Actomyosin nonbinding cathepsin L in walleye pollock surimi

作者：Hu Yaqin^*; Morioka Katsuji; Itoh Yoshiaki

来源：Journal of Food Biochemistry, 2008, 32(2): 143-152.

DOI：10.1111/j.1745-4514.2008.00173.x

Cathepsin L remained with the actomyosin (AM) fraction which was extracted from walleye pollock surimi after three repeats of washing followed by one cycle of dilution-precipitation. The main peak of cathepsin L separated from the peak of AM by Sepharose 6B gel filtration chromatography. This result suggests that cathepsin L is not associated with AM in AM solution, and the enzyme might have interaction with AM in washed meat. In the presence of 0.3-1.0 M NaCl, the activity of cathepsin L was much higher in acidic condition (pH 5.5). In neutral condition (pH 7.0), the activity of cathepsin L still has about 85% that of at pH 5.5 in 0.6 M NaCl. This indicates that the enzyme contributes to the gel deterioration of surimi even at neutral conditions. The activity of cathepsin L in walleye pollock surimi was not affected by a serine-type protease inhibitor, but was inhibited by a cysteine-type protease inhibitor, suggesting that cathepsin L is not activated by trypsin-type serine protease.

• 出版日期2008-4
• 单位浙江大学