Cellulose enzymatic saccharification

Water used in this supercritical state behaves very differently from water under normal pressure and temperare." In such a supercritical state, the water can be expected to act as an acid or base, but by returning the system to ordinary conditions before pyrolysis occurs, glucose and its derivatives could be obtained in water from cellulose. Therefore, supercritical water treatment can be superior to enzymatic saccharification or oidinaiy acid hydrolysis mentioned above, for the chemical conversion of biomass to useful chemicals. 

Enzymatic Saccharification of Cellulose in Semi-and Continously Agitated Systems... 

Fig. 6. Glucose and cellobiose inhibition of enzymatic saccharification of cellulose. <25p cellulose (Solka Floe) in 10 ml tubes, agitated, O-O-O-O-control, A-A-A-A-control + 5mg/ml of cellobiose, - - -control +10 mg/ml of d-glucose. Reaction time —10 min. Temp. — 50° C, Cellulase —1.86 FP...

From the data on pure and crude cellulose saccharification presented in the paper it is evidenced that the initial enzymatic saccharification of cellulose is of pseudo first order and is therefore represented by... 

The enzymatic saccharification of cellulose is a product inhibited system. The Linewearer Burk model is ... 

Puri, V.P. Effect of crystallinity and degree of polymerization of cellulose on enzymatic saccharification. Biotechnol. Bioeng. 26(10), 1219-1222 (1984)... 

The methods for saccharification of cellulose include acid saccharification and enzymatic saccharification. 

Dawson L, Boopathy R. (2008). Cellulosic ethanol production from sugarcane bagasse without enzymatic saccharification. BioResources, 3, 452-460. 

Griggs AJ, Stickel JJ, Lischeske JJ. (2012a). A mechanistic model for enzymatic saccharification of cellulose using continuous distribution kinetics I depolymerization by EGI and CBHI. Biotechnol Bioeng, 109(3), 665-675. 

US 0.29/L and US 0.53/L, respectively (Balat, 2011). In 2011, NREL (Colorado, USA) published the detailed report Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol (Humbird et al.. Mar. 2011). The NREL process design converts corn stover to ethanol by dilute-acid pretreatment, enzymatic saccharification, and co-fermentation, and with a minimum ethanol selling price (MESP) of US 2.15/gal (US 0.57/L calculated) by 2012 conversion targets (Table 7.3). In the report, the biomass amount processed is 2205 dry ton/day at 76% theoretical ethanol yield (79 gal/dry ton). It is expected that this MESP will become the standard for the cost of cellulosic bioethanol. 

Henley R G, Yang R Y K, Greenfield P F, (1980), Enzymatic saccharification of cellulose in membrane reactors. Enzyme Microbial Technology, 2,206-208. 

Alfani, F., Albanesi, D., Cantarella, M., Scardi, V., Vetromile, A. (1982). Kinetics of enzymatic saccharification of cellulose in a fiat-membrane reactor. Biomass, 2, 245—253. 

The bioconversion of cellulose into ethanol with conventional methods is usually achieved in two steps first being the enzymatic saccharification of the polysaccharide to monosaccharide and secondly the bioconversion of monosaccharides into ethanol. A combination of enzymatic hydrolysis and ethanol production in the same reactor has been attempted using different cellulases and ethanol producing microbial species to improve process efficiency [46-53]. The production of ethanol from cellulose in a simultaneous saccharification and biological conversion process alleviates the problem of end product inhibition, since glucose does not accumulate in this system and is converted to ethanol immediately following saccharification [46]. 

Arantes and Saddler 2010 Baneijee et al. 2010 Gao et al. 2010 Moreira et al. 2011). The role of amorphogenesis in the initial stage of enzymatic saccharification of cellulose is to non-hydrolytically loosen or disrupt the cellulose fibril network (Arantes and Saddler 2010). 

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