Bioactive β-indoloquinazoline alkaloids from Oricia renieri
Jean Duplex Wansi1, Emmanuel Ngeufa Happi, Judith Liliane Djouaka Bavoua
1Department of Chemistry, University of Douala, Faculty of Science, Douala, Cameroon. jdwansi@yahoo.fr
Planta Medica
|September 20, 2011
Summary
Three new β-indoloquinazoline alkaloids were discovered from Oricia renieri stems. These compounds showed strong suppression of phagocytosis but limited antimicrobial and cytotoxic effects.
Area of Science:
- Natural Product Chemistry
- Pharmacology
Background:
- Oricia renieri is a plant source of bioactive alkaloids.
- β-indoloquinazoline alkaloids represent a class of compounds with potential therapeutic applications.
Purpose of the Study:
- To isolate and characterize new β-indoloquinazoline alkaloids from Oricia renieri.
- To evaluate the biological activities of isolated compounds, including antimicrobial, antifungal, and immunomodulatory effects.
Main Methods:
- Methanol extraction of Oricia renieri stems.
- Structure elucidation using comprehensive spectroscopic analyses (NMR, MS).
- Biological assays: antimicrobial (bacteria, fungi, oomycetes), phagocytosis assay, and cytotoxicity assay (PC-3 cell line).
Main Results:
- Isolation of three new alkaloids (orirenierine A, B, C) and eleven known compounds.
- Compounds 9-11 were reported for the first time in this genus.
- Weak antimicrobial activity (MICs > 1 mg/mL) observed.
- Compounds 1-4 and 11 significantly suppressed phagocytosis (IC50 = 2.6–6.5 µM).
- Low cytotoxicity against PC-3 cells (IC50 = 22.9–39.4 µM).
Conclusions:
- Oricia renieri is a rich source of β-indoloquinazoline alkaloids.
- New alkaloids orirenierine A-C possess significant immunomodulatory properties by suppressing phagocytosis.
- The isolated compounds exhibit a selective activity profile, with limited antimicrobial and cytotoxic effects.
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