*2.2. Chemicals*

The compounds 2,2-diphenyl-1-picrylhydrazyl, 2,2--azobis-(2-amidinopropane) dihydrochloride, 2,2--azino-bis (3-ethylbenzothiazoline-6-sulphonic acid), Folin–Ciocalteu reagent, carbazole, galacturonic acid, gallic acid, and catechin were purchased from Sigma-Aldrich (St. Louis, MO, USA). Phosphate-bu ffered saline (PBS) was purchased from Welgene (Gyeongsan, Korea). Ascorbic acid was purchased from Reagent Duksan (Ansan-si, Republic of Korea). HPLC ginsenoside standards were purchased from Ambo Institute (Daejeon, Republic of Korea).
