Improved solubility and stability of carp myosin by conjugation with alginate oligosaccharide

ABSTRACT:   Carp myosin was conjugated with alginate oligosaccharide (AO) through the Maillard reaction under low relative humidity, and the functional properties of the myosin-AO conjugate were investigated to clarify the role of myosin in the functional improvement of fish myofibrillar proteins (Mf) by the glycosylation. The findings were as follows. First, myosin became highly solubilized at lower NaCl concentrations by conjugation with AO and NaCl-dependence of the solubility was lost when > 12% of the available lysine residues were reacted with AO and 50 µg/mg of AO was attached to myosin. Second, the thermal stability of myosin was effectively improved by conjugation with AO. Heat-treatment at 50°C for 6 h has no effect on the solubility of the myosin-AO conjugate regardless of the NaCl concentration. Third, the improved functionalities of myosin conjugated with AO remained even at a nearly isoelectric point. The improving effect of AO-conjugation on the characteristics of myosin was almost the same as Mf reacted with AO. Therefore, it is apparent that that improved functionalities of the glycosylated Mf reflect the functional changes of myosin.