Toxicity of fumonisin B1 (FB1), the most common fumonisin mycotoxin, can be significantly decreased by enzymatic cleavage of its two tricarballylic acid groups, using fumonisin esterase. An enzyme product should be formulated in a solid form for use as a feed supplement, and have a long shelf-life and high heat stability. Therefore, a fumonisin esterase (further referred to as FE2) was expressed in Pichia pastoris and the enzyme was immobilized with different techniques. Covalent immobilization of FE2 on aminefunctionalized zeolite, crosslinked with glutaraldehyde, resulted in low specific capacity (0.8 mg enzyme/g zeolite), and poor stability. Reversible immobilization of FE2 on different solid carriers resulted in even > 95% immobilization efficiency, and the enzyme could be recovered after resuspension in buffer, without significant loss of activity. This immobilization method resulted in at least 3 years of shelf-life even at 50 °C. The thermal stability of these products significantly increased compared to the enzyme solution; the products retained even nearly 100% of their activity after incubating at 100 °C for 30 minutes. This increased heat stability makes the product compatible with feed processing techniques, such as pelleting.

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