The increasing global demand for sustainable resources necessitates the complete utilization of feedstock. Wheat bran consists of significant amount of cellulose and hemicellulose which can be used as a renewable resource for production of fermentable sugars. In this study, alkaline pretreated wheat bran was enzymatically hydrolyzed using cellulase of Trichoderma reesei (37 FPU/g) and β - glucosidase of Aspergillus niger (50 CBU/g). Among the nitrogen sources tested, ammonium sulphate was identified as best nitrogen source for the production of polyhydroxybutyrate (PHB). The overall sugar concentration was about 62.91g/L with the corresponding sugar yield of 629.1mg/g wheat bran and the sugars released were mainly composed of glucose (48.35g/L) and xylose (14.56g/L). The PHB producing mutant strain, Ralstonia eutropha NCIMB 11599 grown in wheat bran hydrolysate produced cell density, PHB and yield of 24.5g/L, 62.5%, and 0.319g/g sugar respectively, with a productivity of 0. 0.255g/L/h. Thus, the results suggested that the wheat bran could be a potential alternative feedstock as it does not require any detoxification due to less inhibitory compounds for production of high cell density with significant amount of polyhydroxybutyrate.
Keywords: Enzymatic hydrolysis; Lignocellulosic biomass; Polyhydroxybutyrate; Ralstonia eutropha; Wheat bran.
Copyright © 2016 Elsevier B.V. All rights reserved.