Comprehensive Conformational Study of Key Interactions Involved in Zearalenone Complexation with β-d-Glucans

Abstract

The beta-D-glucans from the cell wall of Saccharomyces cerevisiae have shown in vitro affinity for zearalenone. For this reason, their utilization as dietary adsorbent, to reduce the bioavailability of zearalenone, is of practical interest. Our study used powerful devices to elucidate the spatial conformation and molecular sites of interaction between ZEN and beta-D-glucans. In this respect, 1H NMR spectroscopy implicated the hydroxyl groups of the phenol moiety of zearalenone in the complexation by laminarin, a pure beta-(1,3)-D-glucan. X-ray diffraction determined that laminarin displays the conformation of a single-helix with six beta-D-glucopyranose residues per turn. At this stage, molecular modeling was useful to locate the interaction sites and to propose highly probable complexes of zearalenone with laminarin fragment. Interestingly, the beta-(1,3)-D-glucan chain favors a very stable intra-helical association with zearalenone, nicely stabilized by beta-(1,6)-D-glucans side chains. Both hydrogen bonds and van der Waals interactions were precisely identified in the complex and could thus be proposed as driving interactions to monitor the association between the two molecules.

Vacuum-ultraviolet circular dichroism study of oligosaccharides using a synchrotron-radiation spectrophotometer

“…Further, X-ray diffraction and NMR methods suggested that laminarin is composed of three strands of the parallel right-handed helix, with six glucose residues per turn [33,44]. As shown in Fig.…”

Yeast cell based feed additives: studies on aflatoxin B1and zearalenone

“…The mechanism of binding by β-Dglucans has been investigated by Yiannikouris and co-workers and has been discussed in several publications, e.g. (Yiannikouris et al 2004a;Yiannikouris et al 2006;Yiannikouris et al 2004b;Yiannikouris et al 2004c). It was shown that it is important to differentiate between the adsorption affinity of whole yeast cell wall and processed cell wall.…”

Myco-toxins Monitoring Device and their Management Strategies through Detoxifying Agents in Feed

“…Some AAs, have shown also other health benefits than those of counteracting the direct and indirect effects due to mycotoxins. The cell wall of Saccharomyces cerevisiae is composed of beta-D-glucans which have, besides their high binding properties towards ZEA and AFB1 and to a lesser extent to FB1 and DON, a well-known ability to stimulate the immune system (Yiannikouris et al, 2004). Regarding the ability of kaolin when given to animals in their diet, to bind, in addition to aflatoxins, heavy metals, plant metabolites, poisons, diarrhea-causing enterotoxins, and pathogenic microorganisms.…”