Development of Anacardic Acid/hydroxypropyl-β-cyclodextrin inclusion complex with enhanced solubility and antimicrobial activity

Anacardic Acid (AnAc), a key constituent of cashew nut shell liquid (CNSL), has been reported to exhibit antibacterial activity against S. aureus but its bioactivity and clinical applicability are limited owing to its poor water solubility and physicochemical stability. The aim of the present study was to develop inclusion complex of AnAc (C-15:3) and hydroxypropyl-beta-cyclodextrin (HP-beta-CD) to improve its aqueous solubility and antimicrobial activity. The inclusion complex was prepared using the co-evaporation method considering different molar ratios of AnAc (C-15:3) and HP-beta-CD. The prepared inclusion complex was characterized using FT-IR, DSC, XRD, SEM, and H-1 NMR, which provided appropriate evidence to confirm the formation of the inclusion complex. The prepared inclusion complex demonstrated similar to 2009 times improved aqueous solubility. The developed complex maintained the antimicrobial activity of pure AnAc against S. aureus. AnAc/HP-beta-CD complex exhibited excellent biofilm dispersal potential against mature biofilms. Confocal laser scanning microscopy (CLSM) demonstrated a remarkable decrease in bacterial biomass and thickness upon treatment with the inclusion complex. Conclusively, the developed inclusion complex of Anacardic Acid (C-15:3) can be effectively used to overcome the poor aqueous solubility and improve the therapeutic efficacy for many other indications. (C) 2019 Elsevier B.V. All rights reserved.