Interaction between Ellagitannins and Salivary Proline-Rich Proteins

• Type: Article in International Scientific Journal
• Date: 2019

Authors

Susana Soares (Author) FCUP; Brandao, E (Author) Other; Garcia Estevez, I (Author) Other; Fonseca, F (Author) Other; Guerreiro, C (Author) Other; Ferreira da Silva, F (Author) Other; Nuno Mateus (Author) FCUP; Deffieux, D (Author) Other; Quideau, S (Author) Other; Victor de Freitas (Author) FCUP

Journal

Title: Journal of Agricultural and Food Chemistry

Vol. 67

Pages: 9579-9590

ISSN: 0021-8561

Publisher: American Chemical Society

Indexing

ISI Web of Knowledge - 25 Citations

Scopus - 27 Citations

Other information

Authenticus ID: P-00R-1B5

DOI: 10.1021/acs.jafc.9b02574

Abstract (EN): The first contact of tannins with the human body occurs in the mouth, where some of these tannins are known to interact with salivary proteins, in particular with proline-rich proteins (PRPs). These interactions are important at a sensory level, especially for astringency development, but could also affect the biological activities of the tannins. This study gathers information on the relative affinity of the interaction, complex stoichiometry, and tannin molecular epitopes of binding for the interactions between the families of PRPs (bPRPs, gPRPs, and aPRPs) and three representative ellagitannins (castalagin, vescalagin, and punicalagin). These interactions were studied by saturation-tranfer difference NMR and microcalorimetry. The effect of the PRP-ellagitannin interaction on their antioxidant ability was also assessed by ferric reduction antioxidant power (FRAP) assays. The results support a significant interaction between the studied tannins and PRPs with binding affinities in the micromolar range. Punicalagin was always the ellagitannin with higher affinity. aPRPs were the salivary PRPs with higher affinity. Moreover, it was observed that when ellagitannins are present in low concentrations (5-50 mu M), as occurs in food, the antioxidant ability of these tannins when complexed with salivary PRPs could be significantly impaired.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 12