44C-24 |
Estimation of antioxidative activity and safety of methanolic extracts from 'Black Queen' grape seeds and skin |
C. C. YANG, T. C. Wang, and C. S. Lin. Dept. of Food Science, National Ping-Tung University of Science and Technology, Hseuh Fu Road, PING-TUNG , NEI-PU, 912, Taiwan Oxidation of unsaturated lipids initiated by free radicals is a major cause of food quality deterioration and the products of oxidizes lipids are known to impose health risks. We intended to search a new source of antioxidant and wish to discover it is probably usage. Our objectives of this research were to investigate the antioxidative properties of methanolic extracts from Black Queen grape seeds and skin in Taiwan. The investigated items including antioxidative characteristics (by scavenging superoxide anion, hydroxyl radical, hydrogen peroxide, DPPH assay and reducing power test), antioxidative activity in different lipid peroxidation systems (autoxidation, Fe+2, Fe+3, Fe+2/H2O2, and Fe+3/H2O2/ascorbic acid systems), and toxicity and mutagenicity by Ames test. Our results showed that, the antioxidation activity of methanolic extracts of grape seeds (MEGSE) and skin (MEGSK) was lower than butylate hydroxyanisole(BHA), however, stronger than £\-tocopherol. The MEGSE and MEGSK exhibited remarkable antioxidative activity inhibited 90.1% and 75.3% peroxidation of linoleic acid at 400 ppm, respectively. MEGSE and MEGSK showed 88.2% and 75.7% scavenging effect on£\,£\-diphenyl-£]- picryhydrazyl(DPPH) at 100 ppm, respectively. The scavenging effects of MEGSE and MEGSK on superoxide anion were 88.2% and 75.7% at 100ppm, and on hydroxyl radical were 25.3% and 24.2% at 1mg/mL, and on hydrogen peroxide were 40.0% and 38.7% at 1mg/mL, respectively. In addition, the reducing power of MEGSE was higher than 10-fold concentration MEGSK. The MEGSE and MEGSK exhibited the high antioxidative activity in autoxidation system than in other induced systems. The inhibition of peroxidation of MEGSE was better than MEGSK in any peroxidation system. No toxicity and mutagenicity were found in MEGSE and MEGSK by Ames test. The results suggest that both MEGSE and MEGSK have strong antioxidative activity and can passed the microorganism gene toxicology and mutagenic test.
Session 44C, Fruit & Vegetable Products: Chemistry
|