Impact of extraction parameters on chemical composition and antioxidant activity of bioactive compounds from Chinese licorice (Glycyrrhiza uralensis Fisch.) by subcritical water

An efficient extraction of bioactive compounds from licorice was developed using subcritical water. This study aimed at investigating the impacts of parameters on the composition and antioxidant property of the extract. It was found that total phenolics (TP), total flavonoids (TF), glycyrrhizic acid (GL), and antioxidant activity (TAA) were significantly affected by the time, pH, and temperature. The parameters of 20 min and pH 8 were preferred. The maximum values were obtained at 200 degrees C (TF, TP), and 140 degrees C (GL). At 280 degrees C, TAA reached the highest level. Subcritical water extraction was confirmed to be an environmentally-friendly and efficient method.