Studies On Chemical Constituents And Antidepressant Effect Of Different Parts From Platycodon Grandiflorum

To study the volatile and non-volatile components,antidepressant effect and mechanism and effective substances of the roots,stems,leaves and seeds of Platycodon grandiflorum(PG),some methods and techniques,such as GC-MS,LC-MS,NMR,metabolomics and serum pharmaceutical chemistry,were applied respectively in the paper.As a result,a total of 268 compounds including one new compound named Platycodynol were identified.There are 29 markers were found to profile different parts of PG by using non-targeted metabolomics.Meanwhile,it was screened that the leaves of PG showed a good anti-depressant effect as a new medicinal part.Furthermore,it was revealed that 9 endogenous metabolic pathways were related with the antidepressant effect of leaves of PG.Finally,there are 20 kinds of prototype components,which are related to the anti-depressant effect,were identified in serum.The innovative achievements obtained were listed as follows:1.The volatile components of 4 parts of PG were studied by using HS-SPME combined with GC-MS for the first time.A total of 87 volatile components were identified including 39 olefins,9 aldehydes,4 alcohols,15 esters,4 ketones,13 heterocyclic oxygen,2 phenolics and 1 acid.There are 26 components(32.4% esters,21.89% aldehydes),including 15 characteristic ingredients such as vanillic aldehyde(16.22%),were identified from roots.There are 17 components(36.19% olefins,29.11% alcohols),including 9 characteristic ingredients such as hexanol(29.11%),were identified from stems.There are 33 components(34.18% esters,25.60% olefins),including 20 characteristic ingredients such as(Z)-3-hexenyl acetate(19.21%),were identified from leaves.There are 30 components(19.60% olefins,13.06% aldehydes),including 21 characteristic ingredients such as peonol(6.68%),were identified from seeds.In addition,the types and content distribution of volatile components were compared and analyzed.The work will fill the blank for the study of volatile components in stems,leaves and seeds of PG.2.By using UPLC-QTOF-MS combined with UNIFI platform,the rapid identification of components in the roots,stems,leaves and seeds of PG were performed for the first time.There are 73,42,53 and 66 compounds identified respectively from the different parts,including triterpenoid saponins,flavonoids,steroids,etc.3.UPLC-QTOF-MS combined with multivariate statistical analysis such as PCA and OPLS-DA were used to carry on the non-targeted plant metabolomics of 4parts of PG for the first time.The results showed that there was a great difference between 4 parts of PG.There are totally 29 characteristic ingredients(9 from root,3from stems,7 from leaves,10 from seeds)were identified from PG.The characteristic ingredients in roots are platycodin A?-B?-D2?-G3 and-K,deapio platycoside E,2'-O-acetyl-platycodin D2,2?-O-acetyl-polygalacin D2 and sanleng acid.The characteristic ingredients in stems are quercimeritrin,quercetin-3-O-arabinoside and2,6-Di-O-galloyl-?-D-glucose.The characteristic ingredients in leaves are grosvenorine,7-hydroxy-1-methoxy-2-methoxyxanthone,4?,7-dimethyltectorigenin,curcolone,atractylenolide?,geraniin and 1,2,3,4,6-penta-O-galloyl-?-D-glucopyranoside.While the characteristic ingredients in seeds are isobavachin,(2R,3R)-taxifolin7-O-?-rhamnopyranosyl-(1?6)-?-D-glucopyranoside,taxifolin-3-O-glucoside,dihydrokaempferol,epiafzelechin-3-O-?-D-allopyranoside,3-hydroxynarin-genin,apigenol,?-hydroxyemodin,6-hydroxyaloeemodin and benzyl-2-hydroxy-6-ethoxyben zoate.4.A total of 45 compounds were isolated from the leaves of PG by using repeated silica gel column chromatography,Sephadex LH-20 and preparative HPLC.Among them,41 compounds were identified by using TLC,NMR and MS.They are Platycodynol(1),Platycoside E(2),Platycodigenin(3),Platycodin D3(4),Deapio-platycodin D3(5),3-O-?-D-glucopyranosyl platycodigenin(6),Deapio-platycodin D(7),Platycodin D(8),Platycodin G1(9),Polygalic acid(10),Oleanolic acid(11),Oleanonic acid(12),Hydroxy-12-oxoolean-28-acid(13),Betulin(14),?-Spinasterol(15),Stigmasterol(16),?-sitosterol(17),Daucosterol(18),Lobetyolin(19),Quercitroside(20),Scutellarin(21),Naringin(22),Rutin(23),Apigenin-7-O-?-Dglucopyranoside(24),Dihydroquercetin(25),kaempferide(26),Luteolin(27),Syringin(28),Ethylsyringin(29),Methoxyeugenol4-O-rhamnosyl-glucoside(30),Atractylenolide II(31),Diphenic acid(32),Caffeic acid(33),Gallic acid(34),Myristic acid(35),Palmitic acid(36),(2R,3R,4E)-Octadec-4-ene-1,2,3-triol(37),1,2,4-Trihydroxyheptadeca-16-ene(38),n-octadecane(39),Sucrose(40)and DFructose(41).Most importantly,compound 1 was identified as a new compound.Compounds 13,29,30,31,32,37 and 38 were obtained from Campanulaceae for the first time.5.The antidepressant effect of the roots,stems,leaves and seeds of PG were screened for the first time.Both the roots and the leaves showed the antidepressant effect.While,the effect of leaves was greater than that of roots.With the treatment of PG leaves,body weight,food intake,sugar preference,and standing scores in open field test were all increased significantly.The immobility time in FST and TST were also shortened.All of the above results indicated that leaves of PG have a significant anti-depression effect.6.The mechanism of antidepressant effect of extraction of leaves of PG(ELPG)were also explored by using metabolomics method for the first time.It was revealed that there were 9 endogenous metabolic pathways,including glycerophospholipid metabolism,sphingolipid metabolism,linoleic acid metabolism,tryptophan metabolism,TCA cycle,arachidonic acid metabolism,glutathione metabolism,pantothenate and Co A biosynthesis and inositol phosphate metabolism,maybe involved in the anti-depression effects of ELPG.7.In order to find the effective components for the anti-depression effect,the method of serum pharmaceutical chemistry was used in the study.There were 24 prototype components were identified in the serum of healthy mice for the first time.Among of them,20 components were also found in the serum of depressive model mice.Then,it was speculated that,together with the compound platycodynol,flavonoids including asrutin,delphinidin,dihydroquercetin and luteolin-7-Oglucopyranoside,may be related to the antidepressant effect.In summary,in this paper,the chemical basis of the roots,stems,leaves and seeds of PG were elucidated.The characteristic ingredients of different parts were found.ELPG were screened out to be an anti-depressive agent,and the mechanism were also explored.The components absorbed in serum were identified.The work should benefit the research of PG.Meanwhile,it will provide the scientific basis for the further development of leaves of PG,an innovative antidepressant agent.