Riboflavin photosensitized oxidation of myoglobin

Juliana M. Grippa; Andressa Zawadzki; Alberto Blak Grossi; Leif Horsfelt Skibsted; Daniel R. Cardoso

doi:10.1021/jf405182f

Riboflavin photosensitized oxidation of myoglobin

Juliana M. Grippa, Andressa Zawadzki, Alberto Blak Grossi, Leif Horsfelt Skibsted, Daniel R. Cardoso

Food Chemistry

6 Citations (Scopus)

Abstract

The reaction of the fresh meat pigment oxymyoglobin, MbFe(II)O₂, and its oxidized form metmyoglobin, MbFe(III), with triplet-state riboflavin involves the pigment protein, which is oxidatively cleaved or dimerized as shown by SDS-PAGE and Western blotting. The overall rate constant for oxidation of MbFe(II)O₂ by ³Rib is (3.0 ± 0.5) × 10 ⁹ L·mol^-1·s^-1 and (3.1 ± 0.4) × 10⁹ L·mol^-1·s^-1 for MbFe(III) in phosphate buffer of pH 7.4 at 25 C as determined by laser flash photolysis. The high rates are rationalized by ground state hydrophobic interactions as detected as static quenching of fluorescence from singlet-excited state riboflavin by myoglobins using time-resolved fluorescence spectroscopy and a Stern-Volmer approach. Binding of riboflavin to MbFe(III) has K_a = (1.2 ± 0.2) × 10⁴ mol·L ^-1 with ΔH = -112 ± 22 kJ·mol^-1 and ΔS = -296 ± 75 J·mol^-1·K^-1. For meat, riboflavin is concluded to be a photosensitizer for protein oxidation but not for discoloration.

Original language	English
Journal	Journal of Agricultural and Food Chemistry
Volume	62
Issue number	5
Pages (from-to)	1153-1158
Number of pages	6
ISSN	0021-8561
DOIs	https://doi.org/10.1021/jf405182f
Publication status	Published - 5 Feb 2014

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@article{bf93ba3fcb8141f2ae3524c005e89e3d,

title = "Riboflavin photosensitized oxidation of myoglobin",

abstract = "The reaction of the fresh meat pigment oxymyoglobin, MbFe(II)O2, and its oxidized form metmyoglobin, MbFe(III), with triplet-state riboflavin involves the pigment protein, which is oxidatively cleaved or dimerized as shown by SDS-PAGE and Western blotting. The overall rate constant for oxidation of MbFe(II)O2 by 3Rib is (3.0 ± 0.5) × 10 9 L·mol-1·s-1 and (3.1 ± 0.4) × 109 L·mol-1·s-1 for MbFe(III) in phosphate buffer of pH 7.4 at 25 C as determined by laser flash photolysis. The high rates are rationalized by ground state hydrophobic interactions as detected as static quenching of fluorescence from singlet-excited state riboflavin by myoglobins using time-resolved fluorescence spectroscopy and a Stern-Volmer approach. Binding of riboflavin to MbFe(III) has Ka = (1.2 ± 0.2) × 104 mol·L -1 with ΔH = -112 ± 22 kJ·mol-1 and ΔS = -296 ± 75 J·mol-1·K-1. For meat, riboflavin is concluded to be a photosensitizer for protein oxidation but not for discoloration.",

author = "Grippa, {Juliana M.} and Andressa Zawadzki and Grossi, {Alberto Blak} and Skibsted, {Leif Horsfelt} and Cardoso, {Daniel R.}",

year = "2014",

month = feb,

day = "5",

doi = "10.1021/jf405182f",

language = "English",

volume = "62",

pages = "1153--1158",

journal = "Journal of Agricultural and Food Chemistry",

issn = "0021-8561",

publisher = "American Chemical Society",

number = "5",

}

TY - JOUR

T1 - Riboflavin photosensitized oxidation of myoglobin

AU - Grippa, Juliana M.

AU - Zawadzki, Andressa

AU - Grossi, Alberto Blak

AU - Skibsted, Leif Horsfelt

AU - Cardoso, Daniel R.

PY - 2014/2/5

Y1 - 2014/2/5

N2 - The reaction of the fresh meat pigment oxymyoglobin, MbFe(II)O2, and its oxidized form metmyoglobin, MbFe(III), with triplet-state riboflavin involves the pigment protein, which is oxidatively cleaved or dimerized as shown by SDS-PAGE and Western blotting. The overall rate constant for oxidation of MbFe(II)O2 by 3Rib is (3.0 ± 0.5) × 10 9 L·mol-1·s-1 and (3.1 ± 0.4) × 109 L·mol-1·s-1 for MbFe(III) in phosphate buffer of pH 7.4 at 25 C as determined by laser flash photolysis. The high rates are rationalized by ground state hydrophobic interactions as detected as static quenching of fluorescence from singlet-excited state riboflavin by myoglobins using time-resolved fluorescence spectroscopy and a Stern-Volmer approach. Binding of riboflavin to MbFe(III) has Ka = (1.2 ± 0.2) × 104 mol·L -1 with ΔH = -112 ± 22 kJ·mol-1 and ΔS = -296 ± 75 J·mol-1·K-1. For meat, riboflavin is concluded to be a photosensitizer for protein oxidation but not for discoloration.

AB - The reaction of the fresh meat pigment oxymyoglobin, MbFe(II)O2, and its oxidized form metmyoglobin, MbFe(III), with triplet-state riboflavin involves the pigment protein, which is oxidatively cleaved or dimerized as shown by SDS-PAGE and Western blotting. The overall rate constant for oxidation of MbFe(II)O2 by 3Rib is (3.0 ± 0.5) × 10 9 L·mol-1·s-1 and (3.1 ± 0.4) × 109 L·mol-1·s-1 for MbFe(III) in phosphate buffer of pH 7.4 at 25 C as determined by laser flash photolysis. The high rates are rationalized by ground state hydrophobic interactions as detected as static quenching of fluorescence from singlet-excited state riboflavin by myoglobins using time-resolved fluorescence spectroscopy and a Stern-Volmer approach. Binding of riboflavin to MbFe(III) has Ka = (1.2 ± 0.2) × 104 mol·L -1 with ΔH = -112 ± 22 kJ·mol-1 and ΔS = -296 ± 75 J·mol-1·K-1. For meat, riboflavin is concluded to be a photosensitizer for protein oxidation but not for discoloration.

U2 - 10.1021/jf405182f

DO - 10.1021/jf405182f

M3 - Journal article

AN - SCOPUS:84893653681

SN - 0021-8561

VL - 62

SP - 1153

EP - 1158

JO - Journal of Agricultural and Food Chemistry

JF - Journal of Agricultural and Food Chemistry

IS - 5

ER -

Riboflavin photosensitized oxidation of myoglobin

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