Effect of inhibitors released during steam-explosion pretreatment of barley straw on enzymatic hydrolysis

The influence of the liquid fraction (prehydrolysate) generated during steam-explosion pretreatment (210°C, 15 min) of barley straw on the enzymatic hydrolysis was determined. Prehydrolysate was analyzed for degradation compounds and sugars' content and used as a medium for enzymatic hydrolysis tests after pH adjusting to 4.8. Our results show that the presence of the compounds contained in the prehydrolysate strongly affects the hydrolysis step (a 25% decrease in cellulose conversion compared with control). Sugars are shown to be more potent inhibitors of enzymatic hydrolysis than degradation products.     

Model-based fed-batch for high-solids enzymatic cellulose hydrolysis

While many kinetic models have been developed for the enzymatic hydrolysis of cellulose, few have been extensively applied for process design, optimization, or control. High-solids operation of the enzymatic hydrolysis of lignocellulose is motivated by both its operation decreasing capital costs and increasing product concentration and hence separation costs. This work utilizes both insights obtained from experimental work and kinetic modeling to develop an optimization strategy for cellulose saccharification at insoluble solids levels greater than 15% (w/w), where mixing in stirred tank reactors (STRs) becomes problematic. A previously developed model for batch enzymatic hydrolysis of cellulose was modified to consider the effects of feeding in the context of fed-batch operation. By solving the set of model differential equations, a feeding profile was developed to maintain the insoluble solids concentration at a constant or manageable level throughout the course of the reaction. Using this approach, a stream of relatively concentrated solids (and cellulase enzymes) can be used to increase the final sugar concentration within the reactor without requiring the high initial levels of insoluble solids that would be required if the operation were performed in batch mode. Experimental application in bench-scale STRs using a feed stream of dilute acid-pretreated corn stover solids and cellulase enzymes resulted in similar cellulose conversion profiles to those achieved in batch shake-flask reactors where temperature control issues are mitigated. Final cellulose conversions reached approximately 80% of theoretical for fed-batch STRs fed to reach a cumulative solids level of 25% (w/w) initial insoluble solids.     

Mitigation of cellulose recalcitrance to enzymatic hydrolysis by ionic liquid pretreatment

Efficient hydrolysis of cellulose-to-glucose is critically important in producing fuels and chemicals from renewable feedstocks. Cellulose hydrolysis in aqueous media suffers from slow reaction rates because cellulose is a water-insoluble crystalline biopolymer. The high-crystallinity of cellulose fibrils renders the internal surface of cellulose inaccessible to the hydrolyzing enzymes (cellulases) as well as water. Pretreatment methods, which increase the surface area accessible to water and cellulases are vital to improving the hydrolysis kinetics and conversion of cellulose to glucose. In a novel technique, the microcrystalline cellulose was first subjected to an ionic liquid (IL) treatment and then recovered as essentially amorphous or as a mixture of amorphous and partially crystalline cellulose by rapidly quenching the solution with an antisolvent. Because of their extremely low-volatility, ILs are expected to have minimal environmental impact. Two different ILs, 1-n-butyl-3-methylimidazolium chloride (BMIMC1) and 1-allyl-3-methylimidazolium chloride (AMIMC1) were investigated. Hydrolysis kinetics of the IL-treated cellulose is significantly enhanced. With appropriate selection of IL treatment conditions and enzymes, the initial hydrolysis rates for IL-treated cellulose were up to 90 times greater than those of untreated cellulose. We infer that this drastic improvement in the "overall hydrolysis rates" with IL-treated cellulose is mainly because of a significant enhancement in the kinetics of the "primary hydrolysis step" (conversion of solid cellulose to soluble oligomers), which is the rate-limiting step for untreated cellulose. Thus, with IL-treated cellulose, primary hydrolysis rates increase and become comparable with the rates of inherently faster "secondary hydrolysis" (conversion of soluble oligomers to glucose).     

Biological pretreatment of lignocellulose for enzymatic hydrolysis of cellulose

Pretreatment of lignocellulosic materials is considered as the rate-limiting step in an economically feasible process for enzymatic hydrolysis of cellulose. Biological delignification techniques have not been developed as intensively as physical and chemical methods. However, white-rot fungi are effective degraders of lignin, and some of them even preferentially remove lignin from wood compared with carbohydrates, and therefore might be suitable for biological pretreatment of lignocellulose. White-rot fungi were cultivated on wheat straw and the residue was hydrolyzed withTrichoderma reesei cellulase. Of nineteen fungi examined,Pleurotus ostreatus, Pleurotus sp. 535,Pycnoporus cinnabarinus 115,Ischnoderma benzoinum 108,Phanerochaete sordida 37,Phlebia radiata 79, and two unidentified fungi were found suitable for pretreatment of straw: the yields of reducing sugars and glucose based on original straw were markedly better compared with uninoculated straw, and these fungi also gave better results thanPolyporus versicolor, a nonselective reference fungus (Cowling, 1961). In the best cases the efficiency of the biological pretreatment was comparable with that of alkali treatment (2% NaOH, 0.4 g NaOH/g straw, 10 min at 115‡C), but the fungal treatment resulted in a higher proportion of glucose in the hydrolyzates. Combined fungal and (strong) alkali treatment did not give better results than alkali or fungal treatment alone. When culture flasks were periodically flushed with oxygen the treatment time could be reduced by about 1 wk with the two fungi,P. sordida 37 andP. cinnabarinus 115, tested. The effect of oxygen in pretreatment reflected the effect of oxygen in the degradation of¹⁴C-lignin of poplar wood to¹⁴CO₂ by these fungi (Hatakka and Uusi-Rauva, 1983). The economic feasibility of the biological pretreatment process is poor due to the long cultivation times needed. The best results were obtained with the longest treatment time studied, which was 5 wk. However, the rapid progress in the field of biological lignin degradation may help to accelerate the delignification process, and also find factors that favor lignin degradation, but suppress the utilization of carbohydrates.     

Interfacial properties of cellulose nanoparticles obtained from acid and enzymatic hydrolysis of cellulose

Rod-shaped cellulose nanocrystals obtained by acid hydrolysis of eucalyptus fibers (CNCa) presented high aspect ratio (estimated length and width of 180 and 5 nm, respectively) and zeta potential of ?(17 ± 1) mV at pH 6. This typical morphology of cellulose nanocrystals was in contrast to nanoparticles obtained upon enzymatic hydrolysis of bacterial cellulose (CNCe), which were asymmetric and irregular due to surface-bound cellulases and presented a distinctive surface roughness. Interestingly, CNCe also displayed axial grooves, to yield a C-shape cross section that has not been reported before. The effect of the characteristic shape and surface chemistry of CNCa and of grooved CNCe was studied at oil/water interfaces and solid surfaces. Emulsions (20 % v/v oil) prepared with the CNCa were more stable than those prepared with CNCe, owing to their characteristic shape and surface chemistry. Hydrophilic (silica surfaces cationized by pre-adsorbed polycation) and hydrophobic (polystyrene films) solid surfaces were used as substrates for the adsorption of CNCe and CNCa for each type of surface. The ellipsometric data and AFM images indicated larger affinity of CNCe than CNCa for the hydrophobic surface. On the other hand, CNCa formed homogeneous monolayer on hydrophilic surfaces, whereas CNCe formed discontinuous films. Sequential adsorption behavior of CNCa on CNCe layers (or vice versa) suggested that the interaction between them is controlled by the orientation of enzymes bound to CNCe.     

Observations on the complex interactions involved in the enzymatic hydrolysis of cellulose

Although fractionation studies performed on the cellulases of the fungiPencillium funiculosum, Trichoderma koningii, andFusarium solani have shown that the solubilization of high ordered crystalline cellulose can be effected by mixtures of endo-1,4-Β-glucanase, cellobiohydrolase, and Β-glucosidase, factors that affect the interaction of these enzymes are not well understood. Sequential action between endo-1,4-Β-glucanase and cellobiohydrolase is almost certainly a feature of these cellulase systems, but experimental observations would suggest that it is not possible to discuss the mechanism purely in these terms. Some of the steric problems confronting the enzymes may explain, in part, many of the anomalous observations recorded. The cellulase ofP. funiculosum is of special interest in that, in addition to four endo-1,4-Β-glucanases and two Β-glucosidases, it contains two cellobiohydrolases and a glucohydrolase. A detailed study of all these enzymes has not yet been carried out, but several properties of the glucohydrolase and cellobiohydrolase are worthy of note. The glucohydrolase, in being strongly inhibited by glucono-1,5-lactone, in possessing transferase activity and in exhibiting activity on all other Β-linked, glucose disaccharides, had several properties normally associated with Β-glucosidases. It could be distinguished from the Β-glucosidases, however, in retaining anomeric configuration during hydrolysis and in being able to attack long glucan chains. The glucohydrolase was unable to cooperate with the endo- 1,4-Β-glucanase in solubilizing cotton cellulose and this contrasts with the high degree of cooperation shown by the cellobiohydrolase and endo-l,4-Β-glucanase in effecting the extensive solubilization of this substrate. The observation that an enzyme that removes two glucose units (cellobiohydrolase) from the end of the cellulose chain can act synergistically with the endo-l,4-Β-glucanase, but an enzyme that removes only one (glucohydrolase) cannot, must be connected in some way with steric rigidity of the anhydroglucose unit in the cellulose crystallite and the fact that cellobiose is the repeating unit. Recently, studies have been extended to the two cellobiohydrolases ofP. funiculosum. Not surprisingly, it was found that the cellobiohydrolase enzymes had no capacity for cooperating to solubilize cotton cellulose. However, it was unexpected to find that they acted synergistically in degrading the microcrystalline cellulose, Avicel. Two immunologically unrelated cellobiohydrolases have been found recently in cultures of the fungusTrichoderma reesei. Experiments are now in progress to determine whether the two cellobiohydrolases ofP. funiculosum are also immunologically different. However, even if the cellobiohydrolases prove to be merely isoenzymes, the observation with Avicel is an unusual one. It has already been observed that the cellobiohydrolase of one fungus can act synergistically with the endo-1,4-Β-glucanase of another in solubilizing highly ordered cellulose. However, when fungal cellobiohydrolases were added to the endo-1,4-Β-glucanase of the rumen bacteriaRuminococcus albus,Ruminococcus flavefaciens, andBacteroides succinogenes, no synergism was observed. One interpretation of this would be that these bacteria use mechanisms of cellulase action different from that used in the fungi.     

Factors to decrease the cellulose conversion of enzymatic hydrolysis of lignocellulose at high solid concentrations

The enzymatic hydrolysis of lignocelluloses is a key step in the production of ethanol. Economic considerations for large-scale implementation of the process require operation at high solid concentrations. However, the decrease in cellulose conversion offsets the advantages of working at high solid concentrations. The conversion showed a linear decrease in the reaction of pretreated corn stover (PCS) from 2 to 20 % (w/w) and filter paper from 1 to 10 % (w/w) initial total solid content. Hydrolysis experiments with PCS at various mixing speeds showed that the mass transfer limitation could not restrict the cellulose conversion except the solid concentrations over 5 % DM(w/w). The lignin, if added separately, does not correspond directly to the decrease. At increased concentrations, furfural and 5-hydroxymethylfurfural played a part in the effect, and 5-hydroxymethylfurfural only affected exoglucanase. Product inhibition caused by glucose accumulation at increased solid concentrations was found to be a significant and perhaps principal factor. The decrease in yield was caused by the synergetic inhibition, which was more serious with increased solid concentrations.     

Effect of cationic surfactant cetyltrimethylammonium bromide on the enzymatic hydrolysis of cellulose

Effect of cationic surfactants alkyltrimethylammonium bromide (C_nTAB) 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, C_nTAB provided more proton and neutralized the negative charge of cellulase more obviously. Therefore, the required concentration of C_nTAB 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 C_nTAB to recover cellulase, and provided the design direction for cellulase with higher activity and better stability by adjusting its hydrophilicity and chargeability.     

Optimization of steam explosion to enhance hemicellulose recovery and enzymatic hydrolysis of cellulose in softwoods

A combination of Douglas fir heartwood and sapwood chips were steam pretreated under three conditions as measured by the Severity Factor (log R_o), which incorporated the time, temperature/pressure of pretreatment. By adjusting the steam pretreatment conditions, it was hoped to recover the majority of the hemicellulose component as monomers in the water-soluble stream, while providing a cellulosic-rich, water-insoluble fraction that could be readily hydrolyzed by cellulases. These three conditions were chosen to represent either high hemicellulose sugar recovery (low severity [L], log R_o=3.08), high-enzyme hydrolyzability of the cellulosic component (high severity [H], log R_o=4.21), and a compromise between the two conditions (medium severity [M], log R_o=3.45). The medium-severity pretreatment conditions (195°C, 4.5 min, 4.5% SO₂ logR_o=3.45) gave the best compromise in terms of relatively high hemicellulose recovery after stream pretreatment and the subsequent efficiency of enzymatic hydrolysis of the water-insoluble cellulosic fraction. The percent recovery of the original hemicellulose in the water-soluble fraction dropped significantly when the severity was increased (L-76.8%, M-64.7%, and H-37.5%). However, the ease of enzymatic hydrolysis of the cellulose-rich, water-insoluble fraction increased with increasing severity (L-24%, M-86.6%, and H-97.9%). Although more severe pretreatment conditions provided optimum hydrolysis of the cellulosic component, less severe conditions resulted in better recovery of the combined hemicellulose and cellulosic components.     

Bioethanol from cellulose with supercritical water treatment followed by enzymatic hydrolysis

The water-soluble portion and precipitates obtained by supercritical (SC) water treatment of microcrystalline cellulose (Avicel) were enzymatically hydrolyzed. Glucose could be produced easily from both substrates, compared with the Avicel. Therefore, SC water treatment was found to be effective for enhancing the productivity of glucose from cellulose by the enzymatic hydrolysis. It is also found that alkaline treatment or wood charcoal treatment reduced inhibitory effects by various decomposed compounds of cellulose on the enzymatic hydrolysis to achieve higher glucose yields. Furthermore, glucose obtained by SC water treatment followed by the enzymatic hydrolysis of cellulose could be converted to ethanol by fermentation without any inhibition.     

Effects of hemicellulose and lignin on enzymatic hydrolysis of cellulose from dairy manure

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.     

Effect of alkaline ultrasonic pretreatment on crystalline morphology and enzymatic hydrolysis of cellulose

In this study, ultrasound-assisted alkaline pretreatment is developed to evaluate the morphological and structural changes that occur during pretreatment of cellulose, and its effect on glucose production via enzymatic hydrolysis. The pretreated samples were characterized using scanning electron microscopy, infrared spectroscopy, and X-ray diffraction to understand the change in surface morphology, crystallinity and the fraction of cellulose Iβ and cellulose II. The combined pretreatment led to a great disruption of cellulose particles along with the formation of large pores and partial fibrillation. The effects of ultrasound irradiation time (2, 4 h), NaOH concentration (1–10 wt%), initial particle size (20–180 μm) and initial degree of polymerization (DP) of cellulose on structural changes and glucose yields were evaluated. The alkaline ultrasonic pretreatment resulted in a significant decrease in particle size of cellulose, besides significantly reducing the treatment time and NaOH concentration required to achieve a low crystallinity of cellulose. More than 2.5 times improvement in glucose yield was observed with 10 wt% NaOH and 4 h of sonication, compared to untreated samples. The glucose yields increased with increase in initial particle size of cellulose, while DP had no effect on glucose yields. The glucose yields exhibited an increasing tendency with increase in cellulose II fraction as a result of combined pretreatment.     

Enhancing enzymatic hydrolysis of crystalline cellulose and lignocellulose by adding long-chain fatty alcohols

The effects of long-chain fatty alcohols (LFAs) on the enzymatic hydrolysis of crystalline cellulose by two commercial Trichoderma reesei cellulase cocktails (CTec2 and Celluclast 1.5L) were studied. It was found that n-butanol inhibited the enzymatic hydrolysis, but n-octanol, n-decanol and n-dodecanol had strong enhancement on enzymatic hydrolysis of crystalline cellulose in the buffer pH range from 4.0 to 6.0. LFAs can increase the hydrolysis efficiency of crystalline cellulose from 37 to 57 % at Celluclast 1.5L loading of ten filter paper units (FPU)/g glucan. LFAs have similar enhancement on the enzymatic hydrolysis of crystalline cellulose mixed with lignin or xylan. The enhancement of LFAs increased with the decrease of the crystallinity index. LFAs not only enhanced the high-solid enzymatic hydrolysis of lignocellulose, but also improved the rheological properties of high-solid lignocellulosic slurries by decreasing the yield stress and complex viscosity. Meanwhile, LFAs can improve the enzymatic hydrolysis of cellobiose to glucose, especially at low cellulase loading.     

Cellulose loading and water sorption value as important parameters for the enzymatic hydrolysis of cellulose

The enzymatic hydrolysis of cotton raw cellulose (RC) samples, sieved RC samples through meshes <100 (CS1), 100–200 (C12), 200–400 (C24), mercerized RC samples (M-C), freeze-dried RC (RC-FD) samples, microcrystalline cellulose Avicel, bacterial cellulose (BC), raw sisal pulp and mercerized sisal pulp (S-M) was performed at cellulose-to-cellulase mass ratios of 1,000:1, 699:1, 400:1, 100:1 and 10:1. The index of crystallinity and water sorption values were quantified for all samples. The morphological features were analyzed by means of scanning electron microscopy (SEM). For cellulose-to-cellulase mass ratio of 100:1 and 10:1, the maximum hydrolysis extents of cellulose samples after 24 h reaction could not be correlated with their physical characteristics. However, hydrolyses of samples with large water sorption values were faster than those with lower water sorption values. The hydrolysis efficiency decreased when the cellulose-to-cellulase mass ratio was greater than 400:1; under this condition a remarkable dependence of the hydrolysis yield on the type of cellulosic sample was observed. The water sorption ability could be directly correlated with the hydrolysis extent, except for RC-FD and BC samples, which presented the lowest values. In the former, freeze-drying has led to pore collapse, with concomitant reduction of the amount of adsorbed water. For the latter sample, the densely packed structure made the water sorption slower than in all other samples. Despite of this fact, the presence of nanofibrils on the surface of BC (as detected by SEM) improved the enzyme adsorption, indicating that analysis by complementary techniques should be performed in order to predict the enzymatic hydrolysis efficiency.     

Kinetics of enzymatic hydrolysis of lignocellulosic materials based on surface area of cellulose accessible to enzyme and enzyme adsorption on lignin and cellulose

Comparison of the model with experimental data is currently in progress. It appears that more detailed studies of the adsorption dynamics, not just adsorption equilibrium, are needed.     

A new study of the enzymatic hydrolysis of carboxymethyl cellulose with a bulk acoustic wave sensor

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 K_m and the maximum rate V_max) of the process were estimated by using a linear method of Lineweaver–Burk plot. K_m is 1.95±0.25 mg ml⁻¹ and V_max is −(4.25±0.58)×10⁻³ g^1/2 cm^−3/2 cP^1/2 min⁻¹. Also the activation energy (E_a) of the enzymatic hydrolysis, with a value of 51.99±1.26 kJ mol⁻¹, was estimated in this work.     

Effect of structural and physico-chemical features of cellulosic substrates on the efficiency of enzymatic hydrolysis

Effects of major physicochemical and structural parameters of cellulose on the rate and degree of its enzymatic hydrolysis were tested with cellulosic materials from various sources. Some different pretreatments were: mechanical (milling), physical (X-ray irradiation), and chemical (cadoxen, H₃PO₄, H₂SO₄, NaOH, Fe²+/H₂O₂). The average size of cellulose particles and its degree of polymerization had little effect on the efficiency of enzymatic hydrolysis. For samples of pure cellulose (cotton linter, microcrystalline cellulose, α-cellulose), increase in the specific surface area accessible to protein molecules and decrease in the crystallinity index accelerated the enzymatic hydrolysis (the correlation coefficients were 0.89 and 0.92, respectively). In the case of lignocellulose (bagasse), a quantitative linear relationship only between specific surface area and reactivity was observed.     

An extension of the Harano-Ooshima rate expression for enzymatic hydrolysis of cellulose to account for changes in the amount of adsorbed cellulase

Three empirical rate expressions, Kinetics I, II, and III, for the enzymatic hydrolysis of cellulose were evaluated in an effort to develop a easy-to-use rate expression. They are based on the following equation:-dV/dX = kV, where V and X are the hydrolysis rate and the fractional conversion. In Kinetic I,k is constant. In Kinetic II, a linear relatinship betweenk and t is assumed. In Kinetic III, an exponential relationship is assumed. The three expressions were applied to enzymatic hydrolysis carried out under seven different conditions in which the kinds of substrates, enzymes, and initial concentrations were varied. All of the examined rate expressions were applied to the hydrolysis with success, but the better accuracies were obtained by Kinetic III, Kinetic II, and Kinetic I in this order. The variations ofk with time found in this study, especially the exponential relationship, were consistent with the effect of the measured changes in the concentration of adsorbed enzyme as predicted by theory developed previously by Ooshima et al. (1).     

Effect of hydrolysis degree of hydrolyzed polyacrylamide grafted carboxymethyl cellulose on dye removal efficiency

In this present work, a series of hydrolyzed polyacrylamide grafted carboxymethyl cellulose (CMC-g-HPAM) was prepared. The structure and solution properties of CMC-g-HPAM were characterized by FTIR, ¹H-NMR, elemental analysis and zeta potential measurements. The graft copolymers were applied as flocculants to remove methylene blue (MB), a cationic dye, from aqueous solutions. In comparison with its precursors, carboxymethyl cellulose (CMC) and polyacrylamide CMC-g-PAM, CMC-g-HPAM exhibited higher removal efficiencies. Furthermore, the flocculation performance of the copolymers was significantly improved with the increase of the hydrolysis degree, and the MB removal efficiency was more than 90 % when the hydrolysis degree of CMC-g-HPAM was higher than 80 %. More importantly, image analysis in combination with fractal theory demonstrated that the graft copolymers could produce notably denser and larger flocs, which was of great significance in practical water treatment. The improved flocculation performance was ascribed to both charge neutralization and bridging effects.     

Enzymatic hydrolysis of cellulose hydrates

We prepared two cellulose hydrates, Na-cellulose IV and cellulose II hydrate, along with their respective anhydrous forms, cellulose II and II′, from microcrystalline cellulose. X-ray diffractometry analysis showed that the structure of the hydrophobic stacking sheet was conserved in the samples, but the distance between the sheets was in the order: cellulose II hydrate > Na-cellulose IV > cellulose II and II′. The hydrates exhibited an expanded structure compared with the anhydrous form from the incorporation of hydrate water, and cellulose II hydrate contained more hydrate water than Na-cellulose IV. Enzymatic hydrolysis of the samples was carried out at 37 °C using solutions comprising a mixture of cellulase and β-glucosidase. The hydrates were hydrolyzed more efficiently than the anhydrous forms, and cellulose II hydrate showed a more efficient hydrolysis than Na-cellulose IV. This result also agrees well with the enzymatic adsorption properties of each sample, where the samples that adsorbed the greater amount of enzyme showed a higher degradability. The results obtained in this study provide useful knowledge on controlling the biodegradability of cellulose by converting its structure.