焦磷酸钠对腺嘌呤核苷三磷酸解离氧化肌动球蛋白的影响

Effect of Pyrophosphate on the Dissociation of Natural and Oxidized Actomyosin

研究焦磷酸钠(sodium pyrophosphate,TSPP)对肌动球蛋白的氧化和解离程度,及对腺嘌呤核苷三磷酸(adenosine triphosphate,ATP)解离氧化肌动球蛋白效果的影响。结果表明,TSPP处理能抑制蛋白适度氧化(1 mmol/L H2O2),但氧化程度加深(10、20 mmol/L H2O2)时抑制不明显。TSPP和ATP分别处理时,未氧化肌动球蛋白的特性黏数分别下降了30.4%和41.9%,平均粒径分别下降了21.2%和48.4%。二者相继处理后,特性黏数和平均粒径反而上升。所有氧化样品中由ATP引起的相对黏数变化量几乎都稍高于未氧化样品,但TSPP处理使升高幅度减弱。无论是否经过ATP处理,TSPP样品中均存在未解离且呈纤维状的肌动球蛋白,氧化后形成大的聚集物。可见,TSPP解离效果远不及ATP,且能抑制ATP的解离作用,氧化在一定程度上能促进ATP解离,但受TSPP抑制。研究结果为利用TSPP改善肉制品品质提供了理论依据。

The effect of sodium pyrophosphate(TSPP)on the oxidation and dissociation of actomyosin was investigated together with the influence on the effect of adenosine triphosphate(ATP)in dissociating differently oxidized actomyosin.Results showed that TSPP could inhibit the oxidation of actomyosin by 1 mmol/L H2O2,but have no obvious inhibitory effect on actomyosin oxidation by 10 and 20 mmol/L H2O2.After being treated separately with TSPP and ATP,the intrinsic viscosity of non-oxidized actomyosin decreased by 30.4%and 41.9%,and the average particle size by 21.2%and 48.4%,respectively.After being treated sequentially with TSPP and ATP,the intrinsic viscosity and average particle size of nonoxidized actomyosin increased to some extent.ATP induced a slightly greater change in the relative viscosity of the oxidized samples than that of the nonoxidized samples.However,the increase in the relative viscosity was weakened by TSPP treatment.Undissociated fibrous actomyosin existed in TSPP treated samples with and without ATP treatment,forming large aggregates upon oxidation.In general,TSPP was far less than effective in dissociating actomyosin than ATP,and even it had an inhibitory effect.Oxidation could promote the dissociation of ATP to a certain extent,but this effect was inhibited by TSPP.The results provide a theoretical basis for applying TSPP for improving the quality of meat products.