Plastic fantastic—the future of biodegradables

Oct 17, 2011

Poly-3-hydroxybutyrate (PHB) is a thermoplastic polyester which occurs naturally in bacteria as Ralstonia eutropha and Bacillus megaterium. Even though PHB is biodegradable and is not dependent on fossil resources, this bioplastic has been traditionally too expensive to produce to replace petroleum-based plastics. New research reported in BioMed Central's open access journal Microbial Cell Factories describes an alternative method of producing PHB in microalgae.

PHB is synthesised in from acetyl-CoA using the enzymes ß-ketothiolase, acetoacetyl-CoA reductase and PHB synthase. The genes coding for these proteins were inserted into a diatom (Phaeodactylum tricornutum) resulting in expression of the enzymes and synthesis of PHB in cytosolic granules. After only seven days, about 10% of the dried weight of the diatoms was PHB.

Dr. Franziska Hempel and Prof Uwe Maier from the LOEWE-Centre Synmikro in Marburg, and Prof Alexander Steinbüchel from Westfälische Wilhelms-Universität, explained, "Millions of tons of petroleum-based plastic are consumed every year worldwide causing immense amounts of waste that can take thousands of years to biodegrade – if at all. Bacterial fermentation is expensive and while people have introduced a similar system into plants, plants are relatively slow growing and biofuel agriculture uses up valuable land. P. tricornutum needs little more than light and water to grow and can produce similar amounts of PHB to the plant systems in weeks rather than months."

In the quest to find biodegradable and renewable sources of these photosynthetic bioreactors may well provide an answer.

Explore further: Life's extremists may be an untapped source of antibacterial drugs

More information: Microalgae as bioreactors for bioplastic production, Franziska Hempel, Andrew S. Bozarth, Nicole Lindenkamp, Andreas Klingl, Stefan Zauner, Uwe Linne, Alexander Steinbuchel and Uwe G. Maier, Microbial Cell Factories (in press)

add to favorites email to friend print save as pdf

Related Stories

Trained bacteria convert bio-wastes into plastic

Nov 19, 2010

Dutch researcher Jean-Paul Meijnen has 'trained' bacteria to convert all the main sugars in vegetable, fruit and garden waste efficiently into high-quality environmentally friendly products such as bioplastics.

'Green' plastics could help reduce carbon footprint

Feb 11, 2009

More than 20 million tons of plastic are placed in U.S. landfills each year. Results from a new University of Missouri study suggest that some of the largely petroleum-based plastic may soon be replaced by a nonpolluting, ...

The sweetness of biodegradable plastics

Dec 14, 2010

Environmentalists around the world agree ― plastic bags are choking our landfills and polluting our seas. Now a Tel Aviv University researcher is developing new laboratory methods using corn starch and sugar to help ...

Recommended for you

Cohesin molecule safeguards cell division

Nov 21, 2014

The cohesin molecule ensures the proper distribution of DNA during cell division. Scientists at the Research Institute of Molecular Pathology (IMP) in Vienna can now prove the concept of its carabiner-like ...

Nail stem cells prove more versatile than press ons

Nov 21, 2014

There are plenty of body parts that don't grow back when you lose them. Nails are an exception, and a new study published in the Proceedings of the National Academy of Sciences (PNAS) reveals some of the r ...

Scientists develop 3-D model of regulator protein bax

Nov 21, 2014

Scientists at Freie Universität Berlin, the University of Tubingen, and the Swiss Federal Institute of Technology in Zurich (ETH) provide a new 3D model of the protein Bax, a key regulator of cell death. When active, Bax ...

Researchers unwind the mysteries of the cellular clock

Nov 20, 2014

Human existence is basically circadian. Most of us wake in the morning, sleep in the evening, and eat in between. Body temperature, metabolism, and hormone levels all fluctuate throughout the day, and it ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.