Abstract: The effects of extraction pressure,extraction temperature and extraction time on the extraction rate and terpene content of pine needle essential oil from fresh Korean pine needles were studied by single factor experiment.Response surface analysis was carried out at 3 factors and 3 levels with extraction pressure,extraction temperature and extraction time as the response factors and extraction rate and relative content of terpenes of pine needle essential oil as the response values.Results show that supercritical CO₂ extraction of pine needle oil optimum process conditions for:extraction pressure 12 MPa,extraction temperature 44 ℃,extraction time 1.7 h.Under these conditions,the pine needle oil extraction yield of 1.71%±0.092%,terpene relative content was 72.38%±1.14%,consistent with the predicted value.The constituents of pine needle essential oil were analyzed by GC-MS,and 48 compounds were identified,accounting for 92.21% of the total extract.The main components are cubeb oil terpenes,isohornene,caryophyllene and other compounds.

Key words: supercritical CO₂ extraction, pine needle essential oil, response surface method, extraction yield., relative terpene content