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bioRxiv · 10.1101/2020.03.06.980631

Rapid mechanoenzymatic saccharification of lignocellulosic biomass without bulk water or chemical pre-treatment

Hammerer, F.·Ostadjoo, S.·Dietrich, K.·Dumont, M.-J.·Del Rio, L. F.·Friscic, T.·Auclair, K.
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Abstract

Lignocellulosic material is an abundant renewable resource with the potential to replace petroleum as a feedstock for the production of fuels and chemicals. The large scale deployment of biomass saccharification is, however, hampered by the necessity to use aggressive reagents and conditions, formation of side-products, and the difficulty to reach elevated monosaccharide concentrations in the crude product. Herein we report the high efficacy of Reactive Aging (or Raging, a technique where enzymatic reaction mixtures, without any bulk aqueous or organic solvent, are treated to multiple cycles of milling and aging) for gram-scale saccharification of raw lignocellulosic biomass samples from different agricultural sources (corn stover, wheat straw, and sugarcane bagasse). The solvent-free enzymatic conversion of lignocellulosic biomass was found to proceed in excellent yields (ca. 90%) at protein loadings as low as 2% w/w, without the need for any prior chemical pre-treatment or high temperatures, to produce highly concentrated (molar) monosaccharides. This crude product of mechanoenzymatic depolymerization is non-toxic to bacteria and can be used as a carbon source for bacterial growth.

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Hammerer, F., Ostadjoo, S., Dietrich, K., Dumont, M.-J., Del Rio, L. F., Friscic, T., Auclair, K.. 2020-03-08. Rapid mechanoenzymatic saccharification of lignocellulosic biomass without bulk water or chemical pre-treatment. https://doi.org/10.1101/2020.03.06.980631

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