More meticulous separation of cells
“Learning how to separate cells step by step so that they fall apart slowly in undamaged, useable components.” This is how Michel Eppink describes the challenge he and his students are facing. The enthusiastic Eppink was recently appointed as special professor in ‘Biorefinery: recovery of valuable biomolecules’ at Wageningen UR.
In addition to oils and fats, professor Eppink is also looking to extract sugars, proteins, fatty acids, pigments and vitamins from important biomass resources such as algae. In fact, he hopes to extract all the renewable materials that can be used in biobased applications in the field of food, health care and fuel. But to do so requires major steps in the technologies for cell fragmentation and the purification of functional biomolecules.
“Many valuable components are lost in the current separation and refinery techniques, which are mainly chemical or mechanical,” says Eppink. “This makes them unprofitable. If the only result is biofuel, biorefinery is economically unfeasible. We need to develop new techniques which will allow us to separate cells in a controlled way and there are various interesting research options. Pressing and milling are ones we know but there are many other separation techniques, such as steaming under high pressure, ultrasonic pulses, electricity and light. Not enough research has been performed into these alternative separation techniques.”
The model system Eppink uses for his research works with the properties of algae. “But we are aiming for techniques that also apply to other single-cell, cultivatable organisms such as yeast. One of the most difficult steps in the refinery process is the separation of hydrophilic components, such as carbohydrates and protein, and hydrophobic components, such as fats. The trick is to break open cells in such a way that the components remain undamaged. In current techniques, the focus is on just fats or just proteins. Everything else is lost.”
Over the past 17 years Eppink has managed departments at a number of separation technology companies. His return to Wageningen UR, where he obtained his doctoral degree in 1999, is largely based on idealistic motives.
“The industry is essential for a genuine transition to a biobased economy and companies must invest in and implement innovations. The drive and knowledge should be provided by the generation that is in university now. I believe in aiming for the long term and want to contribute my knowledge and experience to their education. It could easily be another ten to fifteen years before we are able to extract components for food, biobased chemicals, medication and energy from green raw materials. I am pleased that an increasing number of students are interested in learning about new separation technologies.”