Abstract
Context: Caffeic acid is described as antibacterial, but this bioactive molecule has some issues regarding solubility and stability to environmental stress. Thus, encapsulation devices are required. Objective: The aim of this work was to study the effect of the caffeic acid encapsulation by cyclodextrins on its antibacterial activity. Materials and methods: The interactions between the caffeic acid and three cyclodextrins (β-cyclodextrin (βCD), 2-hydroxypropyl-β-cyclodextrin (HPβCD) and methyl-β-cyclodextrin were study. Results and discussion: The formation of an aqueous soluble inclusion complex was confirmed for βCD and HPβCD with a 1:1 stoichiometry. The βCD/caffeic acid complex showed higher stability than HPβCD/caffeic acid. Caffeic acid antibacterial activity was similar at pH 3 and pH 5 against the three bacteria (K. pneumoniae, S. epidermidis and S. aureus). Conclusions: The antibacterial activity of the inclusion complexes was described here for the first time and it was shown that the caffeic acid activity was remarkably enhanced by the cyclodextrins encapsulation.