We have examined buffer soluble protein content and oxido-reductive and proteolytic enzyme activities of three wheat cultivars with different total protein content. The amount of extracted proteins was lower in wheat with lower total protein content. Activity of glutathione reductase (GR), catalase (CAT), peroxidase (POX) and aspartate protease (phytepsin) was unaffected by differences in total protein content of examined wheat, except in case of peroxidase activity in Srpanjka cultivar. Activity of lypooxigenase (LOX), arginyl and phenylalanyl aminopeptidase (Arg-AP; Phe-AP) was proportionally lower in wheat with lower total protein content. Polyphenoloxidase (PPO) activity was significantly lower, while carboxypeptidase I (CP-I) activity increased with decrease of total protein content. The obtained results indicate that total protein content of wheat affecting the amount of extractable proteins as well as activity of LOX, Arg-AP and Phe-AP, while activities of GR, CAT, POX, PPO, CP-I and phytepsin seem unaffected by total protein content.

oxido-reductive enzymes; proteolytic enzymes; protein content; wheat

Published by University of Zagreb, Faculty of Agriculture, Zagreb, CROATIA
Sponsored by Ministry Science and Education of the Republic of Croatia