Based On Chromatography-mass Spectrometry Technology Research Chemical Constituents Of Cyclocarya Paliurus Leaf

Cyclocarya paliurus,an unique rare plant in China which belongs to the Juglandaceae family is mainly used for clearing heat,alleviating a swelling,relieving pain.In recent years,the research of Cyclocarya paliurus by most of the focus on the separation,identification and biological activity of small molecules substances has begun to turn to the larger molecular weight components or complex ingredients such as polysaccharide,saponins,alkaloids,etc.In this paper,SPME-GC-MS and UPLC-QTOF-MS/MS were used for qualitative analysis of volatile components and phenolic acid extracts from Cyclocarya paliurus leaf,and the main phenolic acids were determined by LC-QqQ-MS.In addition,different polar solvents were used to extract the total phenolics,total flavonoids,total sugar and antioxidant activity,and the antioxidant components was determined by UPLC-QTOF-MS/MS.The main results are as follows:Chapter 1: This paper introduces the research of the chemical composition,separation,biological activity of Cyclocarya paliurus at home and abroad in recent years.Then it briefly summarizes the present situation of the extraction technology and analysis method of chemical constituents in Cyclocarya paliurus,and the advantages of liquid chromatography mass spectrometry in the analysis of chemical constituents in plants were described.Chapter 2: Solid-phase microextraction(SPME)coupled with gas chromatography-triple quadrupole mass spectrometry(GC-QQQ-MS)was used for the analysis of volatile components in wild(Xiushui,Jiangxi)and cultivated(Wencheng,Zhejiang)Cyclocarya paliurus leaves.Then their differences in species and contents of volatile chemical compositions between groups were compared.Results showed that a total of 91 volatile constituents were identified in the Cyclocarya paliurus leaves from two region,of which 44 volatile compounds were shared in both groups.Meanwhile,it revealed that these 91 components mainly belonged to hydrocarbons,alcohols,aldehydes,esters,ketones,naphthalenes and ethers.However,there were certain differences in the specific composition and content of these volatile components in two groups.For example,the major volatile compounds of wild Cyclocarya paliurus leaves were ?-selinene(18.52%),caryophyllene(8.11%),?-bisabolene(6.01%),?-elemene(5.36%),cis-geranylacetone(4.02%),etc,while the major volatile compounds of cultivated Cyclocarya paliurus leaves were ?-bourbonene(11.05%),?-selinene(10.91%),caryophyllene(7.03%),benzyl alcohol(7.01%),2,6,11-trimethyldodecane(5.16%),2,6-dimethyl-6-(4-methyl-3-pentenyl)-bicyclo[3.1.1]hept-2-ene(5.36%),etc.Chapter 3: Using UPLC-QTOF-MS/MS to qualitative analysis of chemical composition in Cyclocarya paliurus phenolic acid extracts,and using LC-QqQ-MS for determining the content of six kinds of phenolic acids,namely,gallic acid,protocatechuic acid,p-hydroxy benzoic acid,caffeic acid,p-coumaric acid and ferulic acid.Results showed that the soluble phenolic acid extract identified 22 kinds of chemical components,including 3 organic acids,9 phenolic acids,4 flavonoids,3 esters and 3 other compound,while bound phenolic acid extract identified a total of 26 compounds,including 8 kinds of organic acids,8 kinds of phenolic acids,4 kinds of flavonoids and 6 other compounds;Mainly hydroxycinnamic acids content in cyclocarya paliurus leaf is higher while hydroxybenzoic acids content is less,and soluble phenolic acids content is greater than bound phenolic acids content,of which caffeic acid showed the highest content which were 583.61 ug/mg and 195.52 ug/mg respectively.Chapter 4: Total phenolics content(TPC),flavonoids content(TFC),sugar content(TSC)and antioxidant activities including 1,1-diphenyl-2-picrylhydrazyl(DPPH)radical scavenging activity,reducing power,total antioxidant capacity and Fe2+ chelating ability of Cyclocarya paliurus leaves(CPL)which were extracted by different solvents including water,70% ethanol,ethyl acetate and n-hexane were determined by colorimetry.This study was to investigate the correlation between phenolics contents and antioxidant activities,and the main bioactive constituents were identified by using UPLC-QTOF-MS/MS.The results showed that there were significant differences of TPC,TFC,TSC and antioxidant activities among different extracts,and the extract of 70% ethanol showed the highest TPC which could reach 219.01 mg GAE/g,so as TFC whose content was 7.23 mg CE/g,and also the strongest DPPH radical scavenging ability which reached 35.46 mg TE/g.There existed positive correlations between TPC,TFC and DPPH radical scavenging ability,reducing power,whereas the correlations between TPC,TFC and total antioxidant capacity was negative,which indicates that polyphenols played an impotant contribution to the antioxidant activities of CPL extracts.The extracts which were extracted by 70% ethanol were analysed by UPLC-QTOF-MS/MS,and 22 compouds including 8 triterpen saponins,5 flavonoids,4 phenolic acids,3 esters and 2 organic acids were identified,among them,phenolic acids and flavonoids were suggested to be the major antioxidant constituents,while others might be potential antioxidant components.