A Judgment on Postmortem Aging in<i>Longissimus Dorsi</i>Based on a Peptide Substrate Library
作者:Eiichiro ONITSUKA、Tomoyuki OKUMURA、Hiroshi MURAKAMI、Norikazu NISHINO、Fumiki MORIMATSU
DOI:10.1271/bbb.60208
日期:2006.12.23
We attempted to develop a method to determine easily and effectively the degree of postmortem aging of pork longissimus dorsi (LD) by measuring the activity of proteases in the LD using fluorogenic peptide substrates. LD was used to measure the change with time in the protease activity detected with these substrates. Determining the variations within the LD muscles, strong positive correlations were found between changes in hardness and fluorescence intensities against Ac-Ala-MCA, Ac-Met-MCA, Ac-Ser-MCA, Ac-Thr-MCA, and Ac-Ala-Phe-MCA (P<0.005), and strong negative correlations were found between changes in total amounts of free amino acids and Ac-Ala-MCA, Ac-Met-MCA, Ac-Ser-MCA, Ac-Thr-MCA, and Ac-Ala-Phe-MCA (P<0.001). Negative correlations were also observed between changes in the amounts of free Ala, Arg, Lys, Leu, Met, Phe, and Tyr and the fluorescence intensities against Ala, Arg, Lys, Leu, Met, Phe, and Tyr-MCA respectively (P<0.001).
我们尝试开发一种方法,通过使用荧光底物检测猪背最长肌(LD)中的蛋白酶活性,来简易有效地确定猪背最长肌死后老化的程度。利用这些底物检测到的蛋白酶活性的变化,用于衡量LD肌肉随时间的变化。在确定LD肌肉内的变异时,我们发现硬度的变化与荧光强度之间存在强烈的正相关,这些荧光强度是针对Ac-Ala-MCA、Ac-Met-MCA、Ac-Ser-MCA、Ac-Thr-MCA和Ac-Ala-Phe-MCA的(P<0.005),同时也发现总游离氨基酸量的变化与Ac-Ala-MCA、Ac-Met-MCA、Ac-Ser-MCA、Ac-Thr-MCA和Ac-Ala-Phe-MCA之间存在强烈的负相关(P<0.001)。我们还观察到,游离的Ala、Arg、Lys、Leu、Met、Phe和Tyr的量的变化与针对Ala、Arg、Lys、Leu、Met、Phe和Tyr-MCA的荧光强度之间存在负相关(P<0.001)。