1 1 diphenyl 2 picrylhydrazyl

Aspergillus niger HS-5 with high enzyme yield was screened by selective medium and compared its β-glucanase activity. The preparation and isolation of A. niger HS-5 β-glucanase was performed in house by using microbial fermentation. In brief, after fermentation, the cells in the fermented broth were removed by centrifugation to obtained crude enzyme solution, then ammonium sulfate salting out method was used to concentrate and Sephadex G-100 chromatography column was used for further purification.
Poria cocos were purchased from the Jiuzihe brand (Huanggang, China). Sulfuric acid, phenol, citric acid, sodium citrate, glucose, sodium dihydrogen phosphate, potassium ferricyanide, ferric chloride, trichloroacetic acid, 1,1-diphenyl-2-picryl-hydrazyl (DPPH), anhydrous ethanol, hydrochloric acid, trometamol, pyrogallic acid, salicylic acid, 1,10-phenanthroline, potassium dihydrogen phosphate, dipotassium hydrogenphosphate, sodium chloride, ferrous sulfate, and hydrogen peroxide (30%) were purchased from Sinopharm Chemical Reagent Co., Ltd. (Shanghai, China). All reagents were of analytical grade.

Corn silk was gathered in the Fushun suburbs, Liaoning Province, China. Sigma Chemicals Co. (St. Louis, MO, United States) provided ascorbic acid, D-galactose (D-gal), and 1,1-diphenyl-2-picrylhydrazyl (DPPH) and Sinopharm Chemical Regent Co., Ltd., Shanghai, China, furnished the rest of the reagents and solvents. All compounds used were analytical grade unless otherwise specified.

Ajuga ciliata Bunge was purchased from the local market in Huangshan City. After being dried for 80 h at 41 °C in a hot air oven, the dried Ajuga ciliata Bunge was ground and conceded through a 100-mesh sieve, sealed in plastic bottle, and stored in the refrigerator at 4 °C. 1,1-Diphenyl-2-picryl-hydrazyl (DPPH), Tris (hydroxymethyl)methyl aminomethane (THAM), ascorbic acid (Vc), salicylic acid (SAA), Gallic acid, phenanthroline, CH₃CH₂OH, ethanol, FeSO₄, Na₂HPO₄, NaH₂PO₄, Li₂SO₄, Na₂MoO₄, Na₂WO₄, HCl, H₃PO₄, Na₂CO₃, H₂O₂ and Br₂ were of analytical grade and purchased from the Sinopharm Chemical Reagent Co. Ltd, China.