Polyhydroxyalkanoates industrial applications

G. Q. Chen, Polyhydroxyalkanoates, in Biodegradable Polymers for Industrial Applications, CRC, Florida, USA, 2005. 

Hazer, B., and Steinbtichel, A. (2007) Increased diversification of polyhydroxyalkanoates by modification reactions for industrial and medical applications. Appl. Microbiol. Biotechnol., 74, 1-12. 

Abstract Studies have shown that the production of polyhydroxyalkanoate (PHA) from plant oils is more efficient than from sugars in terms of productivity. Among the various plant oils, pahn oil is the most efficiently produced oil in the world. The main application of pahn oil is as a source of dietary fat. The conversion of food grade substrates to non-food materials is of concern because of the increasing need to feed the rapidly growing human population. Therefore, the by-products of the plant oil industry may be a better feedstock for PHA production. Alternatively, non-food grade oils such as jatropha oil can be developed as a feedstock for PHA production. This chapter looks at the potential of jatropha oil as a possible feedstock for the biosynthesis of PHA. 

Abstract Polyhydroxyalkanoate (PHA) is an attractive material because it can be produced from renewable resources and because of its plastic-like properties. In addition, PHA can be degraded by the action of microbial enzymes. Although PHA resanbles some commodity plastics, the performance and cost of PHA are not yet good enough for widespread applications as plastic materials. Therefore, the PHA commercialization attempts by many industries for bulk applications have been challenging. However, PHA also possesses interesting properties that can be developed for non-plastic applications. This chapter describes some new niche applications for PHA in cosmetics and wastewater treatment. 

In the present chapter, rayon and other man-made cellulose fibers wUl be introduced in terms of properties and stracture. The compounding method to obtain the composites will be described briefly. PP-rayon composites will be considered in more detail as the practically most relevant class of this type of material at present arousing interest from the automotive industry. In another section rayon composites with poly(lactic acid) (PLA) and polyhydroxyalkanoates (PHA) will be studied as a promising bio-based and biodegradable alternative to conventional materials in durable applications, transport, and automotive industry. Finally, some concluding remarks will be given concerning future prospects of rayon reinforced thermoplastics and the problems to be tackled in future work. 

If it is possible to produce polyhydroxyalkanoates at a cost of 1-2 EUR per kg, a diverse range of potential applications become commercially very attractive. According to some industry specialists, this price range is already feasible with current, large-scale and fully integrated bioreactors and downstream processing technology [5]. 

Chen GQ.A polyhydroxyalkanoates based bio- and materials Industry. ChemSoc Rev 2009 38 2434-46. Chen GQ, Wu Q. Microbial production and applications of chiral hydrox dkanoates. Appl Microbiol Biotechnol 2005 67 592-9. 

Category 3 Polymers, which are produced by microoiganisms or genetically modified bacteria. Till date, this group of bio-based polymers consists mainly of the polyhydroxyalkanoates but developments with bacterial cellulose and other polysaccharides are also in progress. Figure 2 represents the various sources of currently used biopolymers sources which find profound application in food industry mainly in packaging. 

Bertrand J, Ramsay B, Ramsay J, Chavarie C (1990) Biosynthesis of poly-p-hydroxyalkanoates frmn ptaitoses by Pseudomonas pseudoflava. Appl Envirrai Microbiol 56(10) 3133-3138 Bramer CO, Vandamme P, da Silva LF, Gomez JGC, Steinbuchel A (2001) Burkholderia sacchari sp. nov., a polyhydroxyalkanoate-accumulating bacterium isolated from soil of a sugar-cane plantation in Brazil. Int J SystEvol Microbiol 51 1709-1713 Brigham CJ, Sinskey AJ (2012) Applications of polyhydroxyalkanoates in the medical industry, frit J Biotechnol Wellness Ind 1 53-60... 

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