Affiliations: Department of Food Science, Graduate School of
Nutrition and Biosciences, The University of Tokushima, Kuramoto-cho 3,
Tokushima 770-8503, Japan. Tel.: +81 88 633 7087; Fax: +81 88 633 7089;
E-mail: terao@nutr.med.tokushima-u.ac.jp | Industrial Technology Institute, Miyagi Prefectural
Government 2-2, Akedohri, Izumi-ku, Sendai, Miyagi 981-3206, Japan
Note: [] Corresponding author
Abstract: Vegetables are generally recognized as rich sources of dietary
antioxidants for inhibiting lipid peroxidation. Here we investigated lipid
hydroperoxide (LOOH)-reducing activity of several vegetables to estimate their
role on the prevention of lipid peroxidation in food and the digestive tract.
By using HPLC analysis, we screened vegetables possessing the ability to
convert 13-hydroperoxyoctadecadienoic acid (13-HPODE) to its reduced
derivative, 13-hydroxyoctadecadienoic acid (13-HODE). Welsh onion (Allium
fistulosum L.) was found to be highly active in the reduction of 13-HPODE
among tested vegetables. There was no relationship between 13-HPODE reducing
activity and GSH peroxidase (GPX) activity in the tested vegetables.
13-HPODE-reducing activity of welsh onion was enhanced by the addition of
sulfhydryl compounds including glutathione (GSH). Neither GPX inhibitor nor
heat treatment suppressed 13-HPODE-reducing activity effectively. These results
suggest that welsh onion and other vegetables contain GPX mimics responsible
for the reduction of LOOH. GPX mimics may be helpful in the attenuation of
harmful effect of LOOH from food.
