Tilapia was used as material to extract myosin. The effects of heat
treatment (40-80 ℃, 1℃/min) on the
turbidity, solubility, surface hydrophobicity, α-helix contentand aggregated
particles of myosin were investigated underdifferent ionic strength
(1,50,150,300,600 mmol/KCl).The results showed that the ionic strength and heat
treatment significantly affected the thermal denaturation and aggregation of
myosin. Myosin has poor solubility because of it assembles and forms a
filamentous polymer under low ionic strength (1-150 mmol/L KCl), after heat
treatment, the molecular aggregation precipitates, the solubility and α-helix
content decreased (p<0.05), the
thermal stability of the myosin in this system was undesirable. Whileunder the high
ionic strength (300-600mmol/L KCl), myosin dissociated into monomer,the
solution is clear.When the temperature is higher than 50 ℃, a increase in turbidity and decrease in solubility
of tilapia myosin was detected, accompanied by increasing in surface
hydrophobicity and a significant loss of α-helix (p<0.05), but the molecular aggregation is not obvious.The
results indicated that the electrostatic shielding of high salt ions inhibited formation
of myosin filament, which also protects the molecular structure of myosin.So
that the myosin that under the high ionic strength has better stability.