HPLC/DAD/MS and antioxidant activity of isoflavone-based food supplements.

Isoflavones are polyphenolic compounds found mainly in legumes the benefits of which have been widely studied and attributed in particular to their phytoestrogenic activity. The aim of this study was to evaluate the quali-quantitative composition of food supplements based on soy isoflavones ( Glycine Max L.) and red clover ( Trifolium pratense). Six commercial food supplements (five soy-based and one red clover-based) were analyzed by HPLC/DAD/MS. Genistein, daidzein, glycitein, biochanin A and formononetin derivatives (glycosides and acylglycosides) were identified in the analyzed samples. Also the antiradical activities (towards the DPPH• radical) and Fe2+chelating abilities were compared

Hydrolyzable Tannins from Sweet Chestnut Fractions Obtained by a Sustainable and Eco-friendly Industrial Process.

Sweet Chestnut ( Castanea sativa Mill.) wood extracts, rich in Hydrolyzable Tannins (HTs), are traditionally used in the tanning and textile industries, but recent studies suggest additional uses. The aim of this work is the HPLC-DAD-ESI-MS characterization of Sweet Chestnut aqueous extracts and fractions obtained through a membrane separation technology system without using other solvents, and the evaluation of their antioxidant and antiradical activities. Total tannins range between 2.7 and 138.4 mM; gallic acid ranges between 6% and 100%; castalagin and vescalagin range between 0% and 40%. Gallic Acid Equivalents, measured with the Folin-Ciocalteu test, range between 0.067 and 56.99g/100g extract weight; ORAC test results for the marketed fractions are 450.4 and 3050 μmol/g Trolox Equivalents/extract weight. EC50 values, measured with the DPPH test, range between 0.444 and 2.399 μM. These results suggest a new ecofriendly and economically sustainable method for obtaining chestnut fractions with differentiated, stable and reproducible chemical compositions. Such fractions can be marketed for innovative uses in several sectors