Terpene Glycosides Research Articles

Investigation of biologically active natural products using online LC-bioassay, LC-NMR, and LC-MS techniques

Biologically active natural products were isolated and identified by means of online LC‐bioassay, LC‐NMR, and LC‐MS from Cussonia barteri (Araliaceae), Terminalia macroptera (Combretaceae), Jasminum subtriplinerve (Oleaceae), and Petunia hybrida (Solanaceae). From C. barteri we obtained the novel C18‐polyacetylene (+)‐9(Z),17‐octadecadiene‐12,14‐diyn‐1,11(S),16(S)‐triol (2) along with its acetate 3, and two new quinic acid esters, 1′‐O‐chlorogenoylchlorogenic acid (4) and 1′‐O‐chlorogenoylneochlorogenic acid (5). Chromatographic work up of T. macroptera extracts yielded a new hydrolyzable tannin, isoterchebulin (6), and 4,6‐O‐isoterchebuloyl‐D‐glucose (7) along with some gallic acid derivatives. From J. subtriplinerve six terpene glycosides 13–18 related to anatolioside A (12), and from P. hybrida seven highly molluscicidal sucrose esters 19–22b were isolated.

Cytotoxic terpenoid and immunosuppressive phenolic glycosides from the root bark of Dictamnus dasycarpus.

Five new compounds, two degraded terpene glycosides, dasycarpusides A and B (1, 2), and three phenolic glycosides, 2-methoxy-4-hydroxymethylphenol 1-O-alpha-rhamnopyranosyl-(1"-->6')- beta-glucopyranoside ( 3), 2-methoxy-4-acetylphenol 1-O-alpha-rhamnopyranosyl-(1"-->6')-beta-glucopyranoside (4), and 2-methoxy-4-(8-hydroxyethyl)-phenol 1-O-alpha-rhamnopyranosyl-(1"-->6')-beta-glucopyranoside (5), were isolated from the water-soluble constituents of the root bark of Dictamnus dasycarpus Turcz.(Rutaceae). Their structures were elucidated by spectroscopic analysis and chemical evidence. Moreover, it was found that dasycarpuside A (1) showed weak cytotoxic activity against A-549 (human lung adenocarcinoma) cell line, while 4 and 5 showed more remarkable activity of inhibiting the proliferation of T-cells in vitro.

The role of non-Saccharomyces species in releasing glycosidic bound fraction of grape aroma components--a preliminary study.

The purpose of the study was to evaluate the effect of beta-glycosidase activity in wine yeasts in releasing terpene glycosides from grape juice. Glycosidase activity was screened in 160 yeasts by testing their ability to hydrolyse arbutine on agar plates. Only non-Saccharomyces species exhibited beta-glycosidase activity. Enzyme activity, based on hydrolytic activity on p-nitrophenyl-beta-glycoside, was mainly located in the whole cell fraction, with smaller amounts in permeabilized cells being released into the growth medium. The hydrolysis of glycosides was determined by HRGC-MS, confirming the role of yeast in the liberation of monoterpenols, especially linalool and geraniol. The results indicate the potential of microbial beta-glycosidases for releasing flavour compounds from glycosidically-bound, non-volatile precursors, with significant implications for wines made from less aromatic grapes. This study confirms the role of non-Saccharomyces species in enhancing wine aroma and flavour, suggesting that the future lies with controlled use of mixed cultures in winemaking.

Prunioside A: a new terpene glycoside from Spiraea prunifolia.

Prunioside A (1) has been isolated from an EtOAc-soluble extract of Spiraea prunifolia var. simpliciflora by a combination of chromatographic techniques. The structure was determined primarily by extensive NMR experiments. Compound 1 is a unique terpene glycoside. Its acetylated derivative (1a) inhibited nitric oxide production in murine macrophage-like RAW 264.7 cells in a dose-dependent manner.

Characterization of ginseng saponins using electrospray mass spectrometry and collision-induced dissociation experiments of metal-attachment ions.

Electrospray mass spectrometry (ESMS) and collision-induced dissociation (CID) methodologies have been developed for the structural characterization of ginseng saponins (ginsenosides). Ginsenosides are terpene glycosides containing a triterpene core to which one to four sugars may be attached. They are neutral molecules which readily form molecular metal-attachment ions in positive ion ESMS experiments. In the presence of ammonium hydroxide intense deprotonated ions are generated. Both positive and negative ion ESMS experiments were found to be useful for molecular mass and structure determination of ten ginsenoside standards. Negative ion experiments made possible the determination of the molecular mass of each ginsenoside standard, the mass of the triterpene core and the masses and sequences of the sugar residues. Positive ion ESMS experiments with the alkali metal cations Li+ or Na+ and the transition metal cations Co2+, Ni2+ and Zn2+ were also useful in determining molecular masses. These alkali and transition metal cations form strongly bonded attachment ions with the ginsenosides. As a result, the CID mass spectra of the metal attachment ions show a variety of (structure characteristic) fragmentations. These experiments can be used to determine the identity of the triterpene core, the types and attachment points of sugars to the core and the nature of the O-glycosidic linkages in the appended disaccharides. Combining the results from the negative and positive ion experiments provides a promising approach to the structure analysis of this class of natural products.

Triterpene glycosides defend the Caribbean reef sponge Erylus formosus from predatory fishes

The reef sponge Erylus formosus (Demospongiae: Geodiidae) from the Bahamas and southern Florida contains a suite of triterpene glycosides that, at a natural volumetric concentration, deters predation by the fish Thalassoma bifasciatum in laboratory assays, and a natural assemblage of reef fishes in field assays. Antifeedant metabolites were isolated by bioassay-guided fractionation of extracts of E. formosus using standard chromatographic methods and identified by nuclear mag- netic resonance (NMR) spectroscopy and mass spectrometry. Included in the deterrent mixture from E. formosus collected in the Bahamas and Florida were at least 6 related triterpene glycosides pos- sessing identical aglycones but with different sugar residues. Two additional compounds with a penasterol triterpene core (formoside, and an N-acetyl galactosamine derivative, formoside B) were found in specimens from the Bahamas but not Florida. Formoside, while being the major deterrent metabolite of E. formosus from the Bahamas, is less potent than the other triterpene glycosides on a weight per volume basis. As a mixture, the triterpene glycosides protect E. formosus from predatory reef fishes, but when these compounds were separated into fractions some failed to deter feeding at natural concentrations. As compounds of this type are beginning to be recognized as prevalent sponge metabolites, we suggest that terpene glycosides may have important ecological functions, just as a defensive role has been ascribed to similar compounds in sea stars, sea cucumbers, and ter- restrial plants.

Flavonoid and terpene glycosides from European Ebenus species

Flavonoid and terpene glycosides from European Ebenus species

Description of theβ-glucosidase activity of wine yeasts

β-glucosidase activity of differentSaccharomycesstrains has been detected on the basis of its hydrolytic activity onpara-nitrophenyl-β-glucoside (pNPG) and terpene glycosides of Muscat wine. This enzymatic activity is induced by the presence of boundβ-glucose as the only carbon source in the medium and seems to be a characteristic of the yeast strain.β-glucosidase is associated with the cell wall and is found in the insoluble fraction obtained from lysed yeast cells.Saccharomyces β-glucosidase is quite glucose independent, so that its activity is reduced by about 40% in the presence of 200 g/l of glucose, but it is inhibited by about 50% with 5% ethanol in the medium; therefore, its technological use seems to be restricted to the first stages in the wine-making process.

The effect of a long‐term water stress on the metabolism and emission of terpenes of the foliage of Cupressus sempervirens

ABSTRACTThe effects of long‐term water stress on water and terpene contents of the foliage of Cupressus sempervirens were studied. A great deal of water was lost over 2 months before a remarkable stabilization. A strong decrease of all the classes of terpenes accompanied this dehydration. Mono‐ and sesquiterpene hydrocarbons and free terpenols were almost entirely metabolized, whereas esters and terpene glycosides rose slightly and remained at a constant level when the water content had stabilized. Although a significant part of the mono‐ and sesquiterpene hydrocarbons was emitted in the early stage of stress application, the major part was used by the plant in response to the drought conditions.

Liquid chromatographic—thermospray mass spectrometric analysis of crude plant extracts containing phenolic and terpene glycosides

In crude plant extracts, constituents of biological or pharmaceutical interest often exist in the form of glycosides. Mass spectral investigations of these metabolises require soft ionization techniques such as desorption chemical ionization (D/CI) or fast atom bombardment if information on molecular mass or sugar sequence is desired. Thermospray (TSP) provides mass spectra similar to those obtained with positive-ion D/CI-MS using NH 3 and thus is potentially applicable to on-line analyses for these compounds and can be applied to plant extract analysis. Extracts of Gentianaceae species (containing secoiridoids and xanthone mono- and diglycosides), Polygalaceae (containing flavonol di- and triglycosides), Pedaliaceae (containing iridoids, phenylpropanoid glycosides) and Leguminosae (containing triterpene glycosides) have been screened by LC-TSP-MS. Ale plant extracts were analysed under standard LC-TSP-MS conditions on reversed-phase columns using methanol—water or acetonitrile—water gradients. Good optimization of the temperature of the source and the vaporizer was crucial for the observation of pseudo-molecular ions of glycosides.

Thermospray LC-MS Analysis of Phenolic and Terpene Glycosides in Crude Plant Extracts

Thermospray LC-MS Analysis of Phenolic and Terpene Glycosides in Crude Plant Extracts

The Chemical Composition of Terpene Alcohols and Phenols from the Essential Oil and Terpene Glycosides Isolated fromThymus pulegioidesGrowing Wild in Dalmatia

The Chemical Composition of Terpene Alcohols and Phenols from the Essential Oil and Terpene Glycosides Isolated from<i>Thymus pulegioides</i>Growing Wild in Dalmatia

Triterpene glycosides of the leaves of Digitalis ciliata

Two new terpene glycosides have been isolated from the leaves of the foxgloveDigitalis ciliata Trautv.: β-D-glucopyranosyl oleanolate 3-O-[O-β-D-xylopyranosyl-(1 → 4)-α-L-rhamnopyranoside] and oleanolic acid 3-O-[O-β-D-xylopyranosyl-(1 → 4)-α-L-rhamnopyranoside].

Contribution of Terpene Glycosides to Bitterness in Muscat Wines

Terpene glycosides were isolated from a bitter Muscat of Alexandria wine. When the glycosidic extract was added to a model system or to wine at levels one and two times the concentration in the original wine, no significant difference in taste was produced, whereas in water at single-strength concentration, a significant difference was produced (p

EVOLUTION AND SPECIATION OF HOST PLANT SPECIFIC YEASTS.

SUMMARY In summary, three stages in the for- mation of species are discernible in cactus inhabiting yeasts. Pichia heedii may rep- resent the initial stage in host race for- mation and exhibits a single gene change accompanying the shift of host plants within the same subtribe. Pichia ame- thionina could represent the final stage of host race formation and the beginning of the speciation stage. This species shows changes at two independent loci when it shifts between two related subtribes of cactus, and exhibits postmating break- down for hybrids of the host varieties. The varieties differ by their resistance to tri- terpene glycosides found in one subtribe of columnar cacti. This difference is shown to be controlled by a single tem- perature sensitive gene and this genetic difference may be singularly responsible for the divergence of the two varieties. The two varieties of Pichia opuntiae may illustrate the final stage of the speciation process. This species shows considerable metabolic change when it shifts between hosts of different cactus tribes and dem- onstrates prezygotic barriers to gene ex- change.

Studies on terpene glycosides. II. Gas chromatographic optical resolution of dl-menthol and dl-borneol via its acetyl glucoside derivatives.

Studies on terpene glycosides. II. Gas chromatographic optical resolution of dl-menthol and dl-borneol via its acetyl glucoside derivatives.

Studies on terpene glycosides. I. Synthesis and properties of menthyl glycosides.

With an aim of developing menthol derivatives having good solubility in water, the glycosidation reaction of menthols was extensively investigated, such as the condensation of menthols with acetobromoglucose by the method of Koenig-Knorr and that with fully acetylated sugars in the presence of acidic catalysts. The water-solubility of menthyl monosaccharides was generally poor, but that of menthyl disaccharides was good enough for practical usage as food additives and medicines. Furthermore, these glycosides derivatives were advantageously utilized for optical resolution of dl-menthol because of their high crystallinity.

Isolement et structure du cantleyoside : Nouveau glucoside terpénique de Cantleya corniculata (Becc.) Howard, (Icacinacées).

From the trunk bark of Cantleya corniculata (Becc.) Howard (Icacinaceae), a new terpene glycoside has been isolated to which the name cantleyocide and structure I have been attributed.