Saccharification of ozonated sugarcane bagasse using enzymes from Myceliophthora thermophila JCP 1-4 for sugars release and ethanol production

Abstract

The saccharification of ozonated sugarcane bagasse (SCB) by enzymes from Myceliophthora thermophila JCP 1-4 was studied. Fungal enzymes provided slightly higher sugar release than commercial enzymes, working at 50°C. Sugar release increased with temperature increase. Kinetic studies showed remarkable glucose release (4.99 g/L, 3%w/w dry matter) at 60°C, 8 h of hydrolysis, using an enzyme load of 10 FPU (filter paper unit). FPase and β-glucosidase activities increased during saccharification (284% and 270%, respectively). No further significant improvement on glucose release was observed increasing the enzyme load above 7.5 FPU per g of cellulose. Higher dry matter contents increased sugars release, but not yields. The fermentation of hydrolysates by Saccharomyces cerevisiae provided glucose-to-ethanol conversions around to 63%.

Cellulases and xylanases production by endophytic fungi by solid state fermentation using lignocellulosic substrates and enzymatic saccharification of pretreated sugarcane bagasse

“…For model validation, three saccharification experiments were performed under the predicted optimum conditions, glucose and xylose concentrations in the hydrolysates were 3.56 ± 0.08 and 1.66 ± 0.11 mg mL −1 , respectively, indicating that the model proposed has successfully modeled the saccharification of pretreated sugarcane bagasse in the present study. Glucose and xylose concentrations obtained in the present study were close to those cited by Pereira et al (2016) in the saccharification of ozonated sugarcane bagasse using the commercial enzymes Celluclast 1.5 L and Novozym 188 or the enzymatic extract from Miceliophthora thermophila JCP 1-4. Maitan-Alfenas et al (2016) and Qu et al (2017) also cited similar xylose concentrations in the hydrolysates obtained at approximately 24 h of saccharification of sugarcane bagasse submitted to alkaline pretreatment, using commercial enzymes.…”

“…Cellulases especially have received attention in recent years, since they are used to saccharify cellulose of lignocellulosic materials releasing glucose that can be converted into cellulosic ethanol by fermenting microorganisms. Cellulosic ethanol is reported as the best alternative biofuel to be used as a substitute for fossil fuels, which besides not being renewable cause environmental impacts from its combustion (Raj and Krishnan, 2018;Nguyen et al, 2017;Harris et al, 2014;Pereira et al, 2016). Xylanases hydrolyze xylan, the main hemicellulosic polysaccharide, which associated to other hemicelluloses components binds to the surface of cellulose microfibrils by hydrogen bonding and hinders cellulase action during saccharification (Farinas et al, 2008).…”

Effect of Metal Ions, Chemical Agents and Organic Compounds on Lignocellulolytic Enzymes Activities

“…3.2.1.4) hydrolyze the amorphous fraction of cellulose, releasing cellodextrins and cello-oligosaccharides [22] decreasing the substrate polymerization degree. They are classified into 11 families of glycosil-hydrolases: GH 5,6,7,8,9,12,44,45,48,51,and 74 [23]. Some endoglucanases have affinity with others substrates, besides cellulose, such as xyloglucan, xylan, and mannan [24].…”

“…The addition of xylanase to the reaction media is an alternative to remove these products [60]. The inhibition of β-glycosidases activities by glucose is frequently observed [6,61]. Disaccharides such as cellobiose and xylobiose, and monosaccharides such as mannose and galactose can inhibit some exoglucanases activities [22,59,62].…”

“…Cellulases are employed in many industrial sectors, such as textile [1], detergents [2], animal feed, and vinification [2][3][4][5]. In the last years, the potential of these enzymes to saccharify cellulose from lignocellulosic residues has been extensively studied aiming the use of glucose for cellulosic ethanol production [6]. Hemicellulases are used in biobleaching of Kraft pulp for paper production [7,8], bioclarification of fruit juices [9], and obtainment of C5 and C6 sugars from lignocellulosic residues, in the context of second-generation ethanol production [10].…”