Adsorptive removal of cholesterol by biodegradable zein-graft-β-cyclodextrin film

A novel bio-based zein- graft -β-cyclodextrin film was synthesized for cholesterol adsorption at room temperature. Immobilization of β-cyclodextrin (β-CD) to zein was achieved by the Maillard reaction and the zein- graft -β-CD powders showed higher glass transition temperature and higher solubility in water. Zein- graft -β-CD films, prepared by solvent evaporation casting, showed excellent capacity for cholesterol adsorption. The F 1:1 has the best adsorption properties, and the maximum adsorption capacity can reach 5.70 ± 0.56 mg cholesterol/g film. The adsorption cholesterol mechanism of zein- graft -β-CD film was correspond to the pseudo-first order kinetic model. In addition, the zein- graft -β-CD film retained an adsorption capacity of 3.10 ± 0.89 mg cholesterol/g film after three reuses. Using composite enzyme (1 mg/mL papain and 1 mg/mL amylase), the film (F 1:1 ) degradation reached 98.81% in 1 week. These results suggest that zein- graft -β-CD film has potential as a nature-based adsorbent for cholesterol adsorption and could be used in the food industry.