Myrycetin

The content of flavonols was determined according to the same conditions as phenolic acids. The content of flavonols was measured at a flow rate of 1.0 mL/min. The gradient programme started at the 1st minute with 95% of acidified water and it decreased to 20% at the 30th minute. The compounds were detected at a wavelength of 370 nm [60 (link)]. Compounds were identified by comparing their retention times with retention times of the standards (astragalin (kempferol 3-O-glucopyranoside), isoquercetin (quercetin-3-O-glucosidey), kaempferol (3,4′,5,7-tetrahydroxyflavone), quercetin (3,3′4′,5,7-pentahydroxyflavone), rutin (quercetin 3-rutinoside), myrycetin) (Sigma-Aldrich, Poznań, Poland) dissolved in methanol. The concentration of flavonols in samples were calculated using an external standard.

Acetonitrile (Sigma-Aldrich, Poland), acetic acid (99.9% purity, Chempur, Poland), deionized water (Sigma-Aldrich, Warsaw, Poland), methanol (Merck, Warsaw, Poland), ortho-phosphoric acid (Chempur, Warsaw, Poland), and phenolic compound standards, including ferulic acid (CAS 537-98-4), chlorogenic acid (CAS 327-97-9), kaempferol-3-O-glucoside (CAS 480-10-4), quercetin-3-O-glucoside (CAS 482-35-9), quercetin-3-O-rutinoside (CAS 207671-50-9), myrycetin (CAS 529-44-2), cyanidin-3-O-glucoside (CAS: 7084-24-4), and cyjanidin-3-O-rutinoside (CAS 18719-76-1), were used in this study. (Sigma-Aldrich, Supelco, Poland).