Novel DNPH-based method for determination of protein carbonylation in muscle and meat. (15th April 2016)

• Record Type: Journal Article
• Authors: Soglia, Francesca; Petracci, Massimiliano; Ertbjerg, Per
• Is Part Of: Food chemistry. Volume 197:Part A(2016)
• Page Start: 670
• Page End: 675
• Publication Date: 2016-04-15
• Subjects: Protein oxidation -- Protein carbonyls -- Protein cross-linking -- Protein solubility; Food -- Analysis -- Periodicals; Food -- Composition -- Periodicals; 664
• DOI: 10.1016/j.foodchem.2015.11.038
• Languages: English
• ISSNs: 0308-8146

Abstract

Highlights: A novel DNPH-based method was developed. The novel method increased protein solubility before DNPH labeling. More abundant carbonyl labeling compared to traditional the method was obtained. The novel method labeled more carbonyls in soluble as well as insoluble fractions. Examples of muscle carbonyl levels determined with traditional and novel method. Abstract: Protein oxidation is considered an ongoing deteriorative process during storage of fresh and processed meat. Carbonyl compounds have traditionally been detected spectrophotometrically after derivatization with 2, 4-dinitrophenylhydrazine (DNPH) to form protein-bound hydrazones with absorbance at 370 nm. Here we describe a novel DNPH-based method to quantify protein carbonylation in muscle and meat. The additional steps of the novel method aimed at increasing the protein solubility and inducing protein unfolding before labeling with DNPH. Compared to the traditional method, the new procedure reflected an increased protein carbonylation level measuring overall two to fourfold more carbonyls in muscles from different species as well as in soluble, salt-soluble and insoluble protein fractions. The study suggested that protein unfolding is a more important phenomenon than solubilization for increased DNPH labeling. The novel method resulted in three to fourfold larger carbonyl content determined in chicken, pork and beef (2.8, 3.6 and 3.1 nmol/mg of protein, respectively).