Malonaldehyde – induced microestructural modifications in myofibrillar proteins of sea salmon (Pseudopercis semifasciata).

TIRONI, V., LÒPEZ, B.L., PELLEGRINO, N., AÑÓN, M.C., TOMÀS, M.C.

JOURNAL OF FOOD SCIENCE

Año: 2004 vol. 69 p. 519 - 523

0022-1147

ABSTRACT Myofibr rillar  proteins  of sea salmon  were incubated with malonaldehyde (MDA) at 27 °C from 0 to 8 h. M Micr ostructuructural  modifications were investigated by  transmission electronon microscopy. Protein solubility in the presence of sodium dodecyl sulfate (SDS), urea and -mercaptethanol (ME), SDS-polyacrylamide gel elecctrophoresis (PAGE), and available lysine determinations were perfored to analyze the chemical nature of these alterations. Results showed noteworthy microstructural changes and protein aggregation, involving myosin and other myofibrillar proteins. A large proportion of these aggregates was insoluble when treated with SDS, urea, and ME, suggesting the presence of nondisulfide covalent bonds. A reduction in the available lysine content was evidenced because of the reaction of amino groups with MDA.   Keywords: Pseudopercis semifasciata semifasciata, , myofibrillar proteins, malonaldehyde, protein microstructure, avail- available able lysine