Tropical Journal of Pharmaceutical Research

Original Research Article | OPEN ACCESS

Extraction and antioxidant activity of phenolic compounds from wheat bran treated by steam explosion

Xueling Zheng, Ruiting Zhang, Chong Liu

College of Grain and Food, Henan University of Technology, Zhengzhou, 450001, PR China;

For correspondence:- Chong Liu Email: liuachong@126.com

Received: 15 May 2015 Accepted: 9 September 2015 Published: 31 October 2015

Citation: Zheng X, Zhang R, Liu C. Extraction and antioxidant activity of phenolic compounds from wheat bran treated by steam explosion. Trop J Pharm Res 2015; 14(10):1857-1863 doi: 10.4314/tjpr.v14i10.17

© 2015 The authors.
This is an Open Access article that uses a funding model which does not charge readers or their institutions for access and distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0) and the Budapest Open Access Initiative (http://www.budapestopenaccessinitiative.org/read), which permit unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited..

Abstract

Purpose: To use response surface methodology to optimize the extraction of the phenolic compounds in wheat bran treated by steam explosion, and to determine the antioxidant activity of the extract obtained.

Methods: By using response surface methodology, the effects of extraction time, methanol concentration, liquid/solid and temperature were studied and optimized. 2,2-Diphenyl-1-(2,4,6-trinitrophenyl) hydrazyl (DPPH) radical-scavenging capacity, reducing capacity and 2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS) radical scavenging capacity were also employed to determine antioxidant activity of the extract.

Results: Under the optimal conditions, i.e., extraction time: 120 s, ethanol content: 43 %, liquid/solid: 35:1, temperature: 70 ^oC, the experimental total phenolic yield was 30.464 ± 0.025, which agreed with the predicted value of 31.687. The phenolic compounds showed strong antioxidant activities. At extract concentration of 1 mg/ml, DPPH radical-scavenging activity was 50 %. Although its reducing power (2 – 10 mg/mL) was lower than that of BHA, ABTS radical scavenging of the extract (close to 90 %) was higher than that of BHA at extract concentration > 6 mg/mL.

Conclusion: The yield of the phenolic compounds was high and the compounds displayed strong antioxidant capacity, which indicates that the extraction of wheat bran under steam explosion holds high potentials for the food and pharmaceutical industries.

Keywords: Wheat bran, Steam explosion, Extraction, Response surface methodology, Antioxidant capacity