23-epi-26-Deoxyactein (27-Deoxyactein) has anti-inflammatory activity, it inhibits nitric oxide production by reducing iNOS expression without affecting activity of the enzyme. It also has anti-cancer activity, it can inhibit growth of the MCF7 human breast cancer cells and induce cell cycle arrest at G1.

Black cohosh rhizomes were extracted with methanol/water and fractionated by solvent-solvent partitioning to yield three fractions: hexane, ethyl acetate and water. The ethyl acetate fraction displayed the highest potency in two cell-based assays, growth inhibition and cell cycle analysis. This fraction inhibited growth of both the ER+ MCF7 and ER-MDA-MB-453 human breast cancer cell lines with IC50 values of about 20 and 10 micro g/ml, respectively. It also induced cell cycle arrest at G1 when tested at 30 micro g/ml and at G2/M at 60 micro g/ml in MCF7 cells. This suggests that the extract contains a mixture of components with the more active (or more abundant) causing G1 arrest and the less active causing G2/M arrest. We then examined specific components in this extract. The triterpene glycoside fraction obtained by polyamide column chromatography, and the specific triterpene glycosides actein, 23-epi-26-Deoxyactein and cimiracemoside A, inhibited growth of the MCF7 human breast cancer cells and induced cell cycle arrest at G1[1]