The production of lignocellulosic ethanol is one of the most promising alternatives to fossil fuels, however, this technology still faces many challenges related to the viability of the alcohol in the market. In this paper the endocarp of buriti fruit was assessed for ethanol production. The whole fruit was characterized physically and chemically and its endocarp submitted to acid and alkaline pre-treatments, which were optimized through the use of surface response methodology for removal of hemicellulose and lignin, respectively. Abstract 16 The production of lignocellulosic ethanol is one of the most promising alternatives to fossil fuels, 17 however, this technology still faces many challenges related to the viability of the alcohol in the 18 market. In this paper the endocarp of buriti fruit was assessed for ethanol production. The whole 19 fruit was characterized physically and chemically and its endocarp submitted to acid and alkaline 20 pre-treatments, which were optimized through the use of surface response methodology for 21 removal of hemicellulose and lignin, respectively. Hemicellulose content was reduced by 88% 22 after acid pretreatment. Alkaline pre-treatment reduced the lignin content in the recovered 23 biomass from 11.8% to 4.2% and increased the concentration of the cellulosic fraction to 88.5%. 24 The pre-treated biomass was saccharified by the action of cellulolytic enzymes and, in the 25 optimized condition, was able to produce 110 g of glucose per L of hydrolyzate. Alcoholic 26 fermentation of the enzymatic hydrolyzate bio-catalized by Saccharomyces cerevisiae resulted in 27 a fermented medium with 4.3% ethanol and Y P/S of 0.33 . The current configuration of global economic advance has created a growing demand for 33 energy resources to support its maintenance. Additionally, the growth of the human population 34 on the planet, the depletion of fossil fuels and the growing concerns about human impacts on the 35 environment have encouraged the search for renewable sources to the development of green 36 energy production (Singh, Nigam & Murphy, 2011; Sarkar et al., 2012). In this context, 37 lignocellulosic biomasses are a promising feedstock for the production of liquid biofuels, 38 alternative to petroleum based fuels (Cherubini & Ulgiati, 2010). 39The technology for the production of second generation (2G) bioethanol, or 40 lignocellulosic ethanol, has evolved in the last decades and functioning industrial plants already 41 exist in some parts of the world, nevertheless, this biofuel still faces the challenge of feedstock 42 access, supply chain infrastructure, and price competitiveness with the petroleum industry (UNCTAD, 43 2016). 44Lignocellulosic ethanol can be obtained from the fermentation of hexoses and pentoses 45 derived from the polysaccharides that constitute the plants cell wall and require additional 46 operations to those normally used to produce first generation ethanol (Mielenz, 2001). Lignin 47 removal and hemicellulose hydrolysis, followed by cellulose saccharif...

The production of lignocellulosic ethanol is one of the most promising alternatives to fossil fuels; however, this technology still faces many challenges related to the viability of the lignocellulosic alcohol in the market. In this paper the endocarp of buriti fruit was assessed for ethanol production. The fruit endocarp was characterized physically and chemically. Acid and alkaline pre-treatments were optimized by surface response methodology for removal of hemicellulose and lignin from the biomass. Hemicellulose content was reduced by 88% after acid pretreatment. Alkaline pre-treatment reduced the lignin content in the recovered biomass from 11.8% to 4.2% and increased the concentration of the cellulosic fraction to 88.5%. The pre-treated biomass was saccharified by the action of cellulolytic enzymes and, under optimized conditions, was able to produce 110 g of glucose per L of hydrolyzate. Alcoholic fermentation of the enzymatic hydrolyzate performed by Saccharomyces cerevisiae resulted in a fermented medium with 4.3% ethanol and a yield of product per substrate (YP/S) of 0.33.

The production of lignocellulosic ethanol is one of the most promising alternatives to fossil fuels, however, this technology still faces many challenges related to the viability of the alcohol in the market. In this paper the endocarp of buriti fruit was assessed for ethanol production. The whole fruit was characterized physically and chemically and its endocarp submitted to acid and alkaline pre-treatments, which were optimized through the use of surface response methodology for removal of hemicellulose and lignin, respectively.Hemicellulose content was reduced by 88% after acid pretreatment. Alkaline pretreatment reduced the lignin content in the recovered biomass from 11.8% to 4.2% and increased the concentration of the cellulosic fraction to 88.5%. The pre-treated biomass was saccharified by the action of cellulolytic enzymes and, in the optimized condition, was able to produce 110 g of glucose per L of hydrolyzate. Alcoholic fermentation of the enzymatic hydrolyzate bio-catalized by Saccharomyces cerevisiae resulted in a fermented medium with 4.3% ethanol and Y P/S of 0.33 .PeerJ Preprints | https://doi.org/10.7287/peerj.preprints.26777v1 | CC BY 4.0 Open Access | recAbstract 16 The production of lignocellulosic ethanol is one of the most promising alternatives to fossil fuels, 17 however, this technology still faces many challenges related to the viability of the alcohol in the 18 market. In this paper the endocarp of buriti fruit was assessed for ethanol production. The whole 19 fruit was characterized physically and chemically and its endocarp submitted to acid and alkaline 20 pre-treatments, which were optimized through the use of surface response methodology for 21 removal of hemicellulose and lignin, respectively. Hemicellulose content was reduced by 88% 22 after acid pretreatment. Alkaline pre-treatment reduced the lignin content in the recovered 23 biomass from 11.8% to 4.2% and increased the concentration of the cellulosic fraction to 88.5%. 24 The pre-treated biomass was saccharified by the action of cellulolytic enzymes and, in the 25 optimized condition, was able to produce 110 g of glucose per L of hydrolyzate. Alcoholic 26 fermentation of the enzymatic hydrolyzate bio-catalized by Saccharomyces cerevisiae resulted in 27 a fermented medium with 4.3% ethanol and Y P/S of 0.33 . 28 29