. Optimum conditions for fumonisin production are temperatures between 10°C and 30°C with a water activity (amount of free available water) of 0.93 aw (Marin et al. 1999).

A published survey about the occurrence of mycotoxins in Asia initiated by Biomin GmbH together with Romer® laboratories in Singapore reported that 58% out of 960 feed raw material samples were contaminated with fumonisins. In this report the highest level of fumonisins detected was 21.5 mg/kg in a corn sample from China (Rodrigues and Wegleitner 2008). In Europe, levels up to 250 mg/kg were reported in maize from Italy (Bottalico et al. 1995) . Table 1 gives examples on high concentrations of fumonisins found in maize samples around the world.

Table 1: Examples on high concentrations of fumonisins in maize samples

Fumonisin [mg/kg] Country References
250 Italy Bottalico et al. 1995
160 Korea Seo and Lee 1999
155 China Chu and Li 1994
122 USA Wilson et al. 1990
117 South Africa Rheeder and Marasas 1998
75 Hungrey Fazekas et al. 1998
21.5 China Rodrigues and Wegleitner, 2008
14.7 China Tan, 2007
10.6 China Chin and Tan, 2006

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