Planta Medica International Open 2017; 4(S 01): S1-S202
DOI: 10.1055/s-0037-1608486
Poster Session
Georg Thieme Verlag KG Stuttgart · New York

Evaluation of estrogenic activity of Trifolium pratense L. and Cimicifuga racemosa L. plant extracts and formulations using the planar-YES assay

S Bräm
1   Zurich University of Applied Sciences, Institute of Chemistry and Biotechnology, Phytopharmacy and Natural Products Research Group, Waedenswil, Switzerland
,
E Wolfram
1   Zurich University of Applied Sciences, Institute of Chemistry and Biotechnology, Phytopharmacy and Natural Products Research Group, Waedenswil, Switzerland
› Author Affiliations
Further Information

Publication History

Publication Date:
24 October 2017 (online)

 

Supplementation with natural estrogens, known as phytoestrogens are desirable for the treatment of women suffering from climacteric complaints after menopause. However, in patients with hormone-dependent cancers, such as specific types of breast cancer, the intake of phytoestrogens may be contraindicated, since some compounds are claimed to trigger the formation of metastasis-initiating cancer cells [1].

HPTLC is an analytical tool in quality control of medicinal plants extracts. Separated compounds from multicompound extracts are fixed on the solid silica phase like a compound library. By direct coupling of the Yeast Estrogen Screen (YES) on the HPTLC plate, this compound library can also be used for screening of estrogenic activity.

The reporter gene YES assay encoding the human estrogen receptor alpha (ERα) was adapted for the screening of Trifolium pratensis L. and Cimcifuga racemosa L. extracts and formulations [2,3]. The method is rapid and simple with no need for special sample preparation. Excipients such as microcrystalline cellulose, carboxymethylcellulose or polyvinyl pyrrolidone did not interfere with the method.

In samples of T. pratensis, pronounced fluorescent zones of Genistein and Biochanin A could be identified, indicating estrogen receptor affinity. The half maximal effective concentration (EC50) of Genistein and Biochanin A was 2.13 and 3.34 ng, respectively.

Cimicifugin showed weak estrogenic activity visible as fluorescent zones at applied masses of 4 µg. However, no ERα affinity was detected in C. racemosa samples. Formononetin interacted with ERα but was not detected in C. racemosa samples or commercial products.

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[3] McDonnell DP, Nawaz Z, Densmore C, Weigel NL, Pham TA, Clark JH, O'Malley BW. J Steroid Biochem Mol Biol 1991; 39: 291 – 297.