Application of Prunus armeniaca gum exudates and chitosan for encapsulation of Pomegranate peel extract as a natural antioxidant

The aim of the present work was to optimize the encapsulation of Pomegranate peel extract (PPE) using Prunus armeniaca gum exudates (PAGE) and chitosan (CS) as wall materials, and to investigate the effect of pH on surface charge, particle size, polydispersity index and the extract retention of the microparticles (MPs). Furthermore, antioxidant and antimicrobial activities of both pure and encapsulated PPE were examined. Based on the values of Hausner ratio (1.17) and Carr’s index (14.9%), PAGE/CS MPs powder had excellent flow property. The antiradical activity of pure extract and PPE-loaded particles revealed that PPE-loaded PAGE/CS MPs possessed higher radical scavenging activity than pure extract. A clear antibacterial activity was observed for PPE-loaded PAGE/CS MPs. In vitro release test indicated a sustained release of PPE (only 14.2% of phenolic compounds were released from PAGE/CS MPs to simulated stomach medium). The Korsmeyer-Peppas model could successfully describe the release behavior of PPE from PAGE–CS MPs (R2 = 99). Overall, PAGE/CS MPs can be regarded as suitable micromaterials for the protection and controlled delivery of natural antioxidants/antimicrobial agents, such as PPE.