Identification of cyclodextrin inclusion complex of chlorogenic acid and its antimicrobial activity

Chlorogenic acid is an important bioactive compound which is unstable under ambient conditions. In this work, chlorogenic acid was extracted from tobacco leaf and purified by high performance liquid chromatography. β-Cyclodextrin (β-CD) was used to form inclusion complex with chlorogenic acid. Analyses of differential scanning calorimeter (DSC) and 1H nuclear magnetic resonance (NMR) spectroscopy confirmed the formation of inclusion complex and quinic acid moiety was included within the β-CD cavity. A blue shift of ca. 2 nm for chlorogenic acid was detected after inclusion. The storage stability of chlorogenic acid was apparently improved by measurement of absorbance change during 20 weeks. Through determinations of DPPH radical scavenging and antimicrobial activities, no significant difference was observed between chlorogenic acid and its complex. Therefore, construction of β-CD inclusion complex was helpful for the application of chlorogenic acid.