Response of Antioxidant Enzymes and PCs in Root of Neyraudia reynaudiana to Cd, Pb Stress
Neyraudia reynaudiana is one of the most common heavy-metal tolerant plants surrounding mines. Because N. reynaudiana can accumulate large amounts of heavy metals, it could be an effective plant for phytoremediation. In order to study its response to heavy metal stress, a solution culture experiment was carried out at different lead (Pb) and cadmium (Cd) concentrations (0, 25, 50, and 100 μmol·L-1). After 24 hours, oxidative damage, antioxidant enzyme activity, and non-protein thiol compound content or root tissue were assessed. Under Cd and Pb stress, increases in H2O2 and O2?- content were accompanied by malondialdehyde (MDA) content increases. At Pb and Cd concentrations of 100μmol·L-1, the MDA contents respectively reached 6.72 and 16.12 nmol·g-1, and both lipid peroxidation and oxidative damage had increased. Additionally, enzymatic function was effected, with superoxide dismutase (SOD) and peroxidase (POD) activity initially increasing with metal concentration and then declining under higher Pb stress. SOD activity under Cd stress was similar to that under Pb stress, but POD activity was lower. The non-protein thiol content of roots showed that glutathione and phytochelatins initially increased and then decreased with Cd and Pb concentrations. Comprehensive analysis thus revealed that these two heavy metals at different concentrations have different effects on N. reynaudiana root tissue. Overall, N. reynaudiana can adjust its antioxidant enzyme activity and non-protein thiol synthesis levels in order to reduce heavy metal toxicity and damage.
国家科技期刊平台
NSTL
万方数据
维普
