title: Crude lipoxygenase from pig muscle: partial characterization and interactions of temperature, NaCl and pH on its activity.
abstract: Crude lipoxygenase (LOX) was extracted from fresh pig bacon belly and studied of partial characteristics. The interactions of temperature, sodium chloride (NaCl) and pH on LOX activity were investigated by response surface methodology (RSM). Kinetic studies indicated that the Michaelis constant (K(m)) and maximum velocity (V(max)) for LOX activity using linoleic acid as substrate were 68 μM and 0.26 U/min at 20°C, respectively. The optimal conditions for this reaction were: substrate concentration 3.47 mM, reaction temperature 39°C and pH ≧9.0. The NaCl critical value for LOX activity was 3.0% (w/w) at 20°C, above which the LOX activity began to decrease. Temperature had significant interactions (p<0.05) with NaCl and pH. The temperature critical value decreased with NaCl content increasing, while increased with pH increasing. These indicated that LOX activity and enzyme-catalyzed lipid oxidation in dry-cured meat products could be regulated by controlling process factors during the processing.
authors.affiliation: National Center of Meat Quality & Safety Control, Nanjing Agricultural University, Nanjing 210095, PR China.
authors.forename: Guofeng
authors.initials: G
authors.lastname: Jin
authors.forename: Jianhao
authors.initials: J
authors.lastname: Zhang
authors.forename: Xiang
authors.initials: X
authors.lastname: Yu
authors.forename: Yanxiong
authors.initials: Y
authors.lastname: Lei
authors.forename: Jiamei
authors.initials: J
authors.lastname: Wang
mesh_terms: D000009:Abdominal Muscles / Q000201:enzymology*; D000818:Animals; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D019787:Linoleic Acid / Q000378:metabolism; D008084:Lipoxygenase / Q000302:isolation & purification / Q000378:metabolism*; D015233:Models, Statistical; D009124:Muscle Proteins / Q000302:isolation & purification / Q000378:metabolism*; D009994:Osmolar Concentration; D012965:Sodium Chloride; D034421:Sus scrofa / Q000378:metabolism*; D013696:Temperature
chemical_list: D009124:Muscle Proteins; D012965:Sodium Chloride; D019787:Linoleic Acid; D008084:Lipoxygenase