Volatile oils were extracted from lotus leaves using simultaneous distillation extraction (SDE). Volatile components in lotus-leaf extract were enriched through a purge and trap-thermal desorption (P&T-TD) method, and analyzed qualitatively with gas chromatography-mass spectrometry (GC/MS), which were comparative by analyzed with the method of direct injection GC/MS simultaneously. Totally 84 organic compounds were successfully separated and checked out with the two methods, including the organic acids, esters, aldehydes, alcohols, phenols, alkanes, aromatic hydrocarbons, olefins, and other compounds with miscellaneous atoms of nitrogen, sulfur, or oxygen, in which 63 compounds were checked out with P&T-TD GC/MS, while 41 compounds with direct injection GC/MS, and 20 compounds in common with the two methods. Comparison analysis showed that the process of P&T-TD could enrich analyzed components so P&T-TD GC/MS could check out minimal components or more volatile/semi-volatile components. P&T-TD GC/MS is a more suitable method to analyze volatile components, such as essential oils.

Key words: purge and trap-thermal desorption, gas chromatography-mass spectrometry, lotus leaf, volatile oil