Release Profiles of Natural Antioxidant Microcapsules from Hard Gelatin Capsules

Abstract

Microencapsulation is a process of coating droplets or particles with specific materials to provide lightweight capsules used in food ingredients, bioactive compounds, enzymes, live cells, or other materials at a micrometric level. Moreover, this technology in product development of the food, beverage, and health sectors provides innovative products with better stability, functionality, and prolonged releases. This study aims to microencapsulate a natural antioxidant of Cantigi, formulate it into gelatin hard capsules, and evaluate the release profiles. The Cantigi extract was microencapsulated using ethyl cellulose polymer into three microcapsule formulations (MC1, MC2, and MC3), made by solvent evaporation. The characterization of ethyl cellulose microcapsules included color, odor, particle size, shape, recovery, moisture content, encapsulation efficiency, drug loading, density, and antioxidant activities. Then, three hard-gelatin capsules, HGC1, HGC2, and HGC3, were formulated containing the microcapsule with the most potent antioxidant activity, microcrystalline cellulose, and colloidal silicon dioxide. The results showed that the MC1 was the most potent microcapsules, while the HGC3 was the highly potent hard-gelatin capsule dosage form. The HGC3 showed the slowest release compared with HGC1 and HGC2. By analyzing the kinetics of HGC3 using zero-order, first-order, Higuchi, and Kosmeyer-Peppas models, the release profile of HGC3 showed best fit with the first-order model kinetics, consistent with a previous study. Moreover, all hard gelatin capsule dosage forms show a biphasic slow-release profile within 60 minutes. The conclusion is that this study can formulate microcapsules and hard gelatin capsules with antioxidant-potent activities (IC50 < 50 ppm). Then, the Cantigi releases from the hard-gelatin capsule formulation follow the first-order and biphasic slow-release profiles.