One-step process for producing prebiotic arabino-xylooligosaccharides from brewer's spent grain employing Trichoderma species

Food Chem. 2019 Jan 1;270:86-94. doi: 10.1016/j.foodchem.2018.07.080. Epub 2018 Jul 12.

Abstract

Xylooligosaccharides (XOS) are prebiotic nutraceuticals that can be sourced from lignocellulosic biomass, such as agro-residues. This study reports for the first time an optimization study of XOS production from agro-residues by direct fermentation using two Trichoderma species. A total of 13 residues were evaluated as potential substrates for single-step production. The best results were found for Trichoderma reesei using brewers' spent grain (BSG) as substrate. Under optimal conditions (3 days, pH 7.0, 30 °C and 20 g/L of BSG), a production yield of 38.3 ± 1.8 mg/g (xylose equivalents/g of BSG) was achieved. The obtained oligosaccharides were identified as arabino-xylooligosacharides (AXOS) with degree of polymerization from 2 to 5. One-step fermentation proved to be a promising strategy for AXOS production from BSG, presenting a performance comparable with the use of commercial enzymes. This study provides new insights towards the bioprocess integration, enabling further developments of low-cost bioprocesses for the production of these valuable compounds.

Keywords: Agro-residues; Brewers’ spent grain; Prebiotic; Trichoderma; Xxylooligosaccharides.

MeSH terms

  • Edible Grain* / metabolism
  • Edible Grain* / microbiology
  • Fermentation
  • Glucuronates / biosynthesis*
  • Oligosaccharides / biosynthesis*
  • Prebiotics / analysis*
  • Trichoderma / metabolism*

Substances

  • Glucuronates
  • Oligosaccharides
  • Prebiotics
  • xylooligosaccharide