Bioethanol production from rice straw residues (original) (raw)
Related papers
Journal of Food Science and Engineering, 2015
Effect of commercial cellulose enzymes was investigated by batch enzymatic hydrolysis at 15.0% (w/v) solid. It was found that the best commercial cellulose enzyme was Cellic ® CTec comparing to Accellerase 1000 TM and Accelerase 1500 TM. The Cellic ® CTec gave the highest reducing sugar concentration and rice straw conversion. Moreover, when the hydrolysate obtained from hydrolysis using Cellic ® CTec was fermented by Saccharomyces cerevisiae TISTR 5596, it would give the highest ethanol. In this study, the Cellic ® CTec was used for fed-batch prehydrolysis prior to ethanol production by simultaneous saccharification and fermentation (SSF) way at 20% (w/v) solid loading. It could produce 35.76 g/L or 4.6% (v/v) of ethanol concentration and 83.67 L/ton dry matter (DM) of yield.
Sequential cellulase production, saccharification and ethanol fermentation using rice straw
2012
This study presents alkali pretreated rice straw for cellulase production using Aspergillus niger CP1 by solid state fermentation (SSF). On 8th day, 140±2.4 IU g/l dry substrate (ds) carboxy methyl cellulose CMCase), 15±1.2 IU g/l ds filter paper activity (FPA) and 24±1.1 IU g/l ds â-glucosidase activities were noted. On extraction of 120 g material with 1 l of 0.1 mol/l citrate buffer, 5.9±0.12 IU ml/l CMCase, 0.62±0.001 IU ml/l FPA and 1.11±0.002 IU/ml â-glucosidase were obtained. When extracted enzyme was used for saccharification of 120 g fresh pretreated rice straw containing 100 g holocellulose, 45±0.2 g, sugars (50 g/l) were released in 900 ml hydrolysate to give 45% hydrolysis. Hydrolysate after yeast fermentation gave 15.6±0.05 g/l ethanol with a yield of 0.4±0.011 g/l/h and 78% fermentation efficiency. In sequential enzyme production, saccharification and fermentation studies, on 8th day of cellulase production by SSF, temperature was shifted from 28±1°C to 55°C for 36 h, ...
THE 2ND INTERNATIONAL SYMPOSIUM OF INDONESIAN CHEMICAL ENGINEERING 2021: Enhancing Innovations and Applications of Chemical Engineering for Accelerating Sustainable Development Goals
Bioethanol produced through hydrolysis and fermentation processes has great potential for usage as a liquid biofuel to be combined with fossil fuels. Its use and presence as an energy source does not interfere with the availability of food sources, and it has the potential as biomass to produce biofuel, in this case, bioethanol, because it contains 29.63 percent cellulose, 17.11 percent hemicellulose, and 12.17 percent lignin, all of which can be used to produce glucose via the hydrolysis process. Straw was utilized in this study for bioethanol synthesis via Separate Hydrolysis and Fermentation or SHF. In the fermentation process, Saccharomyces cereviceae is used as an organism. The goal of this study was to investigate the effect of the catalyst used in this case, cellulolytic enzymes, specifically cellulase enzymes and a combination of cellulase cellobiose enzymes in the hydrolysis process that affects glucose production on the levels of bioethanol produced, cellulose and cellobiose enzymes are used because rice straw contains the highest concentration of lignocellulose. The results of the experiments revealed that the cellulase enzyme achieved the highest output of reducing sugar (12.70 g/L) at a concentration of 5% and an incubation duration of 72 hours, yielding 5.9% bioethanol. The cellulase cellobiose enzyme combination produced reducing sugar yield (15.21 g/L) at a ratio of 2:1 and incubation time of 72 hours and produced the highest bioethanol yield of up to 27.40 percent. Rice straw is a potential raw material for bioethanol production employing a mixture of cellulase cellobiose enzyme catalysts and can be used as a new and renewable energy source..
3 Biotech, 2011
Cellulose is a major constituent of renewable lignocellulosic waste available in large quantities and is considered the most important reservoir of carbon for the production of glucose, for alternative fuel and as a chemical feedstock. Over the past decade, the emphasis has been on the enzymatic hydrolysis of cellulose to glucose and the efficiency of which depends on source of cellulosic substrate, its composition, structure, pretreatment process, and reactor design. In the present study, efforts were made to produce cellulase enzyme using rice straw. The produced enzyme was used for the hydrolysis of selected lignocellulosic substrate, i.e., sorghum straw. When rice straw was used as a substrate for cellulase production under solid state fermentation, the highest enzyme activity obtained was 30.7 FPU/gds, using T. reesei NCIM 992. 25 FPU/g of cellulase was added to differently treated (native, alkali treated, alkali treated followed by 3% acid treated and alkali treated followed by 3 and 5% acid treated) sorghum straw and hydrolysis was carried out at 50°C for 60 h. 42.5% hydrolysis was obtained after 36 h of incubation. Optimization of enzyme loading, substrate concentration, temperature, time and buffer yielded a maximum of 546.00 ± 0.55 mg/g sugars (54.60 ± 0.44 g/l) with an improved hydrolysis efficiency of 70 ± 0.45%. The enzymatic hydrolyzate can be used for fermentation of ethanol by yeasts.
Production of Cellulase for Ethanol Fermentation from Pretreated Wheat Straw
Iranian Journal of Science and Technology, Transactions A: Science, 2016
Effect of different media compositions on cellulase production was observed using a strain of Trichoderma viride. Medium with yeast extract as nitrogen source was found the best from the other sources used. Then two modes of fermentation solid state and submerged were compared for the enhanced cellulase production. Better cellulase activity was observed in submerged fermentation than the solid state fermentation. Effect of mash size and agitation was also studied. Small mash size with agitation showed higher cellulase activity than the large size pretreated wheat straw. Bacillus cellulosilyticus was also used for the cellulase production. Trichoderma produced enhanced activities of cellulase enzyme (20.738 ± 0.006 IU). Scarification of pretreated wheat straw released maximum sugar up to 16.1 g/L, after hydrolysis in 48 h using indigenously produced enzyme. The optimum conditions for the saccharification of pretreated wheat straw were 5 and 30°C for pH and temperature, respectively in 48 h. The yield of ethanol was observed 10.4 g/L in saccharified wheat straw based medium.
AFRICAN JOURNAL OF BIOTECHNOLOGY
Enzymatic hydrolysis of the cellulose fraction of rice straw to glucose using solid-state fermentation for bioethanol production is a focus of current attention. A total of 10 actinomycetes isolates were isolated from soils and decayed rice straw. All these isolates were purified and screened for their cellulolytic activity; one strain was selected for further study and identified as Streptomyces viridiochromogenes. Optimization of fermentation conditions showed highest cellulolytic enzymes production on the 5th day at pH 6.5 and at 40°C. The production of enzymes reached its maximal value at 4.0 g of rice straw/250 ml flask. Avicelase and total cellulase productivity were highly increased by the addition of NH 4 Cl as Nsource, while maximum activity of CMCase was recorded by the addition of peptone as N-source to the fermentation medium. The influence of various physico-chemical factors on enzyme activity was also investigated. The half life time of avicelase, total cellulase and CMCase at 60°C was 39.4, 50.0 and 78.58 min, respectively. A maximum of ethanol production 1.428±0.074% (v/v) by Saccharomyces cereviseae using dilute acid pretreated rice straw hydrolysate with initial soluble sugar 2.340±0.072% was recorded after 2 days of fermentation.
Cellulosic ethanol production from green solvent-pretreated rice straw
Biocatalysis and Agricultural Biotechnology, 2016
Cellulosic ethanol production from green solvent (GS)-pretreated rice straw and the effects of green solvents on cellulase enzyme cellic ctec2 and cellobiose-fermenting yeast strain Clavispora NRRL Y-50464 was comprehensively investigated. Using choline chloride/glycerol (CC-GLY) treated rice straw, maximum reducing sugars of 226.7 g/L was obtained with a saccharification efficiency of 87.1% at 20% solids loading and 12 FPU cellic ctec2. An ethanol production of 36.7 g/L was observed from 8% of glucose within 36 h with a conversion efficiency of 90.1%. Incubation of cellulase in green solvents (CC-GLY, choline chloride/1,2-propane diol (CC-PD), choline chloride/ethylene glycol (CC-EG)) at high concentrations (up to 30%, v/v) had no inhibitory effect on cellic ctec2. Moreover, CC-GLY and CC-PD at 10% (v/v) did not affect the growth rate, sugar consumption and ethanol production from Clavispora NRRL Y-50464, while 10% (v/v) CC-EG repressed and delayed the cell growth of the microbe. While, strain Y-50464 was highly sensitive in other green reagents that were evaluated in this study. The green solvent-pretreatment efficiently removed lignin from the ricestraw and improved fermentation efficiency significantly. Green solvents with pH o 3.0 inhibited of cellic ctec2 enzyme activity and growth of Clavispora strain NRRL Y-50464. When pH of the green reagents was neutralized or adjusted to pH 5.0, normal enzyme activity and cell growth was observed. Moreover, with selective green reagents i.e. CC-GLY, CC-PD, and CC-EG, cellulosic ethanol production can be accomplished using cellic ctec2 and strain NRRL Y-50464.