Constituents of Peucedanum zenkeri seeds and their antimicrobial effects.

The methanol extract of Peucedanum zenkeri L. seeds showed antimicrobial activity which is concentrated in the n-hexane fraction. Bioactivity-guided chromatographic fractionation of the seeds of P. zenkeri led to the isolation and characterization of five major coumarins, umbelliprenin, imperatorin, bergapten, isopimpinellin and byakangelicin, as well as two minor coumarins, 7-methoxy coumarin and 5-hydroxy-8-methoxy psoralen. Amongst the isolated compounds only imperatorin, bergapten and isopimpinellin were found to possess anti-microbial activity.

HPLC analysis of neo-clerodane diterpenoids from Teucrium chamaedrys.

A simple, rapid analytical method for the quantitative determination of nine neo-clerodane diterpenoids was developed. The neo-clerodane diterpenoids present in the plant material and extracts were separated with an acetonitrile-water gradient at a flow rate of 1 mL per minute. The HPLC separation was performed on a Phenomenex Luna C18(2) (150 x 4.6 mm I.D., particle size 5 microm) reversed phase column with detection at 220 nm. The limit of detection was 0.24-0.90 microg/mL. The relative standard deviation (RSD) values for the determination of neo-clerodane diterpenoids in plant extracts were less than 3.20%. This is the first analytical method developed for qualitative and quantitative analysis of nine neo-clerodane diterpenoids by HPLC with PDA detection.

An improved HPLC method for quantitative determination of six triterpenes in Centella asiatica extracts and commercial products.

An improved HPLC qualitative and quantitative method of six triterpenes (asiaticoside, madecassoside, asiatic acid, madecassic acid, terminolic acid, and asiaticoside-B) in Centella asiatica (raw plant material and preparations) is described in this paper. After 50 minutes the six active triterpenes were separated and detected in the methanolic extract at a limit of 0.01 microg/ml. The method uses a Phenomenex Aqua 5mu C18 (200 A) column as the stationary phase, a gradient mobile phase of water (0.1% TFA), acetonitrile (0.1% TFA), and methyl tert-butyl ether (0.1% TFA), and UV detection at 206 nm. The correlation coefficients for the calibration curves and the recovery rates ranged from 0.995 to 0.999 and from 98.39% to 100.02%, respectively. The qualitative and quantitative results are discussed.

Biologically active steroidal glycosides from Tribulus terrestris.

The steroidal saponin constituents obtained from Tribulus terrestris were tested for their antimicrobial and cytotoxic effects. The spirostanol-based steroidal saponins 1-3 exhibited remarkable activity against fungal organisms (Candida albicans and Cryptococcus neoformans) and cancer cell lines [human malignant melanoma (SK-MEL), human oral epidermoid carcinoma (KB), human breast ductal carcinoma (BT-549), and human ovary carcinoma (SK-OV-3)], while none of the compounds possessing the furostanol framework 4-7 showed activity. The most active spirostanol glycoside, compound 3 exhibited a broad range of anticancer activity against cell lines, SK-MEL, KB, BT-549 and SK-OV-3 at IC50s of 6.0, 7.0, 6.0 and 8.2 micrograms/ml, respectively, while compounds 1 and 2 showed selective cytotoxicity against SK-MEL at 6.7 and 9.1 micrograms/ml, respectively. The minimum inhibitory concentrations (MIC) in antifungal bioassay for compounds 1-3 varied from 1.5 to 6.2 micrograms/ml, which prompted to conclude certain structural features are required for these bioactivities.

Determination of steroidal saponins in Tribulus terrestris by reversed-phase high-performance liquid chromatography and evaporative light scattering detection.

This paper describes the first analytical method suitable for the determination of steroidal saponins in Tribulus terrestris. A separation by high performance liquid chromatography (HPLC) was achieved by using a reversed-phase (RP-18) column, evaporative light scattering (ELS) detection, and a water/acetonitrile gradient as the mobile phase. The marker compound, protodioscin, was detected at a concentration as low as 10.0 microg/mL. Several different samples of plant material were successfully analyzed, and depending on origin and plant part used for extraction, significant differences in the composition of the saponins were observed. The analysis of market products showed considerable variations of 0.17 to 6.49% in the protodioscin content.

Trojanosides I-K: new cycloartane-type glycosides from the aerial parts of Astragalus trojanus.

Three new cycloartane-type triterpene glycosides have been isolated from the aerial parts of Astragalus trojanus. The structures were established mainly by a combination of one- and two-dimensional NMR techniques [1H-1H-correlation spectroscopy (COSY), 1H-13C-heteronuclear multiple quantum correlation spectroscopy (HMQC), and 1H-13C-heteronuclear multiple-bond correlation spectroscopy (HMBC)] and high resolution electrospray ionization mass spectrometry (HR-ESI-MS) as 3-O-beta-(2',3'-di-O-acetyl)-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-16-O- acetoxy-20(R),24(S)-epoxycycloartane-3beta,6alpha,16beta,25-tetrol, 3-0-[alpha-L-rhamnopyranosyl-(1-->2)-beta-(3',4'-di-O-acetyl)-D-xylopyranosyll-6-O-beta-D-xylopyranosyl-20(R),24(S)-epoxycycloartane-3p,6alpha,16beta,25-tetrol, 3-O-beta-D-xylopyranosyl-6,16-di-O-beta-D-glucopyranosyl-20(R)24(S)-epoxycycloartane-3beta,6alpha,16beta,25-tetrol.

A new dammarane-type triterpene glycoside from Polyscias fulva.

A new dammarane-type triterpene glycoside, polysciasoside A (1), and three known compounds have been isolated from the leaves of Polyscias fulva. The structure of the new compound was established as 12-oxo-3beta,16beta,20(S)-trihydroxydammar-24-ene-3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranoside.

A new bisabolene derivative from the essential oil of Prangos uechtritzii fruits.

The fruits of endemic Prangos uechtritzii Boiss. & Hausskn. (Umbelliferae) were subjected to hydrodistillation and microdistillation. The resulting volatiles were investigated by GC-MS to determine the composition of the essential oils. 109 compounds representing 86.7% and thirty-two compounds representing 90.0% were identified and isolated by two different techniques, respectively. Column chromatography of the essential oil yielded a new bisabolene ether (7-epi-1,2-dehydrosesquicineole), which was characterized by spectral methods (GC-FTIR, 1D-, 2D NMR and HRESIMS).

Macrophyllosaponin E: a novel compound from the roots of Astragalus. oleifolius.

Macrophyllosaponin E, a novel cycloartane-type triterpene, has been isolated from the roots of Astragalus oleifolius. The structure elucidation of the compound was achieved by a combination of one- and two-dimensional NMR techniques [1H-1H-correlation spectroscopy (COSY), 1H-13C-heteronuclear multiple guantum correlation spectroscopy (HMQC), and 1H-13C-heteronuclear multiple-bond correlation spectroscopy (HMBC)l and high resolution electrospray ionization Fourier transformation mass spectrometry (HR-ESI-FT-MS).

Immunostimulatory effects of cycloartane-type triterpene glycosides from astragalus species.

In the course of our research on the oligoglycosidic constituents of Turkish Astragalus species, we have isolated a number of cycloartane-type triterpene glycosides. The current study examines the immunostimulatory effects of nineteen of these cycloartane-type compounds using a transcription-based bioassay for Nuclear Factor kappa B (NF-kappaB) activation in a human macrophage/monocyte cell line, THP-1. All compounds were inactive at 100 microg/ml except astragaloside I which increased NF-kappaB directed luciferase expression to levels about 65% as compared with maximal stimulation by E. coli lipopolysaccharide (LPS) at 10 microg/ml. None of the compounds were active at low dosage levels (0.1 microg/ml) in combination with 50 ng/ml LPS. Astragaloside I also increased mRNA expression of the inflammatory cytokines interleukin-1beta (IL-1beta) and tumor necrosis factor-alpha (TNF-alpha) as measured using reverse transcriptase-polymerase chain reaction (RT)-PCR. Based on these results it is clear that certain structural features are required for immunostimulation of cycloartane-type triterpene glycosides.

Triterpene saponins from the fruits of Hedera helix.

Six triterpene saponins, including two new compounds, were isolated from the fruits of Hedera helix L. (Araliaceae). The structures of the new compounds, named helixosides A and B, were established as 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl hederagenin 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, and 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl oleanolic acid 28-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester, respectively, on the basis of chemical and spectral data.

Cimiracemoside a: A new cyclolanostanol xyloside from the rhizome of Cimicifuga racemosa.

A new 9,19-cyclolanostane-type triterpene xyloside (1), from the rhizomes of Cimicifuga racemosa, has been isolated together with four known saponins; cimiaceroside A, 25-O-methylcimigenol-3-O-beta-D-xylopyranoside, 27-deoxyactein and 23-O-acetylshengmanol-3-O-beta-D-xylopyranoside. The structure of the new compound was established as 16beta,23:22beta,25-diepoxy-12-acetoxy-3beta,23,24b eta-trihydroxy-9,19-cyclolanost-7-ene-3-O-beta-D-xylopyranoside . For the structure elucidation, 1D- and 2D-NMR experiments and high resolution electrospray ionization Fourier transformation mass spectrometry (HRESIFTMS) were used.

A new flavonol glycoside from the aerial parts of Astragalus vulneraria.

A new flavonol glycoside, isorhamnetin 3-O-beta-D-apiofuranosyl-(1-->2)-alpha-L-rhamnopyranosyl-(1-->6)]-beta-D-galactopyranoside, and the known diglycoside, isorhamnetin 3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-galactopyranoside were isolated from the aerial parts of Astragalus vulneraria. Characterization of the two compounds was done by spectroscopic methods (1D and 2D NMR, and FAB-MS).

New steroidal glycosides from the fruits of Tribulus terrestris.

Three new steroidal saponins (1-3) were isolated from the fruits of Tribulus terrestris. Their structures were assigned by spectroscopic methods (IR, HRESIMS, 1D- and 2D-NMR) as 26-O-beta-D-glucopyranosyl-(25S)-5beta-furost-20(22)-en-3bet a, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[alpha-L-rhamnopyranosyl- (1-->4)]-beta-D-glucopyranoside (1), 26-O-beta-D-glucopyranosyl-(25S)-5beta-furost-20(22)-en-3bet a, 26-diol-3-O-alpha-L-rhamnopyranosyl-(1-->2)-[beta-D-glucopyranosyl-(1 -->4)]-beta-D-galactopyranoside (2), and 25(S)-5beta-spirostan-3beta-ol-3-O-alpha-L-rhamnopyranosyl-( 1-->2)-[b eta-D-glucopyranosyl-(1-->4)]-beta-D-galactopyranoside (3). Compound 3 showed cytotoxicity against a human malignant melanoma cell line (SK-MEL).

Two oleanene glycosides from the aerial parts of Caltha polypetala.

Two new oleanene glycosides (1-2) possessing hederagenin as the aglycone were isolated from the methanolic extract of the aerial parts of Caltha polypetala together with four known glycosides. The saccharide portion linked to C-3 of the aglycone is made up of alpha-L-arabinopyranose, alpha-L-rhamnopyranose and galactopyranose in the new compounds; while compound 1 possesses linked to C-28 a trisaccharide moiety made up of two beta-D-glucopyranose and one alpha-L-rhamnopyranose unit, in compound 2 the 28-COOH group is free. The structures were elucidated by 1D and 2D NMR experiments including 1H-1H (DQF-COSY, 1D-TOCSY, 2D-ROESY) and 1H-13C (HSQC, HMBC) spectroscopy.

Secondary metabolites from the roots of Astragalus trojanus.

Six novel cycloartane-type glycosides were isolated from the roots of Astragalus trojanus. Two of these, compounds 1 and 2, have (20R, 24S)-epoxy-3beta,6alpha,16beta,25-tetrahydroxycycloartane as the aglycon, while compounds 3-6 possess 3beta,6alpha,16beta,(24S), 25-pentahydroxycycloartane as the aglycon. The saccharide moieties linked to the C-3, C-6, and C-24 or C-25 positions of the aglycons in 1-6 contained either xylopyranose, glucopyranose, rhamnopyranose, or arabinopyranose units. Structure elucidation of compounds 1-6 was accomplished through the extensive use of 1D and 2D NMR techniques. In addition, a new oleanene glycoside (7) and a new tryptophan derivative (8) were also isolated and characterized.

Cycloartane triterpene glycosides from the roots of Astragalus brachypterus and Astragalus microcephalus.

Three new cycloartane-type triterpene glycosides, brachyosides A (1), B (3), and C (2), from the roots of Astragalus brachypterus and one new glycoside, cyclocephaloside II (4), from the roots of Astragalusmicrocephalus have been isolated together with five known saponins, astragalosides I, II, and IV, cyclocanthoside E, and cycloastragenol. The structures of the new compounds were established as 3-O-[beta-D-xylopyranosyl(1-->3)-beta-D-xylopyranosyl-6-O-beta-D-gluc opyranosyl-3beta,6alpha,16beta,24(S),25-pentahydrox ycycloartane (1), 3-O-beta-D-xylopyranosyl-6-O-beta-D-glucopyranosyl-24-O-beta-D-glucop yranosyl-3beta,6alpha,16beta,24(S),25-pentahydroxyc ycloartane (2), 20(R),24(S)-epoxy-6-O-beta-D-glucopyranosyl-3beta,6alpha,16beta , 25-tetrahydroxycycloartane (3), and 20(R), 24(S)-epoxy-3-O-(4'-O-acetyl)-beta-D-xylopyranosyl-6-O-beta-D-glucopy ranosyl-3beta,6alpha,16beta,25-tetrahydroxycycloart ane (4). For the structure elucidations, 1D- and 2D-NMR experiments and FABMS were used.