The flask was shaken for 15 min manually. The flask was then subjected to sonication for 15 min. The resulting solution was centrifuged at 4000 rpm for 10 min. 0.2 mL of the supernatant was diluted with methanol in a 10 mL volumetric flask to give a concentration of 20 lg/mL. The content of curcumin in emulsion was calculated using the following equation: