Poly P-hydroxyalkanoate s

Another interesting example of lactones are the p-hydroxyalkanoates, whose ROP affords poly(p-hydroxyalkanoate)s (PHAs), a class of aliphatic polyesters naturally produced by bacteria (Fig. 3) [12, 13]. Poly(3-(R)-hydroxybutyrate) (PHB) is a typical example. PHB is a stiff thermoplastic material with relatively poor impact strength, but the incorporation of other monomers can improve the mechanical properties. 

Many bacteria are a potential source of naturally occurring polyesters, mainly poly (P-hydroxyalkanoate)s with a general structure... 

Chromatography Poly(P-hydroxyalkanoate)s Chromatography Tetrahydrofiiran Chloroform SEC, styragel SEC, styragel -i- ulbastyragel SEC, ultrastyragel SEC, p-styragel, 25°C 1814 1678 1254 3384... 

Aliphatic polyesters are the most representative examples of biodegradable polymeric materials. Poly(3-hydroxyalkanoate)s, PHA, are well known biocompatible and biodegradable polyesters that are produced by various microorganisms as carbon and energy reserves. The physical properties of PHAs vary from crystalline-brittle to soft-sticky materials depending on the length of the side aliphatic chain on p carbon ... 

Green PR, Kemper J, Lee S, Guo L, Satkowski M, Fiedler S, Stembiichel A, Rehm BHA (2002) Formation of short chain length/medium chain length polyhydroxyalkanoate copolymers by fatty acid oxidation inhibited Ralstonia eutropha. Biomacromolecules 3 208—213 Gross RA, DeMeUo C, Lenz RW, Brandi H, Fuller RC (1989) Biosynthesis and characterization of poly(P-hydroxyalkanoates) produced by Pseudomonas oleovorans. Macromolecules 22 1106-1115... 

Gilmore DF, Antoun S, Lenz RW, Fuller RC (1993) Degradation of poly(p-hydroxyalkanoates) and polyolefin blends in a municipal wastewater treatment facility. J Environ Polym Degr 1 269-274... 

P. Furrer, S. Panke, M. Zinn, Efficient recovery of low endotoxin medium-chain-length poly ([R]-3-hydroxyalkanoate) from bacterial biomass, J. Microbiol. Methods 69 (1) (2007) 206-213. 

Bear, M. M., Leboucherdurand, M. A., Langlois, V., Lenz, R. W., Goodwin, S., and Guerin, P., 1997, Bacterial Poly-3-Hydroxyalkanoates with Epoxy Groups in the Side-Chains. React. Funct. Polymers 34 65... 

Kowalczuk, M., Adamus, G., Sikorska, W., Htkzer, B., Borcakli, M., Atkin, A.H., 2000, Novel biodegradable packaging materials based upon atactic poly[(R,S)-3-hydroxybutyrate] and natural poly(hydroxyalkanoate)s, Proc. International Food Biopack Conference , Copenhagen, p. 39. 

Sun Z, Ramsay JA, Guay M, Rtunsay BA (lOCfl) Fermentation process development for the production of medium-chain-length poly-3-hydroxyalkanoates. Appl Microbiol Biotechnol 75 475-485 Suriyamongkol P, Weselake R, Narine S, Moloney M, Shah S (2(X)7) Biotechnological approaches for the production of polyhydroxyalkanoates in microoigtmisms and plants - a review. Biotechnol Adv 25 148—175... 

Zhang LL, Xiong CD, Deng XM (1997b) MisdbUity, crystallization and morphology of poly(P-hydroxybutyrate)/poly(D,L-lactide) blends. Polymer 37 235-241 Zhang S, Kolvek S, Goodwin S, Lenz RW (2(X)4) Poly(hydroxyalkanoic add) biosynthesis in Ectothiorhodospira shaposhnikovii characterization and reactivity of the type 111 Pha synthase. Biomacromolecules 5 40-48... 

Huisman GW, Wonink E, Meima R, Kazemier B, Terpstra P, Witholt B (1991) Metabolism of poly(3-hydroxyalkanoates) (PHAs) by Pseudomonas oleovorans. J Biol Chem 266 2191-2198 II Yun S, Gadd GE, LateUa BA, Lo V, Russell RA, Holden PJ (2008) Mechanical properties of biodegradable polyhydroxyalkanoates/single wall carbon nanotube nanocomposite films. Polym Bull 61 267-275... 

Biodegradable polymers can be classified into three categories according to their origin (i) synthetic polymers, particularly aUphatic polyesters, such as poly (L-lactide) (PLA) [1-3], poly(e-caprolactone) (PCL) [4—6], poly(p-dioxanone) (PPDO) [7-9], and poly(butylene succinate) (PBS) [10-12] (ii) polyesters produced by microorganisms, which mainly correspond to different poly(hydroxyalkanoate)s (e.g., poly(P-hydroxybutyrate) and poly(3-hydroxybutyrate-co-3-hydroxyvalerate)) and (iii) polymers derived from natural resources (e.g., starch, cellulose, chitin, chitosan, lignin, and proteins). 

Nodax poly(3-hydroxybutyrate-co- 3-hydroxyalkanoate)s Kaneka/P G Japan www.nodax.com... 

Gudrin P, Renard E, Langlois V. Degradation of natural and artificial poly[(R)-3-hydroxyalkanoate]s from biodegradation to hydrolysis. In Chen GQ, editor. Plastics From Bacteria—Natural Functions and Applications. Berlin Springer 2010. p 283-321. 

Poly(hydroxyalkanoate)s can be prepared from a large range of bacteria, e.g., the system poly(hydroxybutanoate)/T/ca%ene eutrophus A. eutrophus) was extensively studied. On the other hand, medium-sized poly(hydroxyalkano-ate)s were essentially prepared by Pseudomonas oleovorans P. oleovorans). 

When P. oleovorans is used, the type of poly (hydroxyalkanoate)s essentially depends on the nature of the carbon source. For instance, when the substrate is octanoic acid, the product is a random copolymer containing 89 mole% of C8 units and 11 mole% of C6 units. On the other hand, dodecanoic acid generates copolymers containing C12 (31 mole%), CIO (36 mole%), C8 (31 mole%), and C6 (2 mole%) units [89],... 

Lageveen R G, Huisman G W, Preusting H, Ketelaar P, Eggink G and Withold B (1988) Formation of polyesters by Pseudomonas oleovorans effect of substrates on formation and composition of poly[(-R)-3-hydroxyalkanoate]s and poly[(-R)-3-hyd-roxyalkenoatejs, Appl Environ Microbiol 54 2924-2932. 

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