Five undescribed cyclopeptides from Cordyceps militaris

Area of Science:

• Natural Products Chemistry
• Medicinal Chemistry
• Pharmacology

Background:

• Cordyceps militaris is a fungus known for producing bioactive compounds.
• Cyclopeptides represent a class of natural products with diverse biological activities.
• Triple-negative breast cancer remains a challenging disease with limited targeted therapies.

Purpose of the Study:

• To isolate and characterize novel cyclopeptides from Cordyceps militaris.
• To evaluate the cytotoxic effects of these compounds on human triple-negative breast cancer cells.

Main Methods:

• Isolation of cyclopeptides using chromatographic techniques.
• Structure elucidation employing spectroscopic methods (NMR, MS) and X-ray crystallography.
• Computational methods for structure assignment.
• In vitro cytotoxicity assays using human triple-negative breast cancer cell lines.

Main Results:

• Five new cyclopeptides, Ustiloxins I-M (1-5), were isolated and characterized.
• The structures of Ustiloxins I and M (1 and 5) were confirmed by crystallography.
• Spectroscopic and computational analyses determined the structures of Ustiloxins J-L (2-4).
• Ustiloxins L (4) and M (5) exhibited cytotoxicity against triple-negative breast cancer cells with IC50 values of 64.29 μM and 28.89 μM, respectively.

Conclusions:

• Cordyceps militaris produces novel cyclopeptides with potential anticancer properties.
• Ustiloxins L and M show promising activity against human triple-negative breast cancer cells, warranting further investigation.