2, 3-Butanediol production using Klebsiella oxytoca ATCC 8724: Evaluation of biomass derived sugars and fed-batch fermentation process. (July 2017)

• Record Type: Journal Article
• Authors: Guragain, Yadhu N.; Vadlani, Praveen V.
• Is Part Of: Process biochemistry. Volume 58(2017)
• Page Start: 25
• Page End: 34
• Publication Date: 2017-07
• Subjects: 2, 3-Butanediol -- Lignocellulosic biomass -- Hydrolyzate -- Fed-batch fermentation; Biochemical engineering -- Periodicals; Biotechnology -- Periodicals; Biochemistry -- periodicals; Biotechnology -- periodicals; Chemical Engineering -- periodicals; Génie biochimique -- Périodiques; Biotechnologie -- Périodiques; Biochemical engineering; Biotechnology; Periodicals; 660.63
• DOI: 10.1016/j.procbio.2017.05.001
• Languages: English
• ISSNs: 1359-5113

Abstract

Graphical abstract: Highlights: Sugars derived from energy crops were evaluated for 2, 3-butanediol fermentation. Fed-batch fermentation process was performed to produce high 2, 3-butanediol titer. Mixed sugar medium was less efficient due to carbon catabolite repression. Detoxification of biomass hydrolyzate was needed for efficient fermentation. High 2, 3-butanediol titer (8%) was achieved using single sugar in fed-batch process. Abstract: For this study, 2, 3-butanediol (BD) fermentation from pure and biomass-derived sugar were optimized in shake-flask and 5-L bioreactor levels using Klebsiella oxytoca ATCC 8724. The results showed that 70 g/L of single sugar (glucose or xylose) and 90 g/L of mixed-sugar (glucose:xylose = 2:1) were optimum concentrations for efficient 2, 3-BD fermentation. At optimum sugar concentrations, 2, 3-BD productivities were 1.03, 0.64 and 0.50 gL −1 h −1, and yields were 0.43, 0.36 and 0.35 g/g in glucose, xylose and mixed-sugar medium, respectively. The lack of simultaneous utilization of glucose and xylose led to the lowest productivity in the mixed-sugar medium. Detoxification of biomass hydrolyzates was necessary for efficient 2, 3-BD fermentation when sugar concentrations in the medium was 90 g/L or higher, but not with sugar concentrations of 30 g/L or less. A fed-batch fermentation using glucose medium led to an increase 2, 3-BD titer to 79.4 g/L and yields 0.47 g/g, while productivity decreased to 0.79 gL −1 h −1 . However, the fed-batch process was inefficient using mixed-sugar and biomass hydrolyzates because of poor xylose utilization. These results indicated that appropriate biomass processing technologies must be developed to generate separate glucose and xylose streams to produce high 2, 3-BD titer from biomass-derived sugar using a fed-batch process.