Nonchemical approach for reducing antinutritional factors in rapeseed (Brassica campestris var. Toria) and characterization of enzyme phytase

Antinutritional factors, viz, glucosinolates, phenols, and phytic acid, decreased with germination of rapeseed. Protein content declined during the first 24 h after imbibition and thereafter increased, Phytase activity increased with germination with a parallel decrease in phytic acid content. Two phytase fractions were separated during elution on DEAE-cellulose column, showing purifications of 26.75- and 19.96-fold, respectively. Optimum pH and temperature for both fractions were 5.2 and 50 degrees C, respectively. Enzyme stability decreased considerably after 50 degrees C, and phytase 2 was stable for a longer time. Mn, Co, Ca, and EDTA promoted the enzyme activity, whereas ions of Zn, Fe, Cu, fluoride, molybdate, and arsenate were inhibitory.