Production of Poly-b-Hydroxybutyrate (PHB) by Some Rhizobium Bacteria

Authors : Nazime MERCAN

Pages : 215-219

View : 20 | Download : 7

Publication Date : 2002-12-01

Article Type : Research Paper

Abstract :In this study, the production of Poly-b-hydroxybutyrate insert ignore into journalissuearticles values(PHB); was determined in 1 Rhizobium japonicum, 6 Rhizobium cicer, 8 Rhizobium spp. and Bradyrhizobium japonicum USDA 110. The content of according to dry cell weight was determined to be 1.38-40.0%. In our study, Rhizobium spp. 2426, which produced the highest percentage yield of PHB, and Rhizobium spp. 640, which produced the intermediate percentage yield of PHB, were first selected among all the strains, and then the effect of different carbon and nitrogen sources on PHB production in these strains was tested. While the strains produced less PHB in yeast extract mannitol insert ignore into journalissuearticles values(YEM); broth media with different carbon and nitrogen sources, the highest level of PHB accumulation was observed in the media with L-cysteine and glycine. In this YEM medium with L-cysteine and glycine the percentage of PHB yield of Rhizobium spp. 640 was respectively determined to be 13.40% and 56.67%, while in the same nitrogen sources this percentage in Rhizobium spp. 2426 was determined to be 70% and 61.43%. The Rhizobium spp. 2426 strain capable of PHB accumulation was investigated in YEM with L-cystein at different incubation times insert ignore into journalissuearticles values(between 24 h and 120 h);. The best PHB production and percentage yield of this strain was determined. The PHB production was 0.285 g/l and the percentage yield was 74.03% after 48 h. After this time there was a decrease in PHB yield.
Keywords : Poly b hydroxybutyrate, Biopolymer, Rhizobium, Different carbon and nitrogen sources