title: Divide and Conquer May Not Be the Optimal Approach to Retain the Desirable Estrogenic Attributes of the Cyclopia Nutraceutical Extract, SM6Met.
abstract: The genus Cyclopia, an indigenous South African fynbos plant used to prepare honeybush tea, contains phytoestrogenic compounds. An extract from C. subternata, SM6Met, displays three desirable estrogenic attributes for future development of a phytoestrogenic nutraceutical, namely, ERα antagonism, ERβ agonism, and also antagonism of E2-induced breast cancer cell proliferation. Activity-guided fractionation of SM6Met was used in an attempt to isolate and identify compounds conferring the desirable estrogenic profile to SM6Met. Initial liquid-liquid fractionation of SM6Met yielded a polar fraction (PF) and a non-polar fraction (NPF), with the desirable estrogenic attributes retained in the NPF. Subsequent high performance counter-current chromatography (HPCCC) fractionation of the NPF yielded three fractions (F1-F3). Interestingly, the fractions revealed separation of the previously demonstrated positive estrogenic attributes of the NPF into separate fractions, with F1 and F2 acting as ERα antagonists, only F2 inducing antagonism of E2-induced breast cancer cell proliferation and only F3 retaining robust ERβ agonist activity. In terms of major polyphenols, quantitative HPLC and liquid chromatography tandem mass spectrometry (LC-MS/MS) indicated that HPCCC fractionation resulted in a divergence of polyphenolic classes, with F1 emerging as the dihydrochalcone-rich fraction and F2 as the flavanone- and benzophenone-rich fraction, while the xanthones, flavones and phenolic acids were retained in F3. F3 was re-engineered into F3R by reassembling the major polyphenols identified in the fraction. F3R could, however, not replicate the effect of F3. In conclusion, although activity-guided fractionation results suggest that retention of all the desirable estrogenic attributes of the original SM6Met in one fraction is not an attainable goal, fractionation is a useful tool to enhance specific desirable estrogenic attributes.
authors.affiliation: Department of Biochemistry, Stellenbosch University, Stellenbosch, Western Cape, South Africa.
authors.forename: M
authors.initials: M
authors.lastname: Mortimer
authors.affiliation: Department of Biochemistry, Stellenbosch University, Stellenbosch, Western Cape, South Africa.
authors.forename: K
authors.initials: K
authors.lastname: Visser
authors.affiliation: Post-Harvest and Wine Technology Division, Agricultural Research Council of South Africa Infruitec-Nietvoorbij, Stellenbosch, Western Cape, South Africa.
authors.forename: D
authors.initials: D
authors.lastname: de Beer
authors.affiliation: Post-Harvest and Wine Technology Division, Agricultural Research Council of South Africa Infruitec-Nietvoorbij, Stellenbosch, Western Cape, South Africa; Department of Food Science, Stellenbosch University, Stellenbosch, Western Cape, South Africa.
authors.forename: E
authors.initials: E
authors.lastname: Joubert
authors.affiliation: Department of Biochemistry, Stellenbosch University, Stellenbosch, Western Cape, South Africa.
authors.forename: A
authors.initials: A
authors.lastname: Louw
mesh_terms: D049109:Cell Proliferation / Q000187:drug effects; D005591:Chemical Fractionation / Q000379:methods*; D002851:Chromatography, High Pressure Liquid; D002853:Chromatography, Liquid; D019587:Dietary Supplements; D004353:Drug Evaluation, Preclinical; D004958:Estradiol / Q000494:pharmacology; D047628:Estrogen Receptor alpha / Q000037:antagonists & inhibitors; D047629:Estrogen Receptor beta / Q000819:agonists; D007887:Fabaceae / Q000737:chemistry*; D057809:HEK293 Cells; D006801:Humans; D061986:MCF-7 Cells; D048789:Phytoestrogens / Q000302:isolation & purification* / Q000494:pharmacology*; D010936:Plant Extracts / Q000302:isolation & purification / Q000494:pharmacology; D053719:Tandem Mass Spectrometry
chemical_list: C506487:ESR1 protein, human; D047628:Estrogen Receptor alpha; D047629:Estrogen Receptor beta; D048789:Phytoestrogens; D010936:Plant Extracts; D004958:Estradiol