Cellulase Concentration Research Articles

Enzymatic degumming of pineapple (Ananas comosus) mill juice using crude and commercial enzymes

In present study, the pineapple (Ananas comosus) mill juice was treated with crude and commercial enzyme for the degumming of the mill juice to improve its quality in terms of filtration rate, clarity, relative viscosity and percentage overrun. Response surface methodology was used to investigate the effects of concentration of cellulase (25–125 mg/100 ml), pectinase (25–150 mg/100 ml), hemicellulase (25–150 mg/100 ml), time (210–540 min) and temperature (35–55 °C) on filtration rate, clarity, relative viscosity and percentage overrun of the pineapple mill juice. The recommended enzymatic treatment conditions from the study were: concentration of cellulase 124 mg/100 ml, concentration of pectinase 141 mg/100 ml, concentration of hemicellulase 78 mg/100 ml, time 455 min and temperature 46 °C. The crude enzyme treatment of the mill juice samples under the same conditions of time and temperature was also carried out. Principal component analysis was applied to look at the difference between crude and commercial enzyme treated samples. The data revealed that the crude enzyme was competitive to the commercial enzymes for the degumming of the pineapple mill juice.

Enzymatic hydrolysis of steam-pretreated sweet sorghum bagasse by combinations of cellulase and endo-xylanase

Abstract Sweet sorghum bagasse (SSB) is considered a potential lignocellulosic raw material for the production of fuel ethanol by means of pretreatment, enzymatic hydrolysis and fermentation. Enzyme cocktail composition is critical to achieve maximum sugar yield per gram of enzyme used. Given that the enzyme composition relies on feedstock properties and pretreatment applied, the main objective of this study was to develop an optimised combination of cellulase (Cellic® CTec2) and endo-xylanase (Cellic® HTec2) enzyme preparations (cocktail) that is adapted to steam treated sorghum bagasse. This was done by using a central composite design by which combined effects of Cellic® CTec2 and Cellic® HTec2 were investigated further using response surface methodology (RSM). The optimum was defined as the minimum total enzyme dosage that is needed for a target glucan conversion of at least 80% for an incubation period of 72 h. The addition of Cellic® HTec2 proved to boost the glucan conversion to glucose by Cellic® CTec2, but synergistic interaction was only observed at early stages of the enzymatic hydrolysis and mainly for those combinations with lower cellulase content. The pretreatment and enzymatic hydrolysis with 0.15 mL/g WIS (water insoluble solids) of Cellic® CTec2 (24.9 mg protein/g WIS) and 0.32 mL/g WIS of Cellic® HTec2 (54 mg protein/g WIS), respectively, resulted in 364.8 kg sugar/ton of bagasse, 20% more than with a conventional enzyme combination.

Design and optimization of a sono-hybrid process for bioethanol production from Parthenium hysterophorus

This paper presents a laboratory scale process for production of bioethanol from Parthenium hysterophorus. This process consists of three steps, viz. biomass pretreatment, enzymatic hydrolysis of pretreated biomass and fermentation of pentose and hexose hydrolyzates obtained from acid pretreatment and enzyme hydrolysis, respectively. The step of enzyme hydrolysis has been optimized using response surface methodology for concentrations of the enzymes and the concentration of biomass. The optimum parameters were: biomass concentration = 4.212% (w/v), cellulase concentration = 135.86 FPU/g substrate and cellobiase concentration = 75 U/g substrate. Use of ultrasound during enzymatic hydrolysis at optimized conditions resulted in a marked 18-fold enhancement in the kinetics of hydrolysis. Fermentation of the pentose hydrolyzate with Candida shehatae NCIM 3500 resulted to ethanol yield of 0.069 g/g raw biomass, while fermentation of the enzymatic hydrolyzate with Saccharomyces cerevisiae MTCC 170 resulted to an ethanol yield of 0.187 g/g raw biomass. The total ethanol yield from fermentation of pentose and hexose hydrolyzates was 0.26 g/g raw biomass. This process also provides a potential solution to effective utilization of the noxious waste biomass of P. hysterophorus.

Optimization of enzymatic saccharification of water hyacinth biomass for bio-ethanol: Comparison between artificial neural network and response surface methodology

Response surface methodology (RSM) is commonly used for optimising process parameters affecting enzymatic hydrolysis. However, artificial neural network–genetic algorithm hybrid model can also serve as an effective option, primarily for non-linear polynomial systems. The present study compares these approaches for enzymatic hydrolysis of water hyacinth biomass to maximise total reducing sugar (TRS) for bio-ethanol production. Maximum TRS (0.5672g/g) was obtained using 9.92 (% w/w) substrate concentrations, 49.56 U/g cellulase concentrations, 280.33 U/g xylanase concentrations and 0.13 (% w/w) surfactant concentrations. The average % error for artificial neural networking (ANN) and RSM were 3.08 and 4.82 and the prediction percentage errors in optimum output are 0.95 and 1.41, respectively, which showed the supremacy of ANN in illustrating the non-linear behaviour of the system. Fermentation of the hydrolysate yielded a maximum ethanol concentration of 10.44g/l using Pichia stipitis, followed by 8.24 and 6.76g/l for Candida shehatae and Saccharomyces cerevisiae.

High-titer lactic acid production from NaOH-pretreated corn stover by Bacillus coagulans LA204 using fed-batch simultaneous saccharification and fermentation under non-sterile condition

Lactic acid (LA) is an important chemical with various industrial applications. Non-food feedstock is commercially attractive for use in LA production; however, efficient LA fermentation from lignocellulosic biomass resulting in both high yield and titer faces technical obstacles. In this study, the thermophilic bacterium Bacillus coagulans LA204 demonstrated considerable ability to ferment glucose, xylose, and cellobiose to LA. Importantly, LA204 produces LA from several NaOH-pretreated agro stovers, with remarkably high yields through simultaneous saccharification and fermentation (SSF). A fed-batch SSF process conducted at 50°C and pH 6.0, using a cellulase concentration of 30FPU (filter paper unit)/g stover and 10g/L yeast extract in a 5-L bioreactor, was developed to produce LA from 14.4% (w/w) NaOH-pretreated non-sterile corn stover. LA titer, yield, and average productivity reached 97.59g/L, 0.68g/g stover, and 1.63g/L/h, respectively. This study presents a feasible process for lignocellulosic LA production from abundant agro stovers.

Optimization of Cellulase ProducingAspergillus flavusSB4 by Solid State Fermentation using Response Surface Methodology (RSM)-CCD

Solid State fermentation is widely applied to produce many enzymes and metabolites mainly from fungi. Multiple substrate (Paddy straw, Sugarcane bagasse, Rice husk and wheat bran) were mixed in different combination. Aspergillus flavus isolated from rhizosphere was inoculated. After incubation, the cellulase concentration was quantified using FPase. The optimum parameter for the production of cellulase was analysed using RSM –CCD. The results were evaluated on 28th day of incubation. R2 value was 0.989, adjusted R2 was 0.9788 and predicted R2 is 0.9505. The quadratic model gave a satisfactory description of the experimental data. Under optimum conditions, a maximum cellulase concentration of 55.43 IU/g was predicted according to the developed model.

Effects of nitrate and fumarate in tree leaves-based diets on nutrient utilization, rumen fermentation, microbial protein supply and blood profiles in sheep

This experiment was conducted to study the effects of nitrate and fumarate on nutrient utilization, rumen fermentation and blood biochemical profile in sheep fed on tree leaves-based diet. Thirty two matured male Chokla breed of sheep (2–3 years old and 46.9±0.95kg average body weight) were equally distributed in a randomized block design in four groups with similar average age and mean body weight. All groups were fed diets containing roughage and concentrate in a 70:30 ratio. Control group (C) was fed with cenchrus (Cenchrus ciliaris) straw as an only roughage source, whereas other three groups (T1, T2 and T3) were fed with cenchrus straw, ardu (Ailanthus excelsa) leaves and khejri (Prosopis cineraria) leaves (50:25:25) as roughage sources. Animals in the T1 group were not supplemented with any feed additive; whereas, animals in the T2 and T3 groups were added with 2% potassium nitrate of the concentrate mixture and 2% fumarate of the dry matter (DM) intake, respectively. There were no effects (P>0.10) of any treatments on DM intake, BW change or nutrient utilization. N retention increased in treatment groups compared with control due to greater amount of N intake. Concentrations of glucose, haemoglobin, albumin, blood urea nitrogen and creatinine, and different blood enzyme concentrations were not affected (P>0.10) by any treatments, but concentrations of total protein, globulin and cholesterol in blood were higher for T1 and T3 than for C and T2 treatments. Microbial N supply in terms of digestible OM intake or digestible OM retained in the rumen did not differ among treatments. Total amylase and carboxymethyl cellulase concentrations were similar among the groups. However, total xylanase activity increased in T3 group than other groups. A reduction in average propionate concentration (P=0.020) was observed for the T2 treatment in comparison with the C and T1 groups. Concentrations of ammonia N, total N and trichloroacetate-perceptible N were lower in control than other treatments, but concentrations of soluble N were not affected (P>0.05) by any treatments. In conclusion, fumarate (2% of DM) may be included in the diet of sheep fed with ardu–khejri leaves without affecting nutrient utilization and rumen fermentation, whereas ardu–khejri leaves diet containing nitrate (0.6% of DM) may affect rumen fermentation.

Lignin triggers irreversible cellulase loss during pretreated lignocellulosic biomass saccharification.

BackgroundNon-productive binding of enzymes to lignin is thought to impede the saccharification efficiency of pretreated lignocellulosic biomass to fermentable sugars. Due to a lack of suitable analytical techniques that track binding of individual enzymes within complex protein mixtures and the difficulty in distinguishing the contribution of productive (binding to specific glycans) versus non-productive (binding to lignin) binding of cellulases to lignocellulose, there is currently a poor understanding of individual enzyme adsorption to lignin during the time course of pretreated biomass saccharification.ResultsIn this study, we have utilized an FPLC (fast protein liquid chromatography)-based methodology to quantify free Trichoderma reesei cellulases (namely CBH I, CBH II, and EG I) concentration within a complex hydrolyzate mixture during the varying time course of biomass saccharification. Three pretreated corn stover (CS) samples were included in this study: Ammonia Fiber Expansiona (AFEX™-CS), dilute acid (DA-CS), and ionic liquid (IL-CS) pretreatments. The relative fraction of bound individual cellulases varied depending not only on the pretreated biomass type (and lignin abundance) but also on the type of cellulase. Acid pretreated biomass had the highest levels of non-recoverable cellulases, while ionic liquid pretreated biomass had the highest overall cellulase recovery. CBH II has the lowest thermal stability among the three T. reesei cellulases tested. By preparing recombinant family 1 carbohydrate binding module (CBM) fusion proteins, we have shown that family 1 CBMs are highly implicated in the non-productive binding of full-length T. reesei cellulases to lignin.ConclusionsOur findings aid in further understanding the complex mechanisms of non-productive binding of cellulases to pretreated lignocellulosic biomass. Developing optimized pretreatment processes with reduced or modified lignin content to minimize non-productive enzyme binding or engineering pretreatment-specific, low-lignin binding cellulases will improve enzyme specific activity, facilitate enzyme recycling, and thereby permit production of cheaper biofuels.

Increase in stability of cellulase immobilized on functionalized magnetic nanospheres

Abstract Functionalized magnetic nanospheres were prepared by co-condensation of tetraethylorthosilicate with three different amino-silanes: 3-(2-aminoethylamino propyl)-triethoxysilane (AEAPTES), 3-(2-aminoethylamino propyl)-trimethoxysilane (AEAPTMES) and 3-aminopropyltriethoxysilane (APTES). Then three functionalized magnetic nanospheres were used as supports for immobilization of cellulase. The three functionalized magnetic nanospheres with core–shell morphologies exhibited higher capacity for cellulase immobilization than unfunctionalized magnetic nanospheres. The increasing of surface charge of functionalized magnetic nanospheres leads to an enhancement of the capacity of cellulase immobilization. Particularly, AEAPTMES with methoxy groups was favored to be hydrolyzed and grafted on unfunctionalized magnetic nanospheres than the others. AEAPTMES functionalized magnetic nanospheres with the highest zeta potential (29 mV) exhibited 87% activity recovery and the maximum amount of immobilized cellulase was 112 mg/g support at concentration of initial cellulase of 8 mg/mL. Immobilized cellulase on AEAPTMES functionalized magnetic nanospheres had higher temperature stability and broader pH stability than other immobilized cellulases and free cellulase. In particular, it can be used in about 40 °C, demonstrating the potential of biofuel production using this immobilized cellulase.

Study on the Saccharification Conditions of Fuel Ethanol from Corn Straw

To study the saccharification conditions of cellulase on lignocellulose material, this paper used corn straw as the material to do research on the effect of cellulase. The hydrolysis factors, including reaction temperature, reaction time and cellulase concentration, were measured in order to determine the optimal saccharification conditions for fuel ethanol production. The results showed that, when the reaction temperature was 45°C, reaction time was 72 h and cellulase concentration was 60 IU/g, the hydrolysis rate can respectively reach 6.25 %, 14.7 % and 14.4 %. By the analysis of orthogonal test, the main factors effects the saccharification was reaction time. And the optimal combination of saccharification conditions was the reaction time of 54 h, the reaction temperature of 45 °C, and the cellulase concentration of 55 IU/g.

Combined effect of ultrasound and enzymatic pretreatment on yield and functional properties of taro (Colocasia esculenta) starch

A combined effect of ultrasound and enzymatic pretreatment on yield and functional properties of taro starch was investigated. A 3 × 2 × 2 factorial design was employed with three factors, i.e., sonication time (0, 10, and 20 min), concentration of cellulase (0 and 100 U/100 g fresh tuber) and xylanase (0 and 100 U/100 g fresh tuber). Starch yield varied from 14.60 to 20.81%. The highest yield of 20.81% was obtained, when ultrasonication time was 20 min and concentration for both cellulase and xylanase was 100 U/100 g taro tubers, which was an increase of 42.53% from conventional method. An increase in swelling, solubility and pasting properties of the isolated starches pretreated only with ultrasound was observed, but no such difference was observed with enzymes alone, or when ultrasound was applied in combination with enzymes. A slight decrease in clarity of the starch pastes was also observed after ultrasonication. Freeze‐thaw stability of the starches was found to be better when ultrasound was used as pretreatment for extraction. Higher yield of starch with better functional properties can be achieved from taro tubers by using combination of ultrasound and enzymes.

Optimization of starch isolation from taro using combination of enzymes and comparison of properties of starches isolated by enzymatic and conventional methods.

The optimization of enzymatic starch isolation process from taro tubers using cellulase and xylanase was carried out. The functional properties of starch isolated by optimized enzymatic process were compared with starch isolated by conventional method without the use of enzymes. A central composite rotatable design (CCRD) with four numerical factors was employed to design the experiments. The numerical factors were cellulase concentration (0-100 U/100g tuber), xylanase concentration (0-100 U/100g tuber), temperature of incubation (30-50°C) and incubation time (1-5h). Statistical analysis showed that the main effects of all the factors were significant on starch yield and effect of cellulase was more significant compared to xylanase. The effectiveness of xylanase in increasing the yield of starch from taro tubers confirmed that xylan is an important component of the cell walls of taro tubers. The optimized condition with maximum starch yield (17.22%) was obtained when cellulase and xylanase concentration were 299.86 and 300 U/100g tuber, temperature was 35°C and incubation time was 2h. The swelling of the starch granules increased whereas solubility decreased for enzymatic method. The clarity of the starch paste isolated by enzymatic method was found to be better compared to the clarity of starch paste isolated by conventional method. The pasting temperature of the starch paste was slightly higher and viscosity was lower for the starch isolated by enzymatic method. Freeze-thaw stability of the starch paste was also found to be better for the enzymatically isolated starch.

Ethanol production from sunflower meal biomass by simultaneous saccharification and fermentation (SSF) with Kluyveromyces marxianus ATCC 36907.

The lignocellulosic materials are considered promising renewable resources for ethanol production, but improvements in the processes should be studied to reduce operating costs. Thus, the appropriate enzyme loading for cellulose saccharification is critical for process economics. This study aimed at evaluating the concentration of cellulase and β-glucosidase in the production of bioethanol by simultaneous saccharification and fermentation (SSF) of sunflower meal biomass. The sunflower biomass was pretreated with 6% H2SO4 (w/v), at 121 °C, for 20 min, for hemicellulose removal and delignificated with 1% NaOH. SSF was performed with Kluyveromyces marxianus ATCC 36907, at 38 °C, 150 rpm, for 72 h, with different enzyme concentrations (Cellulase Complex NS22086-10, 15 and 20 FPU/gsubstrate and β-Glucosidase NS22118, with a cellulase to β-glucosidase ratio of 1.5:1; 2:1 and 3:1). The best condition for ethanol production was cellulase 20 FPU/gsubstrate and β-glucosidase 13.3 CBU/gsubstrate, resulting in 27.88 g/L ethanol, yield of 0.47 g/g and productivity of 0.38 g/L h. Under this condition the highest enzymatic conversion of cellulose to glucose was attained (87.06%).

Enzymolysis-ultrasonic assisted extraction, chemical characteristics and bioactivities of polysaccharides from corn silk

An enzymolysis-ultrasonic assisted extraction (EUAE) procedure of corn silk polysaccharides (CSPS) was established and the physicochemical properties, antioxidant and anticancer activities of CSPS were studied. Orthogonal test and response surface methodology were applied to optimize the extraction parameters. The optimum enzymolysis and ultrasonic conditions were cellulase content of 7.5% for 150min at 55°C and liquid–solid ratio of 31.8 for 34.2min at 66.3°C, respectively. Under these conditions, the yield of CSPS increased from 4.56% to 7.10%. CSPS obtained by hot water and EUAE were composed of rhamnose, arabinose, xylose, mannose, galactose and glucose with molecular ratios of 4.17:17.33:5.59:18.65:19.11:35.14 and 8.83:15.77:7.92:12.39:11.15:43.94, respectively. Their molecular weight distributions were 10.52×104 and 6.88×104Da, respectively. CSPS obtained by EUAE showed morphological and conformation changes and higher antioxidant and anticancer activities compared with CSPS extracted by hot water.

Inclusion of different exogenous fibrolytic enzymes to dry jowar fodder and their effect on in vitro total gas production

Aim: Our objective was to estimate in-vitro gas production from dry jowar fodder added with different concentrations of exogenous fibrolytic enzymes (EFEs) like neutral cellulase and fungal xylanase. Materials and Methods: 34 different samples of dry jowar fodder were prepared according to different concentrations of neutral cellulase, fungal xylanase and neutral cellulase + fungal xylanase (1:1). Sample not containing any enzymes was considered as the control group. These 34 samples were subjected to further in vitro gas production analysis. Results: Statistically, significantly higher (P<0.05) potential gas production was recorded for 0.7 % at 6 hr period, 0.7 % at 12 hr period, 0.7 %, 0.8 % at 18 hr period and 0.7 %, 0.8 % at 24 hr period in the samples treated with neutral cellulase. Significantly higher potential gas production was recorded for 0.5 %, 0.8 % at 6 hr period, 0.5 %, 0.6 %, 0.8 % at 12 hr period, 0.8 % at 18 hr period and 0.5 %, 0.6 %, 0.8 % at 24 hr period in the samples treated with fungal xylanase. Significantly higher potential gas production was recorded for 0.6 %, 0.6 %, 0.8 % at 6 hr period, 0.6 %, 0.8 % at 12 hr period, 0.6 %, 0.8 % at 18 hr period and 0.6 %, 0.8 % at 24 hr period in the samples treated with mixture of neutral cellulase + fungal xylanase (1:1).

Adsorption and Hydrolytic Activity of the Polycatalytic Cellulase Nanocomplex on Cellulose

The formation of polycatalytic enzyme complexes may enhance the effectiveness of enzymes due to improved substrate interaction and synergistic actions of multiple enzymes in proximity. Much effort has been made to develop highly efficient polycatalytic cellulase complexes by immobilizing cellulases on low-cost polymer or nanoparticle scaffolds, aiming at their potential applications in biomass conversion to fuels. However, some key cellulases carry out the hydrolytic reaction on crystalline cellulose in a directional, processive manner. A large, artificial polycatalytic complex is unlikely to undergo a highly coordinated motion to slide on the cellulose surface as a whole unit. The mechanism underlying the activity enhancements observed in some artificial cellulase complexes and the limit of this approach remain elusive. Herein, we report the synthesis of polycatalytic cellulase complexes bound to colloidal polymer nanoparticles with a magnetic core and describe their unique adsorption, hydrolytic activities, and motions on cellulose. The polycatalytic clusters of cellulases on colloidal polymers show an increased rate of hydrolytic reactions on cellulose, but this was observed mainly at relatively low cellulase-to-cellulose ratios. Enhanced efficiency is mainly attributed to increased local concentrations of cellulases on the scaffolds and their polyvalent interactions with cellulose. However, once bound, the polycatalytic complexes can only carry out reactions locally and are not capable of relocating to new sites rapidly due to their lack of long-range surface mobility and their extremely tight binding. The development of highly optimized polycatalytic complexes may arise by developing novel nanoscaffolds that induce concerted motion of the complex as a whole.

A novel non-hydrolytic protein from Pseudomonas oryzihabitans enhances the enzymatic hydrolysis of cellulose

Several kinds of protein such as the expansin, expansin-like proteins and LPMOs (lytic polysaccharide monooxygenases) are known to exert enhancement effects on cellulase activity. In this study, a novel cellulase synergistic protein named POEP1 was purified from the culture filtrate of Pseudomonas oryzihabitans CGMCC 6169, and was homogeneous on SDS-PAGE with a molecular weight of 60kDa. Mass spectrometry analysis indicated that it was an unknown protein without sequence similarity to the expansin and expansin-like proteins. Evaluation of the enzymatic hydrolysis of filter paper revealed that POEP1 had no cellulase activity but displayed high synergistic activity of 364% at a cellulase concentration of 0.1FPU/g of filter paper. When a mixture containing 0.6FPU cellulase and 700μg POEP1 per g of cellulose was evaluated, the maximal sugar yield was achieved, which was 2.2-fold greater than that with the cellulase alone. POEP1 was found to have functional similarity to the expansin and expansin-like proteins, which could decrease both the hydrogen-bond intensity and crystallinity, and cause the filter paper disruption. This study provided evidence for the existence of novel bacterial proteins in nature serving the same function as expansin and expansin-like proteins.

Enzymatic hydrolysis, adsorption, and recycling during hydrolysis of bagasse sulfite pulp

The high costs of enzymatic hydrolysis along with the high enzyme dosage are often considered as the major bottlenecks in lignocellulosic bioconversion. This study investigated the hydrolysis efficiency, cellulase adsorption and enzyme recycling during the hydrolysis of bagasse sulfite pulp (BSP). After 48 h of hydrolysis, more than 70% of the cellulose was hydrolyzed, while the protein concentration and cellulase activity in solution remained 31% and 17% of the initial value, respectively. The cellulase adsorption on the fresh BSP was better fitted by a Sips model, suggesting the occurrence of a multilayer adsorption at low cellulase concentration and monolayer adsorption at high concentration on the BSP surfaces. Desorption profile studies showed that the optimum desorption condition was at pH 4.8 and 40 °C. Moreover, considering the limited ability to desorption, directly empolying the bound enzyme with residual substrate is more effective method to recover cellulase during the hydrolysis of BSP.

Development of appropriate fibrolytic enzyme combination for maize stover and its effect on rumen fermentation in sheep.

In vitro studies were undertaken to develop an appropriate fibrolytic enzymes cocktail comprising of cellulase, xylanase and β-D-glucanase for maize stover with an aim to increase its nutrient utilization in sheep. Cellulase and xylanase added individually to ground maize stover at an increasing dose rates (0, 100, 200, 400, 800, 1,600, 3,200, 6,400, 12,800, 25,600, 32,000, 38,400, and 44,800 IU/g DM), increased (p<0.01) the in vitro dry matter digestibility and in vitro sugar release. The doses selected for studying the combination effect of enzymes were 6,400 to 32,000 IU/g of cellulase and 12,800 to 44,800 IU/g of xylanase. At cellulase concentration of 6,400 IU/g, IVDMD % was higher (p<0.01) at higher xylanase doses (25,600 to 44,800 IU/g). While at cellulase doses (12,800 to 32,000 IU/g), IVDMD % was higher at lower xylanase doses (12,800 and 25,600 IU/g) compared to higher xylanase doses (32,000 to 44,800 IU/g). At cellulase concentration of the 6,400 to 32,000 IU/g, the amount of sugar released increased (p<0.01) with increasing levels of xylanase concentrations except for the concentration of 44,800 IU/g. No effect of β-D-glucanase (100 to 300 IU/g) was observed at lower cellulase-xylanase dose (cellulase-xylanase 12,800 to 12,800 IU/g). Based on the IVDMD, the enzyme combination cellulase-xylanase 12,800 to 12,800 IU/g was selected to study its effect on feed intake and rumen fermentation pattern, conducted on 12 rams (6 to 8 months; 20.34±2.369 kg body weight) fed 50% maize stover based TMR. The total volatile fatty acids (p<0.01) and ammonia-N concentration was higher in enzyme supplemented group, while no effect was observed on dry matter intake, ruminal pH and total nitrogen concentration.

Crude Cellulase from Oil Palm Empty Fruit Bunch by Trichoderma asperellum UPM1 and Aspergillus fumigatus UPM2 for Fermentable Sugars Production

Cellulase is an enzyme that converts the polymer structure of polysaccharides into fermentable sugars. The high market demand for this enzyme together with the variety of applications in the industry has brought the research on cellulase into focus. In this study, crude cellulase was produced from oil palm empty fruit bunch (OPEFB) pretreated with 2% NaOH with autoclave, which was composed of 59.7% cellulose, 21.6% hemicellulose, and 12.3% lignin using Trichoderma asperellum UPM1 and Aspergillus fumigatus UPM2. Approximately 0.8 U/ml of FPase, 24.7 U/ml of CMCase and 5.0 U/ml of β-glucosidase were produced by T. asperellum UPM1 at a temperature of 35 °C and at an initial pH of 7.0. A 1.7 U/ml of FPase, 24.2 U/ml of CMCase, and 1.1 U/ml of β-glucosidase were produced by A. fumigatus UPM2 at a temperature of 45 °C and at initial pH of 6.0. The crude cellulase was best produced at 1% of substrate concentration for both T. asperellum UPM1 and A. fumigatus UPM2. The hydrolysis percentage of pretreated OPEFB using 5% of crude cellulase concentration from T. asperellum UPM1 and A. fumigatus UPM2 were 3.33% and 19.11%, with the reducing sugars concentration of 1.47 and 8.63 g/l, respectively.