Iron 3 chloride hexahydrate

Silver nitrate (analytical grade, 99.0%) was purchased from Jinchemical Co., Ltd. (Korea). Iron (III) chloride hexahydrate (FeCl₃·6H₂O, 99.0%) and iron (II) chloride tetrahydrate (FeCl₂·4H₂O, 97.0%) were purchased from Junsei Chemical Co. Ltd. (Japan). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) was purchased from Sigma-Aldrich. Sodium borohydride (99.6%) was purchased from TCI Japan. 28% ammonia solution was purchased from OCI Company Ltd. (Korea). Fenugreek seeds (1% moisture content) were procured from local market in India. All chemicals were used as received, without further purification. For the preparation of all solutions, distilled water was used.

The roots of S. miltiorrhiza were purchased in the local market in Seoul, Korea, in June 2017. All solvents for extraction were of Low Particulate grade and purchased from SK Chemicals (Ulsan, Korea). Glucose, gallic acid, quercetin dihydrate, the Folin–Ciocalteu reagent, aluminum chloride, anthrone, sulfuric acid, dimethyl sulfoxide (DMSO), 2,2-diphenyl-1-hydrazyl (DPPH), and 2,4,6-tris(2-pyridyl)-1,3,5-triazine (TPTZ) were purchased from Sigma–Aldrich (St. Louis, MO, USA). Sodium carbonate, potassium acetate, ascorbic acid, and iron (III) chloride hexahydrate were purchased from Junsei Chemical Co., Ltd. (Tokyo, Japan). Methanol was purchased from Burdick & Jackson (Ulsan, Korea). Malt extract broth and brain heart infusion (BHI) were purchased from Difco (Sparks, MD, USA), and tryptic soy broth (TSB) was purchased from MB cell (Seoul, Korea).