PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Alkaloids”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1976

Lupin alkaloids from teratogenic and nonteratogenic lupins. IV. Concentration of total alkaloids, individual major alkaloids, and the teratogen anagyrine as a function of plant part and stage of growth and their relationship to crooked calf disease.

The concentrations of total alkaloids and individual major alkaloids including the teratogen anagyrine were measured in various plant parts of teratogenic lupins as the plants matured. All alkaloids including angyrine were high in concentration in above-ground parts early in growth and decreased as plants matured, except for an increase in mature, intact seeds. Seeds were highest, followed by early growth leaves and stems. Roots were lowest with mature leaves and stems only slightly higher. Pregnant cows have the greatest risk of giving birth to calves with crooked calf disease when the concentration of the teratogen anagyrine is highest and the cows are in the susceptible 40-75 day gestation period when ingesting the plant.

Abnormalities, Drug-Induced↗
PubMed2026

Amaryllidaceae Alkaloids and Isoquinoline Alkaloids: A Perspective on Historical Approaches to Pathway Elucidation.

Alkaloid biosynthesis is a central topic in plant specialized metabolism because many alkaloids have ecological, pharmacological, and biotechnological relevance. Isoquinoline alkaloids (IAs) and Amaryllidaceae alkaloids (AAs) are both connected to aromatic amino acid metabolism, but they differ in taxonomic distribution, scaffold-forming chemistry, pathway resolution, and biotechnological development. This review compares the historical and methodological trajectories that have shaped IA and AA pathway elucidation, from compound isolation, radiotracer experiments, and biochemical inference to transcriptomics, metabolomics, functional enzymology, isotope-guided active-tissue identification, regulatory studies, and heterologous pathway reconstruction. In IAs, especially benzylisoquinoline alkaloids, broad genomic and transcriptomic resources have supported candidate gene discovery and functional characterization of several branches, including morphinan, protoberberine, benzophenanthridine, and aporphine-related pathways. In contrast, AA biosynthesis has advanced more recently through function-driven approaches that clarified key steps such as N4OMT-mediated 4'-O-methylation, NBS/NR-mediated norbelladine formation, CYP96T-dependent regioselective oxidative coupling, and transient reconstruction of major scaffold-forming branches. Remaining gaps include the unresolved enzymatic formation of 3,4-dihydroxybenzaldehyde in AAs and incomplete functional validation across less-studied IA scaffold classes. By integrating biochemical logic, omics-guided discovery, enzyme evolution, tissue specificity, regulation, and synthetic biology, this review identifies priorities for future alkaloid pathway discovery and sustainable production.

3,4-dihydroxybenzaldehyde↗
PubMedDate not supplied

Alkaloids of papaver genus IX. Alkaloids of Glaucium vitellinum Boiss and Buhse, population Seerjan and Glaucium pulchrum Stapf, population Elika.

Glaucium vitellinum Boiss and Buhse. population Seerjan was shown to contain three major alkaloids, isocorydine (0.44%), protopine (0.42%), dicentrine (0.24%), and four minor alkaloids, tetrahydropalmatine (0.13%), muramine (0.12%), bulbocapnine (0.06%) and glaucine (0.01%). Glaucium pulchrum Stapf popllation Elika was shown to contain two major alkaloids, corydine (0.3%) and bulbocapnine (0.18%) and three minor alkaloids N-methylindcarpine (0.1%), isocorydine (0.03%) and protopine (0.01%). N-methyllindcarpine was found for the first time in the Papaveraceae and tetrahydropalmatine was detected for the first time in Glaucium.

Alkaloids↗
PubMedDate not supplied

Alkaloids of thalictrum. XX. Isolation, identification and structural elucidation of the alkaloids of the root of Thalictrum longistylum.

A study of the alkaloids of the roots of Thalictrum longistylum DC. resulted in the isolation of 12 alkaloids plus an artifact, 8-trichloromethyldihydroberberine. The 12 alkaloids were berberine, columbamine, jatrorrhizine, magnoflorine, methothalistyline, N-desmethylthalistyline, oxyberberine, palmatine, thalibrine, thalifendine, thaliglucinone, and thalistyline. Of these alkaloids, methothalistyline, N-desmethylthalistyline, and thalistyline are new compounds and with thaliglucinone possess hypotensive activity in dogs and rabbits. Methothalistyline, N-demethylthalistyline, thalistyline, and thalibrine were found to be active against Staphylococcus aureus and Mycobacterium smegmatis with with thalistyline being most active (50 microgram/ml).

Alkaloids↗
PubMed1975

Alkaloids of Vinca species V: structure elucidation of herbadine, an alkaloid isolated from Vinca libanotica.

Herbadine, a novel dihydroindole alkaloid, was isolated from the arterial parts of Vinca libanotica Zucc. (Apocynaceae). The physical and spectral data (UV, IR, NMR, and mass spectroscopy) indicated the alkaloid to be a derivative of aimaline. Comparative high-resolution NMR studies with quebrachidine and high-resolution mass spectral studies established the structure of the alkaloid to be 2-epi-3-hydroxyquebrachidine. Herbadine was previously isolated from another species by Russian workers and a structure was postulated. The current paper gives evidence for a corrected structure of herbadine.

Ajmaline↗
PubMed1977

New curare alkaloids. II. New bisbenzylisoquinoline alkaloids from Abuta grisebachii (Menispermaceae).

From Abuta grisebachii Triana & Planchon, Menispermacea used by Sanama tribe for the preparation of curare, five bisbenzylisoquinoline alkaloids have been isolated; four of them are tertiary (peinamine and three new alkaloids, 7-O-demethylpeinamine, N-methyl,7-O-demethylpeinamine and macolidine) and one is a new quaternary alkaloid called macoline. Their structures have been elucidated on the basis of chemical reactions and spectroscopic data.

Alkaloids↗
PubMedDate not supplied

Alkaloids of Carnegiea gigantea. Arizonine, a new tetrahydroisoquinoline alkaloid.

The alkaloid composition of the giant cactus, Carnegiea gigantea Br. & R., was studied. Chromatographic separation led to the isolation of four tetrahydroisoquinoline alkaloids: carnegine, salsolidine, gigantine and arizonine. The structure of the new natural product, arizonine, was establihsed by spectroscopic data and total synthesis via two independent routes. Salsolidine is reported for the first time in the cacti. Also new to this species are 3-methoxytyramine and 3,4-dimethoxypenethylamine, which were identified in the alkaloid extract by gas chromatography-mass spectrometry. Dopamine was isolated from fresh plant material.

Alkaloids↗
PubMedDate not supplied

Alkaloids of Thalictrum. XXI. Isolation and characterization of alkaloids from the roots of Thalictrum podocarpum.

Thirteen alkaloids, hernandezine, thalidezine, N-desmethylthalidezine, isothalidezine, thalistyline, thalistyline methodiiodide, N-desemethylthalistyline, berberine, columbamine, jatrorrhizine, palmatine, thalifendine, magnoflorine and the artifact, 8-trichloromethyldihydroberberine were isolated from the roots of Thalictrum podocarpum Humb. In addition, oxyberberine and thaliglucinone were obtained in very minor amounts and identified by tlc. Of these compounds, N-desmethylthalidezine and isothalidezine are new bisbenzylisoquinoline alkaloids. Sucrose was isolated from the alcoholic extract. Hernandezine, thalistyline, thalidezine, thalistyline methodiiodide and N-desmethylthalistyline were found to possess antimicrobial activity against Mycobacterium smegmatis at concentrations of 100 microgram/ml or less.

Alkaloids↗
PubMed1975

Alkaloids of Vinca rosea L. (Catharanthus roseus G. Don) XXXVI: Isolation and characterization of new dimeric alkaloids.

In a continuing effort to study thoroughly the alkaloids of Catharanthus roseus, new dimeric alkaloids were isolated and characterized. Structures are proposed for leurocolombine and vinamidine based on UV, IR, PMR, high-resolution mass spectrometry, and CMR. Pseudovincaleukoblastine diol was identified by PMR and mass spectrometry. Leurocolombine exhibited antimitotic activity and marginal antitumor activity against the Ridgeway osteogenic sarcoma.

Acetylation↗
PubMed1992

A new class of alkaloids from a dendrobatid poison frog: a structure for alkaloid 251F.

Alkaloids of a new class are present in skin extracts of the dendrobatid poison frog, Minyobates bombetes, of Colombia. The structure of the major alkaloid of this class, 251F, has been determined as a trimethylcyclopenta[b]quinolizidinemethanol 1 by nmr, gc-Ft-ir, and ms studies including ms-ms. At least nine congeners of 251F were detected in these extracts.

Alkaloids↗
PubMedDate not supplied

Alkaloids of Thalictrum XXVI. New hypotensive and other alkaloids from Thalictrum minus race B.

The roots of T. minus race B have yielded 9 alkaloids, thalirabine (1), thaliracebine (13), thalfine (19), thalfinine (20), thalrugosaminine (22), thalidasine (13), obaberine (24), thaliglucinone (25) and (S)-reticuline (26). The first two, possessing marked hypotensive activity, were assigned complete structures by physical and chemical methods. Thalfine (19) was given S-configuration at its one asymmetric center and was converted to thalfinine (20) and epithalfinine (21), thus the stereochemistry was established at one of the two optically active positions. The other alkaloids were identified by direct comparison with known samples. Antimicrobial testing showed thalirabine, thaliracebine, thalfine, and thalfinine to be active against Mycobacterium smegmatis.

Alkaloids↗
PubMedDate not supplied

Alkaloids of Thalictrum XXVII. New hypotensive aporphine-benzylisoquinoline derived dimeric alkaloids from Thalictrum minus race B.

The roots of T. minus race B have yielded, in addition to adiantifoline (1) previously isolated from this source, two new related alkaloids, thaliadine (2) and thaliadanine (5). Both were assigned complete structures by spectral methods and by chemical interconversion to adiantifoline or its product. O-Desmethyladiantifoline should have structure 14, rather than the previously reported 5. All three isolated alkaloids show hypotensive activity in rabbits, and thaliadanine (5) has antimicrobial activity against Mycobacterium smegmatis.

Alkaloids↗
PubMedDate not supplied

Alkaloids of Thalictrum. XV. Isolation and identification of the hypotensive alkaloids of the root of Thalictrum lucidum.

Sixteen alkaloids, namely homoaromoline, obaberine, O-methyl-thalicberine, oxyberberine, thalidasine, thaliglucinone, thalrugosine, obamegine, oxyacanthine, berberine, columbamine, jatrorrhizine, magnoflorine, palmatine, thalifendine and base A chloride, plus the artifact, 8-trichloromethyldihydroberberine, were isolated from the alkaloid fraction of the roots of Thalictrum lucidum L. Of these, obamegine, thalrugosine, O-methylthalicberine, thaliglucinone, obaberine and homoaromoline were found to possess hypotensive activity in normotensive dogs. Thalidasine, homoaromoline, thalrugosine, thaliglucinone, obamegine, jatrorrhizine, and columbamine were found to possess antimicrobial activity against Mycobacterium smegmatis at a concentration of 100 mug/ml or less.

Alkaloids↗
PubMed1976

Effects of ATP and magnesium ions on the fluorescence of harmala alkaloids. Restrictions for the use of harmala alkaloids as fluorescent probes for (Na+ + K+)-ATPase.

1. Harmine and harmaline were investigated as potentially useful fluorescent inhibitors of (Na+ + K+) activated ATPase. 29 From spectroscopic measurements both compounds were shown to form 1 : 1 complexes with ATP, the dissociation constants being 0.65 mM and 1.83 mM for harmine and harmaline respectively. Addition of Mg2+ and enzyme further affected these equilibria. 3. Although it was possible to demonstrate a competitive effect of harmine at the sodium-loading site of the enzyme, other inhibitory effects, including inhibitions of ouabain binding and the ouabain-insensitive ATPase were found. 4. It was concluded that the harmala alkaloids can inhibit (Na+ + K+)-activated ATPase in a complex way involving both Na- and ATP-binding sites. This severely limits their usefulness as spectroscopic probes.

Adenosine Triphosphatases↗