Showing papers on "Triterpene published in 2006"
TL;DR: In this paper, a new OSC gene (named as PNA) was expressed in a lanosterol synthase deficient (erg7) Saccharomyces cerevisiae strain GIL77.
183 citations
TL;DR: Fractionation of leaf extracts of Ugni molinae Turcz showed that some extracts have potent anti-inflammatory activities, and all three triterpene acids inhibited TPA-induced inflammation with potencies comparable to that of indomethacin.
147 citations
TL;DR: A nano-HPLC electrospray ionization multi-stage tandem mass spectrometry approach was applied to a complex crude triterpene saponin extract of Chenopodium quinoa seed coats, suitable for quality control and screening of extracts designated for pharmaceutical, agricultural, and industrial applications.
137 citations
TL;DR: 3-O-glycosides of lupane-type triterpenoids represent an interesting class of potent in vitro cytotoxic agents and show that cancer cell lines are 8- to 12-fold more sensitive to the 3- O-alpha-L-rhamnopyranoside derivative of betulinic acid than the healthy cells.
131 citations
TL;DR: The results suggest that while methyl jasmonate may be used as an inducer of enzymes involved in the triterpenoid synthesis downstream from 2,3-oxidosqualene in both C. asiatica and G. glauca, in the case of R. aculeatus it inhibited the enzyme involved in sterol synthesis upstream from cycloartenol.
116 citations
TL;DR: Six new triterpene saponins, theasaponin A(2) (2) showed an inhibitory effect on ethanol-induced gastric mucosal lesions in rats at a dose of 5.0 mg/kg, p.o., and its activity was more potent than that of omeplazole.
Abstract: Six new triterpene saponins, theasaponins A1 (1), A2 (2), A3 (3), F1 (4), F2 (5), and F3 (6), were isolated from the saponin fraction of the seeds of Camellia sinensis. The stereostructures of 1−6 were elucidated on the basis of chemical and physicochemical evidence. Theasaponin A2 (2) showed an inhibitory effect on ethanol-induced gastric mucosal lesions in rats at a dose of 5.0 mg/kg, p.o., and its activity was more potent than that of omeplazole. Structure−activity relationships for theasaponins on ethanol-induced gastroprotective activities may be suggested as follows: (1) the 28-acetyl moiety enhances activity; (2) theasaponins having a 23-aldehyde group exhibit more potent activities than those with a 23-hydroxymethyl group or a 23-methoxycarbonyl group.
110 citations
TL;DR: The results demonstrated the total content and quantity of each of the main bioactive compounds were strongly dependent on the extraction solvents and locations, indicating that the quality control of the bioactive ingredients in the leaves of D. kaki, derived extracts and phytomedicines is critical to ensure its clinical benefits.
105 citations
TL;DR: Sessiloside and chiisanoside inhibited pancreatic lipase activity in vitro, and addition of the saponin-rich fraction to a high-fat diet suppressed the body weight gain of mice.
Abstract: Three known saponins, chiisanoside, 11-deoxyisochiisanoside, and isochiisanoside, and one novel saponin, 3,4-seco-4(23),20(29)-lupadiene-3,28-dioic acid 28-O-alpha-l-rhamnopyranosyl (1-->4)-beta-d-glucopyranosyl (1-->6)-beta-d-glucopyranoside, referred to as sessiloside, were isolated from a hot water extract of Acanthopanax sessiliflorus leaves. All of these saponins were lupane-type triterpene triglycosides, and their concentrations were 4.1, 1.0, 0.5, and 0.4% (w/w) of the total extract, respectively. Sessiloside and chiisanoside inhibited pancreatic lipase activity in vitro, and addition of the saponin-rich fraction to a high-fat diet suppressed the body weight gain of mice. The possibility of application of the lupane-type saponins from A. sessiliflorus leaves to the treatment of obesity is discussed.
100 citations
TL;DR: One new and eight known ceanothane- and lupane-type triterpenes were isolated from the root bark of Ziziphus cambodiana PIERRE (Rhamnaceae) and the structure of the new compound was elucidated as 3-O-(4-hydroxy-3-methoxybenzoyl)ceanothic acid (3-O-vanillylceanothi acid) (1).
Abstract: One new and eight known ceanothane- and lupane-type triterpenes were isolated from the root bark of Ziziphus cambodiana PIERRE (Rhamnaceae). Based on spectral analyses, the structure of the new compound was elucidated as 3-O-(4-hydroxy-3-methoxybenzoyl)ceanothic acid (3-O-vanillylceanothic acid) (1), while the known compounds were identified as lupeol (2), betulinaldehyde (3), betulinic acid (4), 2-O-E-p-coumaroyl alphitolic acid (5), alphitolic acid (6), zizyberanalic acid (7), zizyberenalic acid (8) and ceanothic acid (9). Compounds 1, 5 and 8 exhibited significant in vitro antiplasmodial activity against the parasite Plasmodium falciparum, with inhibitory concentration (IC50) values of 3.7, 0.9 and 3.0 μg/ml, respectively. Compounds 1 and 3—8 showed antimycobacterial activity against Mycobacterium tuberculosis with respective MIC values of 25, 25, 25, 12.5, 50, 50 and 100 μg/ml.
93 citations
TL;DR: Experimental data support the notion from a previous clinical study that TE from the outer bark of birch might represent a new tool for the topical treatment of skin cancer and skin cancer precursors like actinic keratoses.
Abstract: Triterpenes are biologically active secondary plant substances that display antimicrobial, hepatoprotective and anti-inflammatory effects. However, the poor solubility of triterpenes in both polar and non-polar solvents as well as expensive purification procedures have prevented the large-scale isolation of these compounds for medicinal purposes. Here, we describe a novel quantitative extraction method of triterpenes from the outer bark of birch (Betula species) in which betulin, a lupan triterpene, predominates. The resulting highly purified triterpene extract (TE) in the form of a dry powder contains betulin as the major compound, but also betulinic acid, lupeol, erythrodiol and oleanolic acid. We have found that this TE is able to form an oleogel, thus providing an opportunity for the topical application of pharmacologically relevant amounts of triterpenes. Furthermore, we have investigated the TE in comparison to its major isolated compounds in cell culture experiments with human immortalized keratinocytes and skin cancer cells. We could demonstrate dose-dependent cytotoxic and apoptosis-inducing effects of TE and betulin. These experimental data support the notion from a previous clinical study that TE from the outer bark of birch might represent a new tool for the topical treatment of skin cancer and skin cancer precursors like actinic keratoses.
90 citations
TL;DR: Three new lupane triterpenes were isolated from the root bark of Maytenus cuzcoina and the leaves of MayTenus chiapensis, and exhibited potent inhibitory effects on NO and prostaglandin E(2) production in mouse macrophages stimulated with bacterial endotoxin.
TL;DR: Three new triterpene glycosides are isolated as active compounds causing morphological abnormality of Pyricularia oryzae mycelia and showed in vitro cytotoxicity against two human tumor cell lines.
Abstract: Bioassay-guided fractionation of the active n-BuOH extract of the sea cucumber Holothuria fuscocinerea resulted in the isolation of three new triterpene glycosides, fuscocinerosides A (1), B (2), and C (3), along with two known glycosides, pervicoside C (4) and holothurin A (5), as active compounds causing morphological abnormality of Pyricularia oryzae mycelia. Compounds 1-5 possess the same tetrasaccharide moiety, 3-O-methyl-beta-D-glucopyranosyl-(1-->3)-beta-D- glucopyranosyl-(1-->4)-beta-D-quinovopyranosyl-(1-->2)-4-O-sodiumsulfato-beta-D-xylopyranosyl, linked to C-3 of holostane triterpene aglycones that differ in their side chains and 17-substituents. Their structures were elucidated by extensive spectral studies as well as chemical evidence. All the glycosides showed in vitro cytotoxicity against two human tumor cell lines.
TL;DR: Three new cucurbitane-type triterpene called karavilagenins A, B, and C and five new cucurbane- type triterPene glycosides called kARavilosides I, II, III, IV, and V were isolated from the dried fruit of Sri Lanka.
Abstract: Three new cucurbitane-type triterpene called karavilagenins A, B, and C and five new cucurbitane-type triterpene glycosides called karavilosides I, II, III, IV, and V were isolated from the dried fruit of Sri Lanka Momordica charantia L. (Cucurbitaceae) together with two known cucurbitane-type triterpenes, 19(R)-methoxy-5beta,19-epoxycucurbita-6,23-dien-3beta,25-diol and 5,19-epoxycucurbita-6,23-diene-3,25-diol, and nine known cucurbitane-type triterpene glycosides, goyaglycosides-b, -c, and -d, and momordicosides F1, F2, G, I, K, and L. The structures of karavilagenins and karavilosides were elucidated on the basis of chemical and physicochemical evidence.
TL;DR: Twenty-five triterpene acids isolated from the MeOH extract of the resin of Boswellia carteri (Burseraceae) exhibited potent cytotoxic activities against three human neuroblastoma cell lines, IMR-32, NB-39, and SK-N-SH in vitro.
Abstract: Fifteen triterpene acids, viz., seven of the beta-boswellic acids (ursane-type) (1-7), two of the alpha-boswellic acids (oleanane-type) (8, 9), two of the lupeolic acids (lupane-type) (10, 11), and four of the tirucallane-type (12-14, 16), and two cembrane-type diterpenes (17, 18), isolated from the MeOH extract of the resin of Boswellia carteri (Burseraceae), together with a triterpene acid 15 (the acetyl derivative of 14), were examined for their inhibitory effects on the induction of Epstein-Barr virus early antigen (EBV-EA) by 12-O-tetradecanoylphorbol-13-acetate (TPA) in Raji cells and on activation of (+/-)-(E)-methyl-2[(E)-hydroxyimino]-5-nitro-6-methoxy-3-hexemide (NOR 1), a nitrogen oxide (NO) donor, and cytotoxic activities against three human neuroblastoma cell lines, IMR-32, NB-39, and SK-N-SH in vitro. On evaluation against the EBV-EA activation induced by TPA, seven compounds, 2, 10, 11, and 13-16, showed potent inhibitory effects on EBV-EA induction. Upon evaluation against activation of NOR 1, five compounds, 7, 13, and 14-16, showed potent inhibitory effects. Further, fifteen compounds, 1-7, 9-11, 13-15, 17, and 18, exhibited potent cytotoxic activities with IC(50) values of 4.1-82.4 muM against all of the three human neuroblastoma cells tested.
TL;DR: While 3beta,6beta-dihydroxy-11-oxo-olean-12-en-28-oic acid exhibited the least effective growth inhibition among these triterpenoids, it induced HL-60 cells to undergo differentiation as measured by an NBT reduction assay.
Abstract: Four new triterpenoids, 6beta-hydroxy-3-oxo-11alpha,12alpha-epoxyolean-28,13beta-olide (1), 3beta,6beta-dihydroxy-11alpha,12alpha-epoxyolean-28,13beta-olide (2), 3beta,6beta-dihydroxy-11-oxo-olean-12-en-28-oic acid (3), and 3beta-hydroxy-12-oxo-13Halpha-olean-28,19beta-olide (4), and five known triterpenes, 19alpha-hydroxy-3-oxo-olean-12-en-28-oic acid (5), 6beta-hydroxy-3-oxo-olean-12-en-28-oic acid (6), sumaresinolic acid (7), siaresinolic acid (8), and oleanolic acid (9), were isolated from the resin of Styrax tonkinensis. The structures of these triterpenoids were determined by physicochemical and spectroscopic methods. The configuration of compound 4 was confirmed by X-ray crystallographic analysis. All these triterpenoids inhibited HL-60 cell growth with IG(50) values ranging from 8.9 to 99.4 microM. Oleanolic acid (9) was the most effective antiproliferative agent, with an IG(50) value of 8.9 microM. While 3beta,6beta-dihydroxy-11-oxo-olean-12-en-28-oic acid (3) exhibited the least effective growth inhibition among these triterpenoids, it induced HL-60 cells to undergo differentiation as measured by an NBT reduction assay.
TL;DR: This review summarizes the chemical features of saponins from Medicago species and their biological activity, with particular attention to their antimicrobial, insecticidal, allelopathic and cytotoxic effects.
Abstract: Naturally occurring saponins are a large group of triterpene and steroid glycosides characterized by several biological and pharmacological properties. The Medicago genus represents a valuable sour...
Journal Article•
TL;DR: The structures of the compounds were elucidated by high field 1D and 2D NMR and EIMS spectroscopies as mentioned in this paper, and the structures of these compounds were shown to have similar properties to those of triterpene acids.
Abstract: From the aerial parts of Galium tortumense Ehrend & Schonb.-Tem., 8 iridoid glycosides, a flavonol glycoside, a oleanane-type triterpene acid, an ursan-type triterpene acid and a sterol were isolated. The structures of the compounds were elucidated by high field 1D and 2D NMR and EIMS spectroscopies.
TL;DR: Results indicate that 3-hydroxyl group and a carboxyl group in this type of triterpenes may be required for the activity, while addition of one more hydroxyl Group at C-6 or C-24 may be responsible for a loss of activity.
TL;DR: The results indicate that the substitution of hydroxy groups on the ursane-type triterpenes is responsible for the loss of activity, and thus 1 and 2 possessing only one or two hydroxy Groups can be potential PTP1B inhibitors.
Abstract: Inhibition of protein tyrosine phosphatase 1B (PTP1B) has been proposed as a therapy for treatment of type 2 diabetes and obesity. Bioassay-guided fractionation of the MeOH extract of the leaves and stems of Symplocos paniculata (Thunb.) Miq. (Symplocaceae), using an in vitro PTP1B inhibitory assay, resulted in the isolation of three ursane-type triterpenes, ursolic acid (1), corosolic acid (2) and 2alpha,3alpha,19alpha,23-tetrahydroxyurs-12-en-28-oic acid (3). Compounds 1-3 inhibited PTP1B with IC (50) values of 3.8 +/- 0.5, 7.2 +/- 0.8 and 42.1 +/- 1.5 microM, respectively. Kinetic studies suggest that 1 is a competitive inhibitor with a K(i) value of 2.0 microM, whereas 2 is a mixed-type inhibitor of PTP1B. Our results indicate that the substitution of hydroxy groups on the ursane-type triterpenes is responsible for the loss of activity, and thus 1 and 2 possessing only one or two hydroxy groups can be potential PTP1B inhibitors.
TL;DR: In this article, three triterpenoid saponins, acanthopanaxosides A (1), B (7), and C (13), were isolated from the leaves of Acanthopsanax senticosus, together with 12 known saponin compounds.
Abstract: Three new triterpenoid saponins, acanthopanaxosides A (1), B (7), and C (13), were isolated from the leaves of Acanthopanax senticosus, together with 12 known saponins. The structures of these new saponins were established as 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-30-nor-olean-12,20(29)-dien-28-oic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-6-O-acetyl-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (1), 3-O-beta-D-glucopyranosyl-(1-->2)-alpha-L-arabinopyranosyl oleanolic acid 28-O-alpha-L-rhamnopyranosyl-(1-->4)-6-O-acetyl-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranosyl ester (7), and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-alpha-L-arabinopyranosyl-3beta-hydroxyolean-12-ene-28,29-dioic acid (13), on the basis of spectroscopic analysis and chemical degradation. Among the known compounds, sessiloside and tauroside H1 are reported for the first time from A. senticosus. The biological activity of compounds 1-15 was examined against pancreatic lipase. Ciwujianoside C1 (6), tauroside H1 (11), 3-O-alpha-rhamnopyranosyl-(1-->2)-alpha-arabinopyranosyl mesembryanthemoidigenic acid (12), acanthopanaxoside C (13), sessiloside (14), and chiisanoside (15) inhibited pancreatic lipase activity in vitro. In turn, ciwujianosides C2 (3), D2 (5), C4 (8), and C3 (10) and hederasaponin B (9) enhanced this enzyme.
TL;DR: The multiple amino acid sequence alignment of a conserved region suggests that the LAS of different eukaryotic lineages emerged from the ancestral CAS by convergent evolution.
Abstract: Sterols, essential eukaryotic constituents, are biosynthesized through either cyclic triterpenes, lanosterol (fungi and animals) or cycloartenol (plants). The cDNA for OSC7 of Lotus japonicus was shown to encode lanosterol synthase (LAS) by the complementation of a LAS-deficient mutant yeast and structural identification of the accumulated lanosterol. A double site-directed mutant of OSC7, in which amino acid residues crucial for the reaction specificity were changed to the cycloartenol synthase (CAS) type, produced parkeol and cycloartenol. The multiple amino acid sequence alignment of a conserved region suggests that the LAS of different eukaryotic lineages emerged from the ancestral CAS by convergent evolution.
TL;DR: Five new cucurbitane-type triterpenes have been isolated from the methanol extract of the stems of Momordica charantia by spectroscopic methods.
Abstract: Five new cucurbitane-type triterpenes, (23E)-25-methoxycucurbit-23-ene-3β,7β-diol (1), (23E)-cucurbita-5,23,25-triene-3β,7β-diol (2), (23E)-25-hydroxycucurbita-5,23-diene-3,7-dione (3), (23E)-cucurbita-5,23,25-triene-3,7-dione (4), and (23E)-5β,19-epoxycucurbita-6,23-diene-3β,25-diol (5), together with one known triterpene, (23E)-5β,19-epoxy-25-methoxycucurbita-6,23-dien-3β-ol (6), have been isolated from the methanol extract of the stems of Momordica charantia. The structures of the new compounds were elucidated by spectroscopic methods.
TL;DR: In this article, a new triterpen was identified as the acid, 1α,19α-dihydroxyursan-28-oic, and named annurcoic acid.
TL;DR: The yeast transformant accumulated tricyclic triterpene, (3S,13R)-malabarica-17,21-dien-3,14-diol (arabidiol), whose structure was determined by NMR and MS analyses.
TL;DR: It is suggested that the free hydroxyl at C‐3 and the polarity of C‐28 are the most influential structural features for determining the in vitro trypanocidal activity of triterpenes.
Abstract: Triterpene acids, including ursolic acid (1), urjinolic acid (4) and oleanoic acid (5) along with a mixture of 2α-hydroxyursolic acid (2) and maslic acid (3) were isolated from methylene chloride extracts of the Miconia sellowiana and M. ligustroides species and their activities against the trypomastigote blood forms of Trypanosoma cruzi were evaluated. The potassium salt derivative of ursolic acid (1a) was also tested. The in vitro assays showed that compounds 1, 5 and 1a were the most active (IC50 17.1 µm, 12.8 µm and 8.9 µm, respectively). In contrast, a mixture of 2 plus 3, that exhibit a hydroxyl at C-2 and C-3, is much less potent than a mixture of 1 and 5 (IC50 48.5 µm and 11.8 µm, respectively). In the same manner, compound 4, that differs from 5 by two additional hydroxyl groups (at C-2 and C-23) displayed weak trypanocidal activity (IC50 76.3 µm) when compared with the other triterpenes. These results suggest that the free hydroxyl at C-3 and the polarity of C-28 are the most influential structural features for determining the in vitro trypanocidal activity of triterpenes. In vivo assays were also undertaken for the most active compounds 1, 1a and the mixture of 1 plus 5. The most significant reduction in parasite number in the parasitemic peak were obtained for compound 1 and its salt derivative 1a (75.7% and 70.4%, respectively). Moreover, the survival time was increased for all the treated animals. Copyright © 2006 John Wiley & Sons, Ltd.
TL;DR: Six new triterpenoidal compounds named heteroclitalactones A-E, as well as heteroclic acid, which was isolated for the first time from a natural source, and the six known compounds schisanlactone E, cycloartenone, schisandronic acid, nigranoic acid, changnanic acid and schisanLactone B, respectively showed moderate cytotoxic activity against the human tumor cell lines.
Abstract: Phytochemical investigations of the stem of Kadsura heteroclita (Roxb) Craib (Schizandraceae) resulted in the isolation and structure elucidation of six new triterpenoidal compounds named heteroclitalactones A-E (1-5) as well as heteroclic acid (6) and heteroclitalactone F (7), which was isolated for the first time from a natural source, and the six known compounds schisanlactone E (8), cycloartenone (9), schisandronic acid (10), nigranoic acid (11), changnanic acid (12) and schisanlactone B (13), respectively. The structures of these compounds were characterized by extensive 1D and 2D NMR spectral analyses. The majority of these triterpenoids showed moderate cytotoxic activity against the human tumor cell lines Bel-7402, BGC-823, MCF-7 and HL-60. Among the compounds tested, heteroclitalactone D (4) showed the strongest cytotoxic activity against the HL-60 cells with an IC50 of 6.76 microM.
TL;DR: A detailed phytochemical study on the 70% aqueous ethanol extract of stems of Akebia trifoliata (Thunb.) Koidz.
TL;DR: Eight new tyrosinase inhibitory cycloartane triterpenoids have been discovered from the methanol extract of the whole plant of Amberboa ramosa (Roxb.) Jafri, which is a member from the Compositae family.
TL;DR: A total of fourteen constituents in the crude extract were structurally characterized on the basis of their retention time and tandem mass spectrometric analysis, including five pairs of naturally occurring isomers, except one known saponin formerly obtained, and the other constituents were new compounds.
TL;DR: The saponin showed in vitro antileishmanial activity against Leishmania donovani (strain AG 83) and was characterized as 3-O-beta-D-glucopyranosyl-2 alpha,3beta-dihydroxy-taraxast-20-en-28-oic acid.