Abstract: The volatile oil of Radix ophiopogonis was extracted by supercritical carbon dioxide.Single factor experiment and orthogonal design were used to study the influences of extraction conditions on the yield of volatile oil. The optimum extraction parameters of 100 g R.ophiopogonis were established with extraction pressure of 30 MPa, extraction temperature of 55℃, flow rate of CO₂ at 14 kg/h, and the extraction time of 1.5 h. The optimum technology for supercritical CO₂ extraction of volatile oil from Radix ophiopogonis was high efficient, and the yield of volatile oil was up to 0.31%.

Key words: Radix ophiopogonis, supercritical CO₂ extraction, volatile oil