Cynaroside

Chlorogenic acid, isoorientin, and apigenin were purchased from Shanghai Natural Biological Technology Co., Ltd. (Shanghai, China). Iso-vitexin, cynaroside, and luteolin were obtained from Shanghai Yuanye Biological Technology Co., Ltd. (Shanghai, China). Orientin was bought from Chengdu Push Biological Technology Co., Ltd. (Chengdu, China). The purity of all standards was more than 98%, and their chemical structures are listed in Figure 5. DPPH was gained from Sigma-Aldrich (St. Louis, MO, USA). Trolox was from Beyotime Institute of Biotechnology Co., Ltd. (Shanghai, China). Ascorbic acid (VC) was ordered from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). Diamonsil Plus C18 column (4.6 × 250 mm, 5 µm) was used. All liquid chromatography solvents (methanol, acetonitrile) were of HPLC grade, obtained from Anhui Fulltime Specialized Solvent and Reagent Co., Ltd. (Anqing, China), and used after filtration by a 0.45 µm organic membrane. All other solvents were of analytical grade and used without further purification.

Echinatin, Aloeemodin, Loureirin B, Cardamonin, Cynaroside, Artemetin, Neosperidin dihydrochalcone, Hesperetin, and Vitexin used in the study were obtained from Shanghai Yuanye Bio-Technology Co., Ltd. (Shanghai, China). Phloretin was purchased from Macklin Inc. (Shanghai, China). Scutellarin and Acacetin were obtained from MCE (Shanghai, China). Gentisin was obtained from ChemFaces (Wuhan, China). Dimethylsulfoxide (DMSO, Sigma) was used to dissolve all compounds to the concentration of 40 mM.