苏尼特羊不同部位肌肉抗氧化系统的差异

以放牧条件下的苏尼特羊股二头肌、臂三头肌和背最长肌3个部位的肌肉为材料,测定其丙二醛(MDA)、氧合肌红蛋白(OMb)、高铁肌红蛋白(MMb)含量、抗氧化酶活性(超氧化物歧化酶SOD、过氧化氢酶CAT、谷胱甘肽过氧化物酶GSH-Px)、抗氧化能力(降铜离子还原能力CUPRAC、自由基清除率RSA)、色差和pH值等指标,比较不同部位之间的差异。结果表明:抗氧化酶和抗氧化性能中,臂三头肌的SOD与GSH-Px活性最高,而背最长肌中的CAT活性、CUPRAC和RSA最高。背最长肌的pH值最高,而MDA、L*值、a*值和b*值均显著低于股二头肌和臂三头肌(P<0.05)。股二头肌中OMb显著高于臂三头肌和背最长肌(P<0.05),而MMb显著低于其它部位(P<0.05)。苏尼特羊肌肉中的抗氧化酶之间具有协同作用,且抗氧化酶活力的增强能提高机体抗氧化性能,降低氧化程度。整体上,苏尼特羊背最长肌中抗氧化物质含量较高,脂质氧化程度低于其它两个部位,抗氧化能力较强。

Differences of Muscle Antioxidant System in Different Positions of Sunit Sheep

The malondialdehyde(MDA),oxymyoglobin(OMb),metmyoglobin(MMb),antioxidant enzymes activity(superoxide dismutase SOD;catalase CAT;glutathione peroxidase GSH-Px),antioxidant ability(cupric reducing antioxidant capacity CUPRAC;radical scavenging ability RSA),color and pH were determined to analyze the difference of antioxidant system in biceps femoris muscle(BF),triceps brachii muscle(TB),and longissimus dorsi muscles(LD)from Sunit sheep.The results showed that the SOD and CAT in TB were highest,while the CAT,CUPRAC,RSA in LD was highest.The pH in LD was highest,while the MDA,L*,a*and b*of LD were significantly lower than BF and TB(P<0.05).The content of OMb in BF was significantly higher than TB and LD(P<0.05),while the content of MMb was significantly lower than TB and LD(P<0.05).The antioxidant enzymes in the muscles of Sunit sheep have synergistic effects,and the enhancement of antioxidant enzyme activity will improve the antioxidant ability and reduce the oxidation degree.Overall,the antioxidant substances content,the ability to remove free radicalsin and CAT in LD were highest;lipid oxidation degree was lower than BF and TB.Consequently,the LD has higher antioxidant ability than BF and TB.