Maximum Glucose Yield Research Articles

Study on cellulose (96% crystalline) hydrolysis performance of sulfonated carbon catalyst in microwave-heated reactor at elevated temperatures

In this work, the combined effects of microwave reactor and sulfonated bamboo catalyst in the hydrolysis of previously untreated cellulose (96% of crystallinity with 3.61 nm average crystallite size) at higher temperature were studied. The synthesized catalyst was characterized by FTIR, XRD, SEM, elemental analysis, TGA coupled with mass spectrophotometer, ammonia temperature-programmed desorption, total acid content (titration method), and surface area analyzer (surface area, total pore volume, and pore size). The catlyst activity and selectivity was tested through hydrolysis of untreated crystalline cellulose, in which the conversion and the yield were analyzed by TOC and HPLC. The acid density of the prepared catalyst due to SO3H group was found to be 0.54 mmol/g with an elemental sulfur content of 2%. The maximum yield of glucose found was around 43.5% at a reaction temperature of 180 °C and 60 min of reaction time, using a microwave reactor. Similar conversion and glucose yield were attained in second run showing the reusable potential of the catalyst. Moreover, the combined effects of the catalyst and the microwave reactor gave a higher yield of glucose from crystalline cellulose. The catalyst has shown its potential to convert glucose further into platform chemicals like hydroxymethylfurfural, levulinic acid, and formic acid.

The Effect of Lignin Content in Birch and Beech Kraft Cellulosic Pulps on Simple Sugar Yields from the Enzymatic Hydrolysis of Cellulose

The results of enzymatic hydrolysis of birch and beech kraft cellulosic pulps indicate that they may be promising feedstocks for fermentation processes including biofuel manufacturing. The aim of this study was to investigate whether birch and beech wood require the same degree of delignification by kraft pulping as pine wood. The differences observed in the efficiency of hydrolysis for the raw materials tested suggest that the differences in the anatomical structure of the examined wood in relation to pine wood is essential for the efficiency of the enzymatic hydrolysis process. The yields of glucose and other reducing sugars obtained from the birch and beech cellulosic pulps were similar (up to around 75% and 98.3% dry weight, and 76% and 98.6% dry weight, respectively). The highest glucose yields from cellulose contained in the birch and beech pulp were around 81.2% (at a Kappa number of 28.3) and 83.1% (at a Kappa number of 30.4), respectively. The maximum glucose yields and total reducing sugars of birch wood on a dry weight basis (39.8% and 52.1%, respectively) were derived from the pulp at a Kappa number of 28.3, while the highest yields of glucose and total reducing sugars of beech wood on a dry weight basis (around 36.9% and 48.2%, respectively) were reached from the pulp at a Kappa number of 25.3. To obtain the highest glucose yields and total reducing sugars of a wood on a dry weight basis, total lignin elimination from the birch and beech pulps was not necessary. However more in-depth delignification of birch and beech wood is required than for pine wood.

Microwave-Assisted Hydrolysis of Cotton Waste to Glucose in Combination with the Concentrated Sulfuric Acid Impregnation Method

Direct hydrolysis of a towel to glucose was investigated using microwave-assisted (MW) treatment combined with impregnation in concentrated sulfuric acid (SA) solution (51 wt% for 30 min) before the MW treatment. The maximum glucose yield by direct hydrolysis of an untreated towel was 30.9%, obtained at a heating temperature of 200 °C for 2 min. The maximum total glucose yield (from both direct hydrolysis and enzymatic hydrolysis of treated residue) was 74.2%, attained at a microwave heating temperature of 180 °C for 3 min. This condition is milder than that of MW treatment without impregnation in concentrated SA (our previous study, heating temperature of 200 °C for 7 min required). As shown by XRD of the unimpregnated and impregnated towels (in 9 and 36 wt% SA solution), the crystallinity index value decreased with the increase in SA concentration. Finally, 22.4 g of ethanol could be produced using the supernatant (containing glucose) and the microwave-treated residue as a carbon source for Saccharomyces cerevisiae, with less fermentation inhibition. Thus, impregnation in concentrated SA before MW treatment is effective for the production of glucose from cellulosic material and has low energy input.

Acid-catalysed hydrolysis kinetics of sugar cane bagasse to glucose and xylose in selected ionic liquid media

The process of converting lignocellulosic biomass to fuels (such as ethanol) is considered a potential method for supplanting current fossil fuels with renewable sources. A significant inhibitor to such processes is the lack of an efficient and economical means by which hemicellulose and cellulose may be hydrolysed to their constituent monosaccharides as precursors for ethanol fermentation. This research details experiments conducted by which sugar cane bagasse (SCB) immersed in ionic liquids (either 1-butyl-3-methylimidazolium chloride or 1-ethyl-3-methylimidazolium chloride – BmimCl and EmimCl respectively) were catalysed to glucose and xylose by adding variable amounts of hydrochloric acid (3.5 – 10.5wt%) at temperatures between 100°C to 140°C. Experiments were conducted over 5 hours and in all experiments the monosaccharide concentrations increased to a maximum then decreased as the monosaccharides were degraded to other products. Maximum yields of glucose and xylose of 133mg/g bagasse and 125mg/g bagasse respectively were achieved although under different reaction conditions. The kinetics of the process was modelled as a simple set of first order reactions for the conversion of biomass to sugars then the degradation of sugars to other products.

Sugar production from bioenergy sorghum by using pilot scale continuous hydrothermal pretreatment combined with disk refining

Chemical-free pretreatments are attracting increased interest because they generate less inhibitor in hydrolysates. In this study, pilot-scaled continuous hydrothermal (PCH) pretreatment followed by disk refining was evaluated and compared to laboratory-scale batch hot water (LHW) pretreatment. Bioenergy sorghum bagasse (BSB) was pretreated at 160–190 °C for 10 min with and without subsequent disk milling. Hydrothermal pretreatment and disk milling synergistically improved glucose and xylose release by 10–20% compared to hydrothermal pretreatment alone. Maximum yields of glucose and xylose of 82.55% and 70.78%, respectively were achieved, when BSB was pretreated at 190 °C and 180 °C followed by disk milling. LHW pretreated BSB had 5–15% higher sugar yields compared to PCH for all pretreatment conditions. The surface area improvement was also performed. PCH pretreatment combined with disk milling increased BSB surface area by 31.80–106.93%, which was greater than observed using LHW pretreatment.

Ethanol Production from Sugarcane Bagasse Using Pressurized Microwave Treatment with Inorganic Salts and Salt-Tolerant Yeast

A novel biomass pretreatment method, i.e. pressurized microwave hydrothermal treatment with inorganic salts, and the simultaneous saccharification and fermentation (SSF) using salt-tolerant cellulase, i.e. Meicelase, and salt-tolerant yeast, i.e. Saccharomyces cerevisiae BA11, were studied for the efficient ethanol production from sugarcane bagasse. The component analysis, enzymatic saccharification, and alcohol fermentation were carried out using pressurized microwave treated sugarcane bagasse with various inorganic salts. The pressurized microwave treatment using 2 wt% MgCl2 at a treatment temperature of 200 °C for a treatment time of 5 min followed by SSF without washing treatment of inorganic salts provided the maximum glucose and ethanol yields, i.e. 0.392 and 0.18 g/g-raw material, those corresponded to 99 and 90% of saccharification and ethanol conversion ratios, respectively.

High solid concentrations during the hydrothermal pretreatment of eucalyptus accelerate hemicellulose decomposition and subsequent enzymatic glucose production

To improve the cost and energy efficiencies of glucose production from eucalyptus, we investigated the effect of solid concentration on hemicellulose decomposition during hydrothermal pretreatment, and the subsequent enzymatic production of glucose. The effect of reduced water use during hydrothermal pretreatment prior to enzymatic hydrolysis was examined, which led to relatively concentrated reaction conditions. Pretreatments were conducted at 200 °C with various solid concentrations (9–50 wt%) and severity factors (SF = 4.22 and 4.52). Acetic acid generated through hemicellulose deacetylation increased with increasing solid concentration and SF. Higher levels of acetic acid promoted hemicellulose decomposition during hydrothermal pretreatment through hemicellulose autohydrolysis. The maximum glucose yield following enzymatic hydrolysis was 436.7 mg/g-Eu, which was observed at the highest solid concentration and SF values (50 wt% and 4.52, respectively). We ascribe the observed enhancement to efficient hemicellulose decomposition during pretreatment, which improves enzyme access to the cellulose surface during enzymatic hydrolysis.

Microwave-assisted glucose production from bode (Styrax tonkinensis) woody biomass for bioethanol production

Microwave (MW)-assisted acid hydrolysis of lignocellulosic material derived from bode (Styrax tonkinensis) wood to glucose was performed to find effective uses for discarded chopsticks. The maximum amount of glucose produced by MW-assisted acid hydrolysis (from 1 g of untreated bode wood cellulose) was 0.48 g, and was obtained by heating at 200 °C for 1 min using 1.0% (w/w) sulfuric acid as catalyst. However, the maximum total glucose yield from both MW-assisted acid hydrolysis (0.16 g) and enzymatic hydrolysis of the treated residue (0.52 g) was 0.68 g, which was obtained at a microwave heating temperature of 180 °C for 5 min using 1.0% (w/w) sulfuric acid as catalyst. In conclusion, the results showed that microwave-assisted treatment at 200 °C using 1.0% (w/w) sulfuric acid as catalyst facilitated MW-assisted acid hydrolysis of bode wood cellulose and treatment at 180 °C served as pretreatment for enzymatic hydrolysis of the treated residue.

Intensification of bioethanol production by using Tween 80 to enhance dilute acid pretreatment and enzymatic saccharification of corncob

In second-generation bioethanol production, pretreatment and saccharification have been considered one of the most expensive steps. Thus, we present an approach to improve bioethanol yield by using surfactant concomitantly with corncob pretreatment and saccharification. A response surface methodology (RSM) evaluated the Tween 80 (0%, 5.0%, and 10.0% w/w), in both corncob pretreatment and saccharification, and the enzyme dosage (CellicCTec2: 5.0, 17.5, and 30.0 FPU/gdry matter) on enzymatic digestibility of the acid pretreated biomass. According to the results, higher glucose yields (∼80-85%) could be obtained by reducing the highest enzyme dosage to 41.67% concomitantly by reducing the Tween 80 to 34.2% or 63% by adding it (10% w/w) into only the pretreatment or saccharification, respectively. The RSM suggested applying enzyme dosage between 17.5 and 25.5 FPU/gdry matter associated with the highest Tween 80 amount to improve glucose yield. For statistical validation model, the maximum glucose (80.54%) and xylose (70.66%) yields were obtained for 10.0% of surfactant in both pretreatment and saccharification (25.50 FPU/gdry matter). The hydrolysate was supplemented and fermented by Scheffersomyces stipitis CBS 6054. This yeast fermented the sugars glucose (98.95%), xylose (64.90%), and cellobiose (60.12%) efficiently into ethanol with high yield (0.37 g/g) and volumetric productivity (1.02 gethanol/L.h).

Comparative evaluation of acid and alkaline sulfite pretreatments for enzymatic saccharification of bagasses from three different sugarcane hybrids.

Sugarcane bagasses from three experimental sugarcane hybrids and a mill-reference sample were used to compare the efficiency and mode of action of acid and alkaline sulfite pretreatment processes. Varied chemical loads and reaction temperatures were used to prepare samples with distinguished characteristics regarding xylan and lignin removals, as well as sulfonation levels of residual lignins. The pretreatment with low sulfite loads (5%) under acidic conditions (pH 2) provided maximum glucose yield of 70% during enzymatic hydrolysis with cellulases (10 FPU/g) and β-glucosidases (20 UI/g bagasse). In this case, glucan enzymatic conversion from pretreated materials was mostly associated with extensive xylan removal (70-100%) and partial delignification occurred during the pretreatment. The use of low sulfite loads under acidic conditions required pretreatment temperatures of 160°C. In contrast, at a lower pretreatment temperature (120°C), alkaline sulfite process achieved similar glucan digestibility, but required a higher sulfite load (7.5%). Residual xylans from acid pretreated materials were almost completely hydrolysed by commercial enzymes, contrasting with relatively lower xylan to xylose conversions observed in alkaline pretreated samples. Efficient xylan removal during acid sulfite pretreatment and during enzymatic digestion can be useful to enhance glucan accessibility and digestibility by cellulases. Alkaline sulfite process also provided substrates with high glucan digestibility, mainly associated with delignification and sulfonation of residual lignins. The results demonstrate that temperature, pH, and sulfite can be combined for reducing lignocellulose recalcitrance and achieve similar glucan conversion rates in the alkaline and acid sulfite pretreated bagasses. © 2018 American Institute of Chemical Engineers Biotechnol. Prog., 34:944-951, 2018.

Enzymatic Hydrolysis of Instant Controlled Pressure Drop Pretreated Retama raetam for Bioethanol Production

Since mass diffusion within plant is very weak because of its inappropriate natural structure, Retama raetam biomass was pretreated by thermo-mechanical process “Instant controlled pressure drop” DIC texturing technology prior to submitting it to enzymatic treatment. DIC technology involves subjecting lignocellulosic biomass to saturated steam pressure for a short time followed by a sudden transition from high steam pressure to a vacuum (50 mbar). In this work, an enzymatic hydrolysis was carried out on the DIC pretreated samples by Cellic C-tec2. It was performed according to an experimental design in order to define the best conditions for a maximum glucose recovery. A response surface methodology was used to evaluate the effect of the processing parameters on the released sugar yields. The results showed that the maximum sugars and glucose yields were respectively 50.38 and 36.56 mg/g dry matter obtained at 0.3 M of sulfuric acid, 0.475 MPa of steam pressure for 1 min and four cycles. A minimum formation of undesirable by-products obtained was 0.98 mg/g DB with 0.1 mg/g DB and 0.06 mg/g DB respectively of furfural and HMF.

Sugarcane bagasse as a novel carbon source for heterotrophic cultivation of oleaginous microalga Schizochytrium sp.

Oleaginous microalgae are known as promising oil producers, which accumulate high amount of lipids from various carbon substrates. This study first investigated sugarcane bagasse hydrolysate as a cheap carbon source for the production of biomass and lipid by Schizochytrium sp. The sugarcane bagasse was pretreated with alkali followed by phosphoric acid to remove lignin and enhance xylose production, respectively. The enzymatic hydrolysis of the pretreated sugarcane bagasse by cellulase was subsequently optimized. A maximum glucose yield of 95.77% was obtained at an enzyme loading of 0.3 mL/g with a hydrolysis reaction time of 48 h. The sugarcane bagasse hydrolysate containing glucose and xylose was subsequently used as a substrate for cultivating Schizochytrium sp. Results showed that sugarcane bagasse hydrolysate performed better than refined glucose for cell growth and lipid accumulation. The maximum biomass (10.45 g/L) and lipid content (45.15%) were achieved by growing Schizochytrium sp. in a medium containing 40 g/L glucose in sugarcane bagasse hydrolysate for 72 h. Sugarcane bagasse hydrolysate also resulted in higher levels of polyunsaturated fatty acid and docosahexaenoic acid than did refined glucose. This study suggests that sugarcane bagasse hydrolysate is a low-cost and effective carbon source for microalgal biomass and lipid production.

Technical assessment of natural deep eutectic solvent (NADES) mediated biorefinery process: A case study

Comprehensive evaluation of an integrated process for cellulosic ethanol production from lactic acid+choline chloride+water (LA-CC-H2O) mixture based natural deep eutectic solvent (NADES) pretreated rice straw; solvent recovery and its reusability; extraction of value added products viz., lignin and xylan; enzymatic saccharification and fermentation were studied. Four separate processes viz. pretreatment at 5% (w/v) and 10% (w/v) solids loading and enzymatic hydrolysis at 10% (w/v) and 25% (w/v) solids loading were investigated. No significant difference was observed in holocellulose recovery and lignin solubility in all the tested processes. Hydrolysis at 10% (w/v) and 25% (w/v) solids loading produced maximum glucose yields of 38.6±1.2g/L and 90.3±2.3g/L, respectively. Additional concentration step of sugars is needed from 10% (w/v) hydrolysis for direct ethanol fermentation using Clavispora NRRL Y-50464, while this could be voided with 25% (w/v) hydrolysis sugars. Maximum ethanol yield of 36.7g/L was obtained with 9% (w/v) glucose with a theoretical conversion efficiency of 79.9% which estimated to produce ~129L of ethanol per ton of raw biomass. Alongside, NADES pretreatment resulted in solubilization of 72-75% (w/v) of biomass bound lignin from which 86–90% (w/v) of lignin was recovered. Additionally, >98% (v/v) of the treated NADES reagent was recovered and reused in three consecutive biomass pretreatment cycles with no loss in pretreatment efficiency. This study clearly demonstrated that pretreatment at 10% (w/v) solids loading followed by enzymatic hydrolysis at 25% (w/v) solids loading is the most effective integrated biorefinery process using NADES pretreated rice straw.

Fast Disassembly of Lignocellulosic Biomass to Lignin and Sugars by Molten Salt Hydrate at Low Temperature for Overall Biorefinery.

Lignocellulose is a complex of cellulose, hemicellulose, and lignin, whose overall conversion is still a challenge, especially by a fast and efficient method. Here, a very simple method has been developed using acidic molten salt of zinc chloride hydrate as the solvent and catalyst for complete disassembly of lignocellulose at 95 °C and atmospheric pressure in 12 min. The major products are lignin and monosaccharides, such as glucose and xylose. It was found that high-purity lignin in yield of about 20 wt % can be obtained with various biomass, and the maximum yield of glucose from bamboo is 40.56 wt % and that of xylose from wheat straw is 16.82 wt %. Importantly, zinc chloride can be recovered through precipitation by ammonia and reused for next cycles. It provides a simple route to separate and efficiently convert lignocellulose, especially high-grade feedstock for biorefinery.

Sulfonated biochar as acid catalyst for sugar hydrolysis and dehydration

This study investigated the use of 30 w/v% H2SO4 sulfonated wood waste-derived biochar as catalysts for production of value-added chemicals from carbohydrates in water as an environmentally benign solvent. Physicochemical characteristics of the sulfonated biochar were revealed by Fourier transform infrared spectroscopy (FTIR), acid-base neutralization titration, gas adsorption analysis, thermogravimetric analysis (TGA), and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX). Using the sulfonated biochar as catalysts, hydrolysis of maltose at 140–160 °C resulted in the maximum glucose yield of 85.4% and selectivity of 88.2%, whereas dehydration of fructose at 160–180 °C produced the maximum HMF yield of 42.3% and selectivity of 60.4%. A higher range of reaction temperature was required for fructose dehydration due to the higher energy barrier compared to maltose hydrolysis. While increasing the temperature accelerated the catalytic reactions, the maximum product selectivity remained unchanged in the sulfonated biochar-catalyzed systems. The products were stable despite the increase in reaction time, because rehydration and adsorption of products was found to be minor although polymerization of intermediates led to unavoidable carbon loss. This study highlights the efficacy of engineered biochars in biorefinery as an emerging application.

Assisted of electromagnetic fields in glucose production from cassava stems

Decrease in fossil fuel reserves that led to high price has become major problem in many countries around the world. To acquire the sustainability of energy reserves, the renewable energies obtained from plant biomass will therefore have to play an increasing role in fulfilling energy demand throughout the century. Renewable energy source must be explored by innovative techniques which is safe to the environment and low in energy consumptions. This research conducted to produce glucose from cassava stems assisted by electromagnetic field inductions process. The parameters used in this research were pretreatment solvent, concentration, temperature and electrical currents. The electromagnetic field inductions could be applied to increase glucose productivity with the maximum yield of glucose was 47.43%.

Combined effect of inorganic salts with calcium peroxide pretreatment for kenaf core biomass and their utilization for 2,3-butanediol production

This study focuses on development of calcium peroxide (CaO2) pretreatment that removes major part of lignin but retaining most of sugar components of kenaf core powder (KCP) biomass. In chemical pretreatment, usually higher loss of biomass occurs which was less during this pretreatment strategy. Supplementation of inorganic salts; manganese sulfate (MnSO4) and cobalt chloride (COCl2) in CaO2 pretreatment resulted in maximum delignification of KCP relative to individual CaO2 pretreatment. Maximum glucose yield (98%) and hydrolysis yield (80.5%) was achieved after enzymatic hydrolysis (30 FPU/g of KCP) under optimized conditions. Analytical results proved effective lignin removal and significant destruction of KCP with this pretreatment strategy. Finally, utilization of KCP enzymatic hydrolysates by developed strain Klebsiella pneumoniae KMK05 resulted in maximum 2,3-butanediol (BDO) production (10.42 g/L) and BDO titer (0.385 g/g of sugar). BDO titer achieved with KCP derived sugars were found comparable with the mixture of standard sugars which is notable.

Delignification and Hydrolysis Lignocellulosic of Bagasse in Choline Chloride System

Bagasse was the waste which has a fairly high content of lignocelluloses and has not been utilize optimally. With a cellulose content of up to 40%, bagasse then potentially be used as raw material for bioethanol. In this research, delignification process was carried out using sodium hydroxide (NaOH) in the ionic liquid system and without ionic liquids. The purpose of this research was to find out the highest content of cellulose which contained in the bagasse and the best hydrolysis conditions was obtained at the hydrolysis process in the choline chloride (ChCl) system. The hydrolysis stage in this research was carried out at temperature 105 °C, catalyst (H2SO4) 10% (w/w) cellulose, ChCl 10%, 15%, and 20% (w/w) cellulose and it was stirred at constant speed 120 rpm with reaction time of 30, 60 and 90 minutes. Delignification research results used ChCl obtained highest content of cellulose was 39.8%, hemicellulose 18.59%, and lignin 3.62% in cooking treatment 90 minutes and 20% ChCl. While delignification without ChCl obtained highest content of cellulose is 24.98%, hemicellulose 8.25%, and lignin 18.99% in cooking treatment 90 minutes. The maximum glucose yield of 39.4% was obtained at reaction time 90 minutes and 15% of ChCl.

Cellulose Accessibility and Zeta potentials of Sugarcane Bagasse Pretreated by Green Liquor and Ethanol for High Hydrolysis Efficiency

Green liquor (GL) combined with ethanol (GL-ethanol) was selected to pretreat sugarcane bagasse (SCB). The results showed that the maximum lignin removal of 85.2% was achieved at 160 °C and a GL loading of 1.5 mL/g-dry substrate. The glucose yield of pretreated SCB increased with increased pretreatment temperature, and the maximum glucose yield of 97.7% was reached from SCB pretreated at 160 °C. Simons’ stain (SS) showed that the glucose yield was affected by cellulose accessibility instead of lignin content when lignin removal was > 70%. The cellulase adsorption isotherm fitted by the Langmuir model showed that the strength of interaction between the cellulase and substrate of GL-ethanol-100/1.5 (100 °C, 1.5 mL GL/g-dry substrate) was declining with increased pH. The adsorption was pH-dependent, and negatively controlled by the pH value. Electrostatic interactions can account for the pH-dependency of cellulase adsorption.

Chemical Pretreatment-Independent Saccharifications of Xylan and Cellulose of Rice Straw by Bacterial Weak Lignin-Binding Xylanolytic and Cellulolytic Enzymes.

Complete utilization of carbohydrate fractions is one of the prerequisites for obtaining economically favorable lignocellulosic biomass conversion. This study shows that xylan in untreated rice straw was saccharified to xylose in one step without chemical pretreatment, yielding 58.2% of the theoretically maximum value by Paenibacillus curdlanolyticus B-6 PcAxy43A, a weak lignin-binding trifunctional xylanolytic enzyme, endoxylanase/β-xylosidase/arabinoxylan arabinofuranohydrolase. Moreover, xylose yield from untreated rice straw was enhanced to 78.9% by adding endoxylanases PcXyn10C and PcXyn11A from the same bacterium, resulting in improvement of cellulose accessibility to cellulolytic enzyme. After autoclaving the xylanolytic enzyme-treated rice straw, it was subjected to subsequent saccharification by a combination of the Clostridium thermocellum endoglucanase CtCel9R and Thermoanaerobacter brockii β-glucosidase TbCglT, yielding 88.5% of the maximum glucose yield, which was higher than the glucose yield obtained from ammonia-treated rice straw saccharification (59.6%). Moreover, this work presents a new environment-friendly xylanolytic enzyme pretreatment for beneficial hydrolysis of xylan in various agricultural residues, such as rice straw and corn hull. It not only could improve cellulose saccharification but also produced xylose, leading to an improvement of the overall fermentable sugar yields without chemical pretreatment.IMPORTANCE Ongoing research is focused on improving "green" pretreatment technologies in order to reduce energy demands and environmental impact and to develop an economically feasible biorefinery. The present study showed that PcAxy43A, a weak lignin-binding trifunctional xylanolytic enzyme, endoxylanase/β-xylosidase/arabinoxylan arabinofuranohydrolase from P. curdlanolyticus B-6, was capable of conversion of xylan in lignocellulosic biomass such as untreated rice straw to xylose in one step without chemical pretreatment. It demonstrates efficient synergism with endoxylanases PcXyn10C and PcXyn11A to depolymerize xylan in untreated rice straw and enhanced the xylose production and improved cellulose hydrolysis. Therefore, it can be considered an enzymatic pretreatment. Furthermore, the studies here show that glucose yield released from steam- and xylanolytic enzyme-treated rice straw by the combination of CtCel9R and TbCglT was higher than the glucose yield obtained from ammonia-treated rice straw saccharification. This work presents a novel environment-friendly xylanolytic enzyme pretreatment not only as a green pretreatment but also as an economically feasible biorefinery method.