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Updated: Jun 10, 2026

A Generalized Method for Determining Free Soluble Phenolic Acid Composition and Antioxidant Capacity of Cereals and Legumes
Published on: June 10, 2022
Oxidative Characteristics of Turkey Hemoglobin A Containing Covalently Bound Epigallocatechin Gallate
Jie Yin1, Wenjing Zhang1, Nantawat Tatiyaborworntham1
1Meat Science and Animal Biologics Discovery, Animal and Dairy Sciences Department, University of Wisconsin-Madison, Madison, Wisconsin 53706, United States.
Abstract:
We investigated the binding of epigallocatechin gallate (EGCG) to turkey hemoglobin A (Hb), noting that polyphenols have the capacity to inhibit oxidative deterioration in muscle foods mediated by endogenous hemoglobin. The addition of EGCG to MetHb resulted in covalently bound EGCG to Cys130 of both α-chains. The crystal structure showed that each bound EGCG was located near the other and in the protein interior. Distances between the nearest phenol/phenolate of bound EGCG and the nearest iron atom of the heme moieties were 11.7-16.5 Å. Antioxidative characteristics due to bound EGCG included decreases in both hemin dissociation and H2O2-mediated ferryl Hb formation, counterbalanced by increased Hb autoxidation. Bound EGCG less effectively inhibited oxyHb-mediated lipid oxidation compared to MetHb-mediated lipid oxidation. The mechanisms by which EGCG adduction affected oxidative characteristics of Hb are discussed, including electron transfer from bound EGCG to the heme, interactions with lipids, and effects of cross-linking on hemin affinity.
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