Cyclopeptide Alkaloids from Hymenocardia acida
Emmy Tuenter, Vassiliki Exarchou, Aliou Baldé1
1Research and Valorization Center on Medicinal Plants , Dubréka, Guinea-Conakry.
Journal of Natural Products
|June 29, 2016
Summary
Four cyclopeptide alkaloids from Hymenocardia acida roots showed moderate antiplasmodial activity. Hymenocardine N-oxide was the most potent, while three new compounds were identified, with limited cytotoxicity observed.
Area of Science:
- Natural Product Chemistry
- Pharmacology
- Medicinal Chemistry
Background:
- Hymenocardia acida is a plant source of bioactive compounds.
- Cyclopeptide alkaloids represent a class of natural products with diverse biological activities.
- Investigating the chemical constituents of Hymenocardia acida can lead to the discovery of novel therapeutic agents.
Purpose of the Study:
- To isolate and characterize cyclopeptide alkaloids from the root bark of Hymenocardia acida.
- To evaluate the antiplasmodial activity and cytotoxicity of the isolated alkaloids.
- To identify new natural products with potential pharmaceutical applications.
Main Methods:
- Isolation of compounds using semipreparative High-Performance Liquid Chromatography (HPLC) with Diode Array Detection (DAD) and Electrospray Ionization Mass Spectrometry (ESIMS).
- Structure elucidation utilizing spectroscopic techniques.
- Biological evaluation including antiplasmodial assays and cytotoxicity testing against MRC-5 cells.
Main Results:
- Four cyclopeptide alkaloids were isolated, including the known hymenocardine (1) and three novel compounds: hymenocardinol (2), hymenocardine N-oxide (3), and hymenocardine-H (4).
- All four compounds exhibited moderate antiplasmodial activity, with IC50 values between 12.2 and 27.9 μM.
- Hymenocardine N-oxide (3) demonstrated the highest potency (IC50 = 12.2 ± 6.6 μM).
- Compounds 2-4 showed no significant cytotoxicity (IC50 > 64.0 μM), while hymenocardine (1) displayed moderate cytotoxicity (IC50 = 51.1 ± 17.2 μM).
Conclusions:
- The root bark of Hymenocardia acida is a source of diverse cyclopeptide alkaloids.
- Hymenocardia acida alkaloids possess antiplasmodial properties, suggesting potential for malaria treatment.
- Hymenocardine N-oxide is a promising candidate for further investigation due to its potent antiplasmodial activity and low cytotoxicity.
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