Strophanthus boivinii

The Species

Strophanthus boivinii is an endemic liana of Madagascar's eastern humid rainforest, belonging to Apocynaceae - the family most relevant to pharmaceutical discovery on the island. In a single systematic screening event, researchers isolated Boivinide A, a cardenolide glycoside with an IC50 of 0.17 -M against human ovarian carcinoma cell lines - a potency that qualifies as a pharmaceutical lead compound by industry standards.

One species. One screening. One compound at 0.17 -M. The eastern rainforest contains thousands of related Apocynaceae - none systematically characterised at the genomic, transcriptomic, or paired metabolomic level.

Key Chemistry

Cardenolide glycosides are steroids with a specific lactone ring system. The class includes digitoxin and ouabain - drugs that have been in clinical use for over a century. The Madagascar Apocynaceae have evolved structurally distinct cardenolide variants under specific co-evolutionary pressures absent from continental relatives. Boivinide A represents one such variant: potent enough to be clinically interesting, structurally distinct enough to potentially avoid cross-resistance with existing cardenolide drugs.

The biosynthetic gene cluster encoding Boivinide A has never been identified. Paired genomic and transcriptomic data - the two layers most critical for BGC identification - do not exist for this species.