Showing papers on "Indole alkaloid published in 1987"
TL;DR: The participation of the chloroplast in this pathway suggests that indole alkaloid intermediates enter and exit this compartment during the biosynthesis of vindoline.
Abstract: The subcellular localization of enzymes involved in indole alkaloid biosynthesis in leaves of Catharanthus roseus has been investigated. Tryptophan decarboxylase and strictosidine synthase which together produce strictosidine, the first indole alkaloid of this pathway, are both cytoplasmic enzymes. S-Adenosyl-l-methionine: 16-methoxy-2,3-dihydro-3-hydroxytabersonine-N-methyltransferase which catalyses the third to last step in vindoline biosynthesis could be localized in the chloroplasts of Catharanthus leaves and is specifically associated with thylakoids. Acetyl-coenzyme-A-deacetylvindoline-O-acetyltransferase which catalyses the last step in vindoline biosynthesis could also be localized in the cytoplasm. The participation of the chloroplast in this pathway suggests that indole alkaloid intermediates enter and exit this compartment during the biosynthesis of vindoline.
137 citations
TL;DR: The results demonstrate that fungal elicitors can be used to facilitate studies of the factors which regulate expression of indole alkaloid pathway enzymes and their ultimate pathway products.
79 citations
TL;DR: The structure of goniomitine, an indole alkaloid isolated from the root bark of Gonioma malagasy (Apocynoceae), was inferred from an analysis of its MS, 1H 13C NMR spectral data as discussed by the authors.
68 citations
TL;DR: In this article, a new indole alkaloid salvadoricine (I) has been isolated from Salvadora Persica and its structure was elucidated by spectral analysis and confirmed by synthesis.
44 citations
TL;DR: The intermediate accumulation of tryptamine and its later incorporation into ajmalicine indicated that the coordination of the two precursor pathways for the monoterpene indole alkaloid formation was not synchronized under the chosen culture conditions.
Abstract: The activity of geraniol- 10-hydroxylase was greatly increased when Catharanthus roseus cells were transferred to a production medium for monoterpene indole alkaloids. Its activity pattern showed a closer relationship than tryptophan decarboxylase to the pattern of indole alkaloid accumulation. The intermediate accumulation of tryptamine and its later incorporation into ajmalicine indicated that the coordination of the two precursor pathways for the monoterpene indole alkaloid formation was not synchronized under the chosen culture conditions. A better tuning of these two pathways may shorten the time period for induction of indole alkaloid biosynthesis.
40 citations
31 citations
TL;DR: A new indole alkaloid, alstonamine and a sitsirikine type indole acid, rhazimanine, have been isolated from the leaves of Alstonia scholaris as mentioned in this paper.
27 citations
22 citations
TL;DR: Three different strains of CATHARANTHUS ROSEUS cells were compared and no correlation was observed between the values of enzymatic activities and the contents of accumulated alkaloids.
Abstract: Three different strains of CATHARANTHUS ROSEUS cells were compared during one subculture with regard to tryptophan, tryptamine, ajmalicine, serpentine contents and tryptophane decarboxylase (TDC) (4) and Strictosidine synthase activities. The strains differed greatly in their accumulation of tryptamine and alkaloid. The TDC of all three strains showed the highest activity during the growth phase and declined sharply at the end of this phase. On the contrary, strictosidine synthase activity was the lowest during the growth phase and increased distinctly at the same time when the alkaloids were accumulating. By comparing the three strains with each other, no correlation was observed between the values of enzymatic activities and the contents of accumulated alkaloids.
18 citations
TL;DR: A fundamentally new method is described for the separation of the dimeric indole alkaloids vincristine and vinblastine from monomeric indoles alkaloid impurities using an RP-18 high-performance liquid chromatography column with a methanol-water mobile phase containing an inorganic acid and an unusually low concentration of inorganic buffer.
15 citations
TL;DR: The cell line CP-3 of Catharanthus roseus produces low levels of indole alkaloids during stationary phase of growth, but increased levels when transferred to growth-limiting production media, and the addition of elicitor to the cell suspension stimulated high levels of tryptamine biosynthesis and accumulation under all culture conditions.
Abstract: The cell line CP-3 of Catharanthus roseus produces low levels of indole alkaloids during stationary phase of growth, but increased levels when transferred to growth-limiting production media. Highest specific yields of alkaloids were usually achieved 8-15 days after transfer of the cells to the production medium. We attempted to reduce the time required for alkaloid production by altering preculture conditions, and by adding an elicitor preparation known to stimulate alkaloid accumulation in other cells. Reduction of 2,4-D in the last growth medium before transfer to production medium and a high initial inoculum load into the production medium resulted in rapid and greatest alkaloid accumulation (up to 2 mg ajmalicine/g dry mass or 40 mg/1 within 7 days). The addition of elicitor to the cell suspension stimulated high levels of tryptamine biosynthesis and accumulation under all culture conditions. Additionally, two cell lines derived from CP-3 cells and maintained on NAA/kinetin containing medium were selected for rapid growth in the absence of 2,4-D and were characterized with respect to their ajmalicine production. At a high inoculum load these cells produced up to 1.3 mg/g or 20 mg ajmalicine/1 when cultivated on the growth medium. The biotechnological utility of such cell lines is discussed.
TL;DR: Development of oxidation-reduction of the tryptophan or secologanin derived moieties occurs in three trends towards the series Pyricolla, Quebrachines and Nobilis, leading to dendrograms encompassing all seven series of Aspirosperma species.
TL;DR: A new indole alkaloid ajmalimine has been isolated from the roots of RAUWOLFIA SERPENTINA collected in Thailand by spectroscopic and chemical means.
Abstract: A new indole alkaloid ajmalimine has been isolated from the roots of Rauwolfia serpentina collected in Thailand. Its structure, 21-(trimethoxybenzoyl)-ajmaline, was established by spectroscopic and chemical means.
TL;DR: The alcoholic extract from the roots of Rauwolfia serpentina Benth afforded a new indole alkaloid which has been identified as 5β-methylpseudoyohimbane by spectroscopic studies as mentioned in this paper.