Schisandrin

Mushroom tyrosinase, chlorogenic acid, epicatechin, schisandrin, and sodium phosphate monobasic were purchased from Sigma-Aldrich (St. Louis, MO, USA). L-3,4-Dihydroxyphenylalanine (L-dopa) and kojic acid were purchased from Acros (New Jersey, USA). Acetonitrile was purchased from Aencore (Surrey Hills, Australia). Sodium phosphate dibasic anhydrous was purchased from J. T. Baker (Petaling Jaya, Selangor, Malaysia). Methanol was purchased from Merck (Darmstadt, Germany). RVLE (Elastvein®) was purchased from Healthmate (Changhua, Taiwan). Acetic acid was purchased from Panreac (Barcelona, Spain), and gallic acid was purchased from Alfa Aesar (Ward Hill, MA, USA). Rutin was purchased from Extrasynthese (Genay, France). Resveratrol was purchased from TCI (Tokyo, Japan).

Standards of loganin (Lot No. 36483), echinacoside (Lot No. 07538), Verbascoside (Lot No. V4015), Erianin (Lot No. PHL83499), Cinnamic Acid (Lot No. C80857), Tenuifolin (Lot No. PHL83546), Quercetin (Lot No. PHR1488), Ruscogenin (Lot No. SMB00295), Kaempferol (Lot No. 60010), Beta-sitosterol (Lot No. S1270), and Schisandrin (Lot No. SML0054) were purchased from Sigma-Aldrich Co. LLC (St. Louis, MO, United States). Formic acid, methanol, ammonium acetate, ammonium hydroxide, and acetonitrile used in UPLC were provided by Fisher Scientific Co. LLC (Fair Lawn, NJ, United States). The ultrapure water (18.2 MΩ⋅cm) used in the experiment was prepared with Milli-Q IQ 7003 purified water system (Merck Millipore, Darmstadt, Germany).