The Extraction And Chemical Compositions Analysis Of C.citratus Essential Oil

C.citratus Stapf is a Cymbopogon Spreng species living in tropical and subtropical areas.In our country,it is mainly distributed in Guangdong province,Hainan province,Fujian province,Yunnan province,et al.Essential oil Extracted from the C.citratus.contains a variety of active ingredients,including aldehydes,alcohols,esters and allyl terpenoids,et al.Due to these active ingredients,the essential oil from C.citratus has antibacterial,antioxidant and anti-tumor efficacy.It has a broad future in daily productin and medicine&health.Currently,the traditional extraction method is mainly used in extracting essential oil from C.citratus and the yield of the essential oil is very low.In addition,the growing geographical and climatic conditions can also affect the active ingredient C.citratus essential oil.Building the common fingerprint model has great significance for C.citratus essential oil in quality control and origin identification.In this study,the conditions of supercritical CO2 extraction and microwave extraction to extract C.citratus essential oil was optimized to improve the yield of C.citratus essential oil;The GC/MS technology was used to analysis the chemical composition of C.citratus essential oil.Compared the chemical composition of different oil samples,which were obtained by different extraction methods,from different extraction parts and different leaf ages;Given the growth of geographical environment and climate conditions can influence the chemical composition of C.citratus essential oil,C.citratus from Guangdong province,Hainan province,Fujian province and Yunnan province were chosen as the research object,in this topic,to build the common fingerprint model of C.citratus essential oil from different regions.The main results were listed as follows:Supercritical CO2 extraction optimized On the basis of single factor experiment,the best extracting conditions were determined as followed:analytical pressure was 3.0 MPa;analytical temperature is 30?;the range of extracting time was 80?100 min;the range of extracting pressure was 22-28MPa;the range of extracting temperature was 32?38 ?;the range of CO2 flow was 16?20L/h.The Box-Behnken experiment was designed to optimize the extracting conditions.it was concluded that the best extracting time was 120 min,extracting pressure is 25 MPa,extracting temperature 35? CO2 flow was 18 L/h.By three parallel tests,the experimental was very close to predicted values and the C.citratus essential oil yield was(4.32±0.06)%.Compared with the predicted values of the optimal estimation regression equation fitting,the error was 0.91%.As a result the yield of C.citratus essential oil increased by 3.59%.Microwave extracting conditions optimizated By single factor experiments,anhydrous ethanol was chosen as the extraction solvent,the best ratio of material and liquid was 1:20;the best extracting conditions were determined as followed:the range of extracting time was 6,5?7.5 min,the range of extracting power was 375?425W,the range of extracting temperature was 52?58?.The extracting condition was optimized by orthogonal experiment design and analysis software.It was concluded that the best extracting time was 7 min;the extracting power was 375W;the extracting temperature was 55?.In parallel test,the optimized extracting condition was used to extract C.citratus essential oil.As a result the optimized yield of C.citratus essential oil was(3.20±0.08)%,which was increased by 2.89%.The chemical composition analysised of C.citratus essential oil 39 kinds of compositions were identified from the C.citratus essential oil extracted by steam distillation;44 kinds of components were identified from the C.citratus essential oil extracted by supercritical CO2 extraction;36 kinds of components were identified from the C.citratus essential oil extracted by microwave extraction.From the essential oil of C.citratus,40 kinds of components were separated and identified;from the essential oil of C.citratus,26 kinds of components were separated and identified;from the essential oil of C.citratus roots,26 components were separated and identified.39 kinds of components were detected from the essential oil of C.citratus old leaves and 18 kinds of components were detected from the young leaves of the same strain.On the analysis of the 8 kinds of C.citratus essential oil samples,citral(neral and geranial),geraniol,ea It compositions were high.The fingerprint chromatogram of C.citratus essential oil established Essential oil extracted from Guangdong province,Hainan province,Fujian province and Yunnan province were analysised and detected by GC-MS method.The results were analysised and calculated by the similarity evaluation system software of Chinese-medicine spectral fingerprint(Similary system for chromatographic fingerprint of TCM "Version 2004A")recommended by the state drug administration.The common pattern of fingerprint chromatogram of C.citratus essential oil was established.The similarity between the fingerprint chromatogram of samples and common pattern of fingerprint chromatogram were greater than 0.900,which was conformed to requirements of the state drug adminstration for fingerprint similarity.