Sustainable production of xylonic acid from acid pre-treated sawdust liquor and subsequent downstream processing

Abstract

Xylonic acid is a versatile and valuable chemical with a range of industrial and potential health applications. The high demand for renewable energy and sustainable products has increased interest in xylonic acid as a starting material for the production of variety of high value chemicals and biofuels. The production of xylonic acid from biomass have an added advantage that it provides an opportunity to utilize bio-waste materials that would otherwise be discarded, reducing environmental hazards and reducing waste disposal costs. The aim of this research was to establish a bioprocess for producing xylonic acid from acid pre-treated sawdust liquor via fermentation, utilizing metabolically engineered strain of Corynebacterium glutamicum ATCC 31831. A maximum titre of 48.5 ± 0.2 g/L xylonic acid from 60 g/L xylose derived from biomass was obtained with a yield of 0.89 g/g xylose which corresponds to a conversion of 62%. 30.8 ± 0.4 g/L of xylonic acid crystals of 95.5% purity were successfully recovered from 1L sawdust APL (Acid Pre-treated Liquor) via solvent precipitation and crystallization. Purified xylonic acid crystals were checked for its antibacterial effect on Salmonella enterica MTCC 3224, Escherichia coli MTCC 443 and Staphylococcus aureus MTCC 96.

Funding

CSIR New Delhi,(SRF)