Vanillic acid

YGMM were provided by Guangxi Hebabiz Pharmaceutical Co., Ltd. (Lot No. 130418). 16 reference standards (purity ≥ 95%) including Z-Ligustilide, senkyunolide H, senkyunolide I, vanillic acid, gallic acid, 3-O-feruloylquinic acid, isochlorogenic acid A, kaempferitrin, mudanpioside D, cassiaside B2, ophiopogonin D, hesperetin, naringin, rutin, quercetin, and ophiopogonanoe B were all purchased from Chengdu Biopurify Phytochemicals Ltd. (Sichuan, China). LC–MS grade acetonitrile and methanol were purchased from Merck (Darmstadt, Germany). LC–MS grade formic acid was obtained from Sigma-Aldrich (Mo, USA). Ultrapure water was purified using a Milli-Q 89 water purification system (Millipore, Billerica, MA, USA). The other reagents were all analytical grade.

Bovine thrombin was obtained from Sigma-Aldrich (Shanghai) Trading Co., Ltd. (Shanghai, China). p-Hydroxybenzoic acid, vanillic acid, naringenin, apigenin, baicalein, catechin, and epicatechin were purchased from Chengdu Biopurify Phytochemicals Ltd. (Chengdu, China). Protocatechuic acid and dihydroquercetin were purchased from Push Bio-Technology Co., Ltd. (Chengdu, China). Gallic acid was the product of Aladdin Reagent Co., Ltd. (Shanghai, China). Tris(hydroxymethyl)aminomethane (Tris) was obtained from Sangon Biotech (Shanghai) Co., Ltd. (Shanghai, China). HCl and acetone were analytical grade reagents and purchased from Chengdu Kelong Chemical Reagent Factory (Chengdu, China).