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Updated: Aug 20, 2026

Microwave-Assisted Extraction of Phenolic Compounds and Antioxidants for Cosmetic Applications Using Polyol-Based Technology
Published on: August 23, 2024
Antioxidative activity of a zinc-chelating substance in coffee
Xu Wen1, Makiko Takenaka, Masatsune Murata
1Department of Nutrition and Food Science, Ochanomizu University, Tokyo, Japan.
Abstract:
Coffee brew contains a brownish zinc-chelating polymer designated ApV. ApV was prepared from the precipitate formed in a solution of instant coffee by adding ZnCl(2) and purified using ion-exchange and cellulose column chromatographies. The antioxidative activities of ApV and related compounds were evaluated in this study. The free-radical scavenging activity of ApV estimated by ABTS assay was at a similar level to that of instant coffee, while the O(2)(-) scavenging activity of ApV, which is superoxide dismutase-like activity, was lower than that of instant coffee. The hydroxyl-radical scavenging activity of ApV was higher than that of instant coffee, and the auto-oxidation of linoleic acid was more strongly inhibited by ApV than by caffeic acid.
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