Lignocellulosic biomass is a renewable, low cost, non-food and abundant feedstock for biofuel production and a source of C atoms for chemistry alternative to fossil resources. The most important factor hampering massive exploitation of cellulose, the main component of plant biomass, is its well known low reactivity and recalcitrance towards chemical processing. The usual steps in producing biofuels from cellulosic sources are: pre-treatment followed by cellulose precipitation, enzymatic hydrolysis and fermentation. Pre-treatment of cellulose is a necessary step in the production of ethanol from cellulosic material since it makes the recalcitrant cellulosic biomass more accessible to enzymatic hydrolysis. A possible greener alternative for the activation of cellulose fibrilles towards facile hydrolysis and/or derivatization passes through an emerging chemical pre-treatment step using ionic liquids (ILs). Unlikely, the more common cellulases have been reported to be inactivated by ILs. In this work we describe a single-batch, homogeneous phase enzymatic depolymerization of cellulose catalyzed by a commercial cellulase (EC 3.2.1.4) in the presence of different ILs. In fact the industrial enzymatic preparation IndiAge(R) Super GX Plus (a mono-component endoglucanase EGIII (Cel12A) from Trichoderma reesei produced by Genencor Intl) has been already tested in our previous work in the presence of a commercial IL, 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]). Interestingly, this enzyme showed exceedingly good performance for the depolymerization of dissolved cellulose in [BMIM][Cl] without the usual pretreatment, known as dissolution-regeneration of cellulose in its amorphous form.Then we moved towards the possibility of using two more friendly ILs such as 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) and diethylphosphate ([EMIM][DEP] and the present study presents a useful comparison of the effect on stability and activity of IndiAge(R) Super GX Plus in these media. We believe that this strategy could be amenable of scale-up and innovative industrial applications for the efficient one-batch conversion of inexpensive cellulosic materials into derivatives (biofuels, derivatized cellulose, monosaccharides for fine chemicals, etc.) with high potential commercial interest and in the framework of environmentally friendly chemistry.
Depolymerization of Cellulose in Ionic Liquids
W Panzeri;
2015
Abstract
Lignocellulosic biomass is a renewable, low cost, non-food and abundant feedstock for biofuel production and a source of C atoms for chemistry alternative to fossil resources. The most important factor hampering massive exploitation of cellulose, the main component of plant biomass, is its well known low reactivity and recalcitrance towards chemical processing. The usual steps in producing biofuels from cellulosic sources are: pre-treatment followed by cellulose precipitation, enzymatic hydrolysis and fermentation. Pre-treatment of cellulose is a necessary step in the production of ethanol from cellulosic material since it makes the recalcitrant cellulosic biomass more accessible to enzymatic hydrolysis. A possible greener alternative for the activation of cellulose fibrilles towards facile hydrolysis and/or derivatization passes through an emerging chemical pre-treatment step using ionic liquids (ILs). Unlikely, the more common cellulases have been reported to be inactivated by ILs. In this work we describe a single-batch, homogeneous phase enzymatic depolymerization of cellulose catalyzed by a commercial cellulase (EC 3.2.1.4) in the presence of different ILs. In fact the industrial enzymatic preparation IndiAge(R) Super GX Plus (a mono-component endoglucanase EGIII (Cel12A) from Trichoderma reesei produced by Genencor Intl) has been already tested in our previous work in the presence of a commercial IL, 1-butyl-3-methylimidazolium chloride ([BMIM][Cl]). Interestingly, this enzyme showed exceedingly good performance for the depolymerization of dissolved cellulose in [BMIM][Cl] without the usual pretreatment, known as dissolution-regeneration of cellulose in its amorphous form.Then we moved towards the possibility of using two more friendly ILs such as 1-ethyl-3-methylimidazolium acetate ([EMIM][Ac]) and diethylphosphate ([EMIM][DEP] and the present study presents a useful comparison of the effect on stability and activity of IndiAge(R) Super GX Plus in these media. We believe that this strategy could be amenable of scale-up and innovative industrial applications for the efficient one-batch conversion of inexpensive cellulosic materials into derivatives (biofuels, derivatized cellulose, monosaccharides for fine chemicals, etc.) with high potential commercial interest and in the framework of environmentally friendly chemistry.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
