The taxonomic distribution, structure, and biological activity of halogenated alkaloids isolated from marine microorganisms and sponges are reviewed. The structures of nearly 140 natural bromoand iodo-containing alkaloids are shown.

Background & Aim: Papaver bracteatum Lindl.  (Papaverace) is an important pharmaceutical plant which contains isoqinoline alkaloids. Isoqinoline alkaloids constitute one distinct group of secondary metabolites of the Papaverace family. Codeine and thebaine are important alkaloids of Papaver bracteatum which use widely due to its medicinal properties. Therefore it is...

Two known phenanthroindolizidine alkaloids, (-)-(R)-13aalpha-antofine (1) and (-)-(R)-13aalpha-6-O-desmethylantofine (2), and two new natural products, (-)-(R)-13aalpha-secoantofine (3) and (-)-(R)-13aalpha-6-O-desmethylsecoantofine (4), were isolated from Cynanchum vincetoxicum. The structures of all compounds were established by means of NMR methods including COSY, NOESY, HSQC, and HMBC exper...

With few exceptions, aposematically colored poison frogs sequester defensive alkaloids, unchanged, from dietary arthropods. In the Neotropics, myrmicine and formicine ants and the siphonotid millipede Rhinotus purpureus are dietary sources for alkaloids in dendrobatid poison frogs, yet the arthropod sources for Mantella poison frogs in Madagascar remained unknown. We report GC-MS analyses of ex...

BACKGROUND Bitter herbs are important in Traditional Chinese Medicine and the Electronic Tongue (e-Tongue) is an instrument that can be trained to evaluate bitterness of bitter herbs and their constituents. The aim of this research was to evaluate bitterness of limonoids and alkaloids from Evodia rutaecarpa to demonstrate that they are main bitter material basic of E. rutaecarpa. METHODS Nine...

Lupinus, Baptisia, Sarothamnus, Diumal Rhythm, Photomixotrophic Cell Suspension Cultures, Quinolizidine Alkaloids Fluctuations of quinolizidine alkaloid content in leaflets of Lupinus polyphyllus, L. hartwegii, Baptisia australis, and Sarothamnus scoparius were studied over a 36 h period. The alkaloid contents reached their maximum at noon or early afternoon, and their minimum during the night....

Different group of alkaloids are produced during the symbiotic development of fungal endophytes of the genus Epichloë in grass. The structure and toxicity of the compounds vary considerably in mammalian herbivores and in crop pests. Alkaloids of the indole-diterpene group, of which lolitrem B is the most toxic, were first characterized in endophyte-infected perennial ryegrass, and are responsib...

Alkaloids produced by the fungal endophyte (Neotyphodium coenophialum) that infects tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] are a paradox to cattle production. Although certain alkaloids impart tall fescue with tolerances to environmental stresses, such as moisture, heat, and herbivory, ergot alkaloids produced by the endophyte can induce fescue toxicosis, a malady that adversely a...

Polyphagous molluscs such as H elix pom atia and Arion rufus generally do not feed on plants containing alkaloids. O f 19 species tested 10 species were totally avoided, the other 9 species were less attacked than Lactuca sativa, which was readily taken. Plants containing quinolizidine alkaloids were studied in detail. Those species with the a-pyridone alkaloids cytisine and N-methylcytisine we...