Objective:To establish the contents determination method of( - ) -menthone,menthol,
cinnamic aldehyde in Po Sum On oil by
capillary column gas chromatography. Methods: 10 active components were separated and identified on HP - INNOWAX capillary column ( Crosslinked Polyethylene Glycol ,0. 25 μm × 0. 25 mm × 30 m) by GC - MS. Three constituents were determined on HP - FFAP capillary column( Crosslinked Polyethylene,0. 25 μm×0. 25 mm×30 m)by GC. The column temperature was rose by program, 115℃-155℃(1 min)-230℃ (4 min). Split injection,split ratio 40: 1;injector temperature 180℃ ;detector;FID,temperature 250℃. Results:The three constituents had good resolution. The linear ranges of ( - ) - menthone,menthol,
cinnamic aldehyde were;0. 83 - 4. 16μg,2. 52 - 12. 60μg,0. 20 - 1. 00μg with the correlation coefficients 0. 999 9 ,0. 999 9 ,0. 999 9 respectively. The RSD in the reproducibility test was less than 1. 5% (n =6). The average recoveries of ( - ) - menthone, menthol, cinnamic aldehyde were 99. 18% ,RSD = 1. 4% ;99. 92% ,RSD = 1.1% ;99. 22% ,RSD = 1. 4%. Conclusion: The method is simple, accurate and highly sensitive and is suitable for preparations which contain essential oil.