Potential of Kale and Lettuce Residues as Natural Adsorbents of the Carcinogen Aflatoxin B in a Dynamic Gastrointestinal Tract-Simulated Model.

Adsorption of the carcinogen aflatoxin B (AFB) onto agro-waste-based materials is a promising alternative over conventional inorganic binders. In the current study, two unmodified adsorbents were eco-friendly prepared from kale and lettuce agro-wastes. A dynamic gastrointestinal tract-simulated model was utilized to evaluate the removal efficiency of the sorptive materials (0.5%, ) when added to an AFB-contaminated diet (100 µg AFB/kg). Different characterization methodologies were employed to understand the interaction mechanisms between the AFB molecule and the biosorbents. Based on adsorption results, the biosorbent prepared from kale was the best; its maximum adsorption capacity was 93.6%, which was significantly higher than that of the lettuce biosorbent (83.7%). Characterization results indicate that different mechanisms may act simultaneously during adsorption. Non-electrostatic (hydrophobic interactions, dipole-dipole interactions, and hydrogen bonding) and electrostatic interactions (ionic attractions) together with the formation of AFB-chlorophyll complexes appear to be the major influencing factors driving AFB biosorption.