Abstract:
This study employed diverse deep eutectic solvents (DESs) to pretreat corn starch, followed by enzymatic hydrolysis for porous starch synthesis and subsequent curcumin encapsulation. The structural characteristics of porous starch matrices, both pre- and post-encapsulation, were characterized using scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and laser diffraction particle size analysis. Encapsulation efficiency (EE), loading capacity (LC), and release properties in simulated gastric and intestinal fluids were systematically evaluated. Results indicated that the DES-pretreated porous starch matrices exhibited significant increases in both pore density and dimensions compared with the control group (
P<0.05). Post-encapsulation analysis confirmed retention of the A-type crystalline pattern despite significantly reduced relative crystallinity, accompanied by particle size enlargement and disappearance/shifts of characteristic curcumin FTIR peaks. The ChCl-G pretreated group achieved optimal EE of 66.02% and LC of 3.79 mg/g, significantly surpassing other comparative groups. Similarly, ChCl-LA and ChCl-AA pretreated matrices exhibited superior performance versus pH-equivalent organic acid solutions (
P<0.05). Furthermore, DES-pretreated samples demonstrated sustained release capabilities in simulated gastrointestinal fluids. In conclusion, DES pretreatment effectively modulates structural properties of porous starch, thereby enhancing both encapsulation performance and
in vitro sustained release characteristics for curcumin.