EFFECTIVENESS OF COMPOSITE FEED ADSORBENTS IN BINDING MAJOR MYCOTOXINS UNDER VARIABLE PH CONDITIONS

Abstract

Mycotoxins are toxic secondary metabolites produced by fungi of the genera Aspergillus, Penicillium, Fusarium, Claviceps and Alternaria and represent a significant threat to the safety of cereal crops and animal feed. These compounds may accumulate at various stages of production, storage, and transportation, which necessitates the development and application of effective strategies to reduce their toxic effects. The aim of the study was to perform a comparative evaluation of the adsorption capacity of three mycotoxin-binding agents. The study was conducted under in vitro conditions; therefore, the adsorption efficiency observed may differ under in vivo gastrointestinal conditions. Three commercial mycotoxin binders were tested, each containing 70% inorganic sorbent from the silicate group (bentonite, zeolite, or diatomite) and 30% organic component based on yeast cell walls (sources of mannan oligosaccharides and β-glucans). In preparation No. 1, the organic fraction consisted of yeast cell walls containing 33% MOS and 25% β-glucans; preparation No. 2 contained 20% MOS and 35% β-glucans; and No. 3 contained 20% MOS and 20% β-glucans. The adsorption capacity of the mycotoxin-binding preparations was determined under laboratory conditions using the adsorption isotherm method. All experiments were conducted in eight replicates. The results showed that the highest adsorption efficiency of deoxynivalenol (DON), aflatoxin B1, and zearalenone (ZEA) was observed under acidic conditions (pH 3). The highest sorption of DON, ZEA, and fumonisin B1 (FB1) was achieved by sorbent No. 1 (containing 33% MOS and 25% β-glucans), especially at pH 3. In addition, sorbent No. 1 demonstrated 100% binding of aflatoxin B1 across the entire pH range studied (pH 3, 5, and 7), indicating the stability of its adsorption properties. In contrast, sorbents No. 2 and 3 exhibited relatively low and unstable activity against fumonisin B1; at pH 7, the values ranged from 0.4% to 2.8%  The results obtained indicate that sorbent No. 1 can be considered the most versatile and effective for binding the major mycotoxins evaluated in this study.