Effect of Amino Acids on the State of Water and ATPase Activity Accompanying Dehydration of Fish Myofibrils

Abstract

Changes in the state of water and ATPase activity during dehydration procedures of white croaker myofibrils were investigated in the presence of various amino acids by monitoring the desorption isotherm profile and myofibrillar Ca-ATPase activity. Amino acids were classified into four groups by their effect on myofibrillar Ca-ATPase inactivation; (1) amino acids exerting marked suppressive effect on inactivation such as Na-Glu and Na-Asp, (2) those exerting moderate suppressive effect such as Gly and Ala, (3) those exerting little or no effect on inactivation such as Val, Leu, and Ile, and (4) those accelerating the inactivation including hydrophobic amino acids. The addition of acidic amino acids exhibiting a remarkable suppres-sive effect on ATPase inactivation increased the content of monolayer and multilayer water adsorption of myofibrils.