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1.
Cascade Enzymatic Hydrolysis Coupling with Ultra ne Grinding Pretreatment for Sugarcane Bagasse Sacchari cation
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Zheng-qiu Yuan Jin-xing Long Tie-jun Wang Yu-qin Li Qi Zhang Long-long Ma 《化学物理学报(中文版)》2015,28(3):355-360
The biorefinery process for sugarcane bagasse saccharification generally requires significant accessibility of cellulose. We reported a novel method of cascade cellulase enzymatic hydrolysis coupling with ultrafine grinding pretreatment for sugarcane bagasse saccharification. Three enzymatic hydrolysis modes including single cellulase enzymatic hydrolysis, mixed cellulase enzymatic hydrolysis, and cascade cellulase enzymatic hydrolysis were compared. The changes on the functional group and surface morphology of bagasse during cascade cellulase enzymatic hydrolysis were also examined by FT-IR and SEM respectively. The results showed that cascade enzymatic hydrolysis was the most efficient way to enhance the sugarcane bagasse sacchari cation. More than 65% of reducing sugar yield with 90.1% of glucose selectivity was achieved at 50 oC, pH=4.8 for 72 h (1200 r/min) with cellulase I of 7.5 FPU/g substrate and cellulase II of 5 FPU/g substrate. 相似文献
2.
Adam Elliston Samuel R. A. Collins Craig B. Faulds Ian N. Roberts Keith W. Waldron 《Applied biochemistry and biotechnology》2014,172(7):3621-3634
Waste copier paper is a potential substrate for the production of glucose relevant for manufacture of platform chemicals and intermediates, being composed of 51 % glucan. The yield and concentration of glucose arising from the enzymatic saccharification of solid ink-free copier paper as cellulosic substrate was studied using a range of commercial cellulase preparations. The results show that in all cellulase preparations examined, maximum hydrolysis was only achieved with the addition of beta-glucosidase, despite its presence in the enzyme mixtures. With the use of Accellerase® (cellulase), high substrate loading decreased conversion yield. However, this was overcome if the enzyme was added between 12.5 and 20 FPU g substrate?1. Furthermore, this reaction condition facilitated continual stirring and enabled sequential additions (up to 50 % w/v) of paper to be made to the hydrolysis reaction, degrading nearly all (99 %) of the cellulose fibres and increasing the final concentration of glucose whilst simultaneously making high substrate concentrations achievable. Under optimal conditions (50 °C, pH 5.0, 72 h), digestions facilitate the production of glucose to much improved concentrations of up to 1.33 mol l?1. 相似文献
3.
Rosgaard L Andric P Dam-Johansen K Pedersen S Meyer AS 《Applied biochemistry and biotechnology》2007,143(1):27-40
In this study, the applicability of a “fed-batch” strategy, that is, sequential loading of substrate or substrate plus enzymes
during enzymatic hydrolysis was evaluated for hydrolysis of steam-pretreated barley straw. The specific aims were to achieve
hydrolysis of high substrate levels, low viscosity during hydrolysis, and high glucose concentrations. An enzyme system comprising
Celluclast and Novozyme 188, a commercial cellulase product derived from Trichoderma reesei and a β-glucosidase derived from Aspergillus niger, respectively, was used for the enzymatic hydrolysis. The highest final glucose concentration, 78 g/l, after 72 h of reaction,
was obtained with an initial, full substrate loading of 15% dry matter weight/weight (w/w DM). Conversely, the glucose yields,
in grams per gram of DM, were highest at lower substrate concentrations, with the highest glucose yield being 0.53 g/g DM
for the reaction with a substrate loading of 5% w/w DM after 72 h. The reactions subjected to gradual loading of substrate
or substrate plus enzymes to increase the substrate levels from 5 to 15% w/w DM, consistently provided lower concentrations
of glucose after 72 h of reaction; however, the initial rates of conversion varied in the different reactions. Rapid cellulose
degradation was accompanied by rapid decreases in viscosity before addition of extra substrate, but when extra substrate or
substrate plus enzymes were added, the viscosities of the slurries increased and the hydrolytic efficiencies decreased temporarily. 相似文献
4.
Cellulase distribution between residual substrate and supernatant in the process of enzymatic hydrolysis of steam-exploded
wheat straw was investigated. Subsequently, a novel stepwise recovery strategy with three successive steps was adopted to
recover cellulase adsorbed to the residual substrate. The results showed that cellulase protein in the supernatant increased
as the hydrolysis time increased. When hydrolysis ended, the cellulase remaining on the residual substrate accounted for 33–42%
of the original added cellulase according to the different cellulase loading. To obtain the maximum cellulase recovery rate,
the residual substrate was dealt with in three successive steps: washed with sodium acetate buffer (step 1), shaken with sodium
acetate buffer (step 2), and then treated with 0.0015 mol/L, pH 10 Ca(OH)2 (step 3). The total cellulase protein recovered by the three steps reached 96.70–98.14%. The enzyme activity of cellulase
recovered by the first two steps was kept well. The ratios of the specific activity between the recovered cellulase and the
original were 89–96%, which was by far higher than that using step 3 (the value was 48% ∼ 56%). 相似文献
5.
Daniel Luciano Falkoski Valéria Monteze Guimarães Maíra Nicolau de Almeida Acelino Couto Alfenas Jorge Luiz Colodette Sebastião Tavares de Rezende 《Applied biochemistry and biotechnology》2012,166(6):1586-1603
The aim of this work was to evaluate the biochemical features of the white-rot fungi Pycnoporus sanguineus cellulolytic complex and its utilization to sugarcane bagasse hydrolysis. When cultivated under submerged fermentation using
corn cobs as carbon source, P. sanguineus produced high FPase, endoglucanase, β-glucosidase, xylanase, mannanase, α-galactosidase, α-arabinofuranosidase, and polygalacturonase
activities. Cellulase activities were characterized in relation to pH and temperature. β-Glucosidase and FPase activities
were higher at 55 °C, pH 4.5, and endoglucanase activity was higher at 60 °C, in a pH range of 3.5–4.0. All cellulase activities
were highly stable at 40 and 50 °C through 48 h of pre-incubation. Crude enzymatic extract from P. sanguineus was applied in a saccharification experiment using acid-treated and alkali-treated sugarcane bagasse as substrate, and the
hydrolysis yields were compared to that obtained by a commercial cellulase preparation. Reducing sugar yields of 60.4% and
64.0% were reached when alkali-treated bagasse was hydrolyzed by P. sanguineus extract and commercial cellulase, respectively. Considering the glucose production, it was observed that P. sanguineus extract and commercial cellulase ensured yields of 22.6% and 36.5%, respectively. The saccharification of acid-treated bagasse
was lower than that of alkali-treated bagasse regardless of the cellulolytic extract. The present work showed that P. sanguineus has a great potential as an enzyme producer for biomass saccharification. 相似文献
6.
Lactic acid production from cellulosic material by synergetic hydrolysis and fermentation 总被引:2,自引:0,他引:2
The hydrolysis process on corncob residue was catalyzed synergetically by the cellulase from Trichoderma reesei and the immobilized cellobiase. The feedback inhibition to cellulase reaction caused by the accumulation of cellobiose was
eliminated efficiently. The hydrolysis yield of corncob residue was 82.5%, and the percentage of glucose in the reducing sugar
reached 88.2%. The glucose in the cellulosic hydrolysate could be converted into lactic acid effectively by the immobilized
cells of Lactobacillus delbrueckii. When the enzymatic hydrolysis of cellulose and the fermentation of lactic acid were coupled together, no glucose was accumulated
in the reaction system, and the feedback inhibition caused by glucose was also eliminated. Under the batch process of synergetic
hydrolysis and lactic acid fermentation with 100 g/L of cellulosic substrate, the conversion efficiency of lactic acid from
cellulose and the productivity of lactic acid reached 92.4% and 0.938 g/(L·h), respectively. By using a fed-batch technique,
the total concentration of cellulosic substrate and lactic acid in the synergetic process increased to 200 and 107.5 g/L,
respectively, whereas the dosage of cellulase reduced from 20 to 15 IU/g of substrate in the batch process. The results of
the bioconversion of renewable cellulosic resources were significant. 相似文献
7.
The potential economic benefits of surfactants addition on enzymatic hydrolysis of steam-exploded lodgepole pine (SELP) and ethanol-pretreated lodgepole pine (EPLP) were investigated in this study. Free cellulase readsorption on fresh substrate was used to recover and recycle cellulase enzymes during the hydrolysis of SELP and EPLP substrate. Supplementing Tween 80 during the hydrolysis could facilitate enzyme recycling for EPLP substrate. A logarithmic correlation was established between surfactant concentration and free cellulase content after lignocellulosic hydrolysis, which was used to compute enzyme cost savings over various Tween 80 concentrations. A simple economic analysis of enzyme cost savings versus the cost of surfactant was undertaken. The results indicated that the addition of Tween 80 (priced at US $0.25/kg) during the hydrolysis of the EPLP substrate could save 60% of the total enzyme cost at concentrations in the 0.025% to 0.2% range. The addition of Tween for the hydrolysis of the SELP substrate significantly reduced the material cost by 24% per 1 gal of ethanol produced, and the ethanol production cost could be reduced by 8.6% with the addition of Tween and enzymes recycle for the hydrolysis of SELP substrate. A schematic concept of recycling enzyme and surfactant was also presented with a recirculation of process streams during hydrolysis. Further analysis indicated a 66% reduction in total enzyme cost could potentially be achieved under the concept. 相似文献
8.
Alexander V. Gusakov Arkady P. Sinitsyn Igor Yu. Davydkin Valery Yu Davydkin Oksana V. Protas 《Applied biochemistry and biotechnology》1996,56(2):141-153
The use of the intensive mass transfer reactor (IMTR) for enzymatic saccharification of cellulose, where the reaction mixture
is intensively stirred by ferromagnetic particles (FMP), enhances the process rate and productivity drastically. The most
significant enhancement of the process was observed when microcrystalline cellulose was used as a substrate. A concentration
of sugars up to 5% was obtained after 1 h of cellulose hydrolysis using a cellulase activity level of 2 filter paper units
(FPU)/mL (20 FPU/g substrate). In the hydrolysis of two types of industrial cellulosic wastes, the enhancement effects were
less pronounced. Parameters related to the IMTR design, such as the shape, dimensions, and mass of FMP, as well as the magnetic
field strength, strongly affected the process of hydrolysis. Among various kinds of FMP tested, the most efficient were found
to be cylindrical particles (0.25 x 4 mm). In general, the hydrolysis rate enhanced when the magnetic field strength increased
from 26,000 to 64,000 A/m. An optimal FMP loading existed at each level of the field strength. Hydrolyzates obtained in the
IMTR under the action ofTrichoderma reesei andPenicillium verruculosum cellulases contained glucose and cellobiose as soluble products, cellobiose being predominant (> 50%). Only when a high level
of extra Β-glucosidase was added to the IMTR (10 CBU/mL), did glucose made up more than 90% of the products. Owing to extreme
shear conditions in the IMTR, significant enzyme inactivation took place. 相似文献
9.
In biomass-to-ethanol processes a physico-chemical pretreatment of the lignocellulosic biomass is a critical requirement for enhancing the accessibility of the cellulose substrate to enzymatic attack. This report evaluates the efficacy on barley and wheat straw of three different pretreatment procedures: acid or water impregnation followed by steam explosion versus hot water extraction. The pretreatments were compared after enzyme treatment using a cellulase enzyme system, Celluclast 1.5 L from Trichoderma reesei, and a beta-glucosidase, Novozyme 188 from Aspergillus niger. Barley straw generally produced higher glucose concentrations after enzymatic hydrolysis than wheat straw. Acid or water impregnation followed by steam explosion of barley straw was the best pretreatment in terms of resulting glucose concentration in the liquid hydrolysate after enzymatic hydrolysis. When the glucose concentrations obtained after enzymatic hydrolyses were related to the potential glucose present in the pretreated residues, the highest yield, approximately 48% (g g-1), was obtained with hot water extraction pretreatment of barley straw; this pretreatment also produced highest yields for wheat straw, producing a glucose yield of approximately 39% (g g-1). Addition of extra enzyme (Celluclast 1.5 L+Novozyme 188) during enzymatic hydrolysis resulted in the highest total glucose concentrations from barley straw, 32-39 g L-1, but the relative increases in glucose yields were higher on wheat straw than on barley straw. Maldi-TOF MS analyses of supernatants of pretreated barley and wheat straw samples subjected to acid and water impregnation, respectively, and steam explosion, revealed that the water impregnated + steam-exploded samples gave a wider range of pentose oligomers than the corresponding acid-impregnated samples. 相似文献
10.
Xuliang Lin Cheng Cai Hongming Lou Xueqing Qiu Yuxia Pang Dongjie Yang 《Cellulose (London, England)》2017,24(1):61-68
Effect of cationic surfactants alkyltrimethylammonium bromide (CnTAB) with varied alkyl chain lengths on the enzymatic hydrolysis of Avicel and the surface charge of cellulase was investigated. Enzymatic hydrolysis of Avicel increased linearly from 42.1 to 61.4 % with the increase of the concentration of cetyltrimethylammonium bromide (C16TAB) logarithmically from 0.0001 to 0.01 mM, and reached a maximum value at the concentration of 0.01–0.03 mM. When the concentration was increased further, the cellulase solution became positively charged and the enzymatic hydrolysis of Avicel decreased rapidly. With the increasing alkyl chain length, CnTAB provided more proton and neutralized the negative charge of cellulase more obviously. Therefore, the required concentration of CnTAB could be less to enhance the enzymatic hydrolysis of Avicel. In addition, C16TAB could enhance enzymatic hydrolysis efficiency of corncob at high solid content from 35.0 to 56.3 %; C16TAB could reduce about 60 % of the cellulase loading in the enzymatic hydrolysis of corncob to obtain the same glucose yield. Effect of C16TAB on the enzymatic hydrolysis of typical pretreated softwood and hardwood was also investigated. This study laid the foundation for using CnTAB to recover cellulase, and provided the design direction for cellulase with higher activity and better stability by adjusting its hydrophilicity and chargeability. 相似文献
11.
A new study of the enzymatic hydrolysis of carboxymethyl cellulose with a bulk acoustic wave sensor 总被引:4,自引:0,他引:4
A new bulk acoustic wave (BAW) cellulase sensing technique, which is based on the enzymatic hydrolysis process of sodium carboxymethylcellulose (CMC) by cellulase, was established. The frequency shift curves of BAW sensor indicated that the viscosity of the tested solutions decreased during the hydrolysis process. The hydrolysis rate of CMC by cellulase was calculated from the frequency shift curves. The hydrolysis rate of CMC under different pH conditions at 30°C showed that cellulase had high hydrolysis ability approximately at pH 5.0. Kinetic parameters (the Michaelis constant Km and the maximum rate Vmax) of the process were estimated by using a linear method of Lineweaver–Burk plot. Km is 1.95±0.25 mg ml−1 and Vmax is −(4.25±0.58)×10−3 g1/2 cm−3/2 cP1/2 min−1. Also the activation energy (Ea) of the enzymatic hydrolysis, with a value of 51.99±1.26 kJ mol−1, was estimated in this work. 相似文献
12.
Chao Zhang Xinshu Zhuang Zhao Jiang Wang Fred Matt Franz St. John J. Y. Zhu 《Cellulose (London, England)》2013,20(4):1937-1946
Three pairs of solid substrates from dilute acid pretreatment of two poplar wood samples were enzymatically hydrolyzed by cellulase preparations supplemented with xylanase. Supplementation of xylanase improved cellulose saccharification perhaps due to improved cellulose accessibility by xylan hydrolysis. Total xylan removal directly affected enzymatic cellulose saccharification. Furthermore, xylan removal by pretreatment and xylanase are indifferent to enzymatic cellulose saccharification. However, more enzymatic xylose and glucose yields were obtained for a substrate with lower xylan content after a severer pretreatment at the same xylanase dosage. The effectiveness of xylanase at increased dosages depended on the substrates structure or accessibility. High xylanase dosages were more effective on well pretreated substrates than on under-pretreated substrates with high xylan content. The application sequence of xylanase and cellulase affected cellulose saccharification. This effect varied with substrate accessibility, perhaps due to competition between xylanase and cellulase binding to the substrate. 相似文献
13.
Sweet sorghum bagasse (SSB) was steam pretreated in the conditions of 190 °C for 5 min to assess its amenability to the pretreatment and enzymatic hydrolysis. Results showed that pretreatment conditions were robust enough to pretreat SSB with maximum of 87% glucan and 72% xylan recovery. Subsequent enzymatic hydrolysis showed that the pretreated SSB at 2% substrate consistency resulted in maximum of 70% glucan-glucose conversion. Increasing substrate consistency from 2% to 16% led to a significant reduction in glucan conversion. However, the decrease ratio of glucan-glucose conversion was the minimum when the consistency increased from 2% to 12%. When the pretreated SSB consistency of 12% was applied for hydrolysis, increase in cellulase loading from 7.5 up to 20 filter paper units (FPU)/g glucan resulted only in 14% increase in glucan-glucose conversion compared to 20% increase with cellulase loading varying from 2.5 to 7.5 FPU/g glucan. More than 10 cellobiase units (CBU)/g glucan β-glucosidase supplementation had no noticeable improvement on glucan-glucose conversion. Additionally, supplementation of xylanase was found to significantly increase glucan-glucose conversion from 50% to 80% with the substrate consistency of 12%, when the cellulase and β-glucosidase loadings were at relatively low enzyme loadings (7.5 FPU/g and 10 CBU/g glucan). It appeared that residual xylan played a critical role in hindering the ease of hydrolysis of SSB. A proper xylanase addition was suggested to achieve a high hydrolysis yield at relatively high substrate consistency with relatively low enzyme loadings. 相似文献
14.
Wei Liao Zhiyou Wen Sharon Hurley Yan Liu Chuanbin Liu Shulin Chen 《Applied biochemistry and biotechnology》2005,124(1-3):1017-1030
This study focused on the effect of hemicellulose and lignin on enzymatic hydrolysis of dairy manure and hydrolysis process
optimization to improve sugar yield. It was found that hemicellulose and lignin in dairy manure, similar to their role in
other lignocellulosic material, were major resistive factors to enzymatic hydrolysis and that the removal of either of them,
or for best performance, both of them, improved the enzymatic hydrolysis of manure cellulose. This result combined with scanning
electron microscope (SEM) pictures further proved that the accessibility of cellulose to cellulase was the most important
feature to the hydrolysis. Quantitatively, fed-batch enzymatic hydrolysis of fiber without lignin and hemicellulose had a
high glucose yield of 52% with respect to the glucose concentration of 17 g/L at a total enzyme loading of 1300 FPU/L and
reaction time of 160 h, which was better than corresponding batch enzymatic hydrolysis. 相似文献
15.
Soybean hulls were subjected to thermo-mechanical extrusion pretreatment at various in-barrel moisture contents and screw
speeds. Extrusion degraded the lignocellulosic structure and enhanced enzymatic hydrolysis of soybean hulls, with up to 155%
increase in glucose yield as compared to untreated substrate. Greater glucose yields were observed at higher in-barrel moistures
(45% and 50%) and lower screw speed (280 and 350 rpm). Maximum 74% cellulose to glucose conversion resulted from using a two-enzyme
cocktail consisting of cellulase and β-glucosidase. Conversion increased to 87% when a three-enzyme cocktail having a cell
wall degrading enzyme complex was used for hydrolysis. Fermentation inhibitors, such as furfural, 5-(hydroxymethyl)-2-furaldehyde
(HMF), and acetic acid, were found in the extrusion pretreated soybean hulls and hydrolysate. However, their concentrations
were below the known thresholds for inhibition. Fermentation of hydrolysate by Saccharomyces cerevisiae led to high yields of ethanol, with concentration ranging from 13.04 to 15.44 g/L. 相似文献
16.
Hui Wang Kazuhiro Mochidzuki Shinichi Kobayashi Hatsue Hiraide Xiaofen Wang Zongjun Cui 《Applied biochemistry and biotechnology》2013,170(3):541-551
Bovine serum albumin (BSA) was added to filter paper during the hydrolysis of cellulase. Adding BSA before the addition of the cellulase enhances enzyme activity in the solution, thereby increasing the conversion rate of cellulose. After 48 h of BSA treatment, the BSA adsorption quantities are 3.3, 4.6, 7.8, 17.2, and 28.3 mg/g substrate, each with different initial BSA concentration treatments at 50 °C; in addition, more cellulase was adsorbed onto the filter paper at 50 °C compared with 35 °C. After 48 h of hydrolysis, the free-enzyme activity could not be measured without the BSA treatment, whereas the remaining activity of the filter paper activity was approximately 41 % when treated with 1.0 mg/mL BSA. Even after 96 h of hydrolysis, 25 % still remained. Meanwhile, after 48 h of incubation without substrate, the remaining enzyme activities were increased 20.7 % (from 43.7 to 52.7 %) and 94.8 % (from 23.3 to 45.5 %) at 35 and 50 °C, respectively. Moreover, the effect of the BSA was more obvious at 35 °C compared with 50 °C. When using 15 filter paper cellulase units per gram substrate cellulase loading at 50 °C, the cellulose conversion was increased from 75 % (without BSA treatment) to ≥90 % when using BSA dosages between 0.1 and 1.5 mg/mL. Overall, these results suggest that there are promising strategies for BSA treatment in the reduction of enzyme requirements during the hydrolysis of cellulose. 相似文献
17.
Cellulase retention and sugar removal by membrane ultrafiltration during lignocellulosic biomass hydrolysis 总被引:1,自引:0,他引:1
Technologies suitable for the separation and reuse of cellulase enzymes during the enzymatic saccharification of pretreated
corn stover are investigated to examine the economic and technical viability of processes that promote cellulase reuse while
removing inhibitory reaction products such as glucose and cellobiose. The simplest and most suitable separation is a filter
with relatively large pores on the order of 20–25 mm that retains residual corn stover solids while passing reaction products
such as glucose and cellobiose to form a sugar stream for a variety of end uses. Such a simple separation is effective because
cellulase remains bound to the residual solids. Ultrafiltration using 50-kDa polyethersulfone membranes to recover cellulase
enzymes in solution was shown not to enhance further the saccharification rate or overall conversion. Instead, it appears
that the necessary cellulase enzymes, including β-glucosidase, are tightly bound to the substrate; when fresh corn stover
is contacted with highly washed residual solids, without the addition of fresh enzymes, glucose is generated at a high rate.
When filtration was applied multiple times, the concentration of inhibitory reaction products such as glucose and cellobiose
was reduced from 70 to 10 g/L. However, an enhanced saccharification performance was not observed, most likely because the
concentration of the inhibitory products remained too high. Further reduction in the product concentration was not investigated,
because it would make the reaction unnecessarily complex and result in a product stream that is much too dilute to be useful.
Finally, an economic analysis shows that reuse of cellulase can reduce glucose production costs, especially when the enzyme
price is high. The most economic performance is shown to occur when the cellulase enzyme is reused and a small amount of fresh
enzyme is added after each separation step to replace lost or deactivated enzyme. 相似文献
18.
Current technology for conversion of biomass to ethanol is an enzyme-based biochemical process. In bioethanol production,
achieving high sugar yield at high solid loading in enzymatic hydrolysis step is important from both technical and economic
viewpoints. Enzymatic hydrolysis of cellulosic substrates is affected by many parameters, including an unexplained behavior
that the glucan digestibility of substrates by cellulase decreased under high solid loadings. A comprehensive study was conducted
to investigate this phenomenon by using Spezyme CP and Avicel as model cellulase and cellulose substrate, respectively. The
hydrolytic properties of the cellulase under different substrate concentrations at a fixed enzyme-to-substrate ratio were
characterized. The results indicate that decreased sugar yield is neither due to the loss of enzyme activity at a high substrate
concentration nor due to the higher end-product inhibition. The cellulase adsorption kinetics and isotherm studies indicated
that a decline in the binding capacity of cellulase may explain the long-observed but little-understood phenomenon of a lower
substrate digestibility with increased substrate concentration. The mechanism how the enzyme adsorption properties changed
at high substrate concentration was also discussed in the context of exploring the improvement of the cellulase-binding capacity
at high substrate loading. 相似文献
19.
Hongming Lou Haifeng Zhou Xiuli Li Mengxia Wang J. Y. Zhu Xueqing Qiu 《Cellulose (London, England)》2014,21(3):1351-1359
The effects of lignosulfonate (LS) on enzymatic saccharification of pure cellulose were studied. Four fractions of LS with different molecular weight (MW) prepared by ultrafiltration of a commercial LS were applied at different loadings to enzymatic hydrolysis of Whatman paper under different pH. Using LS fractions with low MW and high degree of sulfonation can enhance enzymatic cellulose saccharification despite LS can bind to cellulase nonproductively. The enhancing effect varies with LS properties, its loading, and hydrolysis pH. Inhibitive effect on cellulose saccharification was also observed using LS with large MW and low degree of sulfonation. The concept of “LS-cellulase aggregate stabilized and enhanced cellulase binding” was proposed to explain the observed enhancement of cellulose saccharification. The concept was demonstrated by the linear correlation between the measured amount of bound cellulase and saccharification efficiency with and without LS of different MW in a range of pH. 相似文献
20.
纤维素废弃物的生物转化 总被引:3,自引:0,他引:3
从纤维素酶法水解出发,叙述了纤维废弃物生物转化为葡萄糖和乙醇的研究现状和发展趋势,重点说明了加快反应速率、提高纤维素酶利用率的几种方法。 相似文献