Obtaining and characterization of bentonite organophilic incorporated with geranyl acetate and its application as mycotoxins? binder in simulated gastrointestinal fluids

One of the major problems linked to the animal feed industry is the presence of mycotoxins, substances produced by fungi, which even in low concentrations can cause health-related inconveniences and severe economic losses. This study reports the production of organophilic bentonite incorporated geranyl acetate (GA) 0.4 (w/w) (BentODA). The synthesized composite was employed to remove carcinogenic mycotoxins Aflatoxin B1 (AFB1). The product was characterized by FRX, XRD, FTIR, TGA, and BET/BJH techniques, while quantifying mycotoxins was performed using HPLC/LC-MS. The effect of intestinal fluids (pH 6.5, the average pH of the intestine, or pH 3.5, the average pH of the stomach) on the adsorption performance of Bent-ODA-GA was systematically investigated. This new material was preliminary evaluated for its antifungal activity against Aspergillus havus and Aspergillus niger. XRD showed that GA was intercalated in bentonite modified by ODA, and FTIR confirmed the presence of GA in the Bent-ODA structure. Furthermore, the product showed the presence of mesopores, and reduced pore volume compared to Bent-ODA. Preliminary results showed that Bent-ODA-GA reduced fungal growth, which allows only traces of fungal growth on its surface, filling <10% of plate, receiving a rating 1 according to ASTM G21-15. The adsorption kinetics showed that to Bent-ODA, 45 min is enough time of contact with AFB1 to reduce it to acceptable levels by legislation, this being 20 mu g center dot kg-1, regardless of the pH used, while for Bent-ODA-GA the time necessary to reach levels that are according to the legislation it is 120 min for a pH of 3.5 and 100 min for a pH of 6.5. Therefore, attributed to the advantages of being efficient, Bent-ODA-GA could be envisaged as a promising adsorbent for the enhanced sequestration of Aflatoxin B1.