Optimization of Supercritical Fluid Extraction of Oil from the Fruit of Gardenia jasminoides and Its Antidepressant Activity

A response surface methodology was applied to optimize the variables affecting the supercritical fluid carbon dioxide extraction of oil from the fruit of Gardenia jasminoides using the Box–Behnken design. The optimum extraction parameters were an extraction temperature of 49.94 °C, an extraction pressure of 29.89 MPa and an extraction time of 93.82 min. Through a GC/MS analysis, we revealed 16 major components of the oil extract, which showed potent antidepressant effects in both of two behavior despair models in mice: tail suspension test and forced swimming test. Our results suggest that the oil extract of Gardenia jasminoides prepared using the supercritical fluid carbon dioxide extraction may contain effective constituents to be used for depression therapy.