Lead-resistant strain KQBT-3 inoculants of Tricholoma lobayensis Heim that enhance remediation of lead-contaminated soil.
To enhance lead-detoxifying efficiency of Tricholoma lobayensis Heim, one lead-resistant strain KQBT-3 (Bacillus thuringiensis) was applied owing to its excellent ability to tolerate Pb. KQBT-3 domesticated in liquid medium with increasing lead concentrations could tolerate Pb(NO3)2 up to a concentration of 800 mg L(-1). Pot experiments showed that the KQBT-3 not only could promote the growth of T. lobayensis, but also could enhance its Pb accumulation ability under heavy metal stress. Biomass and accumulation of Pb increased 47.3% and 33.2%, respectively. In addition, after inoculation of KQBT-3, the significant decrease of malondialdehyde indicated KQBT-3 could alleviate lipid peroxidation in T. lobayensis. What is interesting is that superoxide dismutase and peroxidase activities in T. lobayensis inoculated with KQBT-3 were increased, and the maximum increasing rate was 121.71% and 117.29%, respectively. However, the catalase activity increased slightly. This revealed that inoculating KQBT-3 further induced oxidative response in T. lobayensis due to Pb accumulation. Therefore, the present work showed that KQBT-3 made a major contribution to promote growth and lead uptake of T. lobayensis and alleviate the oxidative stress. This kind of auxiliary effect on macrofungi can be developed into a novel bioremediation strategy.
a Key Laboratory of Bio-resources and Eco-environment (Ministry of Education), College of Life Science , Sichuan University , Chengdu , Sichuan , People's Republic of China.
Ying
Y
Li
Chui-Xin
CX
Qin
Biyu
B
Gao
Yuanjia
Y
Hu
Heng
H
Xu
D000975:Antioxidants / Q000378:metabolism; D001413:Bacillus thuringiensis / Q000235:genetics / Q000378:metabolism*; D001673:Biodegradation, Environmental; D004305:Dose-Response Relationship, Drug; D007854:Lead / Q000378:metabolism*; D012988:Soil Microbiology; D012989:Soil Pollutants / Q000378:metabolism*; D055439:Tricholoma / Q000378:metabolism*
D000975:Antioxidants; D012989:Soil Pollutants; D007854:Lead
Tricholoma lobayensis Heim; antioxidative response; bioremediation; lead-contaminated soil; lead-resistant bacteria