Effect of far-infrared radiation on the antioxidant activity of rice hulls.
After far-infrared (FIR) radiation onto rice hull, a methanolic extract was prepared for the determination of antioxidant ability. After 30 min of FIR treatment, the radical scavenging activity and total phenol contents of rice hull extracts increased from 47.74 to 79.63% and from 0.12 to 0.19 mM, respectively, compared to control. Inhibition of lipid peroxidation in extracts was also increased from 41.07 to 47.96%. According to the GC-MS analysis, more phenolic compounds (p-coumaric acid, 3-vinyl-1-oxybenzene, p-hydroxybenzaldehyde, vanillin, p-hydroxybenzoic acid, and 4,7-dihydroxyvanillic acid) were detected in FIR-irradiated rice hull extract. These results indicated that FIR radiation onto rice hull could liberate and activate covalently bound phenolic compounds that have antioxidant activities.
Lee
Seung-Cheol
SC
Visiting Scholar, Iowa State University, Ames, Iowa 50011-3150, USA. sclee@kyungnam.ac.kr
Kim
Jeong-Han
JH
Jeong
Seok-Moon
SM
Kim
Dong-Ryul
DR
Ha
Jung-Uk
JU
Nam
K C
KC
Ahn
D U
DU
D000975:Antioxidants / Q000032:analysis* / Q000494:pharmacology; D016166:Free Radical Scavengers / Q000032:analysis; D008401:Gas Chromatography-Mass Spectrometry; D007259:Infrared Rays; D015227:Lipid Peroxidation / Q000187:drug effects; D012275:Oryza / Q000737:chemistry*; D010636:Phenols / Q000032:analysis; D010936:Plant Extracts / Q000737:chemistry; D012639:Seeds / Q000737:chemistry*
D000975:Antioxidants; D016166:Free Radical Scavengers; D010636:Phenols; D010936:Plant Extracts