title: Furfural and glucose can enhance conversion of xylose to xylitol by Candida magnoliae TISTR 5663.
abstract: Xylitol production from xylose by the yeast Candida magnoliae TISTR 5663 was enhanced by supplementing the fermentation medium with furfural (300mg/L) and glucose (3g/L with an initial mass ratio of glucose to xylose of 1:10) together under oxygen limiting conditions. In the presence of furfural and glucose, the final concentration of xylitol was unaffected relative to control cultures but the xylitol yield on xylose increased by about 5%. Supplementation of the culture medium with glucose alone at an initial concentration of 3g/L, stimulated the volumetric and specific rates of xylose consumption and the rate of xylitol production from xylose. In a culture medium containing 30g/L xylose, 300mg/L furfural and 3g/L glucose, the volumetric production rate of xylitol was 1.04g/L h and the specific production rate was 0.169g/g h. In the absence of furfural and glucose, the volumetric production rate of xylitol was ∼35% lower and the specific production rate was nearly 30% lower. In view of these results, xylose-containing lignocellulosic hydrolysates contaminated with furfural can be effectively used for producing xylitol by fermentation so long as the glucose-to-xylose mass ratio in the hydrolysate does not exceed 1:10 and the furfural concentration is ≤300mg/L.
authors.affiliation: Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok 10900, Thailand; Center for Advanced Studies in Tropical Natural Resources (CASTNAR), National Research University-Kasetsart University (NRU-KU), Kasetsart University, Bangkok 10900, Thailand.
authors.forename: Siwaporn
authors.initials: S
authors.lastname: Wannawilai
authors.affiliation: Department of Chemical Engineering, National Chung Cheng University, Minhsiung 621, Taiwan.
authors.forename: Wen-Chien
authors.initials: WC
authors.lastname: Lee
authors.affiliation: School of Engineering, Massey University, Private Bag 11 222, Palmerston North, New Zealand.
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Chisti
authors.affiliation: Department of Biotechnology, Faculty of Agro-Industry, Kasetsart University, Bangkok 10900, Thailand; Center for Advanced Studies in Tropical Natural Resources (CASTNAR), National Research University-Kasetsart University (NRU-KU), Kasetsart University, Bangkok 10900, Thailand. Electronic address: sarote.s@ku.ac.th.
authors.forename: Sarote
authors.initials: S
authors.lastname: Sirisansaneeyakul
mesh_terms: D019149:Bioreactors / Q000382:microbiology*; D002175:Candida / Q000378:metabolism*; D005285:Fermentation; D005662:Furaldehyde / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D014993:Xylitol / Q000032:analysis / Q000378:metabolism*; D014994:Xylose / Q000378:metabolism*
chemical_list: D014994:Xylose; D005662:Furaldehyde; D005947:Glucose; D014993:Xylitol
keywords: Candida magnoliae; Fermentation; Furfural; Glucose; Xylitol; Xylose