0000000000184351

AUTHOR

Mariko Kitajima

Substrate Specificity of Vinorine Hydroxylase, a Novel Membrane-bound Key Enzyme of Rauwolfia Indole Alkaloid Biosynthesis

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Anthraquinones from Ophiorrhiza pumila tissue and cell cultures

We have succeeded in initiating and establishing systems of tissue and cell cultures of Ophiorrhiza pumila. Examination of the constituents of the methanol extract of the cultured calli revealed the presence of 11 anthraquinones including two new ones whose structures have been rigorously proved using advanced spectroscopic methods. These findings demonstrated a remarkable difference in the constituents between the wild plants and the callus tissue or cultured cells; the former is devoid of anthraquinones and contains a variety of camptothecin-related alkaloids whereas the latter contains a significant amount of anthraquinones and shows no indication of the presence of alkaloids after sever…

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ChemInform Abstract: Structure and Synthesis of a New Indole Alkaloid, 19(S)-Hydroxy-Nb- methylraumacline, Obtained by the Biotransformation of Ajmaline in Plant Cell Cultures of Rauwolfia serpentina Benth.

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Isolation of Alkaloids from Cultured Hybrid Cells of Rauwolfia serpentina*Rhazya stricta.

Two monoterpenoid indole alkaloids and four β-carbolines were isolated from a hydrid cell suspension culture generated from two Apocynaceous plants, Rauwolfia serpentina Benth. and Rhazya stricta Decaisne. This indicates that the function of alkoloid biosynthesis is retained after hybrid formation and that alkaloids not previously detected in the parental plants or cell cultures are formed.

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Alkaloids from Rauwolfia serpentina cell cultures treated with ajmaline

Abstract A group of new alkaloids, the raumaclines, and some related alkaloids were isolated from Rauwolfia serpentina cell suspensions fed with high levels of ajmaline; their structures were determined and syntheses developed providing an essential prerequisite to the further study of their biosynthesis at the enzymatic level.

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Structure and Synthesis of a New Indole Alkaloid, 19 (S)-Hydroxy-Nb-methylraumacline, Obtained by the Biotransformation of Ajmaline in Plant Cell Cultures of Rauwolfia Serpentina Benth.

Abstract From the plant cell suspension cultures of Tauwolfia serpentina Benth ., which were cultivated in the alkaloid-production medium after feeding of ajmaline (1) , a new indole alkaloid 19- ( S )-hydroxy- N b -methylraumacline ( 4 ) was isolated. The structure of 4 first elucidated by spectroscopic analysis was determined by the chemical synthesis from ajmaline ( 1 ).

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Constituents of regenerated plants of Ophiorrhiza pumila; formation of a new glycocamptothecin and predominant formation of (3R)-deoxypumiloside over (3S)-congener

Abstract The regeneration of plantlets was successful from Ophiorrhiza pumila callus cultures, from which a new glucosyloxy camptothecin, 9-β-glucosyloxycamptothecin, together with 15 metabolites including six camptothecin-related alkaloids was isolated. (3S)-Deoxypumiloside, one of the plausible biogenetic precursors of camptothecin, could not be found, whereas the (3R) epimer was isolated from the regenerated plants.

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