Semi-continuous extraction of Agarwood oil with subcritical water: Optimization of plug flow by response surface methodology

A semi-continuous extraction of Agarwood oil with subcritical water (105-240 [degrees C], pressure 1-10 [MPa], and flow rate 1-6 [mil/min]) was evaluated and optimized by using a response surface methodology. Analysis of variance demonstrated that a quadratic regression model illustrated small synergetic effects of temperature-pressure and pressure-flow rate. The optimal conditions were temperature of 207 [degrees C], pressure of 3.7 [MPa] and flow rate of 5.69 [mL/min], obtaining a maximum yield of 14.99[9/owt]. The product obtained from the optimal condition had high yield of oil as similar as conventional extraction process while consuming dramatically shorten extraction time. This process could be considered as an innovative extraction of Agarwood oil.