乌珠穆沁羊与小尾寒羊一磷酸腺苷激活蛋白激酶酶活性与肉品质的关系研究

Study on the relationship between adenosine monophosphate-activated protein kinase activity and meat quality in Ujumqin sheep and Small Tailed Han sheep

中文关键词:  乌珠穆沁羊  小尾寒羊  一磷酸腺苷激活蛋白激酶  糖酵解  肉品质

英文关键词:Ujumqin sheep  Small Tailed Han sheep  adenosine monophosphate-activated protein kinase  glycolysis  meat quality

中文摘要:

      目的 研究乌珠穆沁羊与小尾寒羊不同生长阶段、不同部位骨骼肌一磷酸腺苷激活蛋白激酶(adenosine monophosphate-activated protein kinase, AMPK)活性、糖酵解与肉质相关指标的内在变化规律。方法 通过夹心酶联免疫吸附法测定6月龄和8月龄乌珠穆沁羊与小尾寒羊的股二头肌、背最长肌与臂三头肌AMPK活性, 比色法测定乳酸(lactic acid, LA)含量, 微量法测定肌糖原含量和分光光度法测定己糖激酶(hexokinase, HK)含量以及常规法测定肉品质等相关性指标。结果 两个品种的肉羊之间AMPK活性无显著差异(P>0.05); AMPK活性升高, 同时pH24、L*、b*与剪切力降低, 8月龄LA及a*、6月龄肌糖原含量和HK活性升高(P<0.05)。被激活的AMPK能够刺激产能过程糖酵解的HK活性、磷酸果糖激酶和丙酮酸激酶, 酶活性与LA含量呈正相关, 宰后呼吸方式的改变导致pH快速下降, 剪切力与熟肉率增大, 嫩度降低。结论 宰后羊肉AMPK活性与糖酵解和肉品质之间存在一定的相关性。AMPK活性以及糖酵解的程度不同, 可能导致了肉的剪切力、瘦肉率以及嫩度等差异, AMPK活性增强糖酵解的关键酶被激活活性增加, 加快糖酵解进程从而影响肉品质。

英文摘要:

      Objective To investigate the internal changes of adenosine monophosphate-activated protein kinase (AMPK) activity, glycolysis and meat quality of Ujumqin sheep and Small Tailed Han sheep at different growth stages and different parts of skeletal muscles. Methods The activity of AMPK by sandwich enzyme-linked immunosorbent assay, lactic acid (LA) content was measured by micro method, muscle glycogen content was measured by colorimetry, hexokinase (HK) content was measured by spectrophotometry and the correlation indexes of meat quality for were determined by routine method for 6 months and 8 months old indexes from in biceps femoris muscle, longissimus and triceps brachii of Ujimqin sheep and Small Tailed Han sheep. Results Different kinds of lamb had no significant in AMPK activity (P>0.05). The AMPK activity had a significant negative correlation with pH24, L*, b* and shear force, had a significant positive correlation with 8 months LA and a*, and 6 months muscle glycogen content and HK activity (P<0.05). Activated AMPK could stimulate key enzymes for phosphorylated glycolysis with HK activity and phosphofructo kinase and pyruvate kinase, enzyme activity had a significant positive correlation with LA content. The change of breathing pattern after slaughter led to pH and tenderness decreased, shearing force and cooked meat rapidly increased. Conclusion The change of AMPK activity has certain effects on the glycolysis and meat quality. Difference the degree of AMPK activity and glycogen may lead to the difference in shear force, cooked meat and tenderness, after being activated of AMPK activity and glycolytic key enzymes is enhanced, glycolysis process is accelelated and affecting meat quality.