Scavenging Activity of Enzymatic Hydrolysates from Wheat Bran
Jing Wang1*, Xiaoping Yuan2, Baoguo Sun1, Yuan Tian1 and Yanping Cao1
1College of Chemistry and Environment Engineering, Beijing Technology and Business University, 11 Fucheng Road, CN-100037 Beijing, PR China
2Department of Science and Technology, China Grain Reserves Corporation, 143A Xizhimenwai Street, CN-100044 Beijing, PR China
Article history:
Received December 31, 20070
Accepted September 30, 2008
Key words:
antioxidant activity, enzymatic hydrolysates, iron chelation, oxidative stress, wheat bran, xylanases
Summary:
Wheat bran was destarched and deproteinated by α-amylase, protease and amyloglucosidase successively, and further hydrolyzed using Bacillus subtilis xylanases. The yield of enzymatic hydrolysates from wheat bran (EHWB) was 1.84 %. The total phenolics were 0.3712 g of ferulic acid equivalents per gram of EHWB. The antioxidant potency of EHWB was evaluated using different assays, such as iron ion chelation, reducing power, scavenging activity against 2,2’-diphenyl-1-picrylhydrazyl (DPPH) and reactive oxygen species under in vitro conditions. EHWB exhibited an effective ferrous ion chelating activity and strong reducing power. It also showed a high DPPH radical scavenging activity (89.4 %) at 5.0 mg/mL, which was comparable to that of the synthetic antioxidant, butylated hydroxytoluene. EHWB also exerted a marked scavenging effect on ·OH with an EC50 value of 0.46 mg/mL, which was lower than that of mannitol (1.03 mg/mL), a classical hydroxyl radical scavenger, and obvious antioxidant activities toward O2·- and H2O2.
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