ABSTRACT
Fifty-seven triterpene glycosides (Fig. 1) have been reported from the roots=rhizomes of C. racemosa,[1]
of which 23-epi-26-deoxyactein is generally recognized as the major component. Evaluation of 23-epi-26deoxyactein (formerly 27-deoxyactein), cimiracemoside F, and cimicifugoside, and their respective aglycons, for binding affinity toward ER-b revealed no significant affinity.[2] The roots=rhizomes also contain 18 aromatic acids.[1] Of these, caffeic acid has shown pregnant mare antigonadotropin activity,[3-5]
rat uterine antispasmodic activity,[6] and smooth muscle relaxant=antispasmolytic activity in the rat ileum[7]
and guinea pig ileum.[8] Ferulic acid has demonstrated luteinizing hormone (LH) release inhibition,[9] follicle stimulating hormone (FSH) release stimulation,[9]
antiestrogenic activity,[10] prolactin stimulation in cows[11] and inhibition in rats,[9] and uterine relaxant=antispasmolytic activity in rats.[12] Fukinolic acid has an estrogenic effect on MCF-7 cells with reference to estradiol.[13] These activities may correlate with, or prove useful in the determination of, the mechanism of action of black cohosh. Additionally a number of plant sterols and fatty acids generally regarded as ubiquitous in the plant kingdom, are contained in the roots=rhizomes, the biological activities of which, in all probability, do not relate to the mechanism of action.[1]
The weakly estrogenic formononetin has been reported in the plant.[14] However, recent studies using plant material collected from different sites in the eastern United States at different times of the year indicate that the plant does not contain formononetin.[15,16]
BOTANICAL DESCRIPTION
C. racemosa is an erect, smooth-stemmed, perennial 1-2.5 m in height. Large compound leaves are alternately arranged and triternate on short, clasping petioles. Basal leaf petioles are grooved in young
specimens. This shallow, narrow sulcus disappears as the petiole enlarges, whereas it remains present throughout life in the related eastern North American species C. rubifolia Kearney and C. americana Michx.[17] Terminal leaflets are acute and glabrous with sharp serrated margins often trilobate and occasionally bilobed. Fruits are ovoid follicles occurring sessile on the pedicel. The flowering structure, the raceme, is a long, wandlike structure with showy white flowers (Fig. 2). The flowers possess numerous characteristic stamens having slender filaments with distinctive white anthers.[18] The roots=rhizomes have the following features: branched and knotted structure; dark brown exterior; white and mealy or brown and waxy interior; upper surface with several buds and numerous large stem bases terminated, frequently, by deep, cup-shaped, radiating scars, each of which shows a radiate structure, or less frequently, by fibrous
strands; lower and lateral surfaces with numerous root scars and a few short roots; horny fracture; slight odor; bitter and acrid taste.[19]
EFFECTS ON CLIMACTERIC SYMPTOMS RELATED TO MENOPAUSE
With a history spanning almost 50 years of clinical study, mainly in Europe,[20] black cohosh is one of the more popular alternatives to hormone replacement therapy (HRT). Most of the clinical research has been performed on the commercially available Remifemin. The formulation and dosage of Remifemin used in human studies has changed over time, as shown in Table 1. However, other commercial formulations are available, as evident in Table 2. Most have still not been clinically studied.
