linoleic-acid and proanthocyanidin

The antioxidant potential of ethanol extracts from defatted Bokbunja seed wastes generated during wine processing were estimated by radical scavenging abilities (DPPH(*), H(2)O(2), and O(2)(*-)), retardation of lipid oxidation, and iron ion-chelating characteristics. For comparison, ethanol extracts from seeds of fresh ripe Bokbunja fruits were also used. The ethanol extracts from the wine seed waste always showed higher scavenging activities against DPPH(*), H(2)O(2), and O(2)(*-) than those from the fresh seeds. The oxidation of linoleic acid in dimethylsulfoxide at 105 degrees C revealed that the kinetic behavior clearly obeyed pseudo-zero-order regardless of the linoleic acid concentration. The Fe(II)-chelating capacity was determined by the Freundlich isotherm. The results showed high potential and favorability of the two extracts for Fe(II) chelation. The Freundlich chelation capacities (mg(1-1/n)L(1/n)/g) of both ethanol extracts from seeds of fresh Bokbunja and wine processing wastes, tannic acid, and proanthocyanidin from Pinus radiata bark were 100, 224, 260, and 307, respectively. The Fe(III)-chelating properties of the ethanol extracts were considered to be deeply associated with its 3',4',5'-trihydroxyl (galloyl) group as with tannic acid.

Topics: Antioxidants; Biotechnology; Biphenyl Compounds; Chelating Agents; Ethanol; Free Radical Scavengers; Hydrazines; Hydrogen Peroxide; Iron; Linoleic Acid; Lipids; Oxygen; Picrates; Proanthocyanidins; Seeds; Tannins; Wine

Purification of polar fractions from cacao liquor extracts gave 17 phenolics including four new compounds. The new compounds were characterized as a C-glycosidic flavan, an O-glycoside of a dimeric and two O-glycosides of trimeric A-linked proanthocyanidins, on the basis of spectroscopic data. Isolated polyphenols showed inhibitory effects on nicotinamide adenine dinucleotide phosphate-dependent lipid peroxidation in microsomes and on the autoxidation of linoleic acid. These effects were attributed to the radical-scavenging activity in the peroxidation chain reactions, based on the findings that the cacao polyphenols effectively scavenged the 1,1-diphenyl-2-picrylhydrazyl radical.

Topics: Animals; Anthocyanins; Antioxidants; Cacao; Flavonoids; Free Radical Scavengers; Glycosides; Linoleic Acid; Lipid Peroxidation; Microsomes, Liver; Oxidation-Reduction; Phenols; Plant Extracts; Polymers; Proanthocyanidins; Rats