Nutrient optimization for production of polyhydroxybutyrate from halotolerant photosynthetic bacteria cultivated under aerobic-dark condition
Electron. j. biotechnol
; Electron. j. biotechnol;11(3): 83-94, July 2008. ilus, graf, tab
Article
em En
| LILACS
| ID: lil-531890
Biblioteca responsável:
CL1.1
ABSTRACT
Three halotolerant bacterial strains; Rhodobacter sphaeroides ES16 (the wild type) and the two mutant strains of R. sphaeroides ES16, namely N20 and U7, were cultivated in glutamate-malate (GM) medium and screened for production of polyhydroxybutyrate (PHB). The mutant strains N20 and U7 were found to accumulate PHB (53.9 and 42.0 percent of DCW, respectively) 3.6 and 2.8 times higher than the wild type strain (19.5 percent of DCW), respectively. R. sphaeroides N20 were selected for studies on the effects of nutrient and environmental conditions on PHB accumulation. The optimal condition was 4 g/l acetate, 0.02 g/l (NH4)2SO4, C/N ratio of 61, 1.0 g/l K2HPO4, 1.0 g/l KH2PO4 and 3 percent NaCl with initial pH at 7.0. Under this optimal condition, the maximum PHB accumulation increased from 53.9 percent to 88 percent of DCW and 9.11 ± 0.08 g/l biomass, 8.02 +/- 0.10 g/l PHB concentration were achieved after 60 hrs cultivation at 37ºC. These results are the highest values ever obtained from photosynthetic bacteria reported so far.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
LILACS
Assunto principal:
Rhodobacter sphaeroides
/
Bactérias Gram-Negativas Fotossintetizantes Oxigênicas
/
Hidroxibutiratos
Idioma:
En
Revista:
EJB
/
Electron. j. biotechnol
/
Electronic journal of biotechnology
Assunto da revista:
BIOTECNOLOGIA
Ano de publicação:
2008
Tipo de documento:
Article
País de afiliação:
Tailândia
País de publicação:
Chile