Production of poly-ß-hydroxybutyric acid by Rhizobium sp.

Abstract

The plastic materials produced from petroleum based chemicals cause serious environmental waste problems all over the world when they are discarded after use. As an answer for this environmental anxiety, the usage of biodegradable plastic materials should be preferred. Poly-p-hydroxybutync acid (PHB) is one of the biodegradable polymeric materials and has many characteristics of traditional plastics. In this study, the PHB production ability of Rhizobium bacteria was investigated. The bacteria were isolated from nodule of leguminous roots. The yield percentages of PHB produced by 27 strains of the Rhizobium bacteria were between 4.40%-27.80%. The yields were determined for five strains grown under different carbon and nitrogen sources and varied from 10.00% to 27.80% for carbon sources and from 10.00% to 17.70% for nitrogen sources. The strains R15 and R17 gave the highest yield in the production of PHB. With different shaking velocities, the yield percentages obtained were varied from 21.60 to 28.70