Studies On The Chemical Constituents And Bioactivities Of Mallotus Apelta & Potentilla Anserine

The chemical constituents and bioactivities of two traditional Chinese medicines, Mallotus apelta(Lour.)Muell.-Arg,and Potentilla anserine L.,were studied in this paper.Mallotus apelta(Lour.)Muell.-Arg.(Euphorbiaceae) is widely distributed in the south of China.Its roots and leaves are used in traditional Chinese medicine for the treatment of chronic hepatitis,ulcer,eczema and hemostasis.In our ongoing searching for hepatoprotective compounds from natural sources using rat hepatic epithetlial stem-like cells(WB-F344) with D-galactosamine as a screening system,the 70% ethanolic extract of the roots of M.apelta showed significant hepatoprotective activity. The petroleum ether soluble fraction of 70%ethanolic extract also showed moderate cytotoxic activity.In order to elucidate the bioactive components of M.apelta,we carried out the chemical investigation of the roots of M.apelta.By using various separation technologies,24 compounds were isolated.On the basis of spectroscopic and chemical methods,their structures were established as follows:malloapelin A(M1),malloapelin B(M2),malloapelin C(M3),5'-demethylaquillochin(M4),cleomiscosins A(M5), cleomiscosins B(M6),malloapelin D(M7),dearabinosyl pneumonathoside(M8), scopoletin(M9),quercetin(M10),schizandriside(M11),vanillic acid glucoside(M12), berchemolide(M13),1-O-β-D-glucopyranosyl-(2S,3R,4E,SZ)-2-[(2-hydroxyhexadecanoyl)amido]-4, 8-octadecadiene-1,3-diol(M14),1-O-β-D-glucopyranosyl-(2S,3R,4E, 8E)-2-[(2-hydroxyoctadcaenoyl)amido]-4,8-octadecadiene-1,3-diol(M15),β-amyrin acetate(M16),erythrodiol(M17),1up-20(29)-en-3β,30-diol(M18),2α-hydroxyaleuritolic acid 3-p-hydroxybenzoate(M19),α-amyrin acetate(M20),aleuritolic acid (M21),β-sitosterol(M22),daucosterol(M23),stigmasterol(M24).Among them,there were three new coumarinolignoids(malloapelin A～C,M1～M3) and a new sesquiterpenoid(malloapelin D,M7).Thirteen known compounds(M5,M8,M10～M19,M21) were isolated for the first time from this species.We proposed a plausible biosynthetic pathway for M1.It arise by oxidative coupling processes between 6,7,8-trihydroxy-coumarin and 3-methoxy-caffeyl alcohol.The hepatoprotective activities of three new compounds M1-M3 were assessed by measuring their effects on the cell survival rate.All the coumarinolignoids showed inhibitory activity against D-galactosamine-induced toxicity in WB-F344 cell at 10^-4M in vitro,without any obvious cytotoxic effects with inhibitory rates of 3.5,11.3 and 26.2%,respectively.The antitumor test in vitro against human tumor cell lines with MTT method indicated that M2 showed cytotoxic activity against BGC-823 with an IC₅₀ value of 0.74μM,and M3 showed cytotoxic activity against A549 and A2780 with IC₅₀ value of 0.65 and 0.43μM,respectively.However,in the anti-HIV test in vitro,no compounds showed obvious activities against HIV.Potentilla anserine L.(Rosaceae) has long been used as traditional Chinese medicinal herbs for anti-rheumatism,detoxification,and curing diabetes,which distributed in the north and southwest of China.In our previous biological investigations,the ethanol extracts,petroleum ether and EtOAc soluble fractions showed PTP1B andα-glucosidase inhibitory activities.By means of chromatography methods and spectral technologies,we carried out the chemical investigation of P.anserine.53 Compounds were isolated.On the basis of spectroscopic and chemical methods,their structures were established as follows: potentilin(P1),2,6-dimethyl-2,3-dihydro-4-oxo-4H-pyran-2-acetic acid(P2),kaempferol-3-O-β-D-(6-O-trans-p-coumaroyl)glucop yranoside(P3), kaempferol-3-O-β-D-(2-O-trans-p-coumaroyl)glucopyranoside(P4), apigenin-6-C-(2"-O-α-L-rhamnopyranosyl-β-D-glucopyranoside)(P5), vicenin-â…¡(P6),apigenin-6-C-β-D-glucopyranosyl-8-C-β-D-xylopyranoside(P7), schaftoside(P8),isovitexin(P9),rutin(P10),quercetin-3,7-di-O-β-D-glucopyranoside(P11), isoscutellarein-8-O-β-D-glucopyranoside(P12),luteolin-3'-O-β-D-glucopyranoside(P13), luteolin-7-O-β-D-glucuronide(P14),luteolin-7-O-β-D-glucopyranoside(P15), quercetin-7-O-β-D-glucopyranoside(P16),astragalin(P17), reynoutrin(P18),quercetin-3-O-β-D-glucuronide(P19),isoquercitrin(P20),quercetin-3-O-α-L-rhamnopyranoside(P21), luteolin(P22),quercetin(P23),5,7-dihydroxychromone(P24), loliolide(P25),isololiolide(P26),dehydrocomifoliol(P27),ellagic acid 4-O-β-D-glucopyranoside(P28),ellagic acid 4-O-β-D-xylopyranoside(P29),3'-O- methylellagic acid 4-O-β-D-glucopyranoside(P30),brevifolincarboxylic acid(P31), brevifolin(P32),vanillic acid 4-O-β-D-glucopyranoside(P33),picein(P34),4-glucosyloxybenzoic acid(P35),3,4-dihydroxybenzoic acid(P36),caffeic acid(P37),E-4-hydroxycinnamic acid(P38),4-hydroxybenzoic acid(P39),ethyl-3,4-dihydroxybenzoate (P40),4-hydroxy-3,5-dimethoxy benzoic acid(P41),β-hydroxypropiovanillone(P42), 4-hydroxybenzaldehyde(P43),4-hydroxyacetophenone(P44),chlorogenic acid(P45), crytochlorogenic acid(P46),neochlorogenic acid(P47),ursolic acid(P48),β-sitosterol (P49),daucosterol(P50),5-hydroxymethyl furaldehyde(P51),E-2-butenedioic acid (P52),ethyl hydrogen succinate(P53).Among them,P1 was a rare new diflavonol ester ofμ-truxinic acid and P2 was a new normonoterpenoid.42 Compounds(P4～P7, P9～P13,P15～P16,P18～P19,P21～P22,P24～47,P51～P53) were isolated for the first time from this species.By using HPLC-DAD and LC-MS,we got the fingerprints of the methanol extracts of P.anserine.Some peaks of fingerprints were identified by comparing with the 53 compounds isolated from P.anserine.The PTP 1B inhibitory activities of eighteen compounds isolated from P.anserine. were evaluated.At a concentration of 10μM,P3,P4,P10,P11,P29 and P48 showed moderate PTP1B inhibitory activities with inhibitory rates of 51.0,51.7,30.4,45.9, 64.1 and 34.4%,respectively.The petroleum ether,EtOAc and aqueous soluble fractions showed anti-flammatory activities against croton oil-induced rat ear swell at a dose of 100mg/kg,with inhibitory rates of 21.8,44.9 and 66.4%,respectively.In the anticancer activities assay,the EtOAc soluble fractions showed nonselective cytotoxicty against HCT-8,Bel-7402,BGC-823,A549 and A2780,with IC₅₀ values of 2.34,26.93,7.54,13.06 and 25.88μg/mL,respectively.The petroleum ether soluble fractions showed selective cytotoxicty against Bel-7402 and BGC-823 with IC₅₀ values of 19.89 and 17.78μg/mL,respectively.Compound P48 also showed selective cytotoxicty against A549 and A2780 with IC₅₀ values of 0.76×10^-6 and 0.73×10^-6 M, respectively.