Metabolic profiling of Actaea species extracts using high performance liquid chromatography coupled with electrospray ionization time-of-flight mass spectrometry

Despite persistent questions about the safety of black cohosh (Actaea racemosa L., syn. Cimicifuga racemosa L.), its products continue to be one of the most popular botanical supplements in the United States market. Black cohosh products have been associated with cases of liver toxicity, but subsequent evaluation found some products to be adulterated with other related plants from the same genus. US FDA regulations require that black cohosh products be unadulterated, and correct identification of different species of Actaea is a key first step for their good manufacturing practice. We have developed a phytochemical method to distinguish four different groups of Actaea, including: species other than A. racemosa, Asian species, A. racemosa, and North American species other than A. racemosa. Using HPLC-TOF-ESI-MS technique and principal component analysis, we identified 15 chemical markers (1-3, 5-6, 8-10, 12, 16-21). Three marker compounds were unambiguously identified using authentic standards, and 12 marker compounds were tentatively identified by comparison of fragmentation patterns with previously reported data. The presence of these marker compounds is critical for discrimination among the four groups of closely related plants. The use of metabolic profiling to distinguish black cohosh from related species of Actaea has broader implications in the identification of markers to help authenticate other important medicinal plants.     

Detection of Actaea racemosa adulteration by thin-layer chromatography and combined thin-layer chromatography-bioluminescence

Actaea racemosa L. (black cohosh; syn. Cimicifuga racemosa L. Nutt.) is a native North American perennial whose root and rhizome preparations are commercially available as phytomedicines and dietary supplements, primarily for management of menopausal symptoms. Despite its wide use, methods that accurately identify processed A. racemosa are not well established; product adulteration remains a concern. Because of its similar appearance and growing locales, A. racemosa has been unintentionally mixed with other species of the genus, such as Actaea pachypoda Ell. (white cohosh) and more commonly Actaea podocarpa DC. (yellow cohosh). The genus Actaea also has 23 temperate species with numerous common names, which can also contribute to the misidentification of plant material. Consequently, a variety of Actaea spp. are common adulterants of commercially available black cohosh preparations. Thin-layer chromatography (TLC) and combined TLC-bioluminescence (Bioluminex) are efficient, economical, and effective techniques which provide characteristic patterns and toxicity profiles for each plant species. These data indicate that common black cohosh adulterants, such as yellow cohosh, can be differentiated from black cohosh by TLC and TLC-bioluminescence. This study also showed that unknown contaminants that were not detected using standard A. racemosa identity techniques were readily detected by TLC and TLC-bioluminescence.     

Synthesis of cimiracemate B, a phenylpropanoid found in Cimicifuga racemosa

The synthesis of the rare bioactive phenylpropanoid ester known as cimiracemate B (1) from black cohosh, Cimicifuga racemosa, is described. The procedure employs a coupling method using 1, l'-carbonyldiimidazole and methyltrifluoromethanesulfonate as coupling reagents in the presence of N-methylmorpholine.     

Identification of caffeic acid derivatives in Actea racemosa (Cimicifuga racemosa,black cohosh) by liquid chromatography/tandem mass spectrometry

Caffeic acid derivatives occurring in black cohosh [Cimicifuga racemosa (L.) Nutt., Actaea racemosa (Ranunculaceae)], some of which may have pharmacological activity, were analyzed using high-performance liquid chromatography (HPLC) electrospray ionization tandem mass spectrometry (ESI-MS/MS) with the aim of developing a methodology for their rapid identification in a complex plant matrix. Based on these studies, structurally characteristic product ions and neutral molecule losses were identified, which were then used during LC/MS/MS with product ion scanning, precursor scanning and constant neutral loss scanning to detect caffeic acid derivatives in a crude extract of black cohosh. Several caffeic acid derivatives were detected, and the identification of six of them were confirmed by comparison with authentic standards including caffeic acid, ferulic acid, isoferulic acid, fukinolic acid, cimicifugic acid A, and cimicifugic acid B. Four other compounds were detected that appeared to be caffeic acid derivatives based on LC/MS/MS retention times, molecular weights, and fragmentation patterns during MS/MS. Since standards were unavailable for these four compounds, they were tentatively identified using LC/MS/MS as cimicifugic acid E, cimicifugic acid F, dehydrocimicifugic acid A, and dehydrocimicifugic acid B. Dehydrocimicifugic acid A and dehydrocimicifugic acid B have not been reported previously to be constituents of black cohosh.     

Chemical Fingerprinting of Actaea racemosa (Black Cohosh) and Its Comparison Study with Closely Related Actaea Species (A. pachypoda, A. podocarpa, A. rubra) by HPLC

Black cohosh (Actaea recemosa) is a popular botanical used for women’s health. The rhizomes/roots used in black cohosh products are often collected from the wild; a correct identification is therefore crucial. An HPLC-ELSD method has been developed for the analysis of terpenoids in different Actaea species samples. The best results were obtained with a Phenomenex Discovery column using gradient mobile phase of water (0.1% acetic acid), acetonitrile (0.1% acetic acid) and reagent alcohol. Owing to their low UV absorption, the triterpene saponins were detected by evaporative light scattering. Elution was run at a flow rate of 1.0 mL min^?1. This paper discusses the use of the chemical fingerprinting technique as a means of identifying A. recemosa from three closely related species, A. pachypoda, A. podocarpa and A. rubra, respectively. This method suggests that the analytical method could be a useful method for quality control and identifying species.     

A triterpene glycoside from black cohosh that inhibits osteoclastogenesis by modulating RANKL and TNFalpha signaling pathways

Osteoporosis is a major age-related source of morbidity and mortality. Increased bone resorption mediated by osteoclasts is central to its pathogenesis. Cytokines, particularly RANKL and TNFalpha, are often increased under pathologic conditions, leading to enhanced osteoclastogenesis. Black cohosh (Actaea/Cimicifuga racemosa L), a popular herbal supplement for the treatment of menopausal symptoms, was recently shown to have the beneficial effect of preventing bone loss. Here, we demonstrate that 25-acetylcimigenol xylopyranoside (ACCX), a triterpenoid glycoside isolated from black cohosh, potently blocks in vitro osteoclastogenesis induced by either RANKL or TNFalpha. This blockage of osteoclastogenesis elicited by ACCX results from abrogation of the NF-kappaB and ERK pathways induced by either RANKL or TNFalpha, respectively. Importantly, this compound attenuates TNFalpha-induced bone loss in vivo. Therefore, ACCX represents a potential lead for the development of a new class of antiosteoporosis agents.     

DNA barcode identification of black cohosh herbal dietary supplements

Black cohosh (Actaea racemosa) herbal dietary supplements are commonly consumed to treat menopausal symptoms, but there are reports of adverse events and toxicities associated with their use. Accidental misidentification and/or deliberate adulteration results in harvesting other related species that are then marketed as black cohosh. Some of these species are known to be toxic to humans. We have identified two matK nucleotides that consistently distinguish black cohosh from related species. Using these nucleotides, an assay was able to correctly identify all of the black cohosh samples in the validation set. None of the other Actaea species in the validation set were falsely identified as black cohosh. Of 36 dietary supplements sequenced, 27 (75%) had a sequence that exactly matched black cohosh. The remaining nine samples (25%) had a sequence identical to that of three Asian Actaea species (A. cimicifuga, A. dahurica, and A. simplex). Manufacturers should routinely test plant material using a reliable assay to ensure accurate labeling.     

Oral administration of Cimicifuga racemosa extract attenuates immobilization stress-induced reactions

Dried rhizomes of Cimicifuga racemosa (CR), known as black cohosh, have been widely used as a herbal dietary supplement in the treatment of menopausal symptoms. Here we used experimental mouse stress models to investigate the role of anti-stress food factors, and found that a CR extract had stress-relieving effects. A single oral administration of CR extract (1,000 mg/kg) significantly attenuated plasma corticosterone and aspartate aminotransferase (AST) levels that had increased as a result of enforced immobilization. Bioassay-guided fractionation of the CR extract resulted in the isolation of 10 triterpenes, among which actein, 23-epi-26-deoxyactein, and cimiracemoside F (100 mg/kg, per os) were shown to contribute to the anti-stress effects. Furthermore, the CR extract significantly prevented the development of water immersion stress-induced gastric mucosal ulcers in rats. We propose that the CR extract might be suitable for the prevention and treatment of stress-related disorders.     

Fibrous Roots of Cimicifuga Are at Risk of Hepatotoxicity

The cause of liver damage by using black cohosh preparation has been concerned but remains unclear. After a preliminary investigation, the black cohosh medicinal materials sold in the market were adulterated with Asian cohosh (Cimicifuga) without removing the fibrous roots. The safety of Cimicifuga rhizome and fibrous roots is unknown and has not been reported. Therefore, in this paper, the rhizome and fibrous roots of Cimicifuga dahurica (Turcz.) Maxim (C. dahurica) were completely separated, extracted with 70% ethanol, and freeze-dried to obtain crude rhizome extract (RC) and fibrous roots extract (FRC). UHPLC-Q-TOF-MS was used to identify 39 compounds in the rhizome and fibrous roots of Cimicifuga, mainly saponins and phenolic acids. In the L-02 cytotoxicity experiment, the IC₅₀ of fibrous roots (1.26 mg/mL) was slightly lower than that of rhizomes (1.417 mg/mL). In the 90-day sub-chronic toxicity study, the FRC group significantly increased the level of white blood cells, ALP, ALT, AST, BILI and CHOL (p < 0.05); large area of granular degeneration and balloon degeneration occurred in liver tissue; and the expression of p-NF-kB in the nucleus increased in a dose-dependent manner. Overall, Fibrous roots of Cimicifuga are at risk of hepatotoxicity and should be strictly controlled and removed during the processing.     

Cimiracemoside a: A new cyclolanostanol xyloside from the rhizome of Cimicifuga racemosa

A new 9,19-cyclolanostane-type triterpene xyloside (1), from the rhizomes of Cimicifuga racemosa, has been isolated together with four known saponins; cimiaceroside A, 25-O-methylcimigenol-3-O-beta-D-xylopyranoside, 27-deoxyactein and 23-O-acetylshengmanol-3-O-beta-D-xylopyranoside. The structure of the new compound was established as 16beta,23:22beta,25-diepoxy-12-acetoxy-3beta,23,24b eta-trihydroxy-9,19-cyclolanost-7-ene-3-O-beta-D-xylopyranoside . For the structure elucidation, 1D- and 2D-NMR experiments and high resolution electrospray ionization Fourier transformation mass spectrometry (HRESIFTMS) were used.     

Podocarpaside, a triterpenoid possessing a new backbone from Actaea podocarpa

Podocarpaside (1), a novel arabinoside possessing a unique triterpene skeleton was isolated from Actaea podocarpa, a closely related species to black cohosh (dietary supplement used for menopausal disorders). Podocarpaside belongs to a new class of triterpenoids, for which the name "ranunculane" is proposed. Compound 1 possesses anticomplement activity. [structure: see text].     

High-content screening and mechanism-based evaluation of estrogenic botanical extracts

Symptoms associated with menopause can greatly affect the quality of life for women. Botanical dietary supplements have been viewed by the public as safe and effective despite a lack of evidence indicating a urgent necessity to standardize these supplements chemically and biologically. Seventeen plants were evaluated for estrogenic biological activity using standard assays: competitive estrogen receptor (ER) binding assay for both alpha and beta subtypes, transient transfection of the estrogen response element luciferase plasmid into MCF-7 cells expressing either ER alpha or ER beta, and the Ishikawa alkaline phosphatase induction assay for both estrogenic and antiestrogenic activities. Based on the combination of data pooled from these assays, the following was determined: a) a high rate of false positive activity for the competitive binding assays, b) some extracts had estrogenic activity despite a lack of ability to bind the ER, c) one extract exhibited selective estrogen receptor modulator (SERM) activity, and d) several extracts show additive/synergistic activity. Taken together, these data indicate a need to reprioritize the order in which the bioassays are performed for maximal efficiency of programs involving bioassay-guided fractionation. In addition, possible explanations for the conflicts in the literature over the estrogenicity of Cimicifuga racemosa (black cohosh) are suggested.     

Authentication of black cohosh (Actaea racemosa) dietary supplements based on chemometric evaluation of hydroxycinnamic acid esters and hydroxycinnamic acid amides

Analytical and Bioanalytical Chemistry - Ester and amide derivatives of hydroxycinnamic acids are found in black cohosh (Actaea racemosa) and other Actaea plants. These two compound groups were...     

Mending the bones with natural products

In this issue, Qiu and colleagues [1] demonstrate in vitro and in vivo activity of a triterpene glycoside from black cohosh. The isolated compound acts as a suppressor of osteoclastogenesis, targeting specifically RANKL, a member of the TNF superfamily.     

Two new triterpene glycosides with monomethyl malonate groups from the rhizome of Cimifuga foetida L

Two new 9,19-cycloartane triterpene glycosides 1-2, together with four known compounds--26-deoxyactein (3), actein (4), 7,8-didehydro-26-deoxyactein (5) and cimiaceroside B (6)--were isolated from the rhizome of Cimicifuga foetida. The new triterpene glycosides were identified as 23-O-methyl-24-deoxy-2'-O-(3'-methylmalonyl)-cimiaceroside B (1) and 2'-O-(3'-methylmalonyl)actein (2) based on analysis of their spectral data and chemical reactions.     

Separation ofCimicifuga racemosa triterpene glycosides by reversed phase high performance liquid chromatography and evaporative light scattering detection

Summary The main triterpene glycosides ofCimicifuga racemosa were separated by reversed phase HPLC, using a C-18 column, Evaporative Light Scattering (ELS) detection and a grient system consisting of water, acetonitrile and reagent alcohol. Within 35 min three main glycosides could be separated and quantified in the methanolic root extract with detection limits of 10.5, 15.6 and 31.6 μg·mL⁻¹ respectively. The method was successfully used, to analyzed differentCimicifuga racemosa market products, as well as to distinguish between otherCimicifuga samples from China.     

Cussosaponins A-E,triterpene saponins from the leaves of Cussonia racemosa,a Malagasy endemic plant

Five new triterpene saponins, cussosaponins A (2), B (3), C (4), D (5), and E (6), were isolated from the dried leaves of Cussonia racemosa BAKER. The structures of these new compounds were deduced on the basis of chemical and spectroscopic evidence.     

Two New Acetyl Cimicifugosides from the Rhizomes of Cimicifuga Racemosa

The rhizomes of Cimicifuga racemosa has been used as anti-inflammatory, analgesic and antipyretic agents in traditional Chinese medicine1. Some cimicifugosides belonging to highly oxygenated 9,19-cyclolanostane triterpene glycosides, in addition to cinnam…     

Three New Cycloartenol Triterpenoid Saponins from the Roots of Cimicifuga simplex Wormsk

Three new cycloartenol triterpene saponins, named shengmaxinsides A-C, have been isolated from the ethyl acetate soluble fraction of an ethanol extract of Cimicifuga simplex Wormsk roots. Their structures were established by chemical tests and detailed spectroscopic analysis as 25-O-acetyl-7,8-didehydrocimigenol-3-O-β-D-galactopyranoside (1), 7,8-didehydrocimigenol-3-O-β-D-galactopyranoside (2) and 7,8-didehydro-24S-O-acetylhydroshengmanol-3-O-β-D-galactopyranoside (3), respectively.     

Metabolism of Nω‐methylserotonin,a serotonergic constituent of black cohosh (Cimicifuga racemosa,L. (Nutt.)), by human liver microsomes

The roots/rhizomes of black cohosh (Cimicifuga racemosa L. (Nutt.) (syn. Actaea racemosa L.) are a popular dietary supplements among women for management of menopausal symptoms. Although not estrogenic, N_ω‐methylserotonin has been identified in black cohosh as a potent agonist of serotonin 5‐HT_1A and 5‐HT₇ receptors. In the present study, in vitro metabolism of N_ω‐methylserotonin was investigated to gain insights into aspects of the bioavailability of this compound. The major metabolic pathway was determined to be conversion into 5‐hydroxyindole acetaldehyde catalyzed by the monoamine oxidase A (MAO‐A). 5‐Hydroxyindole acetaldehyde could be further oxidized to form 5‐hydroxyindole acetic acid by the action of microsomal aldehyde dehydrogenase or reduced to 5‐hydroxy tryptophol by the action of aldehyde reductase. The cytochrome P450 enzymes had only a minor role in the metabolism of N_ω‐methylserotonin and then only when MAO‐A was inhibited. In many aspects, the metabolism of N_ω‐methylserotonin was similar to the metabolism of serotonin, suggesting that this compound is unlikely to elicit CNS effects due to rapid metabolism by the widely distributed MAO‐A. Copyright © 2014 John Wiley & Sons, Ltd.