Abstract: In order to study the content,composition and biological activities of volatile components from Poria with hostwood,the volatile components weas extracted by the method of supercritical carbon dioxide.The extraction technology was optimized by response surface method based on the single factor test,with the extraction rate of volatile as an index and three factors investigated which contained pressure,temperature and carbon dioxide flow rate.The chemical compositions were analyzed by gas chromatography-mass spectrometry (GC-MS).Also the antibacterial activities of the volatile to 5 strains of fungi were studied by the method of plate growth rate.As a result,the best extraction conditions were as follows:extraction pressure of 27.26 MPa,extraction temperature of 55.97 ℃ and carbon dioxide flow rate of 10.68 L/min.Totally 17 main compounds were identified by NIST14 mass spectral library retrieval,and the relative content was determined with the peak area normalization method,which was up to 84.5% of the volatile oil.The antibacterial experiment showed that the volatile oil had bioactivities to Coriolus versicolor.

Key words: Poria with hostwood, volatile constituent, extraction process, bioactivities