Analysis Of Volatile Compounds In Cyperus Rotundus Tubers By A Solid-Phase Extraction Element Combined With Headspace Extraction And Thermal Desorption-Gas Chromatography/Mass Spectrometry

Cyperus Rotundus tubers,one of Traditional Chinese medicines(TCMs),was the dry tubers of Cyperaceae.It is a well-known medicine for the treatment of dysmenorrhoea and menstrual irregularities.Quality monitoring of Cyperus rotundus tubers can be performed by gas chromatography(GC) or gas chromatography/mass spectrometry(GC/MS) after the extraction of the essential oil by Steam Distillation(SD), Solvent Extraction and Solid Phase Microextraction(HS-SPME).In this study,a novel solid-phase extraction element named "MC’ combined with headspace extraction and thermal desorption(TD) -gas chromatography/mass spectrometry(GC/MS) using a pyrolysis-GC/MS system was applied for the analysis of volatile compounds in Cyperus rotundus tubers.Headspace MC extraction-TD-GC/MS was applied for the study of volatile compounds in Cyperus rotundus tubers from Zhejiang Province.TD,MC extraction and GC conditions were optimized.Under the selected condition,55 peaks were detected and 30 compounds were signed which accout for 92.3%of total peak area.The main volatile compounds were cyperene(22.9%),rotundene(4.3%),β-selinene(11.4%), selina-4,11-diene(4.2%),β-cyperone(13.7%) andα-cyperone(11.0%).SD-GC/MS and SPME-GC/MS were also applied for the study of volatile compounds in Cyperus rotundus tubers from Zhejiang Province.Their results were compared with those of MC extraction.The number of the compounds identified by SD, SPME and MC methods were 32,31 and 25,respectively.In comparison with SD method,MC show more powerful to extract some low volatility compounds.Compared with SPME,the peak abundance of all compounds extracted by the MC methods is higher than that by SPME and 5 more compounds were extracted while half sample mass were used.indicating that MC extraction methods have a potential use in precious kind of TCM analysis.Lastly,the fingerprints of 12 Cyperus Rotundus tubers samples from 3 different origins were obtained by headspace MC extraction-TD-GC/MS based on the relative peak areas of 44 peaks in each GC profiles.12 samples were also analysis by pattern recognition methods-Hierarchical Cluster analysis,showing that sample from Zhejiang and Anhui Province classfied into 2 groups.Thus,the results proved that headspace MC extraction-TD-GC/MS method was uses much less sample and afforded a higher yield of total compound.As a conclusion, headspace MC extraction-TD-GC/MS is a rapid,convenient,effective and solvent-free method suitable for the analysis of volatile compounds from Cyperus Rotundus tubers.