Study On The Chemical Constituents From The Rhizome Of Imperata Cylindrica Beauv.var.major(Nees) C.E. Hubb.and Their In Vitro Anti-inflammatory Activity

Imperata cylindrical Beauv.var.major（Nees）C.E.Hubb.belongs to Imperata genus,Gramineae family.The rhizome of it is sweet in taste and cold in nature.It has the functions of cooling blood,hemostasis,clearing heat and diuresis.It is mainly used in the treatment of febrile diseases,such as thirst,hematemesis,hematemesis,lung heat,dyspnea,adverse urination,edema and jaundice.As a common Chinese herbal medicine,the rhizome of I.cylindrical is rich in triterpenoids,steroids,flavonoids,acetophenone,lignin,phenylpropanoid,coumarin,phenolic acid and other chemical constituents.Pharmacological studies have shown that it has many activities such as anti-oxidation,anti-inflammation and anti-tumor.Varieties of preparations used it as the raw material,such as Baimaogen decoction,Jiawei Maogen Ercao decoction,Jiawei Baimaogen decoction,Baimaogen granules,Sancao decoction,Zicao Maogen decoction,Shenyan Kangfu tablet,which have a good therapeutic effect on acute and chronic nephritis,hepatitis A,B,C and acute jaundice in children in clinical.However,due to the lack of systematic research on it,the effective substances have not been clear.This restricts its further development and utilization.In the thesis,a systematic study on the chemical constituents and in vitro anti-inflammatory activity of I.cylindrical rhizome was conducted to lay a foundation for the further development and utilization of this medicine.Various chromatographic technologies including silica gel,ODS,Sephadex LH-20column chromatorgraphies and preparative HPLC chromatorgraphy（p HPLC）,kinds of spectrophotometric technologies such as UV,IR,¹H NMR,¹³C NMR,¹H ¹H COSY,HSQC,HMBC,NOESY,MS,and ECD,as well as chemical reaction method were combined to use to carry out the systematic chemical constituents study on the 70%Et OH extract of I.cylindrical rhizome.As results,62 compounds including 12 new isolates（1–12）and 50known ones（13–62）were obtained and identified.The 12 new compounds were named as imperphenoside A（1）,imperphenols B（2）and C（3）,imperphenosides D–F（4–6）,imperlignanosides A–E（7–11）,and5-Hydroxy-8-O-β-D-glucopyranosyl-2-（2-phenylethyl）chromone（12）,respectively.Moreover,among the 50 known ones,4-hydroxy-3-methoxy phenyl-β-D-xylopyranosyl（1→6）-O-β-D-glucopyranoside（13）,cuneataside D（14）,3,4-dimethoxyphenyl-β-D-glucopyranoside（15）,3,4-dimethoxyphenyl-1-O-β-D-apiofuranosyl（1→6）-β-D-glucopyranoside（16）,3,4,5-trimethoxyphenyl1-O-β-apiofuranosyl（1’’→6’）-β-glucopyranoside（18）,2’-O-（E）-p-coumaroylsalicin（20）,poliothrysoside（21）,salireposide（22）,4’-hydroxybenzyl-2-hydroxybenzoate-1’-O-β-D-glucopyranoside（23）,syringic acid（29）,glucosyringic acid（30）,echipuroside A（31）,ethyl caffeate（34）,coniferaldehyde（35）,ferulic acid（36）,（+）（7S,8S）-guaiacylglycerol（37）,（+）-（7S,8S）-guaiacylglycerol8-O-β-D-glucopyranoside（38）,（7S,8S）-syringoylglycerol（39）,（7R,8R）-4-O-methylsyringoylglycerol（40）,1,2’,4’,6’-tetraacetyl-3,6-diferuloyl-sucrose（41）,sucrose diester of 4,4’-dihydroxy-3,3’-dimethoxy-β-truxinic acid（42）,（–）-syringaresinol-4-O-β-D-glucopyranoside（43）,（6R,7S,8S）-7α-[（β-glucopyranosyl）oxy]lyoniresinol（44）,5,2’-dimethoxyflavone（47）,tricin4’-O-（erythro-β-guaiacylglyceryl）ether（48）,tricin 4’-O-（erythro-β-4-hydroxyphenylglyceryl）ether（49）,6-hydroxy-2-（2-phenylethyl）chromone（51）,3-O-caffeoylquinic acid methyl ester（54）,（–）-4-O-feruloylquinic acid methyl ester（56）,（6R,9S）-13-nor-5-carboxyblumenol C9-O-β-glucoside（58）,（6S,9S）-roseoside（59）,（1R,2S）-2-hydroxycyclohexyl-2’-O-trans-p-coumaroyl-β-D-glucopyranoside（61）,and glycerol-1-O-α-D-glucuronide 3-O-benzoyl ester（62）were firstly obtained from Imperata genus.Meanwhile,theconfigurationofsucrosediesterof4,4’-dihydroxy-3,3’-dimethoxy-β-truxinic acid（42）was determined firstly by using ECD method.An in vitro anti-inflammatory activity screening model using lipopolysaccharides（LPS）-induced RAW 264.7 cells was established to evaluate the NO inhibitory effects of the components isolated and identified from the rhizome of I.cylindrica.The results indicated that phenolic components（4,13,14,26,29,33,34,39,45,47,49–51,55,and 56）exhibited anti-inflammatory activity,and the activity was in concentration-dependent at 3,10,and 30μM.The structure-activity relationships of phenylpropanoids,phenolic acids,flavonoids and quinic acids were summarized as well.In the thesis,the chemical constituents in the rhizome of I.cylindrical were enriched through systematical study,which would lay a foundation for its further research and development in quality control and pharmacodynamics.In addition,the in vitro anti-inflammatory activity assay carried out on this basis provided a reference for the further application of I.cylindrica in the research and development of new anti-inflammatory drugs.