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ABSTRACT: The Lippia genus is used in ethnobotany as food, beverages, seasoning and antiseptic remedies, among others. The chemical compositions of fifteen extracts of six Lippia species were investigated comparatively by HPLC-PDA. To avoid data replication of previous works on this genus, Lippia lupulina Cham. root ethanol extract was selected for isolation procedures based on Principal Component Analyses (PCA) of such data. Seven compounds previously unreported in this genus were isolated from this extract (a triterpene, two furanonaphtoquinones, a furanochromone, an isoflavone, a stilbene and an iridoid). The activities of extracts, fractions and pure compounds towards Candida albicans, Candida krusei, Candida parapsilosis and Cryptococcus neoformans were investigated. Two fractions from the extract of Lippia salviaefolia leaves showed marked inhibition of fungal growth, in addition to verbascoside and asebogenin, which showed MICs lower than 15.6μg/ml and may be promising leads for the development of new antifungal agents, especially against C. neoformans.
Food Chemistry 12/2012; 135(3):2086-94. · 3.65 Impact Factor
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ABSTRACT: As a part of our ongoing research for bioactive compounds from Turkish Astragalus species, the investigation of Astragalus tauricolus has been carried out. An approach based on HPLC-ESIMS(n) experiments has been used to profile the triterpene glycosides occurring in the butanol extract of the whole plant. On the basis of the results of the online screening by HPLC-ESIMS(n), 22 oleanane-type triterpene glycosides, including ten compounds never reported before, were isolated, and their structures were established by the extensive use of 1D and 2D-NMR experiments along with ESIMS and HRMS analysis. Noteworthy, cycloartane-type triterpene glycosides, the main constituents of Astragalus spp., were not found. This peculiar feature characterizes a very limited group of Astragalus spp. The antiproliferative activity of the isolated compounds 1-12, 15, 17-19 was evaluated against a small panel of cancer cell lines. Only compound 11 showed an IC(50) of 22μM against human leukemia cell line (U937). The other tested compounds, in a range of concentrations between 1 and 50μM, did not cause any significant reduction of the cell number.
Phytochemistry 10/2012; · 3.35 Impact Factor
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ABSTRACT: The methanol extract of the flowers of Paepalanthus geniculatus Kunth. showed radical-scavenging activity in the TEAC assay. An analytical approach based on HPLC-ESIMS(n) was applied to obtain the metabolite profile of this extract and led to the rapid identification of 19 polyphenolic compounds comprising flavonoids and naphthopyranones. The new naphthopyranone (10, 16), quercetagetin (1, 5, 7, 13), and galetine derivatives (9, 11, 17, 19), and a flavonol glucoside cyclodimer in the truxillate form (12), were identified. Compounds 2, 6, and 7 showed the highest antioxidant capacity and ability to affect the levels of intracellular ROS in human prostate cancer cells (PC3).
Journal of Natural Products 04/2012; 75(4):547-56. · 3.13 Impact Factor
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ABSTRACT: Nine furostanol glycosides, namely caucasicosides E-M, were isolated from the MeOH extract of the leaves of Helleborus caucasicus, along with 11 known compounds including nine furostanol glycosides, a bufadienolide and an ecdysteroid. Their structures were established by the extensive use of 1D and 2D NMR experiments along with ESIMS(n) analyses. The steroidal composition of leaves of H. caucasicus shows as particular feature the occurrence of steroidal compounds belonging to the 5β series, unusual for Helleborus species, and in particular, caucasicosides F-H are based on a 5β-polyhydroxylated steroidal aglycon never reported before.
Phytochemistry 09/2011; 72(17):2180-8. · 3.35 Impact Factor
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Cristiano Soleo Funari,
Thais Gaban Passalacqua,
Daniel Rinaldo, Assunta Napolitano,
Michela Festa,
Anna Capasso,
Sonia Piacente,
Cosimo Pizza,
Maria Claudia Marx Young,
Giselda Durigan,
Dulce Helena Siqueira Silva
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ABSTRACT: Four interconverting flavanone glycosides [(2R)- and (2S)-3',4',5,6-tetrahydroxyflavanone 7-O-β-D-glucopyranoside, and (2R)- and (2S)-3',4',5,8-tetrahydroxyflavanone 7-O-β-D-glucopyranoside], in addition to eight known flavonoids [naringenin, asebogenin, sakuranetin, 6-hydroxyluteolin 7-O-β-D-glucoside, (2R)- and (2S)-eriodictyol 7-O-β-D-glucopyranoside, aromadendrin and phloretin], three phenylpropanoid glycosides [forsythoside B, alyssonoside and verbascoside] and the epoxylignan lariciresinol 4'-O-β-D-glucopyranoside were isolated and identified in the EtOH extract of the aerial parts of Lippia salviaefolia Cham. The phytochemical study herein was guided by preliminary antioxidant tests, namely, β-carotene protection and 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical scavenging activity. The crude extracts, their active fractions and the isolated compounds were assayed against intracellular reactive oxygen species (ROS) and human embryonic kidney HEK-293 and human melanoma M14 cancer cell growth. Aromadendrin and phloretin were able to counteract elevation of ROS induced by the oxidant t-butylhydroperoxide (t-BOOH) in HEK-293 cells, whereas phloretin strongly protected HEK-293 cells from ROS damage at 1 μM. Additionally, phloretin exhibited a significant growth inhibitory effect at 20-40 μM in both HEK-293 and M14 cells and induced a concentration dependent apoptosis at 20 μM in M14 cells, suggesting a selective action towards malignant cells. Due to their equilibria, the four interconverting flavanone glycosides were studied using 1D and 2D NMR, HPLC-CD-PDA and HRMS analyses.
Phytochemistry 08/2011; 72(16):2052-61. · 3.35 Impact Factor
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ABSTRACT: A comparative metabolite profiling of the underground parts and leaves of Ruscus ponticus was obtained by an HPLC-ESIMS(n) method, based on high-performance liquid chromatography coupled to electrospray positive ionization multistage ion trap mass spectrometry. The careful study of HPLC-ESIMS(n) fragmentation pattern of each chromatographic peak, in particular the identification of diagnostic product ions, allowed us to get a rapid screening of saponins belonging to different classes, such as dehydrated/or not furostanol, spirostanol and pregnane glycosides, and to promptly highlight similarities and differences between the two plant parts. This approach, followed by isolation and structure elucidation by 1D- and 2D-NMR experiments, led to the identification of eleven saponins from the underground parts, of which two dehydrated furostanol glycosides and one new vespertilin derivative, and nine saponins from R. ponticus leaves, never reported previously. The achieved results highlighted a clean prevalence of furostanol glycoside derivatives in R. ponticus leaves rather in the underground parts of the plant, which showed a wider structure variety. In particular, the occurrence of dehydrated furostanol derivatives, for the first time isolated from a Ruscus species, is an unusual finding which makes unique the saponins profile of R. ponticus.
Phytochemistry 02/2011; 72(7):651-61. · 3.35 Impact Factor
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ABSTRACT: Ceramides and cerebrosides are key compounds in the metabolism of sphingolipids. Produced in response to a variety of apoptotic stimuli, these metabolites mediate either mitogenic or apoptotic responses, depending on cell type and nature of stimulus. Novel strategies using these selective targets for a therapeutic intervention, e.g. in cancer, cardiovascular and neurodegenerative diseases, and HIV, have been developed, along with anticancer approaches using controlled delivery of exogenous natural ceramides from ceramide-based liposomes. Thus, great is the need to find selective and sensitive analytical methods allowing a prompt detection of ceramides and cerebrosides in natural matrices. Here we report an analytical study carried out on the Amazonian plant Dracontium loretense, resulted in a preliminary analysis a rich source of this class of natural compounds. A handy, selective, and sensitive methodology based on high-performance liquid chromatography coupled to electrospray negative ionization multistage ion trap mass spectrometry (HPLC-ESI/ITMS(n)) was developed. Analysis of fingerprint multistage mass spectra allowed the rapid identification of 3 major long-chain bases and their exact pairing with 11 different fatty acids and with carbohydrate headgroups. Thus, the structures of 21 ceramide and cerebroside species, among which 7 molecules never reported before, were unambiguously assigned. Results obtained in this study demonstrated that this analytical approach could provide a reliable and sensitive method to obtain the qualitative on-line profiling of ceramides and cerebrosides in new medicinal plant matrices.
Journal of pharmaceutical and biomedical analysis 01/2011; 55(1):23-30. · 2.45 Impact Factor
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ABSTRACT: The species Astronium urundeuva (Allemao) Engl. and Astronium graveolens Jacq., which are used in Brazilian folk medicine to treat allergies, inflammation, diarrhea and ulcers, were investigated for their composition. The aim of this study was to define a rapid and reliable analytical approach, based on the flow-injection analysis-electrospray ionization-ion trap-tandem mass spectrometry (FIA-ESI-IT-MS-MS) and matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-ToF-MS), to investigate the full range of hydrolyzable tannins present in the extracts of these Astronium species. The MALDI-ToF-MS analysis allowed us to ascertain the presence of hydrolysable tannins in both Astronium species as a series of gallotannins with degrees of polymerization of 7 to 13 galloyl units. Moreover, the analysis by FIA-ESI-IT-MS-MS, as well as confirming this result and chemically defining gallotannins as galloylglucose compounds, highlighted the presence of further classes of hydrolysable tannins, such as hexahydrodiphenoyl esters of glucose and some gallic acid derivatives, providing information about their structure by a careful study of their fragmentation patterns. Finally, the evaluation of the number of positional isomers of gallotannins occurring in both Astronium species was obtained by high-performance liquid chromatography-electrospray ionization-ion trap mass spectrometry (HPLC/ESI-IT-MS). This is the first mass spectrometric evidence relating to the existence of gallotannins in Astronium genus.
European Journal of Mass Spectrometry 01/2011; 17(4):365-75. · 1.21 Impact Factor
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ABSTRACT: Liquid chromatography-electrospray ionization multistage ion trap mass spectrometry (LC-ESI-IT-MS(n)) was used to analyze the secondary metabolites in the methanol extract of the capitulae of Eriocaulon ligulatum. The major components were mono- and diglycosides of flavonoids and naphthopyranones. Eleven compounds, including four new flavonol glycosides, were identified based on their fragmentation patterns in MS experiments and on NMR analysis of the isolated compounds. The described data may contribute to a better understanding of the taxonomic classification of the Eriocaulaceae family.
Natural product communications 12/2009; 4(12):1651-6. · 1.24 Impact Factor
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ABSTRACT: An HPLC-ESIMS(n) method, based on high-performance liquid chromatography coupled to electrospray positive ionisation multistage ion trap mass spectrometry, has been used as an effective tool to rapidly identify and guide the isolation of target saponins from the ethanol extract of the leaves of Ruscus colchicus Y. Yeo. Twenty-two steroidal glycosides, including seventeen furostanol, four spirostanol and one cholestane glycosides, were online identified. Subsequently, compounds were isolated and their structures were established by the extensive use of 1D- and 2D-NMR experiments. The structures identified by MS were fully consistent with those elucidated by NMR data. Sixteen steroidal glycosides, including thirteen furostanol, two spirostanol and one cholestane glycosides, were identified along with four known furostanol and two spirostanol glycosides. The saponin profile shows that the furostanol glycosides are the main constituents of R. colchicus extract, unlike the other Ruscus species, for which the spirostanol derivatives generally are reported as the major compounds. Moreover, for the first time a cholestane glycoside has been isolated from R. colchicus.
Phytochemistry 09/2009; 70(17-18):2078-88. · 3.35 Impact Factor
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ABSTRACT: Four novel oxylipins (1-4) were isolated from the n-butanol extract of the corms of Dracontium loretense. Their structures were assigned by 1D and 2D NMR analyses and electrospray ionization multistage ion trap mass spectrometry (ESI-ITMS(n)) data. Relative configurations were assigned on the basis of combined analysis of homonuclear and heteronuclear (2,3)J couplings, along with ROE data. Oxylipin 2 exhibited an immunostimulatory effect on human PBMC proliferation.
Journal of Natural Products 05/2009; 72(5):813-7. · 3.13 Impact Factor
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ABSTRACT: Sixteen novel and ten known galactolipids have been isolated and characterized from the leaves of Ipomoea batatas L. (sweet potato) using an analytical method based on high-performance liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight tandem mass spectrometry. Using this technique, the structures and regiochemistries of the fatty acyl groups and the positions of the double bonds on the acyl chains were determined. Sugar moieties were identified by analysis of one- and two-dimensional nuclear magnetic resonance spectra. The positions of the double bonds of polyunsaturated fatty acids were confirmed, and in some cases their geometries determined, by gas chromatography-mass spectrometry. This is the first report of galactolipids in the leaves of sweet potato.
Journal of Agricultural and Food Chemistry 01/2008; 55(25):10289-97. · 2.82 Impact Factor
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ABSTRACT: Several marine terpenoids that contain at least one reactive aldehyde group, such as manoalide and its congeners, possess interesting anti-inflammatory activities that are mediated by the covalent inactivation of secretory phospholipase A(2) (sPLA(2)). Scalaradial, a 1,4-dialdehyde marine terpenoid that was isolated from the sponge Cacospongia mollior, is endowed with a relevant anti-inflammatory profile, both in vitro and in vivo, through selective sPLA(2) inhibition. Due to its peculiar dialdehyde structural feature, it has been proposed that scalaradial exerts its enzymatic inactivation by means of an irreversible covalent modification of its target. In the context of our on-going research on anti-PLA(2) natural products and their interaction at a molecular level, we studied scalaradial in an attempt to shed more light on the molecular mechanism of its PLA(2) inhibition. A detailed analysis of the reaction profile between scalaradial and bee venom PLA(2), a model sPLA(2) that shares a high structural homology with the human synovial enzyme, was performed by a combination of spectroscopic techniques, chemical reactions (selective modifications, biomimetic reactions), and classical protein chemistry (such as proteolytic digestion, HPLC and mass spectrometry), along with molecular modeling studies. Unexpectedly, our data clearly indicated the noncovalent forces to be the leading event in the PLA(2) inactivation process; thus, the covalent modification of the enzyme emerges as only a minor side event in the ligand-enzyme interaction. The overall picture might be useful in the design of SLD analogues as new potential anti-inflammatory compounds that target sPLA(2) enzymes.
ChemBioChem 10/2007; 8(13):1585-91. · 3.94 Impact Factor
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ABSTRACT: A rapid analytical approach suitable to achieve a comprehensive characterization of the compounds present in the infusion prepared from the leaves of Byrsonima fagifolia Niedenzu (Malpighiaceae), a Brazilian plant used as an infusion to treat gastric disorders, was developed. The method was based on high-performance liquid chromatography coupled to electrospray negative ionisation multistage ion trap mass spectrometry (HPLC/ESI-ITMSn). The main ions in the ESI-ITMS spectra were attributed to a quinic acid core containing from one to five galloyl units. Quercetin derivatives containing one and two sugar moieties as well as galloyl esterification were also detected. These results indicated that HPLC/ESI-ITMSn is easily applicable to infusions of this plant and allows the rapid and direct identification of these compounds in crude plant extracts.
Rapid Communications in Mass Spectrometry 02/2007; 21(8):1393-1400. · 2.79 Impact Factor
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ABSTRACT: The synthesis and biological activity of the marine cyclopeptide hymenamide C(1), showing an inhibitory effect on human neutrophil elastase degranulation release, were recently described. Based on this result, it was decided to undertake a systematic structure-activity relationship study of this cyclopeptide, based on the Ala-scan technique, in order to obtain useful information for the rational design of additional analogues. The synthesis and characterization of the seven Ala modified analogues are reported and their biological and pharmacological properties are described.
Journal of Peptide Science 09/2002; 8(8):407-17. · 1.80 Impact Factor
