Biomass deconstruction methods

While the main goal of this chapter has been to highlight the role that ethanol has played in the development of the metabolic engineering field, the latter has also played a similar role in the development of biomass deconstruction methods. Here we discuss examples of biomass deconstruction techniques that were first demonstrated with ethanol production but have since been extrapolated to other biorenewable fuels and chemicals. 

A variety of methods have been demonstrated for biomass deconstruction. These can be broadly classified as chemical, biological, physical, and physicochemical [155]. Chemical methods include steam, lime, liquid hot water, ionic liquids, organosolve, ammonia, oxidative delignification, and ozonolysis [150, 155]. Physical and physiochemical methods include milling, steam explosion (autohydrolysis), ammonia fiber explosion (AFEX), microwave, extrusion, pulsed electric field, pyrolysis, and ultrasound. Consistent with the theme of this chapter, the first description of a novel non-enzymatic biomass deconstruction technique demonstrated the effectiveness of this method by producing ethanol [156]. 

NMR spectroscopy is a well-established analytical technique in biofuel research. Over the past few decades, lignocellulosic biomass and its conversion to supplement or displace non-renewable feedstocks has attracted increasing interest. The application of solid-state NMR spectroscopy has long been seen as an important tool in the study of cellulose and lignocellulose structure, biosynthesis, and deconstruction, especially considering the limited number of effective solvent systems and the significance of plant cell wall three-dimensional microstructure and component interaction to conversion yield and rate profiles. The article by Foston reviews common and recent applications of solid-state NMR spectroscopy methods that provide insight into the structural and dynamic processes of cellulose that control bulk properties and biofuel conversion. 

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