Effect of Oxidation on In Vitro Digestibility of Skeletal Muscle Myofibrillar Proteins

Abstract

The objective of this study was to investigate the effect of chemical oxidation on myofibrillar protein digestibility. Myofibrils were prepared from pig M. longissimus dorsi and oxidized by a hydroxyl radical generating system. Oxidative modifications of proteins were assessed by the carbonyl content, surface hydrophobicity, electrophoresis, and immunoblotting. Oxidized or nonoxidized myofibrillar proteins were then exposed to proteases of the digestive tract (pepsin, trypsin, and alpha-chymotrypsin). Results showed a direct and quantitative relationship between protein damages by hydroxyl radical and loss of protein digestibility.

Effects of composition and oxidation of proteins on their solubility, aggregation and proteolytic susceptibility during processing of Cantonese sausage

“…The amount of carbonyl groups significantly increased (p < 0.05) from 1.04 to 4.68, 1.32 to 7.00, 1.73 to 2.75 and 1.46 to 3.31 nmol/mg protein in sarcoplasmic, myofibrillar, alkali-soluble and total proteins, respectively. The values at 0th h were close to those reported on chicken myosin (Liu & Xiong, 2000) and pork myofibrils (Santé-Lhoutellier et al, 2007). These changes were similar to those of liver pâté (Estévez & Cava, 2004) and frankfurters (Estévez et al, 2007).…”

“…For example, increase of surface hydrophobicity has been described to facilitate protein degradation by proteases, whereas inter-molecular cross-linking and formation of aggregates under highly oxidative conditions can reduce protein susceptibility against enzymatic hydrolysis (Grune, Jung, Merker, & Davies, 2004). Amino acid oxidation, protein aggregation and the interaction between protein oxidation and proteolysis have been reported in meat (Morzel, Gatellier, Sayd, Renerre, & Laville, 2006;Santé-Lhoutellier, Aubry, & Gatellier, 2007). Protein oxidation in liver pâtés and frankfurters has been suggested to have a close relationship with lipid oxidation (Estévez & Cava, 2004;Estévez et al, 2007).…”

Mass transfer dynamics during brining of rabbit meat

“…Myofibril proteins surface hydrophobicity was investigated by the hydrophobic chromophore bromophenol blue (BPB) method according to Sante-Lhoutellier et al (2007), with slight modifications, as described later. Myofibril proteins were diluted to 5 mg/mL with 20 mM phosphate buffer at pH 7.0.…”

The Effect of Selected Factors on Sensory Quality of Pork

“…Yet it also induces the formation of several carcinogenic heterocyclic amines. High heated proteins could also cause aggregation which has an influence on protein digestion and their nutritional value [41,42].…”