Kim Min Young, Yoon Nara, Lee Yoon Jeong, Woo Koan Sik, Kim Hyun Young, Lee Junsoo, Jeong Heon Sang
Department of Southern Area Crop Science, National Institute of Crop Science, Rural Development Administration, Gyeongnam 50424, Korea.
Nongshim Mills, Chungnam 31458, Korea.
Prev Nutr Food Sci. 2020 Sep 30;25(3):310-318. doi: 10.3746/pnf.2020.25.3.310.
The objective of this study was to evaluate the effects of heat treatment on the phenolics and antioxidant activity of rice hull. Heat treatment was performed at temperatures 80∼140°C for 1∼5 h, and the heated rice hull was extracted with 80% (v/v) methanol in an ultrasonic bath. The highest total polyphenol and flavonoid content (10.68 mg gallic acid equivalents/g and 1.83 mg catechin equivalents/g, respectively) occurred in rice hull heated at 130°C for 5 h. During heat treatment, the content of free phenolic acids increased compared with that of the bound phenolic acids. The highest 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity and reducing power was observed in rice hull heated at 140°C for 3 h. The highest OH radical scavenging activity was 75.30% in rice hull heated at 140°C for 5 h. These results suggested that heat treatment was an efficient method to enhance the antioxidant characteristics of rice hull.
本研究的目的是评估热处理对稻壳中酚类物质和抗氧化活性的影响。热处理在80∼140°C的温度下进行1∼5小时，加热后的稻壳在超声浴中用80%（v/v）甲醇提取。总多酚和黄酮含量最高（分别为10.68毫克没食子酸当量/克和1.83毫克儿茶素当量/克）出现在130°C加热5小时的稻壳中。在热处理过程中，游离酚酸的含量相对于结合酚酸有所增加。在140°C加热3小时的稻壳中观察到最高的2,2'-联氮-双-（3-乙基苯并噻唑啉-6-磺酸）自由基清除活性和还原能力。在140°C加热5小时的稻壳中，最高的羟基自由基清除活性为75.30%。这些结果表明，热处理是增强稻壳抗氧化特性的有效方法。
