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Red Clover Tablets
» Red Clover Tablets contain Powdered Red Clover Extract. Tablets contain not less than 90.0 percent and not more than 110.0 percent of the labeled amount of Powdered Extract calculated as isoflavones.
Packaging and storage— Preserve in tight, light-resistant containers.
Labeling— The label states the Latin binomial and, following the official name, the article from which Tablets were prepared. The label also indicates the quantity, in mg, of Powdered Extract per Tablet. Label Tablets to indicate the content, in mg, of isoflavones per 100 mg of Powdered Extract.
Identification— The chromatogram of the Test solution exhibits peaks for daidzein, genistein, formononetin, and biochanin A at retention times that correspond to those in the chromatogram of Standard solution 1, as obtained in the test for Content of isoflavones. Calculate the ratio of 5,7-dihydroxyisoflavones to 7-hydroxyisoflavones by the formula:
(B + G)/(D + F),
in which B, G, D, and F are the contents of biochanin A, genistein, daidzein, and formononetin, respectively, as obtained in the test for Content of isoflavones: the ratio is between 0.1 and 10.0.
Microbial enumeration 2021 It meets the requirements of the tests for absence of Salmonella species and Escherichia coli. The total aerobic microbial count does not exceed 104 cfu per g, the total combined molds and yeasts count does not exceed 103 cfu per g, and the enterobacterial count is not less than 103 cfu per g.
Disintegration 2040: meet the requirements for disintegration of botanical dosage forms.
Weight variation 2091: meet the requirements.
Content of isoflavones—
Solvent, Solution A, Solution B, Mobile phase, Standard solution 1, Standard solution 2, and Chromatographic system— Proceed as directed in the test for Content of isoflavones under Red Clover.
Test solution— Accurately weigh not fewer than 20 Tablets, and pulverize, using a mortar and pestle. Transfer an accurately weighed quantity of the powder, equivalent to 40 mg of the labeled amount of isoflavones, to a 250-mL volumetric flask. Add 15 mL of water, shake to disperse the powder, add 15 mL of dehydrated alcohol and about 200 mL of Solvent, and sonicate for 30 minutes. If dark particles are present in the bottom of the flask, sonicate again for an additional 10 minutes or until they disappear. Cool to room temperature, and dilute with Solvent to volume. Transfer 50.0 mL of the resulting solution to a round-bottom flask, and evaporate to dryness under vacuum. Add 15 mL of 2 N hydrochloric acid, and heat in a water bath for 30 minutes. Quantitatively transfer this solution with the aid of about 15 mL of alcohol, to a 50-mL volumetric flask, and dilute with Solvent to volume. Pass 5 mL of the solution through a filter having a 0.45-µm porosity, discarding the first 4 mL of the filtrate. Collect the remaining 1 mL of filtrate for testing.
Procedure— Proceed as directed in the test for Content of isoflavones under Red Clover. Calculate the content of isoflavones, in mg, in the portion of Tablets taken by the formula:
250FC(rU / rS),
in which the terms are as defined therein.
Residual solvents 467: meet the requirements.
(Official January 1, 2007)
Auxiliary Information— Staff Liaison : Maged H. Sharaf, Ph.D., Senior Scientist
Expert Committee : (DSB05) Dietary Supplements - Botanicals
USP29–NF24 Page 2311
Pharmacopeial Forum : Volume No. 28(3) Page 812
Phone Number : 1-301-816-8318