France-based DEINOVE and US-based MBI have formed a technological partnership to demonstrate the effectiveness of the DEINOVE’s DEINOL technology for producing biofuels based on lignocellulosic biomass (2G biofuels) using MBI’s AFEX (ammonia fiber expansion) pretreatment system.
DEINOL uses Deinococcus bacteria to break down the complex sugars contained in pre-treated lignocellulosic biomass and then to convert them into ethanol in a single operation, replacing the microorganisms that are traditionally used and a large part of the enzyme treatment that precedes fermentation. (Earlier post.) MBI, in close collaboration with Michigan State University (MSU), has developed and is scaling up its AFEX pretreatment technology. (Earlier post.)
After testing its process on simple sugars such as glucose and xylose, DEINOVE contacted MBI to test the DEINOL technology on AFEX-pretreated corn stover.
Preliminary tests showed the assimilation of more than 95% of all the sugars available in the biomass and the production of ethanol, a process called “Simultaneous Saccharification and Fermentation.” DEINOVE said the results demonstrate the effectiveness of AFEX technology in releasing the cellulose and hemicellulose found in the biomass, and the effectiveness of Deinococcus in assimilating and metabolizing the material obtained.
The preliminary results obtained by combining AFEX and Deinococcus not only confirmed the performance of each one of our technologies, but also demonstrated a compelling synergy between both. The results obtained so far confirm the extraordinary fermenting capabilities of Deinococcus bacteria, as well as their significant potential for product cost reduction. This combination is highly promising, and it could provide an answer for an industry that is seeking a technologically and economically competitive solution to the challenge of producing sustainable, low-cost biofuels.—Allen Julian, MBI’s Chief Business Officer
AFEX. AFEX is an ammonia-based pretreatment technology for cellulosic biomass. This technology was initially developed by Professor Bruce Dale of Michigan State University after more than 20 years of research on biomass conversion and industrialization. In 2011, MBI received a $4.3-million grant from the US Department of Energy to take AFEX technology from the laboratory prototype stage (10 liters) to the pilot scale (1,000 liters and more).
Pretreatment processes all seek to dissociate the various components of biomass (cellulose, hemicellulose, and lignin) to hydrolyze complex sugars into simple sugars that are then fermented into molecules of industrial interest. In practical terms, pretreatment enables enzymes or microorganisms to digest biomass. Various thermal, chemical, or mechanical, pretreatment processes exist.
The AFEX process (a basic alkaline process) is one of the more effective pretreatment methods both for reducing the production of inhibitors during the process and for increasing the accessibility of cellulose and hemicellulose.
DEINOL. DEINOL is a production system aimed at converting pretreated industrial biomass into ethanol. The DEINOL process provides competitive advantages, observed by MBI in Deinove’s laboratory, that will enable industries to produce 2G biofuels under better financial conditions than currently available technologies:
Deinococcus bacteria are the only microorganisms that are able to co-assimilate all C6 and C5 sugars found in industrial biomass (glucose, xylose, also arabinose, etc.) and can even do so without diauxie, significantly improving yield and reducing fermentation time. They are also able to assimilate oligomers, i.e. partially hydrolyzed sugar chains, a significant benefit in terms of time and cost.
The yeasts currently used by industry first assimilate the C6 sugars (glucose) before they more or less effectively assimilate the C5 sugars (xylose, arabinose, etc.): fermentation time is significantly longer than with Deinococcus, with lower yields.
Deinococcus bacteria are resistant to a large number of inhibitors produced during pretreatment, thus optimizing production conditions.
Due to the thermophilic qualities of Deinococcus bacteria and their ability to hydrolyze (partially) and ferment biomass into ethanol at the same time, the DEINOL process can reduce equipment investments and production costs, while at the same time reducing the risk of contamination.