*2.3. Qualitative Analysis of COG-Up®*

COG-up® (a combined extract of *Erigeron annuus* (L.) Pers. and *Brassica oleracea* Var.) was provided by Famenity (Uiwang, Korea). Scutellarin (Glentham, Corsham, UK) standard sample and test sample (COG-up®) were precisely weighed and dissolved. These samples (5 µL, respectively) were subjected to HPLC (Agilent 1260 Infinity II Prime LC System) (Agilent Technologies, Inc., Waldbronn, Germany) using Discovery C18 column (diameter of 4.6 mm, length of 250 mm) (Sigma-Aldrich Co., St. Louis, MO, USA), which was filled with octadecylsilyl silica gel (diameter of 5 µm) at 1.0 mL/min of flow rate. Optimum HPLC separation was achieved at 30 ◦C. UV wavelength was 335 nm for the scutellarin. Phosphoric acid (Junsei Chemical Co., Ltd., Tokyo, Japan) was mixed with distilled water and methanol (JT Baker, Phillipsburg, NJ, USA) which were used as a mobile phase. Mobile phase condition for the scutellarin using A (0.5% phosphoric acid in water) and B (methanol) was as follows: 0–5 min (25% B), 5–25 min (25–55% B), 25–30 min (55–100% B), 30–32 min (100% B), 32–33 min (100–25% B), 33–40 min (25% B).

For high analytical performance, pretreatment using alkaline solvent was required for sinapic acid. Sinapic acid (Sigma-Aldrich Co., St. Louis, MO, USA) standard sample and the test sample (COG-up®) were precisely weighed and dissolved. These samples (5 µL) were subjected to HPLC (Agilent 1260 infinity II, Agilent Technologies, Inc., Santa Clara, CA, USA) using the same column and flow rate. Optimum HPLC separation was achieved at 30 ◦C. UV wavelength was 320 nm for sinapic acid. The mobile phase condition for sinapic acid using the same solution A and B was as follows: 0–15 min (10–30% B), 15–25 min (30% B), 25–26 min (30–50% B), 26–27 min (50–90% B), 27–30 min (90% B), 30–32 min (90–10% B) and 32–37 min (10% B).
