With the race for renewable energy sources in full swing, plants offer one of the most appealing prospects for changing petroleum. Lignocellulose in particular– biomass from non-edible plants like turf, leaves, and wood that don’t take on food crops– is abundant and eco-friendly and uses an excellent alternative source to petroleum for an entire series of chemicals.
In order to extract beneficial chemicals from it, lignocellulose is very first pretreated to “break it up” and make it easier to more process. Then it’s exposed to enzymes that solubilize cellulose, which is a chain of linked sugars (glucose). This step can be done by adding to the pre-treated lignocellulose a microorganism that naturally produces the essential, cellulose-cleaving enzymes, e.g. a fungus.
The enzymes “fracture” the cellulose and turn it into its private sugars, which can be more processed to produce an essential chemical: lactic acid. This second step is also achieved with a microbe, a bacterium that “eats” the sugars and produces lactic acid when there’s no oxygen around.
In the last action of this microbial assembly line, the lactic acid can then be processed to make a whole host of beneficial chemicals.
A team of scientists from the Bern University of Applied Sciences (BFH), the University of Cambridge, and EPFL have made this assembly chain possible in a single setup and showed this conversion can be made more versatile and modular. By easily swapping out the bacteria in the last, lactic-acid processing, action, they can produce an entire series of helpful chemicals.
The breakthrough research study is released in Science, and was performed by Robert Shahab, an EPFL PhD trainee in Professor Jeremy Luterbacher’s lab, while operating at the lab of Professor Michael Studer at the BFH, who led the study.
The researchers provide what they describe as a “lactate platform,” which is essentially a spatially segregated bioreactor that permits numerous different microbes to co-exist, each performing one of the three steps of lignocellulose processing.
The platform consists of a tubular membrane that lets a specified amount of oxygen to go through it.
However the innovation that Shahab made remained in the last action. By using different lactic acid-fermenting microbes, he was able to produce various helpful chemicals. One example was butyric acid, which can be used in bioplastics, while Luterbacher’s lab recently showed that it can even be become a jet fuel.
The work demonstrates the advantages of combined microbial cultures in lignocellulose biomass processing: modularity and the ability to convert intricate substrates to valuable platform chemicals.
” The outcomes attained with the lactate platform perfectly show the benefits of artificial microbial consortia to form new items from lignocellulose,” says Michael Studer. “The production of specific niches in otherwise uniform bioreactors is an important tool to co-cultivate various bacteria.”
” Fermenting lignocellulose to a great deal of different products was a substantial quantity of work however it was important to demonstrate how flexible the lactate platform is,” says Robert Shahab. “To see the development of lactate and the conversion into target items was a great experience as it showed that the principle of the lactate platform operated in practice.”
Jeremy Luterbacher includes: “The ultimate goal is to reconstruct a green manufacturing sector to change one that produces many items from petroleum. An approach that introduces flexibility and modularity is a crucial action in that instructions.”