Fumonisin elimination and prospects for detoxification by enzymatic transformation

A technology to efficiently reduce the concentration of carcinogenic and toxic fumonisins in food and feed would be desirable. This class of mycotoxins is produced by the maize pathogen Fusarium verticillioides and other fungi. Fumonisins are frequently found in maize from the warm growing regions of the world, sometimes in considerable concentrations. Their molecular similarity with sphingolipids enables their binding to mammalian ceramide synthase, and the resulting interference with sphingolipid metabolism. Recently, we reported on a cluster of genes of Sphingopyxis sp. MTA144 which enables this alphaproteobacterium to degrade fumonisins. These and the previously known fumonisin catabolism genes and enzymes from the black yeast Exophiala spinifera and from bacterium ATCC 55552 allow the consideration of prospects for enzymatic detoxification of fumonisins in food and feed. All the known fumonisin catabolism pathways start by hydrolytic release of the two tricarballylic acid side chains, followed by removal of the 2-amino group from the core chain by different enzymatic mechanisms. The potential for application of feed enzymes for fumonisin detoxification in the gastrointestinal tract of animals is discussed, and possible applications in processing of maize for feed or food are also considered. To be able to evaluate the requirement for, and potential of, a new, enzyme-based fumonisin detoxification technology, an overview of the state of the art of fumonisin elimination and the known chemical reactions of fumonisins in processing or decontamination is also given. There is a special focus on the toxicity of hydrolysed fumonisins, because they can be generated from fumonisins both by an established, traditional method of maize processing, nixtamalisation, and by enzymatic biotransformation. As a complement to other approaches, enzymatic degradation of fumonisins to ameliorate the health risk of contaminated maize for animals, and possibly also for humans, seems feasible.