Effects Of ROS Formation On Caspase-mediated Cytoskeleton Protein Of Mutton Sheepafter Slaughter

With the improvement of living standard,people pay more and more attention to the quality of meat.In order to improve the meat quality,this paper test the raw material used in shandong sheep spine,mutton is high protein,low fat,low cholesterol meat quality,has the very high nutritional value,as one of the main categories of sheep breeds,sheep research in shandong province in muscle quality changes and muscle of mature mechanism to improve the quality of the lamb has extremely important practical significance1.In order to study the degradation of myofibrin in sheep slaughtered muscle under natural storage state,the spine meat samples of about 10 g for 0 d were quickly taken,and the remaining meat samples were respectively mature at 4?for 12 h,24 h,36 h,48 h,60 h,72 h,84 h,96 h,120 h,and 144 h before sampling and rapid freezing.The content of reactive oxygen species?ROS?was determined by fluorescence probe analysis,and it was found that the test sites of natural muscle maturation were significantly higher than that of 0 h?p<0.05?.By sds-page method to determine the degree of skeletal muscle and tender meat highly correlated with actin?neb?Lin?,titinand troponin T degradation changes,caspase 3 is analyzed by western blot method,the change of caspase-9 activation fragment expression level,the study found that these proteins are of significant degradation in the process of mature?p<0.05?.The changes of caspase-3 and caspase-9 enzyme activities in different mature stages were analyzed,and it was found that the activity of caspase-3 enzyme was the highest at 72 h,while the activity of Caspase-9 enzyme was relatively low at72 h.2.In order to study the changes of spine quality in different storage periods,basic quality data analysis was conducted.Within 60-72 h,the meat color of mutton changes significantly,its brightness reaches the maximum,its red decreases,and its yellow increases.During the post-slaughter ripening process,the p H of mutton decreased first and then increased,with a significant change in p H between 60-72 h,during which the shear force of mutton gradually increased after 60 h.Myogen fragmentation index?MFI?and volatile base nitrogen?TVB-N?increased with the maturation time.The content of malondialdehyde?MDA?increased with the maturation time,and the MDA reached its maximum at 72 h.The water retention reaches its maximum at 48-60 h.3.Different induction methods?10 mmol/L H₂O₂and NAC?were used to treat the samples,and the mechanism of postmortem muscle maturation of mutton was investigated again.The relative ROS content in the H₂O₂-treated group and NAC treated group was significantly correlated with that in the blank group?p<0.01?,and the ROS content was significantly increased?p<0.05?.The activities of caspase-3and Caspase-9 in the induced group were significantly different from those in the blank group?p<0.01?,with minimum and maximum values at 48 h and 72 h,respectively.Compared with the blank group,the expression fragment of caspase-3and Caspase-9 in the two induced treatment groups showed a darker color,and the color of the expression fragment in the H₂O₂treatment group was generally lighter,with the deepest color at 24-48 h,and the IOD value was significantly higher than that in the blank group?p<0.05?.Compared with the blank group,the expression of troponin-T fragment in the H₂O₂treatment group became darker,and the general color of the NAC treatment groupbecame lighter.Troponin-t IOD in the H₂O₂induction treatment group and the NAC induction treatment group were significantly correlated with troponin-T IOD in the blank group?p<0.01?.The control groupand the control group were compared,in accordance with the statistical difference,it can be seen that the shear stress of blank control group is significantly less than that of NAC group and treatment group.The shear stress is the maximum.and the shear stress reached the maximum at 72h.After H₂O₂and NAC treatment,MFI of sample group and blank group showed significant difference?p<0.05?,and The longer the time,the more obvious the proportion of increase.Relevant data show that the best time to improve mutton quality is 60 to 72 hours,and the corresponding meat quality co?Ld be changed by reg?Lating enzyme activity and expression.It is concluded that 60h is the best time to regulate the mutton quality during the ripening period,when the meat color,shear force and other qualities reach the best,the caspase system is relatively active,and ROS starts to increase significantly after48h.Therefore,this time is suitable for controlling the induction factor to control the mature stage of meat products.