Antibacterial Activity of Curcumin and Solubility-Enhanced Curcumin in Microemulsion: a Comparative Study

The current study focus was to develop a microemulsion delivery system for curcumin and solubility-enhanced curcumin inclusion complex and compare the antibacterial activity of curcumin with solubility-enhanced curcumin in dimethyl sulphoxide first and later in microemulsion formulation. Solubility studies of curcumin in different oils, surfactants and co-surfactants were performed. The pseudoternary phase diagram was constructed using water titration method. All the selected microemulsion formulations loaded with curcumin and curcumin-cyclodextrin inclusion complex were prepared and characterized for pH, conductivity, viscosity, particle size, zeta potential. Agar well diffusion method was used for antibacterial studies against Staphylococcus aureus and Escherichia coli. Curcumin showed higher solubility in isopropyl myristate as oil, tween 80 as surfactant and polyethylene glycol 400 as cosurfactant and pseudo-ternary phase diagram was constructed successfully. Microemulsion delivery system was more effective and suitable for the delivery of Curcumin and solubility-enhanced Curcumin-inclusion complex than dimethyl-sulphoxide with enhanced antibacterial activity.