Starch is an abundant, renewable, and low cost material that has been extensively studied for its role in crystallization. Herein, we developed a facile and green approach to produce the starch-based microparticles (SMPs) that could encapsulate curcumin during the self-association of short glucan chain obtained from waxy maize starch. Scanning electron microscopy (SEM) analysis indicated that the diameters of curcumin-loaded SMPs were ranged from 1.5 μm to 3 μm. The characteristics of the curcumin-loaded SMPs were evaluated via Raman spectroscopy, confocal microscopy, UV spectrophotometer, and X-ray diffraction (XRD). The results showed that the suspended curcumin was encapsulated in SMPs in amorphous form with a encapsulating efficiency of about 96.36%. Photostability test confirmed that curcumin that is loaded inside SMPs was effectively protected against the photodegradation. Curcumin-loaded SMPs can be used not only in food industry for extending the shelf life of curcumin, but also in pharmaceutical industry to design effective carrier for oral delivery.
Starch is an abundant, renewable, and low cost material that has been extensively studied for its role in crystallization. The aim of this study is to develop a convenient and green approach to synthesize starch nanoparticles (StNPs). Short glucan chains were successfully prepared by using pullulanase that could debranch the amylopectin obtained from waxy maize starch. StNPs were prepared via the self-association of short glucan chains, of which the crystallinity structure changed from A-type (native starch) to B-type (starch nanoparticles) through the enzymatic hydrolysis and reassembly process at 4°C. Scanning electron microscopy (SEM), X-ray diffraction (XRD), dynamic light scattering (DLS) and differential scanning calorimetry (DSC) were used to characterize the morphology and crystalline structure of StNPs. The results showed that the diameter of StNPs ranged from 300 nm to 1.5 μm, depending on the initial concentration of short glucan chains and self-assembly time. The developed approach could produce well-defined and uniform starch nanoparticles that could readily be employed to encapsulate various functional guest molecules in biocompatible starch based nanoparticles in food industry.