In vitro and in vivo studies to assess the effectiveness of cholestyramineas a binding agent for fumonisins

Several adsorbent materials were tested at 1 mg/ml for their in vitrocapaci ty to adsorb fumonisin B-1 (FB1) from aqueous solutions. Cholestyramine sho wed the best adsorption capacity (85% from a solution containing 200 mug/ml FB1) followed by activated carbon (62% FB1). Bentonite adsorbed only 12% o f the toxin from a solution containing 13 mug/ml FB1, while celite was not effective even at the lowest tested FB1 concentration (3.2 mug/ml). Cholest yramine was tested in vivoto evaluate its capacity to reduce the bioavailab ility of fumonisins (FBs) in rats fed diet contaminated with toxigenic Fusa rium verticillioidesculture material. Rats were exposed for one week to FBs -free diet, FBs-contaminated diet containing 6 or 20 mug/g FB1 + FB2 and th e same FBs-contaminated diet added of 20 mg/g cholestyramine. The increase of sphinganine/sphingosine (SA/SO) ratio in urine and kidney of treated rat s was used as specific and sensitive biomarker of fumonisin exposure. The a ddition of cholestyramine to the FBs-contaminated diets consistently reduce d the effect of FBs by reducing significantly (P < 0.05) both urinary and r enal SA/SO ratios.