{"database":"biostudies-literature","file_versions":[],"scores":null,"additional":{"submitter":["Zhang L"],"funding":["National Key Research and Development Program of China","Start-Up Scientific Research Funds for Newly Recruited Talents of Huaqiao Univerisity"],"pagination":["2977"],"full_dataset_link":["https://www.ebi.ac.uk/biostudies/studies/S-EPMC9941574"],"repository":["biostudies-literature"],"omics_type":["Unknown"],"volume":["13(1)"],"pubmed_abstract":["The deprotonation mechanism for the phenolic hydroxyl and the complexing of metal ions with a commonly used food additive, propyl gallate (PG) were studied theoretically and experimentally. The interaction of procyanidins [PC, epicatechin<sub>16</sub> (4 → 8) catechin], and its basic monomeric unit catechin (CA) with metal ions was studied by the fluorescence quenching spectra. The results showed that the 9-OH quinoid PG was formed at higher pH (10.9) by the oxidization of phenolic hydroxyl. The binding affinities (K<sub>a</sub>) and stoichiometry of these metal ions with PG were determined. The Al<sup>3+</sup> in PG-Al complex [Al(PG)(H<sub>2</sub>O)<sub>2</sub>Cl<sub>2</sub>]<sup>-</sup> was coordinated at the 8,9-OH doubly deprotonated catechol site with double chloride ions (Cl<sup>-</sup>) and double water molecules (H<sub>2</sub>O). The fluorescence quenching titration with Sn<sup>2+</sup>, Zn<sup>2+</sup>, Cu<sup>2+</sup>, Al<sup>3+</sup> and Fe<sup>3+</sup> revealed that the stoichiometries of metal-bound PC were 1:1, 2:3, 2:3, 2:3 and 1:1, respectively. The presence of bovine serum albumin (BSA) could enhance the complexing strength of PC with metal ions."],"journal":["Scientific reports"],"pubmed_title":["A spectroscopic and quantum chemical calculation method for the characterisation of metal ions complexed with propyl gallate and procyanidins."],"pmcid":["PMC9941574"],"funding_grant_id":["2022YFD1300903","22BS133"],"pubmed_authors":["Tang L","Xu M","Zhang H","Guan Q","Zhang L"],"additional_accession":[]},"is_claimable":false,"name":"A spectroscopic and quantum chemical calculation method for the characterisation of metal ions complexed with propyl gallate and procyanidins.","description":"The deprotonation mechanism for the phenolic hydroxyl and the complexing of metal ions with a commonly used food additive, propyl gallate (PG) were studied theoretically and experimentally. The interaction of procyanidins [PC, epicatechin<sub>16</sub> (4 → 8) catechin], and its basic monomeric unit catechin (CA) with metal ions was studied by the fluorescence quenching spectra. The results showed that the 9-OH quinoid PG was formed at higher pH (10.9) by the oxidization of phenolic hydroxyl. The binding affinities (K<sub>a</sub>) and stoichiometry of these metal ions with PG were determined. The Al<sup>3+</sup> in PG-Al complex [Al(PG)(H<sub>2</sub>O)<sub>2</sub>Cl<sub>2</sub>]<sup>-</sup> was coordinated at the 8,9-OH doubly deprotonated catechol site with double chloride ions (Cl<sup>-</sup>) and double water molecules (H<sub>2</sub>O). The fluorescence quenching titration with Sn<sup>2+</sup>, Zn<sup>2+</sup>, Cu<sup>2+</sup>, Al<sup>3+</sup> and Fe<sup>3+</sup> revealed that the stoichiometries of metal-bound PC were 1:1, 2:3, 2:3, 2:3 and 1:1, respectively. The presence of bovine serum albumin (BSA) could enhance the complexing strength of PC with metal ions.","dates":{"release":"2023-01-01T00:00:00Z","publication":"2023 Feb","modification":"2025-04-04T13:36:23.432Z","creation":"2025-02-18T22:56:57.038Z"},"accession":"S-EPMC9941574","cross_references":{"pubmed":["36806744"],"doi":["10.1038/s41598-023-30186-x"]}}