A Novel Adsorbent Albite Modified with Cetylpyridinium Chloride for Efficient Removal of Zearalenone

Effect of the Structure of Highly Porous Silica Extracted from Sugarcane Bagasse Fly Ash on Aflatoxin B1 Adsorption

Sugarcane bagasse fly ash is industrial waste produced by incinerating biomass to generate power and steam. The fly ash contains SiO₂ and Al₂O₃, which can be used to prepare aluminosilicate. This latter material exhibits high potential as an adsorbent in various applications, including the livestock industry where issues related to contamination of aflatoxins in animal feeds need to be addressed; addition of adsorbents can help decrease the concentration of aflatoxins during feed digestion. In this study, the effect of the structure of silica prepared from sugarcane bagasse fly ash on physicochemical properties and aflatoxin B1 (AFB1) adsorption capability compared with that of bentonite was investigated. BPS-5, Xerogel-5, MCM-41, and SBA-15 mesoporous silica supports were synthesized using sodium silicate hydrate (Na₂SiO₃) from sugarcane bagasse fly ash as a silica source. BPS-5, Xerogel-5, MCM-41, and SBA-15 exhibited amorphous structures, while sodium silicate possessed a crystalline structure. BPS-5 possessed larger pore size, pore volume, and pore size distribution with a bimodal mesoporous structure, while Xerogel-5 exhibited lower pore size and pore size distribution with a unimodal mesoporous structure. BPS-5 with a negatively charged surface exhibited the highest AFB1 adsorption capability compared with other porous silica. However, the AFB1 adsorption capability of bentonite was superior to those of all porous silica. Sufficient pore diameter with high total pore volume as well as high intensity of acid sites and negative charge on the surface of the adsorbent is required to increase AFB1 adsorption in the in vitro gastrointestinal tract of animals.

Efficient and simultaneous removal of aflatoxin B1, B2, G1, G2, and zearalenone from vegetable oil by use of a metal-organic framework absorbent

Vegetable oils are usually cocontaminated with different mycotoxins, including aflatoxins and zearalenone, which cause significant food safety issues. Establishment of multitarget, high-efficiency, and low-cost adsorption methods are considered to be ideal solutions for mycotoxin removal in vegetable oils. In this study, we used metal-organic frameworks (MOFs) were used for the simultaneous removal of aflatoxins and zearalenone from vegetable oils. The results showed that MOF-235 simultaneously removed, within 30 min, more than 96.1% of aflatoxins and 83.3% of zearalenone from oils, and oils treated with MOF-235 exhibited di minimis cytotoxicity. Thus, synthesized MOF-235 exhibited sufficient efficacy to remove the targeted residues, as well as safety and reusability, which could be applied as a novel potential adsorbent in the removal of multiple mycotoxins from contaminated vegetable oils.

Removal of Aflatoxin B1 and Zearalenone in Mixed Aqueous Solution by Palygorskite-Montmorillonite Materials In Situ Prepared from Palygorskite Mineral

In view of the animal feeds inevitably contaminated by multiple mycotoxins, eco-friendly and efficient palygorskite-montmorillonite (Pal-Mt) materials were prepared to remove polar aflatoxin B₁ (AFB₁) and weak polar zearalenone (ZEN) from mixed mycotoxins aqueous solution. The adsorption properties and bonding mechanisms between Pal-Mt materials and mycotoxins (AFB₁ and ZEN) were investigated systematically. The as-prepared Pal-Mt showed excellent adsorption capacity for AFB₁ and ZEN in single- and binary-mycotoxin systems, indicating the effectiveness of Pal-Mt acting as multiple mycotoxin adsorbents. The kinetics of adsorption for ZEN was fast due to the adsorption on the external surface (film and intraparticle diffusion), while AFB₁ molecules permeated into mesopores after the external adsorption for the more planar structure. Adsorption isotherms demonstrated that heterogeneous surface adsorption appeared between Pal-Mt and AFB₁, and monolayer adsorption occurred on Pal-Mt and ZEN for different polarities of mycotoxins. Thermodynamic parameters illustrated that the adsorption process of both AFB₁ and ZEN onto Pal-Mt was spontaneous and endothermic. The adsorption mechanism studies suggested that hydrogen bonding, electrostatic attraction, calcium bridging linkage, and ion-dipole played fundamental roles in the interaction between Pal-Mt and these two mycotoxins.

Theoretical study on charge distribution in cetylpyridinium cationic surfactant

Here, we report the electrostatic potential maxima and partial atomic charges evaluated on cetylpyridinium cation. The Hartree-Fock method and six DFT functionals (namely, PBE, TPSS, B3LYP, PBE0, M06, and wB97) were used to calculate partial atomic charges via CHELPG, Mulliken, Löwdin, Hirshfeld, and natural population schemes. Calculations were performed for the gas phase and for the CPCM water solvated cation, resulting in a set of 70 types of partial atomic charges. The main tendencies in charge deviations were discussed. In comparison with the electrostatic potential-based CHELPG partial charges, Hirshfeld, Mulliken, Löwdin, and NPA partitioning schema lead to an almost steady decrease in the partial charges in the cetyl chain. This agreed closely with the redistribution of electrostatic potential mapped onto the 0.002 e/Bohr³ isodensity surface.