镉、铅胁迫下长根菇菌丝体中巯基化合物和抗氧化酶系统的变化研究

Explore the changes of thiol compounds and antioxidant enzymes in Oudemansiella radicata mycelium under cadmium and lead stresses

研究了固体培养基中不同浓度水平的镉(Cd)和铅(Pb)胁迫对长根菇菌丝体巯基化合物和抗氧化酶系统的变化.结果表明:高浓度的Cd和Pb显著降低了菌丝体中可溶性蛋白含量,高浓度的镉使得长根菇菌丝体中的巯基化合物含量明显降低,与此同时,长根菇菌丝体中超氧化物歧化酶(SOD)随Pb浓度的增加先上升后下降,过氧化物酶(POD)和过氧化氢酶(CAT)活性在高浓度的Pb胁迫下活性增强,在Cd胁迫下,随着处理浓度的增加,长根菇菌丝体中SOD和CAT的活性也是先上升后下降,而POD的活性变化不明显.说明在低浓度时的重金属胁迫长根菇菌丝体的细胞是有一定的耐受能力的,当随着浓度的增加菌丝体将受到不可逆的损伤.

The impact of different level of cadmium and lead （nitrate salts） stresses to the changes of the thiol compounds and the activities of antioxidant enzymes system were investigated. The results showed that high-level Cd and Pb concentrations significantly decrease the contents of soluble protein, high-level Cd significantly decrease thiol compounds in the Oudernansiella radicata mycelium, while the SOD in the mycelium increased initially and then declined with the increasing of Pb concentration, the POD and the CAT activities were enhanced after exposure to high-level Pb . The activities of SOD and CAT also increased initially and then declined with the increasing of Cd concentration. It indicated that when the concentration of the metal is low-level, the cell can repair itself, but when the metal concentration is high it would cause irreversible damage.