Biosynthesis of poly(3-hydroxybutyrate-co-4-hydroxybutyrate) copolymer by Cupriavidus sp. USMAA1020 isolated from Lake Kulim, Malaysia.
Bioresour Technol
; 99(11): 4903-9, 2008 Jul.
Article
em En
| MEDLINE
| ID: mdl-17981028
ABSTRACT
Cupriavidus sp. USMAA1020 was isolated from Malaysian environment and able to synthesize poly(3-hydroxybutyrate-co-4-hydroxybutyrate), [P(3HB-co-4HB)] when grown on gamma-butyrolactone as the sole carbon source. The polyester was purified from freeze-dried cells and analyzed by nuclear magnetic resonance (NMR) spectroscopy. 1H and 13C NMR results confirmed the presence of 3HB and 4HB monomers. In a one-step cultivation process, P(3HB-co-4HB) accumulation by Cupriavidus sp. USMAA1020 was affected by carbon to nitrogen ratio (C/N). A two-step cultivation process accumulated P(3HB-co-4HB) copolyester with a higher 4HB fraction (53 mol%) in nitrogen-free mineral medium containing gamma-butyrolactone. The biosynthesis of P(3HB-co-4HB) was also achieved by using 4-hydroxybutyric acid and alkanediol as 1,4-butanediol. The composition of copolyesters varied from 32 to 51 mol% 4HB, depending on the carbon sources supplied. The copolyester produced by Cupriavidus sp. USMAA1020 has a random sequence distribution of 3-hydroxybutyrate (3HB) and 4-hydroxybutyrate (4HB) units when analyzed by nuclear magnetic resonance (NMR) spectroscopy. When gamma-butyrolactone was used as the sole carbon source, the 4HB fraction in copolyester increased from 25 to 60 mol% as the concentration of gamma-butyrolactone in the culture medium increased from 2.5 g/L to 20.0 g/L.
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Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Poliésteres
/
Cupriavidus
/
Água Doce
/
Hidroxibutiratos
País/Região como assunto:
Asia
Idioma:
En
Ano de publicação:
2008
Tipo de documento:
Article