Study On The Chemical Constituents From The Fruits Of Embelia Ribes Burm.f.and Their Bioactivities

Embelia ribes Burm f.is a woody shrub belonging to the genus of Embelia(Myrsinaceae).In this study,the bioassay-guided isolation strategy was used to separate the constituents of butyrylcholinesterase inhibitors from the fruits of E.ribes.The results showed that the 70%EtOH extract of the fruits of E.ribes exhibited the inhibitory activity of butyrylcholinesterase,and the 95%EtOH elute of D101 macroporous adsorption resin column chromatography was the active fraction.In our investigation on the chemical constituents of the active fraction(ER-E).58 compounds were isolated through various chromatographic techniques,such as silica gel column chromatography,ODS column chromatography,Sephadex LH-20 column chromatography and reversed-phase high performance liquid chromatography.Based on the comprehensive analysis of spectroscopic data(MS,UV,IR,NMR),physical chemical properties and modified Mosher method,all the isolated compounds were elucidated.Their structures were identified as(5Z,8Z)-1,16bis(3,5-dihydroxyphenyl)-hexadeca-5,8-diene-1,16-dione(1*),(R)-1,14-bis(3,5-dihydroxyphenyl)14-hydroxy-tetradecan-1-one(2*),(1R,14R)-1,14-dihydroxy-1,14-bis(3,5-dihydroxyphenyl)tetradecanol(3*),(1R,16R)-1,16-dihydroxy-1,16-bis(3,5-dihydroxyphenyl)-hexadecanol(4*),(Z)1,16-bis(3,5-dihydroxyphenyl)hexadec-8-ene-1,16-dione(5*),(1R,16R,Z)-1,16-dihydroxy-1.16bis(3.5-dihydroxyphenyl)-hexadec-8-ene-1,16-diol(6*),(5Z,8Z)-1,16-bis(3,5-dihdroxyphenyl)hexadeca-5.8-diene-1-one(7*),(1R,5Z,8Z,16R)-1,16-dihydroxy-1,16-bis(3,5-dihydro xyphenyl)hexadeca-5,8-diene-1,16-diol(8*),1-(3,5-dihydroxy-2,6-dimethoxyphenyl)tridecan-2-one(9*),(R)3,5-dihydroxyphenyl-1’-hendecanol(10*),virenol A(11),1-(3,5-Dihydroxyphenyl)heptan-1’-one(12),1-(3,5-dihydroxyphenyl)nonan-1-one(13),1-(3,5-dihydroxyphenyl)undecan-l-one(14),1(3,5-dihydroxyphenyl)tridecan-1-one(15),pentaketide(16),5-heptylresorcinol(17),5-nnonylresorcinol(18),5-n-undecylresorcinol(19),5-n-tridecylresorcinol(20),β-DGlucopyranoside,2,4-dihydroxy,6-methyl,1-(9"Z,12"Z)-9",12"-octadecadienoate(21*),β-DGlucopyranoside,2,4-dihydroxy,6-methyl,1-(8"Z,11"Z,14"Z)-8",11",14"-octadecatraenoate(22*),βD-Glucopyranoside,2,4-dihydroxy,6-methyl,1-hexadecanoate(23*),1,2-di-β-D-Glucopyranoside,4hydroxy-6-methylphenyl(24*).benzeneacetic acid,4,hydroxy-2-β-D-glucopyranoside-6-[(4’hydroxy-3’,5’-dimethoxybenzoyl)oxy]-methyl ester(25*),vaccihein A(26),myrsinoside A(27),myrsinoside B(28),orcinol glucoside(29),methyl-4-hydroxy-3,5-dimethoxybenzoate(30),methyl 2-O-β-D-glucopyranosyl-2,4,6-trihydroxybenzoate(31),2,6-dimethoxy-4-hydroxyphenol-1-O-β-Dglucopyranoside(32),myricitrin-5-methyl ether-3-O-(3"-O-acetyl)-α-L-rhamnoside(33*),myricitrin-5-methyl ether-3-O-(4"-O-acetyl)-α-L-rhamnoside(34*).quercetin-5-methyl ether-3-O(4"-O-acetyl)-α-L-rhamnoside(35*),isorhamnetin-3-O-rutinoside(36),cacticin(37),myricetin 3rhamnoside(38),quercetin 3-glucoside(39),mearnsetin 3-(2",4"-diacetylrhamnoside)(40),myricetin 3-(3",4"-O-diacetylrhamnoside)(41),quercetin 3-O-(4"-O-acetyl)-α-L-rhamnoside(42),syringetin 3-O-β-D-glucoside(43),myricetin 3-O-(3"-O-acetyl)-α-L-rhamnoside(44),myricetin 3O-(4"-O-acetyl)-α-L-rhamnoside(45),myricitrin-5-methyl ether(46),quercitrin 3-O-α-Lrhamnoside(47),3’,5’-di-C-β-glucopyranosylphloretin(48),laricetrin 3-β-glucoside(49),sakurasosaponin(50),(3β,16α,20β)-3,16,28,29-quahydroxyolean-12-en-3-{O-β-D-glucopyranosyl-(1→2)O-[β-D-glucopyranosyl-(1→4)]-α-L-arabinopyranoside}(51*),davuricoside H(52),(8R*,13R*)11,11-dimethyloctahydro-1H-3a,6,1-(epipropane[1,1,3]triyl)azulen-1-ol(53*),(-)-caryophllene βoxide(54),cloven-2β,9α-diol(55),5-O-methylembelin(56),embelin(57),roseoside(58).Among them.20 compounds(1-10.21-25,33-35,51.53)are new compounds,33 compounds(11.14-20.26-31,36-46,48-50,52,54-56,58)were reported from the Embelia genus for the first time.Noticeably,compounds 1-8 which possessed double aromatic rings linking with an aliphatic chain,are reported from the genus of Embelia for the first time to the best of our knowledge.44 of the isolated compounds(1-4.6,8,10-14,16-23,25-30,33-36,38-39,41,44-52.55-57)were tested for the inhibitory activity of butyrylcholinesterase and acetylcholinesterase.The results showed that compound 57(embelin)exhibited potent inhibitory activity of butyrylcholinesterase and acetylcholinesterase.Especially,compound 57 showed inhibitory effect equivalent to the positive butyrylcholinesterase inhibitor iso-OMPA.Compound 8 displayed moderate inhibitory activity of butyrylcholinesterase and acetylcholinesterase.In addition,12 alkylresorcinols(1-4,6,8,10-14,16)were evaluated for their cytotoxic activity against A549,Hep 3B and HCC1806 human cancer cell lines.Compounds 4,6 and 8 exhibited moderate cytotoxicity against three cancer cell lines.