Characterization of β-cyclodextrin Self-Aggregates for Eugenol Encapsulation

Abstract

The application of β-cyclodextrin(CD)-assisted molecular encapsulation of neutraceutical ingredients, functional food in food products, hydrophobic drugs, and volatile substances helps protect the active ingredients against oxidation, loss of volatile compounds and light-induced decomposition and increases the solubility of hydrophobic medicines. Self-assembly aggregation of CDs has been extensively investigated from the aggregation of native CDs to high-order complex aggregates. The increasing complex order of the aggregates is dependent on some parameters such as pH, temperature, time and concentration. The aim of this study was to investigate the effects of the aggregation behaviour of β-cyclodextrin (CD)-eugenol complexes induced at shaking times on the release characteristic at various relative humidity and storage temperatures. The particle size started to increase after shaking for 8 h at 650 nm, and then, significant aggregation (1,110 nm) was observed after 24 h. The retention rate of eugenol significantly increased according to storage duration under various relative humidity and temperature conditions. Prolonged shaking time enhanced the self-aggregation of β-CD-eugenol complexes resulting in eugenol release behavior due to their effect on the aggregation mechanism, as assessed by TEM observation. The aggregation of β-CD-eugenol complexes could be attributed to the slow release of eugenol owing to the presence of a thick layer of β-CD aggregates.