Evaluation of the botanical authenticity and phytochemical profile of black cohosh products by high-performance liquid chromatography with selected ion monitoring liquid chromatography-mass spectrometry

Abstract

Black cohosh (Actaea racemosa L., syn. Cimicifuga racemosa L.) has become increasingly popular as a dietary supplement in the United States for the treatment of symptoms related to menopause, but the botanical authenticity of most products containing black cohosh has not been evaluated, nor is manufacturing highly regulated in the United States. In this study, 11 black cohosh products were analyzed for triterpene glycosides, phenolic constituents, and formononetin by high-performance liquid chromatography-photodiode array detection and a new selected ion monitoring liquid chromatography-mass spectrometry method. Three of the 11 products were found to contain the marker compound cimifugin and not cimiracemoside C, thereby indicating that these plants contain Asian Actaea instead of black cohosh. One product contained both black cohosh and an Asian Actaea species. For the products containing only black cohosh, there was significant product-to-product variability in the amounts of the selected triterpene glycosides and phenolic constituents, and as expected, no formononetin was detected.

Figure 1

Some of the triterpene glycosides and phenolic constituents reported from Actaea species.

Figure 2

SIM LC-MS chromatograms of black cohosh and three Asian Actaea species: (A) A. racemosa, (B) A. dahurica, (C) A. cimicifuga, and (D) A. yunnanensis. Peaks: a, 4; b, 7.

Figure 3

HPLC-PDA chromatograms for the phenolic constituents of black cohosh and several Actaea species (320 nm): (A) A. racemosa, (B) A. dahurica, (C) A. cimicifuga, and (D) A. yunnanensis. Peaks: a, 8; b, 9; c, 10; d, 11; e, 12; f, 13; and g and h, cimicifugic acids E and F.

Figure 4

LC-MS SIM scan at m/z 307 for 7, 469 for cimifugin glycoside, and 621 for 4. Extract A, 80% MeOH black cohosh extract.

Figure 5

HPLC-PDA chromatograms for phenolic constituents in three black cohosh alcoholic extracts and 11 black cohosh products (320 nm). Extracts: A, 80% MeOH; B, 75% EtOH; and C, 40% 2-propanol. Products: C-1 to C-7, black cohosh capsules; T-1 to T-4, black cohosh tablets. Peaks: a, 8; b, 9; c, 10; d, 11; e, 12; and f, 13.

Figure 6

HPLC-PDA chromatograms for triterpene glycosides in three black cohosh alcoholic extracts and 11 black cohosh products (203 nm). Extracts: A, 80% MeOH; B, 75% EtOH; and C, 40% 2-propanol. Products: C-1 to C-7, black cohosh capsules; T-1 to T-4, black cohosh tablets. Peaks: a, 1; b, 2; c, 3; d, unknown; e, unknown; f, 4; and g, 5.

Figure 7

LC-MS APCI-TIC spectrum and mass spectra for seven triterpene glycosides from the black cohosh product C-2. Peaks: a, 1; b, 2; c, 3; d, unknown; e, unknown; f, 4; and g, 5.