title: Effect of heating oxymyoglobin and metmyoglobin on the oxidation of muscle microsomes.
abstract: Myoglobin (Mb) and its iron have been proposed to be major prooxidants in cooked meats. To understand the mechanisms and differentiate between the prooxidant and antioxidant potential of oxymyoglobin (OxyMb) and metmyoglobin (MetMb), their prooxidant activity, iron content, solubility, free radical scavenging activity, and iron binding capacity were determined as a function of thermal processing. The ability of native and heat denatured OxyMb and MetMb to promote the oxidation of muscle microsomes was different. MetMb promoted lipid oxidation in both its native and denatured states. Conversely, OxyMb became antioxidative when the protein was heated to temperatures >or=75 degrees C. The increased antioxidant activity of heat denatured OxyMb was likely due to a decrease in its prooxidative activity due to its loss of solubility. These data show that the impact on oxidative reactions of Mb is the result of the balance between its antioxidant and prooxidant activities.
authors.affiliation: Department of Food Science, University of Massachusetts, Amherst, Massachusetts 01003, USA.
authors.forename: Ricard
authors.initials: R
authors.lastname: Bou
authors.forename: Francesc
authors.initials: F
authors.lastname: Guardiola
authors.forename: Rafael
authors.initials: R
authors.lastname: Codony
authors.forename: Cameron
authors.initials: C
authors.lastname: Faustman
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Elias
authors.forename: Eric A
authors.initials: EA
authors.lastname: Decker
mesh_terms: D000818:Animals; D000975:Antioxidants / Q000737:chemistry; D006358:Hot Temperature; D008786:Metmyoglobin / Q000737:chemistry* / Q000378:metabolism; D008861:Microsomes / Q000737:chemistry* / Q000378:metabolism; D018482:Muscle, Skeletal / Q000737:chemistry* / Q000378:metabolism; D009211:Myoglobin / Q000737:chemistry* / Q000378:metabolism; D010084:Oxidation-Reduction; D013552:Swine
chemical_list: D000975:Antioxidants; D009211:Myoglobin; C017595:oxymyoglobin; D008786:Metmyoglobin