Biomedical subjects

Catherine Lavaud

Publications and source records attributed to Catherine Lavaud.

17 recordsLinked to original sources

PubMed2006

Triterpenoid saponins from the stem bark of Caryocar villosum.

Five triterpenoid saponins, caryocarosides II-22 (3), III-22 (4), II-23 (5), III-23 (6), and II-24 (7), have been isolated from the methanol extract of the stem bark of Caryocar villosum, along with two known saponins (1-2). The seven saponins are glucuronides of hederagenin (II) or bayogenin (III). Caryocaroside II-24 (7) is an unusual galloyl ester saponin acylated on the sugar chain attached to C-28, the 3-O-alpha-L-rhamnopyranosyl-(1-->3)-beta-D-galactopyranosyl-(1-->3)-beta-D-glucuronopyranosyl hederagenin-28-O-[2-O-galloyl-beta-D-glucopyranosyl] ester. The structures of the saponins were established on the basis of extensive NMR ((13)C, (1)H, COSY, TOCSY, HSQC, HMBC and ROESY) and ESI-MS studies. The cytotoxic activity of saponins 2 and 3 was evaluated in vitro against human keratinocytes. The DOPA-oxidase inhibition and the lipolytic activities were evaluated ex vivo using an explant of human adipose tissue.

Adipose Tissue↗

PubMed2006

Triterpenoid saponins from the fruits of Caryocar glabrum.

Twenty-one new triterpenoid saponins, named caryocarosides (1-21), glycosides of 2beta-hydroxyoleanolic acid, hederagenin, bayogenin, and gypsogenic acid, have been isolated from the fruits of Caryocar glabrum along with nine known triterpenoid saponins (22-30) that are described for the first time from a plant in the Caryocaraceae. Their structures were established by 1D and 2D NMR techniques ((13)C, COSY, TOCSY, HSQC, HMBC, and ROESY experiments), ESIMS, and acid hydrolysis. The isolated compounds could be classified into two series: glucosides (1-8, 22, 27, and 30) derived from the 3-O-monoglucoside and glucuronides (9-21, 23-26, 28, and 29) derived from the 3-O-monoglucuronide. In 22 of the saponins (1-8, 12-22, and 24-26), a galactose moiety was linked to C-3 of a glucuronic acid or a glucose moiety. The galactose was substituted in position 3 by a second galactose unit (6, 7, 20, and 21) or by a xylose unit (8). Seven saponins (4, 5, 16-19, and 26) were found to be bidesmosides with one glucose unit linked to C-28 of the aglycon. The hemolytic activity of the major saponins (2, 3, 5, 12-15, 17, 24, and 28) was measured on sheep erythrocytes in order to establish structure-activity relationships based on the type of sugar attached to the aglycon and on the structure of this aglycon.

Animals↗

PubMed2006

Triterpenoid saponins from the fruits of Caryocar villosum.

Fourteen new triterpenoid saponins (1-14) were isolated from the methanol extract of the fruits of Caryocar villosum along with 10 known saponins. Their structures were established on the basis of extensive NMR (1H, 13C, COSY, TOCSY, ROESY, HSQC, and HMBC) and ESIMS studies. The toxicity of the methanolic extracts of the peel and the pulp of fruits and the crude saponin fraction of the peel was assessed using the Artemia salina test. The antimicrobial activities of caryocarosides IV-21 (14), II-1 (16), III-1 (17), and IV-9 (20) and of saponin 23 were also studied in vitro on Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Mycobacterium smegmatis, and Enterococcus faecalis bacteria.

Animals↗

PubMed2005

Saponins from the seeds of Mimusops laurifolia.

Nine saponins were isolated from the seeds of Mimusops laurifolia. Their structures were established using one- and two-dimensional NMR spectroscopy and mass spectrometry. Three of them are identified as: 3-O-(beta-d-apiofuranosyl-(1-->3)-beta-d-glucuronopyranosyl)-28-O-(alpha-l-rhamnopyranosyl-(1-->3)-beta-d-xylopyranosyl-(1-->4)-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-arabinopyranosyl)-16alpha-hydroxyprotobassic acid, 3-O-(beta-d-glucopyranosyl-(1-->3)-beta-d-glucopyranosyl)-28-O-(alpha-l-rhamnopyranosyl-(1-->3)-beta-d-xylopyranosyl-(1-->4)-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-arabinopyranosyl)-16alpha-hydroxyprotobassic acid and 3-O-(beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl-(1-->6)-beta-d-glucopyranosyl)-28-O-(alpha-l-rhamnopyranosyl-(1-->3)-beta-d-xylopyranosyl-(1-->4)-alpha-l-rhamnopyranosyl-(1-->2)-alpha-l-arabinopyranosyl)-16alpha-hydroxyprotobassic acid.

Mimusops↗

PubMed2005

Acylated farnesyl diglycosides from Guioa crenulata.

Chemical investigation of the methanol extract of the leaves of Caledonian Guioa crenulata led to the isolation and characterisation of four farnesyl diglycosides, crenulatosides A, B, C and D, along with three known flavonol glycosides and one known trimeric proanthocyanidin possessing a doubly linked structure. The structures of these compounds were determined on the basis of spectroscopic studies and chemical evidence. The ethanol and ethyl acetate extracts of the leaves exhibited no cytotoxic activity and no inhibition of acetylcholinesterase.

Acylation↗

PubMed2005

Haemolytic acylated triterpenoid saponins from Harpullia austro-caledonica.

Eight new acylated triterpenoid saponins were isolated from the stem bark of Harpullia austro-caledonica along with the known harpuloside (9). Their structures were established using 1D and 2D NMR and mass spectrometry as 3-O-beta-D-galactopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloylbarringtogenol C (1), 3-O-alpha-L-rhamnopyranosyl-(1-->3)-[beta-D-galactopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloyl barringtogenol C (2), 3-O-alpha-L-arabinofuranosyl-(1-->3)-[beta-D-galactopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloylbarringtogenol C (3), 3-O-alpha-L-arabinofuranosyl-(1-->2)-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloylprotoaescigenin (4), 3-O-alpha-L-arabinofuranosyl-(1-->3)-[alpha-L-arabinofuranosyl-(1-->2)]-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloyl protoaescigenin (5), 3-O-alpha-L-arabinofuranosyl-(1-->3)-[beta-D-xylopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloylprotoaescigenin (6), 3-O-alpha-L-arabinofuranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloylprotoaescigenin (7), 3-O-beta-D-xylopyranosyl-(1-->2)-beta-D-glucuronopyranosyl-21 beta, 22 alpha-di-O-angeloylprotoaescigenin (8). The EtOH extract of the stem bark showed in vitro cytotoxic activity against KB cells (90% at 10 microg/ml). At a concentration of 5 microg/ml, the saponin mixture showed haemolytic activity and caused 100% haemolysis of a 10% suspension of sheep erythrocytes.

Animals↗

PubMed2005

Triterpenoid saponin anthranilates from Albizia grandibracteata leaves ingested by primates in Uganda.

Three new oleanane-type triterpene saponins (1-3), named grandibracteosides A-C, were isolated from the methanolic extract of leaves of Albizia grandibracteata, a species consumed by primates in the Kibale National Park, Uganda. The structures of the saponins were established using 1D and 2D NMR experiments and mass spectrometry and confirmed by acid and alkaline hydrolysis. The crude extract and the pure compounds showed significant inhibitory activity against KB and MCF7 tumoral cell lines in vitro. The compounds are glycosides of acacic acid acylated by an o-aminobenzoyl unit. This is the first report of such ester saponins in dicotyledonous plants. Studies of the primate diet may provide a useful method for finding naturally occurring compounds of medicinal significance.

Albizzia↗

PubMed2005

Saponins from the leaves of Mimusops laurifolia.

Fifteen new bidesmosidic triterpenoid saponins (1-15) were isolated from a methanol extract of the leaves of Mimusops laurifolia. Their structures were established using one- and two-dimensional NMR spectroscopy and mass spectrometry and determined to be bidesmosides of protobassic acid (2-4, 11, 12, and 15) and of 16alpha-hydroxyprotobassic acid (1, 5-10, 13, and 14).

Egypt↗

PubMed2005

Acylphloroglucinol derivatives from Mahurea palustris.

Five new acylphloroglucinol derivatives, mahureones A-E (1, 3-6), have been isolated from the leaves of Mahurea palustris, and their structures determined by spectroscopic means. During the isolation process, several byproducts (7-9) were formed by reaction of one of the isoprenyl side chains with TFA, water, and acetonitrile. All the compounds were assayed for their ability to inhibit human DNA polymerase beta. The most active compounds, mahureones A (1) and D (5), exhibited IC50 values in the 10 microM range.

Clusiaceae↗

PubMed2004

Acetylated glucuronide triterpene bidesmosidic saponins from Symplocos glomerata.

Nine new bidesmosidic 3-O-glucuronide oleanane triterpenoid saponins were isolated from the stem bark of Symplocos glomerata King along with two known saponins, salsoloside C and copteroside E, and two major lignans, (-)-pinoresinol and (-)-pinoresinol-4'-O-beta-D-glucopyranoside. The structures of the new saponins were established using one- and two-dimensional NMR spectroscopy and mass spectrometry as, 3-O-[beta-D-xylopyranosyl(1-->4)-[2-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[beta-D-xylopyranosyl(1-->4)-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[beta-D-xylopyranosyl (1-->4)-[2,3-O-diacetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[alpha-L-arabinopyranosyl(1-->4)-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[alpha-L-arabinopyranosyl (1-->4)-[2-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[[beta-D-xylopyranosyl (1-->2)]-[beta-D-xylopyranosyl (1-->4)]-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[[beta-D-glucopyranosyl (1-->2)]-[beta-D-xylopyranosyl (1-->4)]-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, 3-O-[[beta-D-glucopyranosyl (1-->2)]-[alpha-L-arabinofuranosyl (1-->4)]-[3-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-oleanolic acid, and 3beta-O-[beta-D-xylopyranosyl(1-->4)-[2-O-acetyl]-beta-D-glucuronopyranosyl]-28-O-[beta-D-glucopyranosyl]-morolic acid. The EtOH and EtOAc extracts of the stem bark showed no cytotoxic activity. At a concentration of 370 microg/ml, the saponin mixture showed haemolytic activity and caused 50% haemolysis of a 10% suspension of sheep erythrocytes.

Acetylation↗

PubMed2004

Four new dammarane saponins from Zizyphus lotus.

Five dammarane-type saponins were isolated by means of centrifugal partition chromatography from the leaves of Zizyphus lotus. Their structures were elucidated using a combination of 1D and 2D 1H and 13C NMR spectra and mass spectroscopy. One of these glycosides is the known jujuboside B (5). Three are new jujubogenin glycosides, identified as 3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyljujubogenin-20-O-(2,3,4-O-triacetyl)-alpha-L-rhamnopyranoside (1), 3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranosyljujubogenin-20-O-alpha-L-rhamnopyranoside (2), and 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[(4-sulfo)-beta-D-glucopyranosyl-(1-->3)]-alpha-L-arabinopyranosyljujubogenin (3). The last is a new sulfated derivative of jujubasaponine IV, identified as 3-O-alpha-L-rhamnopyranosyl-(1-->2)-[(4-sulfo)-beta-D-glucopyranosyl-(1-->3)]-beta-D-galactopyranosyl-(20R,22R)-16beta,22:16alpha,30-diepoxydammar-24-ene-3beta,20-diol (4).

Molecular Structure↗

PubMed2004

Alkylated isocoumarins from Pituranthos scoparius.

Two isocoumarins have been isolated from the ethyl acetate extract of the root of Pituranthos scoparius: 3-n-propyl-5-methoxy-6-hydroxy-isocoumarin and 3-n-propyl-5,7-dimethoxy-6-hydroxy-isocoumarin. Their structures were assigned by spectral analysis.

Apiaceae↗

PubMed2003

Bioactive flavonoids of Tanacetum parthenium revisited.

Bio-guided fractionation of an extract from Tanacetum parthenium showing activity as mitotic blocker allowed the isolation and identification of santin 3, jaceidin 2 and centaureidin 1. The latter two closely related flavonols, which, to the best of our knowledge, are isolated here together for the first time, form a mixture difficult to resolve and which is probably the reason for the confusion in the literature regarding their occurrence. Centaureidin 1 had an IC50 of 1 microM while jaceidin 2 and santin 3 were 200 times less active.

Animals↗

PubMed2003

Acylated flavonol glycosides from leaves of Planchonia grandis.

Three acylated flavonol glycosides have been identified from leaves of Planchonia grandis Ridley. They possess kaempferol as aglycone and two triglycosidic chains substituting hydroxyl groups at the 3- and 7-positions. The first glycosidic unit of each chain is esterified by a cis or trans p-coumaric acid. Structural elucidation was achieved by means of UV, NMR and mass spectrometry.

Acylation↗

PubMed2003

Oleanolic glycosides from Pometia ridleyi.

Six triterpenoid saponins were isolated from the stem bark of Pometia ridleyi along with two known saponins, acutoside A and calenduloside C. Their structures were established using one- and two-dimensional NMR and mass spectrometry as 3-O-beta-D-apiofuranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl-, 3-O-beta-D-apiofuranosyl-(1-->3)-alpha-L-arabinopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl-, 3-O-beta-D-apiofuranosyl-(1-->3)-beta-D-galactopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-beta-D-glucopyranosyl-, 3-O-alpha-L-arabinopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl-, 3-O-beta-D-galactopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl-, 3-O-beta-D-apiofuranosyl-(1-->3)-beta-D-galactopyranosyl-(1-->3)-[beta-D-glucopyranosyl-(1-->2)]-alpha-L-arabinopyranosyl-oleanolic acid. The EtOH and EtOAc extracts of the stem bark showed no cytotoxic activity. At a concentration of 23 microg/ml, the saponin mixture showed haemolytic activity and caused 50% haemolysis of a 10% suspension of sheep erythrocytes.

Animals↗

PubMed2002

Triterpenoid saponins and acylated prosapogenins from Harpullia austro-caledonica.

Three new triterpenoid saponins have been isolated from the stem bark of Harpullia austro-caledonica and identified as 24-O-[alpha-L-rhamnopyranosyl-(1->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl-(1->2)-beta-D-glucopyranosyl]-protoaescigenin, 24-O-[alpha-L-rhamnopyranosyl-(1->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl-(1->2)-beta-D-glucopyranosyl]-16-desoxyprotoaescigenin, 24-O-[alpha-L-rhamnopyranosyl-(1->2)-beta-D-glucopyranosyl]-28-O-[beta-D-glucopyranosyl-(1->2)-beta-D-glucopyranosyl]-24-oxo-camelliagenin D. The 21,22-di-O-angeloate esters of protoaescigenin and barringtogenol C were isolated in the acid hydrolysate of the saponin extract together with a new prosapogenin identified as 21beta,22alpha-di-O-angeloyl camelliagenin D. The structures were established using one- and two- dimensional NMR and mass spectrometry.

Acylation↗

PubMed2002

Acylated triterpenoid saponins from the stem bark of Foetidia africana.

Nine new acylated triterpenoid saponins (4-12) were isolated from the stem bark of Foetidia africana. They all possess barringtogenol C as the aglycone, esterified by acetic and/or isovaleric acids. The sugar chain consists of up to three units: D-glucuronic acid (GlcUA) linked to C-3 of the aglycone and substituted by D-galactose (Gal) (at GlcUA C-2) and/or L-rhamnose (Rha) (at GlcUA C-4). The structures were established by acid and alkaline hydrolysis, by NMR experiments including (1)H-(1)H (COSY, HOHAHA, ROESY) and (1)H-(13)C (HSQC, HMBC) spectroscopy, and by mass spectrometry (ESIMS, ESIMS(n)).

Acetates↗