Myricetin

Epimedin C, icariin, icaritin dirhamnoside, baohuoside I, rutin, isoquercitrin, neohesperidin, glucohesperetin, naringin, prunin, myricetrin, myricetin, vitexin, dioscin, zingiberensis newsaponin, ginsenoside Rg2, and ginsenoside Re were all purchased from Sichuan Weikeqi Biotechnology Co., Ltd (China).

The standard compound 2 was a gift from associate professor Peng Wu and the standard compound 4 was obtained from Jie Zhang, Guangzhou University of Chinese Medicine. The other standards were purchased from Sichuan Weikeqi Bio-Technology CO. LTD. (Chengdu, China) and Chengdu Must Bio-Technology Co. Ltd (Chengdu, China). Chemical reagents were obtained from Thermo Fisher Scientific Co. Ltd. (Shanghai, China), and Sigma-Aldrich (St. Louis, MO, USA).

Folin-Ciocalteureagent,gallic acid, catechinand otherpolyphenolicstandardswere purchasedfrom SichuanWeikeqiBiologicalTechnologyCo., Ltd. (China).1,1-Diphenyl-2-picrylhydrazyl(DPPH),2,2’-azinobis(3-ethyl-benzothiazoline-6-sulfonicacid)diammoniumsalt(ABTS),2,4,6-tris(2-pyridyl)-s-triazine(TPTZ),trolox,α-amylase,α-glucosidaseand 4-nitrophenyl-α-D-gluco-pyranoside(α-PNPG)wereobtainedfromSigma–Aldrich(USA).

The total run time was 60 min and the flow rate was constant at 1 mL·min–1. The injection volume of all samples was 20 μL, and the column temperature was maintained at 35°C. The standard product information of the six flavonoids we used can be found on the website of Weikeqi Biotech Co., Ltd. (http://www.weikeqi-biotech.com/). The CAS numbers are: 1. Rutin: 153-18-4; 2. Isoquercetin: 482-35-9; 3. Hyperoside: 482-36-0; 4. Myricetin: 529-44-2; 5. Quercetin-3-O-glucoside: 21637-25-2; 6. Quercetin: 117-39-5.

The reference standards ginkgolide M (3), apigenin-7-O-glucoside (7), bilobalide (8), ginkgolide C (9), quercetin (14), luteolin (15), apigenin (16), kaempferol (17), isorhamnetin (18), ferulic acid (19), ginkgolide A (20), myricetin (22), genistein (23), chlorogenic acid (24), caffeic acid (26), luteolin-7-O-glucoside (33), kaempferol-3-O-glucoside (34), kaempferol-7-O-glucoside (35), quercetin-7-O-rhamnoside (40), isoquercitrin (45) and rutin (65) were purchased from Sichuan Weikeqi Biological Technology Co., Ltd. (Chengdu, China), and their structures are shown in Fig. 1. Purities of all the reference standards were over 98% according to HPLC-DAD analysis.

Daidzein, genistein, myricetin, kaempferide, isorhamnetin, kaempferol, isoquiritigenin and hesperetin (all purities > 98%) were purchased from Weikeqi Biological Technology Co., Ltd. (Sichuan, China). α-CD, β-CD, γ-CD, Me-β-CD, HP-β-CD and SBE-β-CD were purchased from Binzhou Zhiyuan Biotechnology Co., Ltd. (Shandong, China).

Levodopa (l-Dopa, purity ≥ 98%), MgCl2, dithiothreitol (DTT,

purity ≥ 98%), S-adenosyl methionine (SAM), Tris-HCl, and l-adrenaline

was obtained from Sigma-Aldrich (St. Louis, MO). Myricetin, dihydromyricetin, and myricitrin were purchased from from Sichuan Weikeqi

Bio-technology Co. Ltd (Sichuan, China). T