Study On The Bioactive Constituents Of Chinese Olive (Canarium Album Rauesch.) Fruits

Chinese olive（Canarium album Rauesch.）,belongs to the family Burseraceae,which is mainly distributed in southern provinces of China,such as Fujian,Guangdong,Guangxi,Hainan,Taiwan and Yunnan.It is different genera with the Olea europaea L.used to produce olive oil.Chinese olive fruits are used as a traditional Chinese herbal medicine with a refreshing savor and the high medicinal value.According to the“Compemdium of Materia Medica”,Chinese olive fruits have a mild,sweet and sour taste,with the effect of clearing heat,relieving sore throat and detoxicating.They are usually used for treatment of cough,pharyngalgia,polydypsia and poisoning.In this study,Chinese olives were extracted with 70%ethanol-water.The concentrated solution was successively extracted by different polar solvents.The antioxidant,NO inhibitory andα-glucosidase inhibitory activities were evaluated for each fraction.The results showed that the chloroform fraction and EtOAc fraction exhibited pronounced antioxidant,NO inhibitory andα-glucosidase inhibitory activities.Therefore,these two active fractions were selected for further research.The bioactive fractions were isolated and purified by silica gel,ODS MPLC,Sephadex LH-20column chromatography and pHPLC to obtain 53 compounds,and their structures were identified on the basis of physical and chemical properties and spectral techniques.Their nomenclatures respectively named as（7R,8S）-3-hydroxyl-4-methoxyl-balanophonin（1）,（7R,8S）-3-methoxyl-4-hydroxyl-balanophonin（2）,（7S,8R）-threo-balanophonin（3）,（7S,8R）-threo-1’-[3’-hydroxy-7-（4-hydroxy-3-methoxyphenyl）-8-hydroxymethyl-7,8-dihydrobenzofuran]acrylaldehyd（4*）,curcasinlignan C（5）,（7S,8R）-threo-lycocernuaside B（6）,（7R,8S）-erythro-3-methoxy-4-hydroxy-7-methoxy-8-O-（2’-methoxy-4’-aldehyde-phenyl）-phenylpropanol（7*）,（7S,8R）-erythro-guaiacylglycerol-β-coniferyl aldehyde ether（8）,threo-1-（4-hydroxy-3-methoxyphenyl）-1-methoxy-2-{4-[1-formyl-（E）-vinyl]-2-methoxyphenoxy}-3-propanol（9）,（7R,8R）-threo-guaiacylethoxyglycerol-β-O-4’-coniferylaldehyde ether（10）,（7R,8R）-erythro-guaiacylethoxyglycerol-β-O-4′-guaiacyl aldehyde ether（11）,（7R,8S）-erythro-guaiacylethoxyglycerol-β-O-4′-coniferyl aldehyde ether（12）,（7R,8S）-threo-guaiacylethoxyglycerol-β-O-4′-guaiacyl aldehyde ether（13）,（7R,8S）-erythro-7,8-bis（4-hydroxy-3-methoxyphenyl）-9-acetyl-7,9-propanediol（14）,p-hydroxy phenylferulate（15）,evofolin-B（16）,vladinol-D（17）,（+）-pinoresinol（18）,（7S）-3-methoxy-4-hydroxy-7-hydromethyl-phenylacetic acid-8-O-（3’-methoxy-4’-hydroxy）phenyl ester（19*）,（+）-erythro-7 ethylguaiacyl glycerol（20）,（7S,8R）-threo-3-methoxy-4-hydroxy-7-methoxy-8-O-（2’-methoxy-4’-aldehyde-phenyl）-phenylpropanol（21*）,ferulaldehyde（22）,cinnamic acid（23）,4-hydroxycinnamic acid methyl ester（24）,β-hydroxypropiovanillone（25）,dihydroconiferyl alcohol（26）,1,6-diethyl citrate（2 7）,3-hydroxy-3-carboxyethyl-1-methoxy-5-ethoxy-citric acid ester（28*）,3-hydroxy-3-carboxymethyl-1,5-diethoxy-citric acid ester（29*）,3-carboxyethyl-3-hydroxyglutaric acid 1,5-dimethyl ester（30）,1,5-diethyl citrate（31）,tris-ethyl aminocitrate（32）,1-ethoxy-6-methoxy-citrate（33）,triethyl citrate（34）,trimethyl citrate（35）,vanillic acid（36）,methyl vanillate（37）,methylgallate（38）,3,4-dihydroxybenzoic acid（39）,4-hydroxybenzaldehyde（40）,4’-hydroxy-3’-methoxy-phenol-β-D-[6-O-（4’’-hydroxy-3’’,5’’-dimethoxybenzoate）]glucopyranoside（41）,3-（8-pentadecenyl）phenol（42）,3-（（8E,11E）-pentadeca-8,11,14-pentadecatrien-1-yl）phenol（43）,pyroglutamic acid ethyl ester（44）,1,1,2-ethane tricarboxylic acid-1-hydroxy-1,1-diethyl ester（45）,mucic acid dimethyl ester（46）,5-hydroxymethylfuran-2-carbaldehyde（47）,cirsiumaldehyde（48）,β-sitosterol（49）,methyl linoleate（50）,methyl myristate（51）,2-hydroxy-butanedioic acid dimethylester（52）,palmitic acid（53）.Among the 53 compounds isolated and identified,1-26 were phenylpropanoids,27-35 were citrates,36-43 were single-ring phenolics and 50-53 were fatty acids,of which 6 new compounds（4,7,19,21,28,29）.Based on the study of chemical constituents,partial monomer compounds were tested for antioxidant,anti-inflammatory andα-glucosidase inhibitory activities in vitro.Compared with vitamin C(IC₅₀=34.69±1.70μM),compounds 7,10,16,18 and 26 have significant DPPH free radical scavenging activity.Compounds 3,4,9,22 have significant anti-inflammatory activity,and they are stronger than minocycline(IC₅₀=9.44±2.88μM).Compared with acarbose(IC₅₀=189.40±3.13μM),compound 17 has a robust inhibition ofα-glucosidase activity.This study preliminarily elucidates the anti-inflammatory,antioxidant and hypoglycemic active constituents of Chinese olive,which lays a good foundation for its clinical application and further development.