Objective The variety'Yingchunsu'was used as raw material to prepare the essential oil of Cymbidium sinense, and the extraction process was optimized to improve the yield of the essential oil.Then the composition of the essential oil was analyzed.

Method The extraction conditions of C. sinense essential oil were optimized by single factor and orthogonal tests, the effects of different organic solvents, solid-liquid ratios, ultrasonic extraction time and ultrasonic extraction temperature on the yield of C. sinense were studied, and the chemical components of the essential oil were analyzed by headspace solid phase microextraction-gas chromatography-mass spectrometry (GC-MS).

Result The essential oil extracted from C. sinense by ethanol was bright in color, rich in flavor and good in taste.The optimum extraction conditions of C. sinense essential oil were as follows: with 95% ethanol as extractant, solid-liquid ratio of 1:9(g/mL), ultrasonic extraction time of 40 min, and ultrasonic extraction temperature of 50℃.Under these conditions, the yield of essential oil could reach 2.96%.A total of 78 compounds including aldehydes, alcohols, aromatic compounds, ketones, alkanes, olefins, carboxylic acids, esters and other compounds were detected in the extracted essential oil.The chemical components with high content were palmitic acid (17.37%), nonaldehyde (10.57%), n-pentadecanoic acid (8.69%), tetracosane (4.65%), alloy alcohol (4.03%) and etc.

Conclusion The quality of C. sinense'Yinchunsu'essential oil obtained by ethanol was better.By optimizing the solid-liquid ratio, the ultrasonic extraction time and the ultrasonic extraction temperature, the yield of C. sinense essential oil could be increased.The main components of essential oil were palmitic acid, nonaldehyde, n-pentadecanoic acid, tetracosane and alloy alcohol.