PRODUCTION OF PEROXIDASES BY HAIRY ROOTS OF BRASSICA-NAPUS

Hairy roots cultures derived from leaf explants of Brassica napus L. p roduced and secreted peroxidases. The enzyme activity in the medium in creased with growth but it remained nearly constant in the tissue. The changes in extracellular peroxidase activity seemed to be correlated with the increase in a basic peroxidase of pI: 9.6. Four isoenzymes wi th pI in the range 8.5-9.6 and a neutral peroxidase of pI 6.3 were the most important peroxidases detected in cell extracts. Ca2+ addition a t the beginning of the culture stimulated both the excretion of peroxi dase to the medium and the enzyme activity in hairy roots but the isoe nzyme profiles did not show qualitative changes during the growth cycl e for both culture conditions.