Two new maltol glycosides and cyanogenic glycosides from <Emphasis Type="Italic">Elsholtzia rugulosa</Emphasis> Hemsl.

Two new maltol glycosides, maltol 6′-O-β-d-apiofuranosyl-β-d-glucopyranoside and maltol 6′-O-(5-O-p-coumaroyl)-β-d-apiofuranosyl-β-d-glucopyranoside, were isolated from Elsholtzia rugulosa Hemsl. along with 11 known compounds including prunasin and amygdalin. The structures were determined on the basis of spectroscopic and chemical evidence. This is the second example of isolation of cyanogenic glycosides from Lamiaceous plants.     

Two new phenolic glycosides from <Emphasis Type="Italic">Syringa reticulata</Emphasis>

Two new phenolic glycosides—3′-O-β-d-glucopyranosysalidroside (1) and cis-echinacoside (2)—together with four known ones—forsythoside B (3), decaffeoylacteoside (4), osmanthuside F (5) and (−)-olivil-4′-O-β-d-glucopyranoside (6)—were isolated from the leaves of Syringa reticulata. Their structures were established on the basis of spectral and chemical data.     

Lignan glycosides from the leaves of <Emphasis Type="Italic">Osmanthus heterophyllus</Emphasis>

Seven known lignan glycosides were isolated from the leaves of Osmanthus heterophyllus: (+)-syringaresinol 4-O-β-d-glucopyranoside, (+)-syringaresinol 4, 4′-O-di-β-d-glucopyranoside, (+)-medioresinol 4, 4′-O-di-β-d-glucopyranoside, (+)-medioresinol 4-O-β-d-glucopyranoside, (+)-pinoresinol 4, 4′-O-β-d-glucopyranoside, (+)-epipinoresinol 4-O-β-d-glucopyranoside and phillyrin. Their structures were determined on the basis of spectral data.     

Lignan and flavonoid glycosides from <Emphasis Type="Italic">Urtica laetevirens</Emphasis> Maxim.

A new compound named pinoresinol 4-O-α-l-rhamnopyranosyl (1 → 2)-β-d-glucopyranoside (1) together with six known compounds, isolariciresinol 9-O-β-D-glucopyranoside (2), apigenin 6,8-di-C-β-d-glucopyranoside (3), luteolin 7-O-neohesperidoside (4), luteolin 7-O-β-d-glucopyranoside (5), 5-methoxyluteolin 7-O-β-d-glucopyranoside (6), and rutin (7), were isolated from the aerial parts of Urtica laetevirens Maxim. All of the above compounds were isolated from this plant for the first time.     

Inhibitory effect of<Emphasis Type="Italic">Trans-N-p</Emphasis>-coumaroyl tryamine from the twigs of<Emphasis Type="Italic">Celtis chinensis</Emphasis> on the acetylcholinesterase

The methanolic extract of the twigs of Celtis chinensis was found to show inhibitory activity on acetylcholinesterase (AChE), an enzyme that plays a role in the metabolic hydrolysis of ACh. Bioassay-guided fractionation of the methanolic extract resulted in the isolation of N-p-coumaroyl tyramine, as an inhibitor on AChE. This compound inhibited AChE activity in a dose-dependent manner, and the IC50 value of trans-N-p-coumaroyl tyramine was 34.5 microg/mL (122 microM).     

Flavonol glycosides from the aerial parts of<Emphasis Type="Italic">Aceriphyllum rossii</Emphasis> and their antioxidant activities

The methanol extract obtained from the aerial parts ofAceriphyllum rossii (Saxifragaceae) was fractionated into ethyl acetate (EtOAc),n-BuOH and H₂O layers through solvent fractionation. Repeated silica gel column chromatography of EtOAc andn-BuOH layers afforded six flavonol glycosides. They were identified as kaempferol 3-O-β-D-glucopyranoside (astragalin,1), quercetin 3-O-β-D-glucopyranoside (isoquercitrin,2), kaempferol 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (3), quercetin 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyrano-side (rutin,4), kaempferol 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (5) and quercetin 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (6) on the basis of several spectral data. The antioxidant activity of the six compounds was investigated using two free radicals such as the ABTS free radical and superoxide anion radical. Compound1 exhibited the highest antioxidant activity in the ABTS2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging method. 100 mg/L of compound1 was equivalent to 72.1±1.4 mg/L of vitamin C, and those of compounds3 and5 were equivalent to 62.7±0.5 mg/L and 54.3±1.3 mg/L of vitamin C, respectively. And in the superoxide anion radical scavenging method, compound5 exhibited the highest activity with an IC₅₀ value of 17.6 ± 0.3 μM. In addition, some physical and spectral data of the flavonoids were confirmed.     

Two new neolignan glycosides from leaves of <Emphasis Type="Italic">Osmanthus heterophyllus</Emphasis>

Two new neolignan glycosides, (7R, 8R)-threo-guaiacylglycerol-8-O-4′-sinapyl ether 7-O-β-d-glucopyranoside (1) and (7S, 8R)-5-methoxydehydrodiconiferyl alcohol 4-O-β-d-glucopyranoside (2), and four known ones (3–6), were isolated from the leaves of Osmanthus heterophyllus. The structures of compounds 1–6 were established on the basis of spectral and chemical data.     

Cytotoxic coumarins from the root of<Emphasis Type="Italic">Angelica dahurica</Emphasis>

Ten coumarins were isolated from the root of Angelica dahurica by repeated silica gel column chromatography. Their chemical structures were elucidated on the basic of physicochemical and spectroscopic data. Among them, oxypeucedanin hydrate acetonide (7) was isolated for the first time from this plant. Cytotoxicity of coumarins isolated were determined in vitro against L1210, HL-60, K562, and B16F10 tumor cell lines by MTT method. Pangelin (5) and oxypeucedanin hydrate acetonide (7) showed a potent cytotoxic activity with the IC50 values of 8.6 to 14.6 microg/mL against four kinds of tumor cell lines. Other compounds showed the moderate cytotoxic activity or no activity against the tumor cell lines.     

Antioxidant flavone glycosides from the leaves of<Emphasis Type="Italic">Sasa borealis</Emphasis>

Sasa borealis (Poaceae) is a perennial medicinal plant which is a major source of bamboo leaves in Korea. Then-BuOH extract ofS. borealis leaves exhibited significant antioxidant activity against the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and a cytoprotective effect against oxidative damage in HepG2 cells. Bioactivity-guided fractionation by column chromatography led to the isolation of two antioxidative flavonoid C-glycoside derivatives, isoorientin (2) and isoorientin 2”-O-α-i_-rhamnoside (4) along with tricin 7-0-β-D-glucopyranoside (1) and apigenin 6-C-β-D-xylopyranosyl-8-C-β-D-glucopyranoside (3). Their structures were identified on the basis of chemical and spectroscopic methods. The radical scavenging activity and cytoprotective effect against oxidative damage of all the isolated compounds were also evaluated. Isoorientin (2) and isoorientin 2-O-α-L-rhamnoside (4) showed potent free radical scavenging activity with 1C₅₀ values of 9.5 and 34.5 μM, respectively, and strong cytoprotective effects againstt-BOOH-induced oxidative damage in HepG2 cells, at very low concentrations of 1.1 μM isoorientin and 0.8 μM isoorientin 2-O-α-L-rhamnoside. This is the first report of the isolation and antioxidant activity of compounds 2 and 4 from S.borealis.     

Two new phenylpropanoid glycosides from the stem bark of<Emphasis Type="Italic">Acanthopanax trifoliatus</Emphasis>

Two new phenylpropanoid glycosides, 1-beta-D-glucopyranosyl-2,6-dimethoxy-4-propenylphenol (1) and 1-[beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl]-2,6-dimethoxy-4-propenylphenol (2) were isolated from the stem bark of Acanthopanax trifoliatus along with four known compounds (3-6). Their structures were established on the basis of spectral and chemical evidences.     

Resin glycosides from the leaves and stems of <Emphasis Type="Italic">Ipomoea digitata</Emphasis>

Alkaline hydrolysis of the ether-soluble resin glycoside (jalapin) fraction of the leaves and stems of Ipomoea digitata L. (Convolvulaceae) gave six organic acids, isobutyric, (S)-2-methylbutyric, tiglic, n-decanoic, n-dodecanoic, and cinnamic acids, and two glycosidic acids, quamoclinic acid A and operculinic acid A. Further, a new genuine resin glycoside, named digitatajalapin I, was isolated from the jalapin fraction, along with three known resin glycosides. Their structures have been determined on the basis of chemical and spectroscopic data.     

Norisoprenoids and hepatoprotective flavone glycosides from the aerial parts of<Emphasis Type="Italic">Beta vulgaris</Emphasis> var.<Emphasis Type="Italic">cicla</Emphasis>

(+)-Dehydrovomifoliol (1), 3-hydroxy-5alpha,6alpha-epoxy-beta-ionone (2), vitexin 7-O-beta-D-glucopyranoside (3), and vitexin 2'-O-beta-D-glucopyranoside (4) were isolated as new constituents from the aerial parts of Beta vulgaris var. cicla. Compounds 3 and 4 demonstrated hepatoprotective activity with values of 65.8 and 56.1%, respectively, in primary cultured rat hepatocytes with CCl4-induced cell toxicity, compared to controls. This was comparable to that of silibinin (69.8 %) which was used as a positive control.     

Hypocholesterolemic property of<Emphasis Type="Italic">Yucca schidigera</Emphasis> and<Emphasis Type="Italic">Quillaja saponaria</Emphasis> extracts in human body

This study was undertaken to observe the effects of the blend of partially purified Yucca schidigera and Quillaja saponaria extracts on cholesterol levels in the human's blood and gastrointestinal functions, and to determine if a new cholesterol-lowering drug can be developed by the further purification of the extracts. Ultrafiltration and sequential diafiltration increased the amounts of steroidal saponin in aqueous yucca extract and terpenoid saponin in aqueous quillaja extract from 9.3% and 21.4% to 17.2% and 61.8%, respectively. Taking 0.9 mg of the blend (6:4, v:v) of the resulting filtrates a day for 4 weeks resulted in the decreases in total and LDL cholesterol levels in blood plasma of hyper-cholesterolemic patients with enhancement in gastrointestinal symptoms of patients.     

A new sesquiterpene from <Emphasis Type="Italic">Artemisia vulgaris</Emphasis>

The dichloromethane extract of the air-dried leaves of Artemisia vulgaris afforded a new sesquiterpene 1, caryophyllene oxide, phytyl fatty acid esters, squalene, stigmasterol and sitosterol. The structure of 1 was elucidated by extensive one- and two-dimensional nuclear magnetic resonance spectroscopy.     

Assessment of the antibacterial activity of phenylethanoid glycosides from <Emphasis Type="Italic">Phlomis lanceolata</Emphasis> against multiple-drug-resistant strains of <Emphasis Type="Italic">Staphylococcus aureus</Emphasis>

Three phenylethanoid glycosides, forsythoside B (1), phlinoside C (2) and verbascoside (3), were isolated from the methanol extract of the leaves of Phlomis lanceolata, an Iranian medicinal plant, by reversed-phase preparative high-performance liquid chromatography (HPLC), and the structures of these compounds were elucidated conclusively by ultraviolet (UV), mass spectrometry (MS) and a series of 1D and 2D nuclear magnetic resonance (NMR) analyses. The antibacterial properties of 1–3 against five multi-drug-resistant (MDR) strains of Staphylococcus aureus have been assessed by the rapid and robust microtitre-plate-based serial dilution method. While compounds 1 and 3 showed considerable activities against all five strains, compound 2 was inactive at the test concentrations.     

A new phenolic glycoside syringate from the bark of <Emphasis Type="Italic">Juglans mandshurica</Emphasis> MAXIM. var. <Emphasis Type="Italic">sieboldiana</Emphasis> MAKINO

A new phenolic glycoside syringate, 4′-hydroxy-2′,6′-dimethoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (1), together with two known ones, 2′-hydroxy-4′-methoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (2) and 4′-hydroxy-2′-methoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (3), were isolated from the bark of Juglans mandshurica MAXIM. var. sieboldiana MAKINO. Their structures were established on the basis of spectral and chemical data.     

A benzenoid from the stem of<Emphasis Type="Italic">Acanthopanax senticosus</Emphasis>

Seven compounds were isolated from the stem of Acanthopanax senticosus by repeated column chromatography. Their structures were elucidated as isovanillin (1), (-)-sesamin (2), isofraxidin (3), (+)-syringaresinol (4), 5-hydroxymethylfurfural (5), eleutheroside B (6), and eleutheroside E (7) by spectral analysis. Among them, isovanillin (1) was isolated for the first time from the family Araliaceae.     

A new kaempferol 7-<Emphasis Type="Italic">O</Emphasis>-triglucoside from the leaves of<Emphasis Type="Italic">Brassica juncea</Emphasis> L

From the leaves of Brassica juncea, a new rare kaempferol 7-O-triglucoside isolated and characterized as kaempferol 7-O-beta-D-glucopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->6)]-glucopyranoside (1) based on the spectroscopic evidences. This compound was found to be a scavenger of 1,1-diphenyl-2-picrylhydrazyl radical.     

Platelet anti-aggregatory effects of coumarins from the roots of<Emphasis Type="Italic">Angelica genuflexa</Emphasis> and<Emphasis Type="Italic">A. gigas</Emphasis>

Five coumarins, isoimperatorin (1), pabulenol (2), isooxypeucedanin (3), oxypeucedanin hydrate (4) and osthol (5) were isolated from the MeOH extract of Angelica genuflexa in the course of searching for anti-platelet and anti-coagulant components from plants. Pabulenol (2) was isolated from A. genuflexa for the first time. The five compounds isolated from A. genuflexa, together with decursinol angelate (6), decursin (7) and nodakenin (8) from A. gigas were evaluated for their effects on platelet aggregation and blood coagulation. Compounds 2, 5, 6 and 7 were observed to be either equally effective or 2-4 times more inhibitory than ASA in both arachidonic acid and U46619 (TXA2 mimetic) induced platelet aggregations.     

Anti-Inflammation activity of<Emphasis Type="Italic">Actinidia polygama</Emphasis>

The fruit of Actinidia polygama (AP) has long been used as a folk medicine in Korea for treating pain, rheumatic arthritis and inflammation. The present investigation was carried out to determine the in vivo and in vitro anti-inflammatory activity of AP using several animal models of inflammation. The 70% ethanol extract of the fruit of AP significantly inhibited acetic acid-induced, vascular permeability in a dose dependent manner (23%, 38%, and 41% inhibition at doses of 200 mg/kg, 500 mg/kg and 1000 mg/kg, respectively). This effect was maintained in AP water-soluble fraction (APW). The APW fraction also showed significant inhibitory activity against the rat paw edema induced by a single treatment of carrageenan. In vitro experiments were performed to demonstrate the inhibitory activities of APW (100 microg/ml) on lipopolysaccharide (LPS)-induced nitric oxide (NO) and prostaglandin E2 (PGE2) production. The results showed that APW dose-dependently suppressed LPS-induced NO production in RAW 264.7 macrophages without a notable cytotoxic effect and also decreased inducible NO synthase (iNOS) protein expression. APW also showed a significant inhibitory effect in LPS-induced PGE2 production and cyclooxygenase-2 (COX-2) expression.