Isolation, Characterization, Antioxidant Activity, Metal-Chelating Activity, and Protein-Precipitating Capacity of Condensed Tannins from Plum (Prunus salicina) Fruit.

ABSTRACT: The type of polymeric condensed tannins from plum fruit (Prunus salicina) (PCT), the degree of polymerization and the distribution of polymers were characterized by MALDI-TOF MS and NMR spectroscopy. The metal-binding capacity of PCT with five metal ions (Cu2+, Zn2+, Al3+, Fe2+, and Fe3+) was characterized by a fluorescence quenching method. The results demonstrated the following: epicatechin was the basic unit occurring in PCT, and A-type and B-type linkages were the most common between the structural units of the polymers. The PCT have a strong antioxidant activity, which is comparable with that of the synthetic antioxidant BHA. The quenching mechanism of the PCT's fluorescence intensity by Zn2+, Cu2+, and Al3+ was different from that of Fe3+ and Fe2+. Fe3+, Al3+ and Fe2+ had much higher

SUBMITTER: Zhang L 

PROVIDER: S-EPMC9030958 | biostudies-literature | 2022 Apr

REPOSITORIES: biostudies-literature