Myricetin

Nineteen samples of chamomile were obtained from different manufacturers in Poland and are listed in Table 1 with their characterizations. The samples were homogenized at 20°C in a water-cooled grinder Knifetec 1095 (Foss Tecator, Höganäs, Sweden) and stored in desiccator which was protected from light.
Standards of phenolic acids—gallic, caffeic, syringic, p-coumaric, ferulic, and of flavonoids—rutin, myricetin, quercetin and kaempferol were purchased from ChromaDex (California, USA). HPLC grade methanol and acetonitrile were purchased from POCh (Gliwice, Poland) and J.T. Baker (Phillipsbusg, USA), respectively. Analytical grade ethanol, methanol, acetic acid, ferric chloride hexahydrate, 6-hydroxy-2,5,7,8-tetramethychroman-2-carboxylic acid (Trolox), 2,4,6-tris (2-pyridyl)-1,3,5-triazine (TPTZ), and 1,1-diphenyl-2-picrylhydrazol radical (DPPH) were purchased from POCh (Gliwice, Poland). Trifluoroacetic acid (TFA) was obtained from Sigma Aldrich (St. Louis, MO, USA). Redistillated water was prepared by triple distillation of water in a Destamat Bi-18 system (Heraeus Quarzglas, Hanau, Germany).

Ethanol and sodium carbonate were purchased from Avantor Performance Materials Poland (Gliwice, Poland). Gallic, m-coumaric, o-coumaric, p-coumaric, caffeic, 5-O-caffeoylqunic, ferulic, isoferulic, vanillic, salicylic, 3-hydroxybenzoic, 4-hydroxybenzoic, protocatechuic, syringic, rosmarinic acid, quercitrin, apigenin 7-O-glucoside, eriocitrin, taxifolin, 3-O-methylquercetin, isorhamnetin, isorhamnetin-3-O-glucoside, luteolin, kaempferol, rutin, hyperoside, isoquercetin, sakuranetin, aluminum chloride, and LC–MS grade acetonitrile were purchased from Sigma-Aldrich Chemical Co. (St. Louis, Mo, USA). Folin–Ciocalteu reagent was supplied by Chempur (Piekary Śląskie, Poland). Quercetin was purchased from Fluka (Buchs, Switzerland). Catechin, naringenin 7-O-glucoside, eriodictyol, luteolin-7-O-glucoside, naringenin 7-O-glucoside, luteolin 3,7-diglucoside, nicotiflorin, narcissoside, gentisic, sinapic acid, and myricetin were provided by ChromaDex (Irvine, CA, USA). Astragalin, apigenin, naringenin, kaempferol-3-rutinoside, and tiliroside were supplied by Roth (Karlsruhe, Germany). LC–MS grade water was prepared using a Millipore Direct-Q3 purification system (Bedford, MA, USA).

Standards of phenolic acids such as gallic (GA), chlorogenic (CGA), caffeic (CA), p-coumaric (pCA), ferulic (FA) and of flavonoids such as rutin (RUT), myricetin (M), quercetin (Q), and kaempferol (K) were purchased from ChromaDex (CA, USA). HPLC-grade methanol was purchased from Avantor Performance Materials Poland S.A., and trifluoroacetic acid (TFA) was from Sigma-Aldrich (St. Louis, MO, USA).