Identification of an antioxidant, ethyl protocatechuate, in peanut seed testa.
The antioxidant activity and identification of the antioxidant component of peanut seed testa were investigated. The antioxidant activity of peanut seed testa was studied in the linoleic acid model system by using the ferric thiocyanate method. Among the five organic solvent extracts, the ethanolic extracts of peanut seed testa (EEPST) produced higher yields and stronger antioxidant activity than other organic solvent extracts. EEPST was separated into 17 fractions on silica gel column chromatography. Fraction 17, which showed the largest yield and significant antioxidant activity, was separated by thin-layer chromatography. Four major antioxidative subfractions were present. Subfraction 17-2 was found to be effective in preventing oxidation of linoleic acid. This subfraction was further fractionated and isolated and characterized by UV, MS, IR, and (1)H NMR techniques. The active compound was identified as ethyl protocatechuate (3,4-dihydroxybenzoic acid ethyl ester).
Huang
Shiow Chyn
SC
Department of Food Health, Chia Nan University of Pharmacy and Science, 60 Erh-Jen Road, Section 1, Pao-An, Jen-te Hsiang, Tainan Hsien, Taiwan, Republic of China.
Yen
Gow-Chin
GC
Chang
Lee-Wen
LW
Yen
Wen-Jye
WJ
Duh
Pin-Der
PD
D000975:Antioxidants / Q000032:analysis*; D010367:Arachis / Q000737:chemistry*; D002855:Chromatography, Thin Layer; D000431:Ethanol; D062385:Hydroxybenzoates / Q000032:analysis*; D010936:Plant Extracts / Q000737:chemistry; D012639:Seeds / Q000737:chemistry*
D000975:Antioxidants; D062385:Hydroxybenzoates; D010936:Plant Extracts; D000431:Ethanol; C018063:ethyl protocatechuate