23.feb.07
CropBiotech Update
http://www.isaaa.org/kc
There has been a growing concern on the effect of non-degradable plastic wastes on the environment. Pornpa Suriyamongkol and colleagues in Canada, say that one solution is to use naturally produced plastic compounds, called polyhydroxyalkanoates (PHAs). PHAs have many potential applications in the food industry (in bottles and other food material packaging), and in medicine (in implants, gauzes, and suture filaments).
PHAs has been found to bio-degrade in 3-9 months, and mass production can be done using plants or microorganisms. Suriyamongkol and colleagues believe that the use of plants is considerably less expensive than in bacteria because the former does not need the costly requirements used in growing the microorganisms, such as sterile environment, fermentation equipments, and electricity.
The efficiency of producing PHA in transgenic plants has already been examined by using the model plant Arabidopsis and several crop species. The main challenge is how to produce commercially viable levels (greater than 15% dry weight) of PHA in the transgenics. If the desired level is attained, it is hoped that the cost of producing bio-plastics in plants could be lower or equivalent to the cost of producing petroleum-based polymers, which is about $1/kg.
Subscribers to the journal Biotechnology Advances may read the complete review at
http://dx.doi.org/10.1016/j.biotechadv.2006.11.007