Cadmium-induced Membrane Lipid Peroxidation and Changes in Antioxidant Enzyme Activities and Peroxidase Isoforms in Jerusalem Artichoke Seedlings
Jerusalem artichoke (Helianthus tuberosus L.)seedlings cultured in sandy media were treated with Hoagland nutrition solution with different concentrations of Cd(NO3)2 from 0 to 400 μmol/L. After 50 days' treatment, Cd accumulation, activities of peroxidase (POD, EC 1.11.1.7), superoxide dismutase (SOD, EC 1.15.1.1), catalase (CAT, EC 1.11.1.6) were measured and electrophoretograms of POD isoenzymes were analyzed. The accumulation of Cd in seedlings increased from Cd 50-100 μmol/L, after which further increases in Cd concentration resulted in only small increases in accumulation of Cd in seedlings. MDA content was markedly higher than control values indicating the enhanced membrane lipid peroxidation in roots and leaves. POD activities in leaf and root extracts increased with an increase of Cd concentration from 0 to 50 and 100 μmol/L and then decreased with further increases to 200 and 400 μmol/L. Under moderate Cd level of 50-200 μmol/L,SOD activities in leaf and root extracts increased whereas with a higher Cd level of 400 μmol/L marked inhibitions in enzyme activities were observed. With increase in Cd concentration marked elevations in CAT activities in leaves and roots were observed. Results of electrophoresis show that the alteration of POD isoenzyme was noticeable to Cd and an additional POD isoenzyme LP10 appeared. It is suggested that POD isoenzyme of Jerusalem artichoke seedlings could be used as bioindicator for soil contamination by Cd.
NETL
NSTL
万方数据
维普
