"Pine Aroma" Against Beetle Invasion

GRAZ, AUSTRIA, June 27, 2013 (Press-News.org) Pine trees and red ants have something in common: Both use alkaloids to banish enemies. These organic ingredients are more and more in demand because of their environmental friendliness and safety. The problem is that they are only present in minimal amounts in natural form. Chemical synthesis in turn is complicated and expensive. Researchers at the Austrian Centre of Industrial Biotechnology (acib) and at the University of Graz led by Prof. Wolfgang Kroutil have now developed a new key technology to produce a promising alkaloid variety much easier than ever using biocatalysis.

So remarkable the about half an inch wide pine weevil is, so harmful it can be. The insects, which play dead at the slightest vibration, live on young spruce or pine trees, where they place their eggs into the stocks. Occurring in large numbers, the critters can cause great harm, because the infected trees are consistently condemned to death. "In the northern hemisphere, this could be a real problem", says Prof. Wolfgang Kroutil of the University of Graz. Natural alkaloids are perfect remedies, which expel the beetles in a biological manner. The function of the alkaloid is similar to territorial marking of predators: If a newbie finds a marking scent, he knows that there is already someone else in place and he stays clear of the area. One of these alkaloids is "Dihydropinidine" which belongs to the class of 2,6-dialkylpiperidines. The substance has a major drawback: In its natural form it is present only in minute quantities in some pine varieties. Until now the production of this substance in larger quantities has nearly been impossible, because up to 14 very sophisticated, chemical synthetic steps were necessary.

An acib-research group led by Prof. Kroutil found a new approach to this class of substances. "The problem with many syntheses is that you have to protect certain parts of the parent molecule to get the desired reaction only at a certain position", explains the researcher. Without protection, the result is an useless substance. For chemists, this means to attach a protective group, perform the reaction, remove the protective group, add a new protective group at a different position, carry out the next reaction, cleave the protective group, and so on - until the desired substance is eventually synthesized in minimal quantities.

The acib-researchers have found an enzyme, which reduces the 14 to only 3 reaction steps. The first and last steps of the synthesis are "chemical", the central one will be accomplished by a highly specific "omega transaminase". This enzyme yields the product avoiding the undesired byproducts occurring in the chemical approach. This saves time and energy and reduces the use of environmentally harmful organic solvents. Thus the new method is not only a step forward in the battle against the beetle but opens up new opportunities in the production of biologically highly active alkaloids.

Using the new synthesis technique, the chemical industry can synthesize environmentally friendly products against pests based on dialkylpiperidin including antifeedants as that against the pine weevil but also agents against bacteria (bactericids) or fungi (fungicides) that can be produced on a commercial scale now. Just recently, the method of producing "Isosolenopsin" has been adapted. The substance is an alkaloid oozed by red ants for defense. It is interesting for industrial application because it has strong antibacterial properties. In addition, it acts anti-hemolytic (prevents the destruction of red blood cells) or anti-necrotic (helps against the death of tissue).

The importance of the new concept developed within the internal acib-partnership is proven by its publication in the well known scientific journal "Angewandte Chemie". The method was engineered in a research project with Sandoz.

About ACIB
The Austrian Centre of Industrial Biotechnology (acib) is the international Centre for Industrial Biotechnology with locations in Graz, Innsbruck, Tulln and Vienna. As a research center of excellence, acib is an international partnership of currently 10+ universities and 30+ project partners, including large companies such as BASF, DSM, Sandoz, Boehringer Ingelheim, Jungbunzlauer, F. Hoffmann-La Roche, Novartis, VTU Technology or Sigma Aldrich. Owners are the Universities of Innsbruck and Graz, Graz University of Technology, the University of Natural Resources, Vienna and Joanneum Research.

At acib, 190 employees work in more than 40 research projects. Public funding (58% of the budget) comes from the Research Promotion Agency of the Republic of Austria (FFG), the country Tyrol, the Styrian Business Promotion Agency (SFG) and the Technology Agency of the City of Vienna (ZIT). The EU funds additional projects such as CHEM21.

The competence center acib - Austrian Centre of Industrial Biotechnology - is sponsored within COMET (Austrian Competence Centres for Excellent Technologies) by the BMVIT, BMWFJ and the provinces of Styria, Tyrol and Vienna. The COMET program is handled by the FFG.

Website: http://www.acib.at