You can have a transformative world or materials at affordable prices — but if you want both, you might well be seeing dicarboxylic acids somewhere in the mix.
That’s why JBEI’s latest and greatest is worth a closer look, and we take one today in The Digest.
When we look at the opportunities in biomass sugars and fuels, the biggest challenge from a cost point of view is that sugars are roughly 53% oxygen by weight, and there’s no oxygen in a hydrocarbon fuel. Which means that no matter what chemistry you perform on a 12 cent pound of sugar, you’re starting with less than 6 cents worth of hydrocarbon potential, and the climb to competitiveness with petroleum is all uphill.
In the case of ethanol and methanol — these are oxygenated fuels, and the yields are higher, but there’s still a lot of oxygen blown off in converting sugars to ethanol — and, since that comes off primarily in the form of CO2, there’s some carbon loss along the way and there’s the greenhouse problem of venting CO2.
So, one of the biggest friends of biobased fuels are oxygen-replete organic molecules.
It doesn’t take a college degree in chemistry to figure that, to use a purely mathematic example, from glucose you could derive ethane, succinic acid and some water if you had a process that could make the conversion. Not to mention that the world is short on water and is always on the hunt for ethane, and there’s a lot more value in that product set than from making ethanol and CO2 from the same raw material.
Succinic acid is one of a very valuable set of molecules in the known world, when it comes to biomass conversion, known as the carboxylic acids and the dicarboxylic acids. We call the latter “DCA” in the remainder of this note so you don’t have a why-do-molecules-have-unpronounceable-names-the-length-of-a-Bible panic attack.
Perhaps the best known of them is the simplest one. That’s acetic acid, or vinegar. We’ll spare you the rest of the chemistry lesson — the main thing you need to know is that there are an entire family of them, they are full of oxygen, and most of them have known applications and especially in the world of nylons, cosmetics, paints, and fuel additives.
Basically, the Rockettes at Radio City Music Hall would be lost without them.
High yields from biomass sugars are one reason why companies like BioAmber and Verdezyne have been chasing DCAs— the other is that applications like nylon offer growing markets and attractive per-ton prices. But we also like them for the possibilities in producing oxygen-rich molecules and hydrocarbons from the same raw material.
For all those reasons, it’s exciting news when processes related to DCAs come around.
And therefore it’s super to report that researchers at the Joint BioEnergy Institute have developed a new method to synthesize DCAs and something known as mono-methyl ester derivatives of carboxylic acids from glucose intermediates (renewable feedstocks). Those are unhelpfully acronym’d as DCAMMEs.
On the surface, not a game-changer. There are commonly used production methods such as oxidation of cyclohexanone, oleic acid or other unsaturated fatty acids — to achieve the same end. Almost.
But the JBEI technology enables production of DCAs and DCAMMEs with a variety of chain lengths from renewable sources. For those other guys, the chain length is dependent on the structure of the precursor prior to oxidation. So, a lot more flexibility in industrial applications.
Very cool. And, one of those reasons it’s handy to have a national lab or two lying around. They don’t figure this stuff out in Burundi, despite the biomass sugars in replete supply there.
How do they do it?
For one, they use genetically modified E. coli microbes as biocatalysts for the production of DCAs — allowing for a large-scale, pharmaceutical approach to the synthesis of these compounds.
Specific to this technology, a gene coding for an enzyme that catalyzes methyl transfer, such as BioC, is overexpressed. The cell is then modified to overexpress TesA, which releases bound DCAs once they have been created within the E. coli microbe. These fatty acid derivatives can then go on to be used in a wide variety of chemical processes and products.
To find out more.
If I were you, I’d start with Peter Medlock. He has the key to the licensing paperwork drawer, and speaks fluent Acronym as well as fine English. They’ll send you here http://ipo.lbl.gov/lbnl2014-158/ but try him here first 510-486-5803 or PYMatlock@lbl.gov.