4 5 o dicaffeoylquinic acid

Extraction and chromatography solvents, ethanol (EtOH), methanol (MeOH), and acetic acid (AcOH) were HPLC certified. The polyphenol standards used in this study, such as chlorogenic acid, 3-O-caffeoylquinic acid, 1,5-O-dicaffeoylquinic acid, 3,4-O-dicaffeoylquinic acid, 3,5-O-dicaffeoylquinic acid and 4,5-O-dicaffeoylquinic acid, were purchased from PhytoLab GmbH & Co. KG (Vestenbergsgreuth, Germany). N-p-tosyl-l-phenylalanine chloromethyl ketone (TPCK), lipopolysaccharide (LPS), α-tochopherol and hydrogen peroxide solution (H₂O₂) were purchased from Sigma Aldrich Co. (Milano, Italy). Human TGF-β recombinant protein, 4,4-difluoro-3a,4a-diaza-s-indacene (BODIPY), dextran fluorescein 3000 MW and the Griess reagent [N-(1-naphthyl)ethylenediamine and sulfanilic acid] were purchased from Invitrogen-Life Technologies (Carlsbad, CA, USA).

Standards of flavonoids 7-O-β-glucosyl luteolin, apigenin, and 7-O-β-glucosyl apigenin were purchased from Extrasynthese (Genay, France). 5-O-caffeoylquinic acid, HPLC grade water, and acetonitrile were purchased from Sigma-Aldrich (Milan, Italy) and 3,4-O-dicaffeoylquinic acid, 4,5-O-dicaffeoylquinic acid and 3,5-O-dicaffeoylquinic acid were obtained from Phytolab (Vestenbergsgreuth, Germany).
Diethyl ether and a series of authentic reference compounds used for identification of the essential oil components were also purchased from Sigma-Aldrich (Milan, Italy).