Anti-HIV crotocascarin ω from Kenyan Croton dichogamus

Abstract

An anti-HIV methanol-soluble fraction of a 1:1 CH₂Cl₂:CH₃OH extract of twigs of a Kenyan Croton dichogamus yielded seven compounds, the new crotocascarin ω (1), the known β-oplopanone (2), dihydroconiferyl acetate (3), 3’(4’’-hydroxyphenyl)-propyl benzoate (4), lupeol, sitosterol and stigmasterol. Crotocascarin ω (90%) inhibited HIV-1 replication with an IC₅₀ value of 5.3 nM, and the compound was cytotoxic towards MT-4 cells presenting an IC₅₀ value of 84 µM. In silico modelling showed that the anti-HIV activity for compound 1 could be through the HIV-1 protease inhibition.

Graphical Abstract

Keywords:

• Anti-HIV activity
• Croton dichogamus
• crotocascarin ω
• β-oplopanone
• dihydroconiferyl acetate
• 3’(4’’-hydroxyphenyl)-propyl benzoate

Acknowledgments

EMT acknowledges University of Nairobi, Kenya Medical Research Institute and the Institute of Primate Research for their support toward the successful completion of the research work.

Institutional review board statement

The collection of the plant was performed after obtaining the required ethical approval from the Kenyatta National Hospital-University of Nairobi Ethics and Research Committee (KNH-UON ERC), approval number P992/12/2019.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was funded by United States International University- Africa Internal grant no. 10-2854.