Sephadex g 100

The water used in this study was deionized (18 MΩ·cm) from Water Purification System. Sephadex G-100, DEAE-52, 2,2-diphenyl-1-picrylhydrazyl, 2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid, 2,4,6-tri(2-pyridyl)-s-triazine, 6-hydroxy-2,5,7,8-tetramethlchroman-2-carboxylic acid, casein, glacial acetic acid, Tris-base, alcalase, trypsin, papain, neutrase, pepsin, and ammonium persulfate were purchased from Yuanye Biotech Co. Shanghai, China. Absolute ethanol (analytical grade), acetic acid, acetone, ferric chloride, ferrous sulphate, glucose, methanol (analytical grade), perchloric acid, phenol (redistilled reagent grade), potassium per-sulphate, potassium sulphate, sodium acetate, and sodium hydroxide were purchased from DaMao Chemical Co. Tianjin, China. Boric acid, copper sulfate, hydrochloric acid, methylene blue indicator, methyl red indicator, petroleum ether, sulfuric acid, and sodium thiosulfate were purchased from Guangzhou Chemical Co. (Guangzhou, China). Bovine serum albumin, Tris-HCl buffer, SDS, tetramethylethylenediamine were obtained from Sigma Chemical Co. (St. Louis, MO, USA) RIPA lysis buffer, acrylamide/bis-acrylamide mix, ladder protein, were purchased from Thermo Fisher Scientific Co. (Shanghai, China). All other chemicals were of analytical grade.

Polygonatum Cyrtonema were obtained from Xupu County, Hunan Province, China. DEAE-52 cellulose, Sephadex G-100, and different monosaccharide standards (mannose, glucose, galactose, glucuronic acid, and galacturonic acid) were purchased from Yuanye Bio-Technology (Shanghai, China). Different molecular weight dextran was purchased from Aladdin Biochemical Technology Co., Ltd. (Shanghai, China). Acetonitrile was purchased from Sigma-Aldrich (St. Louis, MO, USA). D₂O (D, 99.9%) was purchased from Chemiejoy (Shanghai, China). All other reagents were analytically pure and purchased from Sinopharm Chemical Reagents Co., Ltd. (Shanghai, China).

Sephadex G-100 (purchased from Shanghai Yuanye Bio-Technology Co., Ltd., Shanghai, China) was used to fractionate the purified ACE inhibitory peptides, and distilled water was used as the eluent for elution. Eluted fractions were collected in separate tubes (3 mL/tube) and collected based on peaks. The absorbance of fractions at 280 nm (A_280nm) was measured using an ultraviolet spectrophotometer.