Neutralization of zearalenone by an adsorption feed additive based on bentonite clay modified with the bacterial culture Bacillus subtillis

Mycotoxins are harmful substances produced by mold fungi that may be present in livestock feed and food products. Bentonite clay, as well as feed additives based on bentonite clay, have proven their effectiveness and are known as adsorbents of toxins of various natures. Currently, a promising direction is the development of adsorption additives that include probiotics. Bacteria of the genus Bacillus have antifungal and antagonistic effects on phytopathogenic fungi.

Under sterile conditions, upon reaching the logarithmic growth phase of Bacillus subtillis KE1 VKM B-3705D microorganisms, sodium bentonite clay was added in a carrier:biomass ratio of 1:5, then lyophilized and stored at room temperature. The study was carried out by HPLC on an ACQUITY WATERS chromatograph with a BEH C18 reversed-phase column: eluent - gradient mixture (acetonitrile, water, methanol), 230-400 nm, 20 minutes, column temperature – 40 °C; mobile phase flow rate 0.3 ml/min. The analyzed raw material was feed contaminated with an indigenous strain of the mold fungus Fusarium sp., the metabolite of which, is zearalenone. Zearalenone neutralization was assessed using the following scheme: on the 10th day after infection, 10.0±0.1 g of contaminated feed were weighed into conical flasks, 10 ml of 1 M Tris-HCl (pH 7.5), 100 ml of distilled water and a weighed portion of the adsorption additive (0.10; 0.25; 0.50; 0.75; 1.00 g) were added. The flasks were placed in a shaker-incubator for 24 hours at a T=40 °C, then zearalenone was extracted and subjected to HPLC. A similar experiment was conducted with the sodium form of bentonite clay, produced by KalachBent LLC without a bacterial component.

It was found that an adsorption feed additive obtained from the sodium form of clay in combination with B.subtillis KE1 VKM B-3705D bacteria neutralizes the mycotoxin zearalenone in contaminated feed more effectively than the sodium form without the bacterial component.