Biodegradation of Trichloroethylene by Trametes versicolor and its Physiological Response to Contaminant Stress.

Trichloroethylene (TCE) poses a potentially toxic threat to humans and the environment and widely exists in contaminated sites. White rot fungi effectively degrade refractory pollutants, while a few research studies use white rot fungi to degrade TCE. In this study, we investigated TCE biodegradation by white rot fungi and the potential influencing factors in the environment and attempted to research the effect of TCE on the physiological characteristics of white rot fungi. White rot fungi (Trametes versicolor, Pseudotrametes gibbosa, Pycnoporus sanguines and Pleurotus ostreatus) were added to the liquid medium for shock culture. The results revealed that T. versicolor exhibited the most pronounced efficacy in removing TCE, with a degradation rate of 81.10% within a 7 d period. TCE induces and is degraded by cytochrome P450 enzymes. High pH and Cr(VI) adversely affected the effectiveness of the biodegradation of TCE, but the salinity range of 0-1% had less effect on biodegradation. Overall, the effectiveness of degradation of TCE by T. versicolor has been demonstrated, and it provides a reference for the application prospects of white rot fungi in TCE-contaminated soils.

New insights in the biodegradation of high-cyclic polycyclic aromatic hydrocarbons with crude enzymes of Trametes versicolor.

High-cyclic polycyclic aromatic hydrocarbons (PAHs), with complex fused aromatic structures, are widespread, refractory and harmful in soil, but the current remediation technologies for high-cyclic PAHs are often inefficient and costly. This study focused on the biodegradation process of high-cyclic benzo[a]pyrene by Trametes versicolor crude enzymes. The crude enzymes exhibited high laccase activity (22112 U/L) and benzo[a]pyrene degradation efficiency (42.21%) within a short reaction time. Through the actual degradation and degradation kinetics, the degradation efficiency of PAHs decreased with the increase of aromatic rings. And the degradation conditions (temperature, pH, Cu2+ concentration, mediator) were systematically optimised. The optimum degradation conditions (1.5 mM Cu2+, 28℃ and pH 6) showed significant degradation efficiency for the low and medium concentrations of benzo[a]pyrene. In addition, complete degradation of benzo[a]pyrene could be achieved using only 0.2 mM of HBT mediator compared with crude enzymes alone. Collectively, these results showed the high-cyclic PAHs degradation potential of Trametes versicolor crude enzymes, and provided references to evaluate applicable prospects of white rot fungus crude enzymes in PAHs-contaminated soils.

Steering carbon nanotubes to scavenger receptor recognition by nanotube surface chemistry modification partially alleviates NFκB activation and reduces its immunotoxicity.

Carbon nanotubes (CNTs) cause perturbations in immune systems and limit the application of CNTs in biomedicine. Here we demonstrate that a surface chemistry modification on multiwalled CNTs (MWCNTs) reduces their immune perturbations in mice and in macrophages. The modified MWCNTs change their preferred binding pattern from mannose receptor to scavenger receptor. This switch significantly alleviates NFκB activation and reduces immunotoxicity of MWCNTs.

Functionalized carbon nanotubes for potential medicinal applications.

Functionalized carbon nanotubes display unique properties that enable a variety of medicinal applications, including the diagnosis and treatment of cancer, infectious diseases and central nervous system disorders, and applications in tissue engineering. These potential applications are particularly encouraged by their ability to penetrate biological membranes and relatively low toxicity. High aspect ratio, unique optical property and the likeness as small molecule make carbon nanotubes an unusual allotrope of element carbon. After functionalization, carbon nanotubes display potentials for a variety of medicinal applications, including the diagnosis and treatment of cancer, infectious diseases and central nervous system disorders, and applications in tissue engineering. These potential applications are particularly encouraged by their ability to penetrate biological membranes and relatively low toxicity.

[Effects of M-CSF concentration, RANKL concentration and M-CSF preinduction on osteoclastogenesis].

This study was directed to the effects of macrophage-colony stimulating factors (M-CSF) concentration, recerptor activator of nuclear factor kappaB ligand (RANKL) concentration and M-CSF preinduction on osteoclastogenesis and the related resorption function. Bone marrow mononuclear cells were isolated and were divided into 4 groups. Group A underwent osteoclastogenic induction with the use of 30 ng/ml M-CSF and 50 ng/ml RANKL, while Group B received 50 ng/ml M-CSF and 100 ng/ml RANKL treatment. Both C and D Group underwent preinduction with the use of 30 ng/ml M-CSF for 3days, and then they were treated with 30 ng/ml M-CSF and 50 ng/ml RANKL, 50 ng/ml M-CSF and 100 ng/ml RANKL, respectively. Osteoclastogenesis was examined by TRAP staining 6 days after induction, and dentin resorption lacunae were detected by Scanning Electron Microscope 9 days after induction. TRAP positive multinuclear cells were observed in all groups of cells, and resorption lacunae were formed in all of them. However, more TRAP positive multinuclear cells were observed and more large resorption lacunae were detected in groups B and D than in groups A and C, respectively. The number of TRAP positive cells, number of resorption lacunae and lacuna areas in groups C and D were also greater than those in groups A and B, respectively. Higher concentration of M-CSF and RANKL and preinduction with M-CSF may benefit osteoclastogenesis and increase resorption function of osteoclast.