Scientists decode entire genome of biopolymer producing bacterium
The bioeconomy has received another boost: scientists from the University of Göttingen, the University of Münster and of Berlin's Humboldt University have succeeded in sequencing the entire genome of Ralstonia eutropha. This harmless bacterium which thrives in the soil and in cold waters, is used to produce biopolymers, in particular biopolyesters, from renewable biomass.
Bioplastics can be produced via two main routes: the first consists of a process whereby lactic acid is fermented from sugar. After the lactic acid is produced, it is converted to polylactic acid using traditional polymerization processes; the second consists of direct bacterial polyester fermentation. Contrary to the first technique, bacteria use the sugar of biomass to fuel their cellular processes, while they directly produce a polymer as a byproduct. These polymers are then separated from the bacterial cells.
The microorganism used in direct bacterial polyester fermentation is Ralstonia eutropha. It fuels itself with the hydrogen contained in biomass (which it derives from fermenting sugars and starch) and oxygen, and combines the two to form polyesters. The bacterium's genetic patrimonium was found to consist of two chromosomes containing 6116 genes. The precise function of 4000 of these has been identified, making it possible to design new bioproducts:
ethanol :: bioenergy :: biofuels :: energy :: sustainability :: genome :: bacterium :: biopolymers :: biomass :: bioeconomy ::
Anne Pohlmann of the Institut für Mikrobiologie, Berliner Humboldt-Universität: "From now on we can look at and into the organism, see which products we can derive from it, and decide which one to produce at any given time."
Because Ralstonia eutropha has such a robust and flexible enzymatic machinery, able to fuel itself on many different carbon and energy sources, it can be used to produce a very broad range of biomolecules, based on the specific sugars and starches it is allowed to feed on:
Researchers from the Humboldt University have found a range of applications that go beyond producing biodegradable plastics: the bacterium can be used to produce alcohols and biohydrogen.
The scientists are now focusing on 53 very interesting genes that could be used to make special polyesters and entirely novel kinds of biomolecules.
More information:
L'Usine Nouvelle: La génétique bactérienne au service des bioplastiques - Oct. 20, 2006
Handelsblatt: Plastik der Zukunft kommt vom Acker - Oct. 6, 2006
Biobasics: Biopolymers and Bioplastics - introduction to the topic.
Research files from the University of Humboldt: Ralstonia eutropha.
Article continues
Bioplastics can be produced via two main routes: the first consists of a process whereby lactic acid is fermented from sugar. After the lactic acid is produced, it is converted to polylactic acid using traditional polymerization processes; the second consists of direct bacterial polyester fermentation. Contrary to the first technique, bacteria use the sugar of biomass to fuel their cellular processes, while they directly produce a polymer as a byproduct. These polymers are then separated from the bacterial cells.
The microorganism used in direct bacterial polyester fermentation is Ralstonia eutropha. It fuels itself with the hydrogen contained in biomass (which it derives from fermenting sugars and starch) and oxygen, and combines the two to form polyesters. The bacterium's genetic patrimonium was found to consist of two chromosomes containing 6116 genes. The precise function of 4000 of these has been identified, making it possible to design new bioproducts:
ethanol :: bioenergy :: biofuels :: energy :: sustainability :: genome :: bacterium :: biopolymers :: biomass :: bioeconomy ::
Anne Pohlmann of the Institut für Mikrobiologie, Berliner Humboldt-Universität: "From now on we can look at and into the organism, see which products we can derive from it, and decide which one to produce at any given time."
Because Ralstonia eutropha has such a robust and flexible enzymatic machinery, able to fuel itself on many different carbon and energy sources, it can be used to produce a very broad range of biomolecules, based on the specific sugars and starches it is allowed to feed on:
Researchers from the Humboldt University have found a range of applications that go beyond producing biodegradable plastics: the bacterium can be used to produce alcohols and biohydrogen.
The scientists are now focusing on 53 very interesting genes that could be used to make special polyesters and entirely novel kinds of biomolecules.
More information:
L'Usine Nouvelle: La génétique bactérienne au service des bioplastiques - Oct. 20, 2006
Handelsblatt: Plastik der Zukunft kommt vom Acker - Oct. 6, 2006
Biobasics: Biopolymers and Bioplastics - introduction to the topic.
Research files from the University of Humboldt: Ralstonia eutropha.
Article continues
Sunday, October 22, 2006
Banana biogas to power heavy-duty farming equipment and vehicles
The plant will be constructed and operated in the next 12 months on the plantation of Bush Holdings at Tully. About 10 per cent of bananas are currently discarded in the Queensland banana industry every year due to imperfections which make them unsuitable for sale. “Bush Holdings, one of the industry’s larger growers, has agreed to partner with us to provide the constant supply to the plant required for the pilot project,” said Growcom CEO Jan Davis.
There are several advantages when using bananas for biogas:
- they produce a very clean form of biogas, consisting of just methane and CO2, compared to biogas derived from other waste streams such as human sewage, piggery or feedlot waste which contains many different trace elements
- the methane production process releases less noxious odours compared to that based on other feedstocks
- the yields are very high due to the easy fermentability of bananas
In Europe, there is a lot of activity around biogas, with researchers developing dedicated biogas crops (super maize and hybrid grasses). Several regions, especially in Germany, are already producing a large amount of it from such dedicated biomass crops, which are easier to manage as a feedstock than municipal or industrial waste-streams. A hectare of dedicated biogas maize, for example, yields the energy equivalent of around 4000 liters of diesel fuel. The potential for biogas in Europe is very large (earlier post), and as a transport fuel it has many advantages over other renewable fuels (most importantly: of over 70 different fuels and fuel-paths, biogas is the most environmentally friendly - earlier post).Now it would be interesting to study how much biogas can be derived from tropical crops, like bananas and plantains:
biomass :: bioenergy :: biofuels :: energy :: sustainability :: Africa :: biogas :: banana ::
In the developing world, biogas could be on its way to becoming a widely used fuel, both in transport and as a decentralised energy source for stationary applications (see here, here and here). (In a futuristic scenario, remote energy producing communities may even produce biogas that is airlifted to large cities - earlier post.) So instead of merely using waste bananas from existing industries, they should be studied as potential dedicated energy crops for large-scale methane production; instead of exporting uniform 'Euro-bananas' (a cumbersome process involving lots of middlemen, the profits of which never arrive at the small producers) they should be looked at as valuable sources of locally available energy. Bananas and plantains have high biomass yields: for bananas they can go up to 50 tonnes per hectare, for plantains up to 40 tonnes. Added are several tonnes of leaves and stems.
But for the time being, we should await the results from an initiative like that in Queensland. The project has clear targets and already some research that proves its viability: “We anticipate that the pilot plant will begin producing gas in about five months’ time and we hope it will prove that the gas can be produced in commercial quantities and compressed for use in combustion engines to power tractors and machinery. We expect the project will confirm the research findings made by the Division of Environmental Engineering at the University of Queensland last year. Researchers showed that natural gas could be produced from bananas using a ‘continuous digestion’ process involving natural microbial organisms. “We plan to transform their work from the laboratory benchtop into a full scale pilot plant on farm.”
“We hope that scaled up production could ultimately see a cheaper alternative fuel to petrol produced at the larger packing sheds on farm, saving growers a significant amount on their annual fuel bill. “The technology also has the potential to be transferred to other fruit and vegetable commodities such as apples in other regions.”
More information:
FreshPlaza: Banana biofuels project aims to reduce growers’ fuel bills - Oct. 20, 2006
Article continues
posted by Biopact team at 8:40 PM 0 comments links to this post