Preparation and characterization of inclusion complex of benzyl isothiocyanate extracted from papaya seed with β-cyclodextrin.

The inclusion complex of benzyl isothiocyanate (BITC), extracted from papaya seed with β-cyclodextrin (β-CD), was prepared. Different analytical techniques, such as Fourier transform infrared spectroscopy, thermal analysis, X-ray diffractometry, particle size distribution analysis and (1)H Nuclear magnetic resonance analysis, were used to investigate the characterization of the inclusion complex (BITC-β-CD). All these approaches indicated that the inclusion complex was capable of being formed. The inclusion complex exhibited different spectroscopic and thermodynamic features and properties from BITC, and we deduced the possible inclusion modes for BITC-β-CD. The calculated apparent stability constant of the BITC-β-CD was 600.8l/mol, and the aqueous solubility of BITC was indistinctively improved by phase solubility studies. The results illustrated that β-CD was a proper excipient for increasing the stability and controlled release of BITC. Thus, β-CD complexation technology would be a promising approach, in expanding the application of BITC as a food antibacterial agent.