Bio-Monitoring

Bio-Monitoring of Environmental Pollutions

Specific Areas:

• Water pollution detection
• Biological early warning
• Water Quality Assessment
• Detection of heavy metal pollution

O₂ and H⁺ activities are essential to all organisms, while aquatic organisms seems to be more sensitive than others in response to environmental changes, especially pollutants. So, O₂ and H⁺ fluxes are good and reliable indicators of environmental pollutions.

It can be applied to water quality assessment, biological early warning of environmental pollutions etc.

Examples:

O₂ fluxes changes of fathead embryo in response to different pollutants

Sanchez BC, et al. Oxygen Flux As an Indicator of Physiological Stress in Fathead Minnow (Pimephales promelas) Embryos: A Real-Time Biomonitoring System of Water Quality. Environ. Sci. Technol. 2008, 42: 7010-7017.

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Bioremediation

Heavy metal pollution and its treatments

Specific Use

• Heavy metals pollution monitoring
• Heavy metal enrichment mechanism
• Heavy metals pollution control
• Plant heavy metal tolerance mechanism
• screening of heavy metals highly efficient enrichment plant varieties

Some organisms, especially some plants have developed a mechanism heavy metal tolerance by heavy metal (such as of Cd^2 +) enrichements in their organelle, which provides the possibility for the bioremediation of heavy metal pollution.

Most of the animals, however, are very sensitive to the presence of heavy metals in terms of significant changes of their respirations. Therefore, NMT, which can directly measure Cd²⁺ , H⁺ and O₂ with living samples- is an ideal tool to study the mechanisms of heavy metal absorption and regulations.

Examples:

The intestinal and Malpighi tube play an important role in the chironomid larvae Cd²⁺ transport and absorption process

Leonard EM,et al. Cadmium transport by the gut and Malpighian tubules of Chironomus riparius.  Aquatic Toxicology. 2009, 92: 179-186.

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Bio-Green-Energy

 Bio-Green-Energy

Single-cell, real-time measurements of extracellular oxygen and proton fluxes from Spirogyra grevilleana

NMT is sensitive enough to measure oxygen fluxes around single cells. Porterfield and Smith et al. have characterized oxygen and proton fluxes from a single cell of the filamentous green alga Spirogyra gre illeana (Hass.).

Oxygen showed a net efflux and protons showed a net influx when the cell was illuminated. These photosynthesis-dependent fluxes were found to be spatially associated with the chloroplasts and were sensitive to treatment with dichlorophenyldimethylurea. In the dark the directions of oxygen and proton fuxes were reversed. This oxygen influx was associated with mitochondrial respiration and was reduced by 78% when the cells was treated with 0.5 mM KCN. The residual cyanide-resistant respiration was inhibited by the application of 5 mM salicylhydroxamic acid, an inhibitor of the alternative oxidase. Similarly the cytochrome pathway was also inhibited by the presence of 20 uM NO, while the cyanide-resistant alternative oxidase was not.

These results demonstrate the use of the NMT system to measure and characterize metabolic fluxes at a level of sensitivity that allows for subcellular resolution. 

Phytoremediation

Phytoremediation

Specific Use

• Heavy metals pollution monitoring
• Heavy metal enrichment mechanism
• Heavy metals pollution control
• Plant heavy metal tolerance mechanism
• screening of heavy metals highly efficient enrichment plant varieties

Some organisms, especially some plants have developed a mechanism heavy metal tolerance by heavy metal (such as of Cd^2 +) enrichements in their organelle, which provides the possibility for the bioremediation of heavy metal pollution.

Most of the animals, however, are very sensitive to the presence of heavy metals in terms of significant changes of their respirations. Therefore, NMT, which can directly measure Cd²⁺ , H⁺ and O₂ with living samples- is an ideal tool to study the mechanisms of heavy metal absorption and regulations.

Examples:

Pattern of Cd²⁺ enrichment in wheat roots

Piñeros MA,et al. Development, Characterization, and Application of a Cadmium-Selective Microelectrode for the Measurement of Cadmium Fluxes in Roots of Thlaspi Species and Wheat. Plant Physiology. 1998, 116:1393–1401.

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Microbiology & Food Safety

 Microbiology & Food Safety

• Detect acidification by H⁺ flux and pH in micobe
• Rapidly detect key changes and targets of microbe in food

The ability of certain microbe or yeasts to grow at low ambient pH in the presence of lipophilic weak-acid preservatives inflicts heavy losses on the food and beverage industries. The plasma membrane H⁺-extruding H⁺-ATPase is firmly implicated in the ability of S. cerevisiae to resist intracellular acidification caused by weak organic acids. The effect of long-term benzoic acid exposure on cellular K⁺ of both Z. bailii and S. cerevisiae has been examined as a test of the importance of K⁺ uptake in adaptive growth.                                          

Plasma membrane H⁺ and K⁺ transporters are involved in the weak-acid preservative response of disparate food spoilage yeasts.

Macpherson N, et al. Plasma membrane H⁺ and K⁺ transporters are involved in the weak-acid preservative response of disparate food spoilage yeasts.  Microbiology. 2005, 151(6): 1995-2003.

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