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When myosins prepa•¬ed from the skeletal muscles of seven different fish species and rabbit were incubated with calpain in the low salt solution at various temperatures, a myosin rod-like fragment (Mr= 150,000 protein band on SDS-PAGE) was preferentially formed in all myosins examined and increased proportionally to the cleavage of myosin heavy chain. It was found that rabbit myosin, the most thermally stable of myosins was used, the most stable to proteolysis;

Carp myosin was fluorescently labeled with 1,5 IAEDANS at the SH1 thiol group to enable identification of the head portion of the heavy chain where this group is located. The labeled myosin was heated at 35•KC for 10min to induce thermal denaturation (95% loss of myosin Ca-ATPase activity) or unheated, and then digested by five different proteases (i. e. calpain, a-chymotrypsin, trypsin, papain, and subtilisin) under the same conditions in 0.05m NaCl at neutral pH, respectively. The proteolytic products were analyzed by SDS-PAGE. The digestion of the unheated native myosin showed protease specific fragmentation patterns.

The effects of soybean pectic polysaccharide on cholesterol metabolism in rats were examined. The polysaccharide gradually repressed the increase in the serum cholesterol level; whereas, citrus pectin rapidly repressed the increase and cholesterol accumulation in the liver was not observed. Significanct differences in cecal short-chain fatty acid concentrations were not observedj therefore, further experiments are necessary to clarify the mechanism.