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Effect of extruder screw speed, temperature, and enzyme levels on sugar recovery from different biomasses.

Karunanithy C, Muthukumarappan K, Gibbons WR - ISRN Biotechnol (2012)

Bottom Line: Biofuels from biomass have the potential to reduce the dependency on fossil fuels.Screw speed, barrel temperature, and their interaction had a significant influence on sugar recovery from the selected biomasses.Extrusion pretreatment of these biomasses used only 28-37% of the rated extruder power.

View Article: PubMed Central - PubMed

Affiliation: Department of Agricultural Biosystems Engineering, South Dakota State University, 1400 North Campus Drive, Brookings, SD 57007, USA.

ABSTRACT
Biofuels from biomass have the potential to reduce the dependency on fossil fuels. An efficient pretreatment method is required to accomplish the target of the Energy Act 2005. Extrusion could be a viable continuous pretreatment method to be explored. The objectives of the current study were to investigate the influence of screw speed and barrel temperature on sugar recovery from the selected warm season grasses and to select a suitable enzyme combination and dose for enzymatic hydrolysis. The ground, moisture-balanced biomasses were pretreated using a single screw extruder at various screw speeds (100, 150, and 200 rpm) and barrel temperatures (50, 75, 100, 150, and 200°C). Cellulase or multienzyme with β-glucosidase was varied from 1 : 1 to 1 : 4 during enzymatic hydrolysis to accomplish the second objective. Screw speed, barrel temperature, and their interaction had a significant influence on sugar recovery from the selected biomasses. A maximum of 28.2, 66.2, and 49.2% of combined sugar recoverywasachieved for switchgrass, big bluestem, prairie cord grass when pretreated at a screw speed of 200, 200, and 150 rpm and at a barrel temperature of 75, 150, and 100°C, respectively, using cellulase and β-glucosidase at a ratio of 1 :  4. Extrusion pretreatment of these biomasses used only 28-37% of the rated extruder power.

No MeSH data available.


Related in: MedlinePlus

Effect of screw speed and barrel temperature on sugar recovery from big bluestem ((a, d)—1 : 1 cellulase and β-glucosidase, (b, e)—1 : 4 cellulase and β-glucosidase, and (c, f)—1 : 1 multienzyme and β-glucosidase).
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fig2: Effect of screw speed and barrel temperature on sugar recovery from big bluestem ((a, d)—1 : 1 cellulase and β-glucosidase, (b, e)—1 : 4 cellulase and β-glucosidase, and (c, f)—1 : 1 multienzyme and β-glucosidase).

Mentions: As observed from Figure 2 the sugar recovery from big bluestem increased with an increase in screw speed across the enzyme combinations and ratios. The screw speed showed a significant difference on sugar recovery when 1 : 1 cellulase and β-glucosidase was used (Figure 2(a)). As the screw speed was increased from 100 to 200 rpm, the glucose, xylose, and combined sugar recovery also increased by 28.3, 57.4, and 32.2%, respectively. A similar result was reported by Muthukumarappan and Julson [14] for big bluestem pretreated using a twin screw extruder while varying the screw speed from 200 to 400 rpm. However, the sugar recovery obtained by these authors is less than that of the present study. The difference might be due to type of extruder and pretreatment conditions, apart from chemical composition of big bluestem. Higher sugar recovery was recorded when β-glucosidase amount was increased by four times while cellulase amount was maintained at same level. However, the increase in sugar recovery was not statistically different across the screw speeds as noticed in Figure 2(b). When multienzyme with β-glucosidase was used at a ratio of 1 : 1, the sugar recovery from big bluestem increased irrespective of the screw speeds. The increase in glucose and combined sugar recovery was negligible when 1 : 1 multienzyme with β-glucosidase was employed during hydrolysis (Figure 2(c)) whereas, 1 : 1 cellulase and β-glucosidase showed significant increase on sugar recovery. A significant improvement on xylose recovery was observed as the screw speed was increased from 150 to 200 rpm (Figure 2(c)). Multienzyme with β-glucosidase (1 : 1) resulted in a lower sugar recovery among the enzyme combinations and ratios studied, and it was almost less than 50% of cellulase with β-glucosidase (1 : 1). These results showed that higher screw speed is required to disturb the cell wall structure of the big bluestem.


Effect of extruder screw speed, temperature, and enzyme levels on sugar recovery from different biomasses.

Karunanithy C, Muthukumarappan K, Gibbons WR - ISRN Biotechnol (2012)

Effect of screw speed and barrel temperature on sugar recovery from big bluestem ((a, d)—1 : 1 cellulase and β-glucosidase, (b, e)—1 : 4 cellulase and β-glucosidase, and (c, f)—1 : 1 multienzyme and β-glucosidase).
© Copyright Policy - open-access
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC4403594&req=5

fig2: Effect of screw speed and barrel temperature on sugar recovery from big bluestem ((a, d)—1 : 1 cellulase and β-glucosidase, (b, e)—1 : 4 cellulase and β-glucosidase, and (c, f)—1 : 1 multienzyme and β-glucosidase).
Mentions: As observed from Figure 2 the sugar recovery from big bluestem increased with an increase in screw speed across the enzyme combinations and ratios. The screw speed showed a significant difference on sugar recovery when 1 : 1 cellulase and β-glucosidase was used (Figure 2(a)). As the screw speed was increased from 100 to 200 rpm, the glucose, xylose, and combined sugar recovery also increased by 28.3, 57.4, and 32.2%, respectively. A similar result was reported by Muthukumarappan and Julson [14] for big bluestem pretreated using a twin screw extruder while varying the screw speed from 200 to 400 rpm. However, the sugar recovery obtained by these authors is less than that of the present study. The difference might be due to type of extruder and pretreatment conditions, apart from chemical composition of big bluestem. Higher sugar recovery was recorded when β-glucosidase amount was increased by four times while cellulase amount was maintained at same level. However, the increase in sugar recovery was not statistically different across the screw speeds as noticed in Figure 2(b). When multienzyme with β-glucosidase was used at a ratio of 1 : 1, the sugar recovery from big bluestem increased irrespective of the screw speeds. The increase in glucose and combined sugar recovery was negligible when 1 : 1 multienzyme with β-glucosidase was employed during hydrolysis (Figure 2(c)) whereas, 1 : 1 cellulase and β-glucosidase showed significant increase on sugar recovery. A significant improvement on xylose recovery was observed as the screw speed was increased from 150 to 200 rpm (Figure 2(c)). Multienzyme with β-glucosidase (1 : 1) resulted in a lower sugar recovery among the enzyme combinations and ratios studied, and it was almost less than 50% of cellulase with β-glucosidase (1 : 1). These results showed that higher screw speed is required to disturb the cell wall structure of the big bluestem.

Bottom Line: Biofuels from biomass have the potential to reduce the dependency on fossil fuels.Screw speed, barrel temperature, and their interaction had a significant influence on sugar recovery from the selected biomasses.Extrusion pretreatment of these biomasses used only 28-37% of the rated extruder power.

View Article: PubMed Central - PubMed

Affiliation: Department of Agricultural Biosystems Engineering, South Dakota State University, 1400 North Campus Drive, Brookings, SD 57007, USA.

ABSTRACT
Biofuels from biomass have the potential to reduce the dependency on fossil fuels. An efficient pretreatment method is required to accomplish the target of the Energy Act 2005. Extrusion could be a viable continuous pretreatment method to be explored. The objectives of the current study were to investigate the influence of screw speed and barrel temperature on sugar recovery from the selected warm season grasses and to select a suitable enzyme combination and dose for enzymatic hydrolysis. The ground, moisture-balanced biomasses were pretreated using a single screw extruder at various screw speeds (100, 150, and 200 rpm) and barrel temperatures (50, 75, 100, 150, and 200°C). Cellulase or multienzyme with β-glucosidase was varied from 1 : 1 to 1 : 4 during enzymatic hydrolysis to accomplish the second objective. Screw speed, barrel temperature, and their interaction had a significant influence on sugar recovery from the selected biomasses. A maximum of 28.2, 66.2, and 49.2% of combined sugar recoverywasachieved for switchgrass, big bluestem, prairie cord grass when pretreated at a screw speed of 200, 200, and 150 rpm and at a barrel temperature of 75, 150, and 100°C, respectively, using cellulase and β-glucosidase at a ratio of 1 :  4. Extrusion pretreatment of these biomasses used only 28-37% of the rated extruder power.

No MeSH data available.


Related in: MedlinePlus