Optimization of ultrasonic-assisted extraction of continentalic acid from the root of Aralia continentalis by using the response surface methodology

In order to optimize the extraction conditions of continentalic acid, the main compound from Aralia continentalis root, we developed a model using the response surface methodology. The continentalic acid yield was analyzed and quantified by high-performance liquid chromatography coupled with UV detection. The extraction solvent, temperature, and time the three main factors for ultrasound-assisted extraction were optimized using the central composite design. Analysis of variance showed a good model fit (R2 = 0.9323). The maximum extraction of continentalic acid obtained experimentally was 1.0138 % under an extraction temperature of 33 °C and extraction time of 28 min when 100 % ethanol was used as the solvent. The experimental value was in good agreement (the yield 1.0103 %) with those predicted values. The results clearly showed that quality by statistical design could be effectively applied to optimize extraction of continentalic acid.