Papers by Keyword: Cellulase

Abstract: Immobilized enzymes have higher resistance to environmental changes and can be easily obtained/re-recovered/reusable compared with their free form after use in the biocatalysis process. The main benefit of immobilization is that it protects the enzyme from harsh environmental conditions (e.g. high temperatures, extreme pH values, etc.). However, the enzyme immobilization process is not easy and cheap. Most cellulases used in Indonesia are single-use enzymes and are unstable. This causes the use of cellulase on an industrial scale to be expensive and difficult to store for a long time. Therefore, a solution is needed to mobilize cellulase with a simple and inexpensive process, namely by utilizing activated carbon from the shell of a Calophyllum inophyllum seed. This study aimed to investigate the potential of activated carbon made from C. inophyllum shell as an immobilizer for the production of cellulase. An optimal, easy, and simple enzyme immobilization method is required to ensure sufficient cellulase quality and quantity for industrial scale. In general, the four stages of research were as follows: a) the synthesis of activated carbon made from C. inophyllum shell; b) cellular immobilization synthesis; c) stability test of immobilized cellulase against pH and temperature; and d) reusability analysis of immobilized enzymes. This study examined the effect of carbon particle size (60 and 100 mesh) and concentration of ZnCl₂ activator (1, 2, and 3 M). The results indicate that the optimal manufacturing of C. inophyllum shell activated carbon is by using a size of 100 Mesh with a concentration of ZnCl₂ activator of 2 M, which has an enzyme activity in the range of ±0.25 units/mL, and the immobilized cellulase remains effective for up to 5 reuse cycles.

Abstract: Pineapple wastes (skin, core and crown) are mainly composed of carbohydrates (cellulose, hemicellulose, and lignin). Non-starch polysaccharides (NSP) in feed are indigestible by the endogenous enzymes in poultry. Thus, exogenous enzymes (xylanase and cellulase) are required to overcome this problem. Due to high fiber content, pineapple wastes are unsuitable for animal feed. However, the fermented waste juice could be used to produce enzymes. The objective of this study is to produce xylanase and cellulase from the fermentation of pineapple waste using Lactobacillus casei (L. casei) bacteria inoculated from probiotic drink. The fermentation was performed using different screening parameters (incubation time, temperature, pH value and substrate concentration) according to Two-Level Full Factorial Design (FFD) by Design Expert. From this study, the incubation temperature and substrate concentration had the highest influence on the xylanase activity (39.82 U/mL) while the fermentation time and substrate concentration mostly affected the cellulase activity (8.05 U/mL). Meanwhile, the pH had the least influence on both enzyme activities. The pineapple waste at its best fermentation parameters not only offers an economical way of high enzyme production but also alleviates the agricultural waste disposal issue. Further optimization of the pineapple waste fermentation parameters is required though to maximize enzyme production.

Abstract: Coffee pulp biomass waste can easily be found anywhere in Indonesia, considering it is the fourth world's largest coffee exporter. The utilization of coffee pulp is very limited and is categorized as a source of pollutants in water bodies and soils. In contrast, coffee pulp waste is very potential because 63% of the main compound is cellulose. Microbial utilization of this waste for enzyme production purposes, especially cellulase, is a breakthrough that may lead to reduce production costs. Initial investigations showed that Aspergillus sp. VTM1 through solid-state fermentation (SSF) could produce cellulases. Optimal cellulase could be produced if 10 g coffee pulp with 10% moisture is inoculated using 10⁸ spores/mL of Aspergillus sp. VTM1 for 48 hours at 30 °C. Hydrolysis of 1% carboxymethyl cellulose (CMC) substrate in 50 mM acetate buffer pH 5 by this cellulase showed that the enzyme activity reached up to 1.18 U/mL. The optimum pH of the enzyme was 5 and stable at 3-3.5 and 4-7. The success of the first step of this investigation will be a cheap way of producing cellulases.

Abstract: Palm fruit bunch (PFB) and palm fruit residue (PFR) are considered as potential raw materials for ethanol production due to their large availability from palm oil industry. However, the presence of lignin can retard the rate of enzymatic hydrolysis. Both PFB and PFR were pretreated with a 10% w/v sodium hydroxide solution. The amounts of their hemicellulose were substantially decreased whereas their lignin contents were slightly reduced. After that, they were hydrolyzed using cellulase from Trichoderma reesei (ATCC 26921) at 50 °C and pH 5. An addition of Tween 80, nonionic surfactant, with 0.25% w/v concentration provided an increase in reducing sugar production about 50.5% at 10 FPU/g PFB cellulase loading, while the addition of Tween 80 with 0.5% w/v concentration increased reducing sugar production by 38.8% at 20 FPU/g PFR cellulase loading. The greater the amount of lignin in the lignocellulosic materials, the higher the dosages of enzyme and surfactant required for the enzymatic hydrolysis. The adsorption of added nonionic surfactant onto the hydrophobic surface of lignin resulted in an increase in the availability of added enzyme to both cellulose and hemicellulose, leading to the enhancement of enzymatic hydrolysis. Additionally, the adsorption of cellulase on PFB and PFR were well fitted with the Freundlich isotherm.

Abstract: In this study,the cellulase-producing ability of Aspergillus niger FC-1 through solid-state fermentation (SSF) and characteristics of the cellulase were investigated. The maximum activities of total cellulase (FPase) and endoglucanase (CMCase) were 8.2 and 31.5 IU per gram of dried substrate respectively after 96-h incubation period. The activities of both FPase and CMCase produced by Aspergillus niger FC-1 exhibited the optimal values at pH 5.5 and 50°C(as shown in Fig.2). Thermostability and pH stability of the enzymes were respectively appreciable at temperature ranging from 45°C to 55°C, pH ranging from 5.0 to 5.5. In addition, with an optimal 1:10 (w/v) substrate to moisture ratio (a cellulase loading of 8.5 FPU per cellulose), the glucose concentration was as high as 36.6 g glucose l^-1 for a 48 h hydrolysis of corncob residues.

Abstract: Cellulases, among many enzymes, have been highlighted in several areas of expertise, such as food, textiles, pulp and paper and wastewater treatment of effluents and residues. There is also the challenge of producing biofuels, where currently cellulases have been widely applied in the production of cellulosic ethanol, where it is used during the stage of hydrolysis of lignocellulosic biomass for conversion of cellulose to glucose. Studies have been developed in order to produce this enzyme through a process of solid state fermentation from lignocellulosic agroindustrial wastes, thus reducing the cost of enzyme production, and adding value to the residue. The aim of this work was to produce cellulases from the stalk of the cashew bagasse using Trichoderma reesei LCB 48. The study of the cellulase production was performed using 22 factorial design with central point in quadruplicate. The washed stalk of the cashew bagasse inoculated with T. reesei was evaluated for the production of cellulases with initial moisture contents of 45, 55 and 65% and in the presence of inorganic nitrogen ((NH4)₂SO₄) at concentrations 0.5, 0.75 and 1%. The fermentation was developed over 238 hours, and during this period the parameters analyzed were pH, moisture, AR and enzyme activity expressed in CMCase. Peak production of cellulase enzyme expressed in CMCase was achieved with 238 hours which value was 0.71 U/g (0.095 U/mL), under the conditions of 45% initial moisture content and 1% of nitrogen source. This activity was obtained in only one stage of the biotechnological process, the solid state fermentation; the next ones are concentration and purification. The using of experimental design methodology allowed us to observe the initial substrate moisture is the determining variable in the production of enzymes CMCases, and the minimum moisture level (45%) showed the highest production values of CMCase.

Abstract: A preliminary study was performed on enzymatic hydrolysis process for treating empty fruit bunch (EFB) fibre. The bioconversion of cellulose hydrolysis was carried out with soluble cellulase from Trichoderma reesei as the biocatalyst. Crucial trends such as substrate and enzyme loading influencing the enzymatic reaction were also studied in order to enhance the cellulose conversion. The results indicate that as the enzyme loading was increased, the EFB conversion also increased until it reached 115.63 FPU/g of enzyme concentration, beyond this values, the reverse occurred. On the other hand, as the substrate loading was increased the conversion decreased. Inhibition of enzyme adsorption by hydrolysis products appear to be the main cause of the decreasing conversion at increasing enzyme loading and substrate loading.

Abstract: This study aimed to analyze the kinetics of enzymatic hydrolysis of cellulose. Cellulase enzyme was obtained from Aspergillus niger grown on filter paper and the hydrolysis process was carried out in solid state. The kinetic reviewed here was the relationship between glucose production and cellulose mass reduction to optimize the parameters of Monod equation at various moisture levels.

Abstract: This paper made the detailed discourse for the study on using cellulase, hemicellulase hydrolysis of poplar fiber raw material to make glucose. The raw material used in this experiment is poplar, cellulase and hemicellulase enzymes are used. Hemicellulase is a complex system, xylose is regarded as the main chain for a lot of hemicellulose. The experiment used dry poplar as raw material, through the ball mill, ground poplar into wood powder. In the experiment, the optimal condition of enzyme hydrolysis of wood powder has been discussed based on reaction temperature, reaction time, enzyme concentration, and the pH value of reaction. Finally, under the optimal condition, use enzyme to hydrolyse wood powder, measure reducing sugar content by the DNS method, and calculate the rate of hydrolysis.

Abstract: The paper discussed the extraction process of rubusoside from Rubus suavissimus using a new technique named cellulase pretreatment approach. First, the parameters of cellulose which generate the optimized condition for the extraction of rubusoside from Rubus suavissimus were identified. Under the most optimal condition, the extraction efficiency is maximal. The parameters include pH value,temperature and enzyme-substrate ratio. Second, single factor experiment and an orthogonal test then could be conducted to obtain the optimized condition for the extraction process with the assistances of cellulose. The parameters under the optimized condition were determined as following: ethanol as solvent, 1.2% cellulose, 40°C, pH 4.8 and duration 25 minutes. The result shows that the extraction efficiency of rubusoside is 10.81%.