New 3',8''-linked biflavonoids from Selaginella uncinata displaying protective effect against anoxia.

Seven 3',8''-linked bioflavonoids, including one new compound, (2''S)-2'', 3''-dihydroamentoflavone-4'-methyl ether and six known compounds: (2S)-2,3- dihydroamentoflavone-4'-methyl ether, (2S,2''S)-2,3,2'',3''-tetrahydroamento- flavone-4'-methyl ether, (2S,2''S)-tetrahydroamentoflavone, (2S)-2,3-dihydro- amentoflavone and (2''S)-2'',3''-dihydroamentoflavone (6) and amentoflavone, were isolated from the 60% ethanolic extract of Selaginella uncinata (Desv.) Spring. The structures of these compounds were elucidated mainly by analysis of their 1D and 2D NMR spectroscopic data, and their absolute configurations were determined by circular-dichroism (CD) spectroscopy. All the seven compounds showed protective effect against anoxia in the anoxic PC12 cells assay, in which compound 6 displayed particularly potent activity.

Phenylpropanoid and flavonoids from osteoprotective fraction of Drynaria fortunei.

A new phenylpropanoid (1), 12-O-caffeoyl-12-hydroxyldodecanoic acid, and a new chalcone (2), 3'-lavandulyl-4-methoxyl-2,2',4',6'-tetrahydroxylchalcone, together with eight known compounds including one chalcone (3), five flavanones (4-8) and two flavonols (9, 10), have been isolated from one of the osteoprotective fractions of Drynaria fortunei (Kunze) J. Sm., which is used as a folk medicine for the treatment of osteoporosis. All these compounds were found for the first time from the genus Drynaria. The structures of the new compounds were elucidated on the basis of spectroscopic analysis.

[Study on absorption mechanism of puerarin and its nanoparticles across Caco-2 cell model].

OBJECTIVE: To study the absorption mechanism of puerarin and its nanoparticles across Caco-2 cell model. METHODS: The Caco-2 monolayer model was used to explore the effect of time and drug concentration on the absorption of puerarin and its nanoparticeles. The drug concentration was determined by high-performance liquid chromatography and the Papp was caculated. RESULTS: The puerarin-PLGA-NP could significantly improve the absorption of puerarin. Puerarin was not only absorbed simply through passive diffusion, but also had relations with high dispersion of nanoparticles, increase of affinity and interaction with intestinal mucous membrane. CONCLUSION: The main mechanism of puerarin and its nanoparticles across Caco-2 monolayer model is passive transference. Puerarin-NP could increase the absorption of the drug in intestinal epithlial.

Two new flavonol glycosides from Epimedium koreanum Nakai.

Two new flavonol glycosides, named icarisid B (1) and icarisid C (2), along with seven known flavonol glycosides were isolated from the bioassay-directed fractions of the aqueous extract of Epimedium koreanum Nakai. The structures of the two new compounds were established on the basis of chemical and spectroscopic methods (ESI-MS, 1D, and 2D NMR) as 5-hydroxyl-4'-methoxy-8-(gamma-hydroxyl-gamma,gamma-dimethyl)-propyl-3-O-alpha-L-rhamnopyranosyl-flavonol-7-O-beta-D-glucopyranoside (1) and 5-hydroxyl-4'-methoxy-8-(gamma-methoxy-gamma,gamma-dimethyl)-propyl-3-O-beta-D-glucopyranosyl(1 --> 3)-alpha-L-rhamnopyranosyl-flavonol-7-O-beta-D-glucopyranoside (2), respectively. All the nine compounds were tested for their effects on proliferation and alkaline phosphatase (ALP) activity using UMR106 cells. As a result, five compounds showed stimulating effects on both the proliferation and ALP activity, which suggested that they might be used as potential leading compounds to cure osteoporosis.

[Studies on chemical constituents of Eleutherine americana].

OBJECTIVE: To research the chemical constituents from Eleutherine americana. METHODS: Column chromatography with silica gel was employed to isolate and purify the constituents. Their structures were elucidated by means of MS and NMR. RESULTS: Eight constituents were obtained and identified as Isoeleutherol (1), eleutherin (2), isoeleutherin (3), beta-sitosterol(4), 8-hydroxy-3, 4-Dimethoxy-1-methyl-anthra-9, l0-quinone-2-carboxylic acid methyl ester (5), Hongconin (6), 4,8-Dihydroxy-3-Methoxy-1-methyl-anthra-9,10-quinone-2-carboxylic acid methyl ester (7), Eleutherinone (8), Kadsuric acid (9). CONCLUSION: Compound 9 is isolated from the plant for the first time.

Two new xanthones from the stems of Cratoxylum cochinchinense.

Two new xanthones, 6-hydroxy-3,7-dimethoxy-8-(3-methylbut-2-enyl)-6',6'-dimethyl-5'-hydroxy-4',5'-dihydropyrano(2',3':1,2)xanthone (1) and 6-hydroxy-3,7-dimethoxy-8-(2-oxo-3-methylbut-3-enyl)-6',6'-dimethyl-5'-hydroxy-4',5'-dihydropyrano(2',3':1,2)xanthone (2), have been isolated from the stems of Cratoxylum cochinchinense (Lour.) Blume. Their structures were established on the basis of spectroscopic analysis.

Phenylpropanoid and lignan derivatives from Antiaris toxicaria and their effects on proliferation and differentiation of an osteoblast-like cell line.

Antiarisin A and B (1 and 2), together with seventeen known compounds (3-19), were isolated from the EtOAc extract of the stem of Antiaris toxicaria Lesch. Their structures were determined on the basis of spectroscopic analyses and chemical methods. Most of the compounds were reported for the first time from the Antiaris genus and firstly studied for their proliferative and differentiative activity on osteoblast-like cells. Screening results indicated that, at the concentration of 10(-8) M, benzofuran lignans 5, 6, 11 and 13 could significantly stimulate the proliferation of UMR106 cells, while 8, 9, 11, 14, 15 and 17 could enhance ALP (alkaline phosphatase) activity.

A new phloroglucinol diglycoside derivative from Hypericum japonicum Thunb.

A new phloroglucinol diglycoside 1, together with eight known compounds, were isolated from Hypericum japonicum Thunb. The structure of the new compound 1 was determined by spectroscopic methods to be 4,6-dimethyl-5-O-[alpha-L-rhamnopyranosyl-(1-->6)-alpha-D-glucopyranosyl] multifidol. Different solvent extracts of Hypericum japonicum Thunb. were tested for in vivo antihypoxic activity using mice, with the EtOAc extract showing better activity.

Flavonoids and a new polyacetylene from Bidens parviflora Willd.

Fifteen flavonoids, 1-7 and 9-16, and a polyacetylene, 8, were isolated from the ethanol extract of the dried whole plant of Bidens parviflora Willd. by various chromatographic techniques. Their structures have been elucidated on the basis of spectroscopic analyses and chemical studies. Compound 8 is new and was identified as 3-(R),8(E)-decene-4,6-diyne-1,3,10-triol. All the flavonoid compounds were isolated for the first time from this plant species.

Coumarins from campylotropis hirtella (FRANCH.) SCHINDL. and their inhibitory activity on prostate specific antigen secreted from LNCaP cells.

Campylotropis hirtella (FRANCH.) SCHINDL. was used as a folk medicine for the treatment of benign prostate hyperplasia (BPH) in China. In this study, two new coumarins, 7,2',4'-trihydroxy-5-methoxy-3-arylcoumarin (1), 6-[(1S,2S)-2-angeloyloxy-1,3-dihydroxy-3-methylbutyl]-7-methoxycoumarin, named angelol M (2), together with eleven known related compounds (3-13) were isolated from this plant under the bioassay guided fractionation. All the compounds showed activity with different levels in inhibiting prostate specific antigen (PSA) secreted from androgen dependent prostate cancer cell line, LNCaP cells, using ELISA method.

Lignans isolated from Campylotropis hirtella (Franch.) Schindl. decreased prostate specific antigen and androgen receptor expression in LNCaP cells.

Accumulating epidemiological data suggest that Asian men have lower incidences of prostate cancer and benign prostate hyperplasia (BPH) compared with American and European populations and may have benefited from their higher intake of phytoestrogens in their diet. However, how these phytochemicals affect prostatic diseases is still unclear. In this study, we isolated six lignans from a plant, Campylotropis hirtella (Franch.) Schindl., which has been used as a folk medicine for treatment of BPH in China, through bioassay guided fractionation. They were dehydrodiconiferyl alcohol (C1), 4-[(-6-hydroxy-2,3-dihydro-1-benzofuran-3-yl)methyl]-5-methoxybenzene-1,3-diol (C2), erythro-guaiacylglycerol-beta-O-4'-coniferyl ether (C3), threo-guaiacylglycerol-beta-O-4'-coniferyl ether (C4), secoisolariciresinol (C5), and prupaside (C6), where C2 was identified as a new lignan analog. Their IC50 values for inhibition of prostate specific antigen (PSA) secretion were 19, 45, 110, 128, 137, and 186 microM, respectively, from C1 to C6 in LNCaP cells. Further study showed that C1-5 down-regulated cellular PSA expression and C1-4 also decreased androgen receptor (AR) expression in LNCaP cells. Furthermore, we investigated the proapoptotic effect of C1 on LNCaP cells. The active forms of caspase 3 associated with the specific proteolysis of poly (ADP-ribose) polymerase (PARP) were detected, and the antiapoptotic protein Bcl-2 was down-regulated after the treatment with C1. These results collectively indicated that these lignans may have chemopreventive or therapeutic actions for prostate cancer through suppressing AR signaling pathway and inducing apoptosis.

Sesquilignans and dilignans from Campylotropis hirtella (Franch.) Schindl.

A new sesquilignan, erythro-Guaiacylglycerol-beta-O-4'-(5')-methoxylariciresinol, together with six known compounds including three sesquilignans and three dilignans, have been isolated from Campylotropis hirtella (Franch.) Schindl. that was used as traditional Chinese medicine for treatment of benign prostate hyperplasia. All these known compounds were found for the first time from the family leguminosae. The structure of the new compound and its relative configurations were elucidated on the basis of detailed spectroscopic analysis (NMR and MS). These compounds showed no obvious inhibition effect on prostate specific antigen secretion in LNCaP cells by ELISA method.

Copacamphane, picrotoxane and cyclocopacamphane sesquiterpenes from Dendrobium nobile.

Dendronobilins K - N, four new sesquiterpenes with copacamphane-type (1), picrotoxane-type (2, 3) and cyclocopacamphane-type (4) skeletons, were isolated from the n-BuOH soluble fraction of the 60% ethanol extract of the stems of Dendrobium nobile. Their structures were established as 2beta,11,12-trihydroxycopacamphan-15-one (1), (2beta,3beta,4beta,5beta)-2,4,11,12-tetrahydroxypicrotoxan-3(15)-olactone (2), (2beta,3beta,5beta)-2,11,12,13-tetrahydroxypicrotoxan-3(15)-olactone (3), and (5beta,8beta)-cyclocopacamphane-5,8,12,15-tetrol (4) on the basis of spectroscopic analysis. Compounds 3 and 4 were inactive in both immunomodulatory and antioxidant bioassay in vitro.

Effects of eleven flavonoids from the osteoprotective fraction of Drynaria fortunei (KUNZE) J. SM. on osteoblastic proliferation using an osteoblast-like cell line.

Drynaria fortunei (KUNZE) J. SM. (DFE) is one of the most frequently used traditional Chinese medicines prescribed for the treatment of osteoporosis in China. The present study was designed to investigate the osteoprotective constituents from Drynaria fortunei. The 60% ethanol extract of the rhizome of D. fortunei (DFE) was chromatographed on a D-101 macroporous resin column (psi 25x150 cm); three fractions (DFA eluted with water, DFB eluted with 30% and 50% ethanol, and DFC eluted with 95% ethanol) were obtained and their osteoprotective activity as examined both in vivo and in vitro. DFB showed significant activity on both the proliferation of UMR106 cells and promoting bone mineral density (BMD) in ovariectomized (OVX) mice. A bioactivity-guided method led to the isolation of 11 flavonoids from this fraction (DFB) with antiosteoporotic activity, including two new compounds, kaempferol 3-O-beta-D-glucopyranoside-7-O-alpha-L-arabinofuranoside (1) and (R)-5,7,3',5'-tetrahydroxy-flavanone 7-O-neohesperidoside (2), along with nine known ones: three flavanones (3-5), one flavone (7), one flavonol (6), two chromones (8, 10), maltol glucoside (9), and (-)-epicatechin (11). Compounds 4-11 are reported for the first time from this genus. We investigated the proliferative effects of the 11 compounds in the UMR106 osteoblastic cell line in vitro. All compounds exhibited the proliferative activity in the UMR106 cells at most of the concentrations tested. Most compounds are reported for the first time from the Drynaria genus and this was the first study of their proliferative activity in osteoblast-like cells. The main peaks in the HPLC fingerprint of the active fraction (DFB) were also identified.

[Non-saponins from Solanum nigrum L].

OBJECTIVE: Chemical constituents of the non-saponins from Solonum nigrum L. were studied. METHODS: The separation was performed on the silic gel CC, Sephadex-LH20 CC as well as preparative HPLC. The constituents were isolated and identified by spectral methods. RESULTS: Five compounds isolated from 60% ethanol extract werre identified as 6-methoy-hydroxycoumarin (I), syringaresinol-4-O-beta-D-glucopyranoside (II), pinoresinol-4-O-beta-D-glucopyranoside (III), 3, 4-dihydroxhbenzoic acid (IV), p-hydroxybenzoic acid (V), 3-methoxy-4-hydroxyienzoic acid (VI), adenosine (VII). CONCLUSION: II, III, and VII were isolated from this genus for the first time.

Bioactive bibenzyl derivatives and fluorenones from Dendrobium nobile.

Bioassay-guided fractionation of the 60% ethanol extract of the stems of Dendrobium nobile using the DPPH assay led to the isolation of two new bibenzyl derivatives, nobilin D (1) and nobilin E (2), and a new fluorenone, nobilone (3), together with seven known compounds (4-10). Their structures were determined on the basis of spectroscopic analyses. Compounds 1, 2, 4, 7, 8, and 10 exhibited significant antioxidant activity higher than or equivalent to vitamin C in the DPPH assay, and compounds 1, 3, 4, and 7-10 displayed higher antioxidant activity than vitamin C in the ORAC assay. Compounds 1, 2, and 10 also exhibited stronger inhibitory effects on NO production than resveratrol.

Anti-osteoporotic effect of Erythrina variegata L. in ovariectomized rats.

The present study was designed to investigate whether Erythrina variegata L. (EV), which belongs to the leguminous family, exerted any beneficial effects on bone in ovariectomized rats. Daily oral administration of the EV extract at 300 and 600 mg/kg for 14 weeks to rats prevented the OVX-induced increase in the serum OCN, ALP, and urinary DPD levels. Histomorphometric analysis of the proximal end of the tibia showed that the EV extract prevented the estrogen deficiency-induced decrease in trabecular thickness and trabecular area, as well as restoring the increase in trabecular separation in a dose-dependent manner. Moreover, the EV extract improved the energy absorption and stiffness of the mid-shaft of the rat femur. Thus, the present study clearly demonstrated that EV could suppress the high rate of bone turnover induced by estrogen deficiency, inhibit bone loss and improve the biomechanical properties of bone in the OVX rats.

[Determination of saponin I in extracts of Allium macrostemnon].

OBJECTIVE: To develop an HPLC method for determination of saponin I in bulb extracts of Allium macrostemon. METHOD: The extract was refluxed by methanol and then filtrated. The filtrate was concentrated and the bioactive saponin was measured by HPLC-RID. RESULT: The calibration curve was in good linearity over the range of 5-100 microg with the regression equation of Y= 9.35 x 10(4) X - 2.78 x 10(4) (r = 0.9998) and the average recovery was 101.1% (n = 5, RSD 1.6%). CONCLUSION: The method is simple, quick and reproducible and can be applied in the quality control of A. macrostemon.

Two neolignan glucosides and antihistamine release activities from Bidens parviflora WILLD.

Two new neolignan glucosides, bidenlignasides A (1) and B (2), were isolated from the whole plant of Bidens parviflora WILLD. The structures of the two new compounds 1 and 2 established to be 3-hydroxy-1-(4-hydroxy-3-methoxyphenyl)-3-[5E-(3-hydroxypropenyl)-3-methoxy-2-O-beta-D-glucosyl)phenyl] propan-1-one and 3-{3-[1,3-dihydroxy-3-(4-hydroxy-3-methoxyphenyl)propyl]-4-hydroxy-5-methoxyphenyl}-allyl-O-beta-D-glucuside, respectively, on the basis of spectral and chemical evidence. Compounds 1 and 2 were found to inhibit histamine release from peritoneal exudate mast cells induced by antigen-antibody reaction.

Selective inhibition of the growth of cancer cells by diterpenes selected with embryonic cells of Xenopus.

We used Xenopus embryo cells with a cell cycle of 20-30 min to detect inhibitory effects on cell proliferation. Inhibition of proliferation was observed when isolated embryonic cells were incubated for 16 h in a simple salt solution containing the well-known anticancer drugs 5-fluorouracil and adriamycin. In addition, three diterpene compounds isolated from the anticancer herbal medicine kansui: kansuinin B, 20-OD-ingenol Z, and 20-OD-ingenol E specifically inhibited the proliferation of isolated embryonic cells. The inhibitory compounds selected using the embryonic cells also inhibited proliferation of certain mammalian cell types.