Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Enzymes find pastures greener

17.04.2002


Chemists put biological catalysts to work in clean industrial solvents.



In a move towards cleaner chemical processing, researchers in Spain and France have worked out how to use enzymes as catalysts using two ’green’ solvents: one to dissolve the enzyme, the other to dissolve the materials it transforms.

In some industrial processes chemists have replaced polluting organic solvents, such as chlorine and benzene, with supercritical carbon dioxide. This is the liquid-like fluid that is made by putting carbon dioxide under moderately high pressure and at temperatures equivalent to a hot bath. Supercritical carbon dioxide dissolves many organic compounds used for chemical synthesis. It decaffeinates coffee, for example.


Another, more recent, green option is the use of ionic liquids - these are salts that are molten at room temperature. They too dissolve many organic compounds, and don’t give off nasty fumes.

Jose Iborra of the University of Murcia in Spain and co-workers have used a combination of supercritical carbon dioxide and ionic liquids to help an enzyme transform some organic molecules1. This is an ideal form of green chemistry, as it uses natural catalysts in clean solvents.

Enzymes are designed to work in water inside cells. But water won’t dissolve many of the organic reagents used in industrial and pharmaceutical chemistry. So many industrial processes that use enzymes as catalysts need organic solvents.

Unfortunately, enzymes typically don’t work well in carbon dioxide. "It reacts with the enzyme," explains chemist Eric Beckman of the University of Pittsburgh. This and other complications stop the enzyme working as a catalyst. Some enzymes, though, work well in ionic liquids. So Iborra’s group devised a two-phase reactor in which the organic starting materials are dissolved in supercritical carbon dioxide and passed through a chamber containing a yeast enzyme dissolved in an ionic liquid.

The enzyme converts the reagents to the desired products, presumably by reactions occurring at the boundary between the two solvents. Product molecules dissolve in the carbon dioxide and are carried out of the reaction chamber. The enzyme, which stays in the ionic solvent, is protected from the worst of the deactivating influence of carbon dioxide.

It’s not a perfect solution - some carbon dioxide can dissolve in the ionic liquid and so can still get at the enzyme. But it’s a lot better than trying to carry out the reaction entirely in carbon dioxide, which deactivates the enzyme quickly.

"It’s an intriguing idea," says Beckman, as using enzymes in supercritical solvents has previously been fraught with difficulties.

References
  1. Lozano, P. , de Diego, T., Carrie, D., Vaultier, M. & Iborra, J. L. Continuous green biocatalytic processes using ionic liquids and supercritical carbon dioxide. Chemical Communications, 2002, 692 - 693, (2002).


PHILIP BALL | © Nature News Service

More articles from Life Sciences:

nachricht Nanotubes built from protein crystals: Breakthrough in biomolecular engineering
15.11.2018 | Tokyo Institute of Technology

nachricht Insect Antibiotic Provides New Way to Eliminate Bacteria
15.11.2018 | Universität Zürich

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

When electric fields make spins swirl

15.11.2018 | Physics and Astronomy

Discovery of a cool super-Earth

15.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>