| Mgnoliae Flos,originally recorded at Shennong's classic of Materia Medica,is the dried flower bud of Magnolia biondii Pamp.,Magnolia denudata Desr.or Magnolia sprengeri Pamp.From the perspective of Traditional Chinese Medicine,Flos Mgnoliae is warm-natured and can be used in the treatment of chill,headache,nasal tampon,allergic rhinitis and nasosinusitis.The main bio-active components in Flos Mgnoliae includes volatile and non-volatile compounds,and the non-volatile ones contains lignans,flavonoids and alkaloids.According to the pharmacodynamics studies both volatile and non-volatile components contribute to the holistic pharmacological effects of Flos Mgnoliae.For non-volatile components,although there are many reports related to isolation and bio-activity experiments,studies focused on chromatographic separation and online detection as well as quality control and pharmacokinetics are not sufficient.The proposed study,mainly based on liquid chromatography and tandem mass spectrometry as well as improved algorithm in fingerprint analysis,aimed to the identification,isolation and preparation,fingerprint analysis and pharmacokinetic study of components in M.biondii.1.Identification of chemical and absorbed components in Magnolia biondii Pamp.by high-performance liquid chromatography-ion trap/ time of flight mass spectrometryIn this chapter,HPLC was applied for the separation of components in M.biondii,and 17 components were identified according to the fragmentation information provided by IT MS and accurate molecular weight provided by TOF MS,as well as reference to the literature and analysis of reference substances,including one alkaloid,one coumarin,two flavonoids and thirteen lignans,with their fragmentation pathways illustrated.Furthermore,ten lignans were identified as absorbed by SD rats by analysis of plasma and urine samples after administration of M.biondii extracts.The HPLC-MS based qualification study of components in M.biondii extracts could provide information for fingerprint analysis and pharmacokinetic study.2.Preparation of seven lignans from M.biondii by high-speed counter-current chromatography coupled with preparative high-performance liquid chromatographyIn previous chapter,the absorption of 10 lignans in SD rats has been identified,among which seven kinds of parallel double furan type lignans contributed to the holistic pharmacological effects of M.biondii according to the literature,with limited ones commercially available.Previous approaches usually involved repeated silica gel chromatography,which is tedious and time-consuming.In this chapter,HSCCC coupled with PHPLC were applied for the preparation of seven lignans from M.biondii.The solvent system in HSCCC was optimized as n-hexane-ethyl acetate-methanol(0.8% ammonium acetate)-water(0.8% ammonium acetate)with the ratio of 24:16:21:19 according to the physiochemical property,partition coefficient of target analytes,retention rate of stationary phase and separation performance in analytical HSCCC.The optimized solvent system was then applied to the preparative HSCCC for the isolation of components in M.biondii into three fraction.Condition for PHPLC were optimized according to the differences of target analytes and impurities in each fraction,respectively.For fraction 1,36% acetonitrile was selected as mobile phase,with small injection volume(60 ?L)and short injection interval(7 min).For fraction 2,38% acetonitrile was selected as mobile phase,with small injection volume(50 ?L)and medium injection interval(25 min).For fraction 3,38% acetonitrile was selected as mobile phase,with large injection volume(500 ?L)and long injection interval(50 min).The proposed method was stable with the product of high purity,and could provide material basis for quality control and pharmacokinetic study of M.biondii.3?fingerprint analysis of M.biondii based on modified algorithm of Similarity AnalysisThe quality control of Traditional Chinese Medicines involves assessment of multiple components,thereby the fingerprint analysis is widely applied in the quality study and quality standard of TCM.The Chinese Pharmacopoeia Commission had released the Similarity Evaluation System for chromatographic fingerprints of Traditional Chinese Medicines in 2004 and 2012,in which the Similarity Analysis approach was widely used in fingerprint analysis of TCMs.However,in some cases the result of SA differed from those from other chemometric approaches such as Principle Component Analysis and Hierarchical Clustering Analysis,and those from the quantitative analysis.Based on these problems,a modified SA approach was proposed in this chapter.The chromatographic fingerprint of M.biondii was established based on analysis of 17 batches of M.biondii extracts obtained by pressurized solvent extraction.Original and modified SA as well as PCA and HCA were performed and compared to illustrate the advantages of modified method over the original one.Chemical quantitative markers were then selected based on modified SA and PCA approaches,and the method for quantitative analysis of multi-components by single marker based on Charged Aerosol Detection was established and applied for simultaneous determination of nine components in M.biondii,and the results were compared with those from original and modified SA to confirm the improved discriminative capacity of modified method over the original one.The proposed approach was finally validated by external data from literature.In this study,a modified SA method was proposed and applied to the quality control of M.biondii,which provided reference for the quality study of other TCMs and their preparations.4?Determination of seven lignans in plasma from rat and beagle dog and its application in pharmacokinetic studyPharmacokinetic study focuses on the biological effect from body to drugs including absorption,distribution,metabolism and excretion.The purpose of Pharmacokinetic study is to demonstrate the in vivo process and provide reference to the clinical administration of drugs for safety and efficacy.In this chapter,the HPLC-MS/MS approach for quantitative analysis of seven lignans in plasma of rats and dogs was developed based on previous study including the screening of absorbed components and the preparation of seven lignans.The performance of the proposed method including precision,accuracy and stability was validated.The validated method was then applied to the pharmacokinetic study of seven lignans in SD rats and beagle dogs. |
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