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Team:UCL/Project/About
From 2014.igem.org
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Since their accidental discovery by Sir William Henry Perkin in 1853, azo dyes have become one of the most popular forms of <a data-tip="true" class="top large" data-tip-content="Azo dyes can supply a complete rainbow of colours, but yellow/red dyes are more common than blue/brown dyes." href="javascript:void(0)"><b>synthetic colourant</b></a>. These dyes are currently used in the industrial manufacture of a variety of <a data-tip="true" class="top large" data-tip-content="Azo dyes account for approximately 60-70% of all dyes used in food and textile manufacture." href="javascript:void(0)"><b>products</b></a>, ranging from clothing and upholstery to cosmetics and tattoo ink, as well as many others.<br><br>Although azo-dyes are widely regarded as a safe and stable form of synthetic colourant, some of them can take on <a data-tip="true" class="top large" data-tip-content="Some azo dyes have been reported to cause human bladder cancer, splenic sarcomas and hepatocarcinomas as a result of azo dye reduction in the intestinal tract." href="javascript:void(0)"><b>dangerous properties</b></a> after they have been broken down by <a data-tip="true" class="top large" data-tip-content="The process of azo bond reduction is catalyzed by soluble cytoplasmic enzymes known as azoreductases." href="javascript:void(0)"><b>enzymes</b></a> in the guts of organisms.</p> | Since their accidental discovery by Sir William Henry Perkin in 1853, azo dyes have become one of the most popular forms of <a data-tip="true" class="top large" data-tip-content="Azo dyes can supply a complete rainbow of colours, but yellow/red dyes are more common than blue/brown dyes." href="javascript:void(0)"><b>synthetic colourant</b></a>. These dyes are currently used in the industrial manufacture of a variety of <a data-tip="true" class="top large" data-tip-content="Azo dyes account for approximately 60-70% of all dyes used in food and textile manufacture." href="javascript:void(0)"><b>products</b></a>, ranging from clothing and upholstery to cosmetics and tattoo ink, as well as many others.<br><br>Although azo-dyes are widely regarded as a safe and stable form of synthetic colourant, some of them can take on <a data-tip="true" class="top large" data-tip-content="Some azo dyes have been reported to cause human bladder cancer, splenic sarcomas and hepatocarcinomas as a result of azo dye reduction in the intestinal tract." href="javascript:void(0)"><b>dangerous properties</b></a> after they have been broken down by <a data-tip="true" class="top large" data-tip-content="The process of azo bond reduction is catalyzed by soluble cytoplasmic enzymes known as azoreductases." href="javascript:void(0)"><b>enzymes</b></a> in the guts of organisms.</p> | ||
| - | <p class="infoBlock2 cf" data-step=" | + | <p class="infoBlock2 cf" data-step="3" data-position='top' data-intro="Azo dyes present huge environmental challenges, here we outline the key impacts of azo dyes entering our environment."> |
<a data-tip="true" class="top large" data-tip-content="Exposure of fish (common carp) to dye containing effluent strongly affects their rate of feeding, absorption and conversion (Roopadevi and Somashkar, 2012)." href="javascript:void(0)" style="width: 50%;float: right;margin-left:2%"><img src="https://static.igem.org/mediawiki/2014/6/68/Theproblem.jpg" style="max-width: 100%;"></a>In the textile industry alone, the global annual production of dyes amounts to a <a data-tip="true" class="top large" data-tip-content="Azo dyes represent about 70% of this value on weight basis (Hao et al. 2000)" href="javascript:void(0)"><b>million metric tons</b></a>. In many countries, the leftover dye <a data-tip="true" class="top large" data-tip-content="It had been estimated that about 10-15% of the dye-stuff used during the dyeing process do not bind to fibers and are released in the effluent." href="javascript:void(0)"><b>effluent</b></a> produced by industrial manufacturers is often not properly disposed of, or removed, during water treatment. | <a data-tip="true" class="top large" data-tip-content="Exposure of fish (common carp) to dye containing effluent strongly affects their rate of feeding, absorption and conversion (Roopadevi and Somashkar, 2012)." href="javascript:void(0)" style="width: 50%;float: right;margin-left:2%"><img src="https://static.igem.org/mediawiki/2014/6/68/Theproblem.jpg" style="max-width: 100%;"></a>In the textile industry alone, the global annual production of dyes amounts to a <a data-tip="true" class="top large" data-tip-content="Azo dyes represent about 70% of this value on weight basis (Hao et al. 2000)" href="javascript:void(0)"><b>million metric tons</b></a>. In many countries, the leftover dye <a data-tip="true" class="top large" data-tip-content="It had been estimated that about 10-15% of the dye-stuff used during the dyeing process do not bind to fibers and are released in the effluent." href="javascript:void(0)"><b>effluent</b></a> produced by industrial manufacturers is often not properly disposed of, or removed, during water treatment. | ||
<br><br>This results in the <a data-tip="true" class="top large" data-tip-content="These compounds are designed to be stable against chemical and light induced oxidation, becoming highly persistent in nature. For instance, the half life of reactive blue 19 is about 46 years at pH 7 at 25ºC (Hao et al. 2000)." href="javascript:void(0)"><b>accumulation</b></a> of azo dyes in water bodies where they are then ingested by aquatic organisms. Additionally, irrigation of agricultural lands with dye polluted water severely affects soil fertility and <a data-tip="true" class="top large" data-tip-content="It affects different plant growth parameters namely | <br><br>This results in the <a data-tip="true" class="top large" data-tip-content="These compounds are designed to be stable against chemical and light induced oxidation, becoming highly persistent in nature. For instance, the half life of reactive blue 19 is about 46 years at pH 7 at 25ºC (Hao et al. 2000)." href="javascript:void(0)"><b>accumulation</b></a> of azo dyes in water bodies where they are then ingested by aquatic organisms. Additionally, irrigation of agricultural lands with dye polluted water severely affects soil fertility and <a data-tip="true" class="top large" data-tip-content="It affects different plant growth parameters namely | ||
Revision as of 12:38, 15 October 2014
Since their accidental discovery by Sir William Henry Perkin in 1853, azo dyes have become one of the most popular forms of synthetic colourant. These dyes are currently used in the industrial manufacture of a variety of products, ranging from clothing and upholstery to cosmetics and tattoo ink, as well as many others.
Although azo-dyes are widely regarded as a safe and stable form of synthetic colourant, some of them can take on dangerous properties after they have been broken down by enzymes in the guts of organisms.
In the textile industry alone, the global annual production of dyes amounts to a million metric tons. In many countries, the leftover dye effluent produced by industrial manufacturers is often not properly disposed of, or removed, during water treatment.
This results in the accumulation of azo dyes in water bodies where they are then ingested by aquatic organisms. Additionally, irrigation of agricultural lands with dye polluted water severely affects soil fertility and plant growth.
The products of this enzymatic breakdown have been found to be both mutagenic and carcinogenic, and have been linked to increased occurrences of several different forms of cancer if they enter the food chain. Despite this toxicity and it's potential effect on human health, little to no effort has been made to dispose of these leftover azo dyes more responsibly.
As a result, development of remediation technologies for treatment of dye containing waste waters has been a matter of major concern for environmentalists.
For our iGEM project we developed a process to controllably degrade and detoxify the excess azo dye effluent at the source - the textile factories - before they even reach the water systems. We achieved this goal by introducing the genes for three enzymes related to the degradation of these dyes: azoreductase, laccase, and lignin peroxidase into a host E.coli cell to create an enhanced azo dye decolourising organism.
Click on our lab team logo to learn more about our BioBricks!
We also designed an integrated end-of-pipe method for detoxifying dye factory wastewater effluent streams by incorporating our engineered E. coli strain in a two-stage process to ensure optimal conditions for the degradation of azo dyes within a batch bioreactor system. The potential for scalability of this method would present various economic and environmental advantages for industries that generate large amounts of dyestuff. The system we have developed could also be enhanced to become a modular bioprocess method for wastewater treatment of other toxic, normally recalcitrant chemicals.
Click on our bioprocessing team logo to learn more about our bioprocess!
This year, UCL has a highly interdisciplinary team of undergraduates and postgraduates, all with a burning passion and love for our project, our little synbio community, and what it could become in the future. We are all genuinely delighted to be trying to bring synthetic biology to the world around us.
Click on our human practices team logo to learn more about us!
