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 Cancer diagnosis: no more needles?
25.05.2018 | Christian-Albrechts-Universität zu Kiel

nachricht Less is more? Gene switch for healthy aging found
25.05.2018 | Leibniz-Institut für Alternsforschung - Fritz-Lipmann-Institut e.V. (FLI)

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Powerful IT security for the car of the future – research alliance develops new approaches

The more electronics steer, accelerate and brake cars, the more important it is to protect them against cyber-attacks. That is why 15 partners from industry and academia will work together over the next three years on new approaches to IT security in self-driving cars. The joint project goes by the name Security For Connected, Autonomous Cars (SecForCARs) and has funding of €7.2 million from the German Federal Ministry of Education and Research. Infineon is leading the project.

Vehicles already offer diverse communication interfaces and more and more automated functions, such as distance and lane-keeping assist systems. At the same...

Im Focus: Molecular switch will facilitate the development of pioneering electro-optical devices

A research team led by physicists at the Technical University of Munich (TUM) has developed molecular nanoswitches that can be toggled between two structurally different states using an applied voltage. They can serve as the basis for a pioneering class of devices that could replace silicon-based components with organic molecules.

The development of new electronic technologies drives the incessant reduction of functional component sizes. In the context of an international collaborative...

Im Focus: LZH showcases laser material processing of tomorrow at the LASYS 2018

At the LASYS 2018, from June 5th to 7th, the Laser Zentrum Hannover e.V. (LZH) will be showcasing processes for the laser material processing of tomorrow in hall 4 at stand 4E75. With blown bomb shells the LZH will present first results of a research project on civil security.

At this year's LASYS, the LZH will exhibit light-based processes such as cutting, welding, ablation and structuring as well as additive manufacturing for...

Im Focus: Self-illuminating pixels for a new display generation

There are videos on the internet that can make one marvel at technology. For example, a smartphone is casually bent around the arm or a thin-film display is rolled in all directions and with almost every diameter. From the user's point of view, this looks fantastic. From a professional point of view, however, the question arises: Is that already possible?

At Display Week 2018, scientists from the Fraunhofer Institute for Applied Polymer Research IAP will be demonstrating today’s technological possibilities and...

Im Focus: Explanation for puzzling quantum oscillations has been found

So-called quantum many-body scars allow quantum systems to stay out of equilibrium much longer, explaining experiment | Study published in Nature Physics

Recently, researchers from Harvard and MIT succeeded in trapping a record 53 atoms and individually controlling their quantum state, realizing what is called a...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

12th COMPAMED Spring Convention: Innovative manufacturing processes of modern implants

28.05.2018 | Event News

In focus: Climate adapted plants

25.05.2018 | Event News

Save the date: Forum European Neuroscience – 07-11 July 2018 in Berlin, Germany

02.05.2018 | Event News

 
Latest News

Cognitive Power Electronics 4.0 is gaining momentum

28.05.2018 | Trade Fair News

Organic light-emitting diodes become brighter and more durable

28.05.2018 | Physics and Astronomy

12th COMPAMED Spring Convention: Innovative manufacturing processes of modern implants

28.05.2018 | Event News

VideoLinks
Science & Research
Overview of more VideoLinks >>>