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Phytochemical investigation of the dichloromethane extract of the leaves of Peltophorum pterocarpum, a tropical ornamental tree, led to the isolation of twelve compounds (1-12). One new derivative of peltogynoid ophioglonin (1) and a new 2-phenoxychromone (2) with its 3'-O-β-D-glucoside derivative (3) are described here for the first time. In addition, nine flavonoid derivatives, including peltogynoid ophioglonin (4), were isolated for the first time from this plant. The structures were determined by spectroscopic and chemical methods. Evaluation of the estrogenic activities of 1, 2, and 4 using different model cell systems revealed that 4 was estrogenic and that 2 was largely inactive. Interestingly, 1 was unable to stimulate the proliferation of breast and endometrial cancer cells but exhibited substantial estrogen receptor α-mediated activation of gene expression. This observation indicates that 1 can be further evaluated for its cancer chemopreventive potential.

International audience; The hydrodistilled oil of the aerial parts from Genista quadriflora growing in Algeria was analyzed by gas chromatography-flame ionization detection (GC/FID) and gas chromatography-mass spectrometry (GC/MS). Altogether 222 volatile substances, representing around 77% of the essential oil was identified. The major constituents were the sesquiterpenes muurolan-4,7-peroxide (19.42%), amorpha-4,9-dien-2-ol (10.40%), alpha-cadinol (2.29%), caryophyllene oxide (1.47%) and germacra-4(15),5,10(14)-trien-1-alpha-ol (1.39%). Fatty acids were the second most abundant compounds of the essential oil detected with dodecanoic acid (lauric) (3.14%), hexadecanoic acid (palmitic) (2.49%) and tetradecanoic acid (myristic) (1.12%) as main components. The volatile oil was screened in vitro for antibacterial and antifungal activities using dilution and disc diffusion methods. Thus, the crude essential oil exhibited a marked antifungal activity against Fusarium oxysporun and a significant inhibition activity was registered towards a Gram-negative bacterium Proteus mirabilis. Substantial antibacterial activity was also recorded against Gram-positive bacteria with MIC: 0.9 +/- 0.1 and 1.7 +/- 0.3 mg/ml for Staphylococcus aureus suggesting the possibility to use of G. quadriflora essential oil in the development of new drugs for treatment of infectious diseases.

A phytochemical study of Asplenium ruta-muraria L. (Aspleniaceae) led to the isolation of a new caffeic acid glycoside, 2-O-caffeoyl-β-D-fructofuranosyl-(2 → 1)-α-D-glucopyranoside and an (α, β)-isomeric pair of 2E-caffeoyl-D-glucopyranoside, together with kaempferol-3-O-β-D-[6-E-caffeoyl-β-D-glucopyranosyl-(1 → 2)glucopyranoside]-7-O-β-D-glucopyranoside, 1-O-caffeoyl glycoside, sucrose, diploptene and β-sitosterol. Their structures were established by means of MS and capillary NMR techniques. Additionally, aromatase inhibitory activity of the extracts and phenolic compounds was evaluated.

Phytochemical investigation of dichloromethane (DCM) extract from the stems of Paragonia pyramidata var. pyramidata L. Rich. (Bur.) resulted in the isolation and characterization of two new triterpenoids 3β,19β-dihydroxylup-12, 20(29)-diene-28-oic acid (1) and 3β,19β-dihydroxylup-12-en-28-oic acid (2), three known triterpenoids lupeol (3), spinosic acid A (4) and oleanolic acid (5), together with four known steroids (20R)-22E-24-ethylcholesta-4,22-dien-3-one (6), (20R)-24-ethylcholest-4-en-3-one (7), stigmasterol (8) and β-sitosterol (9). HREIMS, GC-MS and NMR experiments including HSQC, HMBC, COSY and NOESY were used for the determination of the structures and NMR spectral assignments. This is the first report about the chemical constituents for this plant.

Three tropane alkaloids, named schizanthines N, O, and P (1−3), have been isolated from the crude alkaloid extract of the endemic Chilean plant Schizanthus tricolor. On the basis of extensive NMR studies and MS fragmentation analysis, their structures were determined to be 3α-(E)-4-hydroxysenecioyloxy-6β-angeloyloxytropane (1), 3α-(E)-4-hydroxysenecioyloxy-6β-senecioyloxytropane (2), and 3α-mesaconyloxy-6β-senecioyloxytropane (3). Compounds 1 and 2 are the first isomeric alkaloids in the tropane series possessing a hydroxysenecioyl substituent as an esterifying moiety.

The methanol extract from the stem bark of Diospyros sanza-minika as well as five norbergenin derivatives isolated from this crude extract were evaluated for their in vitro activity against Plasmodium falciparum K1 and cytotoxicity on MRC-5 cells. 4-O-(3'-methylgalloyl)norbergenin was found to be the most potent compound (IC(50) 0.6 μg/mL; CC(50) 24.7 μg/mL), followed by 4-O-galloylnorbergenin (IC(50) 3.9 μg/mL; CC(50) > 64 μg/mL) and 11-O-p-hydroxy-benzoyl-norbergenin (IC(50) 4.9 μg/mL; CC(50) > 64 μg/mL). Norbergenin and 4-O-syringoylnorbergenin were inactive (IC(50) > 32 μg/mL; CC(50) > 64 μg/mL). The antimalarial activity of the pure constituents and of the methanol extract from the stem bark of Diospyros sanza-minika is reported for the first time. The results provide interesting baseline information for the potential use of the crude extract well as some of the isolated compounds in the search for novel antimalarial compounds.

Introduction – Rhodiola rosea is a broadly used medicinal plant with largely unexplored natural variability in secondary metabolite levels. Objective – The aim of this work was to develop a non-target procedure for 1H NMR spectroscopic fingerprinting of rhizome extracts for pattern recognition analysis and identification of secondary metabolites responsible for differences in sample composition. To achieve this, plants from three different geographic areas (Swiss Alps, Finland, and Altai region in Siberia) were investigated. Results – A sample preparation procedure was developed in order to remove polymeric polyphenols as the 1H NMR analysis of low-molecular-weight metabolites was hampered by the presence of tannins. Principal component analysis disclosed tight clustering of samples according to population. PCA models based on the aromatic region of the spectra showed that the first two components reflected changes in the content of salidroside and rosavin, respectively, the rosavin content being negatively correlated to that of rhodiocyanoside A and minor aromatics. Score plots and non-parametric variance tests demonstrated population-dependent changes according to harvest time. Data consistency was assessed using score plots and box-and-whisker graphs. In addition, a procedure for presenting loadings of PCA models based on bucketed data as high-resolution plots, which are reminiscent of real 1H NMR spectra and help to identify latent biomarkers, is presented. Conclusion – This study demonstrated the usefulness of the established procedure for multivariate non-target 1H NMR metabolic profiling of Rhodiola rosea. Copyright © 2010 John Wiley & Sons, Ltd.

Polygonum cuspidatum Sieb. and Zucc., a traditional Chinese medicine is now a wide-spread invasive neophyte in Europe and America. The novel weapon hypothesis states that some invasive weed species owe part of their success as invaders to allelopathy mediated by some allelochemicals. Previous HPLC/UV/ESI-MS analysis showed that the constituents of the roots of P. cuspidatum from China were obviously different from the species collected in Switzerland (present as an invasive neophyte) with respect to piceatannol glucoside, resveratroloside and some proanthocyanidin. This work isolated these special constituents from the invasive plant and studied their allelopathy effect, as well as the related structures by the seedling and growing model of Lepidium sativum (garden cress, Brassicaceae). The results revealed that stilbenes as piceatannol glucoside, resveratroloside and proanthocyanidins as catechin, epicatechin from this plant were comparatively stronger allelochemicals than the reported allelochemical (−)-catechin, which may partly explain the invasive behavior of this plant in Europe.

Three new norbergenin derivatives, 11-O-p-hydroxybenzoylnorbergenin, 4-O-(3′-methylgalloyl)norbergenin and 4-O-syringoylnorbergenin were isolated from the stem bark of Diospyros sanza-minika, along with three known compounds: norbergenin, 4-O-galloylnorbergenin and quercitol. Their structures were established on the basis of 1D and 2D NMR experiments and mass spectrometry. Some of the above compounds showed radical scavenging properties in a DPPH solution assay.

Extracts of Withania adpressa Coss. (Solanaceae), a medicinal plant endemic to Moroccan Sahara, were tested for their cytotoxicity towards a panel of cancer cell lines (Hep2, HT29, RD, Vero and MDCK), using the (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) [MTT assay, Sigma-Aldrich]. The bioassay-guided fractionation of this plant extracts results a novel withanolide 14α,15α,17β,20β-tetrahydroxy-1-oxo-(22 R )-witha-2,5,24-trienolide and the already identified withanolides F and J extract, semi-purified fractions and pure compounds exhibits potent cytotoxicity against human cancer cell lines tested, in dose-dependant manner. Morphological features of treated Hep2 cells with the novel withanolide and characteristic DNA fragmentation revealed that the cytotoxicity was due to induction of apoptosis. Taken together, the results suggest that withanolides from W . adpressa Coss. hold potential as antiproliferative agents.

Crude extracts of roots and stems of Polygonum cuspidatum Sieb. and Zucc. and Polygonum sachalinensis F. Schmidt ex Maxim from China and Switzerland were analyzed by online HPLC/UV/ESI-MS to ascertain the phytochemical differences between the original and invasive exotic varieties. A total of 36 constituents were identified by comparing their retention times, UV data, mass spectra with those of standards or with literature data. Certain constituents, such as flavanol gallate dimers, were reported for the first time from these species. The relative quantities of the major compounds (emodin glucoside, piceid, resveratroloside and piceatannol glucoside) differed in the samples of the Polygonum species from China and from Switzerland. Phenylpropanoid glucosides were the main constituents of the roots and stems of P. sachalinensis , while the roots of P. cuspidatum were characterized by the presence of stilbenes and anthraquinones.

A novel molluscicide against Pomacea canaliculata snails (Golden apple snail, GAS) based on quinoa saponins (Chenopodium quinoa) is presented. Quinoa is a pseudocereal extensively cultivated and consumed in Bolivia and Peru. The external husk of the grains is removed prior to human consumption due to the bitter taste imparted by their high saponin content (predominantly bidesmosidic saponins), and constitutes a by-product with no commercial value. When tested against GAS, quinoa husks showed no activity up to 121 ppm product (approximately 35 ppm saponins). To increase their molluscicidal properties, the husks were treated with alkali to convert bidesmosidic saponins to more active monodesmosides. This product killed 100% GAS under laboratory conditions at 24 h at approximately 33 ppm product. Surprisingly no toxicity to fish, such as goldfish or tilapia, was observed up to the highest concentration tested (e.g., 54 ppm product). This is a main advantage in relation to available commercial molluscicides that kill fish at product doses lower than those that kill GAS (e.g., niclosamide). The product was also tested preliminary under field conditions in Northern Argentina with similar GAS mortality results. A preliminary LC/ESI–MS/MS study revealed that the husks contained a mixture of known and novel bidesmosidic and monodesmosidic saponins. However, the alkali treated husks did not contain monodesmosidic saponins as expected, but large molecular weight saponin derivatives, probably formed between the saponins and other compounds present in the quinoa hulls under alkaline conditions. Due to the complex nature of these compounds, no direct relationship could be established between product efficacy and a higher content of monodesmosidic saponins. The results suggested that the molluscicidal properties are probably related to the formation of more hydrophobic compounds after alkaline treatment that have higher affinity with the cholesterol present in GAS gills.

In order to find some medicinal value for invasive neophytes, inhibition of acetylcholinesterase of Reynoutria sachalinensis F. Schmidt ex Maxim. (Polygonaceae), Polygonum cuspidatum Siebold. Zucc. (Polygonaceae), Heracleum mantegazzianum Sommier Levier (Apiaceae), Buddleja davidii Franch. (Buddlejaceae), and Ambrosia artemisiifolia L. (Asteraceae) was prescreened by a bioautographic TLC assay. Activity was found in the methanol extract of the leaves of the common ornamental bush B. davidii. Its fractionation by centrifugal partition chromatography led to the isolation of linarin as the most active compound. While extracts of Buddleja nitida Benth. (Buddlejaceae) from Panama were inactive, some constituents were identified on the basis of a comparison with B. davidii by HPLC-MS/MS. Structure-activity relationships of linarin and related flavonoids were investigated. For this purpose, fortunellin and tilianin were prepared by methylation reactions. It appears that the structural elements important for acetylcholinesterase inhibition are not only the 4' -OMe group, but also the 7-substituted sugar and the pattern of substitution on the B-ring.

From the leaves of Withania adpressa, a plant endemic to Sahara of Morocco and Algeria, the novel steroidal lactone (22R)-14 alpha;,15 alpha;,17ß,20ß-tetrahydroxy-1-oxowitha-2,5,24-trien-26,22-olide (= (15S,17S)-14,15,17,20-tetrahydroxy-22,26-epoxyergosta-2,5,24-triene-1,26-dione; 1), was isolated, along with three known compounds, withanolides F (2), J (3), and oleanolic acid. Their structures were mainly solved by in-depth 1D- and 2D-NMR (including ADEQUATE) experiments, as well as by HR-MS analyses and chemical evidence.

The family Gentianaceae includes about 1700 species over 90 genera. These plants are known to biosynthesise, in particular, rare polyphenolic pigments known as xanthones. They also produce flavonoids, as well as monoterpene glycosides (secoiridoids) which are their bitter principles. Numerous phytochemical studies have involved these constituents due to their pharmacological and chemotaxonomic relevance. The strategies used for the isolation of the different constituents of the Gentianaceae as well as their chemical characterisation are discussed, and different analytical methods (LC-MS, LC-UV-PDA and LC-NMR) used for the profiling of these constituents in different species of the Gentianaceae are presented. Examples are also given how these approaches are used to establish chemotaxonomic relationships between species with discussion on chemotaxonomic aspects mainly focused on two subtribes, the Gentianinae and Swertiinae.

A fruit pulp extract of Detarium microcarpum showed inhibition of the growth of the plant pathogenic fungus Cladosporium cucumerinum and of the enzyme acetylcholinesterase, implicated in Alzheimer's disease. Fractionation of this extract led to the isolation of four new clerodane diterpenes, 3,4-epoxyclerodan-13E-en-15-oic acid ( 1), 5 alpha, 8 alpha-(2-oxokolavenic acid) ( 2), 3,4-dihydroxyclerodan-13E-en-15-oic acid ( 4), and 3,4- dihydroxyclerodan-13Z-en-15-oic acid ( 5). Also isolated were 2-oxokolavenic acid ( 3) and copalic acid ( 6). Structure elucidation of the compounds was carried out by spectroscopic data interpretation and by the X-ray crystallography of 2 and 4. Three of the new clerodane diterpenes ( 1, 2, and 5) showed both antifungal activity and inhibition of acetylcholinesterase, and 3 showed a slight inhibition of this enzyme.

Nine new tropane alkaloids substituted by a methylpyrrole moiety were isolated from the bark of Erythroxylum vacciniifolium, a Brazilian endemic plant used in traditional medicine and locally known as catuaba. All compounds were elucidated as tropanediol or -triol alkaloids esterified by at least one 1-methyl-1H-pyrrole-2-carboxylic acid. One of the isolated compounds was identified as a tropane alkaloid N-oxide. Their structures were determined by high-resolution mass spectrometry and multidimensional NMR spectroscopy.

Activity-guided isolation of antifungal, antibacterial, and antioxidant compounds from the dichloromethane extract of the aerial parts of Eriophorum scheuchzeri led to the isolation of eight flavonoids. Three isoflavones and one flavanone are new natural compounds. The isolation of the bioactive compounds was performed by centrifugal partition chromatography. Fractions and pure compounds were monitored by a direct TLC bioautographic assay. Their structures were elucidated by spectroscopic and chemical methods.

The dichloromethane extract of the aerial parts of Blumea gariepina (Asteraceae) was shown to be active against the phytopathogenic fungus Cladosporium cucumerinum and to inhibit acetylcholinesterase. In order rapidly to identify the active principles, the crude extract was analysed by on-flow HPLC-H-1-NMR. HPLC-micro-fractionation was performed and all peaks collected were submitted to assays against C. cucumerinum and acetylcholinesterase. By this means, the biological activities could be efficiently associated with selected HPLC peaks. Complementary on-line structural data for all peaks of interest in the crude extract were obtained from HPLC-MS and from HPLC-UV with post-column addition of UV shift reagents. This chemical screening strategy with integrated bioassays permitted the on-line identification of a number of constituents and gave useful information for an efficient isolation procedure. Copyright (C) 2005 John Wiley & Sons, Ltd.

In a search for potential acetylcholinesterase (AChE) inhibitors, the ethanol extract of the bulbs of Crinum X powellii (Amaryllidaceae) was found to demonstrate a marked inhibition of this enzyme. Using a bio-guided isolation strategy, linoleic acid ethyl ester has been identified as the compound responsible for this inhibition. Three other molecules - the alkaloid hippadine, the glycosylated benzyl alcohol derivative calleryanin and 4'-hydroxy-7-methoxyflavan - were also isolated and characterized for the first time from Crinum x powellii. The structures of these compounds were elucidated by spectrometric methods including EI, D/CI mass spectrometry, H-1, C-13 and 2D NMR experiments. Linoleic acid was also found to inhibit AChE.

Eight furanocoumarins, one coumarin and four acridone derivatives have been identified in the roots of Thamnosma rhodesica (Rutaceae). Rhodesiacridone, one of these acridone derivatives, is reported here for the first time. Its structure was elucidated by spectrometric methods including ESI-HR, EI, DCI mass spectrometry, H-1, C-13 and 2D NMR experiments. This novel compound showed activities against the intracellular form of a human pathogen, the protozoan parasite Leishmania major. Two known acridone related compounds, gravacridonediol and 1-hydroxy-10-methylacridone, exhibited activities against the intracellular form of the same parasite and the fungus Cladosporium cucumerinum, respectively. (C) 2004 Elsevier Ltd. All rights reserved.

Five isopimarane diterpenes (7beta-hydroxyisopimara-8,15-dien-14-one, 14alpha-hydroxyisopimara-7,15-dien-1-one, 1beta, 14alpha-dihydroxyisopimara-7,15-diene, 7beta-hydroxyisopimara-8(14),15-dien-1-one and 7beta-acetoxyisopimara-8(14),15-dien-1-one) have been isolated from the leaves of Hypoestes serpens (Acanthaceae). All compounds exhibited antifungal activity against both the plant pathogenic fungus Cladosporium cucumerinum and the yeast Candida albicans; two of them also displayed an acetylcholinesterase inhibition. The structures of the Compounds were determined by means of spectrometric methods, including 1D and 2D NMR experiments and MS analysis. (C) 2003 Published by Elsevier Ltd.

Investigation of the methanol extract of the roots of Gnidia involucrata (Thymelaeaceae) led to the isolation and characterization of two new 3,8"-biflavonoid diastereoisomers, named GB-4 (6a) and GB-4a (6b). Their absolute configurations were determined in mixture by on-line LC/CD measurements, which also allowed the revision of absolute configurations of the billavanoids GB-1 and GB-2, and the configurational assignment of GB-3.

A new triterpenoid saponin was isolated from the roots of Silene cucubalus and its structure was determined on the basis of one- and two-dimensional NMR spectroscopy as gypsogenin 3-O-beta-xylopyranosyl-(1-->3)-[beta-galactopyranosyl-(1-->2)]-beta-glucuronopyranoside. A known saponin, quillaic acid 3-O-beta-xylopyranosyl-(1-->3)-[beta-galactopyranosyl-(1-->2)]-beta-glucuronopyranoside, was also isolated.

LC-UV-MS analysis of the methanol extract of Jamesbrittenia fodina O. M. Hilliard (Scrophulariaceae) revealed the presence of cinnamic ester derivatives. Two isomeric pairs of these constituents were detected, but could not be isolated. In order to identify these unstable compounds, LC-H-1-NMR spectra were obtained for each individual isomer and standard NMR measurements were performed in-mixture. The spectra clearly demonstrated that the fractions consisted of mixtures of cis and trans cinnamoyl catalpol glycoside esters.

In comparison with other medicinal plants, the history of use of Echinacea is relatively short. The plant originates from North America and was employed by the indigenous Indians. The first archaeological evidence dates from the 18th century. Included in the name Echinacea or purple coneflower are several species of the Asteraceae family: Echinacea purpurea (L.) Moench, Echinacea angustifolia DC. and Echinacea pallida (Nutt.) Nutt. Information about the use of the plant from traditional healers ranges from external application for wounds, burns and insect bites to the chewing of roots for toothache and throat infections, and internal application for pain, coughs, stomach cramps and snake bites. The interest of white settlers was also drawn to this medicinal plant. The first Echinacea preparation, known as Meyers Blood Purifier, arrived on the market around 1880, with rheumatism, neuralgia and rattlesnake bites as indications. At the beginning of the 20th century, Echinacea was the most frequently used plant preparation in the USA. Commercial cultivation was started in Germany around 1939. The introduction and cultivation of Echinacea in Switzerland by A. Vogel was around 1950. Chemists and pharmacologists became interested in Echinacea and many constituents are now known, such as polysaccharides, echinacoside, cichoric acid, ketoalkenes and alkylamides. The extracts exhibit immunostimulant properties and are mainly used in the prophylaxis and therapy of colds, flu and septic complaints. Although there are over 400 publications concerning the plant and dozens of preparations of Echinacea n the market, the true identity of the active principles still remains open.

Over the last 10 years, numerous cases of intoxications, leading for the most part to end-stage renal failure, have been reported after consumption of slimming regimens made of Chinese herbal preparations. These intoxications were associated with species of the Aristolochia genus, such as Aristolochiafangchi (Aristolochiaceae), known to contain very nephrotoxic and carcinogenic metabolites named aristolochic acids. Several commercial dietary supplements, teas and phytomedicines used as slimming regimens were analysed for their aristolochic acid I content. A preliminary detection of this toxic compound was made by thin-layer chromatography. The presence of aristolochic acid I in these preparations was confirmed by a HPLC/UV-DAD/MS analysis. A quantitative determination of aristolochic acid I was also achieved in the incriminated preparations using both UV and MS detection. Out of 42 analysed preparations, four were found to contain aristolochic acid I and two were suspected to contain aristolochic acid derivatives. Immediate removal of these products from the Swiss market was called for. (C) 2003 Elsevier Science Ltd. All rights reserved.

A total of 148 crude ethanol extracts from 115 plant species were tested in vitro against Gram-negative strains (Escherichia coli, Pseudomonas aeruginosa) and the Gram-positive Staphylococcus aureus and Enterococcus faecalis. Moreover, they were submitted to antifungal assays against Candida albicans and Cladosporium cucumerinum, a human and a plant pathogenic microorganism, respectively, known to be good indicators of antifungal activity. No activity was detected against the Gram-negative bacteria, while 14.8% and 10.8% of the extracts showed Gram-positive bactericidal or bacteriostatic effects on S. aureus and E. faecalis, respectively. An antifungal activity was observed with 15 extracts (10.1%). Two species were particularly active against the fungi: Dioscorea minutiflora and Erythrina vogelii. The young tubers of D. minutiflora contain metabolites with a specific effect on fungi and were not active against the bacteria. On the other hand, E. vogelii was highly effective against the Gram-positive bacteria and the fungi.

Four new prenylated isoflavonoids, vogelins D-G (1-4), were isolated from the CH2Cl2 extract of Erythrina vogelii root bark in addition to the known compounds isolupalbigenin (5), ficuisoflavone (6), ulexone (7), isochandalon (8), and isoderrone (9). The structures 1-4 were elucidated by spectroscopic and chemical methods. The absolute configuration of compound 1 was determined on the basis of its CD spectrum. Possible biogenetic relationships among the E. vogelii isoflavonoids are briefly discussed.

Polygonum cuspidatum Sieb. and Zucc. has been traditionally used as a member of many anti-inflammatory polyherbal formulations, but is now a widespread invasive neophyte in Europe and America. To discuss if the invasive variety is chemically identical to the native one in traditional medicine, the different constituents of the invasive variety compared to the native variety were isolated and their anti-inflammatory activity was tested. Resveratroloside and catechin-(4α→8)-catechin, the newly found constituents in the invasive variety, have similar nitric oxide (NO) inhibition potency as that of piceid (the major constituent of P. cuspidatum), but the newly found major constituent, i.e., piceatannol glucoside, showed no apparent effect. On the other hand, as a marker, the total content of resveratrol in the methanol root extract after glucosidase hydrolysis was measured and compared between the invasive and native varieties. The total content of resveratrol measured in the root extracts of the Swiss sample was about 2.5 times less than that of the Chinese one. This study brings attention to the point that when the invasive variety of P. cuspidatum is used in traditional medicine, the chemical difference should be kept in mind.

Plants of the genus Garcinia (Clusiaceae) are traditionally used to relieve stomachaches, toothaches, and as a chew stick.In order to determine which compounds were responsible for these activities, a phytochemical investigation of the fruits and leaves of Garcinia preussii Engl. was pursued.Plants were extracted by solvents of various polarities. Compounds isolation was then carried out using chromatography methods (medium- and high-pressure liquid chromatography, open column and thin-layer chromatography). The isolated compounds were identified and characterized by using 1D and 2D NMR spectroscopies. The antioxidant activity was evaluated using DPPH(•), ABTS(•-), ALP, and ORAC assays. The antimicrobial activity was assayed against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Enterococcus faecalis by determining the minimum inhibitory concentration (MIC) value. The cytotoxic activity of most of the isolated compounds was evaluated on a small panel of human cancer cell lines (DU145, HeLa, HT-29, and A431) using the XTT method.The phytochemical investigation of G. preussii led to the isolation of eight known compounds, six benzophenones and two flavonoids. These compounds were tested for their biological activities. 1, 2, 3, 4, 7 and 8 demonstrated a high free radical scavenging activity with ER50 ranging from 0.1 to 0.7. The antimicrobial activity was shown only against Gram-positive bacteria for 1, 4, and 5. A moderate cytotoxic activity with IC50 ranging from 7 to 50 µM was observed, except for 6 which was not active.These results appear to support some of the properties reported for Garcinia species.

The stem bark CH2Cl2 extract of Ravensara crassifolia showed antifungal activity against the phytopathogenic fungus Cladosporium cucumerinum in a bioautographic TLC assay. Activity-guided fractionation afforded two new alpha -pyrones : (6S)-5,6-dihydro-6-[(2R)-2-hydroxy-6-phenylhexyl]-2H-pyran-2-one (1) and (6R)-6-[(4R,6R)-4,6-dihydroxy-10-phenyldec-1-enyl]-5,6-dihydro-2H-pyran-2-one (2). Their structures and absolute configurations were established by NMR spectroscopy, chemical methods, and CD spectroscopy. The antifungal activity against C. cucumerinum was determined for both compounds.

The terpenoid constituents of Targionia lorbeeriana grown in vivo and in vitro were com pared. The analysis of the dichloromethane extract was performed by HPLC-UV and by HPLC-M S. The obtained results revealed that the sesquiterpene lactones isolated from the dichloromethane extract of the wild Targionia lorbeeriana were also produced by the liverwort in in vitro cultures, in the same relative amounts. The composition of essential oils was evaluated by GC and GC-MS. Both, the yield and diversity of the essential oil obtained from wild growing T. lorbeeriana gametophytes were higher than those growing in vitro. Although, a significant number of compounds produced in vivo were maintained in vitro, a considerable number of other ones were not detected. Instead, under in vitro conditions, some new compounds were found which do not accumulate under wild conditions.

A total of 78 different extracts from 20 medicinal plants belonging to 14 plant families from Mali were tested for their antifungal, larvicidal, molluscicidal, antioxidant and radical scavenging activities. Dichloromethane, methanol, water and ethanol extracts were used. TLC autobiography for antifungal activity was run with Cladosporium cucumerinum and Candida albicans. Extracts were also tested on the larvae of the mosquitoes Aedes aegypti, Anopheles gambiae and Culex quinquefasciatus. Molluscicidal activities were established with the snails Biomphalaria glabrata, Biomphalaria pfeifferi and Bulinus truncatus. beta-Carotene and DPPH solutions sprayed on TLC plates were used for antioxidant and radical scavenging assays. Of the extracts investigated, 20% were antioxidant and radical scavengers, 19% fungicidal, 30% were larvicidal and 11% were molluscicidal. Three of the plant extracts, from Cussonia barteri (Araliaceae), Glinus oppositifolius (Aizoaceae) and Lannea velutina (Anacardiaceae) gave positive responses in all four tests.

Besides the known compounds longistylines C (1), D (2), and 3,5-dimethoxystilbene (5), five new prenylated stilbenes, named chiricanines A--E (3, 4, 6--8), have been isolated from the root bark of Lonchocarpus chiricanus. Their structures were resolved on the basis of spectrometric methods including (1)H, (13)C, and 2D NMR experiments and mass spectrometry. Compound 3 was the only prenylated stilbene to demonstrate antifungal effects against Cladosporium cucumerinum. Four of the isolated compounds showed toxic properties against larvae of the yellow fever-transmitting mosquito Aedes aegypti. Compound 5 was found to be as potent as rotenone in larvicidal dilution tests.

Two new 'quinone methide' diterpenes with a cassane skeleton were isolated from the root bark of Bobgunnia madagascariensis (DESV.) J.K. KIRKBR. & WIERSEMA (Leguminosae). The two compounds occurred as a diastereoisomer mixture 1/2, Their structure was established as (4R,6aS,10aS)- and (4S,6aS,10aS)-1,4,6a,7,8,9,10,10a-octahydro-4,11-dihydroxy-7,7,10a-trimethyl-2H-phenanthro[1,2-c]pyran-6,12-dione by spectroscopic methods and by comparison with the data obtained for another 'quinone methide' diterpene isolated previously from the same plant and identified by single-crystal X-ray analysis. H-1- and C-13-NMR signals were assigned by extensive in-mixture 2D correlation experiments, and H-1-NMR spectra of the separated diastereoisomers 1 and 2 were recorded by on-now LC/NMR. The interconversion of 1 and 2 was followed by repeated stop-flow LC/NMR experiments over a two-hour period, Compounds 1 and 2 showed moderate antifungal properties towards human pathogenic fungi, in particular the yeast Candida albicans.

For many social and environmental reasons, over the last few decades, there has been an increase in chronic and life-threatening diseases including mycoses, hyperuricemia-related disorders and some mental illnesses such as depression, anxiety and Parkinson's disease. In order to fight these diseases, compounds acting on various biological targets, including enzymes such as xanthine oxidase or monoamine oxidase, have to be screened. The enzyme xanthine oxidase catalyses the oxidation of hypoxanthine to xanthine and then to uric acid, which plays a crucial role in hyperuricemiarelated disorders such as gout and renal stones. One of the therapeutic approaches to treat these diseases is the use of xanthine oxidase inhibitors that block the production of uric acid. Monoamine oxidases (E.C.1.4.3.4) A and B catalyse the oxidative deamination of monoamines in the central nervous system and peripheral tissues. Inhibitors of MAO A are clinically useful to treat anxiety and depression since they are expected to increase both noradrenalin and serotonin levels in the brain. On the other hand, inhibition of MAO B appears to be an effective approach for the prevention and adjunct treatment of Parkinson's disease. In traditional Chinese medical practice, many medicinal herbs have been used to treat chronic diseases such as fungal infections, hyperuricemia-based disorders and mental illnesses. This usage is indicative for the presumable presence of antifungal phytochemicals and inhibitors of xanthine and monoamine oxidases. Plants do not represent the only source for interesting natural products; some endophytes ('special' microorganisms living inside the healthy host plant) are also known to produce secondary metabolites of promising pharmaceutical and/or agricultural potential. The above observations prompted us to search for natural antifungal compounds and inhibitors of xanthine and monoamine oxidases in different Chinese plants and endophyte cultures. The active constituents isolated were mainly mono-, sesqui-, di-, and triterpenes, sterols, coumarins, flavonoids, phenylethanoids, stilbenoids, alkaloids and alcohols.

African plants have long been the source of important products with nutritional and therapeutical value. Coffee originates from Ethiopia, Strophanthus species are strong arrow poisons and supply cardenolides for use against cardiac insufficiency, the Catharanthus roseus alkaloids are well-known antileukaemic agents - just to mention a few examples. Research is continuing on the vegetable material from this continent in an endeavour to find new compounds of therapeutic interest. An outline is presented here covering the results obtained by the Institute of Pharmacognosy and Phytochemistry of the University of Lausanne during 15 years' work on African plants. The strategy employed for the study of these plants is outlined, covering all aspects from the selection of plant material to the isolation of pure natural products. Different bioactivities have been investigated: the search for new antifungal, molluscicidal and larvicidal agents has been the most important axis. Results are also included for antibacterial, cytotoxicity, anti-inflammatory testing

Two new cyclobutane-type lignans, named moslolignans A and B, together with two known ones, andamanicin and magnosalin, were isolated from the whole plant of Mosla scabra. Their structures were established as 1 beta*,2 beta*,3 alpha*,4 alpha*-l,2-dimethyl-3-(3- methoxy-4,5-methylene-dioxyphenyl)-4-(2,4,5-trimethoxyphenyl)-cyclobutane and 1 beta*,2 beta*,3 alpha*,4 alpha"-1,2-dimethyl-3-(2,5-dimethoxy-3,4-methylenedioxyphenyl)-4-(2,4, 5-trimethoxyphenyl)-cyclobutane by spectroscopic methods. This is the first report of naturally-occurring cyclobutane-type lignans with asymmetrical substitutions. (C) 2000 Elsevier Science Ltd. All rights reserved.

Ginkgolic acids (GAs) are toxic phenolic compounds present in the fruits and leaves of Ginkgo biloba L. (Ginkgoacae). Their maximum level in phytopharmaceuticals containing ginkgo extracts has been recently restricted to 5 microg/g by the Commission E of the former Federal German Health Authority. In order to detect ginkgolic acids at these low levels, a sensitive and selective analytical method, based on liquid chromatography-electrospray mass spectrometry (LC-ES-MS) has been developed. The three main phenolic acids (1-3) of the chloroform fruit extract were isolated and used as standards for quantification. In the LC-ES-MS negative ion mode, calibration curves with good linearities (r=0.9973, n=6) were obtained in the range of 0.5-10 microg/g for compounds 1, 2 and between 0.1 and 7.5 microg/g (r=0.9949, n=6) for ginkgolic acid 3. The detection limits at a SIN ratio of 3 were 0.1 (3) and 0.25 microg/g (1, 2). Recoveries were around 101% at 5 microg/g for the substances detected in the leaf extracts. Good precision was achieved with relative standard deviations of less than 4% (n=6). The optimised method was applied to verify whether the amount of gingkolic acids was below 5 microg/g in a standardised leaf extract which is a constituent of a phytopreparation.

In addition to the known cordiaquinones A and B, two novel meroterpenoid naphthoquinones, named cordiaquinones J and K, have been isolated from the roots of Cordia curassavica. Their structures were elucidated by spectrometric methods including EI, D/CI mass spectrometry, 1H, 13C and 2D-NMR experiments. The four naphthoquinones demonstrated antifungal activities against Cladosporium cucumerinum, Candida albicans and toxic properties against larvae of the yellow fever-transmitting mosquito Aedes aegypti.

Purpose. Terminalia macropteraroots are used in Guinea-Bissau and other West African countries to treat infectious diseases like gonorrhoea. Previous work showed an ethanol extract of T. macroptera roots (T) to have an in vitro antimicrobial profile against Neisseria gonorrhoae (including resistant strains) and enteropathogenic agents. The most active fractions of this extract were identified as the diethyl ether (T2) and water (T5) fractions. The aim of the present study was the identification of major compounds present in T and simultaneously in T2 or T5.

A new phenolic glycoside, 1-(α- l -rhamnosyl(1-6)-β- d -glucopyranosyloxy)-3,4,5-trimethoxybenzene, together with the alkaloid N -( p -coumaroyl)-tryptamine and four known flavonoids were isolated from the methanolic bark extract of Ravensara anisata Danguy (Lauraceae). Their structures have been established by NMR spectroscopy, and chemical methods.

The leaves and bark dichloromethane extracts of Ravensara anisata showed antifungal activity against the yeast Candida albicans and the phytopathogenic fungus Cladosporium cucumerinum in bioautographic TLC assays. Activity-guided fractionation afforded two new α-pyrones: 6R∗-(4R∗-acetoxy-2S∗-hydroxy-8-phenyloctyl)-5,6-dihydro-2-H-pyran-2-one and 6R∗-(2S∗-acetoxy-4R∗-hydroxy-8-phenyloctyl)-5,6-dihydro-2-H-pyran-2-one. Their structures have been established by NMR spectroscopy, chemical methods and X-ray crystallographic analysis. The antifungal activity against C. albicans and C. cucumerinum was determined for both compounds.

A liquid chromatographic/mass spectrometric (MS) method involving electrospray ionization together with up-front collision-induced dissociation, tandem MS or MSn fragmentation has been developed for rapid on-line characterization of triterpene glycosides. Sensitive detection was obtained by post-column addition of alkaline buffer, providing intense deprotonated molecular ions. The experimental method has provided information on the sugar sequence and aglycone of each saponin within a crude plant extract. The method has been applied for the rapid estimation of saponin content in methanolic and aqueous extracts of dried berries of Phytolacca dodecandra (Phytolaccaceae). Copyright © 1999 John Wiley & Sons, Ltd.

Three new phenolic glycosides named eriosemasides A–C, one novel (named eriosematin F) and four known phenolic constituents were isolated from the n -BuOH-soluble fraction of the roots of Eriosema tuberosum . Their structures were established by spectroscopic analyses and chemical methods. All the phenolic compounds were fungitoxic except the phenolic glycosides.

Eight xanthones and a biphenyl have been isolated from the dichloromethane extract ofKielmeyera coriacea (Guttiferae) stem bark by a combination of centrifugal partition chromatography and gel filtration on Sephadex LH-20, with HPLC-UV monitoring of fractions. The structures of the isolated compounds (Figure 1) were established by spectroscopic methods (UV, EI-MS, D/CI-MS,1H NMR,13C NMR).

Three new sesquiterpene lactones (acetyltrifloculoside, 8,15- acetylsalonitenolide and 8-acetylsalonitenolide) and two known sesquiterpene lactones were isolated from a dichloromethane extract of the Portuguese liverwort Targionia lorbeeriana. Their structures were established by spectroscopic methods (EI and D/CI mass spectroscopy, 1H and 13C NMR) and that of acetyltrifloculoside was confirmed by X-ray crystallography. The three isolated guaianolide sesquiterpene lactones presented antifungal activity against Cladosporium cucumerinum and larvicidal activity against Aedes aegypti. Only one of the isolated lactones presented activity against Candida albicans.

A total of 204 crude extracts of Indonesian plants (77 species from 43 families) have been screened for their fungicidal (Cladosporium cucumerinum, Candida albicans) and free radical scavenging [2,2-diphenyl-1-picrylhydrazyl (DPPH) radical] activities. Of the species investigated, 20 were active against Cladosporium cucumerinum, nine against Candida albicans and 24 exhibited radical scavenging properties.