Total phenolic content and antioxidant activity of spray-dried microcapsules propolis from Tetragonula species

Abstract

The objective of this study was to determine the total phenolic content (TPC) and antioxidant activity (AA) of propolis microcapsules from Tetragonula spp. A microplate reader was used to determine TPC and AA. Smooth propolis extract with the highest TPC and AA was used as core material for microencapsulation with maltodextrin and gum arabic as coating materials, prepared by using the spray-drying method. Scanning electron microscopy was used to analyze the morphologies of microcapsules. The spray-dried propolis (SDP) microcapsules exhibited the high TPC of 237.33 mg GAE/g, AA with the EC50 value of 34.823 µg/ml, moisture content at 6.32%, the water solubility was 92.48%. The SEM images of SDP microcapsules showed uniform spherical particles with sizes ranging from 0.8 to 4 µm. The conclusion was propolis with high total phenolic content can be prepared as a core material for microencapsulation with maltodextrin and gum arabic as a coating material using the spray-drying method. The microencapsulation could protect total phenolic compounds and antioxidant activity of propolis. It also improved their physical appearance and solubility index.