Physical and antifungal properties of β-cyclodextrin microcapsules and nanofibre films containing cinnamon and oregano essential oils

Abstract

The aim of this study was to investigate the physical and antimicrobial properties of fabricated nanofibre for active packaging systems. Active microcapsules and nanofibres derived from precipitating β-cyclodextrin (β-CD) with cinnamon (CIN) and oregano (OREG) essential oils (EOs) were developed and their in vitro antifungal activity against Botrytis sp., an important fruit pathogen was determined. Solutions of β-CD and CIN- or OREG-EOs were subjected to co-precipitation to induce micro-encapsulation. Thereafter, the properties of the complexed microcapsules were assessed. Solid-state nuclear magnetic resonance (NMR) showed the presence of new carbon peaks in the β-CD complex spectra, which were absent in the plain β-CD spectrum confirming encapsulation of EOs. Encapsulation of EOs was also confirmed by thermogravimetric analysis (TGA), which indicated that the thermal degradation of β-CD-EO complex occurred over a lower temperature (270 °C) compared to plain β-CD (300 °C). Gas chromatography-mass spectrometry (GC-MS) showed that the amount of volatile EOs released was lower for OREG-EO compared to CIN-EO. Electrospun active nanofibres (∼100–300 nm) were successfully fabricated from chitosan/polyvinyl alcohol/β-cyclodextrin (CH/PVA/β-CD) solution with EOs. The nanofibres ability to release EO volatiles and antifungal activity were confirmed.