Hydrogen and polyhydroxybutyrate production from wheat straw hydrolysate using Caldicellulosiruptor species and Ralstonia eutropha in a coupled process

Research output: Contribution to journalArticle

Abstract

This report presents an integrated biorefinery concept in which wheat straw hydrolysate was treated with co-cultures of osmotolerant thermophilic bacterial strains, Caldicellulosiruptor saccharolyticus and C. owensensis to obtain hydrogen, while the liquid effluent containing acetate and residual glucose was used as feed for polyhydroxybutyrate (PHB) production by Ralstonia eutropha. The Caldicellulosiruptor spp. co-culture consumed 10.8 g/L of pretreated straw sugars, glucose and xylose, producing 134 mmol H2/L. PHB accumulation by R. eutropha was first studied in minimal salts medium using acetate with/without glucose as carbon source. Addition of salts promoted cell growth and PHB production in the effluent. Fed-batch cultivation in a nitrogen limited medium with 40% (v/v) aeration resulted in a cell density of 15.1 g/L with PHB content of 80.1% w/w and PHB concentration of 12.1 g/L, while 20% aeration gave a cell density of 11.3 g/L with 83.4% w/w PHB content and 9.4 g/L PHB concentration.

Details

Authors
Organisations
External organisations
  • Higher University of San Andrés
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Bioenergy

Keywords

  • Caldicellulosiruptor species, Hydrogen, Integrated biorefinery, Polyhydroxybutyrate, Ralstonia eutropha, Wheat straw hydrolysate
Original languageEnglish
Pages (from-to)259-266
Number of pages8
JournalBioresource Technology
Volume272
Publication statusPublished - 2019
Publication categoryResearch
Peer-reviewedYes