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Siberian ginseng (SG) has been widely and historically consumed as a health food product for the improvement of self well-being, but whether vascular relaxation may contribute to such a therapeutic health effect has not been studied. We therefore investigated the vasorelaxant effect of the aqueous extract of the roots of SG (Eleutherococcus senticosus Maxim) using several in vitro vascular rings prepared from dog carotid artery, rat aorta and rat mesenteric artery. SG extract (0.04-0.8 mg/ml) caused concentration-dependent relaxation in dog carotid arterial rings pre-contracted with 100 microM phenylephrine (PE), and the relaxation was primarily endothelium-dependent. Treatment with 100 microM L-NOARG (a nitric oxide synthase inhibitor) either prevented or totally reverted SG-induced relaxation, suggesting that the endothelium-dependent relaxation was mediated by NO. Similar endothelium-dependent vascular relaxant responses were also obtained with rat aortic and mesenteric arterial rings, except that it occurred over a relatively higher concentration range of SG (0.5-2.0 mg/ml). When tested in the presence of 300 microM L-NAME, the vasorelaxant effect of SG was inhibited totally in rat aorta but only partially in rat mesenteric artery. The relaxation to SG that was insensitive to L-NAME in rat mesenteric arterial rings was eliminated when the rings (both proximal and distal ends) were pre-treated with a combination of 300 microM L-NAME and 15 mM KCl indicating the involvement of endothelium-derived hyperpolarizing factor (EDHF). This vasorelaxant response of the SG extract was inhibited partially by atropine (1 microM), completely by TEA (5 mM), but not by indomethacin (1 microM) or propranolol (10 microM). SG up to 2 mg/ml had no effect on KCl-induced contraction in any of the vascular rings studied. When compared with carbachol-induced (CCh) relaxation, SG resembles CCh in that the sensitivity to L-NAME inhibition is dependent on vascular size, i.e. aorta >proximal end of mesenteric artery >distal end of mesenteric artery. However, SG exhibited different potencies to relaxation while CCh showed similar potency (EC(50) of about 0.2 microM) in all three vascular segments. In conclusion, we have demonstrated that the vascular effect of SG is endothelium-dependent and mediated by NO and/or EDHF depending on the vessel size. Other vasorelaxation pathways, such as inhibition of K(+)-channels and activation of muscarinic receptors, may also be involved.

A new phenylethanoid glycoside, plantasioside, was isolated from the aerial parts of Plantago asiatica. The structure of plantasioside was deduced from chemical and spectral evidence to be 1',2'-[beta(3,4-dihydroxyphenyl)-alpha,beta-dioxoethanol]-6'-O- caffeoyl- O-beta-D-glucopyranoside. In addition, the structure of orobanchoside from P. depressa and P. camtschatica was revised to be 1',2'-[beta(3,4-dihydroxyphenyl)- alpha,beta-dioxoethanol]-4'-O-caffeoyl-O-alpha-L-rham- nopyranosyl-(1--3)-O- beta-D-glucopyranoside from beta-hydroxy-[beta(3,4-dihydroxyphenyl)-ethyl]-4'-O-caffeoyl-O-alp ha-L- rhamnopyranosyl-(1--2)-O-beta-D-glucopyranoside.

An EtOAc extract of Artemisiae Capillari Spica inhibited both bovine lens aldose reductase (bovine-LAR) and rabbit platelet aggregation. Two simple coumarins, scoparone (1) and scopoletin (2), and three flavonoids, capillarisin (21), cirsimaritin (22) and rhamnocitrin (23), were isolated from this extract. Scoparone (1) and scopoletin (2) exhibit a potent inhibitory effect on rabbit platelet aggregation induced by four types of agent, ADP, PAF, sodium arachidonate and/or collagen. Capillarisin (21) exhibits a potent inhibitory effect on bovine-LAR. In addition, thirteen simple coumarins, five coumarin glycosides and two flavonoids were tested for their inhibitory effect against bovine-LAR and rabbit platelet aggregation.

The present study was designed to get further insight into the mode of antidepressant action of an extract prepared of the leaves of Apocynum venetum L. (AV). To evaluate biochemical changes, we used a high-performance liquid chromatography system to examine the effects of short-term (2 weeks) and long-term (8 weeks) administration of imipramine (15 mg/kg po) and an AV-extract (15, 60 and 250 mg/kg) on regional levels of serotonin (5-HT), norepinephrine (NE), dopamine (DA) and their metabolites in the rat hypothalamus, striatum and hippocampus. Pronounced changes in 5-HT, NE and DA levels were detected mainly after 8 weeks of daily imipramine treatment. Similar to imipramine, AV-extract reduced NE and DA concentrations after 8 weeks, whereas it failed to affect 5-HT levels. We speculate that the decrease in NE levels after chronic AV treatment might be based partly on the subsensitivity of presynaptic alpha(2)-receptors. In addition to the determination of central monoamine concentrations, quantitative radioligand receptor-binding studies were used to examine the effects of long-term administration of imipramine and AV-extract on beta-adrenergic binding in rat frontal cortex. [125I]CYP binding to beta-adrenergic receptors was found to be decreased after 8 weeks treatment with imipramine, whereas AV-extract had no effect on beta-receptor binding.

The vasorelaxant effects of the aqueous extract prepared from the bark of the Chinese medicinal herb, Eucommia ulmoides Oliv. (also referred to as Tu-Chung or Du-Zhong), which is a common active ingredient in traditional antihypertensive herbal prescriptions in China, have recently been characterized in rat aorta and dog carotid artery. The vasorelaxant effect of eucommia bark extract on these large elastic arteries was found to be entirely endothelium-dependent and nitric oxide (NO)-mediated. Since smaller muscular arteries play a more dominant role in the change of peripheral resistance and thus the regulation of blood pressure, we have now compared the relaxant effects of eucommia bark extract using aorta and the proximal as well as the distal ends of the superior mesenteric arteries from the rat, with a specific objective to investigate whether smaller muscular arteries also elicit endothelium-dependent vascular relaxation (EDVR) in response to eucommia bark extract. We have also determined whether the EDVR, if indeed occurring in the mesenteric arteries, is mediated entirely by NO, or whether it also involves endothelium-derived hyperpolarizing factor (EDHF). We found that all three types of vessel preparations elicit EDVR in response to the eucommia bark extract concentration-dependently in a similar manner to the relaxant responses to carbachol (CCh). Although the NO synthase inhibitor L-NAME totally abolished the EDVR in aorta, it only partial abolished EDVR in mesenteric arteries isolated from each end, the distal end being more resistant to L-NAME. However, the residual L-NAME-resistant relaxation of the rat mesenteric arteries could be further inhibited by preincubation of the vessels with the combination of L-NAME and 15-20 mM KCl (KCl itself at this low concentration caused little or no contraction). Therefore, the EDVR induced by the eucommia extract and CCh in aorta is mediated entirely by NO, and that in mesenteric arteries by NO as well as EDHF, with the EDHF component (inhibited by KCl) larger in the smaller distal end of the rat mesenteric artery. Results of our study offer a plausible mechanistic basis for the vasorelaxing action of Eucommia ulmoides Oliv., which may account for its well-documented antihypertensive action.

An X-ray analysis of oraposide, previously reported as orobanchoside and isolated from Orobanche rapumgenistae confirms the originality of an unusual cyclic structure formed by an ether linkage between a glucose molecule and a 3,4-dihydroxyphenylglycol.

The five known phenylethanoid glycosides, cistanoside F, β-hydroxyacteoside, campenoside I, acteoside and orobanchoside, and a new phenylethanoid gly

A new lignan, traxillaside and nine known lignans, arctigenin, traxillagenin, trachelogenin, matairesinol, nortrachelogenin, arctiin, tracheloside, mat

Two kaempferol glycosides [kaempferol 3-O-beta-D-glucosyl(1-->2)-beta-D-galactoside 7-O-beta-D-glucoside and kaempferol 3-O-beta-D-glucosyl(1-->2)-(6"-O-acetyl)-beta-D-galactoside 7-O-beta-D-glucoside] as well as the quercetin glycoside [quercetin 3-O-beta-D-glucosyl(1-->2)-beta-D-galactoside 7-O-beta-D-glucoside] were isolated from the stems of Trigonella foenum-graecum L. (Leguminosae) along with a known kaempferol glycoside, lilyn [kaempferol 3-O-beta-D-glucosyl(1-->2)-beta-D-galactoside]. Their structures were established by analysis of chemical and spectral evidence.

The metabolism of the plant lignans matairesinol, secoisolariciresinol, pinoresinol, syringaresinol, arctigenin, 7-hydroxymatairesinol, isolariciresinol, and lariciresinol by human fecal microflora was investigated to study their properties as mammalian lignan precursors. The quantitative analyses of lignan precursors and the mammalian lignans enterolactone and enterodiol were performed by HPLC with coulometric electrode array detector. The metabolic products, including mammalian lignans, were characterized as trimethylsilyl derivatives by gas chromatography-mass spectrometry. Matairesinol, secoisolariciresinol, lariciresinol, and pinoresinol were converted to mammalian lignans only. Several metabolites were isolated and tentatively identified as for syringaresinol and arctigenin in addition to the mammalian lignans. Metabolites of 7-hydroxymatairesinol were characterized as enterolactone and 7-hydroxyenterolactone by comparison with authentic reference compounds. A metabolic scheme describing the conversion of the most abundant new mammalian lignan precursors, pinoresinol and lariciresinol, is presented.

Antitumor effect of the stem bark of Acanthopanax senticosus HARMS (ASH) from Hokkaido (Japanese name: Ezoukogi) on human stomach cancer KATO III cells was investigated. The extract of the stem bark of ASH prepared with hot water was dissolved in distilled water and used for the assay of antitumor effect on the KATO III cells. The exposure of KATO III cells to ASH led to both growth inhibition and induction of apoptosis. Morphological change showing apoptotic bodies was observed in the cells treated with ASH. The fragmentation by ASH of DNA to oligonucleosomal-sized fragments that are characteristics of apoptosis was observed to be concentration- and time-dependent. We have investigated which component in ASH is effective on the induction of apoptosis. Among chlorogenic acid, syringaresinol di-o-beta-D glucoside, syringin, and sesamin, components of the n-butanol extract prepared from ASH, sesamin suppressed the growth and induced apoptosis in the cells. These findings suggest that growth inhibition by ASH results from the apoptosis induced by sesamin, a component of ASH.

The emergence of fungal infections due to the increase in the number of immunocompromised patients has become a matter of concern. Among the available sources for treating fungal infections, natural products can play a significant role. In this article, we have tried to categorize the different sources and chemical classes of fungitoxic agents as following: (1) animal sources such as defensins and other peptides, (2) plant sources such as terpenoids, flavonoids, and coumarins, (3) fungal metabolites like fatty acids, sugar derivatives and polyenes and (4) bacterial sources such as amino acids. The potentials of coumarins, which are mainly distributed in four plant families, Umbelliferae, Rutaceae, Leguminosae and Compositae, have been uncovered in this respect. In addition to antifungal property, the other bioactivities of coumarins include: anticoagulant, antibacterial, antiparasitie, anticancer, photodynamic, edema relieving, anti-inflammatory, radical scavenging, lipolytic, antiplatelet, and anti-allergic properties. Studies in structure-antifungal activity relationships of coumarins, which is presented here, reveal the essential strucutral features for their activity. In order to have a better understanding of the mode of action of coumarins, the cellular sites and the interactions of coumarins with biological systems have been explained. Effects on the enzymes gyrase and topoisomerase, and photodynamic reaction with lipids, proteins and DNA are among the main issues discussed. In this respect, morphological changes of Candida albicans cells due to coumarins, which are studied by scanning electron microscopy (SEM), support their biochemical effects.

Two new dimeric hydrolyzable tannins named eumaculin A (1) and eusupinin A (2) have been isolated from Euphorbia maculata L. and Euphorbia supina RAFIN., and their structures elucidated. Twelve other polyphenolic compounds including five hydrolyzable tannins and five flavonol glycosides have also been isolated.

Two new phenylethanoid glycosides, ferruginoside A (3, 4-dihydroxy-β-phenylethoxy-O-β-D-glucopyranosyl-(1→6)-2-O-caffeoyl-β-D-glucopyranoside) and ferruginoside (3, 4-dihydroxy-β-phenylethoxy-O-β-D-glucopyranosyl-(1→6)-β-D-glucopyranoside) were isolated, along with the known compounds lugrandoside and trans-ferulic acid, from the aerial parts of D. ferruginea subsp. ferruginea. For structural elucidation of the isolates, chemical transformation (acetylation, methylation, alkaline hydrolysis), one and two dimensional (COSY, HMQC, HMBC, ROESY) NMR techniques and FAB-MS were used.

Overproduction of oxygen free radical is closely related to aging, cancer, inflammation, ischemia/reperfusion injury, and arteriosclerosis (Kerr et al., 1996). For protection against these free radical related diseases, many kinds of traditional Kampo medicine and traditional Chinese medicine, which are all crude drugs, have been used clinically (Otsuka, 1988). The data on their pharmacological mechanisms increased, but these data are not enough to be evaluated scientifically (Takahashi et al., 1993, Akamatsu et al., 1998). We found acteoside (ACT) and its derivatives, isolated from oriental medicine Phacellantus tubiflorus, as potent inhibitors of lipid peroxidation in mitochondria (Pan and Hori, 1994, Pan and Hori, 1996). We recently found that methyl α-D-glucoside (Me-Glc; Figure 1) enhanced the anti-peroxidative activity of acteoside in rat liver mitochondria (Sakamaki et al., 1996).

(+)-Syringaresinol di-O-s-D-glucoside, a lignan from Eleutherococcus [Siberian ginseng, Eleutherococcus senticosus (Rupr. et Maxim.) Maxim. = Acanthopanax senticosus (Rupr. et Maxim.) Harms] and Cortex eucommiae (Eucommia ulmoides Oliv.), enhanced s-endorphin levels in rat plasma, which can provide an immune-enhancing effect. Mauritianin, a flavonoid from Herba catharanthi (Catharanthus roseus (L.) G. Don = Vinca rosea L.), enhanced the 12-O-tetradecanoylphorbol-13-acetate (TPA)-suppressed delayed-type hypersensitivity reaction in mice, indicating that mauritianin may augment the resistance of the immune system to cancer. The 2,3-dihydroxybenzoic acid from periwinkle (Vinca minor L.) showed a strong radical-scavenging activity, which is associated with a lower risk of cancer. Arctigenin and trachelogenin, lignans from Caulis trachelospermi [Trachelospermum jasminoides (Lindl.) Lern.], were shown to have a high inhibitory effect on TPA-induced ear edema, which reflects an antitumor-promoting effect in two-stage carcinogenesis. Also, Caulis trachelospermi contains luteolin, which has an anticlastogenic effect on micronucleus induction in γ-ray-irradiated mice.

Publisher Summary Woody plants are capable of synthesizing a wide range of phenylpropane derivatives, including lignans, neolignans, coumarins, and flavonoids. The chapter presents a study in which the wood of A. sachalinensis was extracted with 95% EtOH. Repeated silica-gel column chromatographies of the diethyl ether solubles of the EtOH extract resulted in the isolation of fourteen lignans. Todolactol A, B, C, and D have not been reported as naturally occurring lignans, but similar types of lignans have been isolated from Carissa edulis , Piper clusii , P. cubeba , Dacrydium intermedium , Abies mariesii, and A. koreana . The family, Salicaceae, is very widely distributed in the temperate and subarctic zones of the northern hemisphere. Taxonomically, the family is usually divided into four genera, Populus , Salix , Toisusu , and Chosenia . The EtOH extracts of the wood of S. sachallnensis was fractionated with diethyl ether and the solubles subjected to silica-gel column and preparative thin-layer chromatographies to give (+)-syringaresinol and two lignan esters.

The aim of this study is to investigate the pharmacological effect of the stem bark of Acanthopanax senticosus Harms from Hokkaido (Japanese name: Ezoukogi) in place of the root bark as a restorative tonic on the stress-induced gastric ulcer. In the test, the extract of the stem bark of A. senticosus prepared with hot water was dissolved in water and used for the assay of the protective effect of gastric ulcer (erosion) on stressed rats that were restrained on cold water. The result from a single oral administration of the stem bark of A. senticosus-extract (50, 100 and 500 mg/kg, per day) dissolved in 1 ml distilled water did not show any protective effect on gastric ulcer, but the protective effect was observed in a dose-dependent manner from the oral administration of the extract (50, 100 and 500 mg/kg, per day) for 2 weeks. Pre-administration of the stem bark of A. senticosus-extract in a dose of 500 mg/kg showed the most potent inhibition without affecting either body or adrenal glands weights. Among ether, chloroform, n-butanol and aqueous residue extracts from the stem bark of A. senticosus-extract, the n-butanol extract used for oral administration for 2 weeks showed an obvious inhibition of 61.1% on gastric ulcer, compared with the control group which was treated with distilled water in the same way. Chlorogenic acid and syringaresinol di-o-beta-D-glucoside, as the major components of the n-butanol extract, showed a significantly inhibitory effect on gastric ulcer, at 21.4% and 51.3%, respectively. We suggested that the protective effect of the stem bark of A. senticosus on gastric ulcer may be partially due to those of chlorogenic acid and syringaresinol di-o-beta-D-glucoside.

The five phenylethanoids, acteoside (1), cistanoside F (2), lavandulifolioside (3), plantamajoside (4) and isoacteoside (5) were isolated from the herb of Plantago lanceolata L. (Plantaginaceae). Compounds 1, the major phenylethanoid in the herb of P. lanceolata L., and 4, the major phenylethanoid in the herb of P. asiatica L., showed inhibitory effects on arachidonic acid-induced mouse ear edema.

A new polyphenol, 1,3,5-tri- O -caffeoylquinic acid, accompanied by 3,5-di- O -caffeoylquinic acid, has been isolated from the fruit of Xanthium strumarium .

Chlorogenic acid, robinin and a flavonol triglycoside were isolated from the leaves of Vinca major . The structure of the triglycoside was determined to be kaempferol 3- O -(6″- O -rhamnopyranosyl)-galactopyranoside 7- O -glucopyranoside by fast atom bombardment, electron impact and negative ion desorption chemical ionization mass spectrometry.

Flavonoid glycosides (22 compounds) were measured by fast atom bombardment, and the positive and negative ion mass spectra were compared. The mass spectra showed clear molecular ion species. Fast atom bombardment mass spectrometry provided useful information for the structural elucidation of flavonoid glycosides.Positive ion spectra in particular were useful for flavonol 3,7-O-diglycosides, while the negative ion spectra were useful for flavonoid glycoside methyl ether.

A new lignan 1 and two phenolic compounds, scopoletin and vanillic acid, were isolated from the stems of Trachelospermum asiaticum NAKAI var. intermedium NAKAI (Apocynaceae). The structure of 1 was elucidated as (2R, 3R) 2-4"-hydroxy-3"-methoxybenzyl-3-3', 4', 5'-trimethoxybenzylbutyrolactone by analysis of the carbon-13 nuclear magnetic resonance, mass and circular dichroism spectra.

The technique of positive- and negative-ion fast atom bombardment mass spectrometry has been shown to be capable of producing molecular mass and useful fragmentation information for the structural elucidation of chlorogenic acids. The mass spectra of chlorogenic acid and the related compounds 3′- O -methylchlorogenic acid, neochlorogenic acid, 4,5-dicaffeoyl quinic acid and 1,5-dicaffeoyl quinic acid are compared with those obtained by electron impact mass spectrometry.

Attempts were made to introduce an alcoholic hydroxyl group stereospecifically at the C-5 or C-6 position of 2, 3-dibenzylbutyrolactone lignans with lead tetraacetate and osmic acid as oxidizing agents. 5-Acetoxyarctigenin monoacetate (III) was obtained from arctigenin monoacetate (II), 5-acetoxyisoarctigenin monoacetate (XIII) from isoarctigenin monoacetate (XII) and 5-acetoxytrachelogenin diacetate (XXIII) from trachelogenin diacetate (XXII) by oxidation with lead tetraacetate in acetic acid. 6-Hydroxyisomethyltrachelogenin (XXXII) was obtained from 3-(3, 4-dimethoxybenzyl)-2-(3, 4-dimethoxybenzylidene) butyrolactone (XXXI) by oxidation with osmic acid. The 13C-NMR spectra of these oxidation products and analogs are discussed with regard to the differences of the chemical shifts resulting from changes in the substituents and the stereochemistry of the 2, 3-dibenzylbutyrolactone skeleton.

In addition to a known caffeoyl glycoside of 3, 4-dihydroxyphenethyl alcohol, acteoside (1), a new caffeoyl glycoside of β, 3, 4-trihydroxyphenethyl alcohol, designated as β-hydroxyacteoside (2), was isolated from the fruits of Forsythia viridissima LINDLEY (Oleaceae). The structure of 2 was established as β, 3, 4-trihydroxyphenethyl-O-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside on the basis of analysis of the carbon-13 nuclear magnetic resonance spectrum and chemical evidence.

Two biologically active coumarins, scopoletin (1) and isofraxidin (2), along with known coumarins, esculetin (3), fraxetin (4), esculin (5) and fraxin (6), were newly isolated from the bark of Fraxinus japonica BLUME (Oleaceae). On the other hand, the bark of F. mandshurica RUPR. var. japonica MAXIM gave only known coumarins, fraxetin (4), fraxinol (7) and mandshurin (8).

Two new flavonol triglycosides, named manghaslin (I) and clitorin (II), were isolated from the leaves of Cerbera manghas L. (Apocynaceae). The structures of I and II were elucidated as quercetin-3-O-L-rhamnosyl-(1→2)-O-[L-rhamnosyl-(1→6)] D-glucoside (I) and kaempferol-3-O-L-rhamnosyl-(1→2)-O-[L-rhamnosyl-(1→6)] D-glucoside (II), respectively, by chemical and gas chromatography-mass spectrometric studies.