Abstract
BackgroundBiomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides. Lignocellulosic feedstocks often require physicochemical pretreatment before enzymatic hydrolysis can begin. The optimal pretreatment can be different for different feedstocks, and should not lead to biomass destruction or formation of toxic products.MethodsWe examined the influence of six mild sulfuric acid or water pretreatments at different temperatures on the enzymatic degradability of sugar-beet pulp (SBP).ResultsWe found that optimal pretreatment at 140°C of 15 minutes in water was able to solubilize 60% w/w of the total carbohydrates present, mainly pectins. More severe treatments led to the destruction of the solubilized sugars, and the subsequent production of the sugar-degradation products furfural, hydroxymethylfurfural, acetic acid and formic acid. The pretreated samples were successfully degraded enzymatically with an experimental cellulase preparation.ConclusionsIn this study, we found that pretreatment of SBP greatly facilitated the subsequent enzymatic degradation within economically feasible time ranges and enzyme levels. In addition, pretreatment of SBP can be useful to fractionate functional ingredients such as arabinans and pectins from cellulose. We found that the optimal combined severity factor to enhance the enzymatic degradation of SBP was between log R'0 = -2.0 and log R'0 = -1.5. The optimal pretreatment and enzyme treatment solubilized up to 80% of all sugars present in the SBP, including ≥90% of the cellulose.
Highlights
Biomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides
Mass of pretreated Sugar-beet pulp (SBP) The effects of the different pretreatments on the solubilization of SBP were evaluated by weighing on a mass balance, taking into account the respective amounts of solubilized, residual and decomposed material
We found that the combination of a mild hydrothermal pretreatment at 140°C with subsequent enzymatic digestion allowed fast and efficient hydrolysis of SBP
Summary
Biomass use for the production of bioethanol or platform chemicals requires efficient breakdown of biomass to fermentable monosaccharides. Sugar-beet pulp (SBP) consists of up to 75% w/w of carbohydrates (dry matter). The pressed pulp has a dry-matter content of 18-23% w/w. The low dry-matter content makes combustion of SBP for heat and power production unfavorable; its low lignin and high sugar. The cell-wall material needs to be degraded into fermentable monosaccharides To this end, lignocellulosic feedstocks are often structurally modified by a mild pretreatment before enzymatic release of fermentable monosaccharides [5]. Lignocellulosic feedstocks are often structurally modified by a mild pretreatment before enzymatic release of fermentable monosaccharides [5] The severity of this pretreatment can be measured by a combined severity factor (log R′′0) that takes into account pretreatment time, pretreatment temperature, and acid concentration (w/w%)
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
