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In this review, the concept and idea of chemical modeling and model population analysis ( MPA) were introduced, and the recent applications of MPA-based methods to different aspects of chemical modeling were listed, including outlier detection, variable selection, model evaluation and applicability domain. In addition, the feasibility and applicability of MPA to different kinds of dataset was illustrated, such as near infrared spectroscopy, quantitative structure-activity relationship and metabolomics, which provided a better idea and framework to develop a new algorithm in chemical modeling.
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<p><b>OBJECTIVE</b>To identify and quantify the compound compositions of ether extracts of Ligustrum lucidum.</p><p><b>METHOD</b>After extracted 4 hour by Soxhlet extraction with ether, the extractive were analyzed by gas chromatography and mass spectrometry (GC-MS). Furthermore, heuristic evolving latent projection (HELP) was used to resolve the overlapping peaks to obtain the pure concentration profiles and mass spectra. Subsequently, mass spectral similarity search combining with the retention index was employed for the identification of each component.</p><p><b>RESULT</b>Totally, 75 compounds were identified, accounting for 84.3% of that in the whole ether extracts of L. lucidum.</p><p><b>CONCLUSION</b>The main compounds of L. lucidum are oleic acid, lupeol and (Z,Z) 9,12-octadecadienoic acid, whose relative content were 9.805%, 8.848%, 8.357%, respectively.</p>
Subject(s)
Ether , Chemistry , Gas Chromatography-Mass Spectrometry , Methods , Ligustrum , Chemistry , Plant ExtractsABSTRACT
<p><b>OBJECTIVE</b>To study the chemical constituents from the stems of Zanthoxylum dissitum.</p><p><b>METHOD</b>Column chromatography on macroporous resin and silica gel, and spectral analysis were used to isolate and elucidate the constituents.</p><p><b>RESULT</b>Seven compounds were isolated and identified as 5,8-dimethoxyethane-3,4-epoxy-furanocoumarin (1), isoimpinellin (2), beta-sitosterol (3), lupeol (4), neohesperidin (5), beta-daucosterol (6), ursolic acid (7).</p><p><b>CONCLUSION</b>All above the compounds were isolated from the plant for the first time and the compound 1 is a new compound.</p>
Subject(s)
Drugs, Chinese Herbal , Chemistry , Plant Stems , Chemistry , Zanthoxylum , ChemistryABSTRACT
OBJECTIVE:To establish a GC-MS method to identify the volatile constituents in Radix Isatidis.METHODS:The method of wet distillation was applied to extracting volatile oil from Radix Isatidis,the chromatographic column was OV-1,and the flow rate was 1.0mL?min-1,EI ion source was used by MS.The volatile constituents in Radix Isatidis were identified and analyzed by NIS107 system.RESULTS:22 chromatographic peaks were separated,19 chemical compounds were identified,representing 90.51% of total amount,hexadecanoic acid had highest content,accounting for 38.52% of total amount.CONCLUSION:This experiment has provided initial usable data for comprehensive utilization of Radix Isatidis.
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AIM To detect chemical components of the essential oil of Schisandra chinensis(Turcz.)Baill.. METHODS The essential oil was analyzed with GC/MS, heuristic evolving latent projections(HELP) resolution and overall volume integration method. RESULTS HELP method along with the data from GC/MS can be used to conduct the peak purity examination and resolution of overlapping peaks to obtain pure chromatogram and MS spectrum of each component. Fifty six components were separated and 49 of them were qualitatively and quantitatively analyzed. All the components represent about 98.27% of the total content. CONCLUSION The resolved pure chromatogram and MS spectrum can greatly enhance the reliability of similar searches in the commercial MS database and thus contribute to the accuracy of the qualitative and quantitative analysis of the essential oil.
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Objective To establish the standard of quality control for Pericarpium Citri Reticulatae Viride (PCRV) and to identify two kinds of PCRV which are collected in different times. Methods In this article,volatile components and flavonoid in 10 batches of samples which were collected from eight provinces were determined by GC and HPLC-DAD,respectively. Their fingerprints were handled by weighted similarity of range and by principal component analysis (PCA). Results According to the result of similarity and classification,there were obvious differences between the two kinds of PCRV.To know whether the differences have great influences on the pharmacological actions of PCRV, pharmacological studies will be needed. Weighted similarity is suitable for this system which has a high content of similar components. Conclusion These methods are effective and will help us to establish the criterion of quality control for PCRV.
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Objective To compare the difference in constituents from different parts of wild and cultivated Ephedra sinica. Methods Using the solvent of 50% methyl alcohol to extract from the stems and roots of wild and cultivated E. sinica under heating reflux, respectively and then determine the content of ephedrine in each extractions by HPLC. The volatile oil was extracted by stream-distillation and analyzed by GC-MS method. Results The content of the ephedrine in extraction of stems and roots of wild E. sinica was 0.55% and 0.000 57% while the content of the cultivated was 0.26% and 0.001 7%. Forty-five compounds in the volatile oil were identified by GC-MS method, among them 13 compounds existed in both wild and cultivated E. sinica. Conclusion The content of the ephedrine is about two times of the cultivated in wild E. sinica′s stems, while it is very low in the roots of two kinds of herbs. And ephedrine is not found in the volatile oil.