Effect of Subsequent Dilute Acid and Enzymatic Hydrolysis on Reducing Sugar Production from Sugarcane Bagasse and Spent Citronella Biomass

Abstract

This work was aimed at investigating the effect of process parameters on dilute acid pretreatment and enzymatic hydrolysis of spent citronella biomass (after citronella oil extraction) and sugarcane bagasse on total reducing sugar (TRS) yield. In acid pretreatment, the parameters studied were acid concentration, temperature, and time. At the optimized condition (0.1 M H2SO4, 120°C, and 120 min), maximum TRS obtained was 452.27 mg·g−1and 487.50 mg·g−1for bagasse and citronella, respectively. Enzymatic hydrolysis of the pretreated biomass usingTrichoderma reesei26291 showed maximum TRS yield of 226.99 mg·g−1for citronella and 282.85 mg·g−1for bagasse at 10 FPU, 50°C, and 48 hr. The maximum crystallinity index (CI) of bagasse and citronella after acid pretreatment obtained from X-ray diffraction analysis was 64.41% and 56.18%, respectively. Decreased CI after enzymatic hydrolysis process to 37.28% and 34.16% for bagasse and citronella, respectively, revealed effective conversion of crystalline cellulose to glucose. SEM analysis of the untreated and treated biomass revealed significant hydrolysis of holocellulose and disruption of lignin.

Effect of Dilute Acid and Alkaline Pretreatments on Enzymatic Saccharfication of Palm Tree Trunk Waste for Bioethanol Production

“…In our experiments, saccharification rates were significantly higher after 72 h than after 24 and 48 h. Similarly with previous study [39] pretreated rice straw with ionic liquid showed that saccharification times of 24 and 72 h produced glucose yields of 75.4% and 90.9%, re- According to previous researcher [23] total reducing sugar (TRS) yields from hydrolysis of sugarcane bagasse and spent citronella biomasses increased with acid concentrations and reaction times. The highest TRS yield from citronella and bagasse was achieved after 48 h at 50 °C with 10 FPU of cellulase.…”

“…Residues were removed from solutions using filter paper on a vacuum filtration unit and were washed with distilled water to obtain neutral pH. Pretreated substrates were washed with water to reduce inhibitory product concentrations [23]. Residues were then dried until a constant weight was achieved and were used for the subsequent processing steps.…”

“…Assuming that extracted hemicellulose, lignin, ash, and cellulose are the only components, cellulose contents (%w/w) were calculated as the difference [23].…”

“…Sputter gold coating was then performed to prevent charging. All specimens were examined using a SEM under vacuum conditions at an accelerating voltage of 5 kV [23].…”

Sugarcane Bagasse Pretreatment Methods for Ethanol Production

“…Several different acids used in pretreatments of SCB, including dilute sulfuric acid [29][30][31][32][33][34][35], dilute hydrochloric acid [36], dilute phosphoric acid [32,37], and dilute nitric acid [38], have been reported. High hydrolysis yields have been obtained when lignocellulosic biomass was pretreated with dilute sulfuric acid compared with hydrochloric, phosphoric, and nitric acid [22].…”