Development of cannabidiol full-spectrum oil/2,6-di-O-methyl-β-cyclodextrin inclusion complex with enhanced water solubility, bioactivity, and thermal stability

Abstract

Industrial hemp is an important economic crop. The ethanol extract of its leaf is also known as cannabidiol full-spectrum oil (CFSO) and has a lot of health benefits. But its applications in many fields are limited owing to the poor thermal stability and low aqueous solubility. In this study, 2, 6-di-O-methyl-β-cyclodextrin (DM-β-CD) was used to prepare inclusion complex (IC) of CFSO to enhance its thermal stability and water solubility. Phase solubility study indicated that CFSO formed ICs with DM-β-CD at a 1:1 stoichiometric ratio. The complexation rate of CFSO/DM-β-CD IC was 91.5%. The results of SEM, FT-IR, DSC, PXRD, NMR, and molecular docking revealed that the bioactive components of CFSO were embedded into DM-β-CD cavities. After complexation, the aqueous solubility of CFSO in CFSO/DM-β-CD IC was increased from 0.046 to 12.4 μg/mL. The DPPH and ABTS EC50 values of CFSO/DM-β-CD IC were 130.5 and 12.0 μg/mL respectively, which indicated that the antioxidant ability of CFSO/DM-β-CD IC was stronger than that of CFSO. The MICs of CFSO/DM-β-CD IC were around 6.25–12.5 μg/mL for Escherichia coli and 12.5–25 μg/mL for Bacillus subtilis. The data showed that the antibacterial activity of CFSO was nearly not influenced by complexation. The thermal stability of CFSO was also improved after inclusion. The findings could promote the use of CFSO and the development of the industrial hemp industry.