Many visits and email come looking for bio butanol information and in fact those efforts are justified. Butanol could be a one for one substitute for gasoline and could even be an extender or additive for diesel fuel. It’s a better panacea, if you’ll pardon term than ethanol, as it’s just a better fuel for internal combustion engines.

Late last week saw Hans Blaschek, microbiologist in the College of Agricultural, Consumer and Environmental Sciences at Illinois announce the publishing of his paper in the December 2008 issue of Applied and Environmental Microbiology about a breakthrough with the development of a mutant strain of a soil bacterium called Clostridium Beijerinckii that produces higher concentrations of butanol when added to a vat of plant byproduct.

Hans P Blaschek

Hans P Blaschek

Blaschek explains, “One of the beauties of Clostridium, is that unlike yeast that can only use six carbon sugars, this organism can use five or six carbon sugars, so you’re not limited. You can use distiller’s grains, biomass, pretty much anything that can be deconstructed to sugars and can be fermented. Clostridium eats both and it does it naturally. You don’t have to engineer the organism like people have been doing for the last 20 years with yeast trying to get it to use five carbon sugars.”

The story is, “When we did the original study 10 years ago that resulted in the mutant strain, we didn’t do it in a nice, careful way using sophisticated molecular biology. We did it using brute force and it worked. However, the problem with that approach is that you don’t really know what genetic alterations caused the enhanced production.” Now there’s one of those serendipity things. Blaschek goes on, “In 2004 we put a request in to the Department of Energy to sequence the parent strain. After we had access to the sequencing information, we were able to do the first global evaluation of the two strains – the one that over-produces butanol together with the parent strain — to see what genetic alterations were responsible for this attribute.”

Then the new strain and the original were fermented separately, sampled; the RNA isolated to see how much RNA was present at moments over the course of fermentation. The underlying assumption was that if there was more RNA there’s more protein. They have been at it doing it for a series of over 500 genes. Blaschek found that the amount of RNA being produced for certain enzymes involved in butanol production was much greater in the mutant strain than in the wild type. There was also a difference in the ability of the mutant to make spores.

Blaschek says that the organism doesn’t make any butanol until late in the fermentation process. So the thinking is that if you can prevent the organism from going into the next physiological state, which is sporulation, when the bug sets out to send its reproductive spores out, that you can keep it more or less producing butanol.

Blaschek says, “The next step is to take that knowledge and produce a second generation strain by not using the brute force approach that I used earlier, but actually going in and very specifically making those genetic alterations in a targeted sort of way. You would take the wild strain and mutate the gene for the characteristic that you’re interested in. And now that we have the sequence, we actually know where those genes are.”

The mutant strain produces higher concentrations of butanol, and has become the basis for Tetravitae BioSciences, a local company that licensed the patented strain from the University of Illinois and is scaling up to use the over-productive strain on a large scale – the size of an ethanol plant.

Meanwhile, butanol is currently being made from crude oil for industrial uses and products like paint thinner, brake fluid and plastics. Currently butanol is much more costly than gasoline. With attributes like clean burning, high energy density, and good prospects for bio sources, bio butanol could well find a market to displace or substitute for gasoline. There remain several unanswered problems, like the low concentration of butanol poisoning microorganisms, separation issues and other process matters.

In any case, what the paper makes clear is that the possible range of biomass to butanol has grown and the organism can produce to higher concentrations – both worthwhile results. Butanol is in fairness dozens of centuries behind ethanol and methanol in its development. The small carbon molecules are easier to make and do offer more hydrogen available if the market goes to fuel cells.

But for internal combustion, chemistry and industry butanol is a top target, the current best use if it can be made to market scales in the tens of millions of gallons per year. It’s worthwhile news, one more step.


2 Comments so far

  1. Jessica Brock on January 13, 2009 1:42 PM

    Great article. Alternative energy sources are imperative to the sustainability of our economies future! Please come and visit Valcent to see what we’re doing in efforts to promote algae biofuel. Come and see our commercial sized unit producing algae and turning into a valuable alternative energy source!
    Jessica Brock

  2. Ritu Kesarwani on September 16, 2009 4:53 PM

    Algal-butanol has potential to contribute in America’s fuel requirements and carbon dioxide sequestration to fight green house effect and global warming, algae are fastest growing plants and in presence of sunlight and CO2 they can double their mass with in 12 hrs.
    for more on algae to butanol pocess please visit.

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