From “ordinary” wood to an incredibly intense raspberry aroma?

SME of the Month, Phytowelt GreenTechnologies, shows a great example on how biotech can influence every part of circular economy

What do poplar wood, genome analysis and intestinal bacteria have to do with a natural raspberry aroma?

The Biotech SME of the Month, Phytowelt GreenTechnologies, combined these, at the first glance seemingly incoherent points, in a circular approach to produce a unique aroma to meet market demands. In this short chapter of the long story we want to focus on the “hard stuff”, poplar wood.

One pillar of Phytowelt’s business concept is the development of bio-fermentation processes for fine chemicals like their natural raspberry aroma R-alpha-Ionon. Shortly summarized it works like this: Genetically modified bacteria feed in a controlled environment on a carbon source, mostly glucose, to produce a desired valuable substance. Glucose and other sugars are already a renewable resource, but they are also part of human nutrition. To produce another feedstock for the bacteria and to circumvent the conflict of food vs. biomass production, Phytowelt decided to optimize a classical biomass plant, poplar, which can be cultivated on marginal lands that are unsuitable for food production.

One of Phytowelt´s poplar/aspen variety testing fields over the course of the year, Cologne, Germany

Here, Phytowelt’s other main pillar steps into action - the green biotech and tissue culture department. Based on two decades of know-how, the scientist of Phytowelt decided to breed new hybrids of the well-known biomass plants poplar and aspen. These two closely related tree species are often cultivated in short rotation coppices to produce wood chips for various uses, i.e. concentrated extracts like wood hydrolysates. These can be used as carbon source for bio-fermentation. Breeding new tree varieties which are adapted to specific climates and optimized for biomass production takes up to 15 years due to long reproduction cycles and proportionally slow growth. That’s why the diversity of varieties is very low and none of the varieties did fulfil all of Phytowelt’s demands. So within a funded project, new hybrids of poplar and aspen have been bred via a special technique called protoplast fusion. A protoplast is a cell, cleared of its cell wall and hold together only by its plasma membrane. Such cells, including all cell compartments, can be fused to form a new cell with new properties.

Now, whole plants with new traits can be regenerated from these fused protoplasts. Especially the combination of different plastids (e.g. chloroplasts and mitochondria) generates new genetic variety one could not generate by classical cross breeding. Never the less, this technique is not considered as genetic modification as long as one hybridizes species that hybridize in nature as well. This is the case for poplar and aspen. Out of thousands of individual protoplast fusions and regenerated plants, the most superior individuals have been selected, from which already three have been registered as new variety. Within 7 years Phytowelt bred and registered new hybrid varieties, which show accelerated biomass production and faster growth compared to their parental lines and elite varieties. These will soon be used to produce a renewable feedstock for the production of the natural raspberry aroma and thereby close the supply chain for sustainable production of a unique product.

Phytowelt impressively shows how scientific creativity fosters innovation and gives rise to alternative methods to those politically restricted. Biotech can positively influence all parts of a circular economy, from “ordinary” wood to bacteria and the sweet smell of ripe raspberries.