The Development of Innovated Complex Process for Treatment of Old Flotation Tailings of Copper-Zinc Sulfide Ore.

The possibility of selective Cu and Zn leaching from the sample of old pyrite tailings, which is one of the most widespread types of solid waste forming during non-ferrous metal production, using sulfuric acid solutions and water was studied. It was shown that water leaching provided selective extraction of Cu and Zn and comparatively low iron ion extraction. At the same time, acid leaching provided the obtainment of pregnant solutions with high ferric ion concentration, which can be used for oxidative leaching of substandard copper concentrates.

Phytoremediation of toxic chemicals in aquatic environment with special emphasis on duckweed mediated approaches.

The discharge of toxic chemicals into water bodies and their linked detrimental effects on health is a global concern. Phytoremediation, an environment-friendly plant-based technology, has gained intensive interest over the last decades. For the aquatic phytoremediation process, the commonly available duckweeds have recently attracted significant attention due to their capacity to grow in diverse ecological niches, fast growth characteristics, suitable morphology for easy handling of biomass, and capacity to remove and detoxify various potential toxic elements and compounds.

Toxicity of Different Types of Surfactants via Cellular and Enzymatic Assay Systems.

Surfactants have a widespread occurrence, not only as household detergents, but also in their application in industry and medicine. There are numerous bioassays for assessing surfactant toxicity, but investigations of their impact on biological systems at the molecular level are still needed. In this paper, luminous marine bacteria and their coupled NAD(P)H:FMN-oxidoreductase + luciferase (Red + Luc) enzyme system was applied to examine the effects of different types of surfactants, including cationic cetyltrimethylammonium bromide (CTAB), non-ionic polyoxyethylene 20 sorbitan monooleate (Tween 80) and anionic sodium lauryl sulfate (SLS), and to assess whether the Red + Luc enzyme system can be used as a more sensitive indicator of toxicity.

Humic Substances Mitigate the Impact of Tritium on Luminous Marine Bacteria. Involvement of Reactive Oxygen Species.

The paper studies the combined effects of beta-emitting radionuclide tritium and Humic Substances (HS) on the marine unicellular microorganism-luminous bacteria-under conditions of low-dose radiation exposures (<0.04 Gy). Tritium was used as a component of tritiated water.

Effect of external resistance on the sensitivity of microbial fuel cell biosensor for detection of different types of pollutants.

The relatively poor sensitivity is the main bottleneck restricting the application of microbial fuel cell biosensor (MFC-biosensor) for toxicity monitoring. Previous studies have shown that external resistance (R) had an obvious effect on sensor sensitivity. However, these studies reported different results and the reason of this discrepancy was not clear.

Effect of humic substances on toxicity of inorganic oxidizer bioluminescent monitoring.

The current study deals with the effect of humic substances (HS) on toxicity of solutions of a model inorganic oxidizer, potassium ferricyanide. Chemical reactions responsible for toxicity changes are under consideration. The bioluminescent system of coupled enzymatic reactions catalyzed by bacterial luciferase and oxidoreductase was used as a bioassay.

Detoxification of AM-241 solutions by humic substances: bioluminescent monitoring.

The study addresses the effect of humic substances on marine luminous bacteria Photobacterium phosphoreum exposed to Am-241 (3,000 Bq L(-1), water solution). Luminescent intensity of the bacteria was applied as a marker of their physiological activity. Humic substances have been found to reduce the effect of Am-241 on luminescence, decrease damage to cells, and change distribution of Am-241 between bacterial cells and intercellular media.

Bioluminescent monitoring of detoxification processes: activity of humic substances in quinone solutions.

This study deals with application of bioluminescent assay systems to evaluate the detoxifying effect of humic substances (HS) on the solutions of organic oxidizers - quinones. A series of homologous quinones with different redox characteristics: 1,4-benzoquinone, tetrafluoro-1,4-benzoquinone, methyl-1,4-benzoquinone, tetramethyl-1,4-benzoquinone, and 1,4-naphtoquinone, was used. Bioluminescent bacteria Photobacterium phosphoreum, and NADH:FMN-oxidoreductase-luciferase enzyme system isolated from these bacteria were used as assay systems.