Lavender Volatile Composition Analysis And Its Quality Control

In this thesis, L. angustifolia and L. dentate were extracted by hydrodistillation(HD) and headspace solid-phase microextraction, and their compounds were analysisby GC/MS. The species were also identified by principal components analysis (PCA)and Hierarchical cluster analysis (HCA). The main results are as follows:1.(a) The essential oils of the ten Lavandula angustifolia (L. angustifolia)samples (from China) and ten Lavandula dentate (L. dentate) samples (from Pakistanand India) were obtained by HD and investigated by gas chromatography/flameionization detector (GC/FID) and gas/chromatography/mass spectrometry (GC/MS).A total of83compounds were identified from ten L. angustifolia samples, while63compounds were identified from L. angustifolia samples, which contain a higher levelof linalool and linalyl acetate but little camphor, were evaluated as the higher qualitybetween the two Lavandula species. The data obtained by the analysis of volatilecompounds, according to the proposed method, were treated with PCA and HCAchemometrics tool in order to classify the samples of L. dentate and L. angustifoliawith their volatile compounds.(b) A headspace solid-phase microextraction (HS-SPME) method followed byGC and GC/MS was described for the analysis of volatile compounds in L. dentateand L. angustifolia. Four types of SPME fibers were investigated and the bestextraction was achieved with the mixed fiber DVB/CAR/PDMS. Parameters forHS-SPME including desorption time, extraction time and temperature were alsoinvestigated. The L. dentate and L. angustifolia samples were extracted under theoptimized conditions to obtain their volatile compounds. And the data obtained by theanalysis of volatile compounds were treated with PCA and HCA to classify thesamples of L. dentate and L. angustifolia with their common volatile compounds. Itcan be concluded that a HS-SPME/GC-MS method, combined with PCA and HCAwere able to differentiate the Lavandula species, and is a prospective methodology for identifying the differentiation of the aromatic plants.2. The essential oil compounds of the flowers, leaves and stems of the Lavandulaangustifolia was extracted by HD and HS-SPME, and were analyzed by GC-MS. Theresults show that, the flowers of the Lavandula angustifolia have the most compoundsamong the three parts. This study carried on analysis to the chemical constituents inthe essential oil of the flowers, leaves and stems of Lavandula angustifolia, andprovided instruction for the comprehensive exploitation of medicine Lavandulaangustifolia.3. The content of the Linalool of the L. angustifolia and L. dentate wasanalysised. The results show that the Linalool in the essential oil of the L. angustifoliawas very high, but very low in the essential oil of L. dentate, and was not detected.4. The finger-print of the L. angustifolia and L. dentate were structed by GC, andanalysied their similarity. The results indicated that, the similarity of the sample spicesof the Lavandula were very high, but different species very low. So L. angustifoliaand L. dentate can be good identified by GC finger-print.5. A novel methodology for identification and differentiation of Lavandulaangustifolia and Lavandula dentate was developed based on FT-IR spectroscopy usinghierarchical cluster analysis (HCA) and principal component analysis (PCA). Theexperimental approach discriminated L. angustifolia and L. dentate100%successfully.Perfect discrimination of L. angustifolia and L. dentate, even from aromatic plants,strikingly demonstrates the potential of the method.