Enzymatic Conversion of Sugar Beet Pulp: A Comparison of Simultaneous Saccharification and Fermentation and Separate Hydrolysis and Fermentation for Lactic Acid Production

Abstract

SummaryThis study compares the efficiency of lactic acid production by separate hydrolysis and fermentation (SHF) or simultaneous saccharification and fermentation (SSF) of sugar beet pulp (SBP), a by-product of industrial sugar production. In experiments, SBP was hydrolyzed using 5 commercial enzymes. A series of shake flask scale fermentations and was conducted using 5 selected strains of lactic acid bacteria (LAB). The differences in the activities of the enzymes for degrading the principal SBP components were reflected in the different yields of total reducing sugars. The highest yields from hydrolysis and the lowest quantities of insoluble residues were obtained using a mixture (1:1) of Viscozyme and Ultraflo Max. In the SHF process, only a portion of the soluble sugars released by the enzymes from the SBP was assimilated by the LAB strains. In SSF, low enzyme loads revealed reductions in the efficiency of sugar accumulation. The risk of carbon catabolic repression was reduced. Our results suggest www.ftb.com.hrPlease note that this is an unedited version of the manuscript that has been accepted for publication. This version will undergo copyediting and typesetting before its final form for publication. We are providing this version as a service to our readers. The published version will differ from this one as a result of linguistic and technical corrections and layout editing. that SSF has advantages over SHF, including lower processing costs and higher productivity.Lactic acid yield in SSF mode (around 30 g/L) was 80-90 % higher than that for SHF.

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The Use of Acidic Hydrolysates after Furfural Production from Sugar Waste Biomass as a Fermentation Medium in the Biotechnological Production of Hydrogen

“…These monosaccharides can successfully be used as sources of sugars for microorganisms (e.g., lactic acid bacteria, yeasts, fungi, etc.) [8][9][10][11] or as substrates in chemical syntheses, e.g., for the production of fuels (bioethanol, methane, hydrogen), solvents, polymers, etc. [4,[12][13][14].…”

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