Estrogenic and Anti-estrogenic Constituents of Erythrina caffra.

Utilizing the pER8:GUS transgenic plant bioassay system to monitor estrogenic activity-guided fractionation, one new constituent, erycaffrain A, together with 11 known compounds were isolated from the ethanolic extract of Erythrina caffra. The structures of the isolated compounds were identified in combination with spectroscopic analyses. This is the first study reporting the estrogenic activity of E caffra. The new compound exhibited as a SREM, but also showed both estrogenic and anti-estrogenic activities in the MCF-7 cancer cell model. Several known phytoestrogens in this plant also revealed possible new functions for E. caffra stem.