Research On The Chemical Constituents Of Gynostemma Pentaphyllum (Thunb.) Makino

Gynostemma pentaphyllum (Thunb.) Makino (Cucurbitaceae) is a herbal medicine with anticancer activity, widely distributed in China, Korea and Japan. It is famous as "Southen Ginseng". The biological active constituents are dammarane-type glycosides, called gypenosides, which are structurally correlated to the ginseng saponins. Pharmacological investigation demonstrated that extracts of this plant exhibited a variety of biological effects, such as anticancer, anti-inflammatory and cadiovascular effects. In our serious of studies on the anticancer natural medicines, we have found some active compounds. As a continuation of our work for discovering more effective components, we have now investigated G. pentaphyllum (Thunb.) Makino, which is the first example of ginsenosides (Rb1, Rb3, Rd, etc.) ever found from a plant not belonging to the Araliaceae. Based on the review on the chemical constituents and pharmacological research of G. pentaphyllum, the chemical constituents were studied and their antitumor activities were tested.By means of many different chromatographic methods such as silica gel, Sephadex LH-20, reversed phase ODS column and P-HPLC chromatography, 38 compounds were isolated from the 75% ethanol extract of the herbs of Gynostemma pentaphyllum. On the basis of spectroscopic analysis (UV, IR, NMR, MS) and physicochemical characters, they were identified as (23S)-21R-O-n-butyl-3β,20ξ,21-trihydroxy-21,23-epoxydammar-24-ene 3-O-[a-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside (1), (23S)-21S-O-n-butyl-3β,20ξ,21 -trihydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rhamnopyranosyl-(1→2)][β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside (2), (23S)-21R-O-n-butyl-19-oxo-3β,20ξ,21 -trihydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rharnnopyranosyl(1→2)] [β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (3), (23S)-21S-O-n-butyl-19-oxo-3β,20ξ,21 -trihydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rhamnopyranosyl(1→2)] [β-D-xylopyran-osyl(1→3)]-α-L-arabinopyranoside (4), (23S-21R-O-n-butyl-3β,20ξ,21 -trihydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rhamnopyranosyl(1→2)] [β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (5), (20S)-3β,20,21-trihydroxydammar-24-ene 3-O-[α-L-rhamnopyranosyl-(1→2)][β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside (6), gylongiposideⅠ(7),α-spinaster-ol (8),β-sitosterol (9),α-spinasterol 3-Oβ-β-D-glucopyranoside (10), daucosterol (11), gypenosideⅢ(ginsenoside Rb1, 12), gypenosideⅣ(ginsenoside Rb3, 13), gypenosideⅧ(ginsenoside Rd, 14), gypenosideⅪⅤ(15), gypenosideⅫ(ginsenoside F2,16), gypenosideⅩⅢ(17), rutin (18), malonic acid (19), (20R,23R)-3β,20-dihydroxydammar-24-en-21-oic acid 21,23-lactone 3-0-[α-L-rhamnopyranosyl(1→2)] [β-D-xylopyranosyl(1→3)]-6-O- acetyl-β-D-glucopyranoside (20), (20S,23S)-3β,20-dihydroxydammar-24-en-21-oic acid 21,23-lactone 3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-6-O-acetyl-β-D-glucopyranoside (21), gypenoside XLIX (22), (20S)-3β,20,21-trihydroxydarnmar-24-ene 3-O- {[α-L-rhamnopyranosyl(1→2)] [β-D-xylopyranosyl(1→3)]-β-D-glucopyranosyl}-21 -O-β-D-glucopyranoside (23), (23S,23S)-19-oxo-3β,20ξ,21,26-tetrahydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (24), (23R,23R)-19-oxo-3β,20ξ,21,26-tetrahydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (25), (20R,23R)-19-oxo-3β,20-dihydroxydammar-24-en-21-oci acid 21,23-lactone 3-O-[α-L-rhamnopyranosyl-(1→2)][β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (26), (20S,23S)-19-oxo-3β,20-dihydroxydammar-24-en-21-oci acid 21,23-lactone 3-O-[α-L-rhamnopyranosyl(1→2)] [β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (27), (205)-3β,20,21-trihydroxydam-mar-23,25-diene 3-0-{[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)] -β-D-glucopyranosyl}-21-O-β-D)-glucopyranoside (28), (205)-19-oxo-3β,20,21 -trihydroxydam-mar-23,25-diene 3-O-{[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-a-L-arabinopyranosyl}-21-O-β-D-glucopyranoside (29), (23S)-21R-O-ethyl-19-oxo-3β,20ξ,21-trihydroxy-21,23-epoxydammar-24-ene 3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyran-osyl(1→3)]-α-L-arabinopyranoside (30), (235)-19-oxo-3β,20ξ,21ξ-trihydroxy-21,23-epoxyda-mmar-24-ene 3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(13)]-α-L-arabino-pyranoside (31), (20S)-19-oxo-3β,20,21ξ,25-tetrahydroxy-21,24ξ-cyclodammarane 3-0-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (32), (20R)-19-oxo-3β,20,21ξ,23ξ-tetrahydroxy-21,24ξ-cyclodammar-24-ene 3-O-[α-L-rham-nopyranosyl(1→2)][β-D-xylopyranosyl(1→3)]-α-L-arabinopyranoside (33), (20R,23R)-3β, 20-dihydroxydammar-24-en-21-oic acid 21,23-lactone 3-O-[α-L-rhamnopyranosyl(1→2)] [β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside (34), (205,235)-3β,20-dihydroxydammar-24-en-21-oic acid 21,23-lactone 3-O-[α-L-rhamnopyranosyl(1→2)][β-D-xylopyranosyl-(1→3)]-β-D-glucopyranoside (35), (205,235)-3β,20-dihydroxydammar-24-en-21-oic acid 21,23-lactone 3-O-[β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside (36), (20R,23R)-3β,20-dihydroxydammar-24-en-21-oic acid 21,23-lactone 3-O-[β-D-xylopyranosyl(1→3)]-β-D-glucopyranoside (37), quercetin (38). Among them, compounds 1-6, 24-29, 36 and 37 were determined as new compounds by chemical and spectroscopic methods.In the course of our search for triterpene saponins with antitumor activity, by MTT methods, the in vitro cytotoxicity activities against cancer cell lines of some compounds isolated were assayed. The effects of compounds on human cancer cells growth, expressed as the IC50 value, for HL-60 cells lines compounds 1-5,26,33,36-37 showed growth inhibitory effects and differentiation induction abilities, compound 3 was the most potent with the IC50 value of 8.45μmol/L. For Colon 205 and Du 145 cell lines 1-5, and 7 showed growth inhibitory effects and differentiation induction abilities, compound 2 showed strong against Colon 205 cell lines with IC50 value of 22.95μmol/L, and compound 3 showed strong against Du 145 cell lines with IC50 value of 17.41μmol/L. For A2780 and OVCAR-3 cells lines compounds 20,21,34 and 35 showed growth inhibitory effects and differentiation induction abilities, compound 20 showed moderate antitumor activities against A2780 and OVCAR-3 cell lines with IC50 value of 10.40μmol/L and 2.8μmol/L, respectively.