Sinapic acid

Acetonitrile and methanol (HPLC grade) were purchased from Merck (Darmstadt, Germany). Ultrapure water was made using a Direct-Q 8 UV-R water purification system (Millipore, Billerica, MA, USA). Standard components of chlorogenic acid, cryptochlorogenic acid, neochlorogenic acid, isochlorogenic acid A, isochlorogenic acid B, isochlorogenic acid C, 3-O-feruloylquinic acid, 5-O-feruloylquinic acid, cinnamic acid, caffeic acid, ferulic acid, coumaric acid, sinapic acid, luteolin, apigenin, luteoloside, rutin, apigenin-7-O-glucoside, isorhamnetin-3-O-glucoside, quercetin-3-O-glucoside, loganin, vogeloside were obtained from Shanghai Yuanye Biotechnology Co. Ltd. (Shanghai, China).

Gallic acid, p-hydroxybenzoic acid, ferulic acid, trans-cinnamic acid, p-coumaric acid, benzoic acid, ellagic acid, protocatechuic acid, sinapic acid, caffeic acid, quercetin, rutin, taxifolin, isoquercitrin, catechin, gallocatechin, epicatechin, vitexin, genistin, daidzin, phloroglucinol, quinic acid, and 3,4-dihdyroxyphenylaceticacid were obtained from Yuanye Bio-Technology Co., Ltd. (Shanghai, China). Procyanidin B1, procyanidin B2, and kaempferol-3-O-rutinoside were obtained from Chengdu Pusi Biotechnology Co., Ltd. (Chengdu, China). 2,20-azinobis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS), 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,4,6tri(pyridin-2-yl)-1,3,5-triazine (TPTZ), (±)-6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox), fluorescein, 3′,6′-dihydroxyspiro [isobenzofuran-1 (3 H),9′-(9 H) xanthene]-3-one (FL), 2,2′-azobis (2-amidinopropane) dihydrochloride (AAPH), and EDTA-2Na were purchased from Aladdin Biochemical Technology Co., Ltd. (Shanghai, China). Thermo Fisher Scientific (Waltham, MA, USA) provided the methanol (HPLC quality), formic acid (99.9%, LC-MS grade), and acetonitrile (LC-MS grade). Cellulase (T richoderma Vride G, 400 u/mg), hemicellulase (Aspergillus niger, 20 u/mg), and pectinase (Aspergillus niger, 500 u/mg) were obtained from Yuanye Bio-Technology Co., Ltd. (Shanghai, China).

Folin-ciocalteau’s reagent, 2,4,6-Tris(2-pyridyl)-s-triazine (TPTZ), 6-Hydroxy-2,5,7,8-tetramethylchromane-2-carboxylic acid (Trolox) and 43 phenolic compounds’ standards (Eriocitrin, Narirutin, Naringin, Hesperidin, Neohesperidin, Rhoifolin, Diosmin, Quercitrin, Eriodictyol, Didymin, Poncirin, Quercetin, Naringenin, Luteolin, Hesperetin, Kaempferol, Apigenin, Diosmetin, Sinensetin, Nobiletin, Tangeretin, Isosinensetin, 5-O-Demethylnobiletin, Luteoloside, Ferulic acid, Caffeic acid, Chlorogenic acid, Gallic acid, Rutin, Neoeriocitrin, Isosakuranetin, Protocatechuic acid, 4-hydroxy-3-methoxybenzoic acid, p-Hydroxybenzoic acid, p-Coumaric acid, Sinapic acid, 3,5,6,7,8,3′,4′-heptamethoxyflavone, 4′,5,6,7-tetramethylflavone, 4′,5,7,8-tetramethylflavone, Natsudaidain, Epigallocatechin, Isorhamnetin, Myricetin) were acquired from Shanghai Yuanye Bio-Technology Co., Ltd. (Shanghai, China). 2,2-diphenyl-1picrylhydrazyl (DPPH), 2,2′-azino-bis-(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and Gallic acid were obtained from Shanghai Macklin Biochemical Co., Ltd. (Shanghai, China). The rest of the chemicals were all from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). All solvents/chemicals used were analytical or HPLC grade.