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1.
Gong-Yuan Wei You-Jung Lee Yi-Joon Kim Il-Hyuck Jin Jai-Heon Lee Chung-Han Chung Jin-Woo Lee 《Applied biochemistry and biotechnology》2010,162(5):1471-1482
The production of fermentable sugars from rice hull was studied by dilute acid pretreatment and enzymatic saccharification.
Rice hull (15%, w/v) was pretreated by 1% (v/v) sulfuric acid at high temperature (120∼160 °C) for 15, 30, 45, and 60 min, respectively. The maximum sugar concentration
from rice hull in the prehydrolysate was obtained at 140 °C for 30 min, but the enzymatic saccharification yield from the
corresponding pretreated rice hull is not high. To another aspect, the maximum enzymatic saccharification yield was achieved
at 160 °C for 60 min, while the recovery of fermentable sugars was the poorest. To take account of fermentable sugars from
pretreatment and enzymatic saccharification, the maximum yield of sugars was obtained only when rice hull was treated at 140 °C
for 30 min. Under this condition, 72.5% (w/w) of all sugars generated from the raw material can be recovered. The kinetic study on the enzymatic saccharification of dilute
acid pretreated rice hull was also performed in this work by a modified Michaelis–Menten model and a diffusion-limited model.
After calculation by a linear and a non-linear regression analysis, both models showed good relation with the experimental
results. 相似文献
2.
Hossein Noureddini Jongwon Byun Ta-Jen Yu 《Applied biochemistry and biotechnology》2009,159(2):553-567
Distillers’ grains and corn fiber are the coproducts of the corn dry grind and wet milling industries, respectively. Availability
of distillers’ grains and corn fiber at the ethanol plant and their high levels of lignocellulosic material make these coproducts
attractive feedstocks for conversion to ethanol. In this study, dilute sulfuric acid hydrolysis of these coproducts was investigated
in a multistage scheme. After the completion of each pretreatment stage, the liquid substrate was separated and reused in
the succeeding pretreatment stage with a fresh substrate. The substrate from each stage was also subjected to enzyme hydrolysis
in a separate experiment. The sulfuric acid concentration and the substrate loading were maintained at 1.0 vol% and 15.0 wt.%,
respectively, and the temperature was maintained at 120 °C in all the experiments. Experiments were also performed to study
the effect of removing oil from the samples prior to the pretreatment. The highest concentration of monomeric sugars (MS)
was observed when three stages of pretreatment were followed by the enzyme reaction. The enzyme hydrolysis of the three-stage
pretreated dried distillers’ grains and corn fiber yielded 122.6 ± 5.8 and 184.5 ± 4.1 mg/mL of MS, respectively. The formation
of inhibitory products was also monitored. 相似文献
3.
Youngran Kim Anna Yu Minhee Han Gi-wook Choi Bongwoo Chung 《Applied biochemistry and biotechnology》2011,163(1):143-152
The fermentable sugars in lignocellulosic biomass are derived from cellulose and hemicellulose, which are not readily accessible
to enzymatic saccharification because of their recalcitrance. An ethanosolv pretreatment method was applied for the enzymatic
saccharification of barley straw with an inorganic acid. The effects of four process variables (temperature, time, catalyst
dose, and ethanol concentration) on the barley straw pretreatment were analyzed over a broad range using a small composite
design and a response surface methodology. The yield of the residual solid and composition of the solid fraction differed
as ethanosolv conditions varied within the experimental range. A glucan recovery, xylan recovery, and delignification were
85%, 14%, and 69% at center point conditions (170°C, 60 min, 1.0% (w/w) H2SO4, and 50% (w/w) ethanol), respectively. Ethanosolv pretreatment removed lignin effectively. Additionally, the highest enzymatic digestibility
of 85.3% was obtained after 72 h at center point conditions. 相似文献
4.
Shona Duncan Qing Jing Adrian Katona Romas J. Kazlauskas Jonathan Schilling Ulrike Tschirner Waleed Wafa AlDajani 《Applied biochemistry and biotechnology》2010,160(6):1637-1652
The recalcitrance of lignocellulosic biomass to enzymatic release of sugars (saccharification) currently limits its use as
feedstock for biofuels. Enzymatic hydrolysis of untreated aspen wood releases only 21.8% of the available sugars due primarily
to the lignin barrier. Nature uses oxidative enzymes to selectively degrade lignin in lignocellulosic biomass, but thus far,
natural enzymes have been too slow for industrial use. In this study, oxidative pretreatment with commercial peracetic acid
(470 mM) removed 40% of the lignin (from 19.9 to 12.0 wt.% lignin) from aspen and enhanced the sugar yields in subsequent
enzymatic hydrolysis to about 90%. Increasing the amount of lignin removed correlated with increasing yields of sugar release.
Unfortunately, peracetic acid is expensive, and concentrated forms can be hazardous. To reduce costs and hazards associated
with using commercial peracetic acid, we used a hydrolase to catalyze the perhydrolysis of ethyl acetate generating 60–70 mM
peracetic acid in situ as a pretreatment to remove lignin from aspen wood. A single pretreatment was insufficient, but multiple
cycles (up to eight) removed up to 61.7% of the lignin enabling release of >90% of the sugars during saccharification. This
value corresponds to a predicted 581 g of fermentable sugars from 1 kg of aspen wood. Improvements in the enzyme stability
are needed before the enzymatically generated peracetic acid is a commercially viable alternative. 相似文献
5.
R. Torget M. Himmel J. D. Wright K. Grohmann 《Applied biochemistry and biotechnology》1988,17(1-3):89-104
A preliminary process design for dilute sulfuric acid pretreatment of aspen wood chips in order to obtain fermentable sugars
has been prepared and subjected to an economic evaluation. The process design was prepared according to experimental data
on the kinetics of dilute sulfuric acid prehydrolysis and particle size effects obtained in this study and our previous work.
The initial economic evaluation shows woodchips are 56% of the cost of production, whereas the reactor is only 4%, and the
comminution operation is just under 10%, indicating that the process economics are extremely vulnerable to feedstock costs
and are thus yield-sensitive. Although chances for major cost improvements by modification of the reactor design and finding
alternatives to dry milling of aspen chips to small (20–80 mesh) particles needed for acid penetration and enzymatic saccharification
are not great, design improvements of the process will necessitate development of a cheaper acid resistant pretreatment reactor
and a less energy intensive comminution system. Experimental results on effects of particle size on the dilute acid pretreatment
design are presented. 相似文献
6.
Pretreatment and enzymatic saccharification of corn fiber 总被引:14,自引:0,他引:14
Corn fiber consists of about 20% starch, 14% cellulose, and 35% hemicellulose, and has the potential to serve as a low-cost
feedstock for production of fuel ethanol. Several pretreatments (hot water, alkali, and dilute, acid) and enzymatic saccharification
procedures were evaluated for the conversion of corn fiber starch, cellulose, and hemicellulose to monomeric sugars. Hot water
pretreatment (121°C, 1 h) facilitated the enzymatic sacch arification of starch and cellulose but not hemicellulose. Hydrolysis
of corn fiber pretreated with alkali un dersimilar conditions by enzymatic means gave similar results. Hemicellulose and starch
components were converted to monomeric sugars by dilute H2SO4 pretreatment (0.5–1.0%, v/v) at 121°C. Based on these findings, a method for pretreatment and enzymatic saccharification
of corn fiber is presented. It in volves the pretreatment of corn fiber (15% solid, w/v) with dilute acid (0.5% H2SO4, v/v) at 121°C for 1 h, neutralization to pH 5.0, then saccharification of the pretreated corn fiber material with commercial
cellulase and β-glucosidase preparations The yield of monomeric sugars from corn fiber was typically 85–100% of the theoretical
yield.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
7.
Barley is an abundant crop in Europe, which makes its straw residues an interesting cellulose source for ethanol production.
Steam pretreatment of the straw followed by enzymatic hydrolysis converts the cellulose to fermentable sugars. Prior to pretreatment
the material is impregnated with a catalyst, for example, H2SO4, to enhance enzymatic digestibility of the pretreated straw. Different impregnation techniques can be applied. In this study,
soaking and spraying were investigated and compared at the same pretreatment condition in terms of overall yield of glucose
and xylose. The overall yield includes the soluble sugars in the liquid from pretreatment, including soluble oligomers, and
monomer sugars obtained in the enzymatic hydrolysis. The yields obtained differed for the impregnation techniques. Acid-soaked
barley straw gave the highest overall yield of glucose, regardless of impregnation time (10 or 30 min) or acid concentration
(0.2 or 1.0 wt%). For xylose, soaking gave the highest overall yield at 0.2 wt% H2SO4. An increase in acid concentration resulted in a decrease in xylose yield for both acid-soaked and acid-sprayed barley straw.
Optimization of the pretreatment conditions for acid-sprayed barley straw was performed to obtain yields using spraying that
were as high as those with soaking. For acid-sprayed barley straw the optimum pretreatment condition for glucose, 1.0 wt%
H2SO4 and 220°C for 5 min, gave an overall glucose yield of 92% of theoretical based on the composition of the raw material. Pretreatment
with 0.2wt% H2SO4 at 190°C for 5 min resulted in the highest overall xylose yield, 67% of theoretical based on the composition of the raw material. 相似文献
8.
Saha Badal C. Dien Bruce S. Bothast Rodney J. 《Applied biochemistry and biotechnology》1998,(1):115-125
Corn fiber, which consists of about 20% starch, 14% cellulose, and 35% hemicellulose, has the potential to serve as a low
cost feedstock for production of fuel ethanol. Currently, the use of corn fiber to produce fuel ethanol faces significant
technical and economic challenges. Its success depends largely on the development of environmentally friendly pretreatment
procedures, highly effective enzyme systems for conversion of pretreated corn fiber to fermentable sugars, and efficient microorganisms
to convert multiple sugars to ethanol. Several promising pretreatment and enzymatic processes for conversion of corn fiber
cellulose, hemicellulose, and remaining starch to fermentable sugars were evaluated. These hydrolyzates were then examined
for ethanol production in bioreactors, using genetically modified bacteria and yeast. Several novel enzymes were also developed
for use in pretreated corn fiber saccharification.
Names are necessary to report factually on available data; however, the USDA neither guarantees nor warrants the standard
of the product, and the use of the name by USDA implies no approval of the product to the exclusion of others that may also
be suitable. 相似文献
9.
《印度化学会志》2021,98(12):100264
After harvesting season, large amounts of durian peels were produced and uselessly disposed of by combustion or landfilling leading to environmental pollution and human health hazards. Proper management of these wastes is necessary to reduce not only an environmental problem but also to create value-added products. Herein, we optimized sulfuric acid pretreatment to promote enzymatic saccharification of durian peels and convert fermentable sugars to bioethanol. Three pretreatment parameters were optimized based on Response Surface Methodology (RSM), including acid concentration (0.5%–3.5%), temperature (60–140 °C), and time (20–100 min). At optimal pretreatment condition using 2.75% H2SO4, at 127.14 °C for 74.13 min, 0.53 g/g-biomass of reducing sugars were produced, which is 1.88 folds higher than the untreated durian peel. The pretreatment liquor and biomass hydrolysate were analyzed by Gas Chromatograph-Mass spectrometer (GC-MS), and fermentation inhibitors, i.e. acetic acid, furfural, and furan methanol, were identified in those fractions. Due to pretreatment at the optimal condition, a higher yield of reducing sugar was observed, and the production of ethanol from the pretreated biomass was 5.70 g/L (equivalent to 87.43% of theoretical yields). These findings demonstrated the potential of using durian waste in the biorefinery concept to achieve a concept of the green economy. 相似文献
10.
Silva NL Betancur GJ Vasquez MP Gomes Ede B Pereira N 《Applied biochemistry and biotechnology》2011,163(7):928-936
Current research indicates the ethanol fuel production from lignocellulosic materials, such as residual wood chips from the
cellulose industry, as new emerging technology. This work aimed at evaluating the ethanol production from hemicellulose of
eucalyptus chips by diluted acid pretreatment and the subsequent fermentation of the generated hydrolysate by a flocculating
strain of Pichia stipitis. The remaining solid fraction generated after pretreatment was subjected to enzymatic hydrolysis, which was carried out simultaneously
with glucose fermentation [saccharification and fermentation (SSF) process] using a strain of Saccharomyces cerevisiae. The acid pretreatment was evaluated using a central composite design for sulfuric acid concentration (1.0–4.0 v/v) and solid to liquid ratio (1:2–1:4, grams to milliliter) as independent variables. A maximum xylose concentration of 50 g/L
was obtained in the hemicellulosic hydrolysate. The fermentation of hemicellulosic hydrolysate and the SSF process were performed
in bioreactors and the final ethanol concentrations of 15.3 g/L and 28.7 g/L were obtained, respectively. 相似文献
11.
Beatriz Palmarola-Adrados Mats Galbe Guido Zacchi 《Applied biochemistry and biotechnology》2004,115(1-3):989-1002
Steam treatment of an industrial process stream, denoted starch-free wheat fiber, was investigated to improve the formation
of monomeric sugars in subsequent enzymatic hydrolysis for further bioconversion into ethanol. The solid fraction in the process
stream, derived from a combined starch and ethanol factory, was rich in arabinose (21.1%), xylose (30.1%), and glucose (18.6%),
in the form of polysaccharides. Various conditions of steam pretreatment (170–220°C for 5–30 min) were evaluated, and their
effect was assessed by enzymatic hydrolysis with 2 g of Celluclast + Ultraflo mixture/ 100 g of starch-free fiber (SFF) slurry
at 5% dry matter (DM). The highest overall sugar yield for the combined steam pretreatment and enzymatic hydrolysis, 52g/100
g of DM of SFF, corresponding to 74% of the theoretical, was achieved with pretreatment at 190°C for 10 min followed by enzymatic
hydrolysis. 相似文献
12.
Tengborg Charlotte Stenberg Kerstin Galbe Mats Zacchi Guido Larsson Simona Palmqvist Eva Hahn-Hägerdal Bärbel 《Applied biochemistry and biotechnology》1998,(1):3-15
The pretreatment of softwood with sulfuric acid impregnation in the production of ethanol, based on enzymatic hydrolysis,
has been investigated. The parameters investigated were: H2SO4 concentration (0.5 – 4.4% w/w liquid), temperature (180 – 240°C), and residence time (1-20 minutes). The combined severity
(log Ro-pH) was used to combine the parameters into a single reaction ordinate. The highest yields of fermentable sugars,
i.e., glucose and mannose, were obtained at a combined severity of 3. At this severity, however, the fermentability declined
and the ethanol yield decreased. In a comparison with previous results, SO2 impregnation was found to be preferable, since it resulted in approximately the same sugar yields, but better fermentability. 相似文献
13.
Summary of findings from the Biomass Refining Consortium for Applied Fundamentals and Innovation (CAFI): corn stover pretreatment 总被引:1,自引:0,他引:1
Richard T. Elander Bruce E. Dale Mark Holtzapple Michael R. Ladisch Y. Y. Lee Colin Mitchinson John N. Saddler Charles E. Wyman 《Cellulose (London, England)》2009,16(4):649-659
The Biomass Refining Consortium for Applied Fundamentals and Innovation, with members from Auburn University, Dartmouth College,
Michigan State University, the National Renewable Energy Laboratory, Purdue University, Texas A&M University, the University
of British Columbia, and the University of California at Riverside, has developed comparative data on the conversion of corn
stover to sugars by several leading pretreatment technologies. These technologies include ammonia fiber expansion pretreatment,
ammonia recycle percolation pretreatment, dilute sulfuric acid pretreatment, flowthrough pretreatment (hot water or dilute
acid), lime pretreatment, controlled pH hot water pretreatment, and sulfur dioxide steam explosion pretreatment. Over the
course of two separate USDA- and DOE-funded projects, these pretreatment technologies were applied to two different corn stover
batches, followed by enzymatic hydrolysis of the remaining solids from each pretreatment technology using identical enzyme
preparations, enzyme loadings, and enzymatic hydrolysis assays. Identical analytical methods and a consistent material balance
methodology were employed to develop comparative sugar yield data for each pretreatment and subsequent enzymatic hydrolysis.
Although there were differences in the profiles of sugar release, with the more acidic pretreatments releasing more xylose
directly in the pretreatment step than the alkaline pretreatments, the overall glucose and xylose yields (monomers + oligomers)
from combined pretreatment and enzymatic hydrolysis process steps were very similar for all of these leading pretreatment
technologies. Some of the water-only and alkaline pretreatment technologies resulted in significant amounts of residual xylose
oligomers still remaining after enzymatic hydrolysis that may require specialized enzyme preparations to fully convert xylose
oligomers to monomers. 相似文献
14.
Chang Geun Yoo Nhuan P. Nghiem Kevin B. Hicks Tae Hyun Kim 《Applied biochemistry and biotechnology》2013,169(8):2430-2441
Soaking in aqueous ammonia (SAA) pretreatment was investigated to improve enzymatic digestibility and consequently to increase total fermentable sugar production from barley straw. Various effects of pretreatment process parameters, such as reaction temperature, reaction time, solid:liquid ratio, and ammonia concentration, were evaluated, and the optimum conditions for two of the most important factors, reaction temperature and time were determined using response surface methodology. Optimized reaction conditions were 77.6 °C treatment temperature, 12.1 h. treatment time, 15 wt.% ammonia concentration, and 1:8 solid-to-liquid ratio, which gave a sugar recovery yield of 71.5 % (percent of theoretical sugar recovered from the untreated barley straw) with enzyme loading of 15 FPU/g-glucan. In the optimization of the SAA pretreatment process, ammonia concentration, reaction temperature, and reaction time were determined to be the most significant factors correlated to subsequent enzyme digestibility. Based on tested conditions exhibiting high sugar recovery yields of >60 %, it appeared that reaction temperature affected total fermentable sugar production more significantly than reaction time. 相似文献
15.
Optimization of steam pretreatment of corn stover to enhance enzymatic digestibility 总被引:5,自引:0,他引:5
Among the available agricultural byproducts, corn stover, with its yearly production of 10 million t (dry basis), is the most
abundant promising raw material for fuel ethanol production in Hungary. In the United States, more than 216 million to fcorn
stover is produced annually, of which a portion also could possibly be collected for conversion to ethanol. However, a network
of lignin and hemicellulose protects cellulose, which is the major source of fermentable sugars in corn stover (approx 40%
of the dry matter [DM]). Steam pretreatment removes the major part of the hemicellulose from the solid material and makes
the cellulose more susceptible to enzymatic digestion. We studied 12 different combinations of reaction temperature, time,
and pH during steam pretreatment. The best conditions (200°C, 5 min, 2% H2SO4) increased the enzymatic conversion (from cellulose to glucose) of corn stover more then four times, compared to untreated
material. However, steam pretreatment at 190°C for 5 min with 2% sulfuric acid resulted in the highest overall yield of sugars,
56.1 g from 100 g of untreated material (DM), corresponding to 73% of the theoretical. The liquor following steam explosion
was fermented using Saccharomyces cerevisiae to investigate the inhibitory effect of the pretreatment. The achieved ethanol yield was slightly higher than that obtained
with a reference sugar solution. This demonstrates that baker's yeast could adapt to the pretreated liquor and ferment the
glucose to ethanol efficiently. 相似文献
16.
Evaluation and Characterization of Forage Sorghum as Feedstock for Fermentable Sugar Production 总被引:2,自引:0,他引:2
Corredor DY Salazar JM Hohn KL Bean S Bean B Wang D 《Applied biochemistry and biotechnology》2009,158(1):164-179
Sorghum is a tropical grass grown primarily in semiarid and drier parts of the world, especially areas too dry for corn. Sorghum
production also leaves about 58 million tons of by-products composed mainly of cellulose, hemicellulose, and lignin. The low
lignin content of some forage sorghums such as brown midrib makes them more digestible for ethanol production. Successful
use of biomass for biofuel production depends on not only pretreatment methods and efficient processing conditions but also
physical and chemical properties of the biomass. In this study, four varieties of forage sorghum (stems and leaves) were characterized
and evaluated as feedstock for fermentable sugar production. Fourier transform infrared spectroscopy and X-ray diffraction
were used to determine changes in structure and chemical composition of forage sorghum before and after pretreatment and the
enzymatic hydrolysis process. Forage sorghums with a low syringyl/guaiacyl ratio in their lignin structure were easy to hydrolyze
after pretreatment despite the initial lignin content. Enzymatic hydrolysis was also more effective for forage sorghums with
a low crystallinity index and easily transformed crystalline cellulose to amorphous cellulose, despite initial cellulose content.
Up to 72% hexose yield and 94% pentose yield were obtained using modified steam explosion with 2% sulfuric acid at 140 °C
for 30 min and enzymatic hydrolysis with cellulase (15 filter per unit (FPU)/g cellulose) and β-glucosidase (50 cellobiose
units (CBU)/g cellulose). 相似文献
17.
C.L. Duarte M.A. Ribeiro H. Oikawa M.N. Mori C.M. Napolitano C.A. Galvão 《Radiation Physics and Chemistry》2012,81(8):1008-1011
The use of microbial cellulolytic enzymes is the most efficient process to liberate glucose from cellulose in biomass without the formation of fermentation inhibitors. A combination of pretreatment technologies is an alternative way to increase the access of enzymes to cellulose, and consequently, the conversion yield. In this way, the present study reports on the enzymatic hydrolysis of SCB submitted to three kinds of pretreatment: electron beam processing (EBP), and EBP followed by hydrothermal (TH) and diluted acid (AH) treatment. SCB samples were irradiated using a radiation dynamics electron beam accelerator, and then submitted to thermal and acid (0.1% sulfuric acid) hydrolysis for 40 and 60 min at 180 °C. These samples were submitted to enzymatic hydrolysis (EH) using commercial preparations, including Celluclast 1.5 L and beta-glycosidase. The addition of diluted acid improved TH treatment allowing for a shorter application time. EBP with 50 kGy increased the enzymatic hydrolysis yield of cellulose by 20% after TH and 30% after AH. 相似文献
18.
Tucker M. P. Farmer J. D. Keller F. A. Schell D. J. Nguyan Q. A. 《Applied biochemistry and biotechnology》1998,(1):25-35
Single-stage cocurrent dilute acid pretreatments were carried out on yellow poplar (Liriodendron tulipifera) sawdust using an as-installed and short residence time modified pilot-scale Sunds hydrolyzer and a 4-L bench-scale NREL
digester (steam explosion reactor). Pretreatment conditions for the Sunds hydrolyzer, installed in the NREL process development
unit (PDU), which operates at 1 t/d (bone-dry t) feed rate, spanned the temperature range of 160 – 210°C, 0.1 – 1.0% (w/w)
sulfuric acid, and 4-10-min residence times. The batch pretreatments of yellow poplar sawdust in the bench-scale digester
were carried out at 210 and 230°C, 0.26% (w/w) sulfuric acid, and 1-, 3-, and 4-min residence times. The dilute acid prehydrolysis
solubilized more than 90% of the hemicellulose, and increased the enzymatic digestibility of the cellulose that remained in
the solids. Compositional analysis of the pretreated solids and liquors and mass balance data show that the two pretreatment
devices had similar pretreatment performance. 相似文献
19.
Bagasse is one of the waste crop materials highlighted as commercially viable for cellulosic bio-ethanol production via enzymatic
conversion to release fermentable sugars. Genetically modified sugarcane expressing cellobiohydrolases (CBH), endoglucanase
(EG), and β-glucosidases (BG) provide a more cost-effective route to cellulose breakdown compared to culturing these enzymes
in microbial tanks. Hence, process monitoring of the concentration profile of these key cellulases in incoming batches of
sugarcane is required for fiscal measures and bio-ethanol process control. The existing methods due to their non-specificity,
requirement of trained analysts, low sample throughput, and low amenability to automation are unsuitable for this purpose.
Therefore, this paper explores a membrane-based sample preparation method coupled to capillary zone electrophoresis (CZE)
to quantify these enzymes. The maximum enzyme extraction efficiency was obtained by using a polyethersulfone membrane with
molecular cut-off of 10 kDa. The use of 15 mM, pH 7.75, phosphate buffer resulted in CZE separation and quantification of
CBH, EG, and BG within 10 min. Migration time reproducibility was between 0.56% and 0.7% and hence, suitable for use with
automatic peak detection software. Therefore, the developed CZE method is suitable for at-line analysis of BG, CBH, and EG
in every batch of harvested sugarcane. 相似文献
20.
S. I. Njoku B. K. Ahring H. Uellendahl 《Applied biochemistry and biotechnology》2013,170(7):1574-1588
The pretreatment of lignocellulosic biomass is crucial for efficient subsequent enzymatic hydrolysis and ethanol fermentation. In this study, wet explosion (WEx) pretreatment was applied to cocksfoot grass and pretreatment conditions were tailored for maximizing the sugar yields using response surface methodology. The WEx process parameters studied were temperature (160–210 °C), retention time (5–20 min), and dilute sulfuric acid concentration (0.2–0.5 %). The pretreatment parameter set E, applying 210 °C for 5 min and 0.5 % dilute sulfuric acid, was found most suitable for achieving a high glucose release with low formation of by-products. Under these conditions, the cellulose and hemicellulose sugar recovery was 94 % and 70 %, respectively. The efficiency of the enzymatic hydrolysis of cellulose under these conditions was 91 %. On the other hand, the release of pentose sugars was higher when applying less severe pretreatment conditions C (160 °C, 5 min, 0.2 % dilute sulfuric acid). Therefore, the choice of the most suitable pretreatment conditions is depending on the main target product, i.e., hexose or pentose sugars. 相似文献