Release characteristics and antibacterial activity of solid state eugenol/β-cyclodextrin inclusion complex

A solid state eugenol/β-cyclodextrin inclusion complex (EG/β-CD) was prepared by lyophilization method and characterized by Powder X-ray Diffraction (XRD) and Fourier Fransform Infrared Spectroscopy (FTIR). UV–Vis spectrometer was used to determine the EG content encapsulated in the complex. In order to estimate the release characteristics of the EG/β-CD powder, Avrami’s equation and Thermogravimetric (TG) analyzer were, respectively, used. The loss percentage of EG was no more than 10 wt% for 4 week exposing at 25 °C and 75% humidity, and the release of EG is controlled by a combination mechanism of diffusion and first-order mode. TG results not only proved the thermo stability of the EG in EG/β-CD complex, but also clarified the thermal decomposition behaviors of the EG/β-CD. The antibacterial activity of the EG/β-CD complex was investigated using agar cup-plate diffusion method and bacterial strains of Escherichia coli , Salmonella paratyphi B, and Staphyloccocus aureus were used. The results indicated that EG/β-CD had a selective antimicrobial active against Escherichia coli .