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Sample records for monomeric 3-alkylpyridinium alkaloid

  1. Synthesis of marine-derived 3-alkylpyridinium alkaloids with potent antiprotozoal activity

    NARCIS (Netherlands)

    Rodenko, B.; Al-Salabi, M.I.; Teka, I.A.; Ho, W.; El-Sabbagh, N.; Ali, J.A.M.; Ibrahim, H.M.S.; Wanner, M.J.; Koomen, G.J.; de Koning, H.P.

    2011-01-01

    Given the pressing need for new antiprotozoal drugs without cross-resistance with current (failing) chemotherapy, we have explored 3-tridecylpyridinium alkaloids (3TPAs), derivatives of viscosamine, as antiparasitic agents. We have developed a simple synthetic route toward viscosamine and related cy

  2. Njaoaminiums A, B, and C: Cyclic 3-Alkylpyridinium Salts from the Marine Sponge Reniera sp.

    Directory of Open Access Journals (Sweden)

    Philippe Amade

    2009-11-01

    Full Text Available Three novel cyclic 3-alkylpyridinium salts, named njaoaminiums A, B, and C (1-3, were isolated from the marine sponge Reniera sp., collected off the coasts of Pemba Island, Tanzania. The structural determination of the compounds was based on 1D and 2D NMR studies and mass spectral determinations. Njaoaminiums B (2 and C (3 are the first examples of cyclic 3-alkylpyridinium salts bearing a methyl substituent on the alkyl chains. These compounds are assumed to be biosynthetic precursors of the njaoamines, previously isolated from the same sponge. The absolute configurations of the methyls of 2 and 3 were assigned by comparison between experimental and TDDFT calculated circular dichroism spectra on the most stable conformer. Compound 2 showed weak cytotoxicity against the three human tumor cell lines MDA-MB-231, A549, and HT29.

  3. Binding and permeabilization of lipid bilayers by natural and synthetic 3-alkylpyridinium polymers.

    Science.gov (United States)

    Grandič, Marjana; Zovko, Ana; Frangež, Robert; Turk, Tom; Sepčić, Kristina

    2012-03-01

    Naturally occurring 3-alkylpyridinium polymers from the marine sponge Reniera sarai are membrane-active compounds exerting a selective cytotoxicity towards non small cell lung cancer cells, and stable transfection of nucleated mammalian cells. In view of their possible use as chemotherapeutics and/or transfection tools, three poly-APS based synthetic compounds were tested on their activity using natural and artificial lipid membranes. The tested compounds were found to be very stable over a wide range of temperature, ionic strength, and pH, and to prefer the solid-ordered membrane state. Their membrane-damaging activity increases with the length of their alkyl chains and the degree of polymerization. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Stereospecific approach to the synthesis of ring-A oxygenated sarpagine indole alkaloids. Total synthesis of the dimeric indole alkaloid P-(+)-dispegatrine and six other monomeric indole alkaloids.

    Science.gov (United States)

    Edwankar, Chitra R; Edwankar, Rahul V; Namjoshi, Ojas A; Liao, Xuebin; Cook, James M

    2013-07-05

    The first regio- and stereocontrolled total synthesis of the bisphenolic, bisquaternary alkaloid (+)-dispegatrine (1) has been accomplished in an overall yield of 8.3% (12 reaction vessels) from 5-methoxy-d-tryptophan ethyl ester (17). A crucial late-stage thallium(III) mediated intermolecular oxidative dehydrodimerization was employed in the formation of the C9-C9' biaryl axis in 1. The complete stereocontrol observed in this key biaryl coupling step is due to the asymmetric induction by the natural sarpagine configuration of the monomer lochnerine (6) and was confirmed by both the Suzuki and the oxidative dehydrodimerization model studies on the tetrahydro β-carboline (35). The axial chirality of the lochnerine dimer (40) and in turn dispegatrine (1) was established by X-ray crystallography and was determined to be P(S). Additionally, the first total synthesis of the monomeric indole alkaloids (+)-spegatrine (2), (+)-10-methoxyvellosimine (5), (+)-lochnerine (6), lochvinerine (7), (+)-sarpagine (8), and (+)-lochneram (11) were also achieved via the common pentacyclic intermediate 16.

  5. Toxicity of the synthetic polymeric 3-alkylpyridinium salt (APS3) is due to specific block of nicotinic acetylcholine receptors.

    Science.gov (United States)

    Grandič, Marjana; Aráoz, Romulo; Molgó, Jordi; Turk, Tom; Sepčić, Kristina; Benoit, Evelyne; Frangež, Robert

    2013-01-01

    The in vivo and in vitro toxic effects of the synthetic polymeric 3-alkylpyridinium salt (APS3), from the Mediterranean marine sponge Reniera sarai, were evaluated on mammals, with emphasis to determine its mode of action. The median lethal doses of APS3 were 7.25 and higher that 20mg/kg in mouse and rat, respectively. Intravenous administration of 7.25 and 20mg/kg APS3 to rat caused a significant fall followed by an increase in mean arterial blood pressure accompanied by tachycardia. In addition, cumulative doses of APS3 (up to 60 mg/kg) inhibited rat nerve-evoked skeletal muscle contraction in vivo, with a median inhibitory dose (ID(50)) of 37.25mg/kg. When administrated locally by intramuscular injection to mouse, APS3 decreased the compound muscle action potential recorded in response to in vivo nerve stimulation, with an ID(50) of 0.5mg/kg. In vitro experiments confirmed the inhibitory effect of APS3 on mouse hemidiaphragm nerve-evoked muscle contraction with a median inhibitory concentration (IC(50)) of 20.3 μM, without affecting directly elicited muscle contraction. The compound inhibited also miniature endplate potentials and nerve-evoked endplate potentials with an IC(50) of 7.28 μM in mouse hemidiaphragm. Finally, APS3 efficiently blocked acetylcholine-activated membrane inward currents flowing through Torpedo nicotinic acetylcholine receptors (nAChRs) incorporated to Xenopus oocytes, with an IC(50) of 0.19 μM. In conclusion, our results strongly suggest that APS3 blocks muscle-type nAChRs, and show for the first time that in vivo toxicity of APS3 is likely to occur through an antagonist action of the compound on these receptors.

  6. Bromopyrrole Alkaloids from Okinawan Marine Sponges Agelas spp.

    Science.gov (United States)

    Tanaka, Naonobu; Kusama, Taishi; Kashiwada, Yoshiki; Kobayashi, Jun'ichi

    2016-01-01

    In our continuing study for structurally and biogenetically interesting natural products from marine organisms, Okinawan marine sponges Agelas spp. were investigated, resulting in the isolation of 18 unique alkaloids including five dimeric bromopyrrole alkaloids (1-5), ten monomeric bromopyrrole alkaloids (6-15), and three conjugates of monomeric bromopyrrole alkaloid and hydroxykynurenine (16-18). In this mini-review, the isolation, structure elucidation, and antimicrobial activities of these alkaloids are summarized.

  7. Vinca alkaloids.

    Science.gov (United States)

    Moudi, Maryam; Go, Rusea; Yien, Christina Yong Seok; Nazre, Mohd

    2013-11-01

    Vinca alkaloids are a subset of drugs obtained from the Madagascar periwinkle plant. They are naturally extracted from the pink periwinkle plant, Catharanthus roseus G. Don and have a hypoglycemic as well as cytotoxic effects. They have been used to treat diabetes, high blood pressure and have been used as disinfectants. The vinca alkaloids are also important for being cancer fighters. There are four major vinca alkaloids in clinical use: Vinblastine (VBL), vinorelbine (VRL), vincristine (VCR) and vindesine (VDS). VCR, VBL and VRL have been approved for use in the United States. Vinflunine is also a new synthetic vinca alkaloid, which has been approved in Europe for the treatment of second-line transitional cell carcinoma of the urothelium is being developed for other malignancies. Vinca alkaloids are the second-most-used class of cancer drugs and will stay among the original cancer therapies. Different researches and studies for new vinca alkaloid applications will be carried out in this regard.

  8. Pyrrolizidine alkaloids.

    Science.gov (United States)

    Robertson, Jeremy; Stevens, Kiri

    2014-12-01

    This review covers pyrrolizidine alkaloids isolated from natural sources. Topics include: aspects of structure, isolation, and biological/pharmacological studies; total syntheses of necic acids, necine bases and closely-related non-natural analogues.

  9. Vinca Alkaloids

    Directory of Open Access Journals (Sweden)

    Maryam Moudi

    2013-01-01

    Full Text Available Vinca alkaloids are a subset of drugs obtained from the Madagascar periwinkle plant. They are naturally extracted from the pink periwinkle plant, Catharanthus roseus G. Don and have a hypoglycemic as well as cytotoxic effects. They have been used to treat diabetes, high blood pressure and have been used as disinfectants. The vinca alkaloids are also important for being cancer fighters. There are four major vinca alkaloids in clinical use: Vinblastine (VBL, vinorelbine (VRL, vincristine (VCR and vindesine (VDS. VCR, VBL and VRL have been approved for use in the United States. Vinflunine is also a new synthetic vinca alkaloid, which has been approved in Europe for the treatment of second-line transitional cell carcinoma of the urothelium is being developed for other malignancies. Vinca alkaloids are the second-most-used class of cancer drugs and will stay among the original cancer therapies. Different researches and studies for new vinca alkaloid applications will be carried out in this regard.

  10. Alkaloids from Delphinium pentagynum.

    Science.gov (United States)

    Díaz, Jesús G; Ruiz, Juan García; Herz, Werner

    2004-07-01

    Aerial parts of a collection of Delphinium pentagynum Lam. from Niebla, Southern Spain, furnished one diterpene alkaloid, 2-dehydrodeacetylheterophylloidine, two norditerpene alkaloids, 14-demethyl-14-isobutyrylanhweidelphinine and 14-demethyl-14-acetylanhweidelphinine, the known alkaloids 14-deacetylnudicauline, methyllycaconitine, 14-deacetyl-14-isobutyrylnudicauline, 14-acetylbrowniine, browniine, delcosine, lycoctonine, 18-methoxygadesine, neoline, karakoline and the aporphine alkaloid magnoflorine. Structures of the alkaloids were established by MS, 1D and 2-D NMR techniques.

  11. Exploiting plant alkaloids.

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    Schläger, Sabrina; Dräger, Birgit

    2016-02-01

    Alkaloid-containing plants have been used for medicine since ancient times. Modern pharmaceuticals still rely on alkaloid extraction from plants, some of which grow slowly, are difficult to cultivate and produce low alkaloid yields. Microbial cells as alternative alkaloid production systems are emerging. Before industrial application of genetically engineered bacteria and yeasts, several steps have to be taken. Original alkaloid-forming enzymes have to be elucidated from plants. Their activity in the heterologous host cells, however, may be low. The exchange of individual plant enzymes for alternative catalysts with better performance and optimal fermentation parameters appear promising. The overall aim is enhancement and stabilization of alkaloid yields from microbes in order to replace the tedious extraction of low alkaloid concentrations from intact plants.

  12. Alkaloids in Marine Algae

    OpenAIRE

    Ekrem Sezik; Aline Percot; Kasım Cemal Güven

    2010-01-01

    This paper presents the alkaloids found in green, brown and red marine algae. Algal chemistry has interested many researchers in order to develop new drugs, as algae include compounds with functional groups which are characteristic from this particular source. Among these compounds, alkaloids present special interest because of their pharmacological activities. Alkaloid chemistry has been widely studied in terrestrial plants, but the number of studies in algae is insignificant. In this review...

  13. Ergot and Its Alkaloids

    National Research Council Canada - National Science Library

    Paul L Schiff Jr

    2006-01-01

      This manuscript reviews the history and pharmacognosy of ergot, and describes the isolation/preparation, chemistry, pharmacodynamics, and pharmacotherapeutics of the major ergot alkaloids and their derivatives...

  14. Alkaloids from Menispermum dauricum.

    Science.gov (United States)

    Yu, Bing-Wu; Chen, Jian-Yong; Wang, Yan-Ping; Cheng, Kin-Fin; Li, Xiao-Yu; Qin, Guo-Wei

    2002-10-01

    The alkaloids, dechloroacutumidine and 1-epidechloroacutumine, together with three known alkaloids, acutumidine, acutumine, and dechloroacutumine, were isolated from the rhizomes of Menispermum dauricum and their structures established by spectral and chemical methods. The cytotoxicity of each compound against the growth of human cell lines was studied, and acutumine selectively inhibited T-cell growth.

  15. [Alkaloids of Annonaceae. XXIX. Alkaloids of Annona muricata].

    Science.gov (United States)

    Leboeuf, M; Legueut, C; Cavé, A; Desconclois, J F; Forgacs, P; Jacquemin, H

    1981-05-01

    From leaves, root - and stem - barks of Annona muricata L., seven isoquinoline alkaloids have been isolated: reticuline (main alkaloid), coclaurine, coreximine, atherosperminine, stepharine. Anomurine and anomuricine, two minor alkaloids, are new tetrahydrobenzylisoquinolines, with 5, 6, 7 substituted ring A. The phytochemical significance of these alkaloids is discussed.

  16. Genotoxic effect of alkaloids

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    J. A. P. Henriques

    1991-01-01

    Full Text Available Because of the increase use of alkaloids in general medical practice in recent years, it is of interest to determine genotoxic, mutagenic and recombinogenic response to different groups of alkaloids in prokaryotic and eucaryotic organisms. Reserpine, boldine and chelerythrine did not show genotoxicity response in the SOS-Chromotest whereas skimmianine showed genotixicity in the presence of a metabolic activation mixture. Voacristine isolated fromthe leaves of Ervatamia coronaria shows in vivo cytostatic and mutagenic effects in Saccharomyces cerevisiae hapioids cells. The Rauwolfia alkaloid (reserpine was not able to induce reverse mutation and recombinational mitotic events (crossing-over and gene conversion in yeast diploid strain XS2316.

  17. Alkaloids of Ocotea brachybotra.

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    Vecchietti, V; Casagrande, C; Ferrari, G

    1977-11-01

    Aporphine, proaporphine and morphinane alkaloids were isolated from the leaves of a Brazilian Lauracea, Ocotea brachybotra (Meiss.) Mez. The known alkaloids were identified through their physico-chemical properties as: (I) (+/-)-glaziovine, (II) dicentrine, (III) ocopodine, (IV) cassynthicine, (V) predicentrine, (VI) leucoxine, (IX) sinacutine and (X) pallidine. The structure of (VI) leucoxine was confirmed by a detailed analysis of the N.M.R. spectra recorded in various conditions. New morphinane alkaloids, (XI) ocobotrine and (XII) 14-espisinomenine, having the unusual B/C-trans configuration were also isolated. Their structures were determined using spectroscopic methods and chemical correlations.

  18. Novel Euglenoid Derived Alkaloid

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Disclosed herein is a purified toxin isolated from Euglena sanguinea. More specifically the toxin, termed euglenophycin, is an alkaloid having herbicidal and...

  19. Occurrence of halogenated alkaloids.

    Science.gov (United States)

    Gribble, Gordon W

    2012-01-01

    Once considered to be isolation artifacts or chemical "mistakes" of nature, the number of naturally occurring organohalogen compounds has grown from a dozen in 1954 to >5000 today. Of these, at least 25% are halogenated alkaloids. This is not surprising since nitrogen-containing pyrroles, indoles, carbolines, tryptamines, tyrosines, and tyramines are excellent platforms for biohalogenation, particularly in the marine environment where both chloride and bromide are plentiful for biooxidation and subsequent incorporation into these electron-rich substrates. This review presents the occurrence of all halogenated alkaloids, with the exception of marine bromotyrosines where coverage begins where it left off in volume 61 of The Alkaloids. Whereas the biological activity of these extraordinary compounds is briefly cited for some examples, a future volume of The Alkaloids will present full coverage of this topic and will also include selected syntheses of halogenated alkaloids. Natural organohalogens of all types, especially marine and terrestrial halogenated alkaloids, comprise a rapidly expanding class of natural products, in many cases expressing powerful biological activity. This enormous proliferation has several origins: (1) a revitalization of natural product research in a search for new drugs, (2) improved compound characterization methods (multidimensional NMR, high-resolution mass spectrometry), (3) specific enzyme-based and other biological assays, (4) sophisticated collection methods (SCUBA and remote submersibles for deep ocean marine collections), (5) new separation and purification techniques (HPLC and countercurrent separation), (6) a greater appreciation of traditional folk medicine and ethobotany, and (7) marine bacteria and fungi as novel sources of natural products. Halogenated alkaloids are truly omnipresent in the environment. Indeed, one compound, Q1 (234), is ubiquitous in the marine food web and is found in the Inuit from their diet of whale

  20. Marine Indole Alkaloids

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    Natalie Netz

    2015-08-01

    Full Text Available Marine indole alkaloids comprise a large and steadily growing group of secondary metabolites. Their diverse biological activities make many compounds of this class attractive starting points for pharmaceutical development. Several marine-derived indoles were found to possess cytotoxic, antineoplastic, antibacterial and antimicrobial activities, in addition to the action on human enzymes and receptors. The newly isolated indole alkaloids of marine origin since the last comprehensive review in 2003 are reported, and biological aspects will be discussed.

  1. Analysis of Ergot Alkaloids

    OpenAIRE

    Colin Crews

    2015-01-01

    The principles and application of established and newer methods for the quantitative and semi-quantitative determination of ergot alkaloids in food, feed, plant materials and animal tissues are reviewed. The techniques of sampling, extraction, clean-up, detection, quantification and validation are described. The major procedures for ergot alkaloid analysis comprise liquid chromatography with tandem mass spectrometry (LC-MS/MS) and liquid chromatography with fluorescence detection (LC-FLD). Ot...

  2. Size separation of analytes using monomeric surfactants

    Science.gov (United States)

    Yeung, Edward S.; Wei, Wei

    2005-04-12

    A sieving medium for use in the separation of analytes in a sample containing at least one such analyte comprises a monomeric non-ionic surfactant of the of the general formula, B-A, wherein A is a hydrophilic moiety and B is a hydrophobic moiety, present in a solvent at a concentration forming a self-assembled micelle configuration under selected conditions and having an aggregation number providing an equivalent weight capable of effecting the size separation of the sample solution so as to resolve a target analyte(s) in a solution containing the same, the size separation taking place in a chromatography or electrophoresis separation system.

  3. Monomeric Friction Coefficient of Metalnanodispersible Polymeric Systems

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    B.B. Kolupayev

    2016-12-01

    Full Text Available Influence of a nanodispersible metal excipient in number of 0    5,0 vol.% Cu for the size of a monomeric friction coefficient of polyvinylchloride (PVC systems in temperature range 298  Т  (Tg + 10 K is investigated. It is shown that various types of coordination movements of building blocks are described by a friction coefficient which serves as a measure of influence of external fields and ingredients on viscoelastic behavior of a composite. The analysis of processes of a relaxation on the basis of the theory of flexible chains taking into account power and entropic factors is carried out.

  4. Alkaloids from Hippeastrum papilio

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    Jaume Bastida

    2011-08-01

    Full Text Available Galanthamine, an acetylcholinesterase inhibitor marketed as a hydrobromide salt (Razadyne®, Reminyl® for the treatment of Alzheimer’s disease (AD, is obtained from Amaryllidaceae plants, especially those belonging to the genera Leucojum, Narcissus, Lycoris and Ungernia. The growing demand for galanthamine has prompted searches for new sources of this compound, as well as other bioactive alkaloids for the treatment of AD. In this paper we report the isolation of the new alkaloid 11β-hydroxygalanthamine, an epimer of the previously isolated alkaloid habranthine, which was identified using NMR techniques. It has been shown that 11β-hydroxygalanthamine has an important in vitro acetylcholinesterase inhibitory activity. Additionally, Hippeastrum papilio yielded substantial quantities of galanthamine.

  5. Analysis of Ergot Alkaloids

    Directory of Open Access Journals (Sweden)

    Colin Crews

    2015-06-01

    Full Text Available The principles and application of established and newer methods for the quantitative and semi-quantitative determination of ergot alkaloids in food, feed, plant materials and animal tissues are reviewed. The techniques of sampling, extraction, clean-up, detection, quantification and validation are described. The major procedures for ergot alkaloid analysis comprise liquid chromatography with tandem mass spectrometry (LC-MS/MS and liquid chromatography with fluorescence detection (LC-FLD. Other methods based on immunoassays are under development and variations of these and minor techniques are available for specific purposes.

  6. Simple Indolizidine and Quinolizidine Alkaloids.

    Science.gov (United States)

    Michael, Joseph P

    2016-01-01

    This review of simple indolizidine and quinolizidine alkaloids (i.e., those in which the parent bicyclic systems are in general not embedded in polycyclic arrays) is an update of the previous coverage in Volume 55 of this series (2001). The present survey covers the literature from mid-1999 to the end of 2013; and in addition to aspects of the isolation, characterization, and biological activity of the alkaloids, much emphasis is placed on their total synthesis. A brief introduction to the topic is followed by an overview of relevant alkaloids from fungal and microbial sources, among them slaframine, cyclizidine, Steptomyces metabolites, and the pantocins. The important iminosugar alkaloids lentiginosine, steviamine, swainsonine, castanospermine, and related hydroxyindolizidines are dealt with in the subsequent section. The fourth and fifth sections cover metabolites from terrestrial plants. Pertinent plant alkaloids bearing alkyl, functionalized alkyl or alkenyl substituents include dendroprimine, anibamine, simple alkaloids belonging to the genera Prosopis, Elaeocarpus, Lycopodium, and Poranthera, and bicyclic alkaloids of the lupin family. Plant alkaloids bearing aryl or heteroaryl substituents include ipalbidine and analogs, secophenanthroindolizidine and secophenanthroquinolizidine alkaloids (among them septicine, julandine, and analogs), ficuseptine, lasubines, and other simple quinolizidines of the Lythraceae, the simple furyl-substituted Nuphar alkaloids, and a mixed quinolizidine-quinazoline alkaloid. The penultimate section of the review deals with the sizable group of simple indolizidine and quinolizidine alkaloids isolated from, or detected in, ants, mites, and terrestrial amphibians, and includes an overview of the "dietary hypothesis" for the origin of the amphibian metabolites. The final section surveys relevant alkaloids from marine sources, and includes clathryimines and analogs, stellettamides, the clavepictines and pictamine, and bis

  7. The Securinega alkaloids.

    Science.gov (United States)

    Chirkin, Eqor; Atkatlian, William; Porée, François-Hugues

    2015-01-01

    Securinega alkaloids represent a family of plant secondary metabolites known for 50 years. Securinine (1), the most abundant and studied alkaloid of this series was isolated by Russian researchers in 1956. In the following years, French and Japanese scientists reported other Securinega compounds and extensive work was done to elucidate their intriguing structures. The homogeneity of this family relies mainly on its tetracyclic chemical backbone, which features a butenolide moiety (cycle D) and an azabicyclo[3.2.1]octane ring system (rings B and C). Interestingly, after a period of latency of 20 years, the Securinega topic reemerged as a prolific source of new natural structures and to date more than 50 compounds have been identified and characterized. The oligomeric subgroup gathering dimeric, trimeric, and tetrameric units is of particular interest. The unprecedented structure of the Securinega alkaloids was the subject of extensive synthetic efforts culminating in several efficient and elegant total syntheses. The botanical distribution of these alkaloids seems limited to the Securinega, Flueggea, Margaritaria, and Breynia genera (Phyllanthaceae). However, only a limited number of plant species have been considered for their alkaloid contents, and additional phytochemical as well as genetic studies are needed. Concerning the biosynthesis, experiments carried out with radiolabelled aminoacids allowed to identify lysine and tyrosine as the precursors of the piperidine ring A and the CD rings of securinine (1), respectively. Besides, plausible biosynthetic pathways were proposed for virosaine A (38) and B (39), flueggine A (46), and also the different oligomers flueggenine A-D (48-51), fluevirosinine A (56), and flueggedine (20). The case of nirurine (45) and secu'amamine (37) remains elusive and additional studies seem necessary to understand their mode of production. The scope of biological of activities of the Securinega alkaloids was mainly centered on the CNS

  8. Alkaloids in Bulgarian Pancratium maritimum L.

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    Berkov, Strahil; Evstatieva, Luba; Popov, Simeon

    2004-01-01

    A GC/MS analysis of alkaloids from leaves, bulbs and roots of Pancratium maritimum was performed. From the identified 16 alkaloids, 5 alkaloids were reported for the first time for this plant. Several compounds with pharmacological activity were found. Haemanthamine was main alkaloid in the leaves and bulbs whereas galanthane was found to be main alkaloid in roots.

  9. Quinolizidine alkaloids from Lupinus lanatus

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    Neto, Alexandre T.; Oliveira, Carolina Q.; Ilha, Vinicius; Pedroso, Marcelo; Burrow, Robert A.; Dalcol, Ionara I.; Morel, Ademir F.

    2011-10-01

    In this study, one new quinolizidine alkaloid, lanatine A ( 1), together with three other known alkaloids, 13-α- trans-cinnamoyloxylupanine ( 2), 13-α-hydroxylupanine ( 3), and (-)-multiflorine ( 4) were isolated from the aerial parts of Lupinus lanatus (Fabaceae). The structures of alkaloids 1- 4 were elucidated by spectroscopic data analysis. The stereochemistry of 1 was determined by single crystal X-ray analysis. Bayesian statistical analysis of the Bijvoet differences suggests the absolute stereochemistry of 1. In addition, the antimicrobial potential of alkaloids 1- 4 is also reported.

  10. Alkaloids from Galanthus nivalis.

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    Berkov, Strahil; Codina, Carles; Viladomat, Francesc; Bastida, Jaume

    2007-07-01

    Phytochemical studies on Galanthus nivalis of Bulgarian origin resulted in the isolation of five compounds: 11-O-(3'-hydroxybutanoyl)hamayne, 3,11-O-(3',3''-dihydroxybutanoyl)hamayne, 3-O-(2''-butenoyl)-11-O-(3'-hydroxybutanoyl)hamayne, 3,11,3''-O-(3',3'',3'''-trihydroxybutanoyl)hamayne, and 2-O-(3'-acetoxybutanoyl)lycorine, together with five known alkaloids: ungeremine, lycorine, tazettine, hamayne, and ismine. Their structures were determined by (1)H and (13)C NMR spectroscopy and two-dimensional (1)H-(1)H and (1)H-(13)C chemical shift correlation experiments.

  11. Cytochrome P450 as dimerization catalyst in diketopiperazine alkaloid biosynthesis.

    Science.gov (United States)

    Saruwatari, Takayoshi; Yagishita, Fumitoshi; Mino, Takashi; Noguchi, Hiroshi; Hotta, Kinya; Watanabe, Kenji

    2014-03-21

    As dimeric natural products frequently exhibit useful biological activities, identifying and understanding their mechanisms of dimerization is of great interest. One such compound is (−)-ditryptophenaline, isolated from Aspergillus flavus, which inhibits substance P receptor for potential analgesic and anti-inflammatory activity. Through targeted gene knockout in A. flavus and heterologous yeast gene expression, we determined for the first time the gene cluster and pathway for the biosynthesis of a dimeric diketopiperazine alkaloid. We also determined that a single cytochrome P450, DtpC, is responsible not only for pyrroloindole ring formation but also for concurrent dimerization of N-methylphenylalanyltryptophanyl diketopiperazine monomers into a homodimeric product. Furthermore, DtpC exhibits relaxed substrate specificity, allowing the formation of two new dimeric compounds from a non-native monomeric precursor, brevianamide F. A radical-mediated mechanism of dimerization is proposed.

  12. Transcription factors in alkaloid biosynthesis.

    Science.gov (United States)

    Yamada, Yasuyuki; Sato, Fumihiko

    2013-01-01

    Higher plants produce a large variety of low-molecular weight secondary compounds. Among them, nitrogen-containing alkaloids are the most biologically active and are often used pharmaceutically. Whereas alkaloid chemistry has been intensively investigated, alkaloid biosynthesis, including the relevant biosynthetic enzymes, genes and their regulation, and especially transcription factors, is largely unknown, as only a limited number of plant species produce certain types of alkaloids and they are difficult to study. Recently, however, several groups have succeeded in isolating the transcription factors that are involved in the biosynthesis of several types of alkaloids, including bHLH, ERF, and WRKY. Most of them show Jasmonate (JA) responsiveness, which suggests that the JA signaling cascade plays an important role in alkaloid biosynthesis. Here, we summarize the types and functions of transcription factors that have been isolated in alkaloid biosynthesis, and characterize their similarities and differences compared to those in other secondary metabolite pathways, such as phenylpropanoid and terpenoid biosyntheses. The evolution of this biosynthetic pathway and regulatory network, as well as the application of these transcription factors to metabolic engineering, is discussed.

  13. Potent immunosuppressive principles, dimeric sesquiterpene thioalkaloids, isolated from nupharis rhizoma, the rhizoma of Nuphar pumilum (nymphaeaceae): structure-requirement of nuphar-alkaloid for immunosuppressive activity.

    Science.gov (United States)

    Yamahara, J; Shimoda, H; Matsuda, H; Yoshikawa, M

    1996-09-01

    Potent immunosuppressants, the dimeric sesquiterpene thioalkaloids, 6-hydroxythiobinupharidine (2), 6,6'-dihydroxythiobinupharidine (3), 6-hydroxythionuphlutine B (5) and 6'-hydroxythionuphlutine B (6), were isolated from a natural medicine, Nupharis Rhizoma, the rhizoma of Nuphar pumilum (TIMM.) DC., through bioassay-guided separation together with five quinolizidine alkaloids (8, 9, 10, 11, 12). Dimeric sesquiterpene thioalkaloids (2, 3, 5, 6) were found to significantly inhibit anti-sheep erythrocyte plaque forming cell formation in mice spleen cells at 10(-6) M concentration. At this concentration, 2, 5 and 6 were found to exhibit no cytotoxicity to mice spleen cells, and 3 also showed only a little cytotoxicity. In addition, the inhibitory activity of several Nuphar alkaloids, dimeric sesquiterpene thioalkaloids (1, 4, 7, 8), and monomeric sesquiterpene alkaloids (9, 10, 11, 12) on anti-sheep erythrocyte plaque forming cell formation was examined and some structural requirement of Nuphar alkaloid for immunosuppressive activity was determined.

  14. A strategy for complex dimer formation when biomimicry fails: total synthesis of ten coccinellid alkaloids.

    Science.gov (United States)

    Sherwood, Trevor C; Trotta, Adam H; Snyder, Scott A

    2014-07-09

    Although dimeric natural products can often be synthesized in the laboratory by directly merging advanced monomers, these approaches sometimes fail, leading instead to non-natural architectures via incorrect unions. Such a situation arose during our studies of the coccinellid alkaloids, when attempts to directly dimerize Nature's presumed monomeric precursors in a putative biomimetic sequence afforded only a non-natural analogue through improper regiocontrol. Herein, we outline a unique strategy for dimer formation that obviates these difficulties, one which rapidly constructs the coccinellid dimers psylloborine A and isopsylloborine A through a terminating sequence of two reaction cascades that generate five bonds, five rings, and four stereocenters. In addition, a common synthetic intermediate is identified which allows for the rapid, asymmetric formal or complete total syntheses of eight monomeric members of the class.

  15. Pyrrolizidine alkaloids from Heliotropium indicum

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Joao Sammy N.; Machado, Luciana L.; Pessoa, Otilia D.L.; Lemos, Telma L.G. [Ceara Univ., Fortaleza, CE (Brazil). Dept. de Quimica Organica e Inorganica]. E-mail: tlemos@dqoi.ufc.br; Braz-Filho, Raimundo [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacases, RJ (Brazil). Setor de Quimica de Produtos Naturais; Overk, Cassia R.; Ping Yao; Cordell, Geoffrey A. [University of Illinois at Chicago, IL (United States). College of Pharmacy. Dept. of Medicinal Chemistry and Pharmacognosy

    2005-11-15

    ndicine (1), a new pyrrolizidine alkaloid with unusual structural features, together with the known lycopsamine (2), were isolated from the roots of Heliotropium indicum (Boraginaceae). The structures were established by a combination of 1D and 2D NMR methods (COSY, HMQC, HMBC, and NOESY) and HREIMS. This is the first report of a lactone pyrrolizidine alkaloid in the genus Heliotropium. Compounds 1 and 2 were assayed for antioxidant activity and showed moderate activity. (author)

  16. How acidic are monomeric structural units of heparin?

    Science.gov (United States)

    Remko, Milan; Broer, Ria; Van Duijnen, Piet Th.

    2013-12-01

    Density functional theory methods with the B3LYP functional have been used to letter the acidity of carboxyl, O-sulfo and N-sulfo groups in six basic monomeric structural units of heparin (1-OMe ΔUA-2S, 1-OMe GlcN-S6S, 1,4-DiOMe GlcA, 1,4-DiOMe GlcN-S3S6S, 1,4-DiOMe IdoA-2S, and 1,4-DiOMe GlcN-S6S). The predicted gas-phase acidity of the acidic functional groups in the monomeric structural units of heparin is: O-sulfo > N-sulfo > carboxyl. The computed pKa values provide the same order of acidity as was observed in water solution. This implies that hydration does not change ordering of acidity of major acidic groups of monomeric structural units of heparin.

  17. Total Synthesis of Securinega Alkaloids

    Institute of Scientific and Technical Information of China (English)

    T. Honda

    2005-01-01

    @@ 1Introduction Naturally occurring Securinega alkaloids (1-4) (Fig. 1)[1], with their wide range of structural and stereochemical features, continue to provide challenging synthetic targets, since these alkaloids exhibit attractive biological activities. Securinine (1), isolated from Securinega suffruticosa [2], was structurally determined to contain an indolizidine skeleton with an azabicyclo[3.2.1 ]octane system together with an α, β-unsaturated γ-lactone ring. This alkaloid has been clinically used in Russia as a CNS stimulating drug[3], and has been shown to act as a stereospecific antagonist at the GABA binding site of the GABAA-receptor complex[4].Viroallosecurinine (2), a diastereoisomeric alkaloid of securinine, was also isolated from the leaves of Securinega virosa[5] as a cytotoxic alkaloid exhibiting a MIC of 0.48 μg/mL for Ps. aeruginosa and Staph.aureus[6]. This alkaloid is recognized to be bactericidal since the yields of MIC/MBC were less than 1[7].

  18. Genotoxicity of pyrrolizidine alkaloids.

    Science.gov (United States)

    Chen, Tao; Mei, Nan; Fu, Peter P

    2010-04-01

    Pyrrolizidine alkaloids (PAs) are common constituents of many plant species around the world. PA-containing plants are probably the most common poisonous plants affecting livestock and wildlife. They can inflict harm to humans through contaminated food sources, herbal medicines and dietary supplements. Half of the identified PAs are genotoxic and many of them are tumorigenic. The mutagenicity of PAs has been extensively studied in different biological systems. Upon metabolic activation, PAs produce DNA adducts, DNA cross-linking, DNA breaks, sister chromatid exchange, micronuclei, chromosomal aberrations, gene mutations and chromosome mutations in vivo and in vitro. PAs induced mutations in the cII gene of rat liver and in the p53 and K-ras genes of mouse liver tumors. It has been suggested that all PAs produce a set of (+/-)-6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine-derived DNA adducts and similar types of gene mutations. The signature types of mutations are G : C --> T : A transversion and tandem base substitutions. Overall, PAs are mutagenic in vivo and in vitro and their mutagenicity appears to be responsible for the carcinogenesis of PAs.

  19. Homotropic cooperativity of monomeric cytochrome P450 3A4

    Energy Technology Data Exchange (ETDEWEB)

    Baas, Bradley J.; Denisov, Ilia G.; Sligar, Stephen G. (UIUC)

    2010-11-16

    Mechanistic studies of mammalian cytochrome P450s are often obscured by the phase heterogeneity of solubilized preparations of membrane enzymes. The various protein-protein aggregation states of microsomes, detergent solubilized cytochrome or a family of aqueous multimeric complexes can effect measured substrate binding events as well as subsequent steps in the reaction cycle. In addition, these P450 monooxygenases are normally found in a membrane environment and the bilayer composition and dynamics can also effect these catalytic steps. Here, we describe the structural and functional characterization of a homogeneous monomeric population of cytochrome P450 3A4 (CYP 3A4) in a soluble nanoscale membrane bilayer, or Nanodisc [Nano Lett. 2 (2002) 853]. Cytochrome P450 3A4:Nanodisc assemblies were formed and purified to yield a 1:1 ratio of CYP 3A4 to Nanodisc. Solution small angle X-ray scattering was used to structurally characterize this monomeric CYP 3A4 in the membrane bilayer. The purified CYP 3A4:Nanodiscs showed a heretofore undescribed high level of homotropic cooperativity in the binding of testosterone. Soluble CYP 3A4:Nanodisc retains its known function and shows prototypic hydroxylation of testosterone when driven by hydrogen peroxide. This represents the first functional characterization of a true monomeric preparation of cytochrome P450 monooxygenase in a phospholipid bilayer and elucidates new properties of the monomeric form.

  20. Monomeric tartrate resistant acid phosphatase induces insulin sensitive obesity.

    Directory of Open Access Journals (Sweden)

    Pernilla Lång

    Full Text Available BACKGROUND: Obesity is associated with macrophage infiltration of adipose tissue, which may link adipose inflammation to insulin resistance. However, the impact of inflammatory cells in the pathophysiology of obesity remains unclear. Tartrate resistant acid phosphatase (TRAP is an enzyme expressed by subsets of macrophages and osteoclasts that exists either as an enzymatically inactive monomer or as an active, proteolytically processed dimer. PRINCIPAL FINDINGS: Using mice over expressing TRAP, we show that over-expression of monomeric, but not the dimeric form in adipose tissue leads to early onset spontaneous hyperplastic obesity i.e. many small fat cells. In vitro, recombinant monomeric, but not proteolytically processed TRAP induced proliferation and differentiation of mouse and human adipocyte precursor cells. In humans, monomeric TRAP was highly expressed in the adipose tissue of obese individuals. In both the mouse model and in the obese humans the source of TRAP in adipose tissue was macrophages. In addition, the obese TRAP over expressing mice exhibited signs of a low-grade inflammatory reaction in adipose tissue without evidence of abnormal adipocyte lipolysis, lipogenesis or insulin sensitivity. CONCLUSION: Monomeric TRAP, most likely secreted from adipose tissue macrophages, induces hyperplastic obesity with normal adipocyte lipid metabolism and insulin sensitivity.

  1. Copper catalysed synthesis of indolylquinazolinone alkaloid bouchardatine

    Indian Academy of Sciences (India)

    Mayavan Viji; Rajagopal Nagarajan

    2014-07-01

    We describe the total synthesis of indolylquinazolinone alkaloid bouchardatine and some of the quinazolinone derivatives. The aerobic oxidation induced by copper(I) bromide, followed by Vilsmeier-Haack formylation gives the natural product bouchardatine alkaloid in good yield.

  2. The Chemistry of the Akuammiline Alkaloids.

    Science.gov (United States)

    Adams, Gregory L; Smith, Amos B

    2016-01-01

    An update on the literature covering the akuammiline family of alkaloids is presented. This chapter begins with a summary of new akuammiline alkaloids reported since 2000 and is followed by an overview of new reported bioactivities of akuammiline alkaloids since 2000. The remainder of the chapter comprises a comprehensive review of the synthetic chemistry that has been reported in the last 50 years concerning akuammiline alkaloids and their structural motifs.

  3. FIVE NEW NORDITERPENOID ALKALOIDS FROM ACONITUM SINOMONTANUM

    Institute of Scientific and Technical Information of China (English)

    FENG-PENG WANG; CHONG-SHENG PENG; XI-XIAN JIAN; DONG-LIN CHEN

    2001-01-01

    From the roots of A conitum sinomontanum, five new norditerpenoid alkaloids, sinomontanitines A (1) and B (2), sinomontanines A (3), B (4) and C (5), were isolated together with the known alkaloids lappaconitine (6) and ranaconitine (7), The structures of the new alkaloids were determined by spectral analysis.

  4. Alkaloids from Stems of Ervatamia yunnanensis (Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    Shuang LIANG; Xin Gen LUO; Hai Sheng CHEN; Xiao Dong ZHANG; Mao HUANG; Wen Yong LIU

    2006-01-01

    Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis. Among them, 10-hydroxy-19, 20-dihydroisositsirikine (Ⅰ) is new. The other five are known alkaloids,namely: matrine (Ⅱ), 19, 20-dihydroisositsuikine (Ⅲ), 19-s-voacangarine (Ⅳ), 11'-methoxyl- 19s-heyneanine (Ⅴ), conodurine (Ⅵ). The structural elucidation of the alkaloids was based on spectral means.

  5. Alkaloids from stems of Ervatamia yunnanensis

    Institute of Scientific and Technical Information of China (English)

    Xin Gen Luo; Hai Sheng Chen; Shuang Liang; Mao Huang; Wei Dong Xuan; Li Jin

    2007-01-01

    Six indole alkaloids were isolated from the stems of Ervatamia yunnanensis.Among them, yunnanensine (Ⅰ) is new.The other five are known alkaloids, namely: 19,20-E-vallesamine (Ⅱ), 19s-heyneanine (Ⅲ), ibogaine (Ⅳ), ibogamine (Ⅴ), coronaridine (Ⅵ).The structural elucidation of the alkaloids was based on spectral means.

  6. New extraction technique for alkaloids

    Directory of Open Access Journals (Sweden)

    Djilani Abdelouaheb

    2006-01-01

    Full Text Available A method of extraction of natural products has been developed. Compared with existing methods, the new technique is rapid, more efficient and consumes less solvent. Extraction of alkaloids from natural products such as Hyoscyamus muticus, Datura stramonium and Ruta graveolens consists of the use of a sonicated solution containing a surfactant as extracting agent. The alkaloids are precipitated by Mayer reagent, dissolved in an alkaline solution, and then extracted with chloroform. This article compares the results obtained with other methods showing clearly the advantages of the new method.

  7. The alkaloid profiles of Lupinus sulphureus.

    Science.gov (United States)

    Cook, Daniel; Lee, Stephen T; Gardner, Dale R; Pfister, James A; Welch, Kevin D; Green, Benedict T; Davis, T Zane; Panter, Kip E

    2009-02-25

    Lupines are common plants on the rangelands in the western United States. Lupines contain alkaloids that can be toxic and teratogenic causing congenital birth defects (crooked calf disease). One such lupine, Lupinus sulphureus, occurs in parts of Oregon, Washington, and British Columbia. Specimens of L. sulphureus from field collections and herbaria were evaluated taxonomically and by chemical means. A total of seven distinct alkaloid profiles and the individual alkaloids associated with each profile were identified. Each alkaloid profile was unique in its geographical distribution and its potential risk to livestock. In conclusion, taxonomic classification is not sufficient to determine risk, as chemical characterization of the alkaloids must also be performed.

  8. Alkaloids with antioxidant activities from Aconitum handelianum.

    Science.gov (United States)

    Yin, Tian-Peng; Cai, Le; Xing, Yun; Yu, Jing; Li, Xue-Jiao; Mei, Rui-Feng; Ding, Zhong-Tao

    2016-06-01

    A new C20-diterpenoid alkaloid handelidine (1) and twenty-seven known alkaloids (2-28) were isolated from the roots of Aconitum handelianum. Their structures were established on the basis of extensive spectroscopic analyses. The study indicated that denudatine-type C20-diterpenoid alkaloids with vicinal-triol system and benzyltetrahydroisoquinoline alkaloids exhibited significant antioxidant activities measured by three antioxidant test systems. The aconitine-type C19-diterpenoid alkaloids could serve as potential secondary antioxidants for their strong binding effects to metal ions.

  9. Structural and quantitative analysis of Equisetum alkaloids.

    Science.gov (United States)

    Cramer, Luise; Ernst, Ludger; Lubienski, Marcus; Papke, Uli; Schiebel, Hans-Martin; Jerz, Gerold; Beuerle, Till

    2015-08-01

    Equisetum palustre L. is known for its toxicity for livestock. Several studies in the past addressed the isolation and identification of the responsible alkaloids. So far, palustrine (1) and N(5)-formylpalustrine (2) are known alkaloids of E. palustre. A HPLC-ESI-MS/MS method in combination with simple sample work-up was developed to identify and quantitate Equisetum alkaloids. Besides the two known alkaloids six related alkaloids were detected in different Equisetum samples. The structure of the alkaloid palustridiene (3) was derived by comprehensive 1D and 2D NMR experiments. N(5)-Acetylpalustrine (4) was also thoroughly characterized by NMR for the first time. The structure of N(5)-formylpalustridiene (5) is proposed based on mass spectrometry results. Twenty-two E. palustre samples were screened by a HPLC-ESI-MS/MS method after development of a simple sample work-up and in most cases the set of all eight alkaloids were detected in all parts of the plant. A high variability of the alkaloid content and distribution was found depending on plant organ, plant origin and season ranging from 88 to 597mg/kg dried weight. However, palustrine (1) and the alkaloid palustridiene (3) always represented the main alkaloids. For the first time, a comprehensive identification, quantitation and distribution of Equisetum alkaloids was achieved.

  10. Historical view on ergot alkaloids.

    Science.gov (United States)

    Hofmann, A

    1978-01-01

    A short survey of the history of ergot, of the original and, for a long time, only source of ergot alkaloids, is given. Once a dreaded poison, ergot has changed its role over the centuries to become a rich treasure house of valuable pharmaceuticals. In the Middle Ages it was the cause of epidemics of ergotism, which cost tens of thousands of people their lives. Ergot was first mentioned by the German physician Lonitzer in 1582 as a remedy used by midwives for quickening childbirth. The isolation of pharmacologically useful alkaloids started in 1906 with the discovery of ergotoxine and its adrenolytic activity by Barger, Carr and Dale. In 1918, Stoll isolated ergotamine, the first chemically pure ergot alkaloid, which found widespread therapeutic use in obstetrics and internal medicine. In 1935 the specific oxytocic principle of ergot, ergonovine, was discovered simultaneously in four separate laboratories. Since then, worldwide investigations on ergot alkaloids resulted in the elucidation of their structures and total syntheses and preparation of valuable therapeutics such as Methergine, Hydergine, Dihydergot, and others.

  11. Lycopodium alkaloids from Palhinhaea cernua

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Fu-Wei [Graduate University of Chinese Academy of Sciences, Beijing (China); Luo, Ji-Feng; Wang, Yue-Hu, E-mail: wangyuehu@mail.kib.ac.cn [Key Laboratory of Economic Plants and Biotechnology, Kunming Institute of Botany, Chinese Academy of Sciences (China); Sun, Qian-Yun; Yang, Fu-Mei [Key Laboratory of Chemistry for Natural Products, Guizhou Province and Chinese Academy of Sciences (China); Liu, Fang [College of Landscape and Horticulture, Yunnan Agricultural University (China); Long, Chun-Lin, E-mail: long@mail.kib.ac.cn [College of Life and Environmental Sciences, Minzu University of China, Beijing, (China)

    2012-07-01

    Two new Lycopodium alkaloids, acetyllycoposerramine M and palcernine A were isolated from whole plant extracts of Palhinhaea cernua L. together with ten previously identified compounds. The structures of the new compounds were elucidated by spectroscopic methods and single-crystal X-ray diffraction analyses using the Flack parameter. (author)

  12. Synthesis and structure of monomeric, trimeric, and mixed phenylcyanamides.

    Science.gov (United States)

    Brand, Harald; Mayer, Peter; Schulz, Axel; Soller, Thomas; Villinger, Alexander

    2008-06-02

    In a new synthetic approach phenylcyanamide (Hpca) was synthesized by methylation of phenylthiourea followed by a basic work-up. All products along the synthetic route have been fully characterized by means of NMR, IR, and X-ray studies. The first structural report of neutral mixed crystals of phenylcyanamide containing monomeric and trimeric Hpca is presented. Examination of these intriguing mixed crystals revealed the formation of distinct layers of monomeric and trimeric Hpca. These layers are interconnected by weak hydrogen bonds. The trimer represents triphenylisomelamine, which readily isomerizes to the triphenylmelamine in the melt, in accord with computations at the B3LYP level, indicating an exothermic process (DeltaH = -49.4 kcal mol(-1)). Pure trimeric Hpca (triphenylisomelamine) was obtained either by recrystallization of the mixed crystals from boiling water or by trimerization of monomeric Hpca in isopropanol for 12 h under reflux conditions. For comparison tritylcyanamide (Htca) and potassium phenylcyanamide as an [18]crown-6 complex [K([18]crown-6)pca] have been synthesized, and the solid-state structures were determined using X-ray diffraction techniques. The thermal behavior was studied by thermo-analytical experiments. In agreement with the experimental results, computations predict an exothermic cyclotrimerization process for Hpca (DeltaH = -41.3 kcal mol(-1)).

  13. Angustilobine and andranginine type indole alkaloids and an uleine-secovallesamine bisindole alkaloid from Alstonia angustiloba.

    Science.gov (United States)

    Ku, Wai-Foong; Tan, Shin-Jowl; Low, Yun-Yee; Komiyama, Kanki; Kam, Toh-Seok

    2011-12-01

    A total of 20 alkaloids were isolated from the leaf and stem-bark extracts of Alstonia angustiloba, of which two are hitherto unknown. One is an alkaloid of the angustilobine type (angustilobine C), while the other is a bisindole alkaloid angustiphylline, derived from the union of uleine and secovallesamine moieties. The structures of these alkaloids were established using NMR and MS analysis. Angustilobine C showed moderate cytotoxicity towards KB cells.

  14. Pyrrolizidine alkaloids of senecio sp from Peru

    Directory of Open Access Journals (Sweden)

    Liliana Ruiz Vásquez and Matías Reina Artiles

    2011-01-01

    Full Text Available Six pyrrolizidine alkaloids (PAs (two saturated macrocyclic, three unsaturated macrocyclic and one unsaturated seco-macrocyclic were isolated from native Peruvian Senecio species. The structures of these alkaloids were established by a complete NMR spectroscopic analysis, chemical transformations and comparison of their NMR data with those published for similar alkaloids. Three PAs were then tested for antifungal activity against Fusarium moniliforme, F. (Sheldon, F. oxysporum fs. lycopersici (Scheldt and F. solani (Mart, no significant activity being observed.

  15. Pyrrolizidine alkaloids of senecio sp from Peru

    OpenAIRE

    2011-01-01

    Six pyrrolizidine alkaloids (PAs) (two saturated macrocyclic, three unsaturated macrocyclic and one unsaturated seco-macrocyclic) were isolated from native Peruvian Senecio species. The structures of these alkaloids were established by a complete NMR spectroscopic analysis, chemical transformations and comparison of their NMR data with those published for similar alkaloids. Three PAs were then tested for antifungal activity against Fusarium moniliforme, F. (Sheldon), F. oxysporum fs. lycopers...

  16. New aporphine alkaloids of Ocotea minarum.

    Science.gov (United States)

    Vecchietti, V; Casagrande, C; Ferrari, G; Severini Ricca, G

    1979-10-01

    Fourteen aporphine alkaloids were isolated from the leaves of a Brazilian Lauracea, Ocotea minarum Nees (Mez). The known alkaloids were identified through their physico-chemical properties as: leucoxylonine (VII), dicentrine (IV), ocoteine (V), leucoxine (VI), ocopodine (VIII), predicentrine (IX), dicentrinone (XIV) and thalicminine (XV). Six new aporphine alkaloids were also isolated: ocotominarine (I), ocominarine (III), nor-leucoxylonine (XI), iso-oconovine (xii), 4-hydroxydicentrine (XIII) and ocominarone (XVI). Their structures were determined using spectroscopic methods and chemical correlations.

  17. Pyrrolizidine alkaloids of Senecio sp from Peru

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Vasquez, Liliana; Reina Artiles, Matias [Instituto de Productos Naturales y Agrobiologia, CSIC, Tenerife (Spain); Gonzalez Coloma, Azucena [Instituto de Ciencias Agrarias (ICA), CSIC, Madrid (Spain); Cabrera Perez, Raimundo [Universidad de La Laguna (ULL), Tenerife (Spain). Unidad de Fitopatologia, Facultad de Biologia; Ruiz Mesia, Lastenia [Universidad Nacional de la Amazonia Peruana (LIPNAA-UNAP), AA.HH. Nuevo San Lorenzo, San Juan, Iquitos (Peru). Lab. de Investigacion en Productos Naturales Antiparasitarios de la Amazonia

    2011-07-01

    Six pyrrolizidine alkaloids (PAs) (two saturated macrocyclic, three unsaturated macrocyclic and one unsaturated seco-macrocyclic) were isolated from native Peruvian Senecio species. The structures of these alkaloids were established by a complete NMR spectroscopic analysis, chemical transformations and comparison of their NMR data with those published for similar alkaloids. Three PAs were then tested for antifungal activity against Fusarium moniliforme, F. (Sheldon), F. oxysporum fs. lycopersici (Scheldt) and F. solani (Mart), no significant activity being observed. (author)

  18. Four new fluorenone alkaloids and one new dihydroazafluoranthene alkaloid from Caulophyllum robustum Maxim.

    Science.gov (United States)

    Wang, Xiao-Ling; Liu, Bing-Rui; Chen, Chien-Kuang; Wang, Jun-Ru; Lee, Shoei-Sheng

    2011-09-01

    Four new fluorenone alkaloids, caulophylline A-D (1-4), and one new dihydroazafluoranthene alkaloid, caulophylline E (5) were isolated from the roots of Caulophyllum robustum Maxim. Their structures were elucidated by spectroscopic analysis. Among the isolated alkaloids, Caulophylline E showed good scavenging effects against DPPH radical with IC(50) of 39 μM.

  19. Pyrrolizidine alkaloids from Onosma erecta.

    Science.gov (United States)

    Damianakos, Harilaos; Sotiroudis, Georgios; Chinou, Ioanna

    2013-10-25

    The MeOH extract of the aerial parts of Onosma erecta afforded four new pyrrolizidine alkaloids, 7-O-acetylechinatine N-oxide (1), a viridinatine N-oxide stereoisomer (2), 7-epi-echimiplatine N-oxide (3), and onosmerectine N-oxide (4), and two additional new natural products, the acid 2,3-dimethyl-2,3,4-trihydroxypentanoic acid (5) and the acyloin 4-methyl-2-hydroxypentanone (6).

  20. New alkaloids from Pancratium maritimum.

    Science.gov (United States)

    Ibrahim, Sabrin R M; Mohamed, Gamal A; Shaala, Lamiaa A; Youssef, Diaa T A; El Sayed, Khalid A

    2013-10-01

    As a part of ongoing search efforts for the discovery of anticancer lead entities from natural sources, bulbs and flowers of the amaryllidaceous plant Pancratium maritimum have been investigated. Fractionation of the extracts of the fresh flowers and bulbs of P. maritimum led to the isolation of four new alkaloids, namely pancrimatines A (1) and B (2), norismine (3), and pancrimatine C (4), together with the previously reported N-methyl-8,9-methylenedioxy-6-phenanthridone (5), trispheridine (6), and N-methyl-8,9-methylenedioxyphenanthridine (7). The structures of these alkaloids were established on the basis of extensive 1D and 2D NMR and high-resolution mass spectral analyses as well as comparison with the literature. Compounds 2 and 7 showed antiproliferative and antimigratory activity against the highly metastatic human prostate cancer cell line PC-3 cells without cytotoxicity. The phenanthridine alkaloid class was identified as having potential for use to control prostate cancer proliferation and migration. Georg Thieme Verlag KG Stuttgart · New York.

  1. Slow Unfolding of Monomeric Proteins from Hyperthermophiles with Reversible Unfolding

    Directory of Open Access Journals (Sweden)

    Atsushi Mukaiyama

    2009-03-01

    Full Text Available Based on the differences in their optimal growth temperatures microorganisms can be classified into psychrophiles, mesophiles, thermophiles, and hyperthermophiles. Proteins from hyperthermophiles generally exhibit greater stability than those from other organisms. In this review, we collect data about the stability and folding of monomeric proteins from hyperthermophilies with reversible unfolding, from the equilibrium and kinetic aspects. The results indicate that slow unfolding is a general strategy by which proteins from hyperthermophiles adapt to higher temperatures. Hydrophobic interaction is one of the factors in the molecular mechanism of the slow unfolding of proteins from hyperthermophiles.

  2. Addition-type polyimides from solutions of monomeric reactants

    Science.gov (United States)

    Delvigs, P.; Serafini, T. T.; Lightsey, G. R.

    1972-01-01

    The monomeric reactants approach was used to fabricate addition-type polyimide/graphite fiber composites with improved mechanical properties and thermal stability characteristics over those of composites derived from addition-type amide acid prepolymers. A screening study of 24 different monomer combinations was performed. The results of a more extensive investigation of a selected number of monomer combinations showed that the combination providing the best thermomechanical properties was 5-norbornene-2,3-dicarboxylic acid monomethyl ester/4,4'-methylenedianiline/3,3'4,4'-benzophenone tetracarboxylic acid dimethyl ester at a molar ratio of 2/3.09/2.09.

  3. Six new alkaloids from Melodinus henryi.

    Science.gov (United States)

    Ma, Ke; Wang, Jun-Song; Luo, Jun; Kong, Ling-Yi

    2015-01-01

    A total of six new alkaloids, melodinhenines A-F (1-6), were isolated from Melodinus henryi. Melodinhenines A and B are new eburnan-vindolinine-type bisindole alkaloids and melodinhenines C-F are new quinolinic melodinus alkaloids. Their structures were elucidated through extensive spectroscopic methods including 2D NMR and HRESIMS analyses. The absolute configuration of 1 and 2 was determined using ECD exciton chirality method. To the best of our knowledge, this is the first report on the determination of the absolute configuration of eburnan-vindolinine-type bisindole alkaloid using this method.

  4. Alkaloids produced by endophytic fungi: a review.

    Science.gov (United States)

    Zhang, Yanyan; Han, Ting; Ming, Qianliang; Wu, Lingshang; Rahman, Khalid; Qin, Luping

    2012-07-01

    In recent years, a number of alkaloids have been discovered from endophytic fungi in plants, which exhibited excellent biological properties such as antimicrobial, insecticidal, cytotoxic, and anticancer activities. This review mainly deals with the research progress on endophytic fungi for producing bioactive alkaloids such as quinoline and isoquinoline, amines and amides, indole derivatives, pyridines, and quinazolines. The biological activities and action mechanisms of these alkaloids from endophytic fungi are also introduced. Furthermore, the relationships between alkaloid-producing endophytes and their host plants, as well as their potential applications in the future are discussed.

  5. Characterization of monomeric intermediates during VSV glycoprotein structural transition.

    Directory of Open Access Journals (Sweden)

    Aurélie A Albertini

    2012-02-01

    Full Text Available Entry of enveloped viruses requires fusion of viral and cellular membranes, driven by conformational changes of viral glycoproteins. Crystal structures provide static pictures of pre- and post-fusion conformations of these proteins but the transition pathway remains elusive. Here, using several biophysical techniques, including analytical ultracentrifugation, circular dichroïsm, electron microscopy and small angle X-ray scattering, we have characterized the low-pH-induced fusogenic structural transition of a soluble form of vesicular stomatitis virus (VSV glycoprotein G ectodomain (G(th, aa residues 1-422, the fragment that was previously crystallized. While the post-fusion trimer is the major species detected at low pH, the pre-fusion trimer is not detected in solution. Rather, at high pH, G(th is a flexible monomer that explores a large conformational space. The monomeric population exhibits a marked pH-dependence and adopts more elongated conformations when pH decreases. Furthermore, large relative movements of domains are detected in absence of significant secondary structure modification. Solution studies are complemented by electron micrographs of negatively stained viral particles in which monomeric ectodomains of G are observed at the viral surface at both pH 7.5 and pH 6.7. We propose that the monomers are intermediates during the conformational change and thus that VSV G trimers dissociate at the viral surface during the structural transition.

  6. Intraspecific variability in the alkaloid metabolism of Galanthus elwesii.

    Science.gov (United States)

    Berkov, Strahil; Sidjimova, Borjana; Evstatieva, Luba; Popov, Simeon

    2004-03-01

    Alkaloid pattern of individuals from 16 Bulgarian Galanthus elwesii populations was investigated by GC/MS and TLC. Twenty-one Amaryllidaceae alkaloids were detected and 14 of them were identified. Crinane type alkaloids, haemanthamine or crinine, dominated alkaloid metabolism in most of the populations. With exception of one population, where the separate individuals showed variable alkaloid profiles (dominated by crinine or haemanthamine) the individuals of the rest of populations have identical and characteristic alkaloid profiles. Some populations showed remarkable differences in respect to their alkaloid pattern-type of biosynthesis, main alkaloids and number of alkaloids. Populations dominated by galanthamine type alkaloids were found as well. These data demonstrate that like the morphological features, the alkaloid metabolism of G. elwesii is also variable.

  7. Alkaloid variations in Catharanthus roseus seedlings treated by different temperatures in short term and long term

    Institute of Scientific and Technical Information of China (English)

    GUO Xiao-rui; YANG Lei; YU Jing-hua; TANG Zhong-hua; ZU Yuan-gang

    2007-01-01

    A study was conducted to investigate the effects of high temperature on variations of alkaloid metabolism in C. Roseus seedlings in Key Laboratory of Forest Plant Ecology, Northeast Forestry University, Heilongiang, China. 60-day-old C. Roseus seedlings with 3-4 pairs of leaves were incubated in chambers with temperature of 30℃ and 40℃ for short-term heat shock experiment and 20℃, 25℃ and 35℃ for long-term experiment. The contents ofvindoline, catharanthine, vinblastine and vincristine in C. Roseus leaves and root were checked at different temperatures in short term (1-6 h) and long term (1-16 d). Results showed that under short-term heat shock, the contents of vindoline,catharanthine and vinblastine in leaves of the seedlings were higher at 40℃ than at 30℃, but after 6 h treatment, the contents of vindoline and catharanthine under the two temperatures came to the same level. Catharanthine was exclusively distributed in C. Roseus roots and its content was increased by 40% after two hours incubation at 40℃, while increased slowly at 30℃ incubation and reached the highest value at 6 h. In the Long-term experiment, concentrations of monomeric alkaloids catharanthine and vindoline were higher at 20℃ than at 25℃ and had a sharp increase under the condition of 35℃. While for dimeric alkaloid, it showed that the higher the temperature, the earlier the peak value of vinblastine content appears. Vincristine had a continuous enhancement and attained 0.027 mg·g-1 at 16th day under 35℃ condition which was higher than those in the other conditions. It was concluded that high temperature could promote the accumulation of different alkaloids in C roseus and the accumulation characteristic is highly related to treatment time.

  8. Cytotoxic oxoisoaporphine alkaloids from Menispermum dauricum.

    Science.gov (United States)

    Yu, B W; Meng, L H; Chen, J Y; Zhou, T X; Cheng, K F; Ding, J; Qin, G W

    2001-07-01

    Four new oxoisoaporphine alkaloids, daurioxoisoporphines A-D (1-4), were isolated from the rhizomes of Menispermum dauricum. The structures of these alkaloids were established by spectroscopic methods. The cytotoxic evaluation of 1 and 2 is reported against four cancer cell lines.

  9. Alkaloids of some Asian Sedum species

    NARCIS (Netherlands)

    Kim, JH; THart, H; Stevens, JF

    1996-01-01

    The leafy parts of 16 Asian species belonging to the three sections of Sedum were investigated for the presence of alkaloids. Only in seven species of Sedum sect. Sedum were alkaloids found. Sedum bulbiferum, S. japonicum, S. lepidopodium, S. morrisomensis, S. oryzifolium, S. polytrichoides and S. s

  10. Alkaloids of the flowers of Pancratium maritimum.

    Science.gov (United States)

    Youssef, D T; Frahm, A W

    1998-10-01

    The defatted ethanolic extract of the fresh flowers of Pancratium maritimum L. yielded the four known alkaloids lycorine, maritidine, lycoramine, and galanthamine. The structures of the isolated alkaloids were determined mainly through spectroscopic studies including one- and two-dimensional NMR (COSY, NOESY, DEPT, HETCOR, and HMBC) and CD techniques. Some spectral data are newly reported or revised.

  11. New bisbenzylisoquinoline alkaloid from Laureliopsis philippiana

    DEFF Research Database (Denmark)

    Stærk, Dan; Thi, Loi Pham; Rasmussen, Hasse Bonde

    2009-01-01

    Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline...... alkaloid in Laureliopsis supports its close relationship to Atherosperma and its taxonomic segregation from Laurelia....

  12. Alkaloids from the Roots of Saccopetalum prolificum

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    A new alkaloid, named prolifine (1), was isolated along with four known alkaloids, liriodenine (2), 6-hydroxyonychine (3), isooncodine (4) and discretamine (5) from the roots of Saccopetalum prolificum. The structure of 1 was elucidated on the basis of spectroscopic and chemical methods.

  13. Alkaloids of Nelumbo lutea (Wild.) pers. (Nymphaeaceae)

    Science.gov (United States)

    Zelenski, S G

    1977-11-01

    A phytochemical investigation of an alcoholic extract of the petioles of Nelumbo lutea resulted in the identification of the alkaloids N-methylasimilobine, anonaine, and roemerine. The alkaloids nuciferine, armepavine, N-nornuciferine, and N-norarmepavine, previously previously reported in the whole plant, were also identified.

  14. Plant alkaloids of the polymethyleneamine series

    Energy Technology Data Exchange (ETDEWEB)

    Rogoza, Ludmila N; Salakhutdinov, Nariman F; Tolstikov, Genrikh A [N.N. Vorozhtsov Novosibirsk Institute of Organic Chemistry, Siberian Branch of the Russian Academy of Sciences, Novosibirsk (Russian Federation)

    2005-04-30

    The published data on the structures and biological activities of the plant alkaloids of the biogenic polymethyleneamine series, viz., putrescine (1,4-diaminobutane), spermidine (1,8-diamino-4 -azaoctane), and spermine (1,12-diamino-4,9-diazadodecane), are considered and systematised. The structures and biological activities of some synthetic analogues of these alkaloids are also presented.

  15. Piperidine alkaloids: human and food animal teratogens.

    Science.gov (United States)

    Green, Benedict T; Lee, Stephen T; Panter, Kip E; Brown, David R

    2012-06-01

    Piperidine alkaloids are acutely toxic to adult livestock species and produce musculoskeletal deformities in neonatal animals. These teratogenic effects include multiple congenital contracture (MCC) deformities and cleft palate in cattle, pigs, sheep, and goats. Poisonous plants containing teratogenic piperidine alkaloids include poison hemlock (Conium maculatum), lupine (Lupinus spp.), and tobacco (Nicotiana tabacum) [including wild tree tobacco (Nicotiana glauca)]. There is abundant epidemiological evidence in humans that link maternal tobacco use with a high incidence of oral clefting in newborns; this association may be partly attributable to the presence of piperidine alkaloids in tobacco products. In this review, we summarize the evidence for piperidine alkaloids that act as teratogens in livestock, piperidine alkaloid structure-activity relationships and their potential implications for human health.

  16. Isolation and Characterization of Lewis Base Stabilized Monomeric Parent Stibanylboranes.

    Science.gov (United States)

    Marquardt, Christian; Hegen, Oliver; Hautmann, Matthias; Balázs, Gábor; Bodensteiner, Michael; Virovets, Alexander V; Timoshkin, Alexey Y; Scheer, Manfred

    2015-10-26

    The synthesis of the Lewis base stabilized monomeric parent compound of stibanylboranes, "H2 Sb-BH2 ", is reported. Through a salt metathesis route, the silyl-substituted compounds (Me3 Si)2 Sb-BH2 ⋅LB (LB=NMe3 , NHC(Me) ) were synthesized as representatives of derivatives with a Sb-B σ bond. Under very mild conditions, they could be transformed into the target compounds Me3 N⋅H2 B-HSb-BH2 ⋅NMe3 and H2 Sb-BH2 ⋅NHC(Me) , respectively. The products were characterized by X-ray structure analysis, NMR spectroscopy, IR spectroscopy, and mass spectrometry. DFT calculations give further insight into the stability and bonding of these unique compounds.

  17. Light-induced structural changes in a monomeric bacteriophytochrome

    Directory of Open Access Journals (Sweden)

    Heikki Takala

    2016-09-01

    Full Text Available Phytochromes sense red light in plants and various microorganism. Light absorption causes structural changes within the protein, which alter its biochemical activity. Bacterial phytochromes are dimeric proteins, but the functional relevance of this arrangement remains unclear. Here, we use time-resolved X-ray scattering to reveal the solution structural change of a monomeric variant of the photosensory core module of the phytochrome from Deinococcus radiodurans. The data reveal two motions, a bend and a twist of the PHY domain with respect to the chromophore-binding domains. Infrared spectroscopy shows the refolding of the PHY tongue. We conclude that a monomer of the phytochrome photosensory core is sufficient to perform the light-induced structural changes. This implies that allosteric cooperation with the other monomer is not needed for structural activation. The dimeric arrangement may instead be intrinsic to the biochemical output domains of bacterial phytochromes.

  18. Characterization of the Partially Folded Monomeric Intermediate of Creatine Kinase

    Institute of Scientific and Technical Information of China (English)

    朴龙斗; 周海梦

    2002-01-01

    The importance of understanding the protein folding pathway and intermediates is well recognized on the basis of extensive studies of protein folding in vitro and in vivo. Creatine kinase (CK) is a typical model for studying unfolding and refolding of proteins due to several interesting properties. Recent studies on the folding of CK show that its partially folded monomeric intermediate is present kinetically and is stable at equilibrium. The present paper contains 33 References as a mini review to characterize the properties of CK from studies on the CK folding pathway. Characterization of these intermediates is an essential step toward understanding the mechanism of protein folding. Some well-determined schemes are suggested as protein folding models.

  19. Single Molecule Spectroscopy of Monomeric LHCII: Experiment and Theory

    CERN Document Server

    Malý, Pavel; van Grondelle, Rienk; Mančal, Tomáš

    2015-01-01

    We derive approximate equations of motion for excited state dynamics of a multilevel open quantum system weakly interacting with light to describe fluorescence detected single molecule spectra. Based on the Frenkel exciton theory, we construct a model for the chlorophyll part of the LHCII complex of higher plants and its interaction with previously proposed excitation quencher in the form of the lutein molecule Lut 1. The resulting description is valid over a broad range of timescales relevant for single molecule spectroscopy, i.e. from ps to minutes. Validity of these equations is demonstrated by comparing simulations of ensemble and single-molecule spectra of monomeric LHCII with experiments. Using a conformational change of the LHCII protein as a switching mechanism, the intensity and spectral time traces of individual LHCII complexes are simulated, and the experimental statistical distributions are reproduced. Based on our model, it is shown that with reasonable assumptions about its interaction with chlo...

  20. mKikGR, a monomeric photoswitchable fluorescent protein.

    Directory of Open Access Journals (Sweden)

    Satoshi Habuchi

    Full Text Available The recent demonstration and utilization of fluorescent proteins whose fluorescence can be switched on and off has greatly expanded the toolkit of molecular and cell biology. These photoswitchable proteins have facilitated the characterization of specifically tagged molecular species in the cell and have enabled fluorescence imaging of intracellular structures with a resolution far below the classical diffraction limit of light. Applications are limited, however, by the fast photobleaching, slow photoswitching, and oligomerization typical for photoswitchable proteins currently available. Here, we report the molecular cloning and spectroscopic characterization of mKikGR, a monomeric version of the previously reported KikGR that displays high photostability and switching rates. Furthermore, we present single-molecule imaging experiments that demonstrate that individual mKikGR proteins can be localized with a precision of better than 10 nanometers, suggesting their suitability for super-resolution imaging.

  1. Computational design and characterization of a monomeric helical dinuclear metalloprotein.

    Science.gov (United States)

    Calhoun, Jennifer R; Kono, Hidetoshi; Lahr, Steven; Wang, Wei; DeGrado, William F; Saven, Jeffery G

    2003-12-12

    The de novo design of di-iron proteins is an important step towards understanding the diversity of function among this complex family of metalloenzymes. Previous designs of due ferro (DF) proteins have resulted in tetrameric and dimeric four-helix bundles having crystallographically well-defined structures and active-site geometries. Here, the design and characterization of DFsc, a 114 residue monomeric four-helix bundle, is presented. The backbone was modeled using previous oligomeric structures and appropriate inter-helical turns. The identities of 26 residues were predetermined, including the primary and secondary ligands in the active site, residues involved in active site accessibility, and the gamma beta gamma beta turn between helices 2 and 3. The remaining 88 amino acid residues were determined using statistical computer aided design, which is based upon a recent statistical theory of protein sequences. Rather than sampling sequences, the theory directly provides the site-specific amino acid probabilities, which are then used to guide sequence design. The resulting sequence (DFsc) expresses well in Escherichia coli and is highly soluble. Sedimentation studies confirm that the protein is monomeric in solution. Circular dichroism spectra are consistent with the helical content of the target structure. The protein is structured in both the apo and the holo forms, with the metal-bound form exhibiting increased stability. DFsc stoichiometrically binds a variety of divalent metal ions, including Zn(II), Co(II), Fe(II), and Mn(II), with micromolar affinities. 15N HSQC NMR spectra of both the apo and Zn(II) proteins reveal excellent dispersion with evidence of a significant structural change upon metal binding. DFsc is then a realization of complete de novo design, where backbone structure, activity, and sequence are specified in the design process.

  2. Genetic variation in alkaloid accumulation in leaves of Nicotiana

    Institute of Scientific and Technical Information of China (English)

    Bo SUN; Fen ZHANG; Guo-jun ZHOU; Guo-hai CHU; Fang-fang HUANG; Qiao-mei WANG; Li-feng JIN; Fu-cheng LIN; Jun YANG

    2013-01-01

    Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such as nornicotine and myosmine, have adverse effects on human health. To reduce the content of harmful alkaloids in tobacco leaves through conventional breeding, a genetic study of the alkaloid variation among different genotypes is required. In this study, alkaloid profiles in leaves of five Nicotiana tabacum cultivars and Nicotiana tomentosiformis were investigated. Six alkaloids were identified from al six genotypes via gas chromatograph-mass spectrometry (GC-MS). Significant differences in alkaloid content were ob-served both among different leaf positions and among cultivars. The contents of nornicotine and myosmine were positively and significantly correlated (R2=0.881), and were also separated from those of other alkaloids by clustering. Thus, the genotype plays a major role in alkaloid accumulation, indicating a high potential for manipulation of alkaloid content through traditional breeding.

  3. Genetic variation in alkaloid accumulation in leaves of Nicotiana.

    Science.gov (United States)

    Sun, Bo; Zhang, Fen; Zhou, Guo-jun; Chu, Guo-hai; Huang, Fang-fang; Wang, Qiao-mei; Jin, Li-feng; Lin, Fu-cheng; Yang, Jun

    2013-12-01

    Alkaloids are plant secondary metabolites that are widely distributed in Nicotiana species and contribute greatly to the quality of tobacco leaves. Some alkaloids, such as nornicotine and myosmine, have adverse effects on human health. To reduce the content of harmful alkaloids in tobacco leaves through conventional breeding, a genetic study of the alkaloid variation among different genotypes is required. In this study, alkaloid profiles in leaves of five Nicotiana tabacum cultivars and Nicotiana tomentosiformis were investigated. Six alkaloids were identified from all six genotypes via gas chromatograph-mass spectrometry (GC-MS). Significant differences in alkaloid content were observed both among different leaf positions and among cultivars. The contents of nornicotine and myosmine were positively and significantly correlated (R(2)=0.881), and were also separated from those of other alkaloids by clustering. Thus, the genotype plays a major role in alkaloid accumulation, indicating a high potential for manipulation of alkaloid content through traditional breeding.

  4. Comparative Study of Alkaloid Pattern of Four Bulgarian Fumaria species.

    Science.gov (United States)

    Doncheva, Tsvetelina; Yordanova, Gabriela; Vutov, Vassil; Kostova, Nadezhda; Philipov, Stefan

    2016-02-01

    The alkaloid pattern of four Fumaria species (Fumaria kralikii, Fumaria rostellata, Fumaria schleicherii, Fumaria thureii) growing in Bulgaria was investigated by GC-MS and twenty isoquinoline alkaloids were determined. Phytochemical investigation of the alkaloid composition on Fumaria thuretii Boiss was made for the first time. The alkaloid profile of the species was compared at two levels, between different species and within two species from different habitats. Two chemotypical groups, based on the types of isoquinoline alkaloids were suggested. To group A belong species F. kralikii, F. rostellata (F. r. 1) and F. thuretii containing more than 50% spirobenzylisoquinoline alkaloids of the crude alkaloid mixtures. To group B belong species F. rostellata (F. r. 2) and F. schleicherii containing more than 40% protopine alkaloids and relatively high percentage phthaldeisoquinoline alkaloids (11-19%). In group A phthaldeisoquinoline alkaloids were not detected.

  5. Isoquinoline and isoindole alkaloids from Menispermum dauricum.

    Science.gov (United States)

    Zhang, Xiaoqi; Ye, Wencai; Zhao, Shouxun; Che, Chun-Tao

    2004-04-01

    Three isoquinoline alkaloids and an isoindole alkaloid, along with eight known compounds, were isolated from the roots of Menispermum dauricum (Menispermacese). The alkaloids were characterized as 7-hydroxy-6-methoxy-1(2H)-isoquinolinone, 6,7-dimethoxy-N-methyl-3,4-dioxo-1(2H)-isoquinolinone, 1-(4-hydroxybenzoyl)-7-hydroxy-6-methoxy-isoquinoline and 6-hydroxy-5-methoxy-N-methylphthalimide, on the basis of spectral evidence including 1D- and 2D-NMR and MS analyses.

  6. Polycyclic Guanidine Alkaloids from Poecilosclerida Marine Sponges.

    Science.gov (United States)

    Sfecci, Estelle; Lacour, Thierry; Amade, Philippe; Mehiri, Mohamed

    2016-04-09

    Sessile marine sponges provide an abundance of unique and diversified scaffolds. In particular, marine guanidine alkaloids display a very wide range of biological applications. A large number of cyclic guanidine alkaloids, including crambines, crambescins, crambescidins, batzelladines or netamins have been isolated from Poecilosclerida marine sponges. In this review, we will explore the chemodiversity of tri- and pentacyclic guanidine alkaloids. NMR and MS data tools will also be provided, and an overview of the wide range of bioactivities of crambescidins and batzelladines derivatives will be given.

  7. Marine Pyridoacridine Alkaloids: Biosynthesis and Biological Activities.

    Science.gov (United States)

    Ibrahim, Sabrin R M; Mohamed, Gamal A

    2016-01-01

    Pyridoacridines are a class of strictly marine-derived alkaloids that constitute one of the largest chemical families of marine alkaloids. During the last few years, both natural pyridoacridines and their analogues have constituted excellent targets for synthetic works. They have been the subject of intense study due to their significant biological activities; cytotoxic, antibacterial, antifungal, antiviral, insecticidal, anti-HIV, and anti-parasitic activities. In the present review, 95 pyridoacridine alkaloids isolated from marine organisms are discussed in term of their occurrence, biosynthesis, biological activities, and structural assignment.

  8. Norditerpenoid Alkaloids from Aconitum spicatum Stapf

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To search for pharmacologically and structurally interesting substances from traditional Chinese medicines,we investigated the chemical compounds of Aconitum spicatum Stapf. Two new norditerpenoid alkaloids,namely spicatine A (compound 1) and spicatine B (compound 2), as well as 11 known norditerpenoid alkaloids were isolated from the CHCl3 portion of the 90% ethanol extract of the roots of A. spicatum. The structures of the alkaloids were characterized on the basis of their spectral data, One of the isolated compounds showed significant cytotoxic activities (IC50 values < 200 μmol/L) against the HL-60 cell line.

  9. Racemic alkaloids from the fungus Ganoderma cochlear.

    Science.gov (United States)

    Wang, Xin-Long; Dou, Man; Luo, Qi; Cheng, Li-Zhi; Yan, Yong-Ming; Li, Rong-Tao; Cheng, Yong-Xian

    2017-01-01

    Seven pairs of new alkaloid enantiomers, ganocochlearines C-I (1, 3-8), and three pairs of known alkaloids were isolated from the fruiting bodies of Ganoderma cochlear. The chemical structures of new compounds were elucidated on the basis of 1D and 2D NMR data. The absolute configurations of compounds 1, 3-10 were assigned by ECD calculations. Biological activities of these isolates against renal fibrosis were accessed in rat normal or diseased renal interstitial fibroblast cells. Importantly, the plausible biosynthetic pathway for this class of alkaloids was originally proposed.

  10. OVIPOSITION AND OVICIDAL ACTIVITIES OF ALKALOIDAL ...

    African Journals Online (AJOL)

    ... moderate ovicidal activity but inflict delayed effects such as high larval and low pupal and adult mortality. ... Key Words: Murraya koenigii; Rutaceae; alkaloidal extract; oviposition; ovicidal; Culex quinquefasciatus; Culex tritaeniorhynchus.

  11. Antiprotozoal and antioxidant alkaloids from Alternanthera littoralis.

    Science.gov (United States)

    Koolen, Hector H F; Pral, Elizabeth M F; Alfieri, Silvia C; Marinho, Jane V N; Serain, Alessandra F; Hernández-Tasco, Alvaro J; Andreazza, Nathalia L; Salvador, Marcos J

    2017-02-01

    Five alkaloids, in addition to hydroxytyrosol and uridine, were isolated from aerial parts of Alternanthera littoralis P. Beauv. Among the isolated compounds, alternamide A was an unusual tricyclic alkaloid with a bridged benzoazepine core. All isolated alkaloids have a catechol moiety, indicating a possible common biosynthetic route. Their structures were established by 1D and 2D NMR spectroscopy in combination with extensive tandem MS experiments by collisional induced dissociation (CID). The antiprotozoal activity of the isolated compounds was assayed against trypomastigote forms of Trypanosoma cruzi and amastigotes of Leishmania amazonensis. Alternamine A was the most active compound, reducing markedly the viability of both parasites. Antioxidant capacities evaluated by ORACFL assay showed that the isolated alkaloids (mainly alternamide B) contributed to the high activity recorded for the ethanolic crude extract; possibly, the catechol moiety present in all structures plays a central role in this result.

  12. Anxiolytic Activity of Diterpene Alkaloid Songorine.

    Science.gov (United States)

    Nesterova, Yu V; Povet'eva, T N; Suslov, N I; Shults, E E; Ziuz'kov, G N; Aksinenko, S G; Afanas'eva, O G; Krapivin, A V; Kharina, T G

    2015-09-01

    Antianxiety action of diterpene alkaloid songorine was studied using Vogel conflict test. Songorine in a dose of 0.25 mg/kg demonstrated high anxiolytic activity comparable to that of phenazepam and produced no sedative effect.

  13. Steroidal alkaloid toxicity to fish embryos.

    Science.gov (United States)

    Crawford, L; Kocan, R M

    1993-02-01

    Embryos of two species of fish were evaluated for their suitability as model systems for steroidal alkaloid toxicity, the Japanese rice fish, medaka (Oryzius latipes) and the rainbow trout (Oncorhynchus mykiss). Additionally, the equine neurotoxic sesquiterpene lactone repin, was also tested. A PROBIT program was used to evaluate the EC1, EC50 and EC99 as well as the associated confidence limits. The steroidal alkaloids tested were the Solanum potato glycoalkaloids alpha-chaconine, alpha-solanine, the aglyclones solanidine and solasodine and the Veratrum alkaloid, jervine. Embryo mortality, likely due to structural or functional abnormalities in the early development stages of the embryo, were the only response observed in both species. The rainbow trout exhibited a toxic response to chaconine, solasidine, repin and solanine but the medaka embryos were only affected by the compounds, chaconine and solanine. Rainbow trout may indeed serve as a good lower vertebrate model for studying the toxicity of steroidal alkaloids.

  14. Alkaloids from Fissistigma latifolium (Dunal Merr.

    Directory of Open Access Journals (Sweden)

    Asmah Alias

    2010-06-01

    Full Text Available A phytochemical study of the bark of Fissistigma latifolium (Annonaceae yielded a new aporphine alkaloid, (--N-methylguattescidine (1, and eight known alkaloids: liriodenine (2, oxoxylopine (3, (--asimilobine (4, dimethyltryptamine (5, (--remerine (6, (--anonaine (7, columbamine (8 and lysicamine (9. The compounds were isolated using various chromatographic methods and structural elucidation was accomplished by means of spectroscopic methods, notably 1D-NMR (1H, 13C, DEPT, 2D-NMR (COSY, HMQC, HMBC, UV, IR and MS.

  15. Polycyclic alkaloids via transannular Mannich reactions

    DEFF Research Database (Denmark)

    Vital, Paulo; Hosseini, Masood; Shanmugham, M. S.

    2009-01-01

    The tricyclic compound 13, representing the framework of the cylindricine 4 and lepadiformine 5 alkaloids, was prepared in a single operation via the first example of a transannular Mannich reaction involving a macrocyclic diketoamine 12.......The tricyclic compound 13, representing the framework of the cylindricine 4 and lepadiformine 5 alkaloids, was prepared in a single operation via the first example of a transannular Mannich reaction involving a macrocyclic diketoamine 12....

  16. Two new diterpene alkaloids from Delphinium chrysotrichum

    Institute of Scientific and Technical Information of China (English)

    Yang Qing He; Xiao Mei Wei; Yi Li Han; Li Ming Gao

    2007-01-01

    Chemical investigation on the ethanol extract from the whole plants of Delphinium chrysotrichum resulted in the isolation of two new diterpene alkaloids named delphatisine A (1) and delphatisine B (2), respectively. The structures of the new compounds were deduced on the basis of their spectral data (IR, HREIMS, EIMS, 1D, 2D-NMR). This is the first report on the isolation of diterpenoid alkaloids from the D. Chrysotrichum.

  17. Properties of monomeric paramyosin using a transient electric birefringence techniques.

    Science.gov (United States)

    DeLaney, D; Krause, S

    1976-01-01

    Paramyosin samples obtained from the chowder clam, Mercenaria mercenaria, by different extraction techniques were studied using transient electric birefringence techniques. The protein remain monomeric (unaggregated) in 1 mM buffer solution at pH 3.1 to 3.8 and near pH 10. At pH 3.2, the molecules obtained by different extraction techniques exhibit rotational diffusion constants that indicate a 5% difference in length between them, with the probable native form of paramyosin being the longer species. This difference in rotational diffusion constant disappears at higher pH, and, in addition, a large difference in dipole moment between the molecules observed at pH 3.2 also disappears at high pH. These results are used to hypothesize that the rodlike native paramyosin molecules have one or two partly flexible portions on their ends; at one end of each molecule this portion probably contains excess basic amino acids which are charged at low pH to account for the higher dipole moment of this form of paramyosin at these low pH values. At pH 3.2, these portions of the macromolecule are not flexible and act as stiff parts of the rodlike molecules, but they gradually become flexible at higher pH. Possible mechanisms for this change in flexibility are discussed.

  18. Labeling Monomeric Insulin with Renal-Clearable Luminescent Gold Nanoparticles.

    Science.gov (United States)

    Vinluan, Rodrigo D; Yu, Mengxiao; Gannaway, Melissa; Sullins, Justin; Xu, Jing; Zheng, Jie

    2015-12-16

    In the native physiological environment, inorganic nanoparticles (NPs) often induce nonspecific protein adsorption, which could significantly alter the function of the proteins they labeled. As a result, small fluorescent dyes are still widely used in the imaging of proteins in animals due to their minimal interference with protein function. Here, we used monomeric insulin as a model and compared its bioactivity before and after labeling with renal-clearable near-infrared-emitting gold NPs. These NPs were chosen because they have high resistance to serum protein adsorption and low nonspecific accumulation. We have found that a 1:1 insulin-NP ratio can be achieved, where the insulin-NPs show minimal serum protein binding with fully retained bioactivity comparable to that of unlabeled insulin. These results show a proof of concept that renal-clearable NPs can behave like small molecules in protein labeling without changing the individual protein's function, laying down a foundation for in vivo tracking of proteins with multimodality imaging techniques.

  19. Visual identification of alkaloids in some medicinal plants: common alkaloid reagents versus bromocresol green

    Directory of Open Access Journals (Sweden)

    Shamsa F, Esfahani HR, Gamooshi RA

    2008-07-01

    Full Text Available "n Normal 0 false false false MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Times New Roman"; mso-ansi-language:#0400; mso-fareast-language:#0400; mso-bidi-language:#0400;} Background: Alkaloids are a group of nitrogenous compounds with potential effects on the physiological behavior of human and animals. Some of these compounds are considered important drugs in modern medicine, such as atropine and morphine. Plants are considered the most important source of alkaloids. Therefore, investigating the presence of alkaloids in different plants is very important. Usually, alkaloids in plants are identified by methods such as those of Dragendorf, Wagner and Meyer, among others, which require milligrams of alkaloids for identification. In the present study, a fast and sensitive procedure for detecting of alkaloids in plants is presented.   "n"nMethods: Twelve dried plants samples were investigated for the presence alkaloids. After extracting the total alkaloid into methanol using a Soxhlet extractor, a few milligrams of the extract was transferred to a separatory funnel, buffered to pH 4.7, the bromocresol green (BCG solution (10-4 M was added, mixed and extracted with CHCl3 until a yellow color was observed in the CHCl3 layer, indicating the presence of the alkaloid. The crude extracts were also investigated by the standard methods of Dragendorf, Wagner and Meyer for the presence of alkaloids.   "n"nResults: Investigation of the 12 plant samples for the presence of alkaloids by the standard reagents of Dragendorf, Wagner, and Meyer showed that only Camelia sinensis (flowers, Echium amoenum Fisch & Mey (flowers, and Stachys (aerial parts are devoid

  20. Substrate-Induced Dimerization of Engineered Monomeric Variants of Triosephosphate Isomerase from Trichomonas vaginalis.

    Directory of Open Access Journals (Sweden)

    Samuel Lara-Gonzalez

    Full Text Available The dimeric nature of triosephosphate isomerases (TIMs is maintained by an extensive surface area interface of more than 1600 Å2. TIMs from Trichomonas vaginalis (TvTIM are held in their dimeric state by two mechanisms: a ball and socket interaction of residue 45 of one subunit that fits into the hydrophobic pocket of the complementary subunit and by swapping of loop 3 between subunits. TvTIMs differ from other TIMs in their unfolding energetics. In TvTIMs the energy necessary to unfold a monomer is greater than the energy necessary to dissociate the dimer. Herein we found that the character of residue I45 controls the dimer-monomer equilibrium in TvTIMs. Unfolding experiments employing monomeric and dimeric mutants led us to conclude that dimeric TvTIMs unfold following a four state model denaturation process whereas monomeric TvTIMs follow a three state model. In contrast to other monomeric TIMs, monomeric variants of TvTIM1 are stable and unexpectedly one of them (I45A is only 29-fold less active than wild-type TvTIM1. The high enzymatic activity of monomeric TvTIMs contrast with the marginal catalytic activity of diverse monomeric TIMs variants. The stability of the monomeric variants of TvTIM1 and the use of cross-linking and analytical ultracentrifugation experiments permit us to understand the differences between the catalytic activities of TvTIMs and other marginally active monomeric TIMs. As TvTIMs do not unfold upon dimer dissociation, herein we found that the high enzymatic activity of monomeric TvTIM variants is explained by the formation of catalytic dimeric competent species assisted by substrate binding.

  1. SGCC successfully developed large-capacity sodium-sulfur monomeric battery

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Through many years' cooperation,SGCC and Shanghai Silicate Research Institute of Chinese Academy of Science successfully developed 650 ampere-hours capacity sodium-sulfur monomeric storage battery with the independent intellectual property right

  2. Amphiphile dependency of the monomeric and dimeric forms of acetylcholinesterase from human erythrocyte membrane.

    Science.gov (United States)

    Ott, P; Brodbeck, U

    1984-08-08

    Human erythrocyte membrane-bound acetylcholinesterase was converted to a monomeric species by treatment of ghosts with 2-mercaptoethanol and iodoacetic acid. After solubilization with Triton X-100, the reduced and alkylated enzyme was partially purified by affinity chromatography and separated from residual dimeric enzyme by sucrose density gradient centrifugation in a zonal rotor. Monomeric and dimeric acetylcholinesterase showed full enzymatic activity in presence of Triton X-100 whereas in the absence of detergent, activity was decreased to approx. 20% and 15%, respectively. Preformed egg phosphatidylcholine vesicles fully sustained activity of the monomeric species whereas the dimer was only 80% active. The results suggest that a dimeric structure is not required for manifestation of amphiphile dependency of membrane-bound acetylcholinesterase from human erythrocytes. Furthermore, monomeric enzyme appears to be more easily inserted into phospholipid bilayers than the dimeric species.

  3. Two New C19-Diterpenoid Alkaloids from Delphinium davidii Franch.

    Institute of Scientific and Technical Information of China (English)

    Xiao Xia LIANG; Dong Lin CHEN; Feng Peng WANG

    2006-01-01

    Two new C19-diterpenoid alkaloids, davidisines A (1) and B (2) along with thirteen known alkaloids were isolated from the whole herb of Delphinium davidii Franch. Their structures were established by spectral methods, especially 2D NMR techniques.

  4. Biosynthesis of Monoterpenoid Indole Alkaloid Ajmaline Catalyzed by Novel Reductases

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ Introduction One of the major root alkaloids of the Indian medicinal plant Rauvolfia serpenlina Benth. Ex Kurz is named ajmaline. The enzymatic biosynthesisof this alkaloid has been studied for a long time by our group[1].

  5. Biological activity of alkaloids from Solanum dulcamara L.

    Science.gov (United States)

    Kumar, Padma; Sharma, Bindu; Bakshi, Nidhi

    2009-01-01

    Alkaloids are well known for their antimicrobial activity. Though all natural alkaloids come from plants, not all plants produce alkaloids. Plants of the Solanaceae family are known for their high alkaloid content. Alkaloids are found in all plant parts like roots, stems, leaves, flowers, fruits and seeds. In the present study, those plant parts of Solanum dulcamara were selected which have been reported to produce a high content of a specific alkaloid: solanine (from unripe fruits), solasodine (from flowers) and beta-solamarine (from roots). These alkaloids were extracted from various parts of S. dulcamara by well-established methods and were screened for their antibacterial activity. Human pathogenic bacteria, viz., Enterobacter aerogenes, Escherichia coli, Staphylococcus aureus, were selected for the study. All three alkaloids inhibited the growth of E. coli and S. aureus. However, no significant activity was observed against E. aerogenes. Minimum inhibitory concentration and minimum bactericidal concentration were also evaluated.

  6. An Acetylenic Alkaloid from the Calcareous Sponge Leucetta sp.

    OpenAIRE

    Nicole J de Voogd; Idam Hermawan; Junichi Tanaka

    2011-01-01

    A new acetylenic alkaloid was isolated from the sponge Leucetta sp. The structure was established by analyzing spectroscopic data. The alkaloid showed cytotoxicity IC50 2.5 mg/mL against NBT-T2 cells.

  7. The alkaloids of the madangamine group.

    Science.gov (United States)

    Amat, Mercedes; Pérez, Maria; Ballette, Roberto; Proto, Stefano; Bosch, Joan

    2015-01-01

    This chapter is focused on madangamines, a small group of complex diamine alkaloids isolated from marine sponges of the order Haplosclerida, and covers their isolation, characterization, biogenesis, biological activity, and synthesis. Structurally, madangamines are pentacyclic alkaloids with an unprecedented skeletal type, characterized by a common diazatricyclic core and two peripheral macrocyclic rings. The isolation of these alkaloids from Xestospongia ingens (madangamines A-E) and Pachychalina alcaloidifera (madangamine F) is described in detail. Physical and complete spectroscopic 1H and 13C NMR data are included. The proposed biogenesis of madangamines from ammonia, a functionalized three-carbon unit, and saturated or unsaturated linear long-chain dialdehydes, via partially reduced bis-alkylpyridine macrocycles, is discussed. The synthesis of alkaloids of the madangamine group has been little explored, with only one total synthesis reported so far, that of (+)-madangamine D. This review also describes several model synthetic approaches to the diazatricyclic ABC core of these alkaloids, as well as model studies on the construction of the (Z,Z)-unsaturated 11-membered E macrocycle common to madangamines A-E, the 13- and 14-membered D rings of madangamines C-E, and the all-cis-triunsaturated 15-membered D ring of madangamine A. Some members of this group have shown significant in vitro cytotoxicity against a number of cancer cell lines.

  8. Hemlock alkaloids from Socrates to poison aloes.

    Science.gov (United States)

    Reynolds, Tom

    2005-06-01

    Hemlock (Conium maculatum L. Umbelliferae) has long been known as a poisonous plant. Toxicity is due to a group of piperidine alkaloids of which the representative members are coniine and gamma-coniceine. The latter is the more toxic and is the first formed biosynthetically. Its levels in relation to coniine vary widely according to environmental conditions and to provenance of the plants. Surprisingly, these piperidine alkaloids have turned up in quite unrelated species in the monocotyledons as well as the dicotyledons. Aloes, for instance, important medicinal plants, are not regarded as poisonous although some species are very bitter. Nevertheless a small number of mostly local species contain the alkaloids, especially gamma-coniceine and there have been records of human poisoning. The compounds are recognized by their characteristic mousy smell. Both acute and chronic symptoms have been described. The compounds are neurotoxins and death results from respiratory failure, recalling the effects of curare. Chronic non-lethal ingestion by pregnant livestock leads to foetal malformation. Both acute and chronic toxicity are seen with stock in damp meadows and have been recorded as problems especially in North America. The alkaloids derive biosynthetically from acetate units via the polyketide pathway in contrast to other piperidine alkaloids which derive from lysine.

  9. TOXIC PYRROLIZIDINE ALKALOIDS OF ECHIUM AMOENUM FISCH. & MEY.

    OpenAIRE

    2006-01-01

    Toxic pyrrolizidine alkaloids are present in some species of Echium (Boraginaceae). In this study petals of Echium amoenum Fisch. & Mey. (Gol-e-Gavzaban) as a popular herbal medicine in Iran, were investigated for pyrrolizidine alkaloids (PAs). The alkaloids were separated and purified by preparative TLC and characterized by IR, one and two dimensional 1H and 13C-NMR and Mass spectroscopy. Four toxic alkaloids namely: echimidine I, echimidine isomer II, 7-angeloyl retronecine III and 7-ti...

  10. Simulation of the type of coralin alkaloid-DNA binding

    Science.gov (United States)

    Kulikov, K. G.; Koshlan, T. V.

    2015-05-01

    Interaction between a synthesized coralin protoberberine alkaloid and the DNA double helix of the calf's thymus in a salt solution is studied by optical absorption spectroscopy and spectropolarimetry. The dependence of the spectral characteristics of the alkaloid on a ratio between the DNA base pair concentration and the alkaloid molecule concentration is considered. The parameters of bonds between the coralin alkaloid and the DNA double helix are determined using modified McGhee-von Hippel equations.

  11. [Study on optimum extraction conditions of alkaloids from Pinellia ternate].

    Science.gov (United States)

    Zeng, Jianhong; Peng, Zhengsong; Mao, Zicheng; Wei, Shuhong

    2003-05-01

    The optimum extraction conditions of alkaloids from Pinellia ternate (Thunb.) Breit were studied by orthogonal test. The results showed that the highest extraction rate of the alkaloids could be obtained by smashing the material in 60 (sieve number) of fragmentation and socking the material in 2.575 mol/L ammonia water, extracting alkaloids with 18 times as much chlorolform at room temperature for 25 hours. The highest extraction rate of alkaloids was 0.0817%.

  12. The Double-Bond Configuration of Corynanthean Alkaloids and Its Impact on Monoterpenoid Indole Alkaloid Biosynthesis.

    Science.gov (United States)

    Eckermann, Ruben; Gaich, Tanja

    2016-04-11

    Experimental evidence is provided for the coherence of the double-bond geometry and the occurrence of "secondary cyclizations" in the biosynthesis of monoterpenoid indole alkaloids. Biosynthetically, akuammiline, C-mavacurine, and Strychnos alkaloids are proposed to be derived from the corynanthean alkaloid geissoschizine, a key intermediate in the biosynthetic pathway of these monoterpenoid indole alkaloids. This process occurs by so-called "secondary cyclizations" from geissoschizine or its derivatives. Although corynanthean alkaloids like geissoschizine incorporate E or Z double bonds located at C19-C20, the alkaloids downstream in the biosynthesis exclusively exhibit the E double bond. This study shows that secondary cyclizations preferentially occur with the E isomer of geissoschizine or its derivatives. This is attributed to the flexibility of the quinolizidine system of the corynanthean alkaloids, which can adopt a cis or trans conformation. For the secondary cyclization to take place, the cis-quinolizidine conformation is required. Experimental evidence supports the hypothesis that the E double bond of geissoschizine induces the cis conformation, whereas the Z double bond induces the trans conformation, which prohibits secondary cyclization of the Z compounds.

  13. Two new alkaloids of the crinane series from Pancratium sickenbergeri.

    Science.gov (United States)

    Abou-Donia, Amina H; Amer, Masouda E; Darwish, Fikria A; Kassem, Fahima F; Hammoda, Hala M; Abdel-Kader, Maged S; Zhou, Bing-Nan; Kingston, David G I

    2002-04-01

    Two new alkaloids; ent-6alpha/6beta-hydroxybuphanisine, (-)-8-demethylmaritidine and seven known alkaloids were isolated from Pancratium sickenbergeri grown in Egypt. Three of the known alkaloids were tested in the NCI cytotoxicity screen, but were found to be inactive.

  14. Pancratium canariense as an important source of amaryllidaceae alkaloids.

    Science.gov (United States)

    Cedrón, Juan C; Oberti, Juan C; Estévez-Braun, Ana; Ravelo, Angel G; Del Arco-Aguilar, Marcelino; López, Matías

    2009-01-01

    Four new alkaloids (1-4) have been isolated from a methanolic extract of bulbs of Pancratium canariense, together with 12 known alkaloids (5-16). The structures of the new alkaloids were determined by extensive 1D and 2D NMR spectroscopic studies and X-ray diffraction.

  15. 21 CFR 119.1 - Dietary supplements containing ephedrine alkaloids.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Dietary supplements containing ephedrine alkaloids... UNREASONABLE RISK § 119.1 Dietary supplements containing ephedrine alkaloids. Dietary supplements containing ephedrine alkaloids present an unreasonable risk of illness or injury under conditions of use recommended...

  16. An Unusual Pentacyclic Dinitrogenous Alkaloid from Galanthus gracilis

    OpenAIRE

    ÜNVER, Nehir; KAYA, G. İrem

    2005-01-01

    A minor alkaloid, namely gracilamine, was isolated from Galanthus gracilis. This was the first example of a pentacyclic dinitrogenous alkaloid isolated from a member of Amaryllidaceae. The structure of this alkaloid was elucidated by means of comprehensive spectroscopic methods (1D and 2D NMR, MS, UV, IR).

  17. Two New Alkaloids from Narcissus serotinus L.

    Directory of Open Access Journals (Sweden)

    Francesc Viladomat

    2010-10-01

    Full Text Available The Amaryllidaceae family is well known for the presence of an exclusive group of alkaloids with a wide range of biological activities. Narcissus serotinus L. is a plant belonging to this family and its geographical distribution is mainly located along the Mediterranean coast. In the present work, specimens collected near Casablanca (Morocco were used to study the alkaloid content of this species. Starting with 350 g of the whole plant we used standard extraction and purification procedures to obtain fractions and compounds for GC-MS and NMR analysis. As well as five known alkaloids, we isolated two new compounds: 1-O-(3´-acetoxybutanoyllycorine and narseronine. The latter has been previously published, but with an erroneous structure.

  18. Aporphine alkaloids from Ocotea macrophylla (Lauraceae

    Directory of Open Access Journals (Sweden)

    Ludy Cristina Pabon

    2010-01-01

    Full Text Available Four aporphine alkaloids from the wood of Ocotea macrophylla (Lauraceae were isolated and characterized as (S-3-methoxy-nordomesticine (1, (S-N-ethoxycarbonyl-3-methoxy-nordomesticine (2, (S-N-formyl-3-methoxy-nordomesticine (3 and (S-N-methoxycarbonyl-3-methoxy-nordomesticine (4; alkaloids 2-4 are being report for the first time. The structure the isolated compounds were determined based on their spectral data and by comparison of their spectral data with values described in literature. The alkaloid fraction and compound 1 showed antifungal activity against Fusarium oxysporum f. sp. lycopersici and also compound 1 showed antimicrobial activity towards Staphylococcus aureus, Enterococcus faecalis as well.

  19. Aporphine alkaloids from Ocotea macrophylla (Lauraceae)

    Energy Technology Data Exchange (ETDEWEB)

    Pabon, Ludy Cristina; Cuca, Luis Enrique, E-mail: lcpabonb@unal.edu.c [Universidad Nacional de Bogota (Colombia). Facultad de Ciencias. Dept. de Quimica

    2010-07-01

    Four aporphine alkaloids from the wood of Ocotea macrophylla (Lauraceae) were isolated and characterized as (S)-3-methoxy-nordomesticine (1), (S)-N-ethoxycarbonyl-3-methoxy-nordomesticine (2), (S)-N-formyl-3-methoxy-nordomesticine (3) and (S)-N-methoxycarbonyl-3-methoxy-nordomesticine (4); alkaloids 2-4 are being report for the first time. The structure the isolated compounds were determined based on their spectral data and by comparison of their spectral data with values described in literature. The alkaloid fraction and compound 1 showed antifungal activity against Fusarium oxysporum f. sp. lycopersici and also compound 1 showed antimicrobial activity towards Staphylococcus aureus, Enterococcus faecalis as well. (author)

  20. An efficient synthesis of loline alkaloids

    Science.gov (United States)

    Cakmak, Mesut; Mayer, Peter; Trauner, Dirk

    2011-07-01

    Loline (1) is a small alkaloid that, in spite of its simple-looking structure, has posed surprising challenges to synthetic chemists. It has been known for more than a century and has been the subject of extensive biological investigations, but only two total syntheses have been achieved to date. Here, we report an asymmetric total synthesis of loline that, with less then ten steps, is remarkably short. Our synthesis incorporates a Sharpless epoxidation, a Grubbs olefin metathesis and an unprecedented transannular aminobromination, which converts an eight-membered cyclic carbamate into a bromopyrrolizidine. The synthesis is marked by a high degree of chemo- and stereoselectivity and gives access to several members of the loline alkaloid family. It delivers sufficient material to support a programme aimed at studying the complex interactions between plants, fungi, insects and bacteria brokered by loline alkaloids.

  1. Antiprotozoal alkaloids from Psychotria prunifolia (Kunth) Steyerm

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Lucilia; Oliveira, Cecilia M.A. de; Faria, Emiret O.; Ribeiro, Laryssa C.; Carvalho, Brenda G., E-mail: lucilia@quimica.ufg.br [Instituto de Quimica, Universidade Federal de Goias, Campus II, Samambaia, Goiania, GO (Brazil); Silva, Cleuza C. da; Santin, Silvana M.O. [Departamento de Quimica, Universidade Estadual de Maringa, Maringa, PR (Brazil); Schuque, Ivania T.A.; Nakamura, Celso V.; Britta, Elisandra A.; Miranda, Nathielle [Departamento de Farmacia e Farmacologia, Universidade Estadual de Maringa, PR (Brazil); Iglesias, Amadeu H. [Waters Technologies do Brasil LTDA, Barueri, SP (Brazil); Delprete, Piero G. [VHerbier de Guyane, Institut de Recherche pour le Developpement (IRD), UMR AMAP, French Guiana (France)

    2012-07-01

    The continuity of the phyto chemical study of crude extracts of P. prunifolia's roots and branches led to the isolation of five indole-{beta}-carboline alkaloids. Among them, the 10-hydroxy-iso-deppeaninol and N-oxide-10-hydroxy-antirhine derivatives are described here for the first time. The structures were achieved through 1D and 2D NMR, IR and HRMS analyses. The branches and roots crude extracts and the alkaloids 14-oxoprunifoleine and strictosamide showed selective activity against L. amazonensis, with IC{sub 50} values of 16.0 and 40.7 {mu}g per mL, respectively. (author)

  2. Total Synthesis of the Zoanthamine Alkaloid

    Institute of Scientific and Technical Information of China (English)

    M. Miyashita

    2005-01-01

    @@ 1Introduction The zoanthamine alkaloids, a type of heptacyclic marine alkaloid isolated from colonial zoanthids of the genus Zoanthus sp., have attracted much attention from a wide area of science, because of their distinctive biological and pharmacological properties as well as their chemical structures with stereochemical complexity.Namely, norzoanthamine (1)[1] can suppress the loss of bone weight and strength in ovariectomized mice and has been considered a promising candidate for an antiosteoporotic drug[1], whereas zoanthamine (2)[2] has exhibited potent inhibitory activity toward phorbol myristate-induced inflammation in addition to powerful analgesic effects[2]. See Fig. 1.

  3. Chemotaxonomy and geographical distribution of tropane alkaloids.

    Science.gov (United States)

    Griffin, W J; Lin, G D

    2000-03-01

    This review illustrates the distribution of tropane alkaloids within the families Solanaceae, Erythroxylaceae, Proteaceae, Euphorbiaceae, Rhizophoraceae, Convolvulaceae and Cruciferae. Whereas tropane alkaloids are characteristic of the genera Datura, Brugmansia (tree datura) and Duboisia of the Solanaceae, the distribution is more widespread with novel tropane derivatives in families not traditionally associated with these bases. The chemical nature of more recently discovered water-soluble calystegines and the di- and trimeric forms from the Convolvulaceae (e.g. schizanthines from Schizanthus spp.), truxillines from Bolivian coca leaves and moonines of Erythroxylum moonii are highlighted. Where possible and appropriate, links between the phytochemistry and taxonomy are discussed.

  4. A monomeric variant of insulin degrading enzyme (IDE loses its regulatory properties.

    Directory of Open Access Journals (Sweden)

    Eun Suk Song

    Full Text Available BACKGROUND: Insulin degrading enzyme (IDE is a key enzyme in the metabolism of both insulin and amyloid beta peptides. IDE is unique in that it is subject to allosteric activation which is hypothesized to occur through an oligomeric structure. METHODOLOGY/PRINCIPAL FINDINGS: IDE is known to exist as an equilibrium mixture of monomers, dimers, and higher oligomers, with the dimer being the predominant form. Based on the crystal structure of IDE we deleted the putative dimer interface in the C-terminal region, which resulted in a monomeric variant. Monomeric IDE retained enzymatic activity, however instead of the allosteric behavior seen with wild type enzyme it displayed Michaelis-Menten kinetic behavior. With the substrate Abz-GGFLRKHGQ-EDDnp, monomeric IDE retained approximately 25% of the wild type activity. In contrast with the larger peptide substrates beta-endorphin and amyloid beta peptide 1-40, monomeric IDE retained only 1 to 0.25% of wild type activity. Unlike wild type IDE neither bradykinin nor dynorphin B-9 activated the monomeric variant of the enzyme. Similarly, monomeric IDE was not activated by polyphosphates under conditions in which the activity of wild type enzyme was increased more than 50 fold. CONCLUSIONS/SIGNIFICANCE: These findings serve to establish the dimer interface in IDE and demonstrate the requirement for an oligomeric form of the enzyme for its regulatory properties. The data support a mechanism where the binding of activators to oligomeric IDE induces a conformational change that cannot occur in the monomeric variant. Since a conformational change from a closed to a more open structure is likely the rate-determining step in the IDE reaction, the subunit induced conformational change likely shifts the structure of the oligomeric enzyme to a more open conformation.

  5. Honatisine, a novel diterpenoid alkaloid, and six known alkaloids from Delphinium honanense and their cytotoxic activity.

    Science.gov (United States)

    He, Yang Qing; Ma, Zhan Ying; Wei, Xiao Mei; Liu, Dong Jie; Du, Bao Zhong; Yao, Bing Hua; Gao, Li Ming

    2011-11-01

    A novel diterpene alkaloid named honatisine (1) has been isolated from the whole plants of Delphinium honanense, along with six known alkaloids, siwanine E (2), isoatisine (3), atisine (4), delcorinine (5), uraphine (6), and nordhagenine A (7). Their structures were deduced on the basis of their spectral data. All of them were evaluated by a SRB assay for their cytotoxicity, and compound 1 showed a significant cytotoxic activity (IC(50) =3.16 μM) against the MCF-7 cell line.

  6. Alkaloid diversity in Galanthus elwesii and Galanthus nivalis.

    Science.gov (United States)

    Berkov, Strahil; Bastida, Jaume; Sidjimova, Borjana; Viladomat, Francesc; Codina, Carles

    2011-01-01

    Seventy alkaloids of galanthamine, lycorine, homolycorine, tazettine, haemanthamine, narciclasine, and tyramine types were detected by GC/MS in 25 Galanthus elwesii and seven Galanthus nivalis populations, collected from different locations in Bulgaria. Intraspecies diversity in the alkaloid profiles regarding the main alkaloid types (chemotypes) was observed. Tyramine-type protoalkaloids (namely, hordenine and its derivatives) were dominant in 19 populations of G. elwesii. In other populations of G. elwesii, the plants accumulated mainly homolycorine-, lycorine-, and galanthamine-type alkaloids. The alkaloid profiles of G. nivalis were dominated by narciclasine-, galanthamine-, lycorine-, haemanthamine-, or tazettine-type compounds. Geographical distribution of chemotypes indicated a relationship between populations, since adjacent populations often displayed similar alkaloid profiles. The results from year-to-year sampling and transplantation experiments imply genetic determination of alkaloid synthesis in the two studied species of Galanthus.

  7. Therapeutic Potential of Steroidal Alkaloids in Cancer and Other Diseases.

    Science.gov (United States)

    Jiang, Qi-Wei; Chen, Mei-Wan; Cheng, Ke-Jun; Yu, Pei-Zhong; Wei, Xing; Shi, Zhi

    2016-01-01

    Steroidal alkaloids are a class of secondary metabolites isolated from plants, amphibians, and marine invertebrates. Evidence accumulated in the recent two decades demonstrates that steroidal alkaloids have a wide range of bioactivities including anticancer, antimicrobial, anti-inflammatory, antinociceptive, etc., suggesting their great potential for application. It is therefore necessary to comprehensively summarize the bioactivities, especially anticancer activities and mechanisms of steroidal alkaloids. Here we systematically highlight the anticancer profiles both in vitro and in vivo of steroidal alkaloids such as dendrogenin, solanidine, solasodine, tomatidine, cyclopamine, and their derivatives. Furthermore, other bioactivities of steroidal alkaloids are also discussed. The integrated molecular mechanisms in this review can increase our understanding on the utilization of steroidal alkaloids and contribute to the development of new drug candidates. Although the therapeutic potentials of steroidal alkaloids look promising in the preclinical and clinical studies, further pharmacokinetic and clinical studies are mandated to define their efficacy and safety in cancer and other diseases.

  8. Alkaloid production by callous tissue cultures of Cereus peruvianus (Cactaceae).

    Science.gov (United States)

    de Oliveira, Arildo José Braz; Machado, Maria Fátima Pires da Silva

    2003-02-01

    The morphologically undifferentiated cells of nonregenerant callous tissue of Cereus peruvianus cultured in the original medium and in medium supplemented with tyrosine were used as an alkaloid source. Comparison of alkaloid production by C. peruvianus plants and by callous tissues indicated that alkaloid levels were almost twice as high in callous tissues as in shoots of C. peruvianus plants. The ratio of alkaloid concentration between mature plant and morphologically undifferentiated cells of callous tissue was 1:1.7. A relationship between culture medium containing tyrosine and alkaloid production was also observed in the callous tissues of C. peruvianus. Since increased alkaloid production may be induced by additional factors such as tyrosine, increasing levels of tyrosine or other conditions of the culture medium may be considered factors for inducing higher alkaloid production by C. peruvianus callous tissues.

  9. The Alkaloid Profiles of Lupinus sulphureus

    Science.gov (United States)

    Lupines are common plants found on the rangelands in the western United States. Lupines are known to contain alkaloids that can be toxic and teratogenic causing congenital birth defects (crooked calf disease). One such lupine, Lupinus sulphureus, occurs in parts of Oregon, Washington, and British ...

  10. Two New Oxoaporphine Alkaloids from Thalictrum elegans

    Institute of Scientific and Technical Information of China (English)

    梁志远; 杨小生; 汪冶; 郝小江

    2005-01-01

    Two new oxoaporphine alkaloids, 1,2,3,10-tetramethoxy-9-(2-hydroxy-4,5-dimethoxybenzyloxy)oxoaporphine (1) and 1,2,3,10-tetramethoxy-9-(4,5-dimethoxy-2-formylphenoxy)oxoaporphine (2), were isolated from Thalictrum elegans. Their structures were elucidated based on spectroscopic analysis including 1D, 2D NMR, IR and MS.

  11. Alkaloids from Oriciopsis glaberrima Engl. (Rutaceae).

    Science.gov (United States)

    Wansi, Jean Duplex; Wandji, Jean; Kamdem Waffo, Alain François; Ngeufa, Happi Emmanuel; Ndom, Jean Claude; Fotso, Serge; Maskey, Rajendra Prasad; Njamen, Dieudonné; Fomum, Tanee Zacharias; Laatsch, Harmut

    2006-03-01

    Two alkaloid derivatives, oriciacridone A and B, were isolated from the stem bark of Oriciopsis glaberrima (Rutaceae). The structures were elucidated by a detailed spectroscopic analysis. The extract exhibited in vitro significant antimicrobial activity against a range of micro-organisms.

  12. Ergot alkaloids decrease rumen epithelial blood flow

    Science.gov (United States)

    Two experiments were conducted to determine if ergot alkaloids affect blood flow to the absorptive surface of the rumen of steers. Steers (n=8 total) were pair-fed alfalfa cubes at 1.5× NEM and received ground endophyte-infected tall fescue seed (E+) or endophyte-free tall fescue seed (E-) via rumen...

  13. Eremophilanes and Pyrrolizidine Alkaloids of Senecioneae Species

    OpenAIRE

    2014-01-01

    The chemical study of two species of the tribe Senecioneae afforded two eremophilanes and two pyrrolizidine alkaloids from Se - necio subauriculatus and four modified eremophilanes from Roldana oaxacana . The chemistry of these species is in accord with that re - ported for species of Senecio and Roldana studied so far, and therefore, with the already described for the tribe Senecioneae.

  14. Histrionicotoxin alkaloids finally detected in an ant

    DEFF Research Database (Denmark)

    Jones, Tappey H.; Adams, Rachelle Martha Marie; Spande, Thomas F.

    2012-01-01

    Workers of the ant Carebarella bicolor collected in Panama were found to have two major poison-frog alkaloids, cis- and trans-fused decahydroquinolines (DHQs) of the 269AB type, four minor 269AB isomers, two minor 269B isomers, and three isomers of DHQ 271D. For the first time in an ant, however......, the DHQs were accompanied by six histrionicotoxins (HTXs), viz., 283A, 285A, 285B, 285C, 287A, and 287D. This co-occurrence of the HTX and DHQ alkaloids is the usual pattern seen in dendrobatid frogs. This finding contrasts with our earlier study, where workers of a Brazilian ant, Solenopsis (Diplorhoptrum......) sp., were found to have a very similar DHQ complex but failed to show HTXs. Several new DHQ alkaloids of MW 271 (named in the frog as 271G) are reported from the above ants that have both m/z 202 and 204 as major fragment ions, unlike the spectrum seen for the poison-frog alkaloid 271D, which has...

  15. A New Quinolizidine Alkaloid from Boehmeria siamensis

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new quinolizidine alkaloid, 3-(4-hydroxyphenyl)-4-(3-methoxy-4-hydroxyphenyl)-3, 4-dehydroquinolizidine (1), was isolated from the ethanol extract of the whole plants of Boehmeria siamensis Craib. Its structure was elucidated on the analysis of 1D NMR and 2D NMR spectrum.

  16. A New Alkaloid from Sinomenium acutum

    Institute of Scientific and Technical Information of China (English)

    Wei Ming CHENG; Feng QIU; Li Jun WU; Xin Sheng YAO

    2005-01-01

    Sinomenium acutum is widely used in East and South Asia for the treatment of many diseases, especially rheumatoid arthritis (RA). The chemical research on Sinomenium acutum led to the isolation of a new alkaloid compound (1). On the basis of chemical evidences and spectral analysis, 1 was identified as N-(1, 7-dimethoxylphenanthren-2-yl)acetamide.

  17. Dehydropyrrolizidine alkaloid toxicity, cytotoxicity, and carcinogenicity

    Science.gov (United States)

    Dehyro-pyrrolizidine alkaloid (PA)-containing plants compose about 5% of the world’s flowering plants and they commonly poison livestock, wildlife and humans. Previous work has produced considerable understanding of PA toxicity, species susceptibility, conditions and routes of exposure, toxin metab...

  18. A New Alkaloid from Isatis costata

    OpenAIRE

    Fatima, Itrat; Anis, Itrat; Ahmad, Ijaz; Malik, Abdul; Afza, Nighat

    2014-01-01

    A new alkaloid has been isolated from Isatis costata C.A.Mey. and assigned structure 1 on the basis of spectroscopic data including 1D and 2D NMR techniques. Methyl 2-acetoamidobenzoate (2), b-sitosterol (3), and ursolic acid (4) were also isolated for the first time from this species.

  19. A Novel Alkaloid from Stapelia hirsuta

    OpenAIRE

    SHABANA, Marwan; GONAID, Mariam; SALAMA, Maha Mahmoud; ABDEL-SATTAR, Essam

    2006-01-01

    A novel alkaloid (1,8,8-trimethyl-5,8-dihydro-1H-pyrano[3,4-b]pyridine-4,6-dione) was isolated from the chloroformic traction obtained from the total alcoholic extract of the aerial parts of Stapelia hirsuta L. In addition, apigenin, luteolin and b-sitosterol-3-O-b-D- glucopyranoside were also isolated.

  20. 27 CFR 21.99 - Brucine alkaloid.

    Science.gov (United States)

    2010-04-01

    ... dissolved by hydrochloric acid when several drops of a 1 N barium chloride solution are added to 10 ml of a... OF THE TREASURY LIQUORS FORMULAS FOR DENATURED ALCOHOL AND RUM Specifications for Denaturants § 21.99 Brucine alkaloid. (a) Identification test. Add a few drops of concentrated nitric acid to about 10 mg of...

  1. Alkaloids in the pharmaceutical industry: Structure, isolation and application

    Directory of Open Access Journals (Sweden)

    Nikolić Milan

    2003-01-01

    Full Text Available By the end of the 18th and the beginning of the 19th century a new era began in medicine, pharmaceutics and chemistry that was strongly connected with alkaloids and alkaloid drugs. Even before that it was known that certain drugs administered in limited doses were medicines, and toxic if taken in larger doses (opium, coke leaves, belladonna roots, monkshood tubers crocus or hemlock seeds. However, the identification, isolation and structural characterization of the active ingredients of the alkaloid drugs was only possible in the mid 20th century by the use of modern extraction equipment and instrumental methods (NMR, X-ray diffraction and others.In spite of continuing use over a long time, there is still great interest in investigating new drugs, potential raw materials for the pharmaceutical industry, as well as the more detailed investigation and definition of bio-active components and the indication of their activity range, and the partial synthesis of new alkaloid molecules based on natural alkaloids. The scope of these investigations, especially in the field of semi-synthesis is to make better use of the bio-active ingredients of alkaloid drugs, i.e. to improve the pharmacological effect (stronger and prolonged effect of the medicine, decreased toxicity and side effects, or to extend or change the applications. A combined classification of alkaloids was used, based on the chemical structure and origin, i.e. the source of their isolation to study alkaloid structure. For practical reasons, the following classification of alkaloids was used: ergot alkaloids, poppy alkaloids, tropanic alkaloids purine derivative alkaloids, carbon-cyclic alkaloids, and other alkaloids. The second part of this report presents a table of general procedures for alkaloid isolation from plant drugs (extraction by water non-miscible solvents, extraction by water-miscible solvents and extraction by diluted acid solutions. Also, methods for obtaining chelidonine and

  2. Anthocyanins and their variation in red wines I. Monomeric anthocyanins and their color expression.

    Science.gov (United States)

    He, Fei; Liang, Na-Na; Mu, Lin; Pan, Qiu-Hong; Wang, Jun; Reeves, Malcolm J; Duan, Chang-Qing

    2012-02-07

    Originating in the grapes, monomeric anthocyanins in young red wines contribute the majority of color and the supposed beneficial health effects related to their consumption, and as such they are recognized as one of the most important groups of phenolic metabolites in red wines. In recent years, our increasing knowledge of the chemical complexity of the monomeric anthocyanins, their stability, together with the phenomena such as self-association and copigmentation that can stabilize and enhance their color has helped to explain their color representation in red wine making and aging. A series of new enological practices were developed to improve the anthocyanin extraction, as well as their color expression and maintenance. This paper summarizes the most recent advances in the studies of the monomeric anthocyanins in red wines, emphasizing their origin, occurrence, color enhancing effects, their degradation and the effect of various enological practices on them.

  3. Anthocyanins and Their Variation in Red Wines I. Monomeric Anthocyanins and Their Color Expression

    Directory of Open Access Journals (Sweden)

    Chang-Qing Duan

    2012-02-01

    Full Text Available Originating in the grapes, monomeric anthocyanins in young red wines contribute the majority of color and the supposed beneficial health effects related to their consumption, and as such they are recognized as one of the most important groups of phenolic metabolites in red wines. In recent years, our increasing knowledge of the chemical complexity of the monomeric anthocyanins, their stability, together with the phenomena such as self-association and copigmentation that can stabilize and enhance their color has helped to explain their color representation in red wine making and aging. A series of new enological practices were developed to improve the anthocyanin extraction, as well as their color expression and maintenance. This paper summarizes the most recent advances in the studies of the monomeric anthocyanins in red wines, emphasizing their origin, occurrence, color enhancing effects, their degradation and the effect of various enological practices on them.

  4. B22 Glu Des-B30 Insulin: A Novel Monomeric Insulin

    Institute of Scientific and Technical Information of China (English)

    Hai-Juan DU; Jia-Hao SHI; Da-Fu CUI; You-Shang ZHANG

    2006-01-01

    Studies on monomeric insulin with reduced self-association are important in the development of insulin pharmaceutical preparations with rapid hypoglycemic action on patients with diabetes. Here we report a novel monomeric insulin, B22 Glu des-B30 insulin, prepared from a single chain insulin precursor with B22 Arg mutated to Glu, which was expressed in Pichia pastoris and converted to B22 Glu des-B30 insulin by tryptic digestion. It still retains 50% of the in vivo biological activity of porcine insulin and does not form a dimer even at a concentration of 10 mg/ml, showing that B22 Glu plays a key role in reducing the selfassociation of the insulin molecule without greatly reducing its biological activity. This novel monomeric insulin might have potential applications in the clinic.

  5. Insecticidal Constituents and Activity of Alkaloids from Cynanchum mongolicum.

    Science.gov (United States)

    Ge, Yang; Liu, Pingping; Yang, Rui; Zhang, Liu; Chen, Hongxing; Camara, Ibrahima; Liu, Yiqing; Shi, Wangpeng

    2015-09-21

    Based on MS and NMR data and bioassay-guided tracing, three insecticidal alkaloids I, II and III from Cynanchum mongolicum were identified to be antofine N-oxide, antofine and tylophorine. Alkaloid I was more toxic than alkaloids II and III, but they were less active against Spodoptera litura than total alkaloids. The contact toxicity from these alkaloids against the aphid Lipaphis erysimi was significant, as the 24 h-LC50 values of alkaloids I, II, III and total alkaloids were 292.48, 367.21, 487.791 and 163.52 mg/L, respectively. The development disruption of S. litura larvae was tested, the pupation and emergence rates of S. litura decreased and the acute mortality of S. litura increased significantly by day 3 after being injected in their body cavity with 10-40 mg/L of total alkaloid. The ecdysone titer of treated S. litura larvae and prepupae declined with increasing alkaloid concentration. The alkaloids of Cynanchum mongolicum are potential insect growth inhibitors.

  6. Overexpression of ORCA3 and G10H in Catharanthus roseus plants regulated alkaloid biosynthesis and metabolism revealed by NMR-metabolomics.

    Directory of Open Access Journals (Sweden)

    Qifang Pan

    Full Text Available In order to improve the production of the anticancer dimeric indole alkaloids in Catharanthuse roseus, much research has been dedicated to culturing cell lines, hairy roots, and efforts to elucidate the regulation of the monoterpenoid indole alkaloid (MIA biosynthesis. In this study, the ORCA3 (Octadecanoid-derivative Responsive Catharanthus AP2-domain gene alone or integrated with the G10H (geraniol 10-hydroxylase gene were first introduced into C. roseus plants. Transgenic C. roseus plants overexpressing ORCA3 alone (OR lines, or co-overexpressing G10H and ORCA3 (GO lines were obtained by genetic modification. ORCA3 overexpression induced an increase of AS, TDC, STR and D4H transcripts but did not affect CRMYC2 and G10H transcription. G10H transcripts showed a significant increase under G10H and ORCA3 co-overexpression. ORCA3 and G10H overexpression significantly increased the accumulation of strictosidine, vindoline, catharanthine and ajmalicine but had limited effects on anhydrovinblastine and vinblastine levels. NMR-based metabolomics confirmed the higher accumulation of monomeric indole alkaloids in OR and GO lines. Multivariate data analysis of (1H NMR spectra showed change of amino acid, organic acid, sugar and phenylpropanoid levels in both OR and GO lines compared to the controls. The result indicated that enhancement of MIA biosynthesis by ORCA3 and G10H overexpression might affect other metabolic pathways in the plant metabolism of C. roseus.

  7. Alkaloids Isolated from Natural Herbs as the Anticancer Agents

    Directory of Open Access Journals (Sweden)

    Jin-Jian Lu

    2012-01-01

    Full Text Available Alkaloids are important chemical compounds that serve as a rich reservoir for drug discovery. Several alkaloids isolated from natural herbs exhibit antiproliferation and antimetastasis effects on various types of cancers both in vitro and in vivo. Alkaloids, such as camptothecin and vinblastine, have already been successfully developed into anticancer drugs. This paper focuses on the naturally derived alkaloids with prospective anticancer properties, such as berberine, evodiamine, matrine, piperine, sanguinarine, and tetrandrine, and summarizes the mechanisms of action of these compounds. Based on the information in the literature that is summarized in this paper, the use of alkaloids as anticancer agents is very promising, but more research and clinical trials are necessary before final recommendations on specific alkaloids can be made.

  8. Chlorinated alkaloids in Menispermum dauricum DC: root culture.

    Science.gov (United States)

    Sugimoto, Y; Babiker, H A; Saisho, T; Furumoto, T; Inanaga, S; Kato, M

    2001-05-18

    Feeding experiments using (36)Cl showed that Menispermum dauricum root culture produces four alkaloids containing chlorine. They included the novel alkaloids dauricumine and dauricumidine as well as the known alkaloids acutumine and acutumidine. The structures of novel alkaloids were established by spectroscopic, crystallographic, and chemical methods. These four alkaloids were labeled with (36)Cl, isolated, and fed independently to root cultures. Mutual conversion between acutumine and acutumidine, and between dauricumine and dauricumidine by N-methylation and N-demethylation, was demonstrated. Moreover, dauricumine was converted to acutumine and acutumidine. Epimerization of acutumidine to dauricumidine or vice versa was not observed. These results suggest that dauricumine is the first chlorinated alkaloid formed in cultured M. dauricum roots. Skewed distribution of radioactivity derived from labeled dauricumine is proof that epimerization at C-1 proceeds at a lower rate than N-demethylation.

  9. Recent developments in the chemistry of quinazolinone alkaloids.

    Science.gov (United States)

    Kshirsagar, U A

    2015-09-28

    Quinazolinones, an important class of fused heterocyclic alkaloids has attracted high attention in organic and medicinal chemistry due to their significant and wide range of biological activities. There are approximately 150 naturally occurring quinazolinone alkaloids known till 2005. Several new quinazolinone alkaloids (∼55) have been isolated in the last decade. Natural quinazolinones with exotic structural features and remarkable biological activities have incited a lot of activities in the synthetic community towards the development of new synthetic strategies and approaches for the total synthesis of quinazolinone alkaloids. This review is focused on these advances in the chemistry of quinazolinone alkaloids in the last decade. This article covers the newly isolated quinazolinone natural products with their biological activities and the recently reported total syntheses of quinazolinone alkaloids from 2006 to 2015.

  10. Toxicosis by Plant Alkaloids in Humans and Animals in Colombia

    Directory of Open Access Journals (Sweden)

    Gonzalo J. Diaz

    2015-12-01

    Full Text Available Due to its tropical location, chains of mountains, inter-Andean valleys, Amazon basin area, eastern plains and shores on both the Atlantic and Pacific Oceans, Colombia has many ecosystems and the second largest plant biodiversity in the world. Many plant species, both native and naturalized, are currently recognized as toxic for both animals and humans, and some of them are known to cause their toxic effects due to their alkaloid content. Among these, there are plants containing the hepatotoxic pyrrolizidine alkaloids, neurotoxins such as the indolizidine alkaloid swainsonine and the piperidine alkaloids coniine and γ-coniceine and tropane alkaloids. Unfortunately, the research in toxic plants in Colombia is not nearly proportional to its plant biodiversity and the scientific information available is only very scarce. The present review aims at summarizing the scarce information about plant alkaloid toxicosis in animals and humans in Colombia.

  11. Toxicosis by Plant Alkaloids in Humans and Animals in Colombia

    Science.gov (United States)

    Diaz, Gonzalo J.

    2015-01-01

    Due to its tropical location, chains of mountains, inter-Andean valleys, Amazon basin area, eastern plains and shores on both the Atlantic and Pacific Oceans, Colombia has many ecosystems and the second largest plant biodiversity in the world. Many plant species, both native and naturalized, are currently recognized as toxic for both animals and humans, and some of them are known to cause their toxic effects due to their alkaloid content. Among these, there are plants containing the hepatotoxic pyrrolizidine alkaloids, neurotoxins such as the indolizidine alkaloid swainsonine and the piperidine alkaloids coniine and γ-coniceine and tropane alkaloids. Unfortunately, the research in toxic plants in Colombia is not nearly proportional to its plant biodiversity and the scientific information available is only very scarce. The present review aims at summarizing the scarce information about plant alkaloid toxicosis in animals and humans in Colombia. PMID:26690479

  12. Toxicosis by Plant Alkaloids in Humans and Animals in Colombia.

    Science.gov (United States)

    Diaz, Gonzalo J

    2015-12-11

    Due to its tropical location, chains of mountains, inter-Andean valleys, Amazon basin area, eastern plains and shores on both the Atlantic and Pacific Oceans, Colombia has many ecosystems and the second largest plant biodiversity in the world. Many plant species, both native and naturalized, are currently recognized as toxic for both animals and humans, and some of them are known to cause their toxic effects due to their alkaloid content. Among these, there are plants containing the hepatotoxic pyrrolizidine alkaloids, neurotoxins such as the indolizidine alkaloid swainsonine and the piperidine alkaloids coniine and γ-coniceine and tropane alkaloids. Unfortunately, the research in toxic plants in Colombia is not nearly proportional to its plant biodiversity and the scientific information available is only very scarce. The present review aims at summarizing the scarce information about plant alkaloid toxicosis in animals and humans in Colombia.

  13. Synthesis of the Marine Pyrroloiminoquinone Alkaloids, Discorhabdins

    Directory of Open Access Journals (Sweden)

    Yasufumi Wada

    2010-04-01

    Full Text Available Manynatural products with biologically interesting structures have been isolated from marine animals and plants such as sponges, corals, worms, etc. Some of them are discorhabdin alkaloids. The discorhabdin alkaloids (discorhabdin A-X, isolated from marine sponges, have a unique structure with azacarbocyclic spirocyclohexanone and pyrroloiminoquinone units. Due to their prominent potent antitumor activity, discorhabdins have attracted considerable attention. Many studies have been reported toward the synthesis of discorhabdins. We have accomplished the first total synthesis of discorhabdin A (1, having the strongest activity in vitro among discorhabdins in 2003. In 2009, we have also accomplished the first total synthesis of prianosin B (2, having the 16,17-dehydropyrroloiminoquinone moiety, by a novel dehydrogenation reaction with a catalytic amount of NaN3. These synthetic studies, as well as syntheses of the discorhabdins by various chemists to-date, are reviewed here.

  14. Total synthesis of the Daphniphyllum alkaloid daphenylline

    Science.gov (United States)

    Lu, Zhaoyong; Li, Yong; Deng, Jun; Li, Ang

    2013-08-01

    The Daphniphyllum alkaloids are a large class of natural products isolated from a genus of evergreen plants widely used in Chinese herbal medicine. They display a remarkable range of biological activities, including anticancer, antioxidant, and vasorelaxation properties as well as elevation of nerve growth factor. Daphenylline is a structurally unique member among the predominately aliphatic Daphniphyllum alkaloids, and contains a tetrasubstituted arene moiety mounted on a sterically compact hexacyclic scaffold. Herein, we describe the first total synthesis of daphenylline. A gold-catalysed 6-exo-dig cyclization reaction and a subsequent intramolecular Michael addition reaction, inspired by Dixon's seminal work, were exploited to construct the bridged 6,6,5-tricyclic motif of the natural product at an early stage, and the aromatic moiety was forged through a photoinduced olefin isomerization/6π-electrocyclization cascade followed by an oxidative aromatization process.

  15. Evaluation of Aconitum diterpenoid alkaloids as antiproliferative agents

    OpenAIRE

    Wada, Koji; Ohkoshi, Emika; Zhao, Yu; Goto, Masuo; Morris-Natschke, Susan L.; Lee, Kuo-Hsiung

    2015-01-01

    Little information has been reported on the antitumor effects of the diterpenoid alkaloid constituents of Aconitum plants, used in the herbal drug “bushi”. This study was aimed at determining the antitumor activities of Aconitum C19-and C20-diterpenoid alkaloids and synthetic derivatives against lung (A549), prostate (DU145), nasopharyngeal (KB), and vincristine-resistant nasopharyngeal (KB-VIN) cancer cell lines. Newly synthesized C20-diterpenoid alkaloid derivatives showed substantial suppr...

  16. A new monoterpenoid oxindole alkaloid from Hamelia patens micropropagated plantlets.

    Science.gov (United States)

    Paniagua-Vega, David; Cerda-García-Rojas, Carlos M; Ponce-Noyola, Teresa; Ramos-Valdivia, Ana C

    2012-11-01

    Chemical studies on Hamelia patens (Rubiaceae) micropropagated plantlets allowed production of a new monoterpenoid oxindole alkaloid, named (-)-hameline (7), together with eight known alkaloids, tetrahydroalstonine (1), aricine (2), pteropodine (3), isopteropodine (4), uncarine F (5), speciophylline (6), palmirine (8), and rumberine (9). The structure of the new alkaloid was assigned on the basis of 1D and 2D NMR spectroscopy, mass spectrometry, and molecular modeling.

  17. Initial Studies on Alkaloids from Lombok Medicinal Plants

    Directory of Open Access Journals (Sweden)

    John B. Bremner

    2001-01-01

    Full Text Available Initial investigation of medicinal plants from Lombok has resulted in the collection of 100 plant species predicted to have antimicrobial, including antimalarial, properties according to local medicinal uses. These plants represent 49 families and 80 genera; 23% of the plants tested positively for alkaloids. Among the plants testing positive, five have been selected for further investigation involving structure elucidation and antimicrobial testing on the extracted alkaloids. Initial work on structural elucidation of some of the alkaloids is reported briefly.

  18. Neurotoxic Alkaloids: Saxitoxin and Its Analogs

    OpenAIRE

    Mihali, Troco K; Moffitt, Michelle C.; Neilan, Brett A.; Maria Wiese; D’Agostino, Paul M.

    2010-01-01

    Saxitoxin (STX) and its 57 analogs are a broad group of natural neurotoxic alkaloids, commonly known as the paralytic shellfish toxins (PSTs). PSTs are the causative agents of paralytic shellfish poisoning (PSP) and are mostly associated with marine dinoflagellates (eukaryotes) and freshwater cyanobacteria (prokaryotes), which form extensive blooms around the world. PST producing dinoflagellates belong to the genera Alexandrium, Gymnodinium and Pyrodinium whilst production has been identified...

  19. Pyrrolizidine alkaloids and diterpenes from Villasenoria orcuttii

    Energy Technology Data Exchange (ETDEWEB)

    Arciniegas, Amira; Perez-Castorena, Ana L.; Gonzalez, Karina; Vivar, Alfonso Romo de, E-mail: alperezc@unam.mx [Instituto de Quimica, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, Coyoacan, DF (Mexico); Reyes-Lezama, Marisol [Centro Conjunto de Investigacion en Quimica Sustentable, Universidad Autonoma del Estado de Mexico-Universidad Nacional Autonoma de Mexico (UAEM-UNAM), Carretera Toluca-Atlacomulco, Estado de Mexico (Mexico); Villasenor, Jose Luis [Instituto de Biologia, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Ciudad Universitaria, Coyoacan, DF, (Mexico)

    2013-07-15

    The chemical study of Villasenoria orcuttii, the only species of the genus Villasenoria, afforded three acyclic diterpenes, two of them described for the first time. Two pyrrolizidine alkaloids, florosenine and floridanine, among other known compounds were also isolated. The absolute configuration of floridanine was determined by X-ray analysis using anomalous dispersion with Cu K{sub {alpha}} radiation, and its {sup 1}H and {sup 13}C nuclear magnetic resonance (NMR) data were corrected. (author)

  20. Pyrrolizidine Alkaloids from Onosmakaheirei Teppner (Boraginaceae

    Directory of Open Access Journals (Sweden)

    Ioanna Maria Orfanou

    2016-03-01

    Full Text Available The new pyrrolizidine alkaloid (PA 3΄-O-acetylechinatine N-oxide (7, along with two more known PAs (5, 6, two known flavonoids (3, 4, one known alkannin (1, two known triterpenoids, one known sterol, and allantoin (2 were isolated from the aerial parts of Onosma kaheirei. In addition, the retention indeces of the reduced PAs 6 and 7 were determined in a DB-5 WCOT column, to aid their detection by GC/MS in the future.

  1. New indole alkaloids from Sarcocephalus latifolius.

    Science.gov (United States)

    Abreu, P; Pereira, A

    2001-01-01

    Phytochemical investigation of the root extract of Sarcocephalus latifolius has led to the isolation of the new indole alkaloids 21-O-methylstrictosamide aglycone and 21-O-ethylstrictosamide aglycone, together with strictosamide, angustine, nauclefine, angustidine, angustoline, 19-O-ethylangustoline, naucleidinal, 19-epi-naucleidinal, quinovic acid-3 beta-O-beta-D-fucopyranoside, quinovic acid-3 beta-O-alpha-L-rhamnopyranoside, scopoletin, and beta-sitosterol. Strictosamide displayed moderate antiplasmodial activity against Plasmodium falciparum.

  2. A novel method to highly versatile monomeric PNA building blocks by multi component reactions

    NARCIS (Netherlands)

    Dömling, Alexander; Chi, Kai-Zu; Barrère, Mathieux

    1999-01-01

    A novel approach to monomeric PNA building blocks by a solution phase Ugi multi component reaction (MCR) is described. The reaction is easily performed in 96 well plates. The products precipitate from the reaction solution and are thus obtained in high yields and purity. Those products are not amena

  3. Monomeric G-proteins as signal transducers in airway physiology and pathophysiology

    NARCIS (Netherlands)

    Schaafsma, Dedmer; Roscioni, Sara S.; Meurs, Herman; Schmidt, Martina

    2008-01-01

    Monomeric G-proteins, also referred to as small GTPases, function as biological hubs being activated by extracellular stimuli and regulate downstream signalling events, which result in different cellular responses. The importance of these mechanisms is mirrored by the fact that several pathological

  4. Self-healing mechanism based on dispersed solid particles of various monomeric bismaleimides

    NARCIS (Netherlands)

    Turkenburg, D.H.; Fischer, H.R.

    2016-01-01

    In view of self-healing materials for high temperature applications we have studied the use of solid monomeric bismaleimide particles as embedded self-healing component dispersed in a host material. Below the self-healing activation temperature, bismaleimides remain inert while above it they may rap

  5. Monomeric red fluorescent protein variants used for imaging studies in different species

    NARCIS (Netherlands)

    Mueller-Taubenberger, Annette; Vos, Michel J.; Boettger, Angelika; Lasi, Margherita; Lai, Frank P. L.; Fischer, Markus; Rottner, Klemens

    2006-01-01

    Fluorescent proteins have proven to be excellent tools for live-cell imaging studies. In addition to green fluorescent protein (GFP) and its variants, recent progress was achieved in the development of monomeric red fluorescent proteins (mRFPs) that show improved properties in respect to maturation

  6. Monomeric and dendritic second generation Grubbs- and Hoveyda-Grubbs-type catalysts for olefin metathesis Metallodendrimers Special Issue

    NARCIS (Netherlands)

    Pijnenburg, Niels J M; Tomás-Mendivil, Eder; Mayland, Kimberley E.; Kleijn, Henk; Lutz, Martin; Spek, Anthony L.; Van Koten, Gerard; Klein Gebbink, Bert

    2014-01-01

    The synthesis and characterization of monomeric and dendritic Grubbs II and Hoveyda-Grubbs II-based complexes are reported. These complexes were synthesized via a route based on the connection of monomeric or dendritic N-alkyl-N′-mesitylimidazol-2-ylidene pre-ligands to Grubbs I or Hoveyda-Grubbs I

  7. Ergot Alkaloids (Regenerate New Leads as Antiparasitics.

    Directory of Open Access Journals (Sweden)

    John D Chan

    Full Text Available Praziquantel (PZQ is a key therapy for treatment of parasitic flatworm infections of humans and livestock, but the mechanism of action of this drug is unresolved. Resolving PZQ-engaged targets and effectors is important for identifying new druggable pathways that may yield novel antiparasitic agents. Here we use functional, genetic and pharmacological approaches to reveal that serotonergic signals antagonize PZQ action in vivo. Exogenous 5-hydroxytryptamine (5-HT rescued PZQ-evoked polarity and mobility defects in free-living planarian flatworms. In contrast, knockdown of a prevalently expressed planarian 5-HT receptor potentiated or phenocopied PZQ action in different functional assays. Subsequent screening of serotonergic ligands revealed that several ergot alkaloids possessed broad efficacy at modulating regenerative outcomes and the mobility of both free living and parasitic flatworms. Ergot alkaloids that phenocopied PZQ in regenerative assays to cause bipolar regeneration exhibited structural modifications consistent with serotonergic blockade. These data suggest that serotonergic activation blocks PZQ action in vivo, while serotonergic antagonists phenocopy PZQ action. Importantly these studies identify the ergot alkaloid scaffold as a promising structural framework for designing potent agents targeting parasitic bioaminergic G protein coupled receptors.

  8. A new diketopiperazine alkaloid from Aspergillus oryzae.

    Science.gov (United States)

    Shaaban, Mohamed; El-Metwally, Mohammad Magdy; Nasr, Hamdi

    2014-01-01

    Investigation of bioactive secondary metabolites from terrestrial Aspergillus oryzae sp. MMAO1 using M2 medium afforded a new diketopiperazine alkaloid, 7,9-dihydroxy-3-(1H-indol-3-ylmethyl)-8-methoxy-2,3,11,11a-tetrahydro-6H-pyrazino[1,2-b]isoquinoline-1,4-dione (1a), containing the unusual amino acid L-6,8-dihydroxy-7-methoxyphenylalanine. This was co-isolated with ditryptophenaline (2), cyclo-(Tryp,Tyr) (4), cyclo-(Pro,Val), α-cyclopiazonic acid (3), kojic acid and uridine. Re-cultivation of the fungal strain on Dox medium led to the production of bisdethio(bismethylthio)gliotoxin (5), pseurotin A (6) along with linoleic acid, α-cyclopiazonic acid (3) and kojic acid. The chemical structure of the new diketopiperazine alkaloid including the relative configuration was determined by 1D and 2D NMR spectroscopy and HR-ESI-MS spectrometry, and by comparison with the related literature. The new alkaloid (1a) showed no antimicrobial activity or cytotoxicity against brine shrimps.

  9. Drug development against tuberculosis: Impact of alkaloids.

    Science.gov (United States)

    Mishra, Shardendu K; Tripathi, Garima; Kishore, Navneet; Singh, Rakesh K; Singh, Archana; Tiwari, Vinod K

    2017-09-08

    Despite of the advances made in the treatment and management, tuberculosis (TB) still remains one of main public health problem. The contrary effects of first and second-line anti-tuberculosis drugs have generated extended research interest in natural products in the hope of devising new antitubercular leads. Interestingly, plethoras of natural products have been discovered to exhibit activity towards various resistant strains of M. tuberculosis. Extensive applications of alkaloids in the field of therapeutics is well-established and nowday's researches being pursued to develop new potent drugs from natural sources for tuberculosis. Alkaloids are categorized in quite a few groups according to their structures and isolation from both terrestrial and marine sources. These new drugs might be a watershed in the battle against tuberculosis. This review summarizes alkaloids, which were found active against Mycobacteria since last ten years with special attention on the study of structure-activity relationship (SAR) and mode of action with their impact in drug discovery and development against tuberculosis. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  10. Plant alkaloids as drug leads for Alzheimer's disease.

    Science.gov (United States)

    Ng, Yu Pong; Or, Terry Cho Tsun; Ip, Nancy Y

    2015-10-01

    Alzheimer's disease (AD) is a neurodegenerative illness associated with dementia and is most prevalent among the elderly population. Current medications can only treat symptoms. Alkaloids are structurally diverse and have been an important source of therapeutics for various brain disorders. Two US Food and Drug Administration (FDA)-approved acetylcholinesterase inhibitors for AD, galantamine and rivastigmine, are in fact alkaloids. In addition, clinical trials of four other extensively studied alkaloids-huperzine A, caffeine, nicotine, and indomethacin-have been conducted but do not convincingly demonstrate their clinical efficacy for AD. Interestingly, rhynchophylline, a known neuroprotective alkaloid, was recently discovered by in silico screening as an inhibitor of EphA4, a novel target for AD. Here, we review the pathophysiological mechanisms underlying AD, current treatment strategies, and therapeutic potential of several selected plant alkaloids in AD, highlighting their various drug targets and the key supportive preclinical and clinical studies. Future research should include more rigorous clinical studies of the most promising alkaloids, the further development of recently discovered candidate alkaloids, and the continual search for new alkaloids for relevant drug targets. It remains promising that an alkaloid drug candidate could significantly affect the progression of AD in addition to providing symptomatic relief.

  11. New Perspectives in the Chemistry of Marine Pyridoacridine Alkaloids.

    Science.gov (United States)

    Plodek, Alois; Bracher, Franz

    2016-01-26

    Secondary metabolites from marine organisms are a rich source of novel leads for drug development. Among these natural products, polycyclic aromatic alkaloids of the pyridoacridine type have attracted the highest attention as lead compounds for the development of novel anti-cancer and anti-infective drugs. Numerous sophisticated total syntheses of pyridoacridine alkaloids have been worked out, and many of them have also been extended to the synthesis of libraries of analogues of the alkaloids. This review summarizes the progress in the chemistry of pyridoacridine alkaloids that was made in the last one-and-a-half decades.

  12. TOXIC PYRROLIZIDINE ALKALOIDS OF ECHIUM AMOENUM FISCH. & MEY.

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    MITRA MEHRABANI

    2006-06-01

    Full Text Available Toxic pyrrolizidine alkaloids are present in some species of Echium (Boraginaceae. In this study petals of Echium amoenum Fisch. & Mey. (Gol-e-Gavzaban as a popular herbal medicine in Iran, were investigated for pyrrolizidine alkaloids (PAs. The alkaloids were separated and purified by preparative TLC and characterized by IR, one and two dimensional 1H and 13C-NMR and Mass spectroscopy. Four toxic alkaloids namely: echimidine I, echimidine isomer II, 7-angeloyl retronecine III and 7-tigloyl retronecine IV were identified.

  13. Binding Parameters of Alkaloids Berberine and Sanguinarine with DNA

    CERN Document Server

    Gumenyuk, V G; Kutovyy, S Yu; Yashchuk, V M; Zaika, L A

    2012-01-01

    We study the interaction of berberine and sanguinarine (plant alkaloids) with DNA in aqueous solutions, by using optical spectroscopy methods (absorption and fluorescence). The dependencies of alkaloid spectral characteristics on the concentration ratio N/c between the DNA base pairs and alkaloid molecules in the solutions are considered, and the manifestations of the alkaloid-DNA binding are revealed. The character of binding is found to depend on N/c. The parameters of the binding of berberine and sanguinarine with DNA are determined, by using the modified Scatchard and McGhee-von Hippel equations

  14. Evaluation of Biosynthetic Pathway and Engineered Biosynthesis of Alkaloids

    Directory of Open Access Journals (Sweden)

    Shinji Kishimoto

    2016-08-01

    Full Text Available Varieties of alkaloids are known to be produced by various organisms, including bacteria, fungi and plants, as secondary metabolites that exhibit useful bioactivities. However, understanding of how those metabolites are biosynthesized still remains limited, because most of these compounds are isolated from plants and at a trace level of production. In this review, we focus on recent efforts in identifying the genes responsible for the biosynthesis of those nitrogen-containing natural products and elucidating the mechanisms involved in the biosynthetic processes. The alkaloids discussed in this review are ditryptophenaline (dimeric diketopiperazine alkaloid, saframycin (tetrahydroisoquinoline alkaloid, strictosidine (monoterpene indole alkaloid, ergotamine (ergot alkaloid and opiates (benzylisoquinoline and morphinan alkaloid. This review also discusses the engineered biosynthesis of these compounds, primarily through heterologous reconstitution of target biosynthetic pathways in suitable hosts, such as Escherichia coli, Saccharomyces cerevisiae and Aspergillus nidulans. Those heterologous biosynthetic systems can be used to confirm the functions of the isolated genes, economically scale up the production of the alkaloids for commercial distributions and engineer the biosynthetic pathways to produce valuable analogs of the alkaloids. In particular, extensive involvement of oxidation reactions catalyzed by oxidoreductases, such as cytochrome P450s, during the secondary metabolite biosynthesis is discussed in details.

  15. Monomeric yeast PCNA mutants are defective in interacting with and stimulating the ATPase activity of RFC.

    Science.gov (United States)

    Ionescu, Costin N; Shea, Kathleen A; Mehra, Rajendra; Prundeanu, Lucia; McAlear, Michael A

    2002-10-29

    Yeast PCNA is a homo-trimeric, ring-shaped DNA polymerase accessory protein that can encircle duplex DNA. The integrity of this multimeric sliding DNA clamp is maintained through the protein-protein interactions at the interfaces of adjacent subunits. To investigate the importance of trimer stability for PCNA function, we introduced single amino acid substitutions at residues (A112T, S135F) that map to opposite ends of the monomeric protein. Recombinant wild-type and mutant PCNAs were purified from E. coli, and they were tested for their properties in vitro. Unlike the stable wild-type PCNA trimers, the mutant PCNA proteins behaved as monomers when diluted to low nanomolar concentrations. In contrast to what has been reported for a monomeric form of the beta clamp in E. coli, the monomeric PCNAs were compromised in their ability to interact with their associated clamp loader, replication factor C (RFC). Similarly, monomeric PCNAs were not effective in stimulating the ATPase activity of RFC. The mutant PCNAs were able to form mixed trimers with wild-type subunits, although these mixed trimers were unstable when loaded onto DNA. They were able to function as weak DNA polymerase delta processivity factors in vitro, and when the monomeric PCNA-41 (A112T, S135F double mutant) allele was introduced as the sole source of PCNA in vivo, the cells were viable and healthy. These pol30-41 mutants were, however, sensitive to UV irradiation and to the DNA damaging agent methylmethane sulfonate, implying that DNA repair pathways have a distinct requirement for stable DNA clamps.

  16. Dietary alkaloid sequestration in a poison frog: an experimental test of alkaloid uptake in Melanophryniscus stelzneri (Bufonidae).

    Science.gov (United States)

    Hantak, Maggie M; Grant, Taran; Reinsch, Sherri; McGinnity, Dale; Loring, Marjorie; Toyooka, Naoki; Saporito, Ralph A

    2013-12-01

    Several lineages of brightly colored anurans independently evolved the ability to secrete alkaloid-containing defensive chemicals from granular glands in the skin. These species, collectively referred to as 'poison frogs,' form a polyphyletic assemblage that includes some species of Dendrobatidae, Mantellidae, Myobatrachidae, Bufonidae, and Eleutherodactylidae. The ability to sequester alkaloids from dietary arthropods has been demonstrated experimentally in most poison frog lineages but not in bufonid or eleutherodactylid poison frogs. As with other poison frogs, species of the genus Melanophryniscus (Bufonidae) consume large numbers of mites and ants, suggesting they might also sequester defensive alkaloids from dietary sources. To test this hypothesis, fruit flies dusted with alkaloid/nutritional supplement powder were fed to individual Melanophryniscus stelzneri in two experiments. In the first experiment, the alkaloids 5,8-disubstituted indolizidine 235B' and decahydroquinoline were administered to three individuals for 104 days. In the second experiment, the alkaloids 3,5-disubstituted indolizidine 239Q and decahydroquinoline were given to three frogs for 153 days. Control frogs were fed fruit flies dusted only with nutritional supplement. Gas chromatography/mass spectrometry analyses revealed that skin secretions of all experimental frogs contained alkaloids, whereas those of all control frogs lacked alkaloids. Uptake of decahydroquinoline was greater than uptake of 5,8-disubstituted indolizidine, and uptake of 3,5-disubstituted indolizidine was greater than uptake of decahydroquinoline, suggesting greater uptake efficiency of certain alkaloids. Frogs in the second experiment accumulated a greater amount of alkaloid, which corresponds to the longer duration and greater number of alkaloid-dusted fruit flies that were consumed. These findings provide the first experimental evidence that bufonid poison frogs sequester alkaloid-based defenses from dietary

  17. Monoterpene Indole Alkaloids from the Fruit of Tabernaemontana litoralis and Differential Alkaloid Composition in Various Fruit Components.

    Science.gov (United States)

    Qu, Yang; Simonescu, Razvan; De Luca, Vincenzo

    2016-12-23

    Two new monoterpene indole alkaloids, isoakuammiline (1) and 18-hydroxypseudovincadifformine (2), and five known alkaloids, coronaridine (3), heyneanine (4), 3,19-oxidocoronaridine (5), tabersonine, and strictosidine, were identified from the fruit of Tabernaemontana litoralis. The structures of the alkaloids were determined using NMR and MS data analyses. While 18-hydroxypseudovincadifformine (2) showed a new hydroxylation pattern, isoakuammiline (1) revealed a novel skeleton for monoterpene indole alkaloids. In spite of the isolation of stemmadenine from the fruit tissues in other Tabernaemontana species, this vital biosynthetic precursor of iboga, aspidosperma, and pseudoaspidosperma skeletons was not found in T. litoralis.

  18. Galanthindole: a new indole alkaloid from Galanthus plicatus ssp. byzantinus.

    Science.gov (United States)

    Unver, Nehir; Kaya, G Irem; Werner, Christa; Verpoorte, Robert; Gözler, Belkis

    2003-09-01

    A new indole alkaloid, galanthindole, was isolated from Galanthus plicatus ssp. byzantinus (Amaryllidaceae), a plant native to northwestern Turkey. Incorporating a non-fused indole ring, galanthindole may represent the prototype of a new subgroup of the Amaryllidaceae alkaloids. Two other bases, (+)-11-hydroxyvittatine and hordenine, are also reported from the same plant.

  19. Gindarudine, a novel morphine alkaloid from Stephania glabra

    Institute of Scientific and Technical Information of China (English)

    Deepak Kumar Semwal; Usha Rawat

    2009-01-01

    A novel morphine alkaloid, named gindarudine 1 has been isolated from ethanol extract of Stephania glabra tubers, together with four known alkaloids, palmatine, dehydrocorydalmine, stepharanine, and 8-(4'-methoxybenzyl)-xylopinine. Compound 1 was elucidated as 3,6-O,N-detrimethyl-10-hydroxy-1-methoxy-thebaine by means of spectroscopic data including 2D NMR studies.

  20. [A new alkaloid of Menispermum dauricum DC--dauriciline].

    Science.gov (United States)

    Pang, X P; Chen, Y W; Li, X J; Long, J G

    1991-01-01

    A new phenolic dauricine-type alkaloid, named "dauriciline", was isolated from the rhizome of Menispermum dauricum DC. It is a pale yellow powder. Based on spectrometric analysis (UV.FAB-MS and 1HNMR) and chemical reaction the structure of the new alkaloid was elucidated as RR,7,7'-demethyldauricine (VI).

  1. Binding of quinolizidine alkaloids to nicotinic and muscarinic acetylcholine receptors.

    Science.gov (United States)

    Schmeller, T; Sauerwein, M; Sporer, F; Wink, M; Müller, W E

    1994-09-01

    Fourteen quinolizidine alkaloids, isolated from Lupinus albus, L. mutabilis, and Anagyris foetida, were analyzed for their affinity for nicotinic and/or muscarinic acetylcholine receptors. Of the compounds tested, the alpha-pyridones, N-methylcytisine and cytisine, showed the highest affinities at the nicotinic receptor, while several quinolizidine alkaloid types were especially active at the muscarinic receptor.

  2. Antiproliferative and Structure Activity Relationships of Amaryllidaceae Alkaloids.

    Science.gov (United States)

    Cedrón, Juan C; Ravelo, Ángel G; León, Leticia G; Padrón, José M; Estévez-Braun, Ana

    2015-07-30

    The antiproliferative activity of a set of seven natural Amaryllidaceae alkaloids and 32 derivatives against four cancer cell lines (A2780, SW1573, T47-D and WiDr) was determined. The best antiproliferative activities were achieved with alkaloids derived from pancracine (2), haemanthamine (6) and haemantidine (7). For each skeleton, some structure-activity relationships were outlined.

  3. Studies of interaction between two alkaloids and double helix DNA

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yantao [Key Laboratory of Preparation and Applications of Environmentally Friendly Materials (Jilin Normal University), Ministry of Education China, Siping 136000 (China); College of Chemistry, Jilin Normal University, Siping 136000 (China); Peng, Tingting [College of Chemistry, Jilin Normal University, Siping 136000 (China); College of Chemistry, Baicheng Normal University, Baicheng, 130032 (China); Zhao, Lei [Siping Institute for Food and Drug Control, Siping 136000 (China); Jiang, Dayu [Key Laboratory of Preparation and Applications of Environmentally Friendly Materials (Jilin Normal University), Ministry of Education China, Siping 136000 (China); College of Chemistry, Jilin Normal University, Siping 136000 (China); Cui, Yuncheng, E-mail: 1979yanzi@163.com [Key Laboratory of Preparation and Applications of Environmentally Friendly Materials (Jilin Normal University), Ministry of Education China, Siping 136000 (China); College of Chemistry, Jilin Normal University, Siping 136000 (China)

    2014-12-15

    This article presents the study on the interaction of two alkaloids (matrine and evodiamine) and hs-DNA by absorption, fluorescence, circular dichroism (CD), DNA melting and viscosity experiments. The spectroscopic studies suggested that two alkaloids can bind to DNA through an intercalative mode. The viscosity measurement and thermal denaturation also indicated that two alkaloids can intercalate to DNA. The binding constants (K{sub A}) and the number of binding sites (n) were determined. At the same time, some significant thermodynamic parameters of the binding of the alkaloids to DNA were obtained. Competitive binding studies revealed that alkaloids had an effect on ethidium bromide (EB) bound DNA. In addition, it was also proved that the fluorescence quenching was influenced by ionic strength. - Highlights: • Interaction between two alkaloids and DNA is studied by spectral methods. • The binding constant and the binding sites between two alkaloids and DNA are obtained. • There are a classical intercalative mode between alkaloids and DNA. • The binding of matrine with DNA is weaker than that of evodiamine. • It is important for us to understand the alkaloids–DNA interactions at a molecular level.

  4. ALKALOIDS OF SOME EUROPEAN AND MACARONESIAN SEDOIDEAE AND SEMPERVIVOIDEAE (CRASSULACEAE)

    NARCIS (Netherlands)

    STEVENS, JF; THART, H; HENDRIKS, H; MALINGRE, TM

    1992-01-01

    Some 22 pyrrolidine and piperdine alkaloids were detected in the leafy parts of Sedum acre, S. aetnense, S. anglicum, S. brissemoreti, S. farinosum, S. fusiforme, S. lancerottense, S. melanantherum, and S. nudum. In addition to the alkaloids known from S. acre, 1-(2-pyrrolidyl)-propan-2-one and 2-mo

  5. Pyrrolizidine alkaloids from Bulgarian species of the genus Senecio

    Directory of Open Access Journals (Sweden)

    NADEZHDA KOSTOVA

    2006-12-01

    Full Text Available Nine Bulgarian species from the genus Senecio were studied phytochemically and/or by GC-MS analysis. Senecivernine-N-oxide was isolated and identified by spectral data for the first time. Different types of pyrrolizidine alkaloids were tested for cytotoxicity on murine lymphocytes. At a concentration of 100 µg/ml, the alkaloid retroisosenine showed immunosuppressive effect.

  6. [Advance on pharmacologic actions, toxicity and pharmacokinetics of pyrrolizidine alkaloids].

    Science.gov (United States)

    Gao, Jiangguo; Wang, Changhong; Li, Yan; Wang, Zhengtao

    2009-03-01

    Plants containing pyrrolizidine alkaloids were widely used in traditional medicine. Its hepatotoxicity is main toxicity as well known internationally. In order to providing some foundation for the future studies, the advancement on the pharmacologic actions, toxicity, and pharmacokinetics or toxicokinetics of pyrrolizidine alkaloids was reviewed.

  7. Two New Norditerpenoid Alkaloids from Aconitum spicatum Stapf

    Institute of Scientific and Technical Information of China (English)

    Li Ming GAO; Xiao Mei WEI; Li YANG

    2005-01-01

    Two new norditerpenoid alkaloids, spicatine A (1) and spicatine B (2) were isolated from the root of Aconitum spicatum. The new compounds were deduced on the basis of their spectral data (IR, HREIMS, EIMS, 1D, 2D-NMR). This is the first whole report on the isolation of diterpenoid alkaloids from the A. spicatum Stapf.

  8. Evolution of alkaloid biosynthesis in the genus Narcissus.

    Science.gov (United States)

    Berkov, Strahil; Martínez-Francés, Vanessa; Bastida, Jaume; Codina, Carles; Ríos, Segundo

    2014-03-01

    In an attempt to reveal the relationships between alkaloid biosynthesis and phylogeny, we investigated by GC-MS the alkaloid patterns of 22 species and 3 hybrids (from 45 locations) from seven main sections of the genus Narcissus (Amaryllidaceae). The results indicate that the first alkaloids to evolve in the genus Narcissus were of the lycorine- and homolycorine-type. The alkaloid pattern of the Nevadensis section supports its recent separation from the Pseudonarcissus section. The plants of Narcissus pallidulus (Ganymedes section) show a predominance of Sceletium-type compounds, which are quite rare in the Amaryllidaceae family. Two successful evolutionary strategies involving alkaloid biosynthesis and leading to an expansion in taxa and occupied area were determined. Firstly, a diversification of alkaloid patterns and a high alkaloid concentration in the organs of the large Narcissus species (in the Pseudonarcissus section) resulted in an improved chemical defence in diverse habitats. Secondly, both plant size and alkaloid biosynthesis were reduced (in the Bulbocodium and Apodanthi sections) relegated to dry pastures and rocky places.

  9. Leptopyrine, new alkaloid from Leptopyrum fumarioides L. (Ranunculaceae).

    Science.gov (United States)

    Doncheva, Tsvetelina; Solongo, Amgalan; Kostova, Nadezhda; Gerelt-Od, Yadamsuren; Selenge, Dangaa; Philipov, Stefan

    2015-01-01

    A new type of isoquinoline alkaloid leptopyrine was isolated from the aerial parts of Leptopyrum fumarioides L. (Ranunculaceae) of Mongolian origin. The known alkaloids protopine and thalifoline were isolated for the first time from this the species. All structures were established by physical and spectral analyses.

  10. Alkaloids and Coumarins from the Leaves of Amyris diatripa.

    Science.gov (United States)

    Laguna, A

    1984-02-01

    The alkaloids edulinine and (+/-) isoplatydesmine were isolated from the leaves of Amyris diatripa, being the first report of the presence of alkaloids in species of this genus. The presence of coumarins in the plant was also shown by isolation of psoralen, bergapten, marmesin, ulopterol and suberenol.

  11. Alkaloids from the root barks of Goniothalamus cheliensis

    Institute of Scientific and Technical Information of China (English)

    Miao Miao Jiang; Xue Zhang; Yi Dai; Hao Gao; Hong Wei Liu; Nai Li Wang; Wen Cai Ye; Xin Sheng Yao

    2008-01-01

    (3S)-2-Oxo-5,12-dimethoxy-3-hydroxy-3-methylbenz[f]indoline (1), a new benzoxindole alkaloid, along with two known alkaloids, was isolated from the root barks of Goniothalamus cheliensis Hu. The structure was elucidated by spectroscopic evidences, and the absolute configuration was determined by CD spectrum.

  12. A new indole alkaloid isolated from Tabernaemontana hystrix steud (Apocynaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Monnerat, Cecilia Silva; Souza, Jucimar Jorgeane de; Mathias, Leda; Braz-Filho, Raimundo; Vieira, Ivo Jose C. [Universidade Estadual do Norte Fluminense (UENF), Campos dos Goytacases, RJ (Brazil). Setor de Quimica de Produtos Naturais]. E-mail: curcino@uenf.br

    2005-11-15

    A new alkaloid, named hystrixnine (1), and five known indole alkaloids, ibogamine (2), olivacine (3), affinine (4), affinisine (5) and Nb-methylaffinisine (6), were isolated from the root bark of Tabernaemontana hystrix. The known triterpenes a-amyrin acetate, b-amyrin acetate and lupeol acetate were also identified. The structures of the compounds were elucidated based on spectopic studies. (author)

  13. An Acetylenic Alkaloid from the Calcareous Sponge Leucetta sp.

    Directory of Open Access Journals (Sweden)

    Nicole J. de Voogd

    2011-03-01

    Full Text Available A new acetylenic alkaloid was isolated from the sponge Leucetta sp. The structure was established by analyzing spectroscopic data. The alkaloid showed cytotoxicity IC50 2.5 mg/mL against NBT-T2 cells.

  14. [Alkaloids of Vinca rosea L. introduced to Western Georgia].

    Science.gov (United States)

    Vachnadze, N S; Kintsurashvili, L G; Suladze, T Sh; Bakuridze, A D; Vachnadze, V Iu

    2013-11-01

    Vinca roseae L. (Саtharanthus rosea (L.) G. Don) was introduced at Kobuleti experimental station of medical plants. The object of investigation was the plant material of Vinca roseae L. collected in May, 2005., September, 2006 and October, 2009. Total alkaloids were obtained in accordance with Atta- ur-Rachman method. The variability of the quantitative and qualitative composition of total alkaloids and vincaleikoblastin (VLB) fraction during vegetation was studied. It was established that the maximal content of total alkaloids and VLB fraction of Vinca roseae L. is accumulated in the phase of secondary flowering, hence the collecting of a plant material is recommended to be made during the aforesaid vegetation phase as for this period it is a rather high output of a raw material, alkaloid complex and VLB faction. Alkaloids vinkaleikoblastin, ajmalicine and new epimer tetrahydroalstonine with С3Н-α- orientation were yielded, separated and identified using modern physical-chemical and spectral methods (13С NMR).

  15. hERG Blockade by Iboga Alkaloids.

    Science.gov (United States)

    Alper, Kenneth; Bai, Rong; Liu, Nian; Fowler, Steven J; Huang, Xi-Ping; Priori, Silvia G; Ruan, Yanfei

    2016-01-01

    The iboga alkaloids are a class of naturally occurring and synthetic compounds, some of which modify drug self-administration and withdrawal in humans and preclinical models. Ibogaine, the prototypic iboga alkaloid that is utilized clinically to treat addictions, has been associated with QT prolongation, torsades de pointes and fatalities. hERG blockade as IKr was measured using the whole-cell patch clamp technique in HEK 293 cells. This yielded the following IC50 values: ibogaine manufactured by semisynthesis via voacangine (4.09 ± 0.69 µM) or by extraction from T. iboga (3.53 ± 0.16 µM); ibogaine's principal metabolite noribogaine (2.86 ± 0.68 µM); and voacangine (2.25 ± 0.34 µM). In contrast, the IC50 of 18-methoxycoronaridine, a product of rational synthesis and current focus of drug development was >50 µM. hERG blockade was voltage dependent for all of the compounds, consistent with low-affinity blockade. hERG channel binding affinities (K i) for the entire set of compounds, including 18-MC, ranged from 0.71 to 3.89 µM, suggesting that 18-MC binds to the hERG channel with affinity similar to the other compounds, but the interaction produces substantially less hERG blockade. In view of the extended half-life of noribogaine, these results may relate to observations of persistent QT prolongation and cardiac arrhythmia at delayed intervals of days following ibogaine ingestion. The apparent structure-activity relationships regarding positions of substitutions on the ibogamine skeleton suggest that the iboga alkaloids might provide an informative paradigm for investigation of the structural biology of the hERG channel.

  16. [Non-alkaloid constituents of Gelsemium elegans].

    Science.gov (United States)

    Zhang, Binfeng; Chou, Guixin; Wang, Zhengtao

    2009-09-01

    To study the non-alkaloid chemical constituents of Gelsemium elegans. Compounds were isolated and purified by repeated column chromatography, and their structures were elucidated by spectroscopic methods. Ten compounds were isolated and their structures were identified as tamarixin (1), tamarixetin 3-O-beta-D-galactopyranoside (2), scopolin (3), scopoletin (4), uradine (5), caffeic acid (6), caffeic acid ethyl ester (7), ferulic acid ethyl ester (8), ethyl-alpha-D-fructofuranoside (9), and ethyl-beta-D-fructopyranoside (10). Compounds 1-3,5-10 are firstly isolated from this plant and compounds 1, 2, and 5-10 are isolated from the genus Gelsemium for the first time.

  17. New ester alkaloids from lupins (genus lupinus).

    Science.gov (United States)

    Mühlbauer, P; Witte, L; Wink, M

    1988-06-01

    Esters of 13-hydroxylupanine and 4-hydroxylupanine with acetic, propionic, butyric, isobutyric, valeric, isovaleric, tiglic, benzoic, and TRANS-cinnamic acid have been synthesized and characterized by capillary gas-liquid chromatography and mass spectrometry (EI-MS, CI-MS). In LUPINUS POLYPHYLLUS, L. ALBUS, L. ANGUSTIFOLIUS, and L. MUTABILIS we could identify new ester alkaloids (e.g. 13-propyloxylupanine, 13-butyryloxylupanine, 13-isobutyryloxylupanine, and 4-tigloyloxylupanine) besides the known esters, i.e. 13-acetoxylupanine, 13-isovaleroyloxylupanine, 13-angeloyloxylupanine, 13-tigloyloxylupanine, 13-benzoyloxylupanine, 13- CIS-cinnamoyloxylupanine nine, and 13- TRANS-cinnamoyloxylupanine.

  18. A new pyrroloquinazoline alkaloid from Linaria vulgaris.

    Science.gov (United States)

    Hua, Huiming; Cheng, Maosheng; Li, Xian; Pei, Yuehu

    2002-10-01

    A new alkaloid, 1,2,3,9-tetrahydropyrrolo(2,1-b)quinazolin-1-carboxylic acid (1), together with eight known compounds, 7-hydroxy vasicine (2), benzyl alcohol beta-D-(2'-O-beta-xylopyranosyl)glucopyranoside (3), benzyl alcohol O-beta-D-glucopyranoside (4), benzyl alcohol O-beta-D-primveroside (5), 3,5-dimethyl-4-hydroxy benzaldehyde (6), gluco-syringic acid (7), syringin (8), and liriodendrin (9), were isolated from the plants of Linaria vulgaris. Their structures were established by spectroscopic methods.

  19. Chromone and Flavonoid Alkaloids: Occurrence and Bioactivity

    Directory of Open Access Journals (Sweden)

    Robin J. Marles

    2011-12-01

    Full Text Available The chromone and flavonoid alkaloids represent an unusual group of structurally diverse secondary metabolites, derived from the convergence of multiple biosynthetic pathways that are widely distributed through the plant and animal kingdoms. Many of them have been discovered through bioassay-guided chemical investigations of traditional medicines, suggesting potential therapeutic significance. Their unique structures and varied pharmacological activities may provide important new leads for the discovery of drugs with novel mechanisms of action. Potential therapeutic indications are as diverse as cancer and viral infections, inflammation and immunomodulation, neurological and psychiatric conditions, and diabetes.

  20. Alkaloids from Piper sarmentosum and Piper nigrum.

    Science.gov (United States)

    Ee, G C L; Lim, C M; Lim, C K; Rahmani, M; Shaari, K; Bong, C F J

    2009-01-01

    Detailed chemical studies on the roots of Piper sarmentosum and Piper nigrum have resulted in several alkaloids. The roots of P. sarmentosum gave a new aromatic compound, 1-nitrosoimino-2,4,5-trimethoxybenzene (1). Piper nigrum roots gave pellitorine (2), (E)-1-[3',4'-(methylenedioxy)cinnamoyl]piperidine (3), 2,4-tetradecadienoic acid isobutyl amide (4), piperine (5), sylvamide (6), cepharadione A (7), piperolactam D (8) and paprazine (9). Structural elucidation of these compounds was achieved through NMR and MS techniques. Cytotoxic activity screening of the plant extracts indicated some activity.

  1. Monomeric carbohydrates production from olive tree pruning biomass: modeling of dilute acid hydrolysis.

    Science.gov (United States)

    Puentes, Juan G; Mateo, Soledad; Fonseca, Bruno G; Roberto, Inês C; Sánchez, Sebastián; Moya, Alberto J

    2013-12-01

    Statistical modeling and optimization of dilute sulfuric acid hydrolysis of olive tree pruning biomass has been performed using response surface methodology. Central composite rotatable design was applied to assess the effect of acid concentration, reaction time and temperature on efficiency and selectivity of hemicellulosic monomeric carbohydrates to d-xylose. Second-order polynomial model was fitted to experimental data to find the optimum reaction conditions by multiple regression analysis. The monomeric d-xylose recovery 85% (as predicted by the model) was achieved under optimized hydrolysis conditions (1.27% acid concentration, 96.5°C and 138 min), confirming the high validity of the developed model. The content of d-glucose (8.3%) and monosaccharide degradation products (0.1% furfural and 0.04% 5-hydroxymethylfurfural) provided a high quality subtract, ready for subsequent biochemical conversion to value-added products.

  2. The Roles of Monomeric GTP-Binding Proteins in Macroautophagy in Saccharomyces cerevisiae

    Directory of Open Access Journals (Sweden)

    Shu Yang

    2014-10-01

    Full Text Available Autophagy is a cellular degradation process that sequesters components into a double-membrane structure called the autophagosome, which then fuses with the lysosome or vacuole for hydrolysis and recycling of building blocks. Bulk phase autophagy, also known as macroautophagy, controlled by specific Atg proteins, can be triggered by a variety of stresses, including starvation. Because autophagy relies extensively on membrane traffic to form the membranous structures, factors that control membrane traffic are essential for autophagy. Among these factors, the monomeric GTP-binding proteins that cycle between active and inactive conformations form an important group. In this review, we summarize the functions of the monomeric GTP-binding proteins in autophagy, especially with reference to experiments in Saccharomyces cerevisiae.

  3. Multistage modeling of protein dynamics with monomeric Myc oncoprotein as an example

    Science.gov (United States)

    Liu, Jiaojiao; Dai, Jin; He, Jianfeng; Niemi, Antti J.; Ilieva, Nevena

    2017-03-01

    We propose to combine a mean-field approach with all-atom molecular dynamics (MD) into a multistage algorithm that can model protein folding and dynamics over very long time periods yet with atomic-level precision. As an example, we investigate an isolated monomeric Myc oncoprotein that has been implicated in carcinomas including those in colon, breast, and lungs. Under physiological conditions a monomeric Myc is presumed to be an example of intrinsically disordered proteins that pose a serious challenge to existing modeling techniques. We argue that a room-temperature monomeric Myc is in a dynamical state, it oscillates between different conformations that we identify. For this we adopt the C α backbone of Myc in a crystallographic heteromer as an initial ansatz for the monomeric structure. We construct a multisoliton of the pertinent Landau free energy to describe the C α profile with ultrahigh precision. We use Glauber dynamics to resolve how the multisoliton responds to repeated increases and decreases in ambient temperature. We confirm that the initial structure is unstable in isolation. We reveal a highly degenerate ground-state landscape, an attractive set towards which Glauber dynamics converges in the limit of vanishing ambient temperature. We analyze the thermal stability of this Glauber attractor using room-temperature molecular dynamics. We identify and scrutinize a particularly stable subset in which the two helical segments of the original multisoliton align in parallel next to each other. During the MD time evolution of a representative structure from this subset, we observe intermittent quasiparticle oscillations along the C-terminal α helix, some of which resemble a translating Davydov's Amide-I soliton. We propose that the presence of oscillatory motion is in line with the expected intrinsically disordered character of Myc.

  4. Fine blood vascular casting by monomeric methacrylate injection and microwave treatment

    OpenAIRE

    日根野谷, 仁

    1992-01-01

    A modified injection replica SEM method was introduced. Thorough injection of a resin mixture (monomeric metacrylate containing 1% benzoyl peroxide and 1% N, N-dimethylaniline) prior to the microwave treatment prepares good and fine blood vascular casts or replicas of brain, hypophysis, pineal body, thyroid gland and other organs. These casts sufficiently withstood ionbombardment and were useful for scanning electron microscopy. In this casting, preliminary perfusion fixation prior to the res...

  5. Effects of antibacterial agents on in vitro ovine ruminal biotransformation of the hepatotoxic pyrrolizidine alkaloid jacobine.

    OpenAIRE

    1992-01-01

    Ingestion of pyrrolizidine alkaloids, naturally occurring plant toxins, causes illness and death in a number of animal species. Senecio jacobaea pyrrolizidine alkaloids cause significant economic losses due to livestock poisoning, particularly in the Pacific Northwest. Some sheep are resistant to pyrrolizidine alkaloid poisoning, because ovine ruminal biotransformation detoxifies free pyrrolizidine alkaloids in digesta. Antibacterial agents modify ruminal fermentation. Pretreatment with antib...

  6. Heteroexpression and characterization of a monomeric isocitrate dehydrogenase from the multicellular prokaryote Streptomyces avermitilis MA-4680.

    Science.gov (United States)

    Wang, Ao; Cao, Zheng-Yu; Wang, Peng; Liu, Ai-Min; Pan, Wei; Wang, Jie; Zhu, Guo-Ping

    2011-08-01

    A monomeric NADP-dependent isocitrate dehydrogenase from the multicellular prokaryote Streptomyces avermitilis MA-4680 (SaIDH) was heteroexpressed in Escherichia coli, and the His-tagged enzyme was further purified to homogeneity. The molecular weight of SaIDH was about 80 kDa which is typical for monomeric isocitrate dehydrogenases. Structure-based sequence alignment reveals that the deduced amino acid sequence of SaIDH shows high sequence identity with known momomeric isocitrate dehydrogenase, and the coenzyme, substrate and metal ion binding sites are completely conserved. The optimal pH and temperature of SaIDH were found to be pH 9.4 and 45°C, respectively. Heat-inactivation studies showed that heating for 20 min at 50°C caused a 50% loss in enzymatic activity. In addition, SaIDH was absolutely specific for NADP+ as electron acceptor. Apparent Km values were 4.98 μM for NADP+ and 6,620 μM for NAD+, respectively, using Mn2+ as divalent cation. The enzyme performed a 33,000-fold greater specificity (kcat/Km) for NADP+ than NAD+. Moreover, SaIDH activity was entirely dependent on the presence of Mn2+ or Mg2+, but was strongly inhibited by Ca2+ and Zn2+. Taken together, our findings implicate the recombinant SaIDH is a divalent cation-dependent monomeric isocitrate dehydrogenase which presents a remarkably high cofactor preference for NADP+.

  7. Two mechanisms for dissipation of excess light in monomeric and trimeric light-harvesting complexes

    Energy Technology Data Exchange (ETDEWEB)

    Dall' Osto, Luca [Univ. di Verona, Verona (Italy). Dipartimento di Biotecnologie; Cazzaniga, Stefano [Univ. di Verona, Verona (Italy). Dipartimento di Biotecnologie; Bressan, Mauro [Univ. di Verona, Verona (Italy). Dipartimento di Biotecnologie; Paleček, David [Lund Univ. (Sweden). Dept. of Chemical Physics; Židek, Karel [Lund Univ. (Sweden). Dept. of Chemical Physics; Niyogi, Krishna K. [Univ. of California, Berkeley, CA (United States). Howard Hughes Medical Inst., Dept. of Plant and Microbial Biology; Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Division; Fleming, Graham R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Molecular Biophysics and Integrated Bioimaging Division; Univ. of California, Berkeley, CA (United States). Dept. of Chemistry, Graduate Group in Applied Science and Technology; Zigmantas, Donatas [Lund Univ. (Sweden). Dept. of Chemical Physics; Bassi, Roberto [Univ. di Verona, Verona (Italy). Dipartimento di Biotecnologie; Consiglio Nazionale delle Ricerche (CNR), Firenze (Italy). Istituto per la Protezione delle Piante (IPP)

    2017-04-10

    Oxygenic photoautotrophs require mechanisms for rapidly matching the level of chlorophyll excited states from light harvesting with the rate of electron transport from water to carbon dioxide. These photoprotective reactions prevent formation of reactive excited states and photoinhibition. The fastest response to excess illumination is the so-called non-photochemical quenching which, in higher plants, requires the luminal pH sensor PsbS and other yet unidentified components of the photosystem II antenna. Both trimeric light-harvesting complex II (LHCII) and monomeric LHC proteins have been indicated as site(s) of the heat-dissipative reactions. Different mechanisms have been proposed: Energy transfer to a lutein quencher in trimers, formation of a zeaxanthin radical cation in monomers. Here, we report on the construction of a mutant lacking all monomeric LHC proteins but retaining LHCII trimers. Its non-photochemical quenching induction rate was substantially slower with respect to the wild type. A carotenoid radical cation signal was detected in the wild type, although it was lost in the mutant. Here, we conclude that non-photochemical quenching is catalysed by two independent mechanisms, with the fastest activated response catalysed within monomeric LHC proteins depending on both zeaxanthin and lutein and on the formation of a radical cation. Trimeric LHCII was responsible for the slowly activated quenching component whereas inclusion in supercomplexes was not required. Finally, this latter activity does not depend on lutein nor on charge transfer events, whereas zeaxanthin was essential.

  8. Peracetic Acid Depolymerization of Biorefinery Lignin for Production of Selective Monomeric Phenolic Compounds.

    Science.gov (United States)

    Ma, Ruoshui; Guo, Mond; Lin, Kuan-Ting; Hebert, Vincent R; Zhang, Jinwen; Wolcott, Michael P; Quintero, Melissa; Ramasamy, Karthikeyan K; Chen, Xiaowen; Zhang, Xiao

    2016-07-25

    Lignin is the largest source of renewable material with an aromatic skeleton. However, due to the recalcitrant and heterogeneous nature of the lignin polymer, it has been a challenge to effectively depolymerize lignin and produce high-value chemicals with high selectivity. In this study, a highly efficient lignin-to-monomeric phenolic compounds (MPC) conversion method based on peracetic acid (PAA) treatment was reported. PAA treatment of two biorefinery lignin samples, diluted acid pretreated corn stover lignin (DACSL) and steam exploded spruce lignin (SESPL), led to complete solubilization and production of selective hydroxylated monomeric phenolic compounds (MPC-H) and monomeric phenolic acid compounds (MPC-A) including 4-hydroxy-2-methoxyphenol, p-hydroxybenzoic acid, vanillic acid, syringic acid, and 3,4-dihydroxybenzoic acid. The maximized MPC yields obtained were 18 and 22 % based on the initial weight of the lignin in SESPL and DACSL, respectively. However, we found that the addition of niobium pentoxide catalyst to PAA treatment of lignin can significantly improve the MPC yields up to 47 %. The key reaction steps and main mechanisms involved in this new lignin-to-MPC valorization pathway were investigated and elucidated.

  9. Peracetic Acid Depolymerization of Biorefinery Lignin for Production of Selective Monomeric Phenolic Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Ruoshui [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Guo, Mond [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Lin, Kuan-ting [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Hebert, Vincent R. [Food and Environmental Laboratory, Washington State, University-TriCities, 2710 Crimson Way Richland WA 99354 USA; Zhang, Jinwen [Wood Materials and Engineering Laboratory, Washington State University, Pullman WA 99164 USA; Wolcott, Michael P. [Wood Materials and Engineering Laboratory, Washington State University, Pullman WA 99164 USA; Quintero, Melissa [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Ramasamy, Karthikeyan K. [Chemical and Biological Process Development Group, Pacific Northwest National Laboratory, Richland WA 99354 USA; Chen, Xiaowen [National Bioenergy Center, National Renewable Energy Lab, 1617 Cole Blvd Golden CO 80127 USA; Zhang, Xiao [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA

    2016-07-04

    Lignin is the largest source of renewable material with an aromatic skeleton. However, due to the recalcitrant and heterogeneous nature of the lignin polymer as well as its complex side chain structures, it has been a challenge to effectively depolymerize lignin and produce high value chemicals with high selectivity. In this study, a highly efficient lignin-to-monomeric phenolic compounds (MPC) conversion method based on peracetic acid (PAA) treatment was reported. PAA treatment of two biorefinery lignin samples, diluted acid pretreated corn stover lignin (DACSL) and steam exploded spruce lignin (SESPL), led to complete solubilization and production of selective hydroxylated monomeric phenolic compounds (MPC-H) and monomeric phenolic acid compounds (MPC-A) inclduing 4-hydroxy-2-methoxyphenol, p-hydroxybenzoic acid, vanillic acid, syringic acid, and 3,4-dihydroxybenzoic acid. The maximized MPCs yields obtained were 18% and 22% based on the initial weight of the lignin in SESPL and DACSL respectively. However, we found that the addition of niobium pentoxide catalyst to PAA treatment of lignin can significantly improve the MPC yields up to 47%. The key reaction steps and main mechanisms involved in this new lignin-to-MPC valorization pathway were investigated and elucidated.

  10. Peracetic Acid Depolymerization of Biorefinery Lignin for Production of Selective Monomeric Phenolic Compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Ruoshui [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Guo, Mond [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Lin, Kuan-ting [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Hebert, Vincent R. [Food and Environmental Laboratory, Washington State, University-TriCities, 2710 Crimson Way Richland WA 99354 USA; Zhang, Jinwen [Wood Materials and Engineering Laboratory, Washington State University, Pullman WA 99164 USA; Wolcott, Michael P. [Wood Materials and Engineering Laboratory, Washington State University, Pullman WA 99164 USA; Quintero, Melissa [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA; Ramasamy, Karthikeyan K. [Chemical and Biological Process Development Group, Pacific Northwest National Laboratory, Richland WA 99354 USA; Chen, Xiaowen [National Bioenergy Center, National Renewable Energy Lab, 1617 Cole Blvd Golden CO 80127 USA; Zhang, Xiao [Voiland School of Chemical Engineering and Bioengineering, Bioproducts, Science & Engineering Laboratory, Washington State University, 2710 Crimson Way Richland WA 99354 USA

    2016-07-04

    Lignin is the largest source of renewable material with an aromatic skeleton. However, due to the recalcitrant and heterogeneous nature of the lignin polymer, it has been a challenge to effectively depolymerize lignin and produce high-value chemicals with high selectivity. In this study, a highly efficient lignin-to-monomeric phenolic compounds (MPC) conversion method based on peracetic acid (PAA) treatment was reported. PAA treatment of two biorefinery lignin samples, diluted acid pretreated corn stover lignin (DACSL) and steam exploded spruce lignin (SESPL), led to complete solubilization and production of selective hydroxylated monomeric phenolic compounds (MPC-H) and monomeric phenolic acid compounds (MPC-A) including 4-hydroxy-2-methoxyphenol, p-hydroxybenzoic acid, vanillic acid, syringic acid, and 3,4-dihydroxybenzoic acid. The maximized MPC yields obtained were 18 and 22 % based on the initial weight of the lignin in SESPL and DACSL, respectively. However, we found that the addition of niobium pentoxide catalyst to PAA treatment of lignin can significantly improve the MPC yields up to 47 %. The key reaction steps and main mechanisms involved in this new lignin-to-MPC valorization pathway were investigated and elucidated.

  11. First synthesis and structural determination of a monomeric, unsolvated lithium amide, LiNH(2).

    Science.gov (United States)

    Grotjahn, D B; Sheridan, P M; Al Jihad, I; Ziurys, L M

    2001-06-13

    Alkali metal amides typically aggregate in solution and the solid phase, and even in the gas phase. In addition, even in the few known monomeric structures, the coordination number of the alkali metal is raised by binding of Lewis-basic solvent molecules, with concomitant changes in structure. In contrast, the simplest lithium amide LiNH(2) has never been made in a monomeric form, even though its structure has been theoretically predicted several times. Here, the first experimental structural data for a monomeric, unsolvated lithium amide are determined using a combination of gas-phase synthesis and millimeter/submillimeter-wave spectroscopy. All data point to a planar structure for LiNH(2). The r(o) structure of LiNH(2) has a Li-N distance of 1.736(3) A, an N-H distance of 1.022(3) A, and a H-N-H angle of 106.9(1) degrees. These results are compared with theoretical predictions for LiNH(2), and experimental data for oligomeric, solid-phase samples, which could not resolve the question of whether LiNH(2) is planar or not. In addition, comparisons are made with revised gas-phase and solid-phase data and calculated structures of NaNH(2).

  12. The peroxisomal protein import machinery displays a preference for monomeric substrates.

    Science.gov (United States)

    Freitas, Marta O; Francisco, Tânia; Rodrigues, Tony A; Lismont, Celien; Domingues, Pedro; Pinto, Manuel P; Grou, Cláudia P; Fransen, Marc; Azevedo, Jorge E

    2015-04-01

    Peroxisomal matrix proteins are synthesized on cytosolic ribosomes and transported by the shuttling receptor PEX5 to the peroxisomal membrane docking/translocation machinery, where they are translocated into the organelle matrix. Under certain experimental conditions this protein import machinery has the remarkable capacity to accept already oligomerized proteins, a property that has heavily influenced current models on the mechanism of peroxisomal protein import. However, whether or not oligomeric proteins are really the best and most frequent clients of this machinery remain unclear. In this work, we present three lines of evidence suggesting that the peroxisomal import machinery displays a preference for monomeric proteins. First, in agreement with previous findings on catalase, we show that PEX5 binds newly synthesized (monomeric) acyl-CoA oxidase 1 (ACOX1) and urate oxidase (UOX), potently inhibiting their oligomerization. Second, in vitro import experiments suggest that monomeric ACOX1 and UOX are better peroxisomal import substrates than the corresponding oligomeric forms. Finally, we provide data strongly suggesting that although ACOX1 lacking a peroxisomal targeting signal can be imported into peroxisomes when co-expressed with ACOX1 containing its targeting signal, this import pathway is inefficient.

  13. Treatment of iron deficiency anemia: are monomeric iron compounds suitable for parenteral administration?

    Science.gov (United States)

    Gupta, A; Crumbliss, A L

    2000-11-01

    Iron deficiency is the most common nutritional problem worldwide, especially in the developing countries. Oral iron supplementation programs have failed because of noncompliance and gastrointestinal toxicity, thereby necessitating parenteral administration of iron. For parenteral administration, only iron-carbohydrate complexes are currently used, because monomeric iron salts release free iron, thereby causing oxidant injury. However, iron-carbohydrate complexes also have significant toxicity, and they are expensive. We have proposed the hypothesis that monomeric iron salts can be safely administered by the parenteral route if iron is tightly complexed to the ligand, thereby causing clinically insignificant release of free iron, and the kinetic properties of the compound allow rapid transfer of iron to plasma transferrin. A detailed analysis of the physicochemical and kinetic properties reveals that ferric iron complexed to pyrophosphate or acetohydroxamate anions may be suitable for parenteral administration. We have demonstrated that infusion of ferric pyrophosphate into the circulation via the dialysate is safe and effective in maintaining iron balance in patients undergoing maintenance hemodialysis. Parenteral administration of monomeric iron compounds is a promising approach to the treatment of iron deficiency in the general population and merits further investigation.

  14. Cardiovascular pharmacological effects of bisbenzylisoquinoline alkaloid derivatives.

    Science.gov (United States)

    Qian, Jia-Qing

    2002-12-01

    Tetrandrine, dauricine, daurisoline and neferine are bisbenzylisoquinoline alkaloid derivatives isolated from Chinese traditional medicine and herbs. The cardiovascular pharmacological effects and the mechanism of actions of these compounds were reviewed. Tetrandrine isolated from Stephania tetrandra S Moore possesses antihypertensive and antiarrhythmic effects. The antihypertensive effects of tetrandrine have been demonstrated in experimental hypertensive animals and in hypertensive patients. Recent studies showed that in addition to its calcium antagonistic effect, tetrandrine interacted with M receptors. Modulation by M receptor is one of the pharmacological mechanisms of cardiovascular effects of tetrandrine. Dauricine and daurisoloine were isolated from Menispermum dauricum DC. The antiarrhythmic effects of dauricine have been verified in different experimental arrhythmic models and in cardiac arrhythmic patients. Dauricine blocked the cardiac transmembrane Na+,K+ and Ca2+ ion currents. Differing from quinidine and sotalol, which exhibited reverse use-dependent effect, dauricine prolonged APD in a normal use-dependent manner in experimental studies. The antiarrhythmic effect of daurisoline and neferine which is an alkaloid isolated from Nelumbo nucifera Gaertn, and their mechanisms of actions have also been studied. The antiarrhythmic effect of daurisoline is more potent than that of dauricine.

  15. Neurotoxic Alkaloids: Saxitoxin and Its Analogs

    Directory of Open Access Journals (Sweden)

    Troco K. Mihali

    2010-07-01

    Full Text Available Saxitoxin (STX and its 57 analogs are a broad group of natural neurotoxic alkaloids, commonly known as the paralytic shellfish toxins (PSTs. PSTs are the causative agents of paralytic shellfish poisoning (PSP and are mostly associated with marine dinoflagellates (eukaryotes and freshwater cyanobacteria (prokaryotes, which form extensive blooms around the world. PST producing dinoflagellates belong to the genera Alexandrium, Gymnodinium and Pyrodinium whilst production has been identified in several cyanobacterial genera including Anabaena, Cylindrospermopsis, Aphanizomenon Planktothrix and Lyngbya. STX and its analogs can be structurally classified into several classes such as non-sulfated, mono-sulfated, di-sulfated, decarbamoylated and the recently discovered hydrophobic analogs—each with varying levels of toxicity. Biotransformation of the PSTs into other PST analogs has been identified within marine invertebrates, humans and bacteria. An improved understanding of PST transformation into less toxic analogs and degradation, both chemically or enzymatically, will be important for the development of methods for the detoxification of contaminated water supplies and of shellfish destined for consumption. Some PSTs also have demonstrated pharmaceutical potential as a long-term anesthetic in the treatment of anal fissures and for chronic tension-type headache. The recent elucidation of the saxitoxin biosynthetic gene cluster in cyanobacteria and the identification of new PST analogs will present opportunities to further explore the pharmaceutical potential of these intriguing alkaloids.

  16. Alkaloid toxins in endophyte-infected grasses.

    Science.gov (United States)

    Powell, R G; Petroski, R J

    1992-01-01

    Grasses infected with clavicipitaceous fungi have been associated with a variety of diseases including classical ergotism in humans and animals, fescue foot and summer syndrome in cattle, and rye-grass staggers in sheep. During the last decade it has been recognized that many of these fungal infections are endophytic; a fungal endophyte is a fungus that grows entirely within the host plant. Inspection of field collections and herbarium specimens has revealed that such infections are widespread in grasses. The chemistry associated with these grass-fungal interactions has proved to be interesting and complex, as each grass-fungal pair results in a unique "fingerprint" of various alkaloids, of which some are highly toxic to herbivores. In many cases the presence of an endophyte appears to benefit the plant by increasing drought resistance, or by increasing resistance to attack by insects, thus improving the overall survivability of the grass. This review will focus on alkaloids that have been reported in endophyte-infected grasses.

  17. Induction of antibodies against epitopes inaccessible on the HIV type 1 envelope oligomer by immunization with recombinant monomeric glycoprotein 120

    DEFF Research Database (Denmark)

    Schønning, Kristian; Bolmstedt, A; Novotny, J;

    1998-01-01

    An N-glycan (N306) at the base of the V3 loop of HIV-BRU gp120 is shielding a linear neutralization epitope at the tip of the V3 loop on oligomeric Env. In contrast, this epitope is readily antigenic on monomeric gp120. Immunization with recombinant monomeric HIV-BRU gp120 may thus be expected to...... immunogenic structures inaccessible on the envelope oligomer. The limited ability of recombinant gp120 vaccines to induce neutralizing antibodies against primary isolates may thus not exclusively reflect genetic variation.......An N-glycan (N306) at the base of the V3 loop of HIV-BRU gp120 is shielding a linear neutralization epitope at the tip of the V3 loop on oligomeric Env. In contrast, this epitope is readily antigenic on monomeric gp120. Immunization with recombinant monomeric HIV-BRU gp120 may thus be expected...

  18. A new cytotoxic carbazole alkaloid and two new other alkaloids from Clausena excavata.

    Science.gov (United States)

    Peng, Wen-Wen; Zeng, Guang-Zhi; Song, Wei-Wu; Tan, Ning-Hua

    2013-07-01

    One new carbazole alkaloid, excavatine A (1), and two additional new alkaloids, excavatine B (2) and excavatine C (3), were isolated from the stems and leaves of Clausena excavata Burm.f. (Rutaceae). Their structures were determined on the basis of detailed spectroscopic analyses, especially 2D-NMR and HR-EI-MS data. Compounds 1-3 were tested for their cytotoxic activities against A549, HeLa, and BGC-823 cancer cell lines, and for their antimicrobial activities against Candida albicans and Staphylococcus aureus. Only 1 exhibited cytotoxicity against A549 and HeLa cell lines with the IC50 values of 5.25 and 1.91 μg/ml, respectively.

  19. Indolopyridoquinazoline alkaloids from Esenbeckia grandiflora mart. (Rutaceae); Alkaloides {beta}-indolopiridoquinazolinicos de Esenbeckia grandiflora mart. (Rutaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Januario, Ana Helena; Vieira, Paulo Cezar; Silva, Maria Fatima das Gracas Fernandes da; Fernandes, Joao Batista [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica], e-mail: anahjanuario@unifran.br; Silva, Jorge Jose de Brito; Conserva, Lucia Maria [Universidade Federal de Alagoas (UFAL), Maceio, AL (Brazil). Inst. de Quimica e Biotecnologia

    2009-07-01

    The chemical composition of two specimens of Esenbeckia grandiflora, collected in the south and northeast regions of Brazil, was investigated. In this study, three b-indolopyridoquinazoline alkaloids from the leaves (rutaecarpine, 1-hydroxyrutaecarpine) and roots (euxylophoricine D) were isolated for the first time in this genus. In addition, the triterpenes {alpha}-amyrin, {beta}-amyrin, {alpha}-amyrenonol, {beta}-amyrenonol, 3{alpha}-hydroxy-ursan-12-one, and 3{alpha}-hydroxy-12,13-epoxy-oleanane, the coumarins auraptene, umbelliferone, pimpinelin, and xanthotoxin, the furoquinoline alkaloids delbine and kokusaginine, and the phytosteroids sitosterol, stigmasterol, campesterol and 3{beta}-O-{beta}-D-glucopyranosylsitosterol were also isolated from the leaves, twigs, roots and stems of this species. Structures of these compounds were established by spectral analysis. (author)

  20. [A new alkaloid from Menispermum dauricum DC--N-desmethyldauricine].

    Science.gov (United States)

    Pan, X P

    1992-01-01

    A new phenolic dauricine-type alkaloid together with the know dauricine were isolated from the rhizoma of Menispermum dauricum DC cultivated in Xianning district, Hubei province. Dauricine was obtained as the major alkaloid and was confirmed by comparison with authentic sample. The new alkaloid is an unstable white powder: Based on spectrometric analysis (UV, IR, FAB-MS and 1HNMR) and N-methylation which offered dauricine dimethiodide (V), the structure was elucidated as RR, N-desmethyldauricine (II), which was isolated for the first time from nature.

  1. Prenylindole alkaloids from Raputia praetermissa (Rutaceae) and their chemosystematic significance

    Energy Technology Data Exchange (ETDEWEB)

    Rosas, Lisandra V.; Veiga, Thiago Andre M.; Fernandes, Joao B.; Vieira, Paulo C.; Silva, M. Fatima das G.F. da, E-mail: dmfs@power.ufscar.b [Universidade Federal de Sao Carlos (DQ/UFSCar), SP (Brazil). Dept. de Quimica

    2011-07-01

    The dichloromethane extract from the stems of Raputia praetermissa afforded four new compounds, 4-deoxyraputindole C (1), raputimonoindole A-B (2, 3), and hexadecanyl 2-hydroxy- 4-methoxy-cinnamate (5), besides the alkaloids 5-(4-methoxymethylfuran-2-yl)-1H-indole (raputimonoindole C), furoquinolines maculosidine, robustine, evolitrine and dictamnine. The hexane extract yielded N-methyl-4-methoxyquinoline-2(1H)-one, skimmianine, cycloartenone, sitosterol, stigmasterol and sitostenone. The anthranilate alkaloid content indicates that the genus is strongly related to those included in Cusparieae tribe, but differs from Neoraputia by the absence of prenylindole alkaloids in the late, whose species have previously been placed in Raputia. (author)

  2. γ-Lactam alkaloids from the flower buds of daylily.

    Science.gov (United States)

    Matsumoto, Takahiro; Nakamura, Seikou; Nakashima, Souichi; Ohta, Tomoe; Yano, Mamiko; Tsujihata, Junichiro; Tsukioka, Junko; Ogawa, Keiko; Fukaya, Masashi; Yoshikawa, Masayuki; Matsuda, Hisashi

    2016-07-01

    Four new alkaloids, hemerocallisamines IV-VII, were isolated from the methanol extract of flower buds of daylily. The chemical structures of the new compounds were elucidated on the basis of chemical and physicochemical evidence. The absolute stereochemistry of the hemerocallisamines IV-VI was elucidated by the application of the modified Mosher's method, HPLC analysis, and optical rotation. In the present study, the isolated alkaloids significantly inhibited the aggregation of Aβ42 in vitro. This is the first report about bioactive alkaloids with a γ-lactam ring from daylily. In addition, isolated nucleosides showed accelerative effects on neurite outgrowth under the non-fasting condition.

  3. Qualitative determination of indole alkaloids of Tabernaemontana fuchsiaefolia (Apocynaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Zocoler, Marcos A. [Universidade do Oeste Paulista, Presidente Prudente, SP (Brazil). Dept. de Farmacos e Medicamentos; Oliveira, Arildo J.B. de [Universidade Estadual de Maringa, PR (Brazil). Dept. de Farmacia e Farmacologia; Sarragiotto, Maria H.; Grzesiuk, Viviane L.; Vidotti, Gentil J. [Universidade Estadual de Maringa, PR (Brazil). Dept. de Quimica]. E-mail: gjvidotti@uem.br

    2005-11-15

    This p describes a fast and efficient procedure to separate and identify indole alkaloids from the ethanolic extract of Tabernaemontana fuchsiaefolia (Apocynaceae). The alkaloidal fractions obtained from ethanolic extracts of leaves and stem barks and root barks were fractioned and analyzed by Thin-Layer Chromatography (TLC) and by Gas Chromatography coupled to Mass Spectrometry (GC-MS). The following indole alkaloids were identified: ibogamine, coronaridine, ibogaine pseudoindoxyl, voacangine hydroxyindolenine, voacangine pseudoindoxyl, tabernanthine, catharanthine, voacangine, 19-oxovoacangine, 10-hydroxycoronaridine, affinisine, 16-epi-affinine, voachalotine, ibogaline, and conopharyngine. (author)

  4. Genotoxic and tumorigenic pyrrolizidine alkaloids in Chinese herbal plants

    Institute of Scientific and Technical Information of China (English)

    P.P. Fu; Q. Xia; M.W. Chou; G. Lin

    2005-01-01

    Pyrrolizidine alkaloids are a class of hepatotoxic and tumorigenic compounds detected in Chinese herbal plants,contaminated foods, and dietary supplements. In this review, the sources, toxicity, genotoxicity, tumorigenicity, and the metabolic pathways,particular the activation pathways leading to hepatotoxicity and tumorigenicity, of pyrrolizidine alkaloids are briefly discussed, with a focus on the most recent important findings concerning the genotoxic mechanism by which riddelliine liver tumors. This mechanism involves the formation of 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived DNA adducts and may be general to most carcinogenic pyrrolizidine alkaloids.

  5. Alkaloid content of the seeds from Erythroxylum Coca var. Coca.

    Science.gov (United States)

    Casale, John F; Toske, Steven G; Colley, Valerie L

    2005-11-01

    Alkaloid extracts from the seeds of Erythroxylum Coca var. Coca grown in the Chapare Valley of Bolivia were subjected to gas and liquid chromatographic-mass spectrometric analyses. Several alkaloids from these seeds were detected and characterized, including methylecgonidine, tropine, 3alpha-acetoxytropane, ecgonine methyl ester, cuscohygrine, N-norbenzoyltropine, benzoyltropine, hexanoylecgonine methyl ester, cocaine, cis-cinnamoylcocaine, and trans-cinnamoylcocaine. Methylecgonidine was determined to be the primary constituent and not an analytical artifact. Additionally, two significant new uncharacterized alkaloids were established as present. Recent evidence suggests that some cocaine processors are adding this seed extraction material to cocaine extracted from coca leaf and may impact cocaine impurity signature profiles.

  6. Cytotoxic alkaloids from stems, leaves and twigs of Dasymaschalon blumei.

    Science.gov (United States)

    Chanakul, Waraporn; Tuchinda, Patoomratana; Anantachoke, Natthinee; Pohmakotr, Manat; Piyachaturawat, Pawinee; Jariyawat, Surawat; Suksen, Kanoknetr; Jaipetch, Tharworn; Nuntasaen, Narong; Reutrakul, Vichai

    2011-10-01

    Bioassay-guided fractionation of the cytotoxic ethyl acetate extract from the stems of Dasymaschalon blumei (Annonaceae) led to the isolation of four aristololactam alkaloids, including the hitherto unknown 3,5-dihydroxy-2,4-dimethoxyaristolactam (1), as well as the three known compounds, aristolactam BI, goniopedaline, and griffithinam. Additionally, the cytotoxic extract from the combined leaves and twigs of the same plant yielded three known oxoaporphine alkaloids, oxodiscoguattine, dicentrinone, and duguevalline. The structures of aristolactams and oxoaporphine alkaloids were elucidated on the basis of spectroscopic methods. All isolates were evaluated for cytotoxicity against a panel of mammalian cancer cell lines and a noncancerous human embryonic kidney cell Hek 293.

  7. Investigation of Aconitine-type Alkaloids from Processed Tuber of Aconitum carmiechaeli by HPLC-ESI-MS/MSn

    Institute of Scientific and Technical Information of China (English)

    YUE Hao; PI Zi-feng; ZHAO Yu-feng; SONG Feng-rui; LIU Zhi-qiang; LIU Shu-ying

    2007-01-01

    @@ Introduction Aconitine-type alkaloids isolated from the roots of Aconitum carmiechaeli show a potential toxicity and a broad spectrum of bioactivity[1-4]. On the basis of the C8-substituent of C19-diterpenoid skeleton, aconitinetype alkaloids can be divided into diester-diterpenoid alkaloids( DDAs), monoester-diterpenoid alkaloids(MDAs), and lipo-alkaloids( Fig. 1 ).

  8. One new alkaloid from Chelidonium majus L.

    Science.gov (United States)

    Zhang, Wen-Juan; You, Chun-Xue; Wang, Cheng-Fang; Fan, Li; Wang, Ying; Su, Yang; Deng, Zhi-Wei; Du, Shu-Shan

    2014-01-01

    One new alkaloid, together with 10 known compounds were isolated from the aerial parts of Chelidonium majus L. by repeated silica gel column chromatography. Their chemical structures were elucidated on the basis of physicochemical and spectroscopic data. Among them, 6-acetonyldihydrochelerythrine (4), 6-acetonyldihydrosanguinarine (5), 6-ketenesanguinarine (6), demethylchelerythrine (7) and demethylsanguinarine (11) were isolated for the first time from this plant. Compound 6 was identified as a new compound. These compounds were screened for cytotoxicity against human non-small lung carcinoma (H1299), breast cancer (MCF-7) and liver cancer (SMMC-7721). In a series of cytotoxic tests, compounds 9 and 10 displayed potent cytotoxic activity against H1299, MCF-7 and SMMC-7721, with the IC50 values of 8.16-35.25 μg/mL.

  9. Anticancer Alkaloid Lamellarins Inhibit Protein Kinases

    Directory of Open Access Journals (Sweden)

    Laurent Meijer

    2008-10-01

    Full Text Available Lamellarins, a family of hexacyclic pyrrole alkaloids originally isolated from marine invertebrates, display promising anti-tumor activity. They induce apoptotic cell death through multi-target mechanisms, including inhibition of topoisomerase I, interaction with DNA and direct effects on mitochondria. We here report that lamellarins inhibit several protein kinases relevant to cancer such as cyclin-dependent kinases, dualspecificity tyrosine phosphorylation activated kinase 1A, casein kinase 1, glycogen synthase kinase-3 and PIM-1. A good correlation is observed between the effects of lamellarins on protein kinases and their action on cell death, suggesting that inhibition of specific kinases may contribute to the cytotoxicity of lamellarins. Structure/activity relationship suggests several paths for the optimization of lamellarins as kinase inhibitors.

  10. Tetrahydroberberine, a pharmacologically active naturally occurring alkaloid.

    Science.gov (United States)

    Pingali, Subramanya; Donahue, James P; Payton-Stewart, Florastina

    2015-04-01

    Tetrahydroberberine (systematic name: 9,10-dimethoxy-5,8,13,13a-tetrahydro-6H-benzo[g][1,3]benzodioxolo[5,6-a]quinolizine), C20H21NO4, a widely distributed naturally occurring alkaloid, has been crystallized as a racemic mixture about an inversion center. A bent conformation of the molecule is observed, with an angle of 24.72 (5)° between the arene rings at the two ends of the reduced quinolizinium core. The intermolecular hydrogen bonds that play an apparent role in crystal packing are 1,3-benzodioxole -CH2···OCH3 and -OCH3···OCH3 interactions between neighboring molecules.

  11. Antifouling Alkaloids from Crinum augustum (Amaryllidaceae

    Directory of Open Access Journals (Sweden)

    John Refaat

    2009-01-01

    Full Text Available Fractionation and purification of the ethanolic extract of the bulbs of Crinum augustum Rox. (Amaryllidaceae cultivated in Egypt yielded five alkaloids 6-methoxy-crinamine (1 , crinamine (2 , buphanisine (3 , ungeremine (4 , and hippadine (5 ; two fatty acid derivatives: myristic acid ethyl ester (6 and palmitic acid ethyl ester (7 ; four terpenoidal and steroidal compounds: ursolic acid (8 , β-sitosterol-O- β glucopyranoside (9 and mixture of β--sitosterol (10 and stigmasterol (11 . The structures of all compounds were determined by interpretation of their spectroscopic data; 1D ( 1 H and 13 C, 2D (HSQC, COSY, DQF, NOE and HMBC NMR; MS and UV analyses. The compounds (1 -4 and (6-8 were tested towards biofouling activity using larvae of barnacle Balance amphitrie. Significant activities of 1, 2 and 3 with EC 50 1.8, 1.2 and 0.75 μg/mL respectively, were observed.

  12. Pyrrolidonyl and pyridyl alkaloids in Lymantria dispar.

    Science.gov (United States)

    Deml, Reinhold

    2003-01-01

    The occurrence and metabolism of nicotine and related N-containing compounds in body fluids of the gipsy moth were addressed. Thin layer chromatographic studies clearly showed the simultaneous presence of GABA and 2-pyrrolidone but not of GABamide in the larval haemolymph and osmeterial secretion of Lymantria dispar as well as in the corresponding body fluids of the saturniids, Saturnia pavonia and Attacus atlas. Furthermore, feeding and injection experiments using alkylated precursors and combined gas chromatography/mass spectrometry gave evidence of the transformation of 2-pyrrolidone to nicotine and of nicotinic acid to nicotinamide in caterpillars of L. dispar. Based on these results, on the earlier described variation of the secondary-compound patterns of L. dispar during its development, and on literature data, metabolic pathways for the hitherto detected pyridyl and pyrrolidonyl alkaloids in Lymantriidae (and possibly Saturniidae) are proposed.

  13. Erythroidine alkaloids: a novel class of phytoestrogens.

    Science.gov (United States)

    Djiogue, Sefirin; Halabalaki, Maria; Njamen, Dieudonné; Kretzschmar, Georg; Lambrinidis, George; Hoepping, Josephine; Raffaelli, Francesca M; Mikros, Emmanuel; Skaltsounis, Alexios-Leandros; Vollmer, Günter

    2014-07-01

    Erythrina poeppigiana is a medicinal plant which is widely used in Asia, Latin America, and Africa in traditional remedies for gynecological complications and maladies. In continuation of studies for the discovery of novel phytoestrogens, four erythroidine alkaloids, namely α-erythroidine, β-erythroidine, and their oxo-derivatives 8-oxo-α-erythroidine and 8-oxo-β-erythroidine, were isolated and structurally characterized from the methanolic extract of the stem bark of E. poeppigiana. Due to the high amounts of erythroidines in the extract and considering the widespread utilization of Erythrina preparations in traditional medicine, the exploration of their estrogenic properties was performed. The estrogenicity of the isolated erythroidines was assayed in various estrogen receptor-(ER)-dependent test systems, including receptor binding affinity, cell culture based ER-dependent reporter gene assays, and gene expression studies in cultured cells using reverse transcription polymerase chain reaction techniques. α-Erythroidine and β-erythroidine showed binding affinity values for ERα of 0.015 ± 0.010% and 0.005 ± 0.010%, respectively, whereas only β-erythroidine bound to ERβ (0.006 ± 0.010%). In reporter gene assays, both erythroidines exhibited a significant dose-dependent estrogenic stimulation of ER-dependent reporter gene activity in osteosarcoma cells detectable already at 10 nM. Results were confirmed in the MVLN cells, a bioluminescent variant of MCF-7 breast cancer cells. Further, α-erythroidine and β-erythroidine both induced the enhanced expression of the specific ERα-dependent genes trefoil factor-1 and serum/glucocorticoid regulated kinase 3 in MCF-7 cells, confirming estrogenicity. Additionally, using molecular docking simulations, a potential mode of binding on ERα, is proposed, supporting the experimental evidences. This is the first time that an estrogenic profile is reported for erythroidine alkaloids, potentially a new class of

  14. Pyrrolizidine alkaloids in honey: comparison of analytical methods

    NARCIS (Netherlands)

    Kempf, M.; Wittig, M.; Reinhard, A.; Ohe, von der K.; Blacquière, T.; Raezke, K.P.; Michel, R.; Schreier, P.; Beuerle, T.

    2011-01-01

    Pyrrolizidine alkaloids (PAs) are a structurally diverse group of toxicologically relevant secondary plant metabolites. Currently, two analytical methods are used to determine PA content in honey. To achieve reasonably high sensitivity and selectivity, mass spectrometry detection is demanded. One me

  15. New bisbenzylisoquinoline alkaloid from Laureliopsis philippiana

    DEFF Research Database (Denmark)

    Stærk, Dan; Thi, Loi Pham; Rasmussen, Hasse Bonde;

    2009-01-01

    Phytochemical investigation of Laureliopsis philippiana resulted in isolation of a new bisbenzylisoquinoline alkaloid (1) named laureliopsine A. The structure was established by spectroscopic methods, including 2D homo- and heteronuclear NMR experiments. This finding of a bisbenzylisoquinoline al...

  16. New bromotyrosine alkaloids from the marine sponge Psammaplysilla purpurea

    Digital Repository Service at National Institute of Oceanography (India)

    Tilvi, S.; Rodrigues, C; Naik, C; Parameswaran, P.S.; Wahidullah, S.

    Seven new bromotyrosine alkaloids Purpurealidin A, B, C, D, F, G, H and the known compounds Purealidin Q, Purpurealidin E, 16-Debromoaplysamine-4 and Purpuramine I have been isolated from the marine sponge Psammaplysilla purpurea. Their structure...

  17. Arginine decarboxylase as the source of putrescine for tobacco alkaloids

    Science.gov (United States)

    Tiburcio, A. F.; Galston, A. W.

    1986-01-01

    The putrescine which forms a part of nicotine and other pyrrolidine alkaloids is generally assumed to arise through the action of ornithine decarboxylase (ODC). However, we have previously noted that changes in the activity of arginine decarboxylase (ADC), an alternate source of putrescine, parallel changes in tissue alkaloids, while changes in ODC activity do not. This led us to undertake experiments to permit discrimination between ADC and ODC as enzymatic sources of putrescine destined for alkaloids. Two kinds of evidence presented here support a major role for ADC in the generation of putrescine going into alkaloids: (a) A specific 'suicide inhibitor' of ADC effectively inhibits the biosynthesis of nicotine and nornicotine in tobacco callus, while the analogous inhibitor of ODC is less effective, and (b) the flow of 14C from uniformly labelled arginine into nicotine is much more efficient than that from ornithine.

  18. Alkaloids with Different Carbon Units from Myrioneuron faberi.

    Science.gov (United States)

    Cao, Ming-Ming; Zhang, Yu; Huang, Sheng-Dian; Di, Ying-Tong; Peng, Zong-Gen; Jiang, Jian-Dong; Yuan, Chun-Mao; Chen, Duo-Zhi; Li, Shun-Lin; He, Hong-Ping; Hao, Xiao-Jiang

    2015-11-25

    Three new Myrioneuron alkaloids, myrifamines A-C (1-3), with unique skeletons were isolated from Myrioneuron faberi. The absolute configuration of 1 was confirmed by single-crystal X-ray diffraction analysis, and the stereochemistry of the other two alkaloids was determined using a combination of ROESY experiments and calculated and experimental electronic circular dichroism spectra. Myrifamine C (3) is the first example of a symmetric dimer among the Myrioneuron alkaloids. Known alkaloids myrionamide (4) and schoberine (5) were also isolated, and experimental NMR and X-ray diffraction data suggest their structural revision. Compound 2 showed significant inhibitory activity toward the hepatitis C virus in vitro, with a therapeutic index (CC50/EC50) greater than 108.7.

  19. Microcalorimetry studies of the antimicrobial actions of Aconitum alkaloids.

    Science.gov (United States)

    Shi, Yan-bin; Liu, Lian; Shao, Wei; Wei, Ting; Lin, Gui-mei

    2015-08-01

    The metabolic activity of organisms can be measured by recording the heat output using microcalorimetry. In this paper, the total alkaloids in the traditional Chinese medicine Radix Aconiti Lateralis were extracted and applied to Escherichia coli and Staphylococcus aureus. The effect of alkaloids on bacteria growth was studied by microcalorimetry. The power-time curves were plotted with a thermal activity monitor (TAM) air isothermal microcalorimeter and parameters such as growth rate constant (μ), peak-time (Tm), inhibitory ratio (I), and enhancement ratio (E) were calculated. The relationships between the concentration of Aconitum alkaloids and μ of E. coli or S. aureus were discussed. The results showed that Aconitum alkaloids had little effect on E. coli and had a potentially inhibitory effect on the growth of S. aureus.

  20. Gastric and Duodenal Antiulcer Activity of Alkaloids: A Review

    Directory of Open Access Journals (Sweden)

    José Maria Barbosa-Filho

    2008-12-01

    Full Text Available Peptic ulcer disease is a deep gastrointestinal erosion disorder that involves the entire mucosal thickness and can even penetrate the muscular mucosa. Numerous natural products have been evaluated as therapeutics for the treatment of a variety of diseases, including this one. These products usually derive from plant and animal sources that contain active constituents such as alkaloids, flavonoids, terpenoids, tannins and others. The alkaloids are natural nitrogen-containing secondary metabolites mostly derived from amino acids and found in about 20% of plants. There has been considerable pharmacological research into the antiulcer activity of these compounds. In this work we review the literature on alkaloids with antiulcer activity, which covers about sixty-one alkaloids, fifty-five of which have activity against this disease when induced in animals.

  1. Structure, Biosynthesis, and Occurrence of Bacterial Pyrrolizidine Alkaloids

    DEFF Research Database (Denmark)

    Schimming, Olivia; Challinor, Victoria L; Tobias, Nicholas J;

    2015-01-01

    Pyrrolizidine alkaloids (PAs) are widespread plant natural products with potent toxicity and bioactivity. Herein, the identification of bacterial PAs from entomopathogenic bacteria using differential analysis by 2D NMR spectroscopy (DANS) and mass spectrometry is described. Their biosynthesis...

  2. NEW NORDITERPENOID ALKALOIDS FROM THE ROOTS OF ACONITUM GENICULATUM

    Institute of Scientific and Technical Information of China (English)

    ZHENG-BANG LI; LIANG XU; XI-XIAN JIAN; FENG-PENG WANG

    2001-01-01

    Four new norditerpenoid alkaloids, geniculatines A (1), B (4), C (7) and D (8), were isolated from the roots of Aconitum geniculatum Fletcher, and their structures were elucidated by spectral methods.

  3. A new pyrrole alkaloid from seeds of Castanea sativa.

    Science.gov (United States)

    Hiermann, Alois; Kedwani, Samir; Schramm, Hans Wolfgang; Seger, Christoph

    2002-02-01

    A new pyrrole alkaloid, methyl-(5-formyl-1H-pyrrole-2-yl)-4-hydroxybutyrate (1), was isolated from sweet chestnut seeds and its structure elucidated on the basis of data from NMR spectroscopy and by comparison with synthetic analogues.

  4. Activity of pyrrolizidine alkaloids against biofilm formation and Trichomonas vaginalis

    Science.gov (United States)

    Crotalaria genus belongs to the subfamily Papilionoideae comprising about 600 species spread throughout tropical, neotropical and subtropical regions. In this study, seeds of Crolatalaria pallida were used to the isolation of usaramine, a pyrrolizidine alkaloid. Thus, Pseudomonas aeruginosa and Stap...

  5. Monomeric banana lectin at acidic pH overrules conformational stability of its native dimeric form.

    Directory of Open Access Journals (Sweden)

    Javed M Khan

    Full Text Available Banana lectin (BL is a homodimeric protein categorized among jacalin-related family of lectins. The effect of acidic pH was examined on conformational stability of BL by using circular dichroism, intrinsic fluorescence, 1-anilino-8-napthalene sulfonate (ANS binding, size exclusion chromatography (SEC and dynamic light scattering (DLS. During acid denaturation of BL, the monomerization of native dimeric protein was found at pH 2.0. The elution profile from SEC showed two different peaks (59.65 ml & 87.98 ml at pH 2.0 while single peak (61.45 ml at pH 7.4. The hydrodynamic radii (R h of native BL was 2.9 nm while at pH 2.0 two species were found with R h of 1.7 and 3.7 nm. Furthermore at, pH 2.0 the secondary structures of BL remained unaltered while tertiary structure was significantly disrupted with the exposure of hydrophobic clusters confirming the existence of molten globule like state. The unfolding of BL with different subunit status was further evaluated by urea and temperature mediated denaturation to check their stability. As inferred from high Cm and ΔG values, the monomeric form of BL offers more resistance towards chemical denaturation than the native dimeric form. Besides, dimeric BL exhibited a Tm of 77°C while no loss in secondary structures was observed in monomers even up to 95°C. To the best of our knowledge, this is the first report on monomeric subunit of lectins showing more stability against denaturants than its native dimeric state.

  6. Conformational equilibria in monomeric alpha-synuclein at the single-molecule level.

    Directory of Open Access Journals (Sweden)

    Massimo Sandal

    2008-01-01

    Full Text Available Human alpha-Synuclein (alphaSyn is a natively unfolded protein whose aggregation into amyloid fibrils is involved in the pathology of Parkinson disease. A full comprehension of the structure and dynamics of early intermediates leading to the aggregated states is an unsolved problem of essential importance to researchers attempting to decipher the molecular mechanisms of alphaSyn aggregation and formation of fibrils. Traditional bulk techniques used so far to solve this problem point to a direct correlation between alphaSyn's unique conformational properties and its propensity to aggregate, but these techniques can only provide ensemble-averaged information for monomers and oligomers alike. They therefore cannot characterize the full complexity of the conformational equilibria that trigger the aggregation process. We applied atomic force microscopy-based single-molecule mechanical unfolding methodology to study the conformational equilibrium of human wild-type and mutant alphaSyn. The conformational heterogeneity of monomeric alphaSyn was characterized at the single-molecule level. Three main classes of conformations, including disordered and "beta-like" structures, were directly observed and quantified without any interference from oligomeric soluble forms. The relative abundance of the "beta-like" structures significantly increased in different conditions promoting the aggregation of alphaSyn: the presence of Cu2+, the pathogenic A30P mutation, and high ionic strength. This methodology can explore the full conformational space of a protein at the single-molecule level, detecting even poorly populated conformers and measuring their distribution in a variety of biologically important conditions. To the best of our knowledge, we present for the first time evidence of a conformational equilibrium that controls the population of a specific class of monomeric alphaSyn conformers, positively correlated with conditions known to promote the formation of

  7. Computational Studies on Cinchona Alkaloid-Catalyzed Asymmetric Organic Reactions.

    Science.gov (United States)

    Tanriver, Gamze; Dedeoglu, Burcu; Catak, Saron; Aviyente, Viktorya

    2016-06-21

    Remarkable progress in the area of asymmetric organocatalysis has been achieved in the last decades. Cinchona alkaloids and their derivatives have emerged as powerful organocatalysts owing to their reactivities leading to high enantioselectivities. The widespread usage of cinchona alkaloids has been attributed to their nontoxicity, ease of use, stability, cost effectiveness, recyclability, and practical utilization in industry. The presence of tunable functional groups enables cinchona alkaloids to catalyze a broad range of reactions. Excellent experimental studies have extensively contributed to this field, and highly selective reactions were catalyzed by cinchona alkaloids and their derivatives. Computational modeling has helped elucidate the mechanistic aspects of cinchona alkaloid catalyzed reactions as well as the origins of the selectivity they induce. These studies have complemented experimental work for the design of more efficient catalysts. This Account presents recent computational studies on cinchona alkaloid catalyzed organic reactions and the theoretical rationalizations behind their effectiveness and ability to induce selectivity. Valuable efforts to investigate the mechanisms of reactions catalyzed by cinchona alkaloids and the key aspects of the catalytic activity of cinchona alkaloids in reactions ranging from pharmaceutical to industrial applications are summarized. Quantum mechanics, particularly density functional theory (DFT), and molecular mechanics, including ONIOM, were used to rationalize experimental findings by providing mechanistic insights into reaction mechanisms. B3LYP with modest basis sets has been used in most of the studies; nonetheless, the energetics have been corrected with higher basis sets as well as functionals parametrized to include dispersion M05-2X, M06-2X, and M06-L and functionals with dispersion corrections. Since cinchona alkaloids catalyze reactions by forming complexes with substrates via hydrogen bonds and long

  8. A comparison of the antimalarial activity of the cinchona alkaloids against Plasmodium falciparum in vitro.

    Science.gov (United States)

    Wesche, D L; Black, J

    1990-06-01

    The effects of four major cinchona alkaloids: (-) quinine, (+) quinidine, (-)cinchonidine, and (+)cinchonine against Plasmodium falciparum FCQ-27/PNG were studied. The alkaloids were tested in vitro as either single alkaloids, racemic mixtures of stereoisomers, or as an equimolar combination of all four alkaloids. Results indicate (+)quinidine to be most effective and both (+)stereoisomers were more potent than the (-)stereoisomers. Inhibitory concentrations 50% (Ki) of racemic mixtures of stereoisomers were similar to those of the (+)stereoisomers alone. The Ki of four alkaloids in equimolar combination were similar to that of the (-) cinchonidine/(+)cinchonine racemic mixture. A total alkaloidal extract of Cinchona sp. was tested and compared with the pure alkaloids. HPLC analysis indicated that (+)cinchonine, (-)cinchonidine and (-)quinine were present in a ratio of approximately 1:1:2, respectively. The total alkaloid extract, with (-)stereoisomers predominating, was less effective than the four alkaloids in combination. The nature of the interaction between stereoisomers was investigated and appears to be one of addition.

  9. Aporphine alkaloids from Guatteria spp. with leishmanicidal activity.

    Science.gov (United States)

    Montenegro, Hector; Gutiérrez, Marcelino; Romero, Luz I; Ortega-Barría, Eduardo; Capson, Todd L; Rios, Luis Cubilla

    2003-07-01

    Fractionation of Guatteria amplifolia yielded the alkaloids xylopine (1), nornuciferine (4), lysicamine (6), and laudanosine (5). Fractionation of Guatteria dumetorum yielded the alkaloids cryptodorine (2) and nornantenine (3). Compounds 1-4 demonstrated significant activity against Leishmania mexicana and L. panamensis. Xylopine (1) was among the most active compounds (LD 50 = 3 microM) and showed a 37-fold higher toxicity towards L. mexicana than macrophages, the regular host cells of Leishmania spp.

  10. Identification and determination of ergot alkaloids in Morning Glory cultivars

    OpenAIRE

    Nowak, Julia; Woźniakiewicz, Michał; Klepacki, Piotr; Sowa, Anna; Kościelniak, Paweł

    2016-01-01

    Seeds of plants from Ipomoea genera contain numerous ergot alkaloids, including psychoactive ergine and ergometrine, and are often abused as so-called “legal highs.” In this work, an analytical method for determination of ergine and ergometrine, and identification of other alkaloids was developed, optimized, and validated. Three extraction techniques, ultrasound-assisted extraction in bath, or with sonotrode, and microwave-assisted extraction were evaluated, and it was concluded that ultrason...

  11. Evolution through time of Pyrrolizidine Alkaloids detection and quantification

    OpenAIRE

    Monteiro-Silva, Filipe; González-Aguilar, Gerardo

    2013-01-01

    Pyrrolizidine Alkaloids (PAs) are a group of naturally occurring alkaloids that are produced by plants as a defense mechanism against insect herbivores. The analytical methodologies employed for their detection have come a long way since the first analytical experiment and in the last 30 years had an enormous development, both technological and experimental. It is notorious that before the generalization of certain technologies, especially in a post-war atmosphere, most scientific researches ...

  12. Detection and quantification of pyrrolizidine alkaloids in antibacterial medical honeys.

    Science.gov (United States)

    Cramer, Luise; Beuerle, Till

    2012-12-01

    In recent years, there has been an increasing interest in antibacterial honey for wound care ranging from minor abrasions and burns to leg ulcers and surgical wounds. On the other hand, several recent studies demonstrated that honey for human consumption was contaminated with natural occurring, plant derived pyrrolizidine alkaloids.1,2-Unsaturated pyrrolizidine alkaloids are a group of secondary plant metabolites that show developmental, hepato-, and geno-toxicity as well as carcinogenic effects in animal models and in in vitro test systems. Hence, it was of particular interest to analyze the pyrrolizidine alkaloid content of medical honeys intended for wound care.19 different medical honey samples and/or batches were analyzed by applying a recently established pyrrolizidine alkaloid sum parameter method. 1,2-Unsaturated pyrrolizidine alkaloids were converted into the common necin backbone structures and were analyzed and quantified by GC-MS in the selected ion monitoring mode.All but one medical honey analyzed were pyrrolizidine alkaloid positive. The results ranged from 10.6 µg retronecine equivalents per kg to 494.5 µg retronecine equivalents/kg medical honey. The average pyrrolizidine alkaloid content of all positive samples was 83.6 µg retronecine equivalents/kg medical honey (average of all samples was 79.3 µg retronecine equivalents/kg medical honey). The limit of detection was 2.0 µg retronecine equivalents/kg medical honey, while the limit of quantification was 6.0 µg retronecine equivalents/kg medical honey (S/N > 7/1).Based on the data presented here and considering the fact that medical honeys can be applied to open wounds, it seems reasonable to discuss the monitoring of 1,2-unsaturated pyrrolizidine alkaloids in honey intended for wound treatment.

  13. Molecular genetics of alkaloid biosynthesis in Nicotiana tabacum.

    Science.gov (United States)

    Dewey, Ralph E; Xie, Jiahua

    2013-10-01

    Alkaloids represent an extensive group of nitrogen-containing secondary metabolites that are widely distributed throughout the plant kingdom. The pyridine alkaloids of tobacco (Nicotiana tabacum L.) have been the subject of particularly intensive investigation, driven largely due to the widespread use of tobacco products by society and the role that nicotine (16) (see Fig. 1) plays as the primary compound responsible for making the consumption of these products both pleasurable and addictive. In a typical commercial tobacco plant, nicotine (16) comprises about 90% of the total alkaloid pool, with the alkaloids nornicotine (17) (a demethylated derivative of nicotine), anatabine (15) and anabasine (5) making up most of the remainder. Advances in molecular biology have led to the characterization of the majority of the genes encoding the enzymes directly responsible the biosynthesis of nicotine (16) and nornicotine (17), while notable gaps remain within the anatabine (15) and anabasine (5) biosynthetic pathways. Several of the genes involved in the transcriptional regulation and transport of nicotine (16) have also been elucidated. Investigations of the molecular genetics of tobacco alkaloids have not only provided plant biologists with insights into the mechanisms underlying the synthesis and accumulation of this important class of plant alkaloids, they have also yielded tools and strategies for modifying the tobacco alkaloid composition in a manner that can result in changing the levels of nicotine (16) within the leaf, or reducing the levels of a potent carcinogenic tobacco-specific nitrosamine (TSNA). This review summarizes recent advances in our understanding of the molecular genetics of alkaloid biosynthesis in tobacco, and discusses the potential for applying information accrued from these studies toward efforts designed to help mitigate some of the negative health consequences associated with the use of tobacco products.

  14. Total synthesis of the bridged indole alkaloid apparicine.

    Science.gov (United States)

    Bennasar, M-Lluïsa; Zulaica, Ester; Solé, Daniel; Roca, Tomàs; García-Díaz, Davinia; Alonso, Sandra

    2009-11-06

    An indole-templated ring-closing metathesis or a 2-indolylacyl radical cyclization constitute the central steps of two alternative approaches developed to assemble the tricyclic ABC substructure of the indole alkaloid apparicine. From this key intermediate, an intramolecular vinyl halide Heck reaction accomplished the closure of the strained 1-azabicyclo[4.2.2]decane framework of the alkaloid with concomitant incorporation of the exocyclic alkylidene substituents.

  15. ISOLASI SENYAWA ALKALOID DARI DAUN SIDAGURI (Sida rhombifolia L.

    Directory of Open Access Journals (Sweden)

    Sovia Lenny

    2016-02-01

    Full Text Available The secondary metabolite compound was isolated from sidaguri (Sida rhombifolia L. leaves. The diethylether extract was subjected to a column chromatography with a mixture of chloroform:methanol (7:3 was obtained as amorf  (59 mg. The FT-IR and 1H-NMR spectrum indicated the isolated compound was alkaloid compound. Keywords : Sidaguri (Sida rhombifolia L., column chromatography, alkaloid

  16. Isolation of monomeric photosystem II that retains the subunit PsbS.

    Science.gov (United States)

    Haniewicz, Patrycja; De Sanctis, Daniele; Büchel, Claudia; Schröder, Wolfgang P; Loi, Maria Cecilia; Kieselbach, Thomas; Bochtler, Matthias; Piano, Dario

    2013-12-01

    Photosystem II has been purified from a transplastomic strain of Nicotiana tabacum according to two different protocols. Using the procedure described in Piano et al. (Photosynth Res 106:221-226, 2010) it was possible to isolate highly active PSII composed of monomers and dimers but depleted in their PsbS protein content. A "milder" procedure than the protocol reported by Fey et al. (Biochim Biophys Acta 1777:1501-1509, 2008) led to almost exclusively monomeric PSII complexes which in part still bind the PsbS protein. This finding might support a role for PSII monomers in higher plants.

  17. Monomeric CH3: A Small, Stable Antibody Domain with Therapeutic Promise | Poster

    Science.gov (United States)

    By Ashley DeVine, Staff Writer Antibody domains are emerging as promising biopharmaceuticals because of their relatively small size compared to full-sized antibodies, which are too large to effectively penetrate tumors and bind to sterically restricted therapeutic targets. In an article published in The Journal of Biological Chemistry, Tianlei Ying, Ph.D., Dimiter Dimitrov, Ph.D., and their colleagues in the Protein Interactions Group, Cancer and Inflammation Program, Center for Cancer Research, reported their design of a novel antibody domain, monomeric CH3 (mCH3).

  18. The Beckman DxI 800 prolactin assay demonstrates superior specificity for monomeric prolactin.

    LENUS (Irish Health Repository)

    Byrne, Brendan

    2010-02-01

    Commercially available prolactin immunoassays detect macroprolactin to variable degrees. Best practice requires laboratories to assess the cross-reactivity of their prolactin assay with macroprolactin, and where appropriate, introduce a screen for the presence of macroprolactin. Our policy has been to reanalyse hyperprolactinaemic samples following polyethylene glycol (PEG) precipitation and to report the resultant value as the monomeric prolactin content of the sample. The goal of this study was to determine the need to continue PEG precipitation when prolactin measurements with the Wallac AutoDELFIA were replaced by the Beckman DxI 800.

  19. Identification and determination of ergot alkaloids in Morning Glory cultivars.

    Science.gov (United States)

    Nowak, Julia; Woźniakiewicz, Michał; Klepacki, Piotr; Sowa, Anna; Kościelniak, Paweł

    2016-05-01

    Seeds of plants from Ipomoea genera contain numerous ergot alkaloids, including psychoactive ergine and ergometrine, and are often abused as so-called "legal highs." In this work, an analytical method for determination of ergine and ergometrine, and identification of other alkaloids was developed, optimized, and validated. Three extraction techniques, ultrasound-assisted extraction in bath, or with sonotrode, and microwave-assisted extraction were evaluated, and it was concluded that ultrasonic bath is the most suitable technique for extraction of ergot alkaloids. The extraction method was later optimized using a Doehlert experimental design with response surface methodology and used together with the optimized LC-Q-TOF-MS method. The analytical procedure was validated in terms of recovery and matrix effect, repeatability, and intermediate precision. Limits of detection and quantification were 1.0 and 3.0 ng mL(-1), respectively, and were sufficient for determination of ergot alkaloids in Ipomoea seeds. The analysis revealed that from five kinds of seeds purchased from different vendors, only three contained ergot alkaloids. Concentration of alkaloids and their relative abundance was similar in samples representative for whole seeds packs; however, when single seeds were analyzed, significant discrepancies in ergine and ergometrine concentrations were detected.

  20. Evaluation of Aconitum diterpenoid alkaloids as antiproliferative agents.

    Science.gov (United States)

    Wada, Koji; Ohkoshi, Emika; Zhao, Yu; Goto, Masuo; Morris-Natschke, Susan L; Lee, Kuo-Hsiung

    2015-04-01

    Little information has been reported on the antitumor effects of the diterpenoid alkaloid constituents of Aconitum plants, used in the herbal drug 'bushi'. This study was aimed at determining the antitumor activities of Aconitum C19-and C20-diterpenoid alkaloids and synthetic derivatives against lung (A549), prostate (DU145), nasopharyngeal (KB), and vincristine-resistant nasopharyngeal (KB-VIN) cancer cell lines. Newly synthesized C20-diterpenoid alkaloid derivatives showed substantial suppressive effects against all human tumor cell lines tested. In contrast, natural and derivatized C19-diterpenoid alkaloids showed only a slight or no effect. Most of the active compounds were hetisine-type C20-diterpenoid alkaloids, specifically kobusine and pseudokobusine analogs with two different substitution patterns, C-11 and C-11,15. Notably, several C20-diterpenoid alkaloids were more potent against multidrug-resistant KB subline KB-VIN cells. Pseudokobusine 11-3'-trifluoromethylbenzoate (94) is a possible promising new lead meriting additional evaluation against multidrug-resistant tumors.

  1. Analysis of Norditerpenoid Alkaloids Extracted from Aconitum sinomantanum Nakai by Electrospray Ionization Tandem Mass Spectrometry

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    Electrospray ionization mass spectrometry(ESI-MS) was applied simultaneously in determining norditerpenoid alkaloids from the roots of Aconitum sinomantanum Nakai (RAS) based on molecular mass information. The tandem mass spectra(ESI-MSn) provided the alkaloidal structural information, through which the existence of these alkaloids was further confirmed. Accordingly, six known norditerpenoid alkaloids were simultaneously determined on the basis of their ESI-MSn spectra. Furthermore, based on the diagnostic fragmentation pathways of alkaloidal MSn, a rapid method for direct detection and characterization of alkaloids from an ethanolic extract of RAS was described.

  2. Allosteric Partial Inhibition of Monomeric Proteases. Sulfated Coumarins Induce Regulation, not just Inhibition, of Thrombin

    Science.gov (United States)

    Verespy III, Stephen; Mehta, Akul Y.; Afosah, Daniel; Al-Horani, Rami A.; Desai, Umesh R.

    2016-01-01

    Allosteric partial inhibition of soluble, monomeric proteases can offer major regulatory advantages, but remains a concept on paper to date; although it has been routinely documented for receptors and oligomeric proteins. Thrombin, a key protease of the coagulation cascade, displays significant conformational plasticity, which presents an attractive opportunity to discover small molecule probes that induce sub-maximal allosteric inhibition. We synthesized a focused library of some 36 sulfated coumarins to discover two agents that display sub-maximal efficacy (~50%), high potency (150-fold). Michaelis-Menten, competitive inhibition, and site-directed mutagenesis studies identified exosite 2 as the site of binding for the most potent sulfated coumarin. Stern-Volmer quenching of active site-labeled fluorophore suggested that the allosteric regulators induce intermediate structural changes in the active site as compared to those that display ~80–100% efficacy. Antithrombin inactivation of thrombin was impaired in the presence of the sulfated coumarins suggesting that allosteric partial inhibition arises from catalytic dysfunction of the active site. Overall, sulfated coumarins represent first-in-class, sub-maximal inhibitors of thrombin. The probes establish the concept of allosteric partial inhibition of soluble, monomeric proteins. This concept may lead to a new class of anticoagulants that are completely devoid of bleeding. PMID:27053426

  3. Nortriptyline inhibits aggregation and neurotoxicity of alpha-synuclein by enhancing reconfiguration of the monomeric form.

    Science.gov (United States)

    Collier, Timothy J; Srivastava, Kinshuk R; Justman, Craig; Grammatopoulous, Tom; Hutter-Paier, Birgit; Prokesch, Manuela; Havas, Daniel; Rochet, Jean-Christophe; Liu, Fang; Jock, Kevin; de Oliveira, Patrícia; Stirtz, Georgia L; Dettmer, Ulf; Sortwell, Caryl E; Feany, Mel B; Lansbury, Peter; Lapidus, Lisa; Paumier, Katrina L

    2017-10-01

    The pathology of Parkinson's disease and other synucleinopathies is characterized by the formation of intracellular inclusions comprised primarily of misfolded, fibrillar α-synuclein (α-syn). One strategy to slow disease progression is to prevent the misfolding and aggregation of its native monomeric form. Here we present findings that support the contention that the tricyclic antidepressant compound nortriptyline (NOR) has disease-modifying potential for synucleinopathies. Findings from in vitro aggregation and kinetics assays support the view that NOR inhibits aggregation of α-syn by directly binding to the soluble, monomeric form, and by enhancing reconfiguration of the monomer, inhibits formation of toxic conformations of the protein. We go on to demonstrate that NOR inhibits the accumulation, aggregation and neurotoxicity of α-syn in multiple cell and animal models. These findings suggest that NOR, a compound with established safety and efficacy for treatment of depression, may slow progression of α-syn pathology by directly binding to soluble, native, α-syn, thereby inhibiting pathological aggregation and preserving its normal functions. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Monomeric, Oligomeric and Polymeric Proteins in Huntington Disease and Other Diseases of Polyglutamine Expansion

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    Guylaine Hoffner

    2014-03-01

    Full Text Available Huntington disease and other diseases of polyglutamine expansion are each caused by a different protein bearing an excessively long polyglutamine sequence and are associated with neuronal death. Although these diseases affect largely different brain regions, they all share a number of characteristics, and, therefore, are likely to possess a common mechanism. In all of the diseases, the causative protein is proteolyzed, becomes abnormally folded and accumulates in oligomers and larger aggregates. The aggregated and possibly the monomeric expanded polyglutamine are likely to play a critical role in the pathogenesis and there is increasing evidence that the secondary structure of the protein influences its toxicity. We describe here, with special attention to huntingtin, the mechanisms of polyglutamine aggregation and the modulation of aggregation by the sequences flanking the polyglutamine. We give a comprehensive picture of the characteristics of monomeric and aggregated polyglutamine, including morphology, composition, seeding ability, secondary structure, and toxicity. The structural heterogeneity of aggregated polyglutamine may explain why polyglutamine-containing aggregates could paradoxically be either toxic or neuroprotective.

  5. Synthesis and characterization of a monomeric mutant Cu/Zn superoxide dismutase with partially reconstituted enzymic activity.

    Science.gov (United States)

    Banci, L; Bertini, I; Chiu, C Y; Mullenbach, G T; Viezzoli, M S

    1995-12-15

    A monomeric analog of human Cu/Zn superoxide dismutase (F50E/G51E SOD), previously characterized and found to have reduced enzymic activity, was here further modified by replacing Glu133 with Gln. This substitution does not dramatically affect the coordination geometry at the active site, but enhances enzymic activity, and also increases the affinity for anions at the active site. This behavior parallels earlier published results in which this point mutation was made in the dimeric wild-type enzyme. The analog described here has afforded for the first time a monomeric superoxide dismutase with substantial activity. This point mutation does not significantly influence the protein structure but interactions with anions, including superoxide, are altered with respect to the monomeric form. The present monomeric Glu133Gln mutant has partially restored enzymic activity. The diminished activity of the monomeric analogs is discussed in the light of possible minor structural changes and some of their characteristics are compared with those of naturally occurring mutants associated with various neurological diseases.

  6. Effect of Alkaloid-Free and Alkaloid-Rich preparations from Uncaria tomentosa bark on mitotic activity and chromosome morphology evaluated by Allium Test.

    Science.gov (United States)

    Kuraś, Mieczysław; Pilarski, Radosław; Nowakowska, Julita; Zobel, Alicja; Brzost, Krzysztof; Antosiewicz, Justyna; Gulewicz, Krzysztof

    2009-01-12

    Uncaria tomentosa (Willd.) DC. is the most popular Peruvian plant, used in folk medicine for different purposes. It contains thousands of active compounds with great content of alkaloids. Two different fractions of Alkaloid-Rich and Alkaloid-Free were researched on chromosome morphology, mitotic activity and phases indexes. Cells of Allium Test (meristematic cells of root tips) were incubated up to 24h in different concentrations of Alkaloid-Free and Alkaloid-Rich fraction obtained from Uncaria tomentosa bark followed by 48 h of postincubation in water. The chromosome morphology was analyzed and the content of mitotic and phase indexes were done. Individual compounds, oxindole alkaloids, phenolic compounds and sugars were determined. In Alkaloid-Rich and Alkaloid-Free fractions (different in chemical composition) we observed condensation and contraction of chromosomes (more in Alkaloid-Rich) with retardation and/or inhibition of mitoses and changed mitotic phases. Postincubation reversed results in the highest concentration which was lethal (in mostly Alkaloid-Rich fraction). Our studies indicate that different action can depend on different groups of active compounds in a preparation either containing alkaloids or not. Other fraction analysis may be useful in the future.

  7. Alkaloids and athlete immune function: caffeine, theophylline, gingerol, ephedrine, and their congeners.

    Science.gov (United States)

    Senchina, David S; Hallam, Justus E; Kohut, Marian L; Nguyen, Norah A; Perera, M Ann d N

    2014-01-01

    Plant alkaloids are found in foods, beverages, and supplements consumed by athletes for daily nutrition, performance enhancement, and immune function improvement. This paper examined possible immunomodulatory roles of alkaloids in exercise contexts, with a focus on human studies. Four representative groups were scrutinized: (a) caffeine (guaranine, mateine); (b) theophylline and its isomers, theobromine and paraxanthine; (c) ginger alkaloids including gingerols and shogaol; and (d) ephedra alkaloids such as ephedrine and pseudoephedrine. Emerging or prospective alkaloid sources (Goji berry, Noni berry, and bloodroot) were also considered. Human in vitro and in vivo studies on alkaloids and immune function were often conflicting. Caffeine may be immunomodulatory in vivo depending on subject characteristics, exercise characteristics, and immune parameters measured. Caffeine may exhibit antioxidant capacities. Ginger may exert in vivo anti-inflammatory effects in certain populations, but it is unclear whether these effects are due to alkaloids or other biochemicals. Evidence for an immunomodulatory role of alkaloids in energy drinks, cocoa, or ephedra products in vivo is weak to nonexistent. For alkaloid sources derived from plants, variability in the reviewed studies may be due to the presence of unrecognized alkaloids or non-alkaloid compounds (which may themselves be immunomodulatory), and pre-experimental factors such as agricultural or manufacturing differences. Athletes should not look to alkaloids or alkaloid-rich sources as a means of improving immune function given their inconsistent activities, safety concerns, and lack of commercial regulation.

  8. Proapoptotic activity of Ukrain is based on Chelidonium majus L. alkaloids and mediated via a mitochondrial death pathway

    Directory of Open Access Journals (Sweden)

    Plasswilm Ludwig

    2006-01-01

    Full Text Available Abstract Background The anticancer drug Ukrain (NSC-631570 which has been specified by the manufacturer as semisynthetic derivative of the Chelidonium majus L. alkaloid chelidonine and the alkylans thiotepa was reported to exert selective cytotoxic effects on human tumour cell lines in vitro. Few clinical trials suggest beneficial effects in the treatment of human cancer. Aim of the present study was to elucidate the importance of apoptosis induction for the antineoplastic activity of Ukrain, to define the molecular mechanism of its cytotoxic effects and to identify its active constituents by mass spectrometry. Methods Apoptosis induction was analysed in a Jurkat T-lymphoma cell model by fluorescence microscopy (chromatin condensation and nuclear fragmentation, flow cytometry (cellular shrinkage, depolarisation of the mitochondrial membrane potential, caspase-activation and Western blot analysis (caspase-activation. Composition of Ukrain was analysed by mass spectrometry and LC-MS coupling. Results Ukrain turned out to be a potent inducer of apoptosis. Mechanistic analyses revealed that Ukrain induced depolarisation of the mitochondrial membrane potential and activation of caspases. Lack of caspase-8, expression of cFLIP-L and resistance to death receptor ligand-induced apoptosis failed to inhibit Ukrain-induced apoptosis while lack of FADD caused a delay but not abrogation of Ukrain-induced apoptosis pointing to a death receptor independent signalling pathway. In contrast, the broad spectrum caspase-inhibitor zVAD-fmk blocked Ukrain-induced cell death. Moreover, over-expression of Bcl-2 or Bcl-xL and expression of dominant negative caspase-9 partially reduced Ukrain-induced apoptosis pointing to Bcl-2 controlled mitochondrial signalling events. However, mass spectrometric analysis of Ukrain failed to detect the suggested trimeric chelidonine thiophosphortriamide or putative dimeric or monomeric chelidonine thiophosphortriamide intermediates

  9. Proapoptotic activity of Ukrain is based on Chelidonium majus L. alkaloids and mediated via a mitochondrial death pathway.

    Science.gov (United States)

    Habermehl, Daniel; Kammerer, Bernd; Handrick, René; Eldh, Therese; Gruber, Charlotte; Cordes, Nils; Daniel, Peter T; Plasswilm, Ludwig; Bamberg, Michael; Belka, Claus; Jendrossek, Verena

    2006-01-17

    The anticancer drug Ukrain (NSC-631570) which has been specified by the manufacturer as semisynthetic derivative of the Chelidonium majus L. alkaloid chelidonine and the alkylans thiotepa was reported to exert selective cytotoxic effects on human tumour cell lines in vitro. Few clinical trials suggest beneficial effects in the treatment of human cancer. Aim of the present study was to elucidate the importance of apoptosis induction for the antineoplastic activity of Ukrain, to define the molecular mechanism of its cytotoxic effects and to identify its active constituents by mass spectrometry. Apoptosis induction was analysed in a Jurkat T-lymphoma cell model by fluorescence microscopy (chromatin condensation and nuclear fragmentation), flow cytometry (cellular shrinkage, depolarisation of the mitochondrial membrane potential, caspase-activation) and Western blot analysis (caspase-activation). Composition of Ukrain was analysed by mass spectrometry and LC-MS coupling. Ukrain turned out to be a potent inducer of apoptosis. Mechanistic analyses revealed that Ukrain induced depolarisation of the mitochondrial membrane potential and activation of caspases. Lack of caspase-8, expression of cFLIP-L and resistance to death receptor ligand-induced apoptosis failed to inhibit Ukrain-induced apoptosis while lack of FADD caused a delay but not abrogation of Ukrain-induced apoptosis pointing to a death receptor independent signalling pathway. In contrast, the broad spectrum caspase-inhibitor zVAD-fmk blocked Ukrain-induced cell death. Moreover, over-expression of Bcl-2 or Bcl-xL and expression of dominant negative caspase-9 partially reduced Ukrain-induced apoptosis pointing to Bcl-2 controlled mitochondrial signalling events. However, mass spectrometric analysis of Ukrain failed to detect the suggested trimeric chelidonine thiophosphortriamide or putative dimeric or monomeric chelidonine thiophosphortriamide intermediates from chemical synthesis. Instead, the Chelidonium majus

  10. Properties and metathesis activity of monomeric and dimeric Mo centres variously located on γ-alumina A DFT study

    Science.gov (United States)

    Handzlik, Jarosław

    2007-05-01

    Ethene metathesis proceeding on monomeric and dimeric Mo species on the (1 0 0) and (1 1 0) γ-alumina is investigated by density functional theory, applying the cluster approach. The calculated vibrational frequencies of the surface OH groups are assigned to the experimental IR bands. It is shown that both monomeric and dimeric Mo forms can be the active sites of olefin metathesis. Metathesis activity and stability of the Mo-methylidene centres depend on their location on alumina. The differences in the sites reactivity are explained on the basis of their geometrical and electronic structure parameters. For the monomeric centres, isomerisation of the trigonal bipyramidal intermediate to the stable square pyramidal molybdacyclobutane is kinetically favoured over the cycloreversal step. The situation is opposite in the case of the dimeric species.

  11. Pyrrolizidine alkaloids in honey and bee pollen.

    Science.gov (United States)

    Dübecke, A; Beckh, G; Lüllmann, C

    2011-03-01

    A total of 3917 honey samples and 119 'bee pollen' samples (pollen collected by honeybees) were analysed for pyrrolizidine alkaloids (PAs). Some 0.05 M sulphuric acid was used for extraction followed by a clean-up step by means of solid-phase extraction. Separation and detection was achieved by target analysis using an LC-MS/MS system. PAs were found in 66% of the raw honeys (bulk honey not yet packaged in containers for sale in retail outlets) and in 94% of honeys available in supermarkets (retail honey). A total of 60% of the bee pollen samples were PA positive. The PA pattern was used to identify the potential origin of the PAs in honey, which was verified for the genus Echium by relative pollen analysis. The results give an estimate of the impact of PA-containing plants belonging to the genera Echium, Senecio and, to a certain extent, Eupatorium on PA levels in honey and can serve as a decision basis for beekeepers in order to find the most suitable location for the production of honey and bee pollen low in PAs.

  12. Dehydropyrrolizidine Alkaloid Toxicity, Cytotoxicity, and Carcinogenicity

    Directory of Open Access Journals (Sweden)

    Bryan L. Stegelmeier

    2016-11-01

    Full Text Available Dehydropyrrolizidine alkaloid (DHPA-producing plants have a worldwide distribution amongst flowering plants and commonly cause poisoning of livestock, wildlife, and humans. Previous work has produced considerable understanding of DHPA metabolism, toxicity, species susceptibility, conditions, and routes of exposure, and pathogenesis of acute poisoning. Intoxication is generally caused by contaminated grains, feed, flour, and breads that result in acute, high-dose, short-duration poisoning. Acute poisoning produces hepatic necrosis that is usually confirmed histologically, epidemiologically, and chemically. Less is known about chronic poisoning that may result when plant populations are sporadic, used as tisanes or herbal preparations, or when DHPAs contaminate milk, honey, pollen, or other animal-derived products. Such subclinical exposures may contribute to the development of chronic disease in humans or may be cumulative and probably slowly progress until liver failure. Recent work using rodent models suggest increased neoplastic incidence even with very low DHPA doses of short durations. These concerns have moved some governments to prohibit or limit human exposure to DHPAs. The purpose of this review is to summarize some recent DHPA research, including in vitro and in vivo DHPA toxicity and carcinogenicity reports, and the implications of these findings with respect to diagnosis and prognosis for human and animal health.

  13. Dehydropyrrolizidine Alkaloid Toxicity, Cytotoxicity, and Carcinogenicity

    Science.gov (United States)

    Stegelmeier, Bryan L.; Colegate, Steven M.; Brown, Ammon W.

    2016-01-01

    Dehydropyrrolizidine alkaloid (DHPA)-producing plants have a worldwide distribution amongst flowering plants and commonly cause poisoning of livestock, wildlife, and humans. Previous work has produced considerable understanding of DHPA metabolism, toxicity, species susceptibility, conditions, and routes of exposure, and pathogenesis of acute poisoning. Intoxication is generally caused by contaminated grains, feed, flour, and breads that result in acute, high-dose, short-duration poisoning. Acute poisoning produces hepatic necrosis that is usually confirmed histologically, epidemiologically, and chemically. Less is known about chronic poisoning that may result when plant populations are sporadic, used as tisanes or herbal preparations, or when DHPAs contaminate milk, honey, pollen, or other animal-derived products. Such subclinical exposures may contribute to the development of chronic disease in humans or may be cumulative and probably slowly progress until liver failure. Recent work using rodent models suggest increased neoplastic incidence even with very low DHPA doses of short durations. These concerns have moved some governments to prohibit or limit human exposure to DHPAs. The purpose of this review is to summarize some recent DHPA research, including in vitro and in vivo DHPA toxicity and carcinogenicity reports, and the implications of these findings with respect to diagnosis and prognosis for human and animal health. PMID:27916846

  14. Pyrrolizidine alkaloids from Heliotropium transoxanum Bunge

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    M. R. Delnavazi

    2016-02-01

    Full Text Available Background and objectives: The plants belonging to the genus Heliotropium L. (Boraginaceae are the main sources of toxic pyrrolizidine alkaloids (PAs. In the present study, we have investigated the PAs of the aerial parts of Heliotropium transoxanum Bunge, a perennial species native to Iran. Methods: Silica gel column chromatography and silica gel PTLC were applied for the isolation of PAs present in the total methanol extract of H. transoxanum. The structures of the isolated compounds were identified using 1H-NMR, 13C-NMR and EIMS spectral analyses. Results: Three PAs, heliotrine (1, lasiocarpine (2 and heliotrine N-oxide (3,with known mutagenic and genotoxic properties, were isolated from the aerial parts of H. transoxanum. Conclusion: The results of this study on the presence of toxic PAs in H. transoxanum introduce this herb as a poisonous species and also suggest it as an appropriate source for the isolation of heliotrine and lasiocarpine for further toxicological and pharmacological studies.

  15. Synthesis of Morphinan Alkaloids in Saccharomyces cerevisiae.

    Directory of Open Access Journals (Sweden)

    Elena Fossati

    Full Text Available Morphinan alkaloids are the most powerful narcotic analgesics currently used to treat moderate to severe and chronic pain. The feasibility of morphinan synthesis in recombinant Saccharomyces cerevisiae starting from the precursor (R,S-norlaudanosoline was investigated. Chiral analysis of the reticuline produced by the expression of opium poppy methyltransferases showed strict enantioselectivity for (S-reticuline starting from (R,S-norlaudanosoline. In addition, the P. somniferum enzymes salutaridine synthase (PsSAS, salutaridine reductase (PsSAR and salutaridinol acetyltransferase (PsSAT were functionally co-expressed in S. cerevisiae and optimization of the pH conditions allowed for productive spontaneous rearrangement of salutaridinol-7-O-acetate and synthesis of thebaine from (R-reticuline. Finally, we reconstituted a 7-gene pathway for the production of codeine and morphine from (R-reticuline. Yeast cell feeding assays using (R-reticuline, salutaridine or codeine as substrates showed that all enzymes were functionally co-expressed in yeast and that activity of salutaridine reductase and codeine-O-demethylase likely limit flux to morphine synthesis. The results of this study describe a significant advance for the synthesis of morphinans in S. cerevisiae and pave the way for their complete synthesis in recombinant microbes.

  16. Total synthesis of the indolizidine alkaloid tashiromine

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    McElhinney Alison D

    2008-01-01

    Full Text Available Abstract Background Tashiromine 1 is a naturally occurring indolizidine alkaloid. It has been the subject of thirteen successful total syntheses to date. Our own approach centres on the stereoselective construction of the indolizidine core by capture of an electrophilic acyliminium species by a pendant allylsilane. The key cyclisation precursor is constructed using olefin cross-metathesis chemistry, which has the potential to facilitate both racemic and asymmetric approaches, depending upon the choice of the allylsilane metathesis partner. Results The use of the allyltrimethylsilane cross-metathesis approach enables the rapid construction of the key cyclisation precursor 3 (3 steps from commercial materials, which undergoes acid-induced cyclisation to give the desired bicyclic indolizidine skeleton as a 96:4 mixture of diastereomers. Simple functional group interconversions allowed the completion of the total synthesis of racemic tashiromine in six steps (19% overall yield. Three chiral α-alkoxyallylsilanes (12,14 and 15 were prepared in enantioenriched form and their cross-metathesis reactions studied as part of a putative asymmetric approach to tashiromine. In the event, α-hydroxysilane 12 underwent isomerisation under the reaction conditions to acylsilane 17, while silanes 14 and 15 were unreactive towards metathesis. Conclusion A concise, stereoselective total synthesis of racemic tashiromine has been developed. Attempts to translate this into an asymmetric synthesis have thus far been unsuccessful.

  17. Alkaloids of the Annonaceae: occurrence and a compilation of their biological activities.

    Science.gov (United States)

    Lúcio, Ana Silvia Suassuna Carneiro; Almeida, Jackson Roberto Guedes da Silva; Da-Cunha, Emídio Vasconcelos Leitão; Tavares, Josean Fechine; Barbosa Filho, Jos Maria

    2015-01-01

    This chapter presents an overview of the chemistry and pharmacology of the alkaloids found in species of the Annonaceae family. The occurrence of alkaloids from Annonaceae species, as well as their chemical structures and pharmacological activities are summarized in informative and easy-to-understand tables. Within the Annonaceae family, the genera Annona, Duguetia, and Guatteria have led to many important publications. Valuable and comprehensive information about the structure of these alkaloids is provided. The alkaloids of the aporphine type represent the predominant group in this family. Many of the isolated alkaloids exhibit unique structures. In addition to the chemical structures, the pharmacological activities of some alkaloids are also presented in this chapter. Thus, the leishmanicidal, antimicrobial, antitumor, cytotoxic, and antimalarial activities observed for these alkaloids are highlighted. The chapter is presented as a contribution for the scientific community, mainly to enable the search for alkaloids in species belonging to the Annonaceae family.

  18. Biosynthesis, asymmetric synthesis, and pharmacology, including cellular targets, of the pyrrole-2-aminoimidazole marine alkaloids

    Digital Repository Service at National Institute of Oceanography (India)

    Al-Mourabit, A.; Zancanella, M.A.; Tilvi, S.; Romo, D.

    The pyrrole-2-aminoimidazole (P-2-AI) alkaloids are a growing family of marine alkaloids, now numbering well over 150 members, with high topographical and biological information content. Their intriguing structural complexity, rich and compact...

  19. Lyophilization-induced protein denaturation in phosphate buffer systems: monomeric and tetrameric beta-galactosidase.

    Science.gov (United States)

    Pikal-Cleland, K A; Carpenter, J F

    2001-09-01

    During freezing in phosphate buffers, selective precipitation of a less soluble buffer component and subsequent pH shifts may induce protein denaturation. Previous reports indicate significantly more inactivation and secondary structural perturbation of monomeric and tetrameric beta-galactosidase (beta-gal) during freeze-thawing in sodium phosphate (NaP) buffer as compared with potassium phosphate (KP) buffer. This observation was attributed to the significant pH shifts (from 7.0 to as low as 3.8) observed during freezing in the NaP buffer (1). In the current study, we investigated the impact of the additional stress of dehydration after freezing on the recovery of active protein on reconstitution and the retention of the native structure in the dried state. Freeze-drying monomeric and tetrameric beta-gal in either NaP or KP buffer resulted in significant secondary structural perturbations, which were greatest for the NaP samples. However, similar recoveries of active monomeric protein were observed after freeze-thawing and freeze-drying, indicating that most dehydration-induced unfolding was reversible on reconstitution of the freeze-dried protein. In contrast, the tetrameric protein was more susceptible to dehydration-induced denaturation as seen by the greater loss in activity after reconstitution of the freeze-dried samples relative to that measured after freeze-thawing. To ensure optimal protein stability during freeze-drying, the protein must be protected from both freezing and dehydration stresses. Although poly(ethylene glycol) and dextran are preferentially excluded solutes and should confer protection during freezing, they were unable to prevent lyophilization-induced denaturation. In addition, Tween did not foster maintenance of native protein during freeze-drying. However, sucrose, which hydrogen bonds to dried protein in the place of lost water, greatly reduced freezing- and drying-induced denaturation, as observed by the high retention of native

  20. Actions of piperidine alkaloid teratogens at fetal nicotinic acetylcholine receptors.

    Science.gov (United States)

    Green, Benedict T; Lee, Stephen T; Panter, Kip E; Welch, Kevin D; Cook, Daniel; Pfister, James A; Kem, William R

    2010-01-01

    Teratogenic alkaloids are found in many species of plants including Conium maculatum L., Nicotiana glauca, Nicotiana tabaccum, and multiple Lupinus spp. Fetal musculoskeletal defects produced by alkaloids from these plants include arthrogyropisis, scoliosis, torticollis, kyposis, lordosis, and cleft palate. A pharmacodynamic comparison of the alkaloids ammodendrine, anabasine, anabaseine, anagyrine, and coniine in SH-SY5Y cells and TE-671 cells was made. These alkaloids and their enantiomers were more effective in depolarizing TE-671 cells which express the human fetal-muscle type nicotinic acetylcholine receptor (nAChR) relative to SH-SY5Y cells which predominately express autonomic nAChRs. The rank order of potency in TE-671 cells was: anabaseine>(+)-anabasine>(-)-anabasine > (+/-)-anabasine>anagyrine>(-)-coniine > (+/-)-coniine>(+)-coniine>(+/-)-ammodendrine>(+)-ammodendrine. The rank order potency in SH-SY5Y cells was: anabaseine>(+)-anabasine>(-)-coniine>(+)-coniine>(+)-ammodendrine>anagyrine>(-)-anabasine>(+/-)-coniine>(+/-)-anabasine>(-)-ammodendrine. The actions of these alkaloids at nAChRs in both cell lines could be distinguished by their maximum effects in depolarizing cell membrane potential. The teratogenic action of these compounds may be related to their ability to activate and subsequently desensitize nAChRs.

  1. Micelle assisted structural conversion with fluorescence modulation of benzophenanthridine alkaloids

    Science.gov (United States)

    Pradhan, Ankur Bikash; Bhuiya, Sutanwi; Haque, Lucy; Tiwari, Richa; Das, Suman

    2017-01-01

    In this study we have reported the anionic surfactant (Sodium dodecyl sulfate, SDS) driven structural conversion of two benzophenanthridine plant alkaloids namely Chelerythrine (herein after CHL) and Sanguinarine (herein after SANG). Both the alkaloids exist in two forms: the charged iminium and the neutral alkanolamine form. The iminium form is stable at low pH ( 10.1). The fluorescence intensity of the alkanolamine form is much stronger than the iminium form. The iminium form of both the alkaloids remains stable whereas the alkanolamine form gets converted to the iminium form in the SDS micelle environment. The iminium form possesses positive charge and it seems that electrostatic interaction between the positively charged iminium and negatively charged surfactant leads to the stabilization of the iminium form in the Stern layer of the anionic micelle. Whereas the conversion of the alkanolamine form into the iminium form takes place and that can be monitored in naked eye since the iminium form is orange in colour and the alkanolamine form has blue violet emission. Such a detail insight about the photophysical properties of the benzophenanthridine alkaloids would be a valuable addition in the field of alkaloid-surfactant interaction.

  2. Pyrrolizidine alkaloids from seven wild-growing Senecio species in Serbia and Montenegro

    OpenAIRE

    2009-01-01

    The genus Senecio (family Asteraceae) is one of the largest in the world. It comprises about 1100 species which are the rich source of pyrrolizidine alkaloids. Plants containing pyrrolizidine alkaloids are among the most important sources of human and animal exposure to plant toxins and carcinogens. The pyrrolizidine alkaloids of seven Senecio species (S. erucifolius, S. othonnae, S. wagneri, S. subalpinus, S. carpathicus, S. paludosus and S. rupestris) were studied. Fourteen alkaloids were i...

  3. Extracellular monomeric tau protein is sufficient to initiate the spread of tau protein pathology.

    Science.gov (United States)

    Michel, Claire H; Kumar, Satish; Pinotsi, Dorothea; Tunnacliffe, Alan; St George-Hyslop, Peter; Mandelkow, Eckhard; Mandelkow, Eva-Maria; Kaminski, Clemens F; Kaminski Schierle, Gabriele S

    2014-01-10

    Understanding the formation and propagation of aggregates of the Alzheimer disease-associated Tau protein in vivo is vital for the development of therapeutics for this devastating disorder. Using our recently developed live-cell aggregation sensor in neuron-like cells, we demonstrate that different variants of exogenous monomeric Tau, namely full-length Tau (hTau40) and the Tau-derived construct K18 comprising the repeat domain, initially accumulate in endosomal compartments, where they form fibrillar seeds that subsequently induce the aggregation of endogenous Tau. Using superresolution imaging, we confirm that fibrils consisting of endogenous and exogenous Tau are released from cells and demonstrate their potential to spread Tau pathology. Our data indicate a greater pathological risk and potential toxicity than hitherto suspected for extracellular soluble Tau.

  4. Monomeric GLP-1/GIP/glucagon triagonism corrects obesity, hepatosteatosis, and dyslipidemia in female mice

    DEFF Research Database (Denmark)

    Jall, Sigrid; Sachs, Stephan; Clemmensen, Christoffer

    2017-01-01

    . RESULTS: Our results show that GLP-1/GIP/glucagon triple agonism inhibits food intake and decreases body weight and body fat mass with comparable potency in male and female mice that have been matched for body fat mass. Treatment improved dyslipidemia in both sexes and reversed diet......OBJECTIVE: Obesity is a major health threat that affects men and women equally. Despite this fact, weight-loss potential of pharmacotherapies is typically first evaluated in male mouse models of diet-induced obesity (DIO). To address this disparity we herein determined whether a monomeric peptide...... mice and a cohort of fatmass-matched C57BL/6J male mice were treated for 27 days via subcutaneous injections with either the GLP-1/GIP/glucagon triagonist or PBS. A second cohort of C57BL/6J male mice was included to match the females in the duration of the high-fat, high-sugar diet (HFD) exposure...

  5. Novel Monomeric Phenanthroline—Thallium(Ⅲ) Complexes Multinuclear NMR Characterization in Organic Solvents

    Institute of Scientific and Technical Information of China (English)

    GuiBinMA; JuliusGLASER

    2002-01-01

    A novel complex of monomeric thallium (Ⅲ) with the nitrogen donor ligand phenanthroline (phen) has been prepared and characterized by multimuclear NMR(1H,13C,205Tl). The three complexes exist in equilibria in DMSO and acetonitrile solution, which was proved by the 205Tl NMR spectra. The 1H and 13C NMR spectra of tris-phen T1(Ⅲ) complex have been measured, where the spin-spin coupling between T1(I=1/2) and 13C or 1H signals were observed with the 1H and 13C NMR spectroscopy in acetonitrile. The coupling constants are presented and the chemical shifts of complexes are discussed in detail.

  6. Novel Monomeric Phenanthroline - Thallium(Ⅲ) Complexes Multinuclear NMR Characterization in Organic Solvents

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A novel complex of monomeric thallium(III) with the nitrogen donor ligand phenanthrolinc (phen) has been prepared and characterized by multinuclear NMR (1H, 13C, 205T1).The three complexes exist in equilibria in DMSO and acetonitrile solution, which was proved by the 205Tl NMR spectra. The 1H and 13C NMR spectra of tris-phen Tl(III) complex have been measured, where the spin-spin coupling between TI (1 = 1/2) and 13C or 1H signals were observed with the 1H and 13C NMR spectroscopy in acetonitrile. The coupling constants are presented and the chemical shifts of complexes are discussed in detail.

  7. Alkaloids in the human food chain - Natural occurrence and possible adverse effects

    NARCIS (Netherlands)

    Koleva, I.; Beek, van T.A.; Soffers, A.E.M.F.; Dusemund, B.; Rietjens, I.

    2012-01-01

    Alkaloid-containing plants are an intrinsic part of the regular Western diet. The present paper summarizes the occurrence of alkaloids in the food chain, their mode of action and possible adverse effects including a safety assessment. Pyrrolizidine alkaloids are a reason for concern because of their

  8. HPTLC and GC/MS Study of Amaryllidaceae Alkaloids of Two Narcissus Species.

    Science.gov (United States)

    Shawky, Eman; Abou-Donia, Amina H; Darwish, Fikria A; Toaima, Soad M; Takla, Sarah S; Pigni, Natalia B; Bastida, Jaume

    2015-08-01

    In this article, we report on the alkaloid profile and dynamic of alkaloid content and diversity in two Narcissus plants at different stages of development. The alkaloid profile of the two Narcissus species was investigated by GC/MS and HPTLC. Fifty eight Amaryllidaceae alkaloids were detected, and 25 of them were identified in the different organs of N. tazetta and N. papyraceus. The alkaloid 3-O-methyl-9-O-demethylmaritidine is tentatively identified here for the first time from the Amaryllidaceae family, and four alkaloids (tazettamide, sternbergine, 1-O-acetyllycorine, 2,11-didehydro-2-dehydroxylycorine) are tentatively identified for the first time in the genus Narcissus. The different organs of the two species analyzed showed remarkable differences in their alkaloid pattern, type of biosynthesis, main alkaloid and number of alkaloids. Lycorine-type alkaloids dominated the alkaloid, metabolism in N. papyraceus, while alkaloids of narciclasine-, galanthamine- and homolycorine-types were found only in the species N. tazetta L.

  9. Steroidal glyco alkaloids and molluscicidal activity of Solanum asperum Rich. fruits

    Energy Technology Data Exchange (ETDEWEB)

    Silva, Tania M.S. [Instituto Multidisciplinar em Saude, Vitoria da Conquista, BA (Brazil). Campus Avancado Anisio Teixeira]. E-mail: sarmento@pesquisador.cnpq.br; Camara, Celso A. [Universidade Federal Rural de Pernambuco, Recife, PE (Brazil). Dept. de Quimica; Freire, Kristerson R.L.; Silva, Thiago G. da; Agra, Maria de F.; Bhattacharyya, Jnanabrata [Universidade Federal da Paraiba (UFPB), Joao Pessoa, PB (Brazil). Lab. de Tecnologia Farmaceutica

    2008-07-01

    Bioassay-guided fractionation of the alkaloidal extract of the green fruits of Solanum asperum afforded a new compound, solanandaine along with solasonine and solamargine. The total crude alkaloids as well as the isolated pure alkaloids exhibited significant molluscicidal activity. (author)

  10. Three new C20-diterpenoid alkaloids from Delphinium anthriscifolium var. savatieri

    Institute of Scientific and Technical Information of China (English)

    Xiao Yu Liu; Qiao Hong Chen; Feng Peng Wang

    2009-01-01

    Three new C20-diterpenoid alkaloids, designated as anthriscifolmines A-C (1-3), together with two known alkaloids denudatine and delgramine, were isolated from the whole herb of Delphinium anthriscifolium var. savatieri. The structures of these new alkaloids were elucidated on the basis of spectral data.

  11. Two new C19-diterpenoid alkaloids from roots Aconitum hemsleyanium var. atropurpureum

    Institute of Scientific and Technical Information of China (English)

    Pei Tang; Dong Lin Chen; Xi Xian Jian; Feng Peng Wang

    2007-01-01

    A new franchetine-type C19-diterpenoid alkaloid 3-hydroxyfranchetine 1 and a new aconitine-type C19-diterpenoid alkaloid atropurpursine 2 have been isolated from the roots of Aconitum hemsleyanium var.atropurpureum.The structures of these new alkaloids were established on the basis of spectral data.

  12. A Bisindole Alkaloid with Hedgehog Signal Inhibitory Activity from the Myxomycete Perichaena chrysosperma.

    Science.gov (United States)

    Shintani, Akinori; Toume, Kazufumi; Rifai, Yusnita; Arai, Midori A; Ishibashi, Masami

    2010-10-22

    6-Hydroxy-9'-methoxystaurosporinone (1), a new bisindole alkaloid, was isolated from field-collected fruiting bodies of the myxomycete Perichaena chrysosperma, together with two known compounds. The structure of the new alkaloid was elucidated from spectral data, and compound 1 was shown to have hedgehog signal inhibitory activity. A related new alkaloid, 6,9'-dihydroxystaurosporinone (4), was also isolated from Arcyria cinerea.

  13. Identification and quantification of isoquinoline alkaloids in the genus Sarcocapnos by GC-MS.

    Science.gov (United States)

    Suau, R; Cabezudo, B; Valpuesta, M; Posadas, N; Diaz, A; Torres, G

    2005-01-01

    Six cularine alkaloids, cularicine, O-methylcularicine, celtisine, cularidine, cularine and celtine, three isocularine alkaloids, sarcophylline, sarcocapnine and sarcocapnidine, and five non-cularine alkaloids, glaucine, protopine, ribasine, dihydrosanguinarine and chelidonine, were identified and quantified by GC-MS in nine taxa of the genus Sarcocapnos (Fumariaceae). The chemotaxonomic significance of the results is discussed.

  14. Kinetics of carbon monoxide binding to monomeric hemoproteins. Role of the proximal histidine.

    Science.gov (United States)

    Coletta, M; Ascenzi, P; Traylor, T G; Brunori, M

    1985-04-10

    The effect of pH on (i) the second-order rate constant for CO binding and (ii) the spectral properties of the deoxygenated derivative of several monomeric hemoproteins has been investigated in the pH range between 2.3 and 9.0. As in the case of 3-[1-imidazolyl]-propylamide monomethyl ester mesoheme, the rate constant for CO binding to sperm whale, horse, Dermochelys coriacea, Coryphaena hippurus, and Aplysia limacina myoglobins (the latter only in the presence of acetate/acetic acid mixture) increases, as the pH is lowered, to a value at least 1 order of magnitude higher than at pH 7.0. Such an effect is not observed in A. limacina myoglobin (in the absence of the acetate/acetic acid mixture) and Chironomus thummi thummi erythrocruorin. Moreover, the absorption spectrum, in the visible region, of the deoxy derivative of all these monomeric hemoproteins (with the exception of A. limacina myoglobin in the absence of the acetate/acetic acid mixture) undergoes a transition as the pH is lowered, an effect observed previously with 3-[1-imidazolyl]-propylamide monomethyl ester protoheme. On the basis of analogous spectroscopic and kinetic properties of chelated heme model compounds we attribute this behavior to the protonation of the N epsilon of the proximal imidazole involved in the bond with the iron atom. On the basis of this model the movement of the iron atom to the heme plane appears as a crucial step for CO binding, the activation free energy of the process amounting to approximately 2 kcal/mol.

  15. LRP1 Modulates APP Intraneuronal Transport and Processing in Its Monomeric and Dimeric State

    Directory of Open Access Journals (Sweden)

    Claus U. Pietrzik

    2017-04-01

    Full Text Available The low-density lipoprotein receptor-related protein 1, LRP1, interacts with APP and affects its processing. This is assumed to be mostly caused by the impact of LRP1 on APP endocytosis. More recently, also an interaction of APP and LRP1 early in the secretory pathway was reported whereat retention of LRP1 in the ER leads to decreased APP cell surface levels and in turn, to reduced Aβ secretion. Here, we extended the biochemical and immunocytochemical analyses by showing via live cell imaging analyses in primary neurons that LRP1 and APP are transported only partly in common (one third but to a higher degree in distinct fast axonal transport vesicles. Interestingly, co-expression of LRP1 and APP caused a change of APP transport velocities, indicating that LRP1 recruits APP to a specific type of fast axonal transport vesicles. In contrast lowered levels of LRP1 facilitated APP transport. We further show that monomeric and dimeric APP exhibit similar transport characteristics and that both are affected by LRP1 in a similar way, by slowing down APP anterograde transport and increasing its endocytosis rate. In line with this, a knockout of LRP1 in CHO cells and in primary neurons caused an increase of monomeric and dimeric APP surface localization and in turn accelerated shedding by meprin β and ADAM10. Notably, a choroid plexus specific LRP1 knockout caused a much higher secretion of sAPP dimers into the cerebrospinal fluid compared to sAPP monomers. Together, our data show that LRP1 functions as a sorting receptor for APP, regulating its cell surface localization and thereby its processing by ADAM10 and meprin β, with the latter exhibiting a preference for APP in its dimeric state.

  16. LRP1 Modulates APP Intraneuronal Transport and Processing in Its Monomeric and Dimeric State.

    Science.gov (United States)

    Herr, Uta-Mareike; Strecker, Paul; Storck, Steffen E; Thomas, Carolin; Rabiej, Verena; Junker, Anne; Schilling, Sandra; Schmidt, Nadine; Dowds, C Marie; Eggert, Simone; Pietrzik, Claus U; Kins, Stefan

    2017-01-01

    The low-density lipoprotein receptor-related protein 1, LRP1, interacts with APP and affects its processing. This is assumed to be mostly caused by the impact of LRP1 on APP endocytosis. More recently, also an interaction of APP and LRP1 early in the secretory pathway was reported whereat retention of LRP1 in the ER leads to decreased APP cell surface levels and in turn, to reduced Aβ secretion. Here, we extended the biochemical and immunocytochemical analyses by showing via live cell imaging analyses in primary neurons that LRP1 and APP are transported only partly in common (one third) but to a higher degree in distinct fast axonal transport vesicles. Interestingly, co-expression of LRP1 and APP caused a change of APP transport velocities, indicating that LRP1 recruits APP to a specific type of fast axonal transport vesicles. In contrast lowered levels of LRP1 facilitated APP transport. We further show that monomeric and dimeric APP exhibit similar transport characteristics and that both are affected by LRP1 in a similar way, by slowing down APP anterograde transport and increasing its endocytosis rate. In line with this, a knockout of LRP1 in CHO cells and in primary neurons caused an increase of monomeric and dimeric APP surface localization and in turn accelerated shedding by meprin β and ADAM10. Notably, a choroid plexus specific LRP1 knockout caused a much higher secretion of sAPP dimers into the cerebrospinal fluid compared to sAPP monomers. Together, our data show that LRP1 functions as a sorting receptor for APP, regulating its cell surface localization and thereby its processing by ADAM10 and meprin β, with the latter exhibiting a preference for APP in its dimeric state.

  17. Pyrrolizidine alkaloid-derived DNA adducts as a common biological biomarker of pyrrolizidine alkaloid-induced tumorigenicity.

    Science.gov (United States)

    Xia, Qingsu; Zhao, Yuewei; Von Tungeln, Linda S; Doerge, Daniel R; Lin, Ge; Cai, Lining; Fu, Peter P

    2013-09-16

    Pyrrolizidine alkaloid-containing plants are the most common poisonous plants affecting livestock, wildlife, and humans. The U.S. National Toxicology Program (NTP) classified riddelliine, a tumorigenic pyrrolizidine alkaloid, as "reasonably anticipated to be a human carcinogen" in the NTP 12th Report on Carcinogens in 2011. We previously determined that four DNA adducts were formed in rats dosed with riddelliine. The structures of the four DNA adducts were elucidated as (i) a pair of epimers of 7-hydroxy-9-(deoxyguanosin-N(2)-yl)dehydrosupinidine adducts (termed as DHP-dG-3 and DHP-dG-4) as the predominant adducts; and (ii) a pair of epimers of 7-hydroxy-9-(deoxyadenosin-N(6)-yl)dehydrosupinidine adducts (termed as DHP-dA-3 and DHP-dA-4 adducts). In this study, we selected a nontumorigenic pyrrolizidine alkaloid, platyphylliine, a pyrrolizidine alkaloid N-oxide, riddelliine N-oxide, and nine tumorigenic pyrrolizidine alkaloids (riddelliine, retrorsine, monocrotaline, lycopsamine, retronecine, lasiocarpine, heliotrine, clivorine, and senkirkine) for study in animals. Seven of the nine tumorigenic pyrrolizidine alkaloids, with the exception of lycopsamine and retronecine, are liver carcinogens. At 8-10 weeks of age, female F344 rats were orally gavaged for 3 consecutive days with 4.5 and 24 μmol/kg body weight test article in 0.5 mL of 10% DMSO in water. Twenty-four hours after the last dose, the rats were sacrificed, livers were removed, and liver DNA was isolated for DNA adduct analysis. DHP-dG-3, DHP-dG-4, DHP-dA-3, and DHP-dA-4 adducts were formed in the liver of rats treated with the individual seven hepatocarcinogenic pyrrolizidine alkaloids and riddelliine N-oxide. These DNA adducts were not formed in the liver of rats administered retronecine, the nontumorigenic pyrrolizidine alkaloid, platyphylliine, or vehicle control. These results indicate that this set of DNA adducts, DHP-dG-3, DHP-dG-4, DHP-dA-3, and DHP-dA-4, is a common biological biomarker of

  18. Activity of Alkaloids on Peptic Ulcer: What’s New?

    Directory of Open Access Journals (Sweden)

    Raphaela Francelino do Nascimento

    2015-01-01

    Full Text Available Peptic ulcer is a common disease characterized by lesions that affect the mucosa of the esophagus, stomach and/or duodenum, and may extend into the muscular layer of the mucosa. Natural products have played an important role in the process of development and discovery of new drugs, due to their wide structural diversity and present, mostly specific and selective biological activities. Among natural products the alkaloids, biologically active secondary metabolites, that can be found in plants, animals or microorganisms stand out. The alkaloids are compounds consisting of a basic nitrogen atom that may or may not be part of a heterocyclic ring. This review will describe 15 alkaloids with antiulcer activity in animal models and in vitro studies.

  19. [Concentration and determination of strychnine alkaloid in biological fluids].

    Science.gov (United States)

    Zhang, Jing; He, Lang-chong; Fu, Qiang

    2005-02-01

    To establish a new method for determination of strychnine alkaloid in biological fluids based on molecularly imprinted polymers. A strychnine molecularly imprinted monolithic column was prepared by in-situ molecularly imprinted technique. The polymer was filled to a 1cm column, and a method was developed to concentrate and determine strychnine alkaloids in biological fluids. the limit of detection of the method was 4.9 ng, and the recoveries were more than 92%. The relative standard deviations were smaller than 6.59%. The linear correlation coefficients of standard curves were 0.999 1 and 0.9966 respectively. This method was applied to concentrate and determine strychnine in plasma and urine of poisoned rabbit. The new method could concentrate and simultaneously determine strychnine alkaloids in biological fluids, and it was applied to forensic toxicological analysis.

  20. Synthesis of bicyclic alkaloids from the iridoid antirrhinoside

    DEFF Research Database (Denmark)

    Frederiksen, Signe Maria

    The present thesis describes the isolation of the iridoid glucoside antirrhinoside from Antirrhinum majus, and the approaches made towards its transformation into analogues of biologically active compounds, with special interest in syntheses of bicyclic alkaloids.A synthetic piperidine monoterpene...... alkaloid was prepared from antirrhinoside by means of an enzymatic cleavage to afford the aglucone, followed by a double reductive amination with benzylamine hydrochloride and sodium cyanoborohydride. The resulting piperidine was modified by opening of the epoxide on the cyclopropane ring by azide...... strategy was therefore abandoned.A one-pot reaction involving ozonolysis and subsequent reduction of the 5,6-O-isopropylidene-2',3',4',6'-tetra-O-acetyl antirrhinoside yielded a diol, which was considered a potential intermediate in the preparation of enantiopure 3-azabicyclo[3.3.0]octane alkaloids...

  1. Nonaqueous CE ESI-IT-MS analysis of Amaryllidaceae alkaloids.

    Science.gov (United States)

    Zhang, Yulin; Chen, Zilin

    2013-03-01

    The Amaryllidaceae are widely distributed medical plants. Lycorine, lycoramine, lycoremine, and lycobetaine are the major active alkaloids in Amaryllidaceae plants. A nonaqueous CE ESI-IT-MS method for separation, identification, and quantification of the Amaryllidaceae alkaloids has been developed. The MS(1-3) behavior has been studied and the fragmentation pathways of main fragment ions have been proposed. The effects of several factors such as composition and concentration of buffer, applied voltage, composition, and flow rate of the sheath liquid, nebulizing gas pressure, flow rate, and temperature of drying gas were investigated. Under the optimal conditions, the linear concentration range of these compounds was wide with the correlation coefficient (R(2) ) >0.99. RSDs of migration time and peak areas were alkaloids in the Lycoris radiata roots.

  2. Terpenoid Indole Alkaloids Biosynthesis and Metabolic Engineering in Catharanthus roseus

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Catharanthus roseus L. (Madagascar periwinkle) biosynthesizes a diverse array of secondary metabolites including anticancer dimeric alkaloids (vinblastine and vincristine) and antihypertensive alkaloids (ajmalicine and serpentine). The multi-step terpenoid indole alkaloids (TIAs) biosynthetic pathway in C. roseus is complex and is under strict molecular regulation. Many enzymes and genes involved in the TIAs biosynthesis have been studied in recent decades. Moreover,some regulatory proteins were found recently to control the production of TIAs in C. roseus. Based on mastering the rough scheme of the pathway and cloning the related genes, metabolic engineering of TIAs biosynthesis has been studied in C.roseus aiming at increasing the desired secondary metabolites in the past few years. The present article summarizes recent advances in isolation and characterization of TIAs biosynthesis genes and transcriptional regulators involved in the second metabolic control in C. roseus. Metabolic engineering applications in TIAs pathway via overexpression of these genes and regulators in C. roseus are also discussed.

  3. In vitro production of alkaloids: Factors, approaches, challenges and prospects

    Directory of Open Access Journals (Sweden)

    Sayeed Ahmad

    2013-01-01

    Full Text Available The wide diversity of plant secondary metabolites is largely used for the production of various pharmaceutical compounds. In vitro cell tissue or organ culture has been employed as a possible alternative to produce such industrial compounds. Tissue culture techniques provide continuous, reliable, and renewable source of valuable plant pharmaceuticals and might be used for the large-scale culture of the plant cells from which these secondary metabolites can be extracted. Alkaloids are one of the most important secondary metabolites known to play a vital role in various pharmaceutical applications leading to an increased commercial importance in recent years. The tissue culture techniques may be utilized to improve their production of alkaloids via somaclonal variations and genetic transformations. The focus of this review is toward the application of different tissue culture methods/techniques employed for the in vitro production of alkaloids with a systematic approach to improve their production.

  4. THE ALKALOID CYTISINE IN THE CELL CULTURE

    Directory of Open Access Journals (Sweden)

    Gazaliev A.M.

    2012-08-01

    Full Text Available Alkaloids are vegetative establishments of complex and original structure with nitrous heterocycles in the basis. For a long time they drew researchers’ attention because of their unique and specific physiological effect on alive organisms. Not all the representatives of the globe’s flora contain these unique substances. Alkaloid cytisine is to be found mainly in the plants of the fabaceous family - Fabaceae. For the cytisine production the seeds of Thermopsis lanceolata R.Br (T. lanceolata R.Br and Cytisus laburnum (C. laburnum are used as a raw material. The object of the research is T. lanceolata cell culture. Sterile sprouts are used at the first stage of the experiment. Callus genesis is accompanied with dedifferentiation. It leads to the cellular organization simplification. Based on an important property of a plant cell, such as totipotency, there appears the formation of the “de novo” biosynthetic device. The cultivation algorithm consists of two basic stages: (i the cultivation conditions optimization of callus with a high level of the primary metabolites biosynthesis (Aspartat – lysine; (ii the research of cultivation chemical and physical factors influence on the secondary metabolite (cytisine biosynthesis and accumulation. During the cultivation the Murashige and Skoog classical recipe of nutrient medium will be used. Optimization of the cultivation conditions will concern the phytohormones, macro- and micronutrients content, as the purpose of optimization is the production of the determined high-level competence embriogenical callus. The main problem is genetic heterogeneity of a cellular population and instability of morpho-physiological processes. The correct management of higher plants cells population is possible at the synchronization of a cellular cycle phases. The references analysis has shown that it is almost impossible to synchronize cellular cycles in the culture of plant tissue. The application of chemical

  5. Hydrofocusing Bioreactor Produces Anti-Cancer Alkaloids

    Science.gov (United States)

    Gonda, Steve R.; Valluri, Jagan V.

    2011-01-01

    microgravitation of an HFB do not need to maintain the same surface forces as in normal Earth gravitation, they can divert more energy sources to growth and differentiation and, perhaps, to biosynthesis of greater quantities of desired medicinal compounds. Because one can adjust the HFB to vary effective gravitation, one can also test the effects of intermediate levels of gravitation on biosynthesis of various products. The potential utility of this methodology for producing drugs was demonstrated in experiments in which sandalwood and Madagascar periwinkle cells were grown in an HFB. The conditions in the HFB were chosen to induce the cells to form into aggregate cultures that produced anti-cancer indole alkaloids in amounts greater than do comparable numbers of cells of the same species cultured according to previously known methodologies. The observations made in these experiments were interpreted as suggesting that the aggregation of the cells might be responsible for the enhancement of production of alkaloids.

  6. Minor alkaloids from Guatteria dumetorum with antileishmanial activity.

    Science.gov (United States)

    Correa, Jhonny Edmith; Ríos, Carlos Hernán; del Rosario Castillo, Amparo; Romero, Luz I; Ortega-Barría, Eduardo; Coley, Phyllis D; Kursar, Thomas A; Heller, Maria Verónica; Gerwick, William H; Rios, Luis Cubilla

    2006-02-01

    Nine known alkaloids [(+)-isodomesticine (1), (+)-norisodomesticine (2), (+)-nantenine ( 3), (+)-neolitsine (4), (+)-lirioferine (5), (+)-N-methyllaurotetanine (6), (+)-norlirioferine (7), (+)-isoboldine (8) and (+)-reticuline (9)] were isolated from young leaves of Guatteria dumetorum. Their structures were confirmed by NMR, mass and UV spectral analysis and by comparison to literature data. The growth inhibitory activity of each alkaloid was determined against the parasite Leishmania mexicana. Compounds 1-4 all showed significant activity whereby potency increased when a methylenedioxy functionality was present, especially at the 1,2-positions.

  7. Molluscicidal acridone alkaloids from Angostura paniculata: isolation, structures, and synthesis.

    Science.gov (United States)

    Vieira, P C; Kubo, I; Kujime, H; Yamagiwa, Y; Kamikawa, T

    1992-08-01

    Two novel acridone alkaloids, cuspanine [1] and cusculine [2], were isolated from the CH2Cl2 extract of the leaves of Angostura paniculata (Rutaceae). Their structures were established as 1-hydroxy-2,3,5,6-tetramethoxy-9-acridone for 1 and 1,2,3,5,6-pentamethoxy-9-acridone for 2 by means of spectroscopic studies, in particular nmr. These structural assignments were confirmed by synthesis, using a direct metallation method as a key reaction. Both alkaloids exhibited moderate molluscicidal activity against an aquatic snail, Biomphalaria glabrata, and cytotoxicity against several types of carcinoma cell lines.

  8. Cat's claw oxindole alkaloid isomerization induced by common extraction methods

    Directory of Open Access Journals (Sweden)

    Samuel Kaiser

    2013-01-01

    Full Text Available Cat's claw oxindole alkaloids are prone to isomerization in aqueous solution. However, studies on their behavior in extraction processes are scarce. This paper addressed the issue by considering five commonly used extraction processes. Unlike dynamic maceration (DM and ultrasound-assisted extraction, substantial isomerization was induced by static maceration, turbo-extraction and reflux extraction. After heating under reflux in DM, the kinetic order of isomerization was established and equations were fitted successfully using a four-parameter Weibull model (R² > 0.999. Different isomerization rates and equilibrium constants were verified, revealing a possible matrix effect on alkaloid isomerization.

  9. Quinolizidines alkaloids: Petrosin and xestospongins from the sponge Oceanapia sp.

    Indian Academy of Sciences (India)

    Keisham Sarjit Singh; Babulal Das; Chandrakant G Naik

    2011-09-01

    A bisquinolizidine alkaloid, petrosin (1) and a series of bis-1-oxaquinolizidine, xestospongins (2-9), were obtained from the ethyl acetate extract of the sponge Oceanapia sp. Petrosin was obtained along with xestospongin- C, D, E, F, G, H, I and J having di-hetroatom rings, from the ethyl acetate extract of the sponge. The compounds exhibited moderate to high activities against some microorganisms and clinical isolates. The structures of the alkaloids were elucidated by NMR and ESIMS spectroscopic data. The structure of petrosin was confirmed by an X-ray diffraction study.

  10. Recent Advances in the Synthesis of Morphine and Related Alkaloids

    Science.gov (United States)

    Chida, Noritaka

    Morphine, an alkaloid isolated from the opium poppy, has been widely used as an analgesic, and has been a fascinating synthetic target of organic chemists. After the first total synthesis reported in 1952, a number of synthetic studies toward morphine have been reported, and findings obtained in such studies have greatly contributed to the progress of synthetic organic chemistry as well as medicinal chemistry. This review provides an overview of recent studies toward the total synthesis of morphine and related alkaloids. Work reported in the literature since 2004 will be reviewed.

  11. New cyclopeptide alkaloid and lignan glycoside from Justicia procumbens.

    Science.gov (United States)

    Jin, Hong; Chen, Li; Tian, Ying; Li, Bin; Dong, Jun-Xing

    2015-01-01

    This study reported a new cyclopeptide alkaloid, justicianene A (1), and a new lignan glycoside, procumbenoside H (2), isolated from Justicia procumbens. The structures of the new compounds were elucidated by means of spectroscopic analysis, including extensive 2D NMR studies and mass spectrometry. Cyclopeptide alkaloids were first observed from the genus Justicia. Compound 2 was cytotoxic against human LoVo colon carcinoma cells with an IC50 value of 17.908 ± 1.949 μM.

  12. Anxiolytic effects of erythrinian alkaloids from Erythrina mulungu.

    Science.gov (United States)

    Flausino, Otavio; Santos, Luciana de Avila; Verli, Hugo; Pereira, Ana Maria; Bolzani, Vanderlan da Silva; Nunes-de-Souza, Ricardo Luiz

    2007-01-01

    One new erythrinian alkaloid derivative, (+)-11alpha-hydroxyerythravine (1), and the known (+)-erythravine (2) and (+)-alpha-hydroxyerysotrine (3) were isolated from the flowers of Erythrina mulungu. Their structures were determined by spectroscopic/spectrometric data interpretation of 1H, 13C, and 2D NMR and MS experiments. The relative configuration was established by NOESY analysis, while the conformation adopted by these molecules was evaluated through molecular modeling studies and coupling constants obtained by NMR analysis. Furthermore, the anxiolytic effects of the E. mulungu aqueous alcoholic crude extract and of the purified alkaloids were evaluated using the elevated T-maze test.

  13. Binding of tropane alkaloids to nicotinic and muscarinic acetylcholine receptors.

    Science.gov (United States)

    Schmeller, T; Sporer, F; Sauerwein, M; Wink, M

    1995-07-01

    Fourteen tropane and related alkaloids were analyzed for their affinity for nicotinic and/or muscarinic acetylcholine receptors. The biogenetic intermediates littorine, 6 beta-hydroxyhyoscyamine, 7 beta-hydroxyhyoscyamine exhibit similar affinities at the muscarinic receptor as scopolamine and atropine. The quarternary derivatives N-methylatropine and N-methylscopolamine show the highest binding with IC50 values of less than 100 pM and 300 pM, respectively. The tropane alkaloids (including cocaine) also bind to the nicotinic acetylcholine receptor, albeit with much lower affinities.

  14. Taichunamides: Prenylated Indole Alkaloids from Aspergillus taichungensis (IBT 19404)

    DEFF Research Database (Denmark)

    Kagiyama, Ippei; Kato, Hikaru; Nehira, Tatsuo

    2016-01-01

    Seven new prenylated indole alkaloids, taichunamides A–G, were isolated from the fungus Aspergillus taichungensis (IBT 19404). Taichunamides A and B contained an azetidine and 4‐pyridone units, respectively, and are likely biosynthesized from notoamide S via (+)‐6‐epi‐stephacidin A. Taichunamides C...... and D contain endoperoxide and methylsulfonyl units, respectively. This fungus produced indole alkaloids containing an anti‐bicyclo[2.2.2]diazaoctane core, whereas A. protuberus and A. amoenus produced congeners with a syn‐bicyclo[2.2.2]diazaoctane core. Plausible biosynthetic pathways to access...

  15. Effect of processing on the alkaloids in Aconitum tubers by HPLC-TOF/MS

    Directory of Open Access Journals (Sweden)

    Min Liu

    2017-06-01

    Full Text Available According to the Chinese Pharmacopoeia 2015, only processed Aconitum tubers can be clinically applied, and the effect of processing is unclear. This research aimed to explore the effect of processing on cardiac efficacy of alkaloids in Aconitum tubers. First, the chemical ingredients in unprocessed and processed Aconitum tubers were identified and compared by using high performance liquid chromatography time-of-flight mass spectrometry (HPLC-TOF/MS and multivariate pattern recognition methods. Then the representative alkaloids in Aconitum tubers, aconitine, benzoylaconine, and aconine, which belong to diester-diterpenoid alkaloids, monoester-diterpenoid alkaloids, and amine-diterpenoid alkaloids, respectively, were selected for further validation of attenuated mechanism. Subsequent pharmacological experiments with aconitine, benzoylaconine, and aconine in SD rats were used for validate the effect of processing on cardiac functions. After processing the Aconitum tubers, it was found that the contents of diester-diterpenoid alkaloids were reduced, and those of monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids were increased, suggesting that diester-diterpenoid alkaloids were transformed into monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids. Through further decocting the aconitine in boiling water, it was confirmed that the three alkaloids could be progressively transformed. Pharmacological experiments with aconitine, benzoylaconine, and aconine in SD rats showed that aconitine at a dose of 0.01 mg/kg and aconine at a dose of 10 mg/kg enhanced the cardiac function, while benzoylaconine at a dose of 2 mg/kg weakened the cardiac function. The effect of processing is attributed to the transformation of the most toxic diester-diterpenoid alkaloids into less toxic monoester-diterpenoid alkaloids and amine-diterpenoid alkaloids.

  16. Quantification of the predominant monomeric catechins in baking chocolate standard reference material by LC/APCI-MS.

    Science.gov (United States)

    Nelson, Bryant C; Sharpless, Katherine E

    2003-01-29

    Catechins are polyphenolic plant compounds (flavonoids) that may offer significant health benefits to humans. These benefits stem largely from their anticarcinogenic, antioxidant, and antimutagenic properties. Recent epidemiological studies suggest that the consumption of flavonoid-containing foods is associated with reduced risk of cardiovascular disease. Chocolate is a natural cocoa bean-based product that reportedly contains high levels of monomeric, oligomeric, and polymeric catechins. We have applied solid-liquid extraction and liquid chromatography coupled with atmospheric pressure chemical ionization-mass spectrometry to the identification and determination of the predominant monomeric catechins, (+)-catechin and (-)-epicatechin, in a baking chocolate Standard Reference Material (NIST Standard Reference Material 2384). (+)-Catechin and (-)-epicatechin are detected and quantified in chocolate extracts on the basis of selected-ion monitoring of their protonated [M + H](+) molecular ions. Tryptophan methyl ester is used as an internal standard. The developed method has the capacity to accurately quantify as little as 0.1 microg/mL (0.01 mg of catechin/g of chocolate) of either catechin in chocolate extracts, and the method has additionally been used to certify (+)-catechin and (-)-epicatechin levels in the baking chocolate Standard Reference Material. This is the first reported use of liquid chromatography/mass spectrometry for the quantitative determination of monomeric catechins in chocolate and the only report certifying monomeric catechin levels in a food-based Standard Reference Material.

  17. Principal component regression analysis of the relation between CIELAB color and monomeric anthocyanins in young Cabernet Sauvignon wines.

    Science.gov (United States)

    Han, Fu-Liang; Zhang, Wen-Na; Pan, Qiu-Hong; Zheng, Cheng-Rong; Chen, Hai-Yan; Duan, Chang-Qing

    2008-11-17

    Color is one of the key characteristics used to evaluate the sensory quality of red wine, and anthocyanins are the main contributors to color. Monomeric anthocyanins and CIELAB color values were investigated by HPLC-MS and spectrophotometry during fermentation of Cabernet Sauvignon red wine, and principal component regression (PCR), a statistical tool, was used to establish a linkage between the detected anthocyanins and wine coloring. The results showed that 14 monomeric anthocyanins could be identified in wine samples, and all of these anthocyanins were negatively correlated with the L*, b* and H*ab values, but positively correlated with a* and C*ab values. On an equal concentration basis for each detected anthocyanin, cyanidin-3-O-glucoside (Cy3-glu) had the most influence on CIELAB color value, while malvidin 3-O-glucoside (Mv3-glu) had the least. The color values of various monomeric anthocyanins were influenced by their structures, substituents on the B-ring, acyl groups on the glucoside and the molecular steric structure. This work develops a statistical method for evaluating correlation between wine color and monomeric anthocyanins, and also provides a basis for elucidating the effect of intramolecular copigmentation on wine coloring.

  18. Principal Component Regression Analysis of the Relation Between CIELAB Color and Monomeric Anthocyanins in Young Cabernet Sauvignon Wines

    Directory of Open Access Journals (Sweden)

    Chang-Qing Duan

    2008-11-01

    Full Text Available Color is one of the key characteristics used to evaluate the sensory quality of red wine, and anthocyanins are the main contributors to color. Monomeric anthocyanins and CIELAB color values were investigated by HPLC-MS and spectrophotometry during fermentation of Cabernet Sauvignon red wine, and principal component regression (PCR, a statistical tool, was used to establish a linkage between the detected anthocyanins and wine coloring. The results showed that 14 monomeric anthocyanins could be identified in wine samples, and all of these anthocyanins were negatively correlated with the L*, b* and H*ab values, but positively correlated with a* and C*ab values. On an equal concentration basis for each detected anthocyanin, cyanidin-3-O-glucoside (Cy3-glu had the most influence on CIELAB color value, while malvidin 3-O-glucoside (Mv3-glu had the least. The color values of various monomeric anthocyanins were influenced by their structures, substituents on the B-ring, acyl groups on the glucoside and the molecular steric structure. This work develops a statistical method for evaluating correlation between wine color and monomeric anthocyanins, and also provides a basis for elucidating the effect of intramolecular copigmentation on wine coloring.

  19. Alkaloids and Phenolic Compounds from Sida rhombifolia L. (Malvaceae) and Vasorelaxant Activity of Two Indoquinoline Alkaloids.

    Science.gov (United States)

    Chaves, Otemberg Souza; Teles, Yanna Carolina Ferreira; Monteiro, Matheus Morais de Oliveira; Mendes Junior, Leônidas das Graças; Agra, Maria de Fátima; Braga, Valdir de Andrade; Silva, Tânia Maria Sarmento; Souza, Maria de Fátima Vanderlei de

    2017-01-06

    The follow-up of phytochemical and pharmacological studies of Sida rhombifolia L. (Malvaceae) aims to strengthen the chemosystematics and pharmacology of Sida genera and support the ethnopharmacological use of this species as hypotensive herb. The present work reports phytoconstituents isolated and identified from aerial parts of S. rhombifolia by using chromatographic and spectroscopic methods. The study led to the isolation of scopoletin (1), scoporone (2), ethoxy-ferulate (3), kaempferol (4), kaempferol-3-O-β-d-glycosyl-6''-α-d-rhamnose (5), quindolinone (6), 11-methoxy-quindoline (7), quindoline (8), and the cryptolepine salt (9). The alkaloids quindolinone (6) and cryptolepine salt (9) showed vasorelaxant activity in rodent isolated mesenteric arteries.

  20. Pyrrolizidine Alkaloids in Adenostyles alliariae and A. glabra from the Austrian Alps.

    Science.gov (United States)

    Chizzola, Remigius

    2015-07-01

    The alkaloid content of Adenostyles alliariae and A. glabra (Asteraceae) has been evaluated. Both species contain toxic macrocyclic unsaturated pyrrolizidine alkaloids with seneciphylline as the main compound accounting for more than 90% of the alkaloid fraction in all above ground plant parts. Further alkaloids were spartioidine, acetyl-senciphylline and senecionine. Inflorescences showed the highest alkaloid contents with 21.1 and 13.4 mg/g in A. alliariae and A. glabra, respectively. Stems and leaves had 2-3 times lower contents. Therefore, these Adenostyles species must be considered as highly toxic plants.

  1. Alkaloids from single skins of the Argentinian toad Melanophryniscus rubriventris (ANURA, BUFONIDAE): An unexpected variability in alkaloid profiles and a profusion of new structures.

    Science.gov (United States)

    Garraffo, H Martin; Andriamaharavo, Nirina R; Vaira, Marcos; Quiroga, María F; Heit, Cecilia; Spande, Thomas F

    2012-12-01

    GC-MS analysis of single-skins of ten Melanophryniscus rubriventris toads (five collections of two toads each) captured during their breeding season in NW Argentina has revealed a total of 127 alkaloids of which 56 had not been previously detected in any frog or toad. Included among these new alkaloids are 23 new diastereomers of previously reported alkaloids. What is particularly distinguishing about the alkaloid profiles of these ten collections is the occurrence of many of the alkaloids, whether known or new to us, in only one of the ten skins sampled, despite two skins being obtained from each breeding site of the five populations. Many of the alkaloids are of classes known to have structures with branched-chains (e.g. pumiliotoxins and tricyclic structures) that are considered to derive from dietary mites. A large number of previously reported and new alkaloids are also of unclassified structures. Only a very few 3,5-disubstituted-indolizidine or -pyrrolizidine alkaloids are observed that have a straight-chain carbon skeleton and are likely derived from ant prey. The possible relationship of these collections made during the toad's brief breeding episodes to sequestration of dietary arthropods and individual alkaloid profiles is discussed.

  2. Histochemical Investigation and Kinds of Alkaloids in Leaves of Different Developmental Stages in Thymus quinquecostatus

    Directory of Open Access Journals (Sweden)

    Haiting Jing

    2014-01-01

    Full Text Available Thymus quinquecostatus, with more medical value, is a kind of wild plants. In order to exploit and utilize this plant, we studied the species and locations of alkaloids in its leaves. In this paper, histochemical study of leaves at different developing stages was taken to localize the alkaloids. Meanwhile, the kinds and content of alkaloids in leaves were identified using GC-MS technique. It was found that there were two kinds of glandular trichomes, namely, peltate trichomes and capitate trichomes, on the surface of leaves, and their secretory cells could secrete alkaloids. Results showed that trichomes could secrete alkaloids as soon as the first pair of leaves formed, and there were altogether 18 kinds of alkaloids identified by GC-MS. Nearly all of these alkaloids of leaves at different developing stages were distinct from each other, except one, 3-methoxy-a-methyl-benzeneethanamine, persists at different developing stages with high concentration.

  3. Reactivity studies on [Cp'FeI]2: monomeric amido, phenoxo, and alkyl complexes.

    Science.gov (United States)

    Walter, Marc D; White, Peter S

    2012-11-05

    A series of monomeric mono(cyclopentadienyl) iron amido, phenoxo, and alkyl complexes were synthesized, and their structure and reactivity are presented. The iron(II) centers in these 14VE one-legged piano stool complexes are high spin (S = 2) in solid state and solution independent of solvent. The silylamide compound [Cp'FeN(SiMe(3))(2)] (2a, Cp' = 1,2,4-(Me(3)C)(3)C(5)H(2)) is an excellent starting material for the reaction with more acidic substrates such as phenols. Sterically encumbered phenols 2,6-(Me(3)C)(2)(4-R)C(6)H(2)OH (R = H, Me, and tBu) were investigated. In all cases monomeric iron phenoxo half-sandwich complexes [Cp'FeOR'] (4-R) are initially formed. Rearrangement of 4-R to the diamagnetic oxocyclohexadienyl complex [Cp'Fe(η(5)-O═C(6)H(2)R'(2)R")] (5-R) is observed for 2,6-(Me(3)C)(2)(4-R)C(6)H(2)OH (R = H and Me) and the Gibbs free enthalpy of activation (ΔG(‡)) was determined. In contrast this rearrangement is inhibited when the 4-position is blocked by a tBu group. Removing the steric bulk from the 2,6-positions leads to the formation of a μ-phenoxo dimer, [Cp'Fe(μ-OC(6)H(3)tBu(2)-3,5)](2) (5). Density functional theory (DFT) was used to further elucidate the structure-reactivity relationship in these molecules. The one-legged piano stool anilido complex [Cp'Fe(NHC(6)H(2)tBu(3)-2,4,6)] (7) is not accessible via acid-base reaction between 2a and H(2)NC(6)H(2)tBu(3)-2,4,6, but can be prepared by conventional salt metathesis reaction from [Cp'FeI](2) and [Li(NHC(6)H(2)tBu(3)-2,4,6)(OEt(2))](2). In contrast, reaction of 2a with Ph(2)NH yields the bimetallic [Cp'Fe(N,C-κ(1),η(5)-C(6)H(5)NPh)Fe(N-κ(1)-NPh(2))Cp'] (8) which combines two iron centers in the same oxidation state (+2), but different spin-states (S = 0 and S = 2) which is reflected in very different Cp(cent)-Fe distances of 1.68 and 2.04 Å, respectively. A monomeric iron alkyl half-sandwich complex [Cp'FeCH(SiMe(3))(2)] (9) was prepared that exhibits no reactivity toward H(2), C

  4. Metabolic Engineering of Tropane Alkaloid Biosynthesis in Plants

    Institute of Scientific and Technical Information of China (English)

    Lei ZHANG; Guo-Yin KAI; Bei-Bei LU; Han-Ming ZHANG; Ke-Xuan TANG; Ji-Hong JIANG; Wan-Sheng CHEN

    2005-01-01

    Over the past decade, the evolving commercial importance of so-called plant secondary metabolites has resulted in a great interest in secondary metabolism and, particularly, in the possibilities to enhance the yield of fine metabolites by means of genetic engineering. Plant alkaloids, which constitute one of the largest groups of natural products, provide many pharmacologically active compounds. Several genes in the tropane alkaloids biosynthesis pathways have been cloned, making the metabolic engineering of these alkaloids possible. The content of the target chemical scopolamine could be significantly increased by various approaches, such as introducing genes encoding the key biosynthetic enzymes or genes encoding regulatory proteins to overcome the specific rate-limiting steps. In addition, antisense genes have been used to block competitive pathways. These investigations have opened up new, promising perspectives for increased production in plants or plant cell culture. Recent achievements have been made in the metabolic engineering of plant tropane alkaloids and some new powerful strategies are reviewed in the present paper.

  5. An immunosuppressive tryptophan-derived alkaloid from Lepidagathis cristata.

    Science.gov (United States)

    Ravikanth, V; Niranjan Reddy, V L; Ramesh, P; Prabhakar Rao, T; Diwan, P V; Khar, A; Venkateswarlu, Y

    2001-12-01

    An immunosuppressive, tryptophan-derived alkaloid cristatin A (1), and two known compounds, cycloartenol and stigmasta-5,11(12)-diene-3 beta-ol, were isolated from the whole plant Lepidagathis cristata Willd. The structures of the isolates were established by interpretation of their spectral data.

  6. Diterpenoid alkaloid toxicosis in cattle in the Swiss Alps.

    Science.gov (United States)

    Puschner, Birgit; Booth, Marcia C; Tor, Elizabeth R; Odermatt, Arnold

    2002-02-01

    Between 1995 and 1999, several cattle of a group of 80 heifers died acutely on a pasture in the Swiss Alps. The animals were Found dead between July 9th and 15th eachyear. Only 1 animal was examined on post-mortem, and no significant lesions were found. Aconitum vulpera, A napellus, and Delphinium elatum were identified in the pasture. The presence of diterpenoid alkaloid-containing plants in the pasture, the rapid death of the animals, and the lack of pathologic lesions suggested diterpenoid alkaloid toxicosis as a cause of death. A multiresidue alkaloid screen using gas chromatography with a mass spectrometric detector was employed on rumen, abomasal, small intestine, and cecal contents from the I heifer. Deltaline, deltamine, and lycoctonine were identified. Aconitine was found in all gastrointestinal samples using a sensitive and highly specific liquid chromatography/mass spectrometry methodology for aconitine analysis. The findings ofditerpenoid alkaloids in the gastrointestinal contents confirmed exposure to Delphinium and Aconitum spp, possibly resulting in sudden death.

  7. Revised NMR data for incartine: an alkaloid from Galanthus elwesii.

    Science.gov (United States)

    Berkov, Strahil; Reyes-Chilpa, Ricardo; Codina, Carles; Viladomat, Francesc; Bastida, Jaume

    2007-07-12

    Phytochemical studies on Galanthus elwesii resulted in the isolation of five alkaloids: incartine, hordenine, hippeastrine, 8-O-demethylhomolycorine and lycorine. The NMR data given previously for incartine were revised and completed by two-dimensional 1H-1H and 1H-13C chemical shift correlation experiments. In vitro studies on the bioactivity of incartine were carried out.

  8. Revised NMR data for Incartine: an Alkaloid from Galanthus elwesii

    Directory of Open Access Journals (Sweden)

    Jaume Bastida

    2007-07-01

    Full Text Available Phytochemical studies on Galanthus elwesii resulted in the isolation of five alkaloids: incartine, hordenine, hippeastrine, 8-O-demethylhomolycorine and lycorine. The NMR data given previously for incartine were revised and completed by two-dimensional 1H-1H and 1H-13C chemical shift correlation experiments. In vitro studies on the bioactivity of incartine were carried out.

  9. Ochrocephalamine A, a new quinolizidine alkaloid from Oxytropis ochrocephala Bunge.

    Science.gov (United States)

    Liu, Li-Na; Ran, Jian-Qiang; Li, Li-Jun; Zhao, Yu; Goto, Masuo; Morris-Natschke, Susan L; Lee, Kuo-Hsiung; Zhao, Bao-Yu; Tan, Cheng-Jian

    2016-11-16

    One dimeric matrine-type alkaloid, ochrocephalamine A (1), was isolated from the poisonous plant Oxytropis ochrocephala Bunge. Its structure was elucidated by spectroscopic data and single-crystal X-ray diffraction. The insecticidal and cytotoxic activities of 1 were evaluated.

  10. Effects of motherwort alkaloids on rat ear acne

    Directory of Open Access Journals (Sweden)

    Miao Mingsan

    2016-04-01

    Full Text Available The aim of this study was to explore the effects of motherwort alkaloids on rat ear acne. The rats that were administered high, medium, and low doses of motherwort alkaloids, tanshinone capsules, a model and a control group. Each group of rats was subjected to gavage once daily for 14 consecutive days. On the first day of testing, the control and model groups were administered an intradermal auricle injection of sterilized saline solution and the remaining groups were administered an intradermal auricle injection of Staphylococcus epidermidis in addition to the gavage. The thicknesses of the rats’ auricles were measured for five consecutive days following the injections. Anticoagulated blood was used for erythrocyte rheology index measurement. In addition, the entire ear of each rat was removed for morphological examination. Compared to the model group, the group administered motherwort alkaloids exhibited significantly reduced swelling, improved localized auricle proliferation, and reduced blood viscosity. This result suggests motherwort alkaloids are effective in rat ear acne.

  11. New alkaloid from Streptomyces koyangensis residing in Odontotermes formosanus.

    Science.gov (United States)

    Bi, Shu-Feng; Guo, Zhi-Kai; Jiang, Nan; Jiao, Rui-Hua; Ge, Hui-Ming; Tan, Ren-Xiang

    2013-01-01

    A new alkaloid was isolated from the ethyl acetate extract of the culture of a termite-associated Streptomyces koyangensis BY-4. The structure of 1 was elucidated by using MS, NMR, electronic circular dichroism data, and computational approaches. Compound 1 showed weak antimicrobial activities against a panel of test microbes.

  12. Ergovaline, an endophytic alkaloid. 1. Animal physiology and metabolism

    Science.gov (United States)

    Ergovaline is an ergot alkaloid found in some endophyte-infected ryegrasses and has been implicated in the expression of ergotism-like symptoms of grazing livestock, as well as in the protection of the plant against invertebrate predation and abiotic stresses. These selection pressures have resulted...

  13. Indole Alkaloids from the Roots of Ervatamia hainanensis

    Institute of Scientific and Technical Information of China (English)

    Jian Peng HUANG; Zi Ming FENG; Chong Fei ZHENG; Pei Cheng ZHANG; Yang Min MA

    2006-01-01

    Two new indole alkaloids, named ibogamine-18-carboxylic acid, 3, 4-didehydro-7, 8-dioxo-methyl ester 1, ibogamine-18-carboxylic acid, 16, 17-didehydro-9, 17-dihydro-9-hydroxy-(2-oxopropyl)-methyl ester 2, were isolated from Ervatamia hainanensis. Their structures were elucidated on the basis of spectroscopic methods.

  14. Dasycarine, a New Quinoline Alkaloid from Dictamnus dasycarpus

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Dasycarine, a new quinoline alkaloid along with five known compounds, dictamine, dihydroobacunone, obacunone, fraxinellone and b -sitosterol, were isolated from Dictamnus dasycarpus. The structure of dasycarine was identified as 4, 5, 8- trimethoxyl -3- (3- methyl -2- butenyl)- 2- quinone by 1D and 2D NMR techniques.

  15. New Diterpenoid Alkaloids from the Roots of Delphinium tiantaishanense

    Directory of Open Access Journals (Sweden)

    Feng-Peng Wang

    2007-03-01

    Full Text Available Four new diterpenoid alkaloids: tiantaishansine (1, tiantaishannine (2, tiantaishanmine (3, and tiantaishandine (4 have been isolated from the roots of Delphinium tiantaishan. Their structures were elucidated by chemical evidence andspectral analyses, including ESI-MS, HR-EI-MS, 1D- and 2D-NMR.

  16. The Raputindoles: Novel Cyclopentyl Bisindole Alkaloids from Raputia simulans

    Science.gov (United States)

    A novel class of bisindole alkaloids is established by the isolation and structural determination of Raputindoles A-D (1-4) from the Amazonian plant Raputia simulans Kallunki (Rutaceae). Complete spectroscopic characterization was accomplished by means of NMR spectroscopy and APCI (+) HRMS. Raputind...

  17. Australine, a pyrrolizidine alkaloid that inhibits amyloglucosidase and glycoprotein processing

    Energy Technology Data Exchange (ETDEWEB)

    Tropea, J.E.; Molyneux, R.J.; Kaushal, G.P.; Pan, Y.T.; Mitchell, M.; Elbein, A.D. (Univ. of Texas Health Science Center, San Antonio (USA))

    1989-03-07

    Australine is a polyhydroxylated pyrrolizidine alkaloid that was isolated from the seeds of the Australian tree Castanospermum australe and characterized by NMR and X-ray diffraction analysis. Since swainsonine and catanospermine are polyhydroxylated indolizidine alkaloids that inhibit specific glycosidases, the authors tested australine against a variety of exoglycosidases to determine whether it would inhibit any of these enzymes. This alkaloid proved to be a good inhibitor of the {alpha}-glucosidase amyloglucosidase (50% inhibition at 5.8 {mu}M), but it did not inhibit {beta}-glucosidase, {alpha}- or {beta}-mannosidase, or {alpha}- or {beta}-galactosidase. The inhibition of amyloglucosidase was of a competitive nature. Australine also inhibited the glycoprotein processing enzyme glucosidase I, but had only slight activity toward glucosidase II. When incubated with cultured cells, this alkaloid inhibited glycoprotein processing at the glucosidase I step and caused the accumulation of glycoproteins with Glc{sub 3}Man{sub 7-9}(GlcNAc){sub 2}-oligosaccharides.

  18. Pyrrolizidine alkaloids in medicinal tea of Ageratum conyzoides

    Directory of Open Access Journals (Sweden)

    Cristiane F. Bosi

    2013-06-01

    Full Text Available It is now widely-recognized that the view that herbal remedies have no adverse effects and/or toxicity is incorrect; some traditionally-used plants can present toxicity. The well-established popular use of Ageratum conyzoides has led to its inclusion in a category of medicinal crude drugs created by the Brazilian Health Surveillance Agency. Ageratum belongs to the Eupatorieae tribe, Asteraceae, and is described as containing toxic pyrrolizidine alkaloids. Aqueous extracts of Ageratum conyzoides L. harvested in Brazil (commercial, flowering and non-flowering samples were prepared according to the prescribed method and analyzed by HPLC-HRMS. The pyrrolizidine alkaloids lycopsamine, dihydrolycopsamine, and acetyl-lycopsamine and their N-oxides, were detected in the analyzed extracts, lycopsamine and its N-oxide being known hepatotoxins and tumorigens. Together with the pyrrolizidine alkaloids identified by HPLC-HRMS, thirteen phenolic compounds were identified, notably, methoxylated flavonoids and chromenes. Toxicological studies on A. conyzoides are necessary, as is monitoring of its clinical use. To date, there are no established safety guidelines on pyrrolizidine alkaloids-containing plants, and their use in Brazil.

  19. A Short Synthetic Route to the Calystegine Alkaloids

    DEFF Research Database (Denmark)

    Skaanderup, Philip Robert; Madsen, Robert

    2003-01-01

    An efficient strategy is described for the synthesis of enantiopure calystegine alkaloids. The key step employs a zinc-mediated fragmentation of benzyl-protected methyl 6-iodo-glycosides followed by in situ formation of the benzyl imine and Barbier-type allylation with zinc, magnesium, or indium...

  20. Dichlorinated and Brominated Rugulovasines, Ergot Alkaloids Produced by Talaromyces wortmannii

    DEFF Research Database (Denmark)

    Soman De Medeiros, Lívia; da Silva, José Vinícius; Abreu, Lucas Magalhães

    2015-01-01

    UHPLC-DAD-HRMS based dereplication guided the detection of new halogenated alkaloids co-produced by Talaromyces wortmannii. From the fungal growth in large scale, the epimers 2,8-dichlororugulovasines A and B were purified and further identified by means of a HPLC-SPE/NMR hyphenated system...

  1. Reviewing colchicaceae alkaloids – perspectives of evolution on medicinal chemistry

    DEFF Research Database (Denmark)

    Larsson, Sonny; Rønsted, Nina

    2014-01-01

    . In this review an approach of taking phylogenetic classification into account in evaluating colchicine and related phenethylisoquinoline alkaloids from the family Colchicaceae will be applied. Following on the trends of utilizing evolutionary reasoning in inferring mechanisms in eg. drug resistance in cancer...

  2. In vitro cytotoxicity of various dehydropyrrolizidine ester alkaloids

    Science.gov (United States)

    Dehydropyrrolizidine alkaloids (DHPAs) are plant-derived hepato-, pneumo- and geno-toxins that are carcinogenic in several species. Because of the difficulty in isolating sufficient DHPA for toxicological studies, there are few direct comparisons of toxicity. The objectives of this study was to de...

  3. Biosynthesis of the defensive alkaloid cicindeloine in Stenus solutus beetles

    Science.gov (United States)

    Schierling, Andreas; Dettner, Konrad; Schmidt, Jürgen; Seifert, Karlheinz

    2012-08-01

    To protect themselves from predation and microorganismic infestation, rove beetles of the genus Stenus produce and store bioactive alkaloids like stenusine, 3-(2-methyl-1-butenyl)pyridine, and cicindeloine in their pygidial glands. The biosynthesis of stenusine and 3-(2-methyl-1-butenyl)pyridine was previously investigated in Stenus bimaculatus and Stenus similis, respectively. Both molecules follow the same biosynthetic pathway, where the N-heterocyclic ring is derived from l-lysine and the side chain from l-isoleucine. The different alkaloids are finally obtained by slight modifications of shared precursor molecules. The piperideine alkaloid cicindeloine occurs as a main compound additionally to ( E)-3-(2-methyl-1-butenyl)pyridine and traces of stenusine in the pygidial gland secretion of Stenus cicindeloides and Stenus solutus. Feeding of S. solutus beetles with [D,15N]-labeled amino acids followed by GC/MS analysis techniques showed that cicindeloine is synthesized via the identical pathway and precursor molecules as the other two defensive alkaloids.

  4. Isolation of a new carboline alkaloid from Trigonostemon lii.

    Science.gov (United States)

    Yang, Hongmei; Luo, Yanping; Zhao, Hongmei; Wu, Jichun; Chen, Yegao

    2016-01-01

    A new carboline alkaloid, 1-(7-methoxy-quinolinyl-4'-yl)-3,4-dihydro-β-carboline (1), was isolated from the leaves and twigs of Trigonostemon lii Y.T. Chang, together with three known ones, trigonostemonines C and D (2 and 3), and trigonoliimine A (4). Their structures were elucidated by spectroscopic analyses, including 2D-NMR techniques.

  5. ALKALOIDS OF THE SEDUM ACRE-GROUP (CRASSULACEAE)

    NARCIS (Netherlands)

    STEVENS, JF; THART, H; HENDRIKS, H; MALINGRE, TM

    1993-01-01

    The 16 species of the Sedum acre-group were investigated for the presence of alkaloids. They are S. acre of S. ser. Acria, S. alpestre, S. annuum, S. apoleipon, S. borissovae, S. euxinum, S. grisebachii, S. laconicum, S. multiceps, S. sexangulare, S. tuberiferum, S. tuberosum, S. ursi, and S. urvill

  6. A Concise Synthesis of Monoterpene Pyridine Alkaloid Aucubinine B

    Institute of Scientific and Technical Information of China (English)

    杨晓霞; 赵景瑞; 贾学顺; 杨力维; 翟宏斌

    2003-01-01

    Aucubinine B (4), a monoterpene alkaloid obtained from the metabolites of aucubin in the presence of human intestinal bacteria, has been synthesized from 3-bromo-4-pyridinecarboxaldehyde (5) in four steps with 39% overall yield. The construction of the cyclopenta[c]pyridine intermediate (7) was realized by an intramolecular Heck reaction.

  7. Repellence and attraction of Apis mellifera foragers by nectar alkaloids

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    Hroncová Z.

    2016-03-01

    Full Text Available Plant secondary metabolites present naturally in nectar, such as alkaloids, may change the behavioural responses of floral visitors and affect pollination. Some studies have shown that nectar containing low concentrations of these secondary metabolites is preferred by honey bee foragers over pure nectar. However, it remains unclear whether this is caused by dependence or addictive behaviour, a simple taste preference, or by other conditions such as self-medication. In our choice experiment, free-flying bees were presented with artificial flowers holding 20% sucrose containing 0.5−50 μg ml−1 of one of the naturally occurring nectar alkaloids - caffeine, nicotine, senecionine, and gelsemine. Nectar uptake was determined by weighing each flower and comparing the weight to that of the control flower. Our experimental design minimized memorizing and marking; despite this, caffeine was significantly preferred at concentrations 0.5−2 μg ml−1 over control nectar; this preference was not observed for other alkaloids. All of the compounds tested were repellent at concentrations above 5 μg ml−1. We confirmed previous reports that bees exhibit a preference for caffeine, and hypothesize that this is not due only to addictive behaviour but is at least partially mediated by taste preference. We observed no significant preference for nicotine or any other alkaloid.

  8. Synthesis and structural characterization of monomeric mercury(II) selenolate complexes derived from 2-phenylbenzamide ligands.

    Science.gov (United States)

    Patel, Saket; Meenakshi; Hodage, Ananda S; Verma, Ajay; Agrawal, Shailendra; Yadav, Abhimanyu; Kumar, Sangit

    2016-03-07

    Monomeric Hg(II) selenolate complexes derived from 2-phenylbenzamide ligands were prepared by oxidative addition of diselenides [{C6H4(CONR2)Se}2, R = Me, Et, iPr] to elemental Hg and reductive cleavage of the Se–N bond of isoselenazolone derivatives [(NO2)C6H3(CONSe)R, (R = allyl, nbutyl)] followed by the treatment with HgCl2. The complexes have been characterized by multinuclear NMR (1H, 13C and 77Se) spectroscopy and mass spectrometry which suggest the monomeric form of these in solution. The molecular structures of diselenides [C6H4(CONR2)Se]2 and mercury selenolates [Hg{(NO2)C6H3(CONH-C3H5) Se}2], [Hg{C6H4(CONiPr2)Se}2] and [Hg{C6H4(CONMe2)Se}2] were established by a single crystal X-ray diffraction study. Diselenides show strong intramolecular non-bonded Se⋯O interactions, which are influenced by the nature of C(O)NR̲2 and decrease with the sterically bulky alkyl substituent (Se⋯O =2.823 Å for R = di-Me, 2.760 Å for R = allyl, and 3.157 Å for R = di-iPr). Mercury complexes derived from less bulky 2-phenyl-N,N-dialkylbenzamide ligands associated with poor or no intramolecular nonbonded Hg⋯O interactions (4.91 Å for R = di-Me, 4.199 Å for R = allyl) and instead strong intermolecular Hg⋯O [2.792(3) and 2.820(4) Å] for di-Me and allyl and Hg⋯Se [3.3212(5) and 3.4076(8) Å] interactions were observed which lead to a dimeric form in the crystals. On the other hand, the mercury complex derived from the sterically bulky diisopropyl amide ligand shows a strong intramolecular non-bonded Hg⋯O (2.860 Å) interaction, adopts linear geometry and exists as a monomer. Thermogravimetric analysis (TGA) of the mercury selenolate complexes revealed two-step decomposition which leads to the formation of HgSe. The mercury selenolate complex 3c derived from the sterically bulky 2-phenyl-N,Ndiisopropylbenzamide ligand decomposed to give HgSe in the range of 220-300 °C.

  9. 11 Efficacy and Tolerability of HDM Injective Immunotherapy With Monomeric Allergoid

    Science.gov (United States)

    Compalati, Enrico; Atzeni, Isabella; Cabras, Sergio; Fancello, Paolo; Gaspardini, Giulio; Longo, Rocco; Patella, Vincenzo; Tore, Giorgio

    2012-01-01

    Background Subcutaneous immunotherapy (SCIT) is an effective treatment of respiratory allergy and carbamylated monomeric allergoids (monoids), by virtue of their reduced IgE-binding activity, resulted clinically safe by sublingual administration. Purpose of this study was to investigate the efficacy and tolerability of immunotherapy with house dust mites (HDM) monoid administered by injective route in patients with allergic rhinoconjunctivitis (AR). Methods A preparation of 0.70 mL of 10 BU/mL containing modified extract with 50% Dermatophagoides pteronyssinus and 50% Dermatophagoides farinae (amount of major allergen: 4 μg of group 1 per milliliter) was delivered monthly for 12 months, following a 5-week build-up induction phase (0.10–0.20–0.30–0.50–0.70 mL), to 58 patients (60% males, mean age 25.1 ± 12.7) suffering from AR due to mites for at least 2 years, whereas 60 patients with similar baseline characteristics were observed as controls. All patients were allowed to assume traditional drug therapy for their condition. At the end of the study changes from baseline in symptoms scores, in number of days with drug assumption, in severity of AR (according to ARIA classification) were compared between the 2 groups; moreover an overall assessment of clinical efficacy and tolerability was based on patients' and physicians' judgements (unsatisfactory, mild, good, optimal). Results In respect to baseline both groups showed, after 1 year, an improvement in symptoms score (P < 0.001) with a significant difference in favour of SCIT group (P < 0.05). Days of drug intake were significantly lower in patients receiving SCIT (P < 0.05). The number of patients with severe AR decreased in the first group while no variation was observed in controls. The subjective clinical overall assessment was optimal in 31 cases and good in 24 according to physicians' and patients' judgements; similarly 38 patients judged tolerability as optimal and 18 as good, whereas according to

  10. Holistic versus monomeric strategies for hydrological modelling of human-modified hydrosystems

    Science.gov (United States)

    Nalbantis, I.; Efstratiadis, A.; Rozos, E.; Kopsiafti, M.; Koutsoyiannis, D.

    2011-03-01

    The modelling of human-modified basins that are inadequately measured constitutes a challenge for hydrological science. Often, models for such systems are detailed and hydraulics-based for only one part of the system while for other parts oversimplified models or rough assumptions are used. This is typically a bottom-up approach, which seeks to exploit knowledge of hydrological processes at the micro-scale at some components of the system. Also, it is a monomeric approach in two ways: first, essential interactions among system components may be poorly represented or even omitted; second, differences in the level of detail of process representation can lead to uncontrolled errors. Additionally, the calibration procedure merely accounts for the reproduction of the observed responses using typical fitting criteria. The paper aims to raise some critical issues, regarding the entire modelling approach for such hydrosystems. For this, two alternative modelling strategies are examined that reflect two modelling approaches or philosophies: a dominant bottom-up approach, which is also monomeric and, very often, based on output information, and a top-down and holistic approach based on generalized information. Critical options are examined, which codify the differences between the two strategies: the representation of surface, groundwater and water management processes, the schematization and parameterization concepts and the parameter estimation methodology. The first strategy is based on stand-alone models for surface and groundwater processes and for water management, which are employed sequentially. For each model, a different (detailed or coarse) parameterization is used, which is dictated by the hydrosystem schematization. The second strategy involves model integration for all processes, parsimonious parameterization and hybrid manual-automatic parameter optimization based on multiple objectives. A test case is examined in a hydrosystem in Greece with high complexities

  11. Holistic versus monomeric strategies for hydrological modelling of human-modified hydrosystems

    Directory of Open Access Journals (Sweden)

    I. Nalbantis

    2011-03-01

    Full Text Available The modelling of human-modified basins that are inadequately measured constitutes a challenge for hydrological science. Often, models for such systems are detailed and hydraulics-based for only one part of the system while for other parts oversimplified models or rough assumptions are used. This is typically a bottom-up approach, which seeks to exploit knowledge of hydrological processes at the micro-scale at some components of the system. Also, it is a monomeric approach in two ways: first, essential interactions among system components may be poorly represented or even omitted; second, differences in the level of detail of process representation can lead to uncontrolled errors. Additionally, the calibration procedure merely accounts for the reproduction of the observed responses using typical fitting criteria. The paper aims to raise some critical issues, regarding the entire modelling approach for such hydrosystems. For this, two alternative modelling strategies are examined that reflect two modelling approaches or philosophies: a dominant bottom-up approach, which is also monomeric and, very often, based on output information, and a top-down and holistic approach based on generalized information. Critical options are examined, which codify the differences between the two strategies: the representation of surface, groundwater and water management processes, the schematization and parameterization concepts and the parameter estimation methodology. The first strategy is based on stand-alone models for surface and groundwater processes and for water management, which are employed sequentially. For each model, a different (detailed or coarse parameterization is used, which is dictated by the hydrosystem schematization. The second strategy involves model integration for all processes, parsimonious parameterization and hybrid manual-automatic parameter optimization based on multiple objectives. A test case is examined in a hydrosystem in Greece

  12. Peculiarities of tropane alkaloids determination in Datura Stramonium L. leaves

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    Володимир Анатолійович Міщенко

    2015-12-01

    Full Text Available The questions of the search, pharmacological activity and standardization of natural extracts are appropriate and important for national pharmaceutical science and practice. Since 2000, one of the key points of the Action Plan to ensure the integration of Ukraine into the European Union is development of the State Pharmacopoeia of Ukraine harmonized with the European Pharmacopoeia (PhEur.Aim: A comparative analysis of herbal material according to the methods for tropane group alkaloids determination, as described in the PhEur and in the 11th Edition of USSR Pharmacopoeia Monographs «Stramonium leaf».Methods: Datura leaves samples have been harvested during 2010-2012 in different regions of Ukraine for experimental research. Identification of tropane group alkaloids was carried out by the method of thin-layer chromatography (TLC and by Vitali-Morin colour reaction. According to the PhEur method, firstly Dragendorff reagent and then Sodium nitrite solutions were used for the TLC plates spraying. Alkaloids assay was carried out by alkalimetry method with indicator determination of equivalence point.Results: Datura leaves qualitative features, defined by PhEur and the 11th Edition of USSR Pharmacopoeia Monographs «Stramonium leaf», as well as their rationing have been analyzed. Certain differences concerning regulated quality parameters of herbal material have been determined. A comparative analysis of the natural extracts by described in the given normative documents methods for determination of tropane group alkaloids content has been done. After spraying the TLC plates with Sodium nitrite solution, red-brown zones corresponding Hyoscyamine were determined. Hyoscine zones were characterized by less intense color. As a result of quantitative determination it was determined that the alkaloids content in analyzed Datura leaves samples was within the limits regulated by the PhEur and the 11th Edition of USSR Pharmacopoeia – more than 0

  13. Ibogan, tacaman, and cytotoxic bisindole alkaloids from tabernaemontana. Cononusine, an iboga alkaloid with unusual incorporation of a pyrrolidone moiety.

    Science.gov (United States)

    Lim, Kuan-Hon; Raja, Vijay J; Bradshaw, Tracey D; Lim, Siew-Huah; Low, Yun-Yee; Kam, Toh-Seok

    2015-05-22

    Six new indole alkaloids, viz., cononusine (1, a rare example of an iboga-pyrrolidone conjugate), ervaluteine (2), vincamajicine (3), tacamonidine (4), 6-oxoibogaine (5), and N(4)-chloromethylnorfluorocurarine chloride (6), and two new vobasinyl-iboga bisindole alkaloids, ervatensines A (7) and B (8), in addition to other known alkaloids, were isolated from the stem-bark extract of the Malayan Tabernaemontana corymbosa. The structures of these alkaloids were established on the basis of NMR and MS analyses and, in one instance (7), confirmed by X-ray diffraction analysis. Vincamajicine (3) showed appreciable activity in reversing multidrug resistance in vincristine-resistant KB cells (IC50 2.62 μM), while ervatensines A (7) and B (8) and two other known bisindoles displayed pronounced in vitro growth inhibitory activity against human KB cells (IC50 < 2 μM). Compounds 7 and 8 also showed good growth inhibitory activity against A549, MCF-7, MDA-468, HCT-116, and HT-29 cells (IC50 0.70-4.19 μM). Cell cycle and annexin V-FITC apoptosis assays indicated that compounds 7 and 8 inhibited proliferation of HCT-116 and MDA-468 cells, evoking apoptotic and necrotic cell death.

  14. Mapping the dynamics and nanoscale organization of synaptic adhesion proteins using monomeric streptavidin

    Science.gov (United States)

    Chamma, Ingrid; Letellier, Mathieu; Butler, Corey; Tessier, Béatrice; Lim, Kok-Hong; Gauthereau, Isabel; Choquet, Daniel; Sibarita, Jean-Baptiste; Park, Sheldon; Sainlos, Matthieu; Thoumine, Olivier

    2016-01-01

    The advent of super-resolution imaging (SRI) has created a need for optimized labelling strategies. We present a new method relying on fluorophore-conjugated monomeric streptavidin (mSA) to label membrane proteins carrying a short, enzymatically biotinylated tag, compatible with SRI techniques including uPAINT, STED and dSTORM. We demonstrate efficient and specific labelling of target proteins in confined intercellular and organotypic tissues, with reduced steric hindrance and no crosslinking compared with multivalent probes. We use mSA to decipher the dynamics and nanoscale organization of the synaptic adhesion molecules neurexin-1β, neuroligin-1 (Nlg1) and leucine-rich-repeat transmembrane protein 2 (LRRTM2) in a dual-colour configuration with GFP nanobody, and show that these proteins are diffusionally trapped at synapses where they form apposed trans-synaptic adhesive structures. Furthermore, Nlg1 is dynamic, disperse and sensitive to synaptic stimulation, whereas LRRTM2 is organized in compact and stable nanodomains. Thus, mSA is a versatile tool to image membrane proteins at high resolution in complex live environments, providing novel information about the nano-organization of biological structures. PMID:26979420

  15. SuperNova, a monomeric photosensitizing fluorescent protein for chromophore-assisted light inactivation.

    Science.gov (United States)

    Takemoto, Kiwamu; Matsuda, Tomoki; Sakai, Naoki; Fu, Donald; Noda, Masanori; Uchiyama, Susumu; Kotera, Ippei; Arai, Yoshiyuki; Horiuchi, Masataka; Fukui, Kiichi; Ayabe, Tokiyoshi; Inagaki, Fuyuhiko; Suzuki, Hiroshi; Nagai, Takeharu

    2013-01-01

    Chromophore-assisted light inactivation (CALI) is a powerful technique for acute perturbation of biomolecules in a spatio-temporally defined manner in living specimen with reactive oxygen species (ROS). Whereas a chemical photosensitizer including fluorescein must be added to specimens exogenously and cannot be restricted to particular cells or sub-cellular compartments, a genetically-encoded photosensitizer, KillerRed, can be controlled in its expression by tissue specific promoters or subcellular localization tags. Despite of this superiority, KillerRed hasn't yet become a versatile tool because its dimerization tendency prevents fusion with proteins of interest. Here, we report the development of monomeric variant of KillerRed (SuperNova) by direct evolution using random mutagenesis. In contrast to KillerRed, SuperNova in fusion with target proteins shows proper localization. Furthermore, unlike KillerRed, SuperNova expression alone doesn't perturb mitotic cell division. Supernova retains the ability to generate ROS, and hence promote CALI-based functional analysis of target proteins overcoming the major drawbacks of KillerRed.

  16. Hydrogen production from the monomeric sugars hydrolyzed from hemicellulose by Enterobacter aerogenes

    Energy Technology Data Exchange (ETDEWEB)

    Ren, Yunli; Wang, Jianji; Liu, Zhen; Ren, Yunlai; Li, Guozhi [School of Chemical Engineering and Pharmaceutics, Henan University of Science and Technology, Luoyang 471039, Henan (China)

    2009-12-15

    Relatively large percentages of xylose with glucose, arabinose, mannose, galactose and rhamnose constitute the hydrolysis products of hemicellulose. In this paper, hydrogen production performance of facultative anaerobe (Enterobacter aerogenes) has been investigated from these different monomeric sugars except glucose. It was shown that the stereoisomers of mannose and galactose were more effective for hydrogen production than those of xylose and arabinose. The substrate of 5 g/l xylose resulted in a relative high level of hydrogen yield (73.8 mmol/l), hydrogen production efficiency (2.2 mol/mol) and a maximum hydrogen production rate (249 ml/l/h). The hydrogen yield, hydrogen production efficiency and the maximum hydrogen production rate reached 104 mmol/l, 2.35 mol/mol and 290 ml/l/h, respectively, on a substrate of 10 g/l galactose. The hydrogen yields and the maximum hydrogen production rates increased with an increase of mannose concentrations and reached 119 mmol/l and 518 ml/l/h on the culture of 25 g/l mannose. However, rhamnose was a relative poor carbon resource for E. aerogenes to produce hydrogen, from which the hydrogen yield and hydrogen production efficiency were about one half of that from the mannose substrate. E. aerogenes was found to be a promising strain for hydrogen production from hydrolysis products of hemicellulose. (author)

  17. Generation of transgenic Wuzhishan miniature pigs expressing monomeric red fluorescent protein by somatic cell nuclear transfer.

    Science.gov (United States)

    Lu, Yue; Kang, Jin-Dan; Li, Suo; Wang, Wei; Jin, Jun-Xue; Hong, Yu; Cui, Cheng-du; Yan, Chang-Guo; Yin, Xi-Jun

    2013-08-01

    Red fluorescent protein and its variants enable researchers to study gene expression, localization, and protein-protein interactions in vitro in real-time. Fluorophores with higher wavelengths are usually preferred since they efficiently penetrate tissues and produce less toxic emissions. A recently developed fluorescent protein marker, monomeric red fluorescent protein (mRFP1), is particularly useful because of its rapid maturation and minimal interference with green fluorescent protein (GFP) and GFP-derived markers. We generated a pCX-mRFP1-pgk-neoR construct and evaluated the ability of mRFP1 to function as a fluorescent marker in transgenic Wuzhishan miniature pigs. Transgenic embryos were generated by somatic cell nuclear transfer (SCNT) of nuclei isolated from ear fibroblasts expressing mRFP1. Embryos generated by SCNT developed into blastocysts in vitro (11.65%; 31/266). Thereafter, a total of 685 transgenic embryos were transferred into the oviducts of three recipients, two of which became pregnant. Of these, one recipient had six aborted fetuses, whereas the other recipient gave birth to four offspring. All offspring expressed the pCX-mRFP1-pgk-neoR gene as shown by PCR and fluorescence in situ hybridization analysis. The transgenic pigs expressed mRFP1 in all organs and tissues at high levels. These results demonstrate that Wuzhishan miniature pigs can express mRFP1. To conclude, this transgenic animal represents an excellent model with widespread applications in medicine and agriculture.

  18. Retention mechanism for polycyclic aromatic hydrocarbons in reversed-phase liquid chromatography with monomeric stationary phases.

    Science.gov (United States)

    Rafferty, Jake L; Siepmann, J Ilja; Schure, Mark R

    2011-12-23

    Reversed-phase liquid chromatography (RPLC) is the foremost technique for the separation of analytes that have very similar chemical functionalities, but differ only in their molecular shape. This ability is crucial in the analysis of various mixtures with environmental and biological importance including polycyclic aromatic hydrocarbons (PAHs) and steroids. A large amount of effort has been devoted to studying this phenomenon experimentally, but a detailed molecular-level description remains lacking. To provide some insight on the mechanism of shape selectivity in RPLC, particle-based simulations were carried out for stationary phases and chromatographic parameters that closely mimic those in an experimental study by Sentell and Dorsey [J. Chromatogr. 461 (1989) 193]. The retention of aromatic hydrocarbons ranging in size from benzene to the isomeric PAHs of the formula C(18)H(12) was examined for model RPLC systems consisting of monomeric dimethyl octadecylsilane (ODS) stationary phases with surface coverages ranging from 1.6 to 4.2 μmol/m(2) (i.e., stationary phases yielding low to intermediate shape selectivity) in contact with a 67/33 mol% acetonitrile/water mobile phase. The simulations show that the stationary phase acts as a very heterogeneous environment where analytes with different shapes prefer different spatial regions with specific local bonding environments of the ODS chains. However, these favorable retentive regions cannot be described as pre-existing cavities because the chain conformation in these local stationary phase regions adapts to accommodate the analytes.

  19. Contribution of Monomeric Anthocyanins to the Color of Young Red Wine: Statistical and Experimental Approaches.

    Science.gov (United States)

    Han, Fu Liang; Li, Zheng; Xu, Yan

    2015-12-01

    Monomeric anthocyanin contributions to young red wine color were investigated using partial least square regression (PLSR) and aqueous alcohol solutions in this study. Results showed that the correlation between the anthocyanin concentration and the solution color fitted in a quadratic regression rather than linear or cubic regression. Malvidin-3-O-glucoside was estimated to show the highest contribution to young red wine color according to its concentration in wine, whereas peonidin-3-O-glucoside in its concentration contributed the least. The PLSR suggested that delphinidin-3-O-glucoside and peonidin-3-O-glucoside under the same concentration resulted in a stronger color of young red wine compared with malvidin-3-O-glucoside. These estimates were further confirmed by their color in aqueous alcohol solutions. These results suggested that delphinidin-3-O-glucoside and peonidin-3-O-glucoside were primary anthocyanins to enhance young red wine color by increasing their concentrations. This study could provide an alternative approach to improve young red wine color by adjusting anthocyanin composition and concentration.

  20. Model of a DNA-protein complex of the architectural monomeric protein MC1 from Euryarchaea.

    Directory of Open Access Journals (Sweden)

    Françoise Paquet

    Full Text Available In Archaea the two major modes of DNA packaging are wrapping by histone proteins or bending by architectural non-histone proteins. To supplement our knowledge about the binding mode of the different DNA-bending proteins observed across the three domains of life, we present here the first model of a complex in which the monomeric Methanogen Chromosomal protein 1 (MC1 from Euryarchaea binds to the concave side of a strongly bent DNA. In laboratory growth conditions MC1 is the most abundant architectural protein present in Methanosarcina thermophila CHTI55. Like most proteins that strongly bend DNA, MC1 is known to bind in the minor groove. Interaction areas for MC1 and DNA were mapped by Nuclear Magnetic Resonance (NMR data. The polarity of protein binding was determined using paramagnetic probes attached to the DNA. The first structural model of the DNA-MC1 complex we propose here was obtained by two complementary docking approaches and is in good agreement with the experimental data previously provided by electron microscopy and biochemistry. Residues essential to DNA-binding and -bending were highlighted and confirmed by site-directed mutagenesis. It was found that the Arg25 side-chain was essential to neutralize the negative charge of two phosphates that come very close in response to a dramatic curvature of the DNA.

  1. Crystal structure of monomeric photosystem II from Thermosynechococcus elongatus at 3.6-a resolution.

    Science.gov (United States)

    Broser, Matthias; Gabdulkhakov, Azat; Kern, Jan; Guskov, Albert; Müh, Frank; Saenger, Wolfram; Zouni, Athina

    2010-08-20

    The membrane-embedded photosystem II core complex (PSIIcc) uses light energy to oxidize water in photosynthesis. Information about the spatial structure of PSIIcc obtained from x-ray crystallography was so far derived from homodimeric PSIIcc of thermophilic cyanobacteria. Here, we report the first crystallization and structural analysis of the monomeric form of PSIIcc with high oxygen evolution capacity, isolated from Thermosynechococcus elongatus. The crystals belong to the space group C222(1), contain one monomer per asymmetric unit, and diffract to a resolution of 3.6 A. The x-ray diffraction pattern of the PSIIcc-monomer crystals exhibit less anisotropy (dependence of resolution on crystal orientation) compared with crystals of dimeric PSIIcc, and the packing of the molecules within the unit cell is different. In the monomer, 19 protein subunits, 35 chlorophylls, two pheophytins, the non-heme iron, the primary plastoquinone Q(A), two heme groups, 11 beta-carotenes, 22 lipids, seven detergent molecules, and the Mn(4)Ca cluster of the water oxidizing complex could be assigned analogous to the dimer. Based on the new structural information, the roles of lipids and protein subunits in dimer formation of PSIIcc are discussed. Due to the lack of non-crystallographic symmetry and the orientation of the membrane normal of PSIIcc perpendicular ( approximately 87 degrees ) to the crystallographic b-axis, further information about the structure of the Mn(4)Ca cluster is expected to become available from orientation-dependent spectroscopy on this new crystal form.

  2. An Intrinsically Disordered Motif Mediates Diverse Actions of Monomeric C-reactive Protein.

    Science.gov (United States)

    Li, Hai-Yun; Wang, Jing; Meng, Fan; Jia, Zhe-Kun; Su, Yang; Bai, Qi-Feng; Lv, Ling-Ling; Ma, Fu-Rong; Potempa, Lawrence A; Yan, Yong-Bin; Ji, Shang-Rong; Wu, Yi

    2016-04-15

    Most proinflammatory actions of C-reactive protein (CRP) are only expressed following dissociation of its native pentameric assembly into monomeric form (mCRP). However, little is known about what underlies the greatly enhanced activities of mCRP. Here we show that a single sequence motif, i.e. cholesterol binding sequence (CBS; a.a. 35-47), is responsible for mediating the interactions of mCRP with diverse ligands. The binding of mCRP to lipoprotein component ApoB, to complement component C1q, to extracellular matrix components fibronectin and collagen, to blood coagulation component fibrinogen, and to membrane lipid component cholesterol, are all found to be markedly inhibited by the synthetic CBS peptide but not by other CRP sequences tested. Likewise, mutating CBS in mCRP also greatly impairs these interactions. Functional experiments further reveal that CBS peptide significantly reduces the effects of mCRP on activation of endothelial cells in vitro and on acute induction of IL-6 in mice. The potency and specificity of CBS are critically determined by the N-terminal residues Cys-36, Leu-37, and His-38; while the versatility of CBS appears to originate from its intrinsically disordered conformation polymorphism. Together, these data unexpectedly identify CBS as the major recognition site of mCRP and suggest that this motif may be exploited to tune the proinflammatory actions of mCRP.

  3. Design of monomeric water-soluble β-hairpin and β-sheet peptides.

    Science.gov (United States)

    Jiménez, M Angeles

    2014-01-01

    Since the first report in 1993 (JACS 115, 5887-5888) of a peptide able to form a monomeric β-hairpin structure in aqueous solution, the design of peptides forming either β-hairpins (two-stranded antiparallel β-sheets) or three-stranded antiparallel β-sheets has become a field of growing interest and activity. These studies have yielded great insights into the principles governing the stability and folding of β-hairpins and antiparallel β-sheets. This chapter provides an overview of the reported β-hairpin/β-sheet peptides focussed on the applied design criteria, reviews briefly the factors contributing to β-hairpin/β-sheet stability, and describes a protocol for the de novo design of β-sheet-forming peptides based on them. Guidelines to select appropriate turn and strand residues and to avoid self-association are provided. The methods employed to check the success of new designed peptides are also summarized. Since NMR is the best technique to that end, NOEs and chemical shifts characteristic of β-hairpins and three-stranded antiparallel β-sheets are given.

  4. Lipoamino acid-based micelles as promising delivery vehicles for monomeric amphotericin B.

    Science.gov (United States)

    Serafim, Cláudia; Ferreira, Inês; Rijo, Patrícia; Pinheiro, Lídia; Faustino, Célia; Calado, António; Garcia-Rio, Luis

    2016-01-30

    Lipoamino acid-based micelles have been developed as delivery vehicles for the hydrophobic drug amphotericin B (AmB). The micellar solubilisation of AmB by a gemini lipoamino acid (LAA) derived from cysteine and its equimolar mixtures with the bile salts sodium cholate (NaC) and sodium deoxycholate (NaDC), as well as the aggregation sate of the drug in the micellar systems, was studied under biomimetic conditions (phosphate buffered-saline, pH 7.4) using UV-vis spectroscopy. Pure surfactant systems and equimolar mixtures were characterized by tensiometry and important parameters were determined, such as critical micelle concentration (CMC), surface tension at the CMC (γCMC), maximum surface excess concentration (Γmax), and minimum area occupied per molecule at the water/air interface (Amin). Rheological behaviour from viscosity measurements at different shear rates was also addressed. Solubilisation capacity was quantified in terms of molar solubilisation ratio (χ), micelle-water partition coefficient (KM) and Gibbs energy of solubilisation (ΔGs°). Formulations of AmB in micellar media were compared in terms of drug loading, encapsulation efficiency, aggregation state of AmB and in vitro antifungal activity against Candida albicans. The LAA-containing micellar systems solubilise AmB in its monomeric and less toxic form and exhibit in vitro antifungal activity comparable to that of the commercial formulation Fungizone.

  5. Eating chemically defended prey: alkaloid metabolism in an invasive ladybird predator of other ladybirds (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Sloggett, J J; Davis, A J

    2010-01-15

    By comparison with studies of herbivore physiological adaptation to plant allelochemicals, work on predator physiological adaptation to potentially toxic prey has been very limited. Such studies are important in understanding how evolution could shape predator diets. An interesting question is the specificity of predator adaptation to prey allelochemicals, given that many predators consume diverse prey with different chemical defences. The ladybird Harmonia axyridis, an invasive species in America, Europe and Africa, is considered a significant predatory threat to native invertebrates, particularly other aphid-eating ladybirds of which it is a strong intraguild predator. Although ladybirds possess species-specific alkaloid defences, H. axyridis exhibits high tolerance for allospecific ladybird prey alkaloids. Nonetheless, it performs poorly on species with novel alkaloids not commonly occurring within its natural range. We examined alkaloid fate in H. axyridis larvae after consumption of two other ladybird species, one containing an alkaloid historically occurring within the predator's native range (isopropyleine) and one containing a novel alkaloid that does not (adaline). Our results indicate that H. axyridis rapidly chemically modifies the alkaloid to which it has been historically exposed to render it less harmful: this probably occurs outside of the gut. The novel, more toxic alkaloid persists in the body unchanged for longer. Our results suggest metabolic alkaloid specialisation, in spite of the diversity of chemically defended prey that the predator consumes. Physiological adaptations appear to have made H. axyridis a successful predator of other ladybirds; however, limitations are imposed by its physiology when it eats prey with novel alkaloids.

  6. Monomeric malonate precursors for the MOCVD of HfO2 and ZrO2 thin films.

    Science.gov (United States)

    Pothiraja, Ramasamy; Milanov, Andrian; Parala, Harish; Winter, Manuela; Fischer, Roland A; Devi, Anjana

    2009-01-28

    New Hf and Zr malonate complexes have been synthesized by the reaction of metal amides with different malonate ligands (L = dimethyl malonate (Hdmml), diethyl malonate (Hdeml), di-tert-butyl malonate (Hdbml) and bis(trimethylsilyl) malonate (Hbsml)). Homoleptic eight-coordinated monomeric compounds of the type ML4 were obtained for Hf with all the malonate ligands employed. In contrast, for Zr only Hdmml and Hdeml yielded the eight-coordinated monomeric compounds of the type ML4, while using the bulky Hdbml and Hbsml ligands resulted into mixed alkoxo-malonato six-coordinated compounds of the type [ML2(OR)2]. Single crystal X-ray diffraction studies of all the compounds are presented and discussed, and they are found to be monomeric. The complexes are solids and in solution, they retain their monomeric nature as evidenced by NMR measurements. Compared to the classical beta-diketonate complexes, [M(acac)4] and [M(thd)4] (M = Hf, Zr; acac: acetylacetonate; thd: tetramethylheptadione), the new malonate compounds are more volatile, decompose at lower temperatures and have lower melting points. In particular, the homoleptic diethyl malonate complexes of Hf and Zr melt at temperatures as low as 62 degrees C. In addition, the compounds are very stable in air and can be sublimed quantitatively. The promising thermal properties makes these compounds interesting for metal-organic chemical vapor deposition (MOCVD). This was demonstrated by depositing HfO2 and ZrO2 thin films successfully with two representative Hf and Zr complexes.

  7. Neurodevelopmental Expression Profile of Dimeric and Monomeric Group 1 mGluRs: Relevance to Schizophrenia Pathogenesis and Treatment

    Science.gov (United States)

    Lum, Jeremy S.; Fernandez, Francesca; Matosin, Natalie; Andrews, Jessica L.; Huang, Xu-Feng; Ooi, Lezanne; Newell, Kelly A.

    2016-01-01

    Group 1 metabotropic glutamate receptors (mGluR1/mGluR5) play an integral role in neurodevelopment and are implicated in psychiatric disorders, such as schizophrenia. mGluR1 and mGluR5 are expressed as homodimers, which is important for their functionality and pharmacology. We examined the protein expression of dimeric and monomeric mGluR1α and mGluR5 in the prefrontal cortex (PFC) and hippocampus throughout development (juvenile/adolescence/adulthood) and in the perinatal phencyclidine (PCP) model of schizophrenia. Under control conditions, mGluR1α dimer expression increased between juvenile and adolescence (209–328%), while monomeric levels remained consistent. Dimeric mGluR5 was steadily expressed across all time points; monomeric mGluR5 was present in juveniles, dramatically declining at adolescence and adulthood (−97–99%). The mGluR regulators, Homer 1b/c and Norbin, significantly increased with age in the PFC and hippocampus. Perinatal PCP treatment significantly increased juvenile dimeric mGluR5 levels in the PFC and hippocampus (37–50%) but decreased hippocampal mGluR1α (−50–56%). Perinatal PCP treatment also reduced mGluR1α dimer levels in the PFC at adulthood (−31%). These results suggest that Group 1 mGluRs have distinct dimeric and monomeric neurodevelopmental patterns, which may impact their pharmacological profiles at specific ages. Perinatal PCP treatment disrupted the early expression of Group 1 mGluRs which may underlie neurodevelopmental alterations observed in this model. PMID:27721389

  8. Analysis of Isoquinoline Alkaloid Composition and Wound-Induced Variation in Nelumbo Using HPLC-MS/MS.

    Science.gov (United States)

    Deng, Xianbao; Zhu, Lingping; Fang, Ting; Vimolmangkang, Sornkanok; Yang, Dong; Ogutu, Collins; Liu, Yanling; Han, Yuepeng

    2016-02-10

    Alkaloids are the most relevant bioactive components in lotus, a traditional herb in Asia, but little is known about their qualitative and quantitative distributions. Here, we report on the alkaloid composition in various lotus organs. Lotus laminae and embryos are rich in isoquinoline alkaloids, whereas petioles and rhizomes contain trace amounts of alkaloids. Wide variation of alkaloid accumulation in lamina and embryo was observed among screened genotypes. In laminae, alkaloid accumulation increases during early developmental stages, reaches the highest level at full size stage, and then decreases slightly during senescence. Vegetative and embryogenic tissues accumulate mainly aporphine-type and bisbenzylisoquinoline-type alkaloids, respectively. Bisbenzylisoquinoline-type alkaloids may be synthesized mainly in lamina and then transported into embryo via latex through phloem translocation. In addition, mechanical wounding was shown to induce significant accumulation of specific alkaloids in lotus leaves.

  9. Pyrrolizidine alkaloid-derived DNA adducts are common toxicological biomarkers of pyrrolizidine alkaloid N-oxides.

    Science.gov (United States)

    He, Xiaobo; Xia, Qingsu; Woodling, Kellie; Lin, Ge; Fu, Peter P

    2017-10-01

    There are 660 pyrrolizidine alkaloids (PAs) and PA N-oxides present in the plants, with approximately half being possible carcinogens. We previously reported that a set of four PA-derived DNA adducts is formed in the liver of rats administered a series of hepatocarcinogenic PAs and a PA N-oxide. Based on our findings, we hypothesized that this set of DNA adducts is a common biological biomarker of PA-induced liver tumor formation. In this study, we determined that rat liver microsomal metabolism of five hepatocarcinogenic PAs (lasiocarpine, retrorsine, riddelliine, monocrotaline, and heliotrine) and their corresponding PA N-oxides produced the same set of DNA adducts. Among these compounds, lasiocarpine N-oxide, retrorsine N-oxide, monocrotaline N-oxide, and heliotrine N-oxide are for first time shown to be able to produce these DNA adducts. These results further support the role of these DNA adducts as potential common biomarkers of PA-induced liver tumor initiation. Copyright © 2017. Published by Elsevier B.V.

  10. Monomerization of viral entry inhibitor griffithsin elucidates the relationship between multivalent binding to carbohydrates and anti-HIV activity.

    Science.gov (United States)

    Moulaei, Tinoush; Shenoy, Shilpa R; Giomarelli, Barbara; Thomas, Cheryl; McMahon, James B; Dauter, Zbigniew; O'Keefe, Barry R; Wlodawer, Alexander

    2010-09-08

    Mutations were introduced to the domain-swapped homodimer of the antiviral lectin griffithsin (GRFT). Whereas several single and double mutants remained dimeric, insertion of either two or four amino acids at the dimerization interface resulted in a monomeric form of the protein (mGRFT). Monomeric character of the modified proteins was confirmed by sedimentation equilibrium ultracentrifugation and by their high resolution X-ray crystal structures, whereas their binding to carbohydrates was assessed by isothermal titration calorimetry. Cell-based antiviral activity assays utilizing different variants of mGRFT indicated that the monomeric form of the lectin had greatly reduced activity against HIV-1, suggesting that the antiviral activity of GRFT stems from crosslinking and aggregation of viral particles via multivalent interactions between GRFT and oligosaccharides present on HIV envelope glycoproteins. Atomic resolution crystal structure of a complex between mGRFT and nonamannoside revealed that a single mGRFT molecule binds to two different nonamannoside molecules through all three carbohydrate-binding sites present on the monomer.

  11. Identification of the chromophores involved in aggregation-dependent energy quenching of the monomeric photosystem II antenna protein Lhcb5.

    Science.gov (United States)

    Ballottari, Matteo; Girardon, Julien; Betterle, Nico; Morosinotto, Tomas; Bassi, Roberto

    2010-09-03

    Non-photochemical quenching (NPQ) of excess absorbed light energy is a fundamental process that regulates photosynthetic light harvesting in higher plants. Among several proposed NPQ mechanisms, aggregation-dependent quenching (ADQ) and charge transfer quenching have received the most attention. In vitro spectroscopic features of both mechanisms correlate with very similar signals detected in more intact systems and in vivo, where full NPQ can be observed. A major difference between the models is the proposed quenching site, which is predominantly the major trimeric light-harvesting complex II in ADQ and exclusively monomeric Lhcb proteins in charge transfer quenching. Here, we studied ADQ in both monomeric and trimeric Lhcb proteins, investigating the activities of each antenna subunit and their dependence on zeaxanthin, a major modulator of NPQ in vivo. We found that monomeric Lhcb proteins undergo stronger quenching than light-harvesting complex II during aggregation and that this is enhanced by binding to zeaxanthin, as occurs during NPQ in vivo. Finally, the analysis of Lhcb5 mutants showed that chlorophyll 612 and 613, in close contact with lutein bound at site L1, are important facilitators of ADQ.

  12. Induction of antibodies against epitopes inaccessible on the HIV type 1 envelope oligomer by immunization with recombinant monomeric glycoprotein 120

    DEFF Research Database (Denmark)

    Schønning, Kristian; Bolmstedt, A; Novotny, J

    1998-01-01

    An N-glycan (N306) at the base of the V3 loop of HIV-BRU gp120 is shielding a linear neutralization epitope at the tip of the V3 loop on oligomeric Env. In contrast, this epitope is readily antigenic on monomeric gp120. Immunization with recombinant monomeric HIV-BRU gp120 may thus be expected...... to elicit antibodies preferentially neutralizing mutant variants of HIV-BRU lacking the N306 glycan. Therefore, two guinea pigs were immunized with monomeric wild-type HIV-BRU gp120 possessing the N306 glycan and immune sera were tested for neutralization against target viruses HIV-BRU, -A308, and -A308T321....... HIV-A308 and HIV-A308T321 lack the N306 glycan; HIV-A308T321 contains an additional mutation at the tip of V3 rendering it resistant to MAb binding at this epitope. Both immune sera preferentially neutralized the two mutant virus variants lacking the N306 glycan, with a 10- to 20-fold increase...

  13. Induction of antibodies against epitopes inaccessible on the HIV type 1 envelope oligomer by immunization with recombinant monomeric glycoprotein 120

    DEFF Research Database (Denmark)

    Schønning, Kristian; Bolmstedt, A; Novotny, J

    1998-01-01

    An N-glycan (N306) at the base of the V3 loop of HIV-BRU gp120 is shielding a linear neutralization epitope at the tip of the V3 loop on oligomeric Env. In contrast, this epitope is readily antigenic on monomeric gp120. Immunization with recombinant monomeric HIV-BRU gp120 may thus be expected...... to elicit antibodies preferentially neutralizing mutant variants of HIV-BRU lacking the N306 glycan. Therefore, two guinea pigs were immunized with monomeric wild-type HIV-BRU gp120 possessing the N306 glycan and immune sera were tested for neutralization against target viruses HIV-BRU, -A308, and -A308T321....... HIV-A308 and HIV-A308T321 lack the N306 glycan; HIV-A308T321 contains an additional mutation at the tip of V3 rendering it resistant to MAb binding at this epitope. Both immune sera preferentially neutralized the two mutant virus variants lacking the N306 glycan, with a 10- to 20-fold increase...

  14. Monomeric and gemini surfactants as antimicrobial agents - influence on environmental and reference strains.

    Science.gov (United States)

    Koziróg, Anna; Brycki, Bogumił

    2015-01-01

    Quaternary ammonium salts (QAS) belong to surfactant commonly used both, in the household and in different branches of industry, primarily in the process of cleaning and disinfection. They have several positive features inter alia effectively limiting the development of microorganisms on many surfaces. In the present work, two compounds were used as biocides: hexamethylene-1,6-bis-(N,N-dimethyl-N-dodecylammonium bromide) that belongs to the gemini surfactant (GS), and its single analogue - dodecyl(trimethyl)ammonium bromide (DTAB). Two fold dilution method was used to determine the minimum concentration of compounds (MIC) which inhibit the growth of bacteria: Staphylococcus aureus (ATCC 6538 and an environmental strain), Pseudomonas aeruginosa (ATCC 85327 and an environmental strain), and yeast Candida albicans (ATCC 11509 and an environmental strain). The viability of cells in liquid cultures with addition of these substances at ¼ MIC, ½ MIC and MIC concentrations were also determined. The obtained results show that DTAB inhibits the growth of bacteria at the concentration of 0.126-1.010 µM/ml, and gemini surfactant is active at 0.036-0.029 µM/ml. Therefore, GS is active at more than 17-70-fold lower concentrations than its monomeric analogue. Strains isolated from natural environment are less sensitive upon testing biocides than the references strains. Both compounds at the MIC value reduced the number of cells of all strains. The use of too low concentration of biocides can limit the growth of microorganisms, but often only for a short period of time in case of special environmental strains. Later on, they can adapt to adverse environmental conditions and begin to evolve defence mechanisms.

  15. Production of transgenic cloned pigs expressing the far-red fluorescent protein monomeric Plum.

    Science.gov (United States)

    Watanabe, Masahito; Kobayashi, Mirina; Nagaya, Masaki; Matsunari, Hitomi; Nakano, Kazuaki; Maehara, Miki; Hayashida, Gota; Takayanagi, Shuko; Sakai, Rieko; Umeyama, Kazuhiro; Watanabe, Nobuyuki; Onodera, Masafumi; Nagashima, Hiroshi

    2015-01-01

    Monomeric Plum (Plum), a far-red fluorescent protein with photostability and photopermeability, is potentially suitable for in vivo imaging and detection of fluorescence in body tissues. The aim of this study was to generate transgenic cloned pigs exhibiting systemic expression of Plum using somatic cell nuclear transfer (SCNT) technology. Nuclear donor cells for SCNT were obtained by introducing a Plum-expression vector driven by a combination of the cytomegalovirus early enhancer and chicken beta-actin promoter into porcine fetal fibroblasts (PFFs). The cleavage and blastocyst formation rates of reconstructed SCNT embryos were 81.0% (34/42) and 78.6% (33/42), respectively. At 36-37 days of gestation, three fetuses systemically expressing Plum were obtained from one recipient to which 103 SCNT embryos were transferred (3/103, 2.9%). For generation of offspring expressing Plum, rejuvenated PFFs were established from one cloned fetus and used as nuclear donor cells. Four cloned offspring and one stillborn cloned offspring were produced from one recipient to which 117 SCNT embryos were transferred (5/117, 4.3%). All offspring exhibited high levels of Plum fluorescence in blood cells, such as lymphocytes, monocytes and granulocytes. In addition, the skin, heart, kidney, pancreas, liver and spleen also exhibited Plum expression. These observations demonstrated that transfer of the Plum gene did not interfere with the development of porcine SCNT embryos and resulted in the successful generation of transgenic cloned pigs that systemically expressed Plum. This is the first report of the generation and characterization of transgenic cloned pigs expressing the far-red fluorescent protein Plum.

  16. Crystal structure of a monomeric thiolase-like protein type 1 (TLP1 from Mycobacterium smegmatis.

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    Neelanjana Janardan

    Full Text Available An analysis of the Mycobacterium smegmatis genome suggests that it codes for several thiolases and thiolase-like proteins. Thiolases are an important family of enzymes that are involved in fatty acid metabolism. They occur as either dimers or tetramers. Thiolases catalyze the Claisen condensation of two acetyl-Coenzyme A molecules in the synthetic direction and the thiolytic cleavage of 3-ketoacyl-Coenzyme A molecules in the degradative direction. Some of the M. smegmatis genes have been annotated as thiolases of the poorly characterized SCP2-thiolase subfamily. The mammalian SCP2-thiolase consists of an N-terminal thiolase domain followed by an additional C-terminal domain called sterol carrier protein-2 or SCP2. The M. smegmatis protein selected in the present study, referred to here as the thiolase-like protein type 1 (MsTLP1, has been biochemically and structurally characterized. Unlike classical thiolases, MsTLP1 is a monomer in solution. Its structure has been determined at 2.7 Å resolution by the single wavelength anomalous dispersion method. The structure of the protomer confirms that the N-terminal domain has the thiolase fold. An extra C-terminal domain is indeed observed. Interestingly, it consists of six β-strands forming an anti-parallel β-barrel which is completely different from the expected SCP2-fold. Detailed sequence and structural comparisons with thiolases show that the residues known to be essential for catalysis are not conserved in MsTLP1. Consistent with this observation, activity measurements show that MsTLP1 does not catalyze the thiolase reaction. This is the first structural report of a monomeric thiolase-like protein from any organism. These studies show that MsTLP1 belongs to a new group of thiolase related proteins of unknown function.

  17. Purification and biochemical characterization of a monomeric form of papaya mosaic potexvirus coat protein.

    Science.gov (United States)

    Lecours, Katia; Tremblay, Marie-Hélène; Gagné, Marie-Eve Laliberté; Gagné, Stéphane M; Leclerc, Denis

    2006-05-01

    Papaya mosaic virus (PapMV) is a flexuous rod shape virus made of 1400 subunits that assemble around a plus sense genomic RNA. The structure determination of PapMV and of flexuous viruses in general is a major challenge for both NMR and X-ray crystallography. In this report, we present the characterization of a truncated version of the PapMV coat protein (CP) that is suitable for NMR study. The deletion of the N-terminal 26 amino acids of the PapMV CP (CP27-215) generates a monomer that can be expressed to high level and easily purified for production of an adequate NMR sample. The RNA gel shift assay showed that CP27-215 lost its ability to bind RNA in vitro, suggesting that the multimerization of the subunit is important for this function. The fusion of a 6x His tag at the C-terminus improved the solubility of the monomer and allowed its concentration to 0.2 mM. The CD spectra of the truncated and the wild-type proteins were similar, suggesting that both proteins are well ordered and have a similar secondary structure. CP27-215 was 15N labeled for NMR studies and a 2D 1H-15N-HSQC spectrum confirmed the presence of a well-ordered structure and the monomeric form of the protein. These results show that CP27-215 is amenable to a complete and exhaustive NMR study that should lead to the first three-dimensional structure determination of a flexuous rod shape virus.

  18. Production of transgenic cloned pigs expressing the far-red fluorescent protein monomeric Plum

    Science.gov (United States)

    WATANABE, Masahito; KOBAYASHI, Mirina; NAGAYA, Masaki; MATSUNARI, Hitomi; NAKANO, Kazuaki; MAEHARA, Miki; HAYASHIDA, Gota; TAKAYANAGI, Shuko; SAKAI, Rieko; UMEYAMA, Kazuhiro; WATANABE, Nobuyuki; ONODERA, Masafumi; NAGASHIMA, Hiroshi

    2015-01-01

    Monomeric Plum (Plum), a far-red fluorescent protein with photostability and photopermeability, is potentially suitable for in vivo imaging and detection of fluorescence in body tissues. The aim of this study was to generate transgenic cloned pigs exhibiting systemic expression of Plum using somatic cell nuclear transfer (SCNT) technology. Nuclear donor cells for SCNT were obtained by introducing a Plum-expression vector driven by a combination of the cytomegalovirus early enhancer and chicken beta-actin promoter into porcine fetal fibroblasts (PFFs). The cleavage and blastocyst formation rates of reconstructed SCNT embryos were 81.0% (34/42) and 78.6% (33/42), respectively. At 36–37 days of gestation, three fetuses systemically expressing Plum were obtained from one recipient to which 103 SCNT embryos were transferred (3/103, 2.9%). For generation of offspring expressing Plum, rejuvenated PFFs were established from one cloned fetus and used as nuclear donor cells. Four cloned offspring and one stillborn cloned offspring were produced from one recipient to which 117 SCNT embryos were transferred (5/117, 4.3%). All offspring exhibited high levels of Plum fluorescence in blood cells, such as lymphocytes, monocytes and granulocytes. In addition, the skin, heart, kidney, pancreas, liver and spleen also exhibited Plum expression. These observations demonstrated that transfer of the Plum gene did not interfere with the development of porcine SCNT embryos and resulted in the successful generation of transgenic cloned pigs that systemically expressed Plum. This is the first report of the generation and characterization of transgenic cloned pigs expressing the far-red fluorescent protein Plum. PMID:25739316

  19. Structural Analysis of Monomeric RNA-Dependent Polymerases: Evolutionary and Therapeutic Implications.

    Directory of Open Access Journals (Sweden)

    Rodrigo Jácome

    Full Text Available The crystal structures of monomeric RNA-dependent RNA polymerases and reverse transcriptases of more than 20 different viruses are available in the Protein Data Bank. They all share the characteristic right-hand shape of DNA- and RNA polymerases formed by the fingers, palm and thumb subdomains, and, in many cases, "fingertips" that extend from the fingers towards the thumb subdomain, giving the viral enzyme a closed right-hand appearance. Six conserved structural motifs that contain key residues for the proper functioning of the enzyme have been identified in all these RNA-dependent polymerases. These enzymes share a two divalent metal-ion mechanism of polymerization in which two conserved aspartate residues coordinate the interactions with the metal ions to catalyze the nucleotidyl transfer reaction. The recent availability of crystal structures of polymerases of the Orthomyxoviridae and Bunyaviridae families allowed us to make pairwise comparisons of the tertiary structures of polymerases belonging to the four main RNA viral groups, which has led to a phylogenetic tree in which single-stranded negative RNA viral polymerases have been included for the first time. This has also allowed us to use a homology-based structural prediction approach to develop a general three-dimensional model of the Ebola virus RNA-dependent RNA polymerase. Our model includes several of the conserved structural motifs and residues described in other viral RNA-dependent RNA polymerases that define the catalytic and highly conserved palm subdomain, as well as portions of the fingers and thumb subdomains. The results presented here help to understand the current use and apparent success of antivirals, i.e. Brincidofovir, Lamivudine and Favipiravir, originally aimed at other types of polymerases, to counteract the Ebola virus infection.

  20. Occurrence of theobromine synthase genes in purine alkaloid-free species of Camellia plants.

    Science.gov (United States)

    Ishida, Mariko; Kitao, Naoko; Mizuno, Kouichi; Tanikawa, Natsu; Kato, Misako

    2009-02-01

    Caffeine (1,3,7-trimethylxanthine) and theobromine (3,7-dimethylxanthine) are purine alkaloids that are present in high concentrations in plants of some species of Camellia. However, most members of the genus Camellia contain no purine alkaloids. Tracer experiments using [8-(14)C]adenine and [8-(14)C]theobromine showed that the purine alkaloid pathway is not fully functional in leaves of purine alkaloid-free species. In five species of purine alkaloid-free Camellia plants, sufficient evidence was obtained to show the occurrence of genes that are homologous to caffeine synthase. Recombinant enzymes derived from purine alkaloid-free species showed only theobromine synthase activity. Unlike the caffeine synthase gene, these genes were expressed more strongly in mature tissue than in young tissue.

  1. Pyrrolizidine alkaloids from seven wild-growing Senecio species in Serbia and Montenegro

    Directory of Open Access Journals (Sweden)

    BORIS M. MANDIC

    2009-01-01

    Full Text Available The genus Senecio (family Asteraceae is one of the largest in the world. It comprises about 1100 species which are the rich source of pyrrolizidine alkaloids. Plants containing pyrrolizidine alkaloids are among the most important sources of human and animal exposure to plant toxins and carcinogens. The pyrrolizidine alkaloids of seven Senecio species (S. erucifolius, S. othonnae, S. wagneri, S. subalpinus, S. carpathicus, S. paludosus and S. rupestris were studied. Fourteen alkaloids were isolated and their structures determined from spectroscopic data (1H- and 13C-NMR, IR and MS. Five of them were identified in S. erucifolius, four in S. othonnae, two in S. wagneri, four in S. subalpinus, two in S. carpathicus, three in S. paludosus and three in S. rupestris. Seven pyrrolizidine alkaloids were found for the first time in particular species. The results have chemotaxonomic importance. The cytotoxic activity and antimicrobial activity of some alkaloids were also studied.

  2. Analysis of bioactive Amaryllidaceae alkaloid profiles in Lycoris species by GC-MS.

    Science.gov (United States)

    Guo, Ying; Pigni, Natalia B; Zheng, Yuhong; de Andrade, Jean Paulo; Torras-Claveria, Laura; Borges, Warley de Souza; Viladomat, Frances; Codina, Carles; Bastida, Jaume

    2014-08-01

    The genus Lycoris, a group of Amaryllidaceae plants distributed in temperate regions of Eastern Asia, is already known for containing representative alkaloids typical of this botanical family with a wide range of biological activities (for example, lycorine and galanthamine). In the present work, the alkaloid profiles of nine species, L. albiflora, L. aurea, L. chinensis, L. haywardii, L. incarnata, L. longituba, L. radiata, L. sprengeri, and L. squamigera, and one variety (L. radiata var. pumila) have been evaluated by GC-MS. Structures belonging to the lycorine-, homolycorine-, haemanthamine-, narciclasine-, tazettine-, montanine- and galanthamine-series were identified and quantified, with galanthamine- and lycorine-type alkaloids predominating and usually showing a high relative abundance in comparison with other alkaloids of the extracts. Interestingly, L. longituba revealed itself to be a potential commercial source of bioactive alkaloids. In general terms, our results are consistent with the alkaloid profiles reported in the literature for previously studied species.

  3. Nerinine and homolycorine, amaryllidaceae alkaloids from the bulbs of Galanthus transcaucasicus Fomin

    Directory of Open Access Journals (Sweden)

    M. Babashpour-Asl

    2017-01-01

    Full Text Available Background and objectives: Many members of the Amaryllidaceae are regarded as toxic. The toxic constituents that occur in the whole family are referred to as the Amaryllidaceae alkaloids. The main aim of this study was the identification of alkaloid compounds from Galanthus transcaucasicus Fomin, a medicinal plant from Amaryllidaceae. Methods: Planar and column chromatography techniques were used for isolation of alkaloid components. GC/MS analysis was carried out for the identification of alkaloid compounds. Results: Silica gel column chromatography of the alkaloidal extract of G. transcaucasicus bulbs afforded seven fractions. Preparative thin layer chromatography of these fractions led to the isolation of compounds 1 (nerinineand 2 (homolycorine. Galantamine was not detected in any of these fractions. Conclusion: Our findings showed that G. transcaucasicus could be a new source of bioactive alkaloids for possible applications in pharmaceutical industries.

  4. Biogenetically inspired synthesis and skeletal diversification of indole alkaloids

    Science.gov (United States)

    Mizoguchi, Haruki; Oikawa, Hideaki; Oguri, Hiroki

    2014-01-01

    To access architecturally complex natural products, chemists usually devise a customized synthetic strategy for constructing a single target skeleton. In contrast, biosynthetic assembly lines often employ divergent intramolecular cyclizations of a polyunsaturated common intermediate to produce diverse arrays of scaffolds. With the aim of integrating such biogenetic strategies, we show the development of an artificial divergent assembly line generating unprecedented numbers of scaffold variations of terpenoid indole alkaloids. This approach not only allows practical access to multipotent intermediates, but also enables systematic diversification of skeletal, stereochemical and functional group properties without structural simplification of naturally occurring alkaloids. Three distinct modes of [4+2] cyclizations and two types of redox-mediated annulations provided divergent access to five skeletally distinct scaffolds involving iboga-, aspidosperma-, andranginine- and ngouniensine-type skeletons and a non-natural variant within six to nine steps from tryptamine. The efficiency of our approach was demonstrated by successful total syntheses of (±)-vincadifformine, (±)-andranginine and (-)-catharanthine.

  5. Various alkaloid profiles in decoctions of Banisteriopsis caapi.

    Science.gov (United States)

    Callaway, J C

    2005-06-01

    Twenty nine decoctions of Banisteriopsis caapi from four different sources and one specimen of B. caapi paste were analyzed for N,N-dimethyltryptamine (DMT), tetrahydroharmine (THH), harmaline and harmine. Other plants were also used in the preparation of these products, typically Psychotria viridis, which provides DMT. There were considerable variations in alkaloid profiles, both within and between sample sources. DMT was not detected in all samples. Additional THH may be formed from both harmine and harmaline during the preparation of these products. The alkaloid composition of one decoction sample did not change significantly after standing at room temperature for 80 days, but the initial acidic pH was neutralized by natural fermentation after 50 days.

  6. A Submarine Journey: The Pyrrole-Imidazole Alkaloids

    Directory of Open Access Journals (Sweden)

    Alessandra Scolaro

    2009-11-01

    Full Text Available In his most celebrated tale “The Picture of Dorian Gray”, Oscar Wilde stated that “those who go beneath the surface do so at their peril”. This sentence could be a prophetical warning for the practitioner who voluntarily challenges himself with trying to synthesize marine sponge-deriving pyrrole-imidazole alkaloids. This now nearly triple-digit membered community has been growing exponentially in the last 20 years, both in terms of new representatives and topological complexity − from simple, achiral oroidin to the breathtaking 12-ring stylissadines A and B, each possessing 16 stereocenters. While the biosynthesis and the role in the sponge economy of most of these alkaloids still lies in the realm of speculations, significant biological activities for some of them have clearly emerged. This review will account for the progress in achieving the total synthesis of the more biologically enticing members of this class of natural products.

  7. A submarine journey: the pyrrole-imidazole alkaloids.

    Science.gov (United States)

    Forte, Barbara; Malgesini, Beatrice; Piutti, Claudia; Quartieri, Francesca; Scolaro, Alessandra; Papeo, Gianluca

    2009-11-27

    In his most celebrated tale "The Picture of Dorian Gray", Oscar Wilde stated that "those who go beneath the surface do so at their peril". This sentence could be a prophetical warning for the practitioner who voluntarily challenges himself with trying to synthesize marine sponge-deriving pyrrole-imidazole alkaloids. This now nearly triple-digit membered community has been growing exponentially in the last 20 years, both in terms of new representatives and topological complexity--from simple, achiral oroidin to the breathtaking 12-ring stylissadines A and B, each possessing 16 stereocenters. While the biosynthesis and the role in the sponge economy of most of these alkaloids still lies in the realm of speculations, significant biological activities for some of them have clearly emerged. This review will account for the progress in achieving the total synthesis of the more biologically enticing members of this class of natural products.

  8. A Submarine Journey: The Pyrrole-Imidazole Alkaloids

    Science.gov (United States)

    Forte, Barbara; Malgesini, Beatrice; Piutti, Claudia; Quartieri, Francesca; Scolaro, Alessandra; Papeo, Gianluca

    2009-01-01

    In his most celebrated tale “The Picture of Dorian Gray”, Oscar Wilde stated that “those who go beneath the surface do so at their peril”. This sentence could be a prophetical warning for the practitioner who voluntarily challenges himself with trying to synthesize marine sponge-deriving pyrrole-imidazole alkaloids. This now nearly triple-digit membered community has been growing exponentially in the last 20 years, both in terms of new representatives and topological complexity – from simple, achiral oroidin to the breathtaking 12-ring stylissadines A and B, each possessing 16 stereocenters. While the biosynthesis and the role in the sponge economy of most of these alkaloids still lies in the realm of speculations, significant biological activities for some of them have clearly emerged. This review will account for the progress in achieving the total synthesis of the more biologically enticing members of this class of natural products. PMID:20098608

  9. Potent Antiplasmodial Alkaloids and Flavonoids from Dasymaschalon acuminatum

    Directory of Open Access Journals (Sweden)

    Ratchanaporn Chokchaisiri

    2015-01-01

    Full Text Available A new aporphine alkaloid, 7-epi-duguetine (1 together with one known alkaloid, dicentrinone (2, and four known flavonoids, quercetin 3,7-dimethyl ether 3′ -O- α -L-rhamnopyranosyl-(1 g 2-β-D-glucopyranoside (3, galangin 5-methyl ether (4, 5,7-dimethoxy-3-hydroxyflavone (5, and 3,5,7-trimethoxyflavone (6, were isolated from the leaves of Dasymaschalon acuminatum , a new plant species which has not been investigated phytochemically before. The structures of the isolated compounds were elucidated through extensive NMR spectroscopic analysis. All isolates were evaluated for antiplasmodial activity against Plasmodium falciparum strain K1 and 7- epi -duguetine was found to exhibit potent activity with an IC 50 of 0.385 m g/ml .

  10. Anti-leishmanial activity of alkaloidal extract from Aspidosperma ramiflorum

    Directory of Open Access Journals (Sweden)

    Izabel Cristina Piloto Ferreira

    2004-05-01

    Full Text Available Infections due to protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The drugs of choice for the treatment of leishmaniasis are the pentavalent antimonials (SbV, which present renal and cardiac toxicity. Besides, the precise chemical structure and mechanism of action of these drugs are unknown up to date. In order to find new drugs against leishmaniasis, we have been studying extracts of Brazilian trees. In the present study, we have evaluated the effectiveness of an alkaloid extract of Aspidosperma ramiflorum Muell. Arg. (Apocynaceae, against the extracellular forms promastigotes of L. (L. amazonensis and L. (V. braziliensis. The alkaloid extract of A. ramiflorum was much more effective against L. (L. amazonensis (LD50 < 47 µg/ml than L. (V. braziliensis. Based on these in vitro results against L. (L. amazonensis new studies should be made to find the compounds with anti-leishmanial activity.

  11. Separation of bisbenzylisoquinoline alkaloids by micellar electrokinetic chromatography.

    Science.gov (United States)

    Kuo, Ching-Hua; Sun, Shao-Wen

    2002-01-01

    The micellar electrokinetic chromatographic (MEKC) separation of seven bisbenzylisoquinoline alkaloids has been developed. The effects of various separating factors were studied. Optimum separation was achieved using a buffer (pH 9.2) of 20 mM sodium borate and 20 mM sodium dihydrogen phosphate buffer containing 55 mM sodium cholate; the optimum voltage and injection time were 21 kV and 0.05 min, respectively. Highest peak efficiency was obtained when the analytes were dissolved in 10 mM sodium dodecyl sulphate as sample matrix for injection. The elution order of the bisbenzylisoquinoline alkaloids was related to their lipophilicity. The resolution, run time and detection limits of the MEKC method were compared with those of an HPLC method developed previously.

  12. Synthesis and Antimicrobial Characterization of Half-Calycanthaceous Alkaloid Derivatives

    Directory of Open Access Journals (Sweden)

    Shaojun Zheng

    2016-09-01

    Full Text Available A total of 29 novel tetrahydropyrroloindol-based calycanthaceous alkaloid derivatives were synthesized from indole-3-acetonitrile in good yields. The synthesized compounds were evaluated against nine strains of bacteria and a wide range of plant pathogen fungi. Bioassay results revealed that majority of the compounds displayed similar or higher in vitro antimicrobial activities than the positive control. The biological activities also indicated that substituents at R4 and R5 significantly affect the activities. Notably, compound c4 was found to be most active among the tested calycanthaceous analogues and might be a novel potential leading compound for further development as an antifungal agent. The results could pave the way for further design and structural modification of calycanthaceous alkaloids as antimicrobial agents.

  13. [Reduced glutathione interaction with thiophosphoric derivatives of alkaloids of Chelidonium majus L. in vitro].

    Science.gov (United States)

    Glazev, A A; Nefedov, L I

    2009-01-01

    The interaction between reduced glutathione and thiophosphoric derivatives of alkaloids of greater celandine was studied by the photometric method of analysis and fluorescence spectroscopy in vitro. Results demonstrate possibility of specific interaction between reduced glutathione and thiophosphoric derivatives of alkaloids. It is possible that similar interaction of thiophosphoric derivatives of alkaloids may involve SH-groups of amino-acid residues, at the active sites of some metabolic enzymes.

  14. Taxonomic distribution of defensive alkaloids in Nearctic oribatid mites (Acari, Oribatida).

    Science.gov (United States)

    Saporito, Ralph A; Norton, Roy A; Garraffo, Martin H; Spande, Thomas F

    2015-11-01

    The opisthonotal (oil) glands of oribatid mites are the source of a wide diversity of taxon-specific defensive chemicals, and are likely the location for the more than 90 alkaloids recently identified in oribatids. Although originally recognized in temperate oribatid species, alkaloids have also been detected in related lineages of tropical oribatids. Many of these alkaloids are also present in a worldwide radiation of poison frogs, which are known to sequester these defensive chemicals from dietary arthropods, including oribatid mites. To date, most alkaloid records involve members of the superfamily Oripodoidea (Brachypylina), although few species have been examined and sampling of other taxonomic groups has been highly limited. Herein, we examined adults of more than 60 species of Nearctic oribatid mites, representing 46 genera and 33 families, for the presence of alkaloids. GC-MS analyses of whole body extracts led to the detection of 15 alkaloids, but collectively they occur only in members of the genera Scheloribates (Scheloribatidae) and Protokalumma (Parakalummidae). Most of these alkaloids have also been detected previously in the skin of poison frogs. All examined members of the oripodoid families Haplozetidae and Oribatulidae were alkaloid-free, and no mites outside the Oripodoidea contained alkaloids. Including previous studies, all sampled species of the cosmopolitan oripodoid families Scheloribatidae and Parakalummidae, and the related, mostly tropical families Mochlozetidae and Drymobatidae contain alkaloids. Our findings are consistent with a generalization that alkaloid presence is widespread, but not universal in Oripodoidea. Alkaloid presence in tropical, but not temperate members of some non-oripodoid taxa (in particular Galumnidae) deserves further study.

  15. Genotoxic Pyrrolizidine Alkaloids — Mechanisms Leading to DNA Adduct Formation and Tumorigenicity

    OpenAIRE

    2002-01-01

    Abstract: Plants that contain pyrrolizidine alkaloids are widely distributed in the world. Although pyrrolizidine alkaloids have been shown to be genotoxic and tumorigenic in experimental animals, the mechanisms of actions have not been fully understood. The results of our recent mechanistic studies suggest that pyrrolizidine alkaloids induce tumors via a genotoxic mechanism mediated by 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5Hpyrrolizine (DHP)-derived DNA adduct formation. This mechanism may ...

  16. Diversity of Pyrrolizidine Alkaloids in the Boraginaceae Structures, Distribution, and Biological Properties

    OpenAIRE

    2014-01-01

    Among the diversity of secondary metabolites which are produced by plants as means of defence against herbivores and microbes, pyrrolizidine alkaloids (PAs) are common in Boraginaceae, Asteraceae and some other plant families. Pyrrolizidine alkaloids are infamous as toxic compounds which can alkylate DNA und thus cause mutations and even cancer in herbivores and humans. Almost all genera of the family Boraginaceae synthesize and store this type of alkaloids. This review reports the available ...

  17. New bisindole alkaloids isolated from Myxomycetes Arcyria cinerea and Lycogala epidendrum.

    Science.gov (United States)

    Kamata, Kazuaki; Kiyota, Makiko; Naoe, Ayano; Nakatani, Satomi; Yamamoto, Yukinori; Hayashi, Masahiko; Komiyama, Kanki; Yamori, Takao; Ishibashi, Masami

    2005-05-01

    Two new bisindole alkaloids, named cinereapyrrole A (1) and B (2), were isolated from wild fruit bodies of Arcyria cinerea and three new bisindole alkaloids (3-5) were isolated from wild fruit bodies of Lycogala epidendrum. Seven known bisindoles (6-12) were concomitantly obtained from them. The structures of the new compounds were elucidated by spectral data. Among these bisindole alkaloids, compound 12 showed cytotoxicity against cultured tumor cell lines.

  18. Biological activity of the alkaloids of Erythroxylum coca and Erythroxylum novogranatense

    OpenAIRE

    1984-01-01

    The cultivated Erythroxylum varieties E. coca var. coca, E. coca var. ipadu, E. novogranatense var. novogranatense and E. novogranatense var. truxillense contain 18 alkaloids, identified so far, belonging to the tropanes, pyrrolidines and pyridines, with cocaine as the main alkaloid. The biological activity of the following alkaloids has been reported in the literature: cocaine, cinnamoylcocaine, benzoylecgonine, methylecgonine, pseudotropine, benzoyltropine, tropacocaine, α- and β-truxilline...

  19. Monomeric adiponectin increases cell viability in porcine aortic endothelial cells cultured in normal and high glucose conditions: Data on kinases activation

    Directory of Open Access Journals (Sweden)

    Elena Grossini

    2016-09-01

    Full Text Available We found that monomeric adiponectin was able to increase cell viability in porcine aortic endothelial cells (PAE cultured both in normal and high glucose condition. Moreover, in normal glucose condition monomeric adiponectin increased p38MAPK, Akt, ERK1/2 and eNOS phosphorylation in a dose- and time-dependent way. Also in high glucose condition monomeric adiponectin increased eNOS and above kinases phosphorylation with similar patterns but at lower extent. For interpretation of the data presented in this article, please see the research article “Monomeric adiponectin modulates nitric oxide release and calcium movements in porcine aortic endothelial cells in normal/high glucose conditions” (Grossini et al., in press [1].

  20. A monomeric methyl and hydroxypropyl methacrylate injection medium and its utility in casting blood capillaries and liver bile canaliculi for scanning electron microscopy.

    Science.gov (United States)

    Murakami, T; Itoshima, T; Hitomi, K; Ohtsuka, A; Jones, A L

    1984-06-01

    A mixture of 50-60% monomeric methyl methacrylate and 40-50% monomeric 2-hydroxypropyl methacrylate was supplemented with 1.5% benzoyl peroxide (catalyst) and 1.5% N,N-dimethylaniline (accelerator) and injected into glutaraldehyde-perfusion fixed rat hypophyseal and other endocrine organ blood vessels and biliary tracts. This injection medium rapidly polymerized at room temperature and did not require partial polymerization prior to injection. Good casts of blood vessels, including the hypophyseal capillaries, were obtained for scanning electron microscopy. The monomeric methacrylate medium possesses a great advantage over previous ones, as its fluidity enables the casting of very fine vessels such as bile canaliculi. In the case of non-fixed tissues, the monomeric methacrylate medium should be injected carefully, as it is toxic and destructive to the vessels.

  1. Acetylcholinesterase inhibitory activity of pyrrolizidine alkaloids from Echium confusum Coincy.

    Science.gov (United States)

    Benamar, Houari; Tomassini, Lamberto; Venditti, Alessandro; Marouf, Abderrazak; Bennaceur, Malika; Serafini, Mauro; Nicoletti, Marcello

    2017-06-01

    Four pyrrolizidine alkaloids, namely 7-O-angeloyllycopsamine N-oxide 1, echimidine N-oxide 2, echimidine 3 and 7-O-angeloylretronecine 4, were isolated for the first time from the whole plant ethanolic extract of Echium confusum Coincy, through bioassay-guided approach. Their structures were determined by spectroscopic means. All the isolates compounds showed moderate activities in inhibiting AChE, with IC50 0.276-0.769.

  2. Alkaloid and other chemical constituents from Psychotria stachyoides Benth

    Energy Technology Data Exchange (ETDEWEB)

    Pimenta, Antonia T.A.; Uchoa, Daniel E.A.; Silveira, Edilberto R.; Lima, Mary Anne S. [Departamento de Quimica Organica e Inorganica, Universidade Federal do Ceara, Fortaleza, CE (Brazil); Braz-Filho, Raimundo, E-mail: mary@dqoi.ufc.br [Centro de Ciencias, Universidade Estadual do Norte Fluminense and Universidade Federal Rural do Rio de Janeiro, Campos dos Goytacazes-RJ (Brazil)

    2011-09-15

    The organic extracts of leaves and roots of Psychotria stachyoides provided the new glucoside monoterpenoid indole alkaloid N-demethylcorreantoside, besides bizantionoside B, a-amyrin, alizarine methyl-ether, rubiadine, scopoletin, barbinevic acid and a mixture of b-sitosterol and stigmasterol glucosides. The structural characterization of the isolates was established based on infrared spectroscopy (IR), mass spectrometry (MS) and, particularly, 1D and 2D nuclear magnetic resonance (NMR). (author)

  3. Reviewing colchicaceae alkaloids – perspectives of evolution on medicinal chemistry

    DEFF Research Database (Denmark)

    Larsson, Sonny; Rønsted, Nina

    2014-01-01

    . In this review an approach of taking phylogenetic classification into account in evaluating colchicine and related phenethylisoquinoline alkaloids from the family Colchicaceae will be applied. Following on the trends of utilizing evolutionary reasoning in inferring mechanisms in eg. drug resistance in cancer...... and infections, this will exemplify how thinking about evolution can influence selection of plant material in drug lead discovery, and how knowledge about phylogenetic relationships may be used to evaluate predicted biosynthetic pathways...

  4. Structure, Biosynthesis, and Occurrence of Bacterial Pyrrolizidine Alkaloids.

    Science.gov (United States)

    Schimming, Olivia; Challinor, Victoria L; Tobias, Nicholas J; Adihou, Hélène; Grün, Peter; Pöschel, Laura; Richter, Christian; Schwalbe, Harald; Bode, Helge B

    2015-10-19

    Pyrrolizidine alkaloids (PAs) are widespread plant natural products with potent toxicity and bioactivity. Herein, the identification of bacterial PAs from entomopathogenic bacteria using differential analysis by 2D NMR spectroscopy (DANS) and mass spectrometry is described. Their biosynthesis was elucidated to involve a non-ribosomal peptide synthetase. The occurrence of these biosynthesis gene clusters in Gram-negative and Gram-positive bacteria indicates an important biological function in bacteria.

  5. Quantitative analysis of bioactive carbazole alkaloids in Murraya koenigii.

    Science.gov (United States)

    Joshi, Trapti; Mahar, Rohit; Singh, Sumit K; Srivastava, Piush; Shukla, Sanjeev K; Mishra, Dipak K; Bhatta, R S; Kanojiya, Sanjeev

    2015-02-01

    Carbazole alkaloids induce apoptosis in HL-60 cells through activation of the caspase-9/caspase-3 pathway and they are targeted as potential anticancer agents. Thus, the naturally occurring carbazole alkaloids become important as precursors for lead optimization in drug development. A method based on ultra performance liquid chromatography coupled with photodiode-array detection was developed using reverse phase isocratic elution with 85:15 acetonitrile and ammonium acetate buffer (5 mM). Seven samples of Murrya koenigii (L.) Spreng. from north-central India (Uttar Pradesh) were analyzed. All three targeted analytes, koenimbidine (mk1), koenimbine (mk2) and mahanimbine (mk3), were well separated within 4.0 min with linearity of the calibration curves (r2 > 0.999). The limits of detection and quantification of mk1, mk2 and mk3 were 0.7, 0.4, 0.04 μg/mL and 2.14, 1.21, 0.12 μg/mL, respectively. The natural abundance of mk1, mk2 and mk3 was 0.06-0.20, 0.04-0.69 and 0.13-0.42%, w/w, respectively, in the dried powdered leaves, whereas, the tissue specific distribution of carbazole alkaloids was observed in the order of predominance, mk1 leaf>root>fruit>stem, mk2 fruit>leaf >stem>root, and mk3 fruit>leaf>root>stem. The developed method was validated for limits of detection and quantification, repeatability, accuracy, precision and stability. This is the first report on the natural abundance of the major carbazole alkaloids in M. koenigii and the method developed can be used in HPLC/UPLC systems.

  6. Anxiolytic-like effects of erythrinian alkaloids from Erythrina suberosa

    Energy Technology Data Exchange (ETDEWEB)

    Serrano, Maria Amelia R.; Batista, Andrea N. de L.; Bolzani, Vanderlan da S.; Santos, Luciana de A. [UNESP, Araraquara, SP (Brazil). Inst. de Quimica; Nogueira, Paulo J. de C.; Nunes-de-Souza, Ricardo L. [UNESP, Araraquara, SP (Brazil). Faculdade de Ciencias Farmaceuticas; Latif, Abdul; Arfan, Mohammad [University of Peshawar, Peshawar (Pakistan). Inst. of Chemical Sciences

    2011-07-01

    Two alkaloids, erysodine (1) and erysothrine (2) were isolated from the flowers of a Pakistani medicinal plant, Erythrina suberosa. These compounds were investigated for anxiolytic properties, and the results showed significant effect, in an acute oral treatment with 1-2, which were suspended in saline (NaCl 0.9%) plus DMSO 1%, and evaluated in 122 Swiss male mice exposed to two tests of anxiety - the elevated plus-maze (EPM) and the light/dark transition model (LDTM). (author)

  7. Coumarins and alkaloids in shoot culture of Ruta graveolens L.

    Directory of Open Access Journals (Sweden)

    Halina Ekiert

    2014-01-01

    Full Text Available A shoot culture of Ruta graveolens L. (Rutaceae was maintained in the stationary liquid phase. From the cultured shoots seven compounds were isolated and identified as psoralen, bergapten, xanthotoxin, isopimpinellin (linear furanocoumarins, rutamarin (linear dihydrofuranocoumarin, kokusaginine and skimmianine (furanoquinoline alkaloids by spectral methods. The compounds are known as secondary metabolites of the intact plant, as well as its cell and tissue cultures.

  8. Widespread Chemical Detoxification of Alkaloid Venom by Formicine Ants.

    Science.gov (United States)

    LeBrun, Edward G; Diebold, Peter J; Orr, Matthew R; Gilbert, Lawrence E

    2015-10-01

    The ability to detoxify defensive compounds of competitors provides key ecological advantages that can influence community-level processes. Although common in plants and bacteria, this type of detoxification interaction is extremely rare in animals. Here, using laboratory behavioral assays and analyses of videotaped interactions in South America, we report widespread venom detoxification among ants in the subfamily Formicinae. Across both data sets, nine formicine species, representing all major clades, used a stereotyped grooming behavior to self-apply formic acid (acidopore grooming) in response to fire ant (Solenopsis invicta and S. saevissima) venom exposure. In laboratory assays, this behavior increased the survivorship of species following exposure to S. invicta venom. Species expressed the behavior when exposed to additional alkaloid venoms, including both compositionally similar piperidine venom of an additional fire ant species and the pyrrolidine/pyrroline alkaloid venom of a Monomorium species. In addition, species expressed the behavior following exposure to the uncharacterized venom of a Crematogaster species. However, species did not express acidopore grooming when confronted with protein-based ant venoms or when exposed to monoterpenoid-based venom. This pattern, combined with the specific chemistry of the reaction of formic acid with venom alkaloids, indicates that alkaloid venoms are targets of detoxification grooming. Solenopsis thief ants, and Monomorium species stand out as brood-predators of formicine ants that produce piperidine, pyrrolidine, and pyrroline venom, providing an important ecological context for the use of detoxification behavior. Detoxification behavior also represents a mechanism that can influence the order of assemblage dominance hierarchies surrounding food competition. Thus, this behavior likely influences ant-assemblages through a variety of ecological pathways.

  9. Stereoselective synthesis of enantiomerically pure nupharamine alkaloids from castoreum.

    Science.gov (United States)

    Stoye, Alexander; Quandt, Gabriele; Brunnhöfer, Björn; Kapatsina, Elissavet; Baron, Julia; Fischer, André; Weymann, Markus; Kunz, Horst

    2009-01-01

    An animalic note: The first total synthesis of the all-cis nupharamine 2, an alkaloid from beaver castoreum, is based on the stereoselective domino Mannich-Michael reaction of N-galactosylfurylaldimine to give 1 (Piv = pivaloyl), subsequent conjugate cuprate addition, and stereoselective protonation of the enolate. These reactions are all controlled by the carbohydrate. Protonation of the enolate after cleavage of the auxiliary leads to epimer 3.

  10. Mesembrine alkaloids: Review of their occurrence, chemistry, and pharmacology.

    Science.gov (United States)

    Krstenansky, John L

    2017-01-04

    Mesembrine alkaloids are considered to be the primary active constituents of the South African medicinal plant Sceletium tortuosum (L.) N.E.Br. (Aizoaceae), and it is used as the dried or fermented aerial material from the plant, which is known as kanna (aka, channa, kougoed). Traditional regional use ranged from relieving thirst, mild analgesia, and alteration of mood. Current interest has focused primarily on the antidepressant action of preparations based on the plant and commercialization is expanding the recognition and availability of these preparations. Searches for the keywords "Sceletium or mesembrine" were performed in "PubMed-NCBI", "Chemical Abstracts SciFinder" and "Thomson Reuters Web of Science" databases in addition to the inclusion of references cited within prior reviews and scientific reports. Additionally the "SciFinder" database was searched using 3a-phenyl-cis-octahydroindole in the SciFinder Substructure Module (SSM). Plant taxonomy was validated by the database "The Plant List". This review focuses on the chemistry, analysis, and pharmacology of the mesembrine alkaloids. Despite a long history of medicinal used and research investigation, there has been a renewed interest in the pharmacological properties of the mesembrine alkaloids and much of the pharmacology has only recently been published. The two major active alkaloids mesembrine and mesembrenone are still in the process of being more fully characterized pharmacologically. They are serotonin reuptake inhibitors, which provides a rationale for the plant's traditional use as an antidepressant, but other actions are beginning to appear in the literature. Additionally, mesembrenone has reasonably potent PDE4 inhibitory activity. This review intends to provide an overview of the available literature, summarize the current findings, and put them in perspective with earlier studies and reviews. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  11. Antimalarial diterpene alkaloids from the seeds of Caesalpinia minax.

    Science.gov (United States)

    Ma, Guoxu; Sun, Zhaocui; Sun, Zhonghao; Yuan, Jingquan; Wei, Hua; Yang, Junshan; Wu, Haifeng; Xu, Xudong

    2014-06-01

    Two new diterpene alkaloids, caesalminines A (1) and B (2), possessing a tetracyclic cassane-type furanoditerpenoid skeleton with γ-lactam ring, were isolated from the seeds of Caesalpinia minax. Their structures were determined by different spectroscopic methods and ECD calculation. The plausible biosynthetic pathway of caesalminines A and B was proposed. The anti-malarial activity of compounds 1 and 2 is presented with IC50 values of 0.42 and 0.79 μM, respectively.

  12. Alkaloids and acetogenins in Annonaceae development: biological considerations

    Directory of Open Access Journals (Sweden)

    Alma Rosa González-Esquinca

    2014-01-01

    Full Text Available Chemical studies of the plant family Annonaceae have intensified in the last several decades due to the discovery of annonaceous molecules with medicinal potential (e.g., benzylisoquinoline alkaloids and acetogenins. Approximately 500 alkaloids have been identified in 138 Annonaceae species in 43 genera. In addition, until 2004, 593 annonaceous acetogenins (ACGs had been identified, from 51 species in 13 genera.This suggests that plants from this family allocate important resources to the biosynthesis of these compounds. Despite the diversity of these molecules, their biological roles, including their physiological and/or ecological functions, are not well understood. In this study, it was provided new data describing the variety and distribution of certain alkaloids and ACGs in annonaceous plants in distinct stages of development. The potential relationships among some of these compounds and the seasonally climatic changes occurring in the plant habitat are also discussed. These data will improve our understanding of the secondary metabolism of these pharmacologically important molecules and their expression patterns during development, which will help to determine the optimal growth conditions and harvest times for their production.

  13. Phytotoxicity Assessment of Certain Phytochemical Products Containing Pyrrolizidine Alkaloids

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    Cristina Șeremet Oana

    2013-10-01

    Full Text Available Introduction: Tussilago farfara (coltsfoot, Petasites hybridus (common butterbur, Senecio vernalis (eastern groundsel and Symphytum officinale (comfrey are species traditionally used in phytotherapy that besides the therapeutic compounds contain toxic pyrrolizidine alkaloids (PAs. The aim of the paper is to determine the total PAs content and the phytotoxicity of the above species. Material and methods: The quantitative determination of pyrrolizidine alkaloids is based on the stoichiometric reaction of protonated alkaloids with methyl orange. In acidic conditions the dye is released from the complex and its color is assessed spectrophotometrically using a linear regression curve of senecionine as a standard. The phytotoxicity was assessed by Triticum bioassay that studies the effect of the extracts (0.001-5.00%, w/v upon root elongation (inhibitory concentration - IC50 and on the karyokinetic film. Results: The highest amount of total PAs was found in Senecio vernalis (654.8 ± 35.96 μg/g dry plant and the lowest in Petasites hybridus. The lowest IC50 was found for Tussilago farfara followed by Petasites hybridus, Senecio vernalis, and Symphytum officinale. The results were supported by microscopic examination. Conclusions: The results of the spectrophotometric assay are consistent with the ones found in the literature. All extracts inhibited the elongation of the main root of wheat caryopses, however, no correlation between phytotoxicity and the PAs concentration could be emphasized

  14. Cactus alkaloids. XXXVI. Mescaline and related compounds from Trichocereus peruvianus.

    Science.gov (United States)

    Pardanani, J H; McLaughlin, J L; Kondrat, R W; Cooks, R G

    1977-01-01

    Agurell has previously detected (tlc, glc-ms) tyramine, 3-methoxytyramine, and two unknown alkaloids in the Peruvian cactus, Trichocereus peruvianus Br. and R. The presence of mescaline in other similar Trichocereus species prompted us to reinvestigate this species, which is commercially available in the United States. The nonphenolic alkaloid extracts yielded an abundance of crystalline mescaline hydrochloride (0.82% yield) and a trace of 3,4-dimethoxyphenethylamine (tlc-ms). Crystalline tyramine hydrochloride, 3-methoxytyramine hydrochloride, and 3,5 dimethoxy-4-hydroxphenethylamine hydrochloride were isolated from the phenolic alkaloid extracts; the last compound has not been previously crystallized from nature, although it is the immediate biosynthetic precursor of mescaline. Crystalline 2-chloromescaline hydrochloride was isolated drom the nonphenolic extracts; but, as determined by mass-analyzed ion kinetic energy spectrometry, this new compound is an extraction artifact. Both 2-chloromescaline and 2.6-dichloromescaline hydrochlorides were prepared synthetically from mescaline. This cactus species has a mescaline content equal or superior to peyote and should be legally controlled as an item of drug abuse.

  15. Distribution of opiate alkaloids in brain tissue of experimental animals.

    Science.gov (United States)

    Djurendic-Brenesel, Maja; Pilija, Vladimir; Mimica-Dukic, Neda; Budakov, Branislav; Cvjeticanin, Stanko

    2012-12-01

    The present study examined regional distribution of opiate alkaloids from seized heroin in brain regions of experimental animals in order to select parts with the highest content of opiates. Their analysis should contribute to resolve causes of death due to heroin intake. The tests were performed at different time periods (5, 15, 45 and 120 min) after male and female Wistar rats were treated with seized heroin. Opiate alkaloids (codeine, morphine, acetylcodeine, 6-acetylmorphine and 3,6-diacetylmorphine) were quantitatively determined in brain regions known for their high concentration of µ-opiate receptors: cortex, brainstem, amygdala and basal ganglia, by using gas chromatography-mass spectrometry (GC-MS). The highest content of opiate alkaloids in the brain tissue of female animals was found 15 min and in male animals 45 min after treatment. The highest content of opiates was determined in the basal ganglia of the animals of both genders, indicating that this part of brain tissue presents a reliable sample for identifying and assessing contents of opiates after heroin intake.

  16. The Alkaloid Alstonine: A Review of Its Pharmacological Properties

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    E. Elisabetsky

    2006-01-01

    Full Text Available Indole compounds, related to the metabolism of tryptophan, constitute an extensive family, and are found in bacteria, plants and animals. Indolic compounds possess significant and complex physiological roles, and especially indole alkaloids have historically constituted a class of major importance in the development of new plant derived drugs. The indole alkaloid alstonine has been identified as the major component of a plant-based remedy, used in Nigeria to treat mental illnesses by traditional psychiatrists. Although it is certainly difficult to compare the very concept of mental disorders in different cultures, the traditional use of alstonine is remarkably compatible with its profile in experimental animals. Even though alstonine in mice models shows a psychopharmacological profile closer to the newer atypical antipsychotic agents, it also shows important differences and what seems to be an exclusive mechanism of action, not entirely clarified at this point. Considering the seemingly unique mode of action of alstonine and that its traditional use can be viewed as indicative of bioavailability and safety, this review focuses on the effects of alstonine in the central nervous system, particularly on its unique profile as an antipsychotic agent. We suggest that a thorough understanding of traditional medical concepts of health and disease in general and traditional medical practices in particular, can lead to true innovation in paradigms of drug action and development. Overall, the study of this unique indole alkaloid may be considered as another example of the richness of medicinal plants and traditional medical systems in the discovery of new prototypic drugs.

  17. Metabolic engineering for the production of plant isoquinoline alkaloids.

    Science.gov (United States)

    Diamond, Andrew; Desgagné-Penix, Isabel

    2016-06-01

    Several plant isoquinoline alkaloids (PIAs) possess powerful pharmaceutical and biotechnological properties. Thus, PIA metabolism and its fascinating molecules, including morphine, colchicine and galanthamine, have attracted the attention of both the industry and researchers involved in plant science, biochemistry, chemical bioengineering and medicine. Currently, access and availability of high-value PIAs [commercialized (e.g. galanthamine) or not (e.g. narciclasine)] is limited by low concentration in nature, lack of cultivation or geographic access, seasonal production and risk of overharvesting wild plant species. Nevertheless, most commercial PIAs are still extracted from plant sources. Efforts to improve the production of PIA have largely been impaired by the lack of knowledge on PIA metabolism. With the development and integration of next-generation sequencing technologies, high-throughput proteomics and metabolomics analyses and bioinformatics, systems biology was used to unravel metabolic pathways allowing the use of metabolic engineering and synthetic biology approaches to increase production of valuable PIAs. Metabolic engineering provides opportunity to overcome issues related to restricted availability, diversification and productivity of plant alkaloids. Engineered plant, plant cells and microbial cell cultures can act as biofactories by offering their metabolic machinery for the purpose of optimizing the conditions and increasing the productivity of a specific alkaloid. In this article, is presented an update on the production of PIA in engineered plant, plant cell cultures and heterologous micro-organisms.

  18. In vitro production of adaline and coccinelline, two defensive alkaloids from ladybird beetles (Coleoptera: Coccinellidae).

    Science.gov (United States)

    Laurent, Pascal; Braekman, Jean-Claude; Daloze, Désiré; Pasteels, Jacques M

    2002-09-01

    In vitro experiments using [1-(14)C] and [2-(14)C]acetate were devised to study the biosynthesis of the defensive coccinellid alkaloids adaline and coccinelline in Adalia 2-punctata and Coccinella 7-punctata, respectively. The labelled alkaloids obtained in these experiments had a specific activity about ten times higher than that of the samples obtained in feeding experiments. This in vitro assay has enabled us to demonstrate that these two alkaloids are most likely biosynthesised through a fatty acid rather than a polyketide pathway, that glutamine is the preferred source of the nitrogen atom and that alkaloid biosynthesis takes place in the insect fat body.

  19. Variation and evolution of alkaloid complex in yellow lupine (Lupinus luteus L. during domestication

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    Wiktor Święcicki

    2013-12-01

    Full Text Available A colection of 178 primitive and cultivated forms of Lupinus luteus was analysed with respect to composition and level of alkaloids in seeds. A considerable quantitative and qualitative variation in alkaloids was found in the analysed forms. All analysed primitive forms, not cultivated in Central Europe, contained gramine and lupinine; the majority had sparteine as well. Contrary to the common opinion, yellow lupine has three basic alkaloids, i.e. gramine, lupinine and sparteine. Moreover, a large number of primitive forms showed traces of unidentified alkaline compounds with alkaloid characteristics. It appears that in the course of introduction of yellow lupine to central Europe, the composition and level of its alkaloids have been gradually changing. Their reproduction and natural selection remarkably decreased the number of forms containing gramine as well as the total level of alkaloids in seeds. Cross breeding and screening for low alkaloid bearing forms significantly decreased the total level of gramine as well as the number of forms containing gramine and almost entirely eliminated traces of unidentified alkaloids. One new form was found to have sparteine and only a little of lupinine (total level of alkaloids 0,04%.

  20. Recent Advances on the Total Syntheses of Communesin Alkaloids and Perophoramidine.

    Science.gov (United States)

    Trost, Barry M; Osipov, Maksim

    2015-11-09

    The communesin alkaloids are a diverse family of Penicillium-derived alkaloids. Their caged-polycyclic structure and intriguing biological profiles have made these natural products attractive targets for total synthesis. Similarly, the ascidian-derived alkaloid, perophoramidine, is structurally related to the communesins and has also become a popular target for total synthesis. This review serves to summarize the many elegant approaches that have been developed to access the communesin alkaloids and perophoramidine. Likewise, strategies to access the communesin ring system are reviewed.

  1. Diversity of Pyrrolizidine Alkaloids in the Boraginaceae Structures, Distribution, and Biological Properties

    Directory of Open Access Journals (Sweden)

    Assem El-Shazly

    2014-04-01

    Full Text Available Among the diversity of secondary metabolites which are produced by plants as means of defence against herbivores and microbes, pyrrolizidine alkaloids (PAs are common in Boraginaceae, Asteraceae and some other plant families. Pyrrolizidine alkaloids are infamous as toxic compounds which can alkylate DNA und thus cause mutations and even cancer in herbivores and humans. Almost all genera of the family Boraginaceae synthesize and store this type of alkaloids. This review reports the available information on the present status (literature up to early 2014 of the pyrrolizidine alkaloids in the Boraginaceae and summarizes the topics structure, distribution, chemistry, chemotaxonomic significance, and biological properties.

  2. Two new cytotoxic furoquinoline alkaloids isolated from Aegle marmelos (Linn.) Correa

    DEFF Research Database (Denmark)

    Mohammed, Magdy M D; Ibrahim, Nabaweya A.; El-Sakhawy, Fatma S.

    2016-01-01

    Two new cytotoxic furoquinoline alkaloids were isolated from the leaves of Aegle marmelos (Linn.) Correa; one from the total alkaloidal fraction (acid/base shake-out method) of the CHCl3 extract and identified as 7,8-dihydroxy-4-hydrofuroquinoline and named trivially as Aegelbine-A. The other new...... alkaloid isolated from the pet. ether extract and identified as 4-hydro-7-hydroxy-8-prenyloxyfuroquinoline and named trivially as Aegelbine-B, together with a known alkaloid; aegeline and a known phenolic acid; ρ-hydroxybenzoic acid. The structures of all the isolated compounds were established based on 1D...

  3. Naturally occurring bioactive Cyclobutane-containing (CBC) alkaloids in fungi, fungal endophytes, and plants.

    Science.gov (United States)

    Dembitsky, Valery M

    2014-10-15

    This article focuses on the occurrence and biological activities of cyclobutane-containing (CBC) alkaloids obtained from fungi, fungal endophytes, and plants. Naturally occurring CBC alkaloids are of particular interest because many of these compounds display important biological activities and possess antitumour, antibacterial, antimicrobial, antifungal, and immunosuppressive properties. Therefore, these compounds are of great interest in the fields of medicine, pharmacology, medicinal chemistry, and the pharmaceutical industry. Fermentation and production of CBC alkaloids by fungi and/or fungal endophytes is also discussed. This review presents the structures and describes the activities of 98 CBC alkaloids.

  4. Crystal structure of indoline alkaloids kopsinilam, kopsinine, and the salts of the latter

    DEFF Research Database (Denmark)

    Adizov, Sh. M.; Tashkhodzhaev, B.; Kunafiev, R. Zh.

    2016-01-01

    N1 in the bases and the salts. Tetrahedral hybridization of the atom N1 in indoline alkaloids favors the formation of their double salts, what is unlikely for indole and indolinine alkaloids. In the halogen double salts there is an intramolecular Н bond between one of the protons of the NH2 group......Indoline alkaloids kopsinilam and kopsinine extracted from the plant Vinca erecta have been studied by X-ray crystallography; mono and double salts of the latter alkaloid also have been examined. Experimentally determined positions of Н atoms suggest sp3 hybridization of the indoline nitrogen atom...

  5. Integration of Transcriptome and Proteome Reveals the Alkaloids Biosynthesis in Macleaya cordata and Macleaya microcarpa

    Institute of Scientific and Technical Information of China (English)

    Yisong Liu; Wei Liu; Xiubing Liu; Peng Huang; Pengcheng Zhu; Pi Cheng; Jing Zeng

    2012-01-01

    The Macleaya spp.,including Macleaya cordata and Macleaya microcarpa,are traditional anti-virus,inflammation eliminating,and insecticide herb medicines for their isoquinoline alkaloids.The studies of their alkaloids biosyntheses are urgent for better application.To further characterize their alkaloids biosyntheses,we elaborately designed the transcriptome,proteome and metabolism profiling for 10 samples of both species to explore their alkaloids biosyntheses.From the transcriptome data,we obtained 69367 and 78255 unigenes for M.cordata and M.microcarpa,which two thirds of them were similar to sequences in public databases.By metabolism profiling,we observed reverse patterns in different organs of two species for alkaloids sanguinarine,chelerythrine,protopine,and allocryptopine.Thus,the expression of enzymes in alkaloid biosynthesis pathways and the differential gene expression for multiple interesting comparisons were analyzed.We identified more than 1000 proteins and hundreds of differentially expressed proteins from iTRAQ proteome data.Furthermore,the ultrastructure of laticifers by SEM proved the alkaloids accumulation in the mature roots.This study suggests strongly that root maybe the organ for major alkaloids biosynthesis.Except for biosynthesis,the alkaloids storage and transport were also important for their accumulation.This work provided the first genome scale analysis for Macleaya spp.and shed light on researches for non-model plants by integrating different high-throughput technologies.

  6. [Relativity among starch quantity, polysaccharides content and total alkaloid content of Dendrobium loddigesii].

    Science.gov (United States)

    Zhu, Hua; Teng, Jianbei; Cai, Yi; Liang, Jie; Zhu, Yilin; Wei, Tao

    2011-12-01

    To find out the relativity among starch quantity, polysaccharides content and total alkaloid content of Dendrobium loddigesii. Microscopy-counting process was applied to starch quantity statistics, sulfuric acid-anthrone colorimetry was used to assay polysaccharides content and bromocresol green colorimetry was used to assay alkaloid content. Pearson product moment correlation analysis, Kendall's rank correlation analysis and Spearman's concordance coefficient analysis were applied to study their relativity. Extremely significant positive correlation was found between starch quantity and polysaccharides content, and significant negative correlation between alkaloid content and starch quantity was discovered, as well was between alkaloid content and polysaccharides content.

  7. Identification and developmental expression profiling of putative alkaloid biosynthetic genes in Corydalis yanhusuo bulbs.

    Science.gov (United States)

    Liao, Dengqun; Wang, Pengfei; Jia, Chan; Sun, Peng; Qi, Jianjun; Zhou, Lili; Li, Xian'en

    2016-01-18

    Alkaloids in bulbs of Corydalis (C.) yanhusuo are the major pharmacologically active compounds in treatment of blood vessel diseases, tumors and various pains. However, due to the absence of gene sequences in C. yanhusuo, the genes involved in alkaloid biosynthesis and their expression during bulb development remain unknown. We therefore established the first transcriptome database of C. yanhusuo via Illumina mRNA-Sequencing of a RNA composite sample collected at Bulb initiation (Day 0), early enlargement (Day 10) and maturation (Day 30). 25,013,630 clean 90 bp paired-end reads were de novo assembled into 47,081 unigenes with an average length of 489 bp, among which 30,868 unigenes (65.56%) were annotated in four protein databases. Of 526 putative unigenes involved in biosynthesis o f various alkaloids, 187 were identified as the candidate genes involved in the biosynthesis of benzylisoquinoline alkaloids (BIAs), the only alkaloid type reported in C. yanhusuo untill now. BIAs biosynthetic genes were highly upregulated in the overall pathway during bulb development. Identification of alkaloid biosynthetic genes in C. yanhusuo provide insights on pathways and molecular regulation of alkaloid biosynthesis, to initiate metabolic engineering in order to improve the yield of interesting alkaloids and to identify potentially new alkaloids predicted from the transcriptomic information.

  8. Alkaloid variation in New Zealand kōwhai, Sophora species.

    Science.gov (United States)

    McDougal, Owen M; Heenan, Peter B; Jaksons, Peter; Sansom, Catherine E; Smallfield, Bruce M; Perry, Nigel B; van Klink, John W

    2015-10-01

    Alkaloid contents of leaf and seed samples of eight species of Sophora native to New Zealand, plus Sophora cassioides from Chile are reported. Fifty-six leaf and forty-two seed samples were analysed for alkaloid content by proton nuclear magnetic resonance spectroscopy, which showed major alkaloids as cytisine, N-methyl cytisine and matrine. GC analyses quantified these and identified further alkaloid components. The alkaloids identified were cytisine, sparteine, and matrine-types common to Sophora from other regions of the world. Cytisine, N-methyl cytisine, and matrine were generally the most abundant alkaloids across all species with seeds containing the highest concentrations of alkaloids. However, there was no clear taxonomic grouping based on alkaloid composition. A quantitative analysis of various parts of two Sophora microphylla trees showed that the seeds were the richest source of alkaloids (total 0.4-0.5% DM), followed by leaf and twig (0.1-0.3%) and then bark (0.04-0.06%), with only low amounts (<0.02%) found in the roots. This study represents the most comprehensive phytochemical investigation of New Zealand Sophora species to date and presents data for three species of Sophora for which no prior chemistry has been reported.

  9. New Alkaloids and α-Glucosidase Inhibitory Flavonoids from Ficus hispida.

    Science.gov (United States)

    Shi, Zheng-Feng; Lei, Chun; Yu, Bang-Wei; Wang, He-Yao; Hou, Ai-Jun

    2016-04-01

    Two new pyrrolidine alkaloids, ficushispimines A (1) and B (2), a new ω-(dimethylamino)caprophenone alkaloid, ficushispimine C (3), and a new indolizidine alkaloid, ficushispidine (4), together with the known alkaloid 5 and 11 known isoprenylated flavonoids 6 - 16, were isolated from the twigs of Ficus hispida. Their structures were elucidated by spectroscopic methods. Isoderrone (8), 3'-(3-methylbut-2-en-1-yl)biochanin A (11), myrsininone A (12), ficusin A (13), and 4',5,7-trihydroxy-6-[(1R*,6R*)-3-methyl-6-(1-methylethenyl)cyclohex-2-en-1-yl]isoflavone (14) showed inhibitory effects on α-glucosidase in vitro.

  10. Elemental step thermodynamics of various analogues of indazolium alkaloids to obtaining hydride in acetonitrile.

    Science.gov (United States)

    Lei, Nan-Ping; Fu, Yan-Hua; Zhu, Xiao-Qing

    2015-12-21

    A series of analogues of indazolium alkaloids were designed and synthesized. The thermodynamic driving forces of the 6 elemental steps for the analogues of indazolium alkaloids to obtain hydride in acetonitrile were determined using an isothermal titration calorimeter (ITC) and electrochemical methods, respectively. The effects of molecular structure and substituents on the thermodynamic driving forces of the 6 steps were examined. Meanwhile, the oxidation mechanism of NADH coenzyme by indazolium alkaloids was examined using the chemical mimic method. The result shows that the oxidation of NADH coenzyme by indazolium alkaloids in vivo takes place by one-step concerted hydride transfer mechanism.

  11. Single Enzyme Studies Reveal the Existence of Discrete Functional States for Monomeric Enzymes and How They Are “Selected” upon Allosteric Regulation

    DEFF Research Database (Denmark)

    Hatzakis, Nikos S.; Wei, Li; Jørgensen, Sune Klamer

    2012-01-01

    allosteric regulation of monomeric enzymes is poorly understood. Here we monitored for the first time allosteric regulation of enzymatic activity at the single molecule level. We measured single stochastic catalytic turnovers of a monomeric metabolic enzyme (Thermomyces lanuginosus Lipase) while titrating...... its proximity to a lipid membrane that acts as an allosteric effector. The single molecule measurements revealed the existence of discrete binary functional states that could not be identified in macroscopic measurements due to ensemble averaging. The discrete functional states correlate...

  12. CRINUM; AN ENDLESS SOURCE OF BIOACTIVE PRINCIPLES: A REVIEW, PART II. CRINUM ALKALOIDS: CRININE-TYPE ALKALOIDS

    Directory of Open Access Journals (Sweden)

    John Refaat et al

    2012-09-01

    Full Text Available Crinum is a genus of about 130 species belonging to family Amaryllidaceae with wide geographical distribution throughout the tropics, subtropics and warm temperate regions of the world. These plants are not only showy ornamentals but they possess significant folkloric and commercial reputation as well. Long ago, Crinums have been subjected to extensive chemical, cytological and pharmacological investigations. Phytochemical investigations have resulted in isolation of several diverse classes of phytocompounds and have been focused predominantly on alkaloids. The present part of our review work about the phytochemical, biological and toxicological studies on Crinums summarizes crinine-type alkaloids isolated up to now as well as their structural and stereochemical differences, in addition to their distribution in different Crinum species.

  13. Reaction of dehydropyrrolizidine alkaloids with valine and hemoglobin.

    Science.gov (United States)

    Zhao, Yuewei; Wang, Shuguang; Xia, Qingsu; Gamboa da Costa, Gonçalo; Doerge, Daniel R; Cai, Lining; Fu, Peter P

    2014-10-20

    Pyrrolizidine alkaloid-containing plants are probably the most common poisonous plants affecting livestock, wildlife, and humans. Pyrrolizidine alkaloids exert toxicity through metabolism to dehydropyrrolizidine alkaloids that bind to cellular protein and DNA, leading to hepatotoxicity, genotoxicity, and tumorigenicity. To date, it is not clear how dehydropyrrolizidine alkaloids bind to cellular constituents, including amino acids and proteins, resulting in toxicity. Metabolism of carcinogenic monocrotaline, riddelliine, and heliotrine produces dehydromonocrotaline, dehyroriddelliine, and dehydroheliotrine, respectively, as primary reactive metabolites. In this study, we report that reaction of dehydromonocrotaline with valine generated four highly unstable 6,7-dihydro-7-hydroxy-1-hydroxymethyl-5H-pyrrolizine (DHP)-derived valine (DHP-valine) adducts. For structural elucidation, DHP-valine adducts were derivatized with phenyl isothiocyanate (PITC) to DHP-valine-PITC products. After HPLC separation, their structures were characterized by mass spectrometry, UV-visible spectrophotometry, (1)H NMR, and (1)H-(1)H COSY NMR spectral analysis. Two DHP-valine-PITC adducts, designated as DHP-valine-PITC-1 and DHP-valine-PITC-3, had the amino group of valine linked to the C7 position of the necine base, and the other two DHP-valine-PITC products, DHP-valine-PITC-2 and DHP-valine-PITC-4, linked to the C9 position of the necine base. DHP-valine-PITC-1 was interconvertible with DHP-valine-PITC-3, and DHP-valine-PITC-2 was interconvertible with DHP-valine-PITC-4. Reaction of dehydroriddelliine and dehydroheliotrine with valine provided similar results. However, reaction of valine and dehydroretronecine (DHR) under similar experimental conditions did not produce DHP-valine adducts. Reaction of dehydromonocrotaline with rat hemoglobin followed by derivatization with PITC also generated the same four DHP-valine-PITC adducts. This represents the first full structural elucidation of

  14. Total allowable concentrations of monomeric inorganic aluminum and hydrated aluminum silicates in drinking water.

    Science.gov (United States)

    Willhite, Calvin C; Ball, Gwendolyn L; McLellan, Clifton J

    2012-05-01

    Maximum contaminant levels are used to control potential health hazards posed by chemicals in drinking water, but no primary national or international limits for aluminum (Al) have been adopted. Given the differences in toxicological profiles, the present evaluation derives total allowable concentrations for certain water-soluble inorganic Al compounds (including chloride, hydroxide, oxide, phosphate and sulfate) and for the hydrated Al silicates (including attapulgite, bentonite/montmorillonite, illite, kaolinite) in drinking water. The chemistry, toxicology and clinical experience with Al materials are extensive and depend upon the particular physical and chemical form. In general, the water solubility of the monomeric Al materials depends on pH and their water solubility and gastrointestinal bioavailability are much greater than that of the hydrated Al silicates. Other than Al-containing antacids and buffered aspirin, food is the primary source of Al exposure for most healthy people. Systemic uptake of Al after ingestion of the monomeric salts is somewhat greater from drinking water (0.28%) than from food (0.1%). Once absorbed, Al accumulates in bone, brain, liver and kidney, with bone as the major site for Al deposition in humans. Oral Al hydroxide is used routinely to bind phosphate salts in the gut to control hyperphosphatemia in people with compromised renal function. Signs of chronic Al toxicity in the musculoskeletal system include a vitamin D-resistant osteomalacia (deranged membranous bone formation characterized by accumulation of the osteoid matrix and reduced mineralization, reduced numbers of osteoblasts and osteoclasts, decreased lamellar and osteoid bands with elevated Al concentrations) presenting as bone pain and proximal myopathy. Aluminum-induced bone disease can progress to stress fractures of the ribs, femur, vertebrae, humerus and metatarsals. Serum Al ≥100 µg/L has a 75-88% positive predictive value for Al bone disease. Chronic Al

  15. Identification of diterpene alkaloids from Aconitum napellus subsp. firmum and GIRK channel activities of some Aconitum alkaloids.

    Science.gov (United States)

    Kiss, Tivadar; Orvos, Péter; Bánsághi, Száva; Forgo, Peter; Jedlinszki, Nikoletta; Tálosi, László; Hohmann, Judit; Csupor, Dezső

    2013-10-01

    Diterpene alkaloids neoline (1), napelline (2), isotalatizidine (3), karakoline (4), senbusine A (5), senbusine C (6), aconitine (7) and taurenine (8) were identified from Aconitum napellus L. subsp. firmum, four (2-4, 6) of which are reported for the first time from this plant. The structures were determined by means of LC-MS, 1D and 2D NMR spectroscopy, including (1)H-(1)H COSY, NOESY, HSQC and HMBC experiments. Electrophysiological effects of the isolated compounds, together with nine diterpene alkaloids previously obtained from Aconitum toxicum and Consolida orientalis were investigated on stable transfected HEK-hERG (Kv11.1) and HEK-GIRK1/4 (Kir3.1 and Kir3.4) cell lines using automated patch clamp equipment. Significant blocking activity on GIRK channel was exerted by aconitine (7) (45% at 10 μM), but no blocking activities of the other investigated compounds were detected. The tested compounds were inactive on hERG channel in the tested concentration. The comparison of the previously reported metabolites of A. napellus subsp. firmum and compounds identified in our experiment reveals substantial variability of the alkaloid profile of this taxon.

  16. Use of the quartz crystal microbalance to determine the monomeric friction coefficient of polyimides

    Science.gov (United States)

    Bechtold, Mary M.

    1995-01-01

    When a thin film of polymer is coated on to a quartz crystal microbalance (QCM), the QCM can be used to detect the rate of increase in weight of the polymer film as the volatile penetrant diffuses into the polymer. From this rate information the diffusion coefficient of the penetrant into the polymer can be computed. Calculations requiring this diffusion coefficient lead to values which approximate the monomeric friction coefficient of the polymer. This project has been concerned with the trial of crystal oscillating circuits suitable for driving polymer coated crystals in an atmosphere of penetrant. For these studies done at room temperature, natural rubber was used as an easily applied polymer that is readily penetrated by toluene vapors, qualities anticipated with polyimides when they are tested at T(g) in the presence of toluene. Three quartz crystal oscillator circuits were tested. The simplest circuit used +/- 5 volt dc and had a transistor to transistor logic (TTL) inverter chip that provides a 180 deg phase shift via a feed back loop. This oscillator circuit was stable but would not drive the crystal when the crystal was coated with polymer and subjected to toluene vapors. Removal of a variable resistor from this circuit increased stability but did not otherwise increase performance. Another driver circuit tested contained a two stage differential input, differential output, wide band video amplifier and also contain a feed back loop. The circuit voltage could not be varied and operated at +/- 5 volts dc; this circuit was also stable but failed to oscillate the polymer coated crystal in an atmosphere saturated with toluene vapors. The third oscillator circuit was of similar construction and relied on the same video amplifier but allowed operation with variable voltage. This circuit would drive the crystal when the crystal was submerged in liquid toluene and when the crystal was coated with polymer and immersed in toluene vapors. The frequency readings

  17. Aporphine alkaloid contents increase with moderate nitrogen supply in Annona diversifolia Saff. (Annonaceae) seedlings during diurnal periods.

    Science.gov (United States)

    Orozco-Castillo, José Agustín; Cruz-Ortega, Rocío; Martinez-Vázquez, Mariano; González-Esquinca, Alma Rosa

    2016-10-01

    Aporphine alkaloids are secondary metabolites that are obtained in low levels from species of the Annonaceae family. Nitrogen addition may increase the alkaloid content in plants. However, previous studies published did not consider that nitrogen could change the alkaloid content throughout the day. We conducted this short-term study to determine the effects of nitrogen applied throughout the diurnal period on the aporphine alkaloids via measurements conducted on the roots, stems and leaves of Annona diversifolia seedlings. The 60-day-old seedlings were cultured with the addition of three levels of nitrogen (0, 30 and 60 mM), and alkaloid extracts were analysed using high-performance liquid chromatography. The highest total alkaloid content was measured in the treatment with moderate nitrogen supply. Further, the levels of aporphine alkaloids changed significantly in the first few hours of the diurnal period. We conclude that aporphine alkaloid content increased with moderate nitrogen supply and exhibited diurnal variation.

  18. Independent Recruitment of a Flavin-Dependent Monooxygenase for Safe Accumulation of Sequestered Pyrrolizidine Alkaloids in Grasshoppers and Moths

    OpenAIRE

    2012-01-01

    Several insect lineages have developed diverse strategies to sequester toxic pyrrolizidine alkaloids from food-plants for their own defense. Here, we show that in two highly divergent insect taxa, the hemimetabolous grasshoppers and the holometabolous butterflies, an almost identical strategy evolved independently for safe accumulation of pyrrolizidine alkaloids. This strategy involves a pyrrolizidine alkaloid N-oxygenase that transfers the pyrrolizidine alkaloids to their respective N-oxide,...

  19. Molekulare Identifizierung und Charakterisierung der Flavin-abhängigen Monooxygenasen in verschiedenen Pyrrolizidin-Alkaloid-adaptierten Insekten

    OpenAIRE

    2013-01-01

    Several insect lineages have developed diverse strategies to sequester toxic pyrrolizidine alkaloids from food-plants for their own defense. Here, we show that in two highly divergent insect taxa, the hemimetabolous grasshoppers and the holometabolous butterflies, an almost identical strategy evolved independently for safe accumulation of pyrrolizidine alkaloids. This strategy involves a pyrrolizidine alkaloid N-oxygenase that transfers the pyrrolizidine alkaloids to their respect...

  20. Structure/function analysis of PARP-1 in oxidative and nitrosative stress-induced monomeric ADPR formation.

    Directory of Open Access Journals (Sweden)

    Ben Buelow

    Full Text Available Poly adenosine diphosphate-ribose polymerase-1 (PARP-1 is a multifunctional enzyme that is involved in two major cellular responses to oxidative and nitrosative (O/N stress: detection and response to DNA damage via formation of protein-bound poly adenosine diphosphate-ribose (PAR, and formation of the soluble 2(nd messenger monomeric adenosine diphosphate-ribose (mADPR. Previous studies have delineated specific roles for several of PARP-1's structural domains in the context of its involvement in a DNA damage response. However, little is known about the relationship between the mechanisms through which PARP-1 participates in DNA damage detection/response and those involved in the generation of monomeric ADPR. To better understand the relationship between these events, we undertook a structure/function analysis of PARP-1 via reconstitution of PARP-1 deficient DT40 cells with PARP-1 variants deficient in catalysis, DNA binding, auto-PARylation, and PARP-1's BRCT protein interaction domain. Analysis of responses of the respective reconstituted cells to a model O/N stressor indicated that PARP-1 catalytic activity, DNA binding, and auto-PARylation are required for PARP-dependent mADPR formation, but that BRCT-mediated interactions are dispensable. As the BRCT domain is required for PARP-dependent recruitment of XRCC1 to sites of DNA damage, these results suggest that DNA repair and monomeric ADPR 2(nd messenger generation are parallel mechanisms through which PARP-1 modulates cellular responses to O/N stress.

  1. Monomeric Cu(Ⅱ) Complex Containing Chiral Phase-transfer Catalyst as Ligand and Its Asymmetrically Catalytic Reaction

    Institute of Scientific and Technical Information of China (English)

    QU Zhi-Rong; XIONG Ren-Gen

    2008-01-01

    The thermal treatment of CuCl2 with N-(4'-vinylbenzyl)cinchonidinitim chloride(L1)afforded a monomeric discrete homochiral copper(Ⅱ)complex N-4'-(vinylbenzyl)cinchonidinium trichlorocoprate(Ⅱ)(1).Their applications to the enantioselectively catalytic alkylation reaction of N-(diphenylmethylidene)glycine tert-butyl ester(3)show that the higher ee value observed in catalyst 1 than that in the corresponding free ligand L1 is probably due to the rigidity enhancement after the coordination of N atom of quinoline ring to the copper ion.

  2. Two-dimensional crystallization of monomeric bovine cytochrome c oxidase with bound cytochrome c in reconstituted lipid membranes.

    Science.gov (United States)

    Osuda, Yukiho; Shinzawa-Itoh, Kyoko; Tani, Kazutoshi; Maeda, Shintaro; Yoshikawa, Shinya; Tsukihara, Tomitake; Gerle, Christoph

    2016-06-01

    Mitochondrial cytochrome c oxidase utilizes electrons provided by cytochrome c for the active vectorial transport of protons across the inner mitochondrial membrane through the reduction of molecular oxygen to water. Direct structural evidence on the transient cytochrome c oxidase-cytochrome c complex thus far, however, remains elusive and its physiological relevant oligomeric form is unclear. Here, we report on the 2D crystallization of monomeric bovine cytochrome c oxidase with tightly bound cytochrome c at a molar ratio of 1:1 in reconstituted lipid membranes at the basic pH of 8.5 and low ionic strength.

  3. A convenient microwave-assisted synthesis of cinchona alkaloid-derived ligands

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    An efficient synthesis of cinchona alkaloid-derived ligands based on solvent-free microwave-assisted reaction was described. The coupling of 1,4-dichlorophthalazine or 3,6-dichloropyridazine with quinine, cinchonine or cinchonidine provide bis- or mono-cinchona alkaloid-derived ligands in moderate to good yields (52-89%) within 15 rain under optimum microwave conditions.

  4. Heterozygous P53 knockout mouse model for dehydropyrrolizidine alkaloid-induced carcinogenesis

    Science.gov (United States)

    Dehydropyrrolizidine alkaloids are a large, structurally diverse group of plant-derived protoxins that are potentially carcinogenic. With worldwide significance, these alkaloids can contaminate or be naturally present in the human food supply. To develop a small animal model that may be used to com...

  5. Alkaloid profiles, concentration, and pools in velvet lupine (Lupinus leucophyllus) over the growing season.

    Science.gov (United States)

    Lee, Stephen T; Ralphs, Michael H; Panter, Kip E; Cook, Daniel; Gardner, Dale R

    2007-01-01

    Lupinus leucophyllus is one of many lupine species known to contain toxic and/or teratogenic alkaloids that can cause congenital birth defects. The concentrations of total alkaloids and the individual major alkaloids were measured in three different years from different plant parts over the phenological development of the plant. All of the alkaloids were found in the different plant tissues throughout the growing season, although their levels varied in different tissues. Concentrations of total alkaloids and the individual alkaloids varied on an annual basis and in their distribution in the different tissues. Anagyrine levels were highest in the floral tissue, lupanine and unknown F accumulated to the greatest level in the vegetative tissue, and 5,6-dehydrolupanine accumulated to the highest level in the stem. These alkaloids appear to be in a metabolically active state with the teratogenic alkaloid anagyrine accumulating to its highest level in the developing seed. The latter is, thus, the phenological stage posing the greatest danger to grazing livestock.

  6. Soil-borne microorganisms and soil-type affect pyrrolizidine alkaloids in Jacobaea vulgaris

    NARCIS (Netherlands)

    Joosten, L.; Mulder, P.P.J.; Klinkhamer, P.G.L.; Veen, van J.A.

    2009-01-01

    Secondary metabolites like pyrrolizidine alkaloids (PAs) play a crucial part in plant defense. We studied the effects of soil-borne microorganisms and soil-type on pyrrolizidine alkaloids in roots and shoots of Jacobaea vulgaris. We used clones of two genotypes from a dune area (Meijendel), propagat

  7. The toxicity of Poison Dart Frog alkaloids against the Fire Ant (Solenopsis invicta)

    Science.gov (United States)

    Hundreds of alkaloids, representing over 20 structural classes, have been identified from the skin of neotropical poison frogs (Dendrobatidae). These alkaloids are derived from arthropod prey of the frogs, and are generally are believed to deter vertebrate predators. We developed a method to put ind...

  8. Soil-borne microorganisms and soil-type affect pyrrolizidine alkaloids in Jacobaea vulgaris

    NARCIS (Netherlands)

    Joosten, L.; Mulder, P.P.J.; Klinkhamer, P.G.L.; Veen, van J.A.

    2009-01-01

    Secondary metabolites like pyrrolizidine alkaloids (PAs) play a crucial part in plant defense. We studied the effects of soil-borne microorganisms and soil-type on pyrrolizidine alkaloids in roots and shoots of Jacobaea vulgaris. We used clones of two genotypes from a dune area (Meijendel),

  9. Renieramycins H and I, two novel alkaloids from the sponge Haliclona cribricutis Dendy

    Digital Repository Service at National Institute of Oceanography (India)

    Parameswaran, P.S.; Naik, C.G.; Kamat, S.Y.; Pramanik, B.N.

    The known alkaloid, mimosamycin 1, along with its moon- and di hydroxy derivaties, 4-hydroxy mimosamycin 2 and 1, 4-dihydroxymimosamycin 3 and two new dimeric alkaloids: namely renieramycins H and I 4 and 5 have been isolated from the MeOH extract...

  10. Pengaruh metode penyarian terhadap kadar alkaloid total daun jembirit (Tabernaemontana sphaerocarpa. BL dengan metode spektrofotometri visibel

    Directory of Open Access Journals (Sweden)

    Nina Salamah

    2017-06-01

    Full Text Available One of the plants which contain the alkaloid is a plant jembirit (Tabernaemontana sphaerocarpa BL.. Sap and leaves from this plant have been used to treat skin diseases and sprain. Alkaloid from jembirit plants showed potent cytotoxicity against various human cancer cells. The goal of this research is to find out the influence of the extraction method against the level of total alkaloid jembirit leaves. Jembirit leaves were extracted by maceration method and extraction with Soxhlet apparatus used ethanol 70 % as a solvent. Standardization of extracts was conducted by test of ash content, test of drying shrinkage, and extract yield. Qualitative analysis was conducted by alkaloid test. Determination of total alkaloid was analyzed with visible spectrophotometry method using Bromocresol green as complexing agent. The results showed that jembirit leaves contained alkaloid compounds. The percentage of total alkaloid with maceration and extraction with Soxhlet apparatus was 0.727% ± 0.0032, and 0.666% ± 0.0022, respectively. The stastitical analysis showed significance differences of total alkaloid levels between maceration method and extraction with Soxhlet apparatus based on the siginificancy value (0.001<0.005.

  11. Carry-over of pyrrolizidine alkaloids from feed to milk in dairy cows

    NARCIS (Netherlands)

    Hoogenboom, L.A.P.; Mulder, P.P.J.; Zeilmaker, M.J.; Top, van den H.J.; Remmelink, G.J.; Brandon, E.A.; Klijnstra, M.; Meijer, G.A.L.; Schothorst, R.; Egmond, van H.J.

    2011-01-01

    Pyrrolizidine alkaloids are toxins present in many plants belonging to the families of Asteraceae, Boraginaceae and Fabaceae. Particularly notorious are pyrrolizidine alkaloids present in ragwort species (Senecio), which are held responsible for hepatic disease in horses and cows and may lead to the

  12. Livestock Poisoning with Pyrrolizidine Alkaloid Containing Plants (Senecio, Crotalaria, Cynoglossum, Amsinckia, Heliotropium and Echium spp.)

    Science.gov (United States)

    Pyrrolizidine alkaloids (PAs) are potent liver toxins that have been identified in over 6,000 plants throughout the world. Alkaloids are nitrogen-based compounds with potent biological activity. About half of the identified PAs are toxic and several cause cancer (carcinogenic). PA-containing plants...

  13. CHINESE BITTERSWEET ALKALOID Ⅲ,A NEW COMPOUND FROM CELASTR US ANGULATUS

    Institute of Scientific and Technical Information of China (English)

    WEI-PING YIN; TIAN-ZENG ZHAO; JING-GUO FU

    2001-01-01

    A novel skeleton alkaloid named Chinese Bittersweet Alkaloid Ⅲ from the leaves of C. angulatus was reported. The structure and its stereochemistry were established by IR, 1Dand 2DNMR (1H-1HCOSY, HMQC, HMBC, NOESY), MS and elemental analysis.

  14. Anagyrine desensitization of peripheral nicotinic acetylcholine receptors. A potential biomarker of quinolizidine alkaloid teratogenesis in cattle.

    Science.gov (United States)

    Anagyrine, a teratogenic quinolizidine alkaloid found in certain Lupinus spp., has been proposed to undergo metabolism by pregnant cattle to a piperidine alkaloid which acts inhibit fetal movement, the putative mechanism behind crooked calf syndrome. The objective of this study was to test the hypot...

  15. Conformational, IR spectroscopic and electronic properties of conium alkaloids and their adducts with C60 fullerene

    Science.gov (United States)

    Zabolotnyi, M. A.; Prylutskyy, Yu I.; Poluyan, N. A.; Evstigneev, M. P.; Dovbeshko, G. I.

    2016-08-01

    Conformational, IR spectroscopic and electronic properties of the components of Conium alkaloids (Conium maculatum) in aqueous environment were determined by model calculations and experiment. With the help of FT-IR spectroscopy the possibility of formation of an adduct between γ-coniceine alkaloid and C60 fullerene was demonstrated, which is important for further application of conium analogues in biomedical purposes.

  16. Isolation of a minor nitro-alkaloid from the aerial parts of Duguetia furfuracea--Annonaceae.

    Science.gov (United States)

    Carollo, Carlos Alexandre; de Siqueira, Joao Maximo

    2009-01-01

    The refractionation of an alkaloidal extract of the leaves and twigs of Duguetia furfuracea has provided a minor aporphinoid alkaloid, named (+)-8-nitrous-isocorydine or (+)-1,2,3-trymethoxy-11-hydroxy-8-nitrous- aporphine. The structure of the new compound was elucidated by spectroscopic methods, notably 2D NMR and HRESIMS.

  17. Biological activity of the alkaloids of Erythroxylum coca and Erythroxylum novogranatense

    NARCIS (Netherlands)

    Salemink, C.A.; Novák, M.; Khan, I.

    1984-01-01

    The cultivated Erythroxylum varieties E. coca var. coca, E. coca var. ipadu, E. novogranatense var. novogranatense and E. novogranatense var. truxillense contain 18 alkaloids, identified so far, belonging to the tropanes, pyrrolidines and pyridines, with cocaine as the main alkaloid. The biological

  18. Recognition of pyrrolizidine alkaloid esters in the invasive aquatic plant Gymnocoronis spilanthoides (Asteraceae)

    Science.gov (United States)

    Introduction – The freshwater aquatic plant Gymnocoronis spilanthoides (Senegal tea plant, jazmín del bañado, Falscher Wasserfreund) is an invasive plant in many countries. Behavioural observations of pyrrolizidine alkaloid-pharmacophagous butterflies suggested the presence of pyrrolizidine alkaloid...

  19. Sources of the anti-implantation alkaloid yuehchukene in the genus Murraya.

    Science.gov (United States)

    Kong, Y C; Ng, K H; But, P P; Li, Q; Yu, S X; Zhang, H T; Cheng, K F; Soejarto, D D; Kan, W S; Waterman, P G

    1986-02-01

    The genus Murraya has been widely used in traditional medicine in east Asia. In view of the recent isolation of the anti-implantation alkaloid yuehchukene from M. paniculata a search has now been made for other natural sources of this alkaloid within the genus. In this paper we report findings for nine taxa of Murraya.

  20. The comparative toxicity of a reduced, crude comfrey (Symphytum officinale) alkaloid extract and the pure, comfrey-derived pyrrolizidine alkaloids, lycopsamine and intermedine in chicks (Gallus gallus domesticus)

    Science.gov (United States)

    Comfrey (Symphytum officinale), a commonly used herb, contains dehydropyrrolizidine alkaloids (DHPAs) that, as a group of bioactive metabolites, are potentially hepatotoxic, pneumotoxic, genotoxic and carcinogenic. Consequently, regulatory agencies and international health organizations have recomm...

  1. Differential alkaloid profile in Uncaria tomentosa micropropagated plantlets and root cultures.

    Science.gov (United States)

    Luna-Palencia, Gabriela R; Huerta-Heredia, Ariana A; Cerda-García-Rojas, Carlos M; Ramos-Valdivia, Ana C

    2013-05-01

    The alkaloids of Uncaria tomentosa micropropagated plantlets and root cultures were isolated and identified by NMR and mass spectrometry. Plantlets yielded pteropodine (1), isopteropodine (2), mitraphylline (3), isomitraphylline (4), uncarine F (5), speciophylline (6), rhynchophylline (7) and isorhynchophylline (8). In plantlets growing under continuous light, tetracyclic alkaloids 7 and 8 decreased from 20 ± 1.8 at 2 months to 2.2 ± 0.33 mg/g dry wt at 6 months, while the pentacyclic alkaloids 1-4 increased from 7.7 ± 1.4 to 15 ± 0.05 mg/g dry wt, supporting their biogenetic conversion. Micropropagated plantlets produced four times more alkaloids (27.6 ± 3.1 mg/g dry wt) than greenhouse plants. Plantlet roots yielded 3, 4, 8 and the glucoindole alkaloids 3α-dihydrocadambine (9) and dolichantoside (10), the last one not previously found in Uncaria.

  2. Alkaloids Induce Programmed Cell Death in Bloodstream Forms of Trypanosomes (Trypanosoma b. brucei

    Directory of Open Access Journals (Sweden)

    Michael Wink

    2008-10-01

    Full Text Available The potential induction of a programmed cell death (PCD in Trypanosoma b. brucei by 55 alkaloids of the quinoline, quinolizidine, isoquinoline, indole, terpene, tropane, steroid, and piperidine type was studied by measuring DNA fragmentation and changes in mitochondrial membrane potential. For comparison, the induction of apoptosis by the same alkaloids in human leukemia cells (Jurkat APO-S was tested. Several alkaloids of the isoquinoline, quinoline, indole and steroidal type (berberine, chelerythrine, emetine, sanguinarine, quinine, ajmalicine, ergotamine, harmine, vinblastine, vincristine, colchicine, chaconine, demissidine and veratridine induced programmed cell death, whereas quinolizidine, tropane, terpene and piperidine alkaloids were mostly inactive. Effective PCD induction (EC50 below 10 µM was caused in T. brucei by chelerythrine, emetine, sanguinarine, and chaconine. The active alkaloids can be characterized by their general property to inhibit protein biosynthesis, to intercalate DNA, to disturb membrane fluidity or to inhibit microtubule formation.

  3. The serum concentrations of lupine alkaloids in orally-dosed Holstein cattle.

    Science.gov (United States)

    Green, Benedict T; Lee, Stephen T; Welch, Kevin D; Gardner, Dale R; Stegelmeier, Bryan L; Davis, T Zane

    2015-06-01

    Teratogenic alkaloid-containing Lupinus spp. cause congenital defects known as crooked calf disease that is periodically economically devastating for the cattle industry. Previous research indicates that cattle breeds may eliminate plant toxins differently, potentially altering their susceptibility. The objective of this study was to describe the toxicokinetics in Holsteins of anagyrine, the teratogenic lupine alkaloid that produces crooked calf disease. Other alkaloids including lupanine, an unidentified alkaloid and 5,6-dehydrolupanine were also evaluated. Dried ground Lupinus leucophyllus was orally dosed to four Holstein steers and blood samples were collected for 96 h, analyzed for serum alkaloid concentrations and toxicokinetic parameters calculated. The serum elimination of anagyrine in Holstein steers was faster than those reported for beef breeds. This suggests that Holsteins may be less susceptible to lupine-induced crooked calf disease. Additional work is needed to confirm these findings and to verify if there is a breed difference in disease incidence or severity. Published by Elsevier Ltd.

  4. Bioactive heterocyclic alkaloids with diterpene structure isolated from traditional Chinese medicines.

    Science.gov (United States)

    Xu, Tengfei; Liu, Shu; Meng, Lulu; Pi, Zifeng; Song, Fengrui; Liu, Zhiqiang

    2016-07-15

    The diterpenoid alkaloids as one type of heterocyclic alkaloids have been found in many traditional herbal medicines, such as genus Consolida, Aconitum, and Delphinium (Ranunculaceae). Pharmacological researches have indicated that many diterpenoid alkaloids are the main bioactive components which have analgesic, anti-inflammatory, anti-microbial, anti-tumor, cardiotonic, and anti-arrhythmic activities. Studies focused on the determination, quantitation and pharmacological properties of these alkaloids have dramatically increased during the past few years. Up to now, newly discovered diterpenoid alkaloids with important biological activities have been isolated and synthesized. Considering their significant role and diffusely used in many disease treatments, we summarized the information of their analysis methods, bioactivity, metabolism and biotransformation in vivo as well as the pharmacological mechanisms. Based on above review, the further researches are suggested.

  5. INHIBITORY EFFECTS OF THE ALKALOIDS FROM Radix Caulophylli ON THE PROLIFERATION OF HUMAN VASCULAR ENDOTHELIAL CELL

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Objective To find an angiogenetic inhibitor from Radix Caulophylli (RC). Methods The extract of Radix Caulophylli was obtained by using 95% alcohol in water as solvent. Then, the total alkaloids of Radix Caulophylli was isolated from the extract by using a positive ion exchange resin column. An active part was found by a screening model of cell membrane chromatography (CMC) and further tested by the MTT method with emodin as a control. Results The total alkaloids of Radix Caulophylli was the active part by CMC and could significantly inhibit proliferation of ECV304 cells in MTT test. The inhibitory rate was 56.06% while the concentration of the total alkaloids of Radix Caulophylli was 19.63μg/mL. Conclusion The total alkaloids from Radix Caulophylli may be a new angiogenetic inhibitor, and mechanism of the total alkaloids on inhibitory angiogenesis still need to be further investigated.

  6. Biological activity of the alkaloids of Erythroxylum coca and Erythroxylum novogranatense.

    Science.gov (United States)

    Novák, M; Salemink, C A; Khan, I

    1984-05-01

    The cultivated Erythroxylum varieties E. coca var. coca, E. coca var. ipadu, E. novogranatense var. novogranatense and E. novogranatense var. truxillense contain 18 alkaloids, identified so far, belonging to the tropanes, pyrrolidines and pyridines, with cocaine as the main alkaloid. The biological activity of the following alkaloids has been reported in the literature: cocaine, cinnamoylcocaine, benzoylecgonine, methylecgonine, pseudotropine, benzoyltropine, tropacocaine, alpha- and beta-truxilline, hygrine, cuscohygrine and nicotine. The biological activity of cocaine and nicotine is not reviewed here, because it is discussed elsewhere in the literature. Hardly anything is known about the biological activity of the other alkaloids present in the four varieties mentioned. The biosynthesis of the coca alkaloids has been outlined.

  7. The use of genomics and metabolomics methods to quantify fungal endosymbionts and alkaloids in grasses.

    Science.gov (United States)

    Rasmussen, Susanne; Lane, Geoffrey A; Mace, Wade; Parsons, Anthony J; Fraser, Karl; Xue, Hong

    2012-01-01

    The association of plants with endosymbiotic micro-organisms poses a particular challenge to metabolomics studies. The presence of endosymbionts can alter metabolic profiles of plant tissues by introducing non-plant metabolites such as fungal specific alkaloids, and by metabolic interactions between the two organisms. An accurate quantification of the endosymbiont and its metabolites is therefore critical for studies of interactions between the two symbionts and the environment.Here, we describe methods that allow the quantification of the ryegrass Neotyphodium lolii fungal endosymbiont and major alkaloids in its host plant Lolium perenne. Fungal concentrations were quantified in total genomic DNA (gDNA) isolated from infected plant tissues by quantitative PCR (qPCR) using primers specific for chitinase A from N. lolii. To quantify the fungal alkaloids, we describe LC-MS based methods which provide coverage of a wide range of alkaloids of the indolediterpene and ergot alkaloid classes, together with peramine.

  8. Determining important parameters related to cyanobacterial alkaloid toxin exposure

    Energy Technology Data Exchange (ETDEWEB)

    Love, A H

    2005-09-16

    Science-based decision making required robust and high-fidelity mechanistic data about the system dynamics and impacts of system changes. Alkaloid cyanotoxins have the characteristics to warrant consideration for their potential threat. Since insufficient information is available to construct a systems model for the alkaloid cyanotoxins, saxitoxins, anatoxins, and anatoxin-a(S), an accurate assessments of these toxins as a potential threat for use for intentional contamination is not possible. Alkaloid cyanotoxin research that contributed to such a model has numerous areas of overlap for natural and intentional health effects issues that generates dual improvements to the state of the science. The use of sensitivity analyses of systems models can identify parameters that, when determined, result in the greatest impact to the overall system and may help to direct the most efficient use of research funding. This type of modeling-assisted experimentation may allow rapid progress for overall system understanding compared to observational or disciplinary research agendas. Assessment and management of risk from intentional contamination can be performed with greater confidence when mechanisms are known and the relationships between different components are validated. This level of understanding allows high-fidelity assessments that do not hamper legitimate possession of these toxins for research purposes, while preventing intentional contamination that would affect public health. It also allows for appropriate response to an intentional contamination event, even if the specific contamination had not been previous considered. Development of science-based decision making tools will only improve our ability to address the new requirements addressing potential threats to our nation.

  9. Tall fescue seed extraction and partial purification of ergot alkaloids

    Directory of Open Access Journals (Sweden)

    Lowell eBush

    2014-12-01

    Full Text Available Many substances in the tall fescue/endophyte association (Schedonorus arundinaceus/Epichloë coenophiala have biological activity. Of these compounds only the ergot alkaloids are known to have significant mammalian toxicity and the predominant ergot alkaloids are ergovaline and ergovalinine. Because synthetically produced ergovaline is difficult to obtain, we developed a seed extraction and partial purification protocol for ergovaline/ergovalinine that provided a biologically active product. Tall fescue seed was ground and packed into several different sized columns for liquid extraction. Smaller particle size and increased extraction time increased efficiency of extraction. Our largest column was a 114 × 52 × 61 cm (W×L×D stainless steel tub. Approximately 150 kg of seed could be extracted in this tub. The extraction was done with 80% ethanol. When the solvent front migrated to bottom of the column, flow was stopped and seed was allowed to steep for at least 48 h. Light was excluded from the solvent from the beginning of this step to the end of the purification process. Following elution, ethanol was removed from the eluate by evaporation at room temperature. Resulting syrup was freeze-dried. About 80% recovery of alkaloids was achieved with 18-fold increase in concentration of ergovaline. Initial purification of the dried product was accomplished by extracting with hexane/water (6:1, v/v and the hexane fraction was discarded. The aqueous fraction was extracted with chloroform, the aqueous layer discarded, after which the chloroform was removed with a resulting 20-fold increase of ergovaline. About 65% of the ergovaline was recovered from the chloroform residue for an overall recovery of 50%. The resultant partially purified ergovaline had biological activities in in vivo and in vitro bovine bioassays that approximate that of synthetic ergovaline.

  10. Tall fescue seed extraction and partial purification of ergot alkaloids.

    Science.gov (United States)

    Ji, Huihua; Fannin, F; Klotz, J; Bush, Lowell

    2014-01-01

    Many substances in the tall fescue/endophyte association (Schedonorus arundinaceus/Epichloë coenophiala) have biological activity. Of these compounds only the ergot alkaloids are known to have significant mammalian toxicity and the predominant ergot alkaloids are ergovaline and ergovalinine. Because synthetically produced ergovaline is difficult to obtain, we developed a seed extraction and partial purification protocol for ergovaline/ergovalinine that provided a biologically active product. Tall fescue seed was ground and packed into several different sized columns for liquid extraction. Smaller particle size and increased extraction time increased efficiency of extraction. Our largest column was a 114 × 52 × 61 cm (W × L × D) stainless steel tub. Approximately 150 kg of seed could be extracted in this tub. The extraction was done with 80% ethanol. When the solvent front migrated to bottom of the column, flow was stopped and seed was allowed to steep for at least 48 h. Light was excluded from the solvent from the beginning of this step to the end of the purification process. Following elution, ethanol was removed from the eluate by evaporation at room temperature and the resulting syrup was freeze-dried. About 80% recovery of alkaloids was achieved with 18-fold increase in concentration of ergovaline. Initial purification of the dried product was accomplished by extracting with hexane/water (6:1, v/v). The aqueous fraction was extracted with chloroform, the aqueous layer discarded, after which the chloroform was removed with a resulting 20-fold increase of ergovaline. About 65% of the ergovaline was recovered from the chloroform residue for an overall recovery of 50%. The resultant partially purified ergovaline had biological activities in in vivo and in vitro bovine bioassays that approximate that of synthetic ergovaline.

  11. Tall fescue seed extraction and partial purification of ergot alkaloids

    Science.gov (United States)

    Bush, Lowell

    2014-12-01

    Many substances in the tall fescue/endophyte association (Schedonorus arundinaceus/Epichloë coenophiala) have biological activity. Of these compounds only the ergot alkaloids are known to have significant mammalian toxicity and the predominant ergot alkaloids are ergovaline and ergovalinine. Because synthetically produced ergovaline is difficult to obtain, we developed a seed extraction and partial purification protocol for ergovaline/ergovalinine that provided a biologically active product. Tall fescue seed was ground and packed into several different sized columns for liquid extraction. Smaller particle size and increased extraction time increased efficiency of extraction. Our largest column was a 114 × 52 × 61 cm (W×L×D) stainless steel tub. Approximately 150 kg of seed could be extracted in this tub. The extraction was done with 80% ethanol. When the solvent front migrated to bottom of the column, flow was stopped and seed was allowed to steep for at least 48 h. Light was excluded from the solvent from the beginning of this step to the end of the purification process. Following elution, ethanol was removed from the eluate by evaporation at room temperature. Resulting syrup was freeze-dried. About 80% recovery of alkaloids was achieved with 18-fold increase in concentration of ergovaline. Initial purification of the dried product was accomplished by extracting with hexane/water (6:1, v/v) and the hexane fraction was discarded. The aqueous fraction was extracted with chloroform, the aqueous layer discarded, after which the chloroform was removed with a resulting 20-fold increase of ergovaline. About 65% of the ergovaline was recovered from the chloroform residue for an overall recovery of 50%. The resultant partially purified ergovaline had biological activities in in vivo and in vitro bovine bioassays that approximate that of synthetic ergovaline.

  12. Bromopyrrole Alkaloids as Lead Compounds against Protozoan Parasites

    Directory of Open Access Journals (Sweden)

    Deniz Tasdemir

    2010-07-01

    Full Text Available In the present study,13 bromopyrrole alkaloids, including the oroidin analogs hymenidin (2, dispacamide B (3 and dispacamide D (4, stevensine (5 and spongiacidin B (6, their derivatives lacking the imidazole ring bromoaldisin (7, longamide B (8 and longamide A (9, the dimeric oroidin derivatives sceptrin (10 and dibromopalau’amine (11, and the non-oroidin bromopyrrolohomoarginin (12, manzacidin A (13, and agelongine (14, obtained from marine sponges belonging to Axinella and Agelas generahave been screened in vitro against four parasitic protozoa, i.e., two Trypanosoma species (T. brucei rhodesiense and T. cruzi, Leishmania donovani and Plasmodium falciparum (K1 strain, a chloroquine resistant strain, responsible of human diseases with high morbidity and, in the case of malaria, high mortality. Our results indicate longamide B (8 and dibromopalau’amine (11 to be promising trypanocidal and antileishmanial agents, while dispacamide B (3 and spongiacidin B (6 emerge as antimalarial lead compounds.In addition,evaluation of the activity of the test alkaloids (2–14 against three different enzymes (PfFabI, PfFabG, PfFabZ involved in the de novo fatty acid biosynthesis pathway of P. falciparum (PfFAS-II identified bromopyrrolohomoarginin (12 as a potent inhibitor of PfFabZ. The structural similarity within the series of tested molecules allowed us to draw some preliminary structure-activity relationships. Tests against the mammalian L6 cells revealed important clues on therapeutic index of the metabolites. This is the first detailed study on the antiprotozoal potential of marine bromopyrrole alkaloids.

  13. [Long QRS tachycardia secondary to Aconitum napellus alkaloid ingestion].

    Science.gov (United States)

    Gaibazzi, Nicola; Gelmini, Gian Paolo; Montresor, Graziano; Canel, Daniela; Comini, Teresa; Fracalossi, Claudio; Martinetti, Claudio; Poeta, Maria Luisa; Ziacchi, Vigilio

    2002-08-01

    The roots and seeds of the aconite (Aconitum napellus) contain alkaloids with modulatory activity on the sodium voltage-dependent channels; most fatal cases have been determined by ventricular tachycardia and respiratory paralysis. The only established treatment is supportive. We report a case of poisoning from Aconitum napellus, ingested by a husband and wife who thought the plant was "mountain chicory". They both had tachyarrhythmias, but the husband had more malignant episodes of hemodynamically unstable wide QRS tachycardia and respiratory paralysis requiring mechanical ventilation.

  14. Bromopyrrole alkaloids from the Caribbean sponge Agelas cerebrum

    Energy Technology Data Exchange (ETDEWEB)

    Regalado, Erik L.; Laguna, Abilio, E-mail: erikluis18@gmail.co [Center of Marine Bioproducts, Havana (Cuba). Dept. of Chemistry; Mendiola, Judith [Institute of Tropical Medicine Pedro Kouri (IPK), Havana (Cuba). Dept. of Parasitology; Thomas, Olivier P. [Universite de Nice-Sophia Antipolis (France). Lab. de Chimie des Molecules Bioactives et des Aromes; Nogueiras, Clara [University of Havana, San Lazaro y L, Havana (Cuba). Faculty of Chemistry. Center of Natural Products

    2011-07-01

    Bioguided fractionation of Agelas cerebrum crude extract resulted in isolation of four bromopyrrole and four bromopyrrole aminoimidazole alkaloids, identified as 5-bromopyrrole-2-carboxylic acid (1), 4-bromopyrrole-2-carboxylic acid (2), 3,4-bromopyrrole-2-carboxylic acid (3), 4,5-bromopyrrole-2-carboxylic acid (4), oroidin (5), bromoageliferin (6), dibromoageliferin (7) and dibromosceptrin (8) on the basis of spectroscopic data analyses (UV, IR, HRMS, 1D and 2D NMR) and comparison with literature data. This is the first report of compounds 2 and 3 in a marine sponge belonging to the Agelas genus and the first evidence of the presence of 1 from a natural source. (author)

  15. Quinolizidines alkaloids: Petrosin and xestospongins from the sponge Oceanapia sp.

    Digital Repository Service at National Institute of Oceanography (India)

    Singh; Das, B.; Naik, C.G.

    , No. 5, September 2011, pp. 601–607. c© Indian Academy of Sciences. Quinolizidines alkaloids: Petrosin and xestospongins from the sponge Oceanapia sp. KEISHAM SARJIT SINGH a,∗ , BABULAL DAS b and CHANDRAKANT G NAIK a a Bioorganic Chemistry Laboratory... performed on QTOP (MS/MS) Applied Biosystem mass spectrometer. Column chro- matography was performed on silica gel (230–400 mesh or 60–120 mesh, Merck, Darmstadt, Germany or SRL, Pvt. Ltd, India) or Shephadex LH-20. 601 602 Keisham Sarjit Singh et al. 2...

  16. Pyridine alkaloids from Senna multijuga as acetylcholinesterase inhibitors.

    Science.gov (United States)

    Francisco, Welington; Pivatto, Marcos; Danuello, Amanda; Regasini, Luis O; Baccini, Luciene R; Young, Maria C M; Lopes, Norberto P; Lopes, João L C; Bolzani, Vanderlan S

    2012-03-23

    As part of an ongoing research project on Senna and Cassia species, five new pyridine alkaloids, namely, 12'-hydroxy-7'-multijuguinol (1), 12'-hydroxy-8'-multijuguinol (2), methyl multijuguinate (3), 7'-multijuguinol (4), and 8'-multijuguinol (5), were isolated from the leaves of Senna multijuga (syn. Cassiamultijuga). Their structures were elucidated on the basis of spectroscopic data analysis. Mass spectrometry was used for confirmation of the positions of the hydroxy groups in the side-chains of 1, 2, 4, and 5. All compounds exhibited weak in vitro acetylcholinesterase inhibitory activity as compared with the standard compound physostigmine.

  17. A Novel Alkaloid Isolated from Spiranthera atlantica (Rutaceae).

    Science.gov (United States)

    Rodrigues e Rocha, Michelle; da Cunha, Carolina Passos; Filho, Raimundo Braz; Vieira, Ivo J Curcino

    2016-03-01

    A novel alkaloid 3-hydroxy-4-(2-hydroxyethyl)-4'-methoxy-7'H-quinolino[2,1-b]quinazolin-7'-one, named atlanticol (1), was isolated from Spiranthera atlantica (Rutaceae), along with five known compounds: lupeol (3), γ-fagarine (4), skimmianine (5), 7-methoxy-1-methyl-2-phenyl-4-quinolone (6) and 8-methoxy-1-methyl-2-phenyl-4-quinolone (7). Compound 6 was isolated from the Spiranthera genus for the first time. These compounds were characterized based on their spectral data, mainly through one and two-dimensional NMR and mass spectra, but also involving comparison with literature data.

  18. A Novel Antimicrobial Phenanthrene Alkaloid from Bryopyllum pinnatum

    Directory of Open Access Journals (Sweden)

    Donatus Ebere Okwu

    2011-01-01

    Full Text Available Phenenthrene alkaloid identified as 1-ethanamino 7 hex-1-yne-5I-one phenanthrene was isolated from the ethanolic extract of the leaves of Bryophyllum pinnatum (syn. B. calcinum kalanchoe pinnata a versatile Nigeria medicinal plant. The structure was elucidated using NMR, IR, UV and MS spectral data. Antimicrobial studies showed that the isolated compound successfully inhibited Psuedomonas aeruginosa, Klebsiella pneumonia, Staphylococcus aureus, Escherichia coli, Candida albicans and Aspergillus niger. This result authenticates the use of bryophyllum pinantum in phytomedicine for disease prevention and treatment of infections.

  19. Aedes aegypti Larvicidal Sesquiterpene Alkaloids from Maytenus oblongata.

    Science.gov (United States)

    Touré, Seindé; Nirma, Charlotte; Falkowski, Michael; Dusfour, Isabelle; Boulogne, Isabelle; Jahn-Oyac, Arnaud; Coke, Maïra; Azam, Didier; Girod, Romain; Moriou, Céline; Odonne, Guillaume; Stien, Didier; Houël, Emeline; Eparvier, Véronique

    2017-02-24

    Four new sesquiterpene alkaloids (1-4) with a β-dihydroagrofuran skeleton and a new triterpenoid (5) were isolated from an ethyl acetate extract of Maytenus oblongata stems. Their structures were elucidated using 1D and 2D NMR spectroscopy as well as MS and ECD experiments. The M. oblongata stem EtOAc extract and the pure compounds isolated were tested for larvicidal activity against Aedes aegypti under laboratory conditions, and compounds 2 and 3 were found to be active.

  20. Phenolic dimers and an indole alkaloid from Campylospermum flavum (Ochnaceae).

    Science.gov (United States)

    Ndongo, Joseph Thierry; Shaaban, Mohamed; Mbing, Joséphine Ngo; Bikobo, Dominique Ngono; Atchadé, Alex de Théodore; Pegnyemb, Dieudonné Emmanuel; Laatsch, Hartmut

    2010-11-01

    From the leaves and stem bark of Campylospermum flavum (Ochnaceae), three compounds, namely 4‴-O-methylagathisflavone, flavumchalcone, and flavumindole have been isolated together with 10 known compounds, including three flavonoids, two biflavonoids, two alkaloids, two nitrile glucosides, and glucopyranosyl-β-sistosterol. The structures of these compounds and their relative configurations were established by 1D and 2D NMR experiments. The methanolic crude extracts of leaves and stem bark of C. flavum and compounds displayed a significant cytotoxicity towards Artemia salina larvae.

  1. Curare Alkaloids: Constituents of a Matis Dart Poison.

    Science.gov (United States)

    Malca Garcia, Gonzalo R; Hennig, Lothar; Shelukhina, Irina V; Kudryavtsev, Denis S; Bussmann, Rainer W; Tsetlin, Victor I; Giannis, Athanassios

    2015-11-25

    A phytochemical study of dart and arrow poison from the Matis tribe led to the identification of D-(-)-quinic acid, L-malic acid, ethyldimethylamine, magnoflorine, and five new bisbenzyltetrahydroisoquinoline alkaloids (BBIQAs), 1-5. D-Tubocurarine could not be identified among these products. BBIQA (3) contains a unique linkage at C-8 and C-11'. All structures were characterized by a combination of NMR and HRESIMS data. The effects of Matis poison and individual BBIQAs (1-3) on rat muscle nAChR expressed in Xenopus oocytes have been investigated using the two-electrode voltage clamp technique.

  2. An azafluorenone alkaloid and a megastigmane from Unonopsis lindmanii (Annonaceae)

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Nidia C., E-mail: nidiayoshida@usp.br [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Quimica; Siqueira, Joao M. de [Universidade Federal de Sao Joao Del Rei, Divinpolis, MG (Brazil). Departamento de Farmacia; Rodrigues, Ricardo P. [Universidade de Sao Paulo (USP), Ribeirao Preto, SP (Brazil). Faculdade de Ciencias Farmaceuticas; Correia, Rodolfo P. [Universidade de Sao Paulo (USP), SP (Brazil). Instituto de Ciencias Biomedicas; Garcez, Walmir S., E-mail: walmir.garcez@ufms.br [Universidade Federal de Mato Grosso do Sul (UFMS), Campo Grande, MS (Brazil). Departamento de Quimica

    2013-04-15

    The azafluorenone alkaloid 5,8-dimethoxy-7-hydroxy-1-methyl-4-azafluoren-9-one and the megastigman (-)-(5R*, 6S*)-megastigman-3-one-10,7-olide were isolated from aerial parts of Unonopsis lindmanii (Annonaceae), along with the known compounds (3S*,5S*,8R*)-3,5-dihydroxymegastigma-6,7-dien-9-one (grasshopper ketone), N-trans-feruloyltyramine, (-)-anonaine, (-)-asimilobine, liriodenine and (-)-syringaresinol. This is the first description of the presence of megastigmanes in Annonaceae. The structures of the compounds were elucidated based on spectroscopic data. (author)

  3. A New Prenylated Indole Diketopiperazine Alkaloid from Eurotium cristatum

    Directory of Open Access Journals (Sweden)

    Xianwei Zou

    2014-11-01

    Full Text Available A new prenylated indole diketopiperazine alkaloid, cristatumin F (1, and four known metabolites, echinulin (2, dehydroechinulin (3, neoechinulin A (4 and variecolorin O (5, were isolated from the crude extract of the fungus Eurotium cristatum. The structure of 1 was elucidated primarily by NMR and MS methods. The absolute configuration of 1 was assigned using Marfey’s method applied to its acid hydrolyzate. Cristatumin F (1 showed modest radical scavenging activity against DPPH radicals, and exhibited marginal attenuation of 3T3L1 pre-adipocytes.

  4. A new prenylated indole diketopiperazine alkaloid from Eurotium cristatum.

    Science.gov (United States)

    Zou, Xianwei; Li, Ying; Zhang, Xiaona; Li, Qian; Liu, Xuan; Huang, Yun; Tang, Tao; Zheng, Saijing; Wang, Weimiao; Tang, Jintian

    2014-11-03

    A new prenylated indole diketopiperazine alkaloid, cristatumin F (1), and four known metabolites, echinulin (2), dehydroechinulin (3), neoechinulin A (4) and variecolorin O (5), were isolated from the crude extract of the fungus Eurotium cristatum. The structure of 1 was elucidated primarily by NMR and MS methods. The absolute configuration of 1 was assigned using Marfey's method applied to its acid hydrolyzate. Cristatumin F (1) showed modest radical scavenging activity against DPPH radicals, and exhibited marginal attenuation of 3T3L1 pre-adipocytes.

  5. Hypolipidemic Effects of Alkaloids from Rhizoma Coptidis in Diet-Induced Hyperlipidemic Hamsters.

    Science.gov (United States)

    He, Kai; Kou, Shuming; Zou, Zongyao; Hu, Yinran; Feng, Min; Han, Bing; Li, Xuegang; Ye, Xiaoli

    2016-05-01

    This study was conducted to evaluate the antihyperlipidemic activity of five major alkaloids in Rhizoma Coptidis using high-fat- and high-cholesterol-induced hyperlipidemic hamsters. Hyperlipidemic hamsters were treated with coptisine, berberine, jatrorrhizine, palmatine, epiberberine, and total Rhizoma Coptidis alkaloids with a dose of 46.7 mg/kg × day for 140 days. Serum total cholesterol, triglyceride, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol, and total bile acids were examined after alkaloid treatment. The results showed that all therapy agents prevented body weight gain, reduced the serum total cholesterol, and increased the high-density lipoprotein cholesterol of hamsters. Berberine, jatrorrhizine, and total Rhizoma Coptidis alkaloids decreased the triglyceride level in hyperlipidemic hamsters, while coptisine, jatrorrhizine, palmatine, and total Rhizoma Coptidis alkaloids significantly suppressed the elevation of the low-density lipoprotein cholesterol level. The fecal excretion of bile acids was significantly elevated by berberine, coptisine, jatrorrhizine, palmatine, total Rhizoma Coptidis alkaloids, and orlistat. Notably, total Rhizoma Coptidis alkaloids possess a much stronger lipid-lowering effect than the pure Rhizoma Coptidis alkaloids. Quantitative reverse transcription-polymerase chain reaction analyses revealed that Rhizoma Coptidis alkaloids could retard the synthesis of cholesterol by downregulating the mRNA expression of 3-hydroxy-3-methyl glutaryl coenzyme A reductase and accelerate the clearance of lipids by upregulating the low-density lipoprotein receptor, cholesterol 7α-hydroxylase, and uncoupling protein-2 expression. These findings highlight the critical role of Rhizoma Coptidis alkaloids in hyperlipidemia treatment. Thus, they need to be considered in future therapeutic approaches.

  6. Unravelling the architecture and dynamics of tropane alkaloid biosynthesis pathways using metabolite correlation networks.

    Science.gov (United States)

    Nguyen, Thi-Kieu-Oanh; Jamali, Arash; Lanoue, Arnaud; Gontier, Eric; Dauwe, Rebecca

    2015-08-01

    The tropane alkaloid spectrum in Solanaceae is highly variable within and between species. Little is known about the topology and the coordination of the biosynthetic pathways leading to the variety of tropine and pseudotropine derived esters in the alkaloid spectrum, or about the metabolic dynamics induced by tropane alkaloid biosynthesis stimulating conditions. A good understanding of the metabolism, including all ramifications, is however necessary for the development of strategies to increase the abundance of pharmacologically interesting compounds such as hyoscyamine and scopolamine. The present study explores the tropane alkaloid metabolic pathways in an untargeted approach involving a correlation-based network analysis. Using GC-MS metabolite profiling, the variation and co-variation among tropane alkaloids and primary metabolites was monitored in 60 Datura innoxia Mill. individuals, of which half were exposed to tropane alkaloid biosynthesis stimulating conditions by co-culture with Agrobacterium rhizogenes. Considerable variation was evident in the relative proportions of the tropane alkaloids. Remodeling of the tropane alkaloid spectrum under co-culture with A. rhizogenes involved a specific and strong increase of hyoscyamine production and revealed that the accumulation of hyoscyamine, 3-tigloyloxy-6,7-epoxytropane, and 3-methylbutyryloxytropane was controlled independently of the majority of tropane alkaloids. Based on correlations between metabolites, we propose a biosynthetic origin of hygrine, the order of esterification of certain di-oxygenated tropanes, and that the rate of acetoxylation contributes to control of hyoscyamine production. Overall, this study shows that the biosynthesis of tropane alkaloids may be far more complex and finely controlled than previously expected.

  7. Conditions for homogeneous preparation of stable monomeric and oligomeric forms of activated Vip3A toxin from Bacillus thuringiensis.

    Science.gov (United States)

    Kunthic, Thittaya; Surya, Wahyu; Promdonkoy, Boonhiang; Torres, Jaume; Boonserm, Panadda

    2016-07-29

    Bacillus thuringiensis vegetative insecticidal proteins like Vip3A have been used for crop protection and to delay resistance to existing insecticidal Cry toxins. However, little is known about Vip3A's behavior or its mechanism of action, and a structural model is required. Herein, in an effort to facilitate future crystallization and functional studies, we have used the orthogonal biophysical techniques of light scattering and sedimentation to analyze the aggregation behavior and stability of trypsin-activated Vip3A toxin in solution. Both scattering and sedimentation data suggest that at pH 10 the toxin is monomeric and adopts an elongated shape, but after overnight incubation aggregation was observed at all pH values tested (5-12). The narrowest size distribution was observed at pH 7, but it was consistent with large oligomers of ~50 nm on average. The addition of β-D-glucopyranoside (OG) helped in achieving preparations that were stable and with a narrower particle size distribution. In this case, scattering was consistent with a 4-nm monomeric globular Vip3A form. After OG dialysis, 40-nm particles were detected, with a molecular weight consistent with homotetramers. Therefore, OG is proposed as the detergent of choice to obtain a Vip3A crystal for structural studies, either before (monomers) or after dialysis (tetramers).

  8. Structural analysis of the bright monomeric yellow-green fluorescent protein mNeonGreen obtained by directed evolution.

    Science.gov (United States)

    Clavel, Damien; Gotthard, Guillaume; von Stetten, David; De Sanctis, Daniele; Pasquier, Hélène; Lambert, Gerard G; Shaner, Nathan C; Royant, Antoine

    2016-12-01

    Until recently, genes coding for homologues of the autofluorescent protein GFP had only been identified in marine organisms from the phyla Cnidaria and Arthropoda. New fluorescent-protein genes have now been found in the phylum Chordata, coding for particularly bright oligomeric fluorescent proteins such as the tetrameric yellow fluorescent protein lanYFP from Branchiostoma lanceolatum. A successful monomerization attempt led to the development of the bright yellow-green fluorescent protein mNeonGreen. The structures of lanYFP and mNeonGreen have been determined and compared in order to rationalize the directed evolution process leading from a bright, tetrameric to a still bright, monomeric fluorescent protein. An unusual discolouration of crystals of mNeonGreen was observed after X-ray data collection, which was investigated using a combination of X-ray crystallography and UV-visible absorption and Raman spectroscopies, revealing the effects of specific radiation damage in the chromophore cavity. It is shown that X-rays rapidly lead to the protonation of the phenolate O atom of the chromophore and to the loss of its planarity at the methylene bridge.

  9. Processing and storage effects on monomeric anthocyanins, percent polymeric color, and antioxidant capacity of processed blueberry products.

    Science.gov (United States)

    Brownmiller, C; Howard, L R; Prior, R L

    2008-06-01

    This study evaluated the effects of processing and 6 mo of storage on total monomeric anthocyanins, percent polymeric color, and antioxidant capacity of blueberries that were canned in syrup (CS), canned in water (CW), pureed, and juiced (clarified and nonclarified). Total monomeric anthocyanins, percent polymeric color, and oxygen radical absorbing capacity (ORAC) assay using fluorescein (ORAC(FL)) were determined postprocessing after 1 d, and 1, 3, and 6 mo of storage. Thermal processing resulted in marked losses in total anthocyanins (28% to 59%) and ORAC(FL) values (43% to 71%) in all products, with the greatest losses occurring in clarified juices and the least in nonclarified juices. Storage at 25 degrees C for 6 mo resulted in dramatic losses in total anthocyanins, ranging from 62% in berries CW to 85% in clarified juices. This coincided with marked increases in percent polymeric color values of these products over the 6-mo storage. The ORAC(FL) values showed little change during storage, indicating that the formation of polymers compensated for the loss of antioxidant capacity due to anthocyanin degradation. Methods are needed to retain anthocyanins in thermally processed blueberries.

  10. Processing and storage effects on monomeric anthocyanins, percent polymeric color, and antioxidant capacity of processed black raspberry products.

    Science.gov (United States)

    Hager, A; Howard, L R; Prior, R L; Brownmiller, C

    2008-08-01

    This study evaluated the effects of processing and 6 mo of storage on total monomeric anthocyanins, percent polymeric color, and antioxidant capacity of black raspberries that were individually quick-frozen (IQF), canned-in-syrup, canned-in-water, pureed, and juiced (clarified and nonclarified). Total monomeric anthocyanins, percent polymeric color, and ORAC(FL) were determined 1 d postprocessing and after 1, 3, and 6 mo of storage. Thermal processing resulted in marked losses in total anthocyanins ranging from 37% in puree to 69% to 73% in nonclarified and clarified juices, respectively, but only the juices showed substantial losses (38% to 41%) in ORAC(FL). Storage at 25 degrees C of all thermally processed products resulted in dramatic losses in total anthocyanins ranging from 49% in canned-in-syrup to 75% in clarified juices. This coincided with marked increases in percent polymeric color values of these products over the 6-mo storage. ORAC(FL) values showed little change during storage, indicating that the formation of polymers compensated for the loss of antioxidant capacity due to anthocyanin degradation. Total anthocyanins and ORACFL of IQF berries were well retained during long-term storage at -20 degrees C.

  11. Interaction of Classical Platinum Agents with the Monomeric and Dimeric Atox1 Proteins: A Molecular Dynamics Simulation Study

    Directory of Open Access Journals (Sweden)

    Xiaolei Wang

    2013-12-01

    Full Text Available We carried out molecular dynamics simulations and free energy calculations for a series of binary and ternary models of the cisplatin, transplatin and oxaliplatin agents binding to a monomeric Atox1 protein and a dimeric Atox1 protein to investigate their interaction mechanisms. All three platinum agents could respectively combine with the monomeric Atox1 protein and the dimeric Atox1 protein to form a stable binary and ternary complex due to the covalent interaction of the platinum center with the Atox1 protein. The results suggested that the extra interaction from the oxaliplatin ligand–Atox1 protein interface increases its affinity only for the OxaliPt + Atox1 model. The binding of the oxaliplatin agent to the Atox1 protein might cause larger deformation of the protein than those of the cisplatin and transplatin agents due to the larger size of the oxaliplatin ligand. However, the extra interactions to facilitate the stabilities of the ternary CisPt + 2Atox1 and OxaliPt + 2Atox1 models come from the α1 helices and α2-β4 loops of the Atox1 protein–Atox1 protein interface due to the cis conformation of the platinum agents. The combinations of two Atox1 proteins in an asymmetric way in the three ternary models were analyzed. These investigations might provide detailed information for understanding the interaction mechanism of the platinum agents binding to the Atox1 protein in the cytoplasm.

  12. Pro-toxic dehydropyrrolizidine alkaloids in the traditional Andean herbal medicine “asmachilca”

    Science.gov (United States)

    Colegate, Steven M.; Boppré, Michael; Monzón, Julio; Betz, Joseph M.

    2015-01-01

    Ethnopharmacological relevance Asmachilca is a Peruvian medicinal herb preparation ostensibly derived from Eupatorium gayanum Wedd. = Aristeguietia gayana (Wedd.) R.M. King & H. Rob. (Asteraceae: Eupatorieae). Decoctions of the plant have a reported bronchodilation effect that is purported to be useful in the treatment of respiratory allergies, common cold and bronchial asthma. However, its attractiveness to pyrrolizidine alkaloid-pharmacophagous insects indicated a potential for toxicity for human consumers. Aim of the study To determine if commercial asmachilca samples, including fully processed herbal teas, contain potentially toxic 1,2-dehydropyrrolizidine alkaloids. Materials and methods Two brands of “Asmachilca” herbal tea bags and four other commercial samples of botanical materials for preparing asmachilca medicine were extracted and analyzed using HPLC-esi(+)MS and MS/MS for the characteristic retention times and mass spectra of known dehydropyrrolizidine alkaloids. Other suspected dehydropyrrolizidine alkaloids were tentatively identified based on MS/MS profiles and high resolution molecular weight determinations. Further structure elucidation of isolated alkaloids was based on 1D and 2D NMR spectroscopy. Results Asmachilca attracted many species of moths which are known to pharmacophagously gather dehydropyrrolizidine alkaloids. Analysis of 5 of the asmachilca samples revealed the major presence of the dehydropyrrolizidine alkaloid monoesters rinderine and supinine, and their N-oxides. The 6th sample was very similar but did not contain supinine or its N-oxide. Small quantities of other dehydropyrrolizidine alkaloid monoesters, including echinatine and intermedine, were also detected. In addition, two major metabolites, previously undescribed, were isolated and identified as dehydropyrrolizidine alkaloid monoesters with two “head-to-tail” linked viridifloric and/or trachelanthic acids. Estimates of total pyrrolizidine alkaloid and N

  13. Excretion of alkaloids by malpighian tubules of insects.

    Science.gov (United States)

    Maddrell, S H; Gardiner, B O

    1976-04-01

    Nicotine is transported at high rates by Malpighian tubules of larvae of Manduca sexta, Pieris brassicae and Rhodnius prolixus and the transport persists in the absence of alkaloid from the diet. In the fluid-secreting portion of Rhodnius tubules this transport is not coupled to ion transport, nor is it dependent on the physiological state of the animal. The transport, which can occur against a steep electrochemical gradient, shows saturation kinetics with a maximal rate of 700 pmol. min-1 per tubule and is half saturated at 2-3 mM. Nicotine transport independent of ion movements also occurs in the lower resorptive parts of Rhodnius tubules. Both portions of Rhodnius tubules can transport morphine and atropine. These alkaloids and nicotine compete with one naother and are presumed to be carried by the smae transport system. Nicotine transport in Rhodnius was unaffected by organic anions, such as amaranth and benzyl penicillin, or by the organic anion transport inhibitor, probenecid. Fluid secretion in 5-HT-stimulated tubules was reduced by atropine and nicotine, probably by blocking the 5-HT receptors. The Malpighian tubules of adult Calliphora erythrocephala and Musca domestica remove nicotine from bathing solutions, an unknown metabolic accumulating in the tubules. Adult P. brassicae and M. sexta do not exhibit transport of nicotine by their Malpighian tubules.

  14. Antiplasmodial Alkaloids from the Bark of Cryptocarya nigra (Lauraceae

    Directory of Open Access Journals (Sweden)

    Khalijah Awang

    2013-07-01

    Full Text Available A dichloromethane extract of the stem bark of Cryptocarya nigra showed strong in vitro inhibition of Plasmodium falciparum growth, with an IC50 value of 2.82 μg/mL. The phytochemical study of this extract has led to the isolation and characterization of four known alkaloids: (+-N-methylisococlaurine (1, atherosperminine (2, 2-hydroxyathersperminine (3, and noratherosperminine (4. Structural elucidation of all alkaloids was accomplished by means of high field 1D- and 2D-NMR, IR, UV and LCMS spectral data. The isolated extract constituents (+-N-methylisococlaurine (1, atherosperminine (2 and 2-hydroxy-atherosperminine (3 showed strong antiplasmodial activity, with IC50 values of 5.40, 5.80 and 0.75 μM, respectively. In addition, (+-N-methylisocolaurine (1 and atherosperminine (2 showed high antioxidant activity in a DPPH assay with IC50 values of 29.56 ug/mL and 54.53 ug/mL respectively. Compounds 1 and 2 also both showed high antioxidant activity in the FRAP assay, with percentages of 78.54 and 70.66 respectively and in the metal chelating assay, with IC50 values of 50.08 ug/mL and 42.87 ug/mL, respectively.

  15. Pyrrolizidine alkaloids in food and feed on the Belgian market.

    Science.gov (United States)

    Huybrechts, Bart; Callebaut, Alfons

    2015-01-01

    Pyrrolizidine alkaloids (PAs) are widely distributed plant toxins with species dependent hepatotoxic, carcinogenic, genotoxic and pneumotoxic risks. In a recent European Food Safety Authority (EFSA) opinion, only two data sets from one European country were received for honey, while one feed data set was included. No data are available for food or feed samples from the Belgian market. We developed an LC-MS/MS method, which allowed the detection and quantification of 16 PAs in a broad range of matrices in the sub ng g(-1) range. The method was validated in milk, honey and hay and applied to honey, tea (Camellia sinensis), scented tea, herbal tea, milk and feed samples bought on the Belgian market. The results confirmed that tea, scented tea, herbal tea and honey are important food sources of pyrrolizidine alkaloid contamination in Belgium. Furthermore, we detected PAs in 4 of 63 commercial milk samples. A high incidence rate of PAs in lucerne (alfalfa)-based horse feed and in rabbit feed was detected, while bird feed samples were less contaminated. We report for the first time the presence of monocrotaline, intermedine, lycopsamine, heliotrine and echimidine in cat food.

  16. New cytotoxic quinolone alkaloids from fruits of Evodia rutaecarpa.

    Science.gov (United States)

    Huang, Xin; Li, Wei; Yang, Xiu-Wei

    2012-06-01

    Three new quinolone alkaloids, 1-methyl-2-[7-hydroxy-(E)-9-tridecenyl]-4(1H)-quinolone (1), 1-methyl-2-[(Z)-4-nonenyl]-4(1H)-quinolone (2), 1-methyl-2-[(1E,5Z)-1,5-undecadienyl]-4(1H)-quinolone (3) and one new natural product, 1-methyl-2-[(E)-1-undecenyl]-4(1H)-quinolone (4), were isolated from the dried and nearly ripe fruits of Evodia rutaecarpa (Juss.) Benth., along with thirteen known compounds (5-17). In addition, one new artificial product, 1-methyl-2-[7-carbonyl-(E)-9-tridecenyl]-4(1H)-quinolone (1A) was also obtained. The structures of these compounds were determined by spectroscopic analyses. The cytotoxic activities of all of the compounds against the human cancer cell lines HL-60, N-87, H-460, and Hep G(2) cells were evaluated by MTT assay. The results showed that these alkaloids inhibited cell proliferation with IC(50) values between 14μM and 22μM.

  17. Modulatory Effects of Eschscholzia californica Alkaloids on Recombinant GABAA Receptors

    Directory of Open Access Journals (Sweden)

    Milan Fedurco

    2015-01-01

    Full Text Available The California poppy (Eschscholzia californica Cham. contains a variety of natural compounds including several alkaloids found exclusively in this plant. Because of the sedative, anxiolytic, and analgesic effects, this herb is currently sold in pharmacies in many countries. However, our understanding of these biological effects at the molecular level is still lacking. Alkaloids detected in E. californica could be hypothesized to act at GABAA receptors, which are widely expressed in the brain mainly at the inhibitory interneurons. Electrophysiological studies on a recombinant α1β2γ2 GABAA receptor showed no effect of N-methyllaurotetanine at concentrations lower than 30 μM. However, (S-reticuline behaved as positive allosteric modulator at the α3, α5, and α6 isoforms of GABAA receptors. The depressant properties of aerial parts of E. californica are assigned to chloride-current modulation by (S-reticuline at the α3β2γ2 and α5β2γ2 GABAA receptors. Interestingly, α1, α3, and α5 were not significantly affected by (R-reticuline, 1,2-tetrahydroreticuline, codeine, and morphine—suspected (S-reticuline metabolites in the rodent brain.

  18. New cycloartane saponin and monoterpenoid glucoindole alkaloids from Mussaenda luteola

    Science.gov (United States)

    Mohamed, Shaymaa M.; Backheet, Enaam Y.; Bayoumi, Soad A.; Ross, Samir A.

    2016-01-01

    A new cycloartane-type saponin with unusual hydroxylation at C-17 and a unique side chain, 9 (R), 19, 22 (S), 24 (R) bicyclolanost-3β, 12α, 16β, 17α tetrol-25-one 3-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranoside (1) and two new monoterpenoid glucoindole alkaloids, 10-methoxy pumiloside (2) and the previously chemically synthesized, 10-methoxy strictosidine (3) along with other five known compounds, 7α-morroniside (4), 7-epi-loganin (5), (7β)-7-O-methylmorroniside (6), 5(S)-5-carboxystrictisidine (7) and apigenin-7-O-neohesperidoside (8) were isolated from the aerial parts of Mussaenda luteola (Rubiaceae). The structural elucidation of the isolates was accomplished by extensive (1D and 2D NMR) spectroscopic data analysis and HR-ESI-MS. Compounds 4–8 were reported for the first time from the genus Mussaenda. Interestingly, this is the first report for the occurrence of the monoterpenoid glucoindole-type alkaloids in the genus which might be useful for the chemotaxonomic evaluation of the genus Mussaenda. All isolates were evaluated for their antiprotozoal activities. Compound 7 showed good antitrypanosomal activity with IC50 and IC90 values of 13.7 and 16.6 µM compared to IC50 and IC90 values of 13.06 and 28.99 µM for the positive control DFMO, difluoromethylornithine. PMID:26969788

  19. Individual and Geographic Variation of Skin Alkaloids in Three Swamp-Forest Species of Madagascan Poison Frogs (Mantella).

    Science.gov (United States)

    Andriamaharavo, Nirina R; Garraffo, H Martin; Spande, Thomas F; Giddings, Lesley-Ann; Vieites, David R; Vences, Miguel; Saporito, Ralph A

    2015-09-01

    Seventy skins of three mantellid frog species from Madagascan swamp-forest habitats, Mantella aurantiaca, M. crocea, and M. milotympanum, were individually examined for skin alkaloids using GC/MS. These poison frogs were found to differ significantly in their alkaloid composition from species of Mantella originating from non-flooded rainforest in eastern Madagascar, which were examined in earlier work. Only 16 of the previously detected 106 alkaloids were represented among the 60 alkaloids from the swamp-forest frogs of the present study. We hypothesize this difference is related mainly to habitat but cannot exclude a phylogenetic component as the three swamp-forest species are a closely related monophyletic group. The paucity of alkaloids with unbranched-carbon skeletons (ant-derived) and the commonness of alkaloids with branched-carbon skeletons (mite-derived) indicate that oribatid mites are a major source of alkaloids in these species of mantellids. Furthermore, most of the alkaloids have an oxygen atom in their formulae. Differences in alkaloids were observed among species, populations of the same species, and habitats. In M. aurantiaca, small geographic distances among populations were associated with differences in alkaloid profiles, with a remote third site illustrating even greater differences. The present study and an earlier study of three other mantellid species suggest that oribatid mites, and not ants, are the major source of alkaloids in the species of mantellids examined thus far.

  20. Mass-spectrometry-directed analysis and purification of pyrrolizidine alkaloid cis/trans isomers in Gynura japonica.

    Science.gov (United States)

    Fang, Lianxiang; Xiong, Aizhen; Yang, Xiao; Cheng, Wenzhi; Yang, Li; Wang, Zhengtao

    2014-08-01

    Pyrrolizidine alkaloids are highly hepatotoxic natural chemicals that produce irreversible chronic and acute hepatotoxic effects on human beings. Purification of large amounts of pyrrolizidine alkaloids is necessary for toxicity studies. In this study, an efficient method for targeted analysis and purification of pyrrolizidine alkaloid cis/trans isomers from herbal materials was developed for the first time. Targeted analysis of the hepatotoxic pyrrolizidine alkaloids was performed by liquid chromatography with tandem mass spectrometry (precursor ion scan and daughter ion scan), and the purification of pyrrolizidine alkaloids was achieved with a mass-directed auto purification system. The extraction and preparative liquid chromatography conditions were optimized. The developed method was applied to analysis of Gynura japonica (Thunb.) Juel., a herbal medicine traditionally used for detumescence and relieving pain but is potentially hepatotoxic as it contains pyrrolizidine alkaloids. Twelve pyrrolizidine alkaloids (six cis/trans isomer pairs) were identified with reference compounds or characterized by liquid chromatography with tandem mass spectrometry, and five individual pyrrolizidine alkaloids, including (E)-seneciphylline, seneciphylline, integerrimine, senecionine, and seneciphyllinine, were prepared from G. japonica roots with high efficiency. The results of this work provide a new technique for the preparation of large amounts of pyrrolizidine alkaloid reference substances, which will also benefit toxicological studies of pyrrolizidine alkaloids and treatments for pyrrolizidine alkaloid-induced toxicity.