“It is important to obtain an extremely pure product from fermentation”, explains Marc Ongena. “This is due to the fact that, where conventional phytopharmaceutical products are concerned, biopesticides must be seen to be of a clear and transparent composition, in order to be officially approved”. At the current time, this bioreactor, although it is very efficient, is small in volume and can only supply a few milligrams of molecules a day.  In time, thanks to the continuous production mode, it is expected to grow to the point where it is on a semi-industrial scale and can produce several grams per day. This is the main mission of the “Lipofabrik” spin-off, which was set up last spring by the project partner in Lille.

The cosmetic and food industries show interest

The interest of these discoveries goes beyond the strict area of phytopharmaceutical application. Interested by the surfactant/surface-active and antimicrobial properties of these molecules, several firms active in the food and cosmetics industries have already contacted the participants of “Phytobio”. This is because lipopeptides can, for example, help in the fabrication of the ideal texture for creams and ointments (while also having antiseptic properties).  Can it be said at this stage that lipopeptides are necessarily less toxic (for humans and the environment) than the synthetic molecules used in traditional pesticides? “We don’t know whether they are toxic for humans”, acknowledges Marc Ongena. “But we have reason to be very optimistic. Because these molecules are natural and offer a fatty acid peptide structure, we already know that they are easily biodegradable, developing a very low residual persistence in fruit, vegetables, cereal crops etc.”

As to whether they are toxic for the environment, the researcher from Liege recognizes that the team from interreg had some concerns in relation to this matter because these surfactant amphiphilic molecules can show similarities to detergents. However, the first tests with regard to ecotoxicity have been reassuring. All the lipopeptides tested, the Surfactins, Iturins and Fengycins, are several thousand times less toxic that many synthetic molecules. “We are beginning to understand that these molecules develop a very specific antibiotic activity. Iturin, for example, is a powerful antifungal agent which is very efficient for causing the cellular membrane of some fungi to collapse but it has little or no effect on bacteria or other varieties of fungi. These targeted molecules can therefore not be described as a “shot in the dark”. For this reason they are extremely promising for targeted applications”.

A noticeable reduction in chemistry

In addition, this work which will be completed in March 2014, opens up the possibility that these biopesticides containing several lipopeptides can be perfected, each one having its specific mode of action. Therefore, some of them can directly fight against the pathogens and others can strengthen the immunity of the plant. This is a sort of multiple action which would reduce to zero the mechanisms of adaptation and resistance of pathogens that are well-known in in vegetables treated with traditional pesticides. “Due to the long periods necessary before any official approval is granted, it will take several additional years before these new molecules are routinely used by farmers.  They will probably use them as a complement to or alternately with chemical pesticides. But even if chemical pesticides were reduced by 40%, or even 60% or more, this would already represent immense progress”.  It must be modestly added that, should these lipopeptides reach the marketing stage as bacterial molecules, it would be a first in global terms…