Top PDF Process for enzymatic hydrolysis of starch to glucose

Process for enzymatic hydrolysis of starch to glucose

Process for enzymatic hydrolysis of starch to glucose

Process for enzymatic hydrolysis of starch to glucose Abstract A process for converting starch or partially hydrolyzed starch into a syrup containing dextrose includes the steps of saccharifying starch hydrolyzate in the presence of a saccharifying starch hydrolyzate in the presence of a mutated glucoamylase or related enzyme and increasing the selectivity of the enzyme for α-(1→4)- glucosidic bonds by the glucoamylase or related enzyme by including at least one mutation, the mutation substituting an amino acid of the enzyme with at least one amino acid chosen by comparison with structurally related regions of other enzymes that selectively hydrolyze only α-(1→4) glucosidic bonds. Enzymes made in accordance with the present invention are also disclosed.
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Optimization of bioconversion process for trehalose production from enzymatic hydrolysis of kudzu root starch using a visualization method

Optimization of bioconversion process for trehalose production from enzymatic hydrolysis of kudzu root starch using a visualization method

With respect to starch content and yield, kudzu is con- sidered to rival the carbohydrate production from maize and sugar cane (Sage et al. 2009). For a better trehalose production, a higher maltose concentration with a lower glucose concentration was preferable with kudzu starch hydrolysate as the substrate. Previous studies suggested that the liquefaction DE value of starch was found to influence the saccharide composition, and the optimum liquefaction DE of starch for maltose syrup production was 8–11 (Marchal et al. 1999). Both a too high and too low DE value can significantly affect the production of maltose, the former one causes a rapid decrease of malt- ose yield, while the latter one results in a high viscosity which is harmful to the following saccharification process (Besselink et al. 2008). In this study, α -amylase was used to hydrolyze kudzu root starch granules to obtain utmost maltose. Our preliminary experiments showed that it needed only 8 min of liquefaction time to reach a DE value of 8–11 with kudzu root starch, which was faster than rice and corn starch (e.g., 22–27 min) (Additional file 2: Figure S2) (Roy and Gupta 2004). Small granules in kudzu root could be the most possibly reason to increase enzyme susceptibility and easily to be liquefied (Kim and Robyt 1999). However, the optimal DE value was finally selected among 19–21 to obtain the utmost starch utili- zation and maltose content in the present study (Addi- tional file 3: Figure S3, Additional file 4: Table S1).
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PRODUKSI SIRUP GLUKOSA HASIL HIDROLISIS ENZIMATIS PATI GARUT ( Glucose syrup from enzymatic hydrolysis of arrowroot starch)

PRODUKSI SIRUP GLUKOSA HASIL HIDROLISIS ENZIMATIS PATI GARUT ( Glucose syrup from enzymatic hydrolysis of arrowroot starch)

maltose and 33.472% glucose. Key word : glucose syrup, arrowroot strach, α-amylase, glukoamylase ABSTRAK Tujuan penelitian ini yaitu membuat sirup glukosa dari pengaruh konsetrasi pati garut , pH sakarifikasi ( Penelitian I ) ; pengaruh konsentrasi enzim glukoamilase dan lama sakarifikasi ( Penelitian II) . Penelitian ini menggunakan Rancangan Acak Lengkap terdiri dari dua faktor dengan dua kali ulangan. Faktor pertama pada penelitian I yaitu konsentrasi pati garut (25;

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A Kinetic Study of the Enzymatic Hydrolysis of Cassava Starch

A Kinetic Study of the Enzymatic Hydrolysis of Cassava Starch

Mechanized Process The outer corky layer of skin on the cassava root is cleaned off with any adhering dirt during washing. However, the thick inner layer of skin, which also contain starch is not usually peeled off. Washing is achieved using brush washers. The cleaned cassava roots are grated into pulp using raspers driven by engines. For industrial screening, mechanized rotating screens are used. Water is sprayed into the pulp as it passes through the screening equipment. The starch water is caught in a cement basin below the whole screen length, from where it runs along channels into sedimentation tanks or starch tables. The washed out pulp is dried and pulverized into an off grade flour. Settling is done m settling tanks. Chemicals such as alum (aluminium sulphate) are added to aid sedimentation. The moisture content is reduced to about 35-40% with centrifuges, with final drying done by evaporators. The starch flour is then packed [3].
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Yellow Sweet Potato Starch Hydrolysis Into Glucose Enzymatically

Yellow Sweet Potato Starch Hydrolysis Into Glucose Enzymatically

Glucose is a monosaccharide found in many fruits, and plants obtained through a process using enzyme hydrolysis of starch saccharide. Sweet potato starch Hydrolisis run with three neck flask equipped with a stirrer. In Liquifikasi stage, three"neck flask is inserted into the starch solution which has been set temperature and the pH was added HCI and in the heat, then added α"amylase enzyme in a certain time. Saccharification second stage, where the results liquification cooled, set the temperature and pH on certain conditions. Then added enzyme giukoamilase by volume according to the specified variable, and incubated at a given time. At a certain time interval was taken a few examples of the analyzed samples will be analyzed glucose levels Process behavior observed in this study were changes in temperature, hydrolysis time and the addition of enzymes, the best hydrolysis results obtained at 60 ° C, pH 4.5 and the addition of 0.7 ml of glucoamylase and time hydrolysis 5 days with glucose levels reaching 5 , 65% and conversion yield of 66.8% and 22.59%.
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Enzymatic Hydrolysis Of Poly (Lactic Acid) (Pla) And Thermoplastic Starch (Tps)

Enzymatic Hydrolysis Of Poly (Lactic Acid) (Pla) And Thermoplastic Starch (Tps)

Such factors may be biotic or abiotic. In addition, characteristics such as crystallinity, morphology and the surface profile of the materials may influence its degradation. In this context, the aim of this work is to understand the enzymatic hydrolysis process for two biodegradable polymers with adverse behavior, thermoplastic starch (TPS), poly (lactic acid) (PLA) and their blends. The materials were characterized by contact angle (CA) and scanning electron microscopy (SEM). The samples were submitted to the enzymatic hydrolysis assay in the presence of the α-amylase and proteinase K enzymes. The results obtained allow us to conclude that the incorporation of TPS in the matrix of the PLA confers greater roughness to the mixtures, making them more susceptible to hydrolysis and consequent biodegradation. With respect to the enzymatic hydrolysis, it was possible to conclude that the samples showed higher affinity with the proteinase-K enzyme.
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Hydrothermal Pretreatment Enhanced Enzymatic Hydrolysis and Glucose Production from Lignocellulose Biomass

Hydrothermal Pretreatment Enhanced Enzymatic Hydrolysis and Glucose Production from Lignocellulose Biomass

2.4 Enzymatic Hydrolysis The inoculum containing crude enzymes were used cellulases from Aspergillus niger and Trichoderma worked in Department of Biotechnology. The pretreated sawdust samples from hardwood and softwood were hydrolysed by cellulases from Aspergillus niger and Trichoderma at 50˚C, 85rpm in a water bath shaker with cellulose 5% (w/v).The cellulose powder was dissolved in 1ml of 0.05M citrate buffer (pH 4.8).At each reaction time of 60min, 0.5ml of sample was taken and diluted for the glucose and the total reducing sugar analysis. In the enzymatic hydrolysis, filter paper, pretreated hardwood (HS-5) and softwood (SS-5) were used as the substrates. At the end of the hydrolysis period, DNS reagent was added to stop the reaction. Then the process for colour development was continued. The undigested pulps were settled, separated and absorbance of liquid portion was measured to find the amount of glucose produced. The untreated pulp was washed with water, dried at 100 °C and weighed for determination of solid conversion.
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Optimization of Enzymatic Hydrolysis of Manihot esculenta Root Starch by Alpha-Amylase and Glucoamylase Using Response Surface Methodology

Optimization of Enzymatic Hydrolysis of Manihot esculenta Root Starch by Alpha-Amylase and Glucoamylase Using Response Surface Methodology

2.3 Statistical Analysis for Experimental Design In order to maximize the glucose production, full factorial design for three independent variables was adopted. Full factorial design was used to obtain the combination of values that can optimize the response within the region of the three dimensional observation spaces, which allows one to design a minimal number of experimental runs. The variables were temperature, time and pH for this study. The actual values of the variables at coded levels -1, 0 and + 1 are given in Table 1. The selection of low, middle and high levels for all these variables were based on a prior screening done in the laboratory (unpublished data). A 2 3 full factorial design with 2 replicates at the center point, leading to the total number of 10 experiments. The behaviour of the present system described by the following equation (1), which includes all interaction terms regardless of their significance
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Parameter estimation of tapioca starch hydrolysis process: application of least squares and genetic algorithm

Parameter estimation of tapioca starch hydrolysis process: application of least squares and genetic algorithm

1 Faculty of Chemical and Natural Resources Engineering, 2 Faculty of Mechanical Engineering, Universiti Teknologi Malaysia, 81310 UTM, Skudai, Johor. ABSTRACT The performance of genetic algorithm (GA) in nonlinear kinetic parameter estimation of tapioca starch hydrolysis was studied and compared with the Gauss-Newton method. Both methods were employed for determining the model parameters of the modified version of Gonzalez-Tello model. To estimate and validate the model parameters, experimental works involving hydrolysing tapioca starch were conducted. The model was then used to predict glucose concentration profile for a given initial condition of the tapioca hydrolysis process. In terms of error index values, both methods produced good results. This study showed that the impact of user defined parameters of the GA was insignificant as compared with the influence of initial parameters of the Gauss-Newton method on the predictive performance. Furthermore, the GA approach requires no guessing of the initial values and is able to produce reasonable solutions for the estimated parameters.
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Optimal control of enzymatic hydrolysis of lignocellulosic biomass

Optimal control of enzymatic hydrolysis of lignocellulosic biomass

percentage increase in endoglucanase and exoglucanase or β-glucosidase required to achieve the glucose concentrations mentioned in Table 2 for fixed batch times. Among the two enzyme mixtures, the requirement of E 1 is relatively higher than E 2 . This could be because, addition of E 1 results in forma- tion of cellobiose and glucose through r 1 and r 2 whereas, E 2 produces glucose through r 2 and r 3 . Considering the fact that endoglucanase and exoglucanase mixtures as well as β-glucosidase are expensive, instead of using either of these enzymes, equal percentage of both can also be used. The per- centage of additional enzyme required in absence of optimal control was reduced when both enzymes were used instead of using one of them. This reduction could be due to the synergism between the enzymes. These results demonstrate the use of optimal control in improving the process efficiency without increasing the enzyme required.
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Enzymatic hydrolysis of bitter sorghum for bioethanol production

Enzymatic hydrolysis of bitter sorghum for bioethanol production

For the purpose of bioethanol production, conversion of starch to fermentable sugars is required. Starch conversion is achieved by enzymatic hydrolysis. The enzymes α- and β- amylases are necessary for hydrolysis and are present within the sorghum grain endosperm (Palmer, 1992). Starch is composed of amylose and amylopectin, which are high molecular weight molecules. Amylose is a linear molecule made up of α-(1-4)-D- glucopyranose (Dicko et al., 2006). Amylopectin is a branched molecule made up of α- (1-4)-D-glucopyranose and α-(1-6)-D-glucopyranose (Dicko et al., 2006). During starch hydrolysis α- and β-amylases act on the α-(1-4) linkages. Αlpha-amylases are endoenzymes and are involved in starch liquefaction. Beta-amylases are exoenzymes and are involved in starch saccharification (Dicko et al., 2006). However, low β-amylase activity of sorghum grains leads to limited fermentable extract (Agu and Palmer, 1998). Thus sorghum processing for bioethanol production usually exploits the addition of commercial enzymes. du Preez et al. (1985) used sorghum grains for bioethanol production via a dual-enzymatic process. The enzymes used were Termamyl 120L and AMG 200L (du Preez et al., 1985). Sorghum hydrolyzate was obtained by liquefaction and saccharification of flaked sorghum grains in a bioreactor. For liquefaction, Termamyl 120L, which is an α-amylase was added at a temperature of 60°C for 60 minutes. For saccharification, AMG 200L, an amyloglucosidase was added at a temperature of 65°C for 120 minutes (du Preez et al., 1985). The hydrolyzate was fermented using
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Comparative Study between Neural Network Model and Mathematical Models for Prediction of Glucose Concentration during Enzymatic Hydrolysis

Comparative Study between Neural Network Model and Mathematical Models for Prediction of Glucose Concentration during Enzymatic Hydrolysis

ANNs can handle incomplete data and deal with nonlinear problems. It can also perform prediction and generalization immediately after the training process [5]. Artificial NNs seem to be a feasible alternative in several instances, and their application for biotechnological processes is continuously growing [6]. With respect to biotechnological processes in particular, several studies can be found in literature, such as the description of the α-amilase inactivation, the prediction of the final concentration of ethanol in a batch fermentation process and as a soft-sensor [7-9]. ANN models are generally used for prediction, function approximation, classification, and clustering [10]. However, few papers were reported about ANN-basedmodel for enzymatic hydrolysis. The aim of the present study is to check the validity of ANN to predict the glucose production under various enzymatic hydrolysis conditions with available experimental data and compare ANN results with kinetic model results.
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Effects of hot-washing process on structure and enzymatic hydrolysis of treated steam explosion corn stover

Effects of hot-washing process on structure and enzymatic hydrolysis of treated steam explosion corn stover

bilized lignin. The previous works have characterized the glass transition behavior of lignin, where it trans- forms from a hard or glass-like state into a rubbery or viscous state upon heating (Ko et al. 2015). Hot-water pretreatments reaching temperatures above the range for lignin phase transition cause lignin to coalesce into larger molten bodies that migrate within and out of the cell wall, and can redeposit on the surface of plant cell walls upon cooling (Donohoe et al. 2008). During cool- ing after pretreatment, coalesced lignin could harden and either became trapped within the cell wall layers or settle out of the bulk liquid phase, potentially deposit- ing back onto the biomass surface. Typically, the solid fraction is separated by filtration. The solid fraction allows solubilized lignin to condense and precipitate out on the cellulosic residue interfering with the enzy- matic hydrolysis of cellulose to glucose (Selig et al. 2007). Flow-through hot-water pretreatment, where the sol- ids residence time is longer than that of the liquid, has been shown to effectively dissolve more lignin compared with pretreatments, in which liquid and solids have the same residence time (Mosier et al. 2005). This method also generates solids that are more reactive on enzymatic hydrolysis, because of removing the solubilized lignin. However, continuous flow-through operation is thought to use an excessive amount of water and energy (Liu and Wyman 2005).
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Cassava Pulp as a Biofuel Feedstock of an Enzymatic Hydrolysis Proces

Cassava Pulp as a Biofuel Feedstock of an Enzymatic Hydrolysis Proces

Carbohydrate composition of cassava pulp was analyzed, and summarized in Table 1. Total glucose derived from starch, cellulose and soluble portion occupied approximately 94.7% of dry matter. Starch was the main polysaccharide in cassava pulp, comprising 65.6±1.6% and 39.4% of dry and wet matters, respectively. Non-starch polysaccharide contains fibrous materials, cellulose, hemicelluloses, pectin, protein and lignin, of 20.1%, 8.1%, 2.8%, 7.0%, 3.1%, 2.2%, respectively. A high starch constituent within a waste reflects an efficiency level of starch extraction process from a tapioca factory. The cassava pulp was dried below the starting gelatinization temperature of cassava starch to preserve the physical characteristics of the starch granules [11], hemicelluloses [12] and lignin [13]. Fibers content 20.1% of cassava pulp which is reported in this study was lower than previous reported by Kosugi [8], Rattanachomsri [7], Sriroth [4], Thongchul [14] which were 29%, 23.0%, 27.75% and 35.9%, respectively.
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Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation

Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation

The higher yield of saccharides is usable for increase of the following fermentation effectivity. In this study optimal conditions (pH and temperature) for amylolytic enzymes were searched. As raw material was used waste bread. Two analytical methods for analysis were used. Efficiency and process of hydrolysis was analysed spectrophotometrically by Somogyi-Nelson method. Final yields of glucose were analysed by HPLC.

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Techno-economic Implications of Fed-batch Enzymatic Hydrolysis

Techno-economic Implications of Fed-batch Enzymatic Hydrolysis

Overview of production process Pretreatment After the feedstock arrives at the plant facility it is first washed and ground to reduce particle size. Then pretreatment begins. Our design uses a thermal hydrolysis (hot steam) pretreatment. The thermal hydrolysis pretreatment will degrade the structure of the biomass and leave the cellulose more accessible to the enzyme in the upcoming enzymatic hydrolysis operation. Hot, high-pressure steam is fed into the reactor at a rate of 30 MT/h, temperature of 200°C and pressure of 10 bar. The feedstock slurry enters the reactor at 215 MT/h, 88°C and 10 bar. Within the reactor, the contents sit at 180°C and 10 bar. The residence time is 30 minutes. During this time some cellulose is broken down into glucose, and a majority of the hemicellulose is broken down into xylose. The conversion of cellulose to glucose is set to 10%. The conversion of hemicellulose to xylose is set to 70%. The pretreatment reaction is assumed to be adiabatic.
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STUDIES ON THE PHYSICOCHEMICAL PROPERTIES OF MICROCRYSTALLINE STARCH OBTAINED BY ENZYMATIC HYDROLYSIS USING α-AMYLASE ENZYME

STUDIES ON THE PHYSICOCHEMICAL PROPERTIES OF MICROCRYSTALLINE STARCH OBTAINED BY ENZYMATIC HYDROLYSIS USING α-AMYLASE ENZYME

respectively. The dilution potential of this modified starch was determined using ascorbic acid and metronidazole and was found to be 40:60 (40% drug: 60% filler-binder). These physical properties were compared with those of microcrystalline cellulose which was used as a basis for comparison. The physicochemical properties of this modified starch form a basis for the development of model tablet formula for directly compressed ascorbic acid and metronidazole tablets.

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A study of chickpea (Cicer arietinum L.) seed starch concentration, composition and enzymatic hydrolysis properties

A study of chickpea (Cicer arietinum L.) seed starch concentration, composition and enzymatic hydrolysis properties

extrinsic component reflects the appearance of seed, while intrinsic component is governed by the seed composition. As a first step towards chickpea seed composition improvement in western Canada, it is important to characterize the extrinsic characteristics and selected seed constituents in currently grown chickpea varieties. To develop breeding strategies for seed quality improvement it is imperative to study the genotype x environment interactions and repeatability of selected seed quality traits. There are limited published reports about chickpea seed composition, but no systematic study to characterize genetic variation that exists in chickpea gene pool. Although chickpea derived food products have been shown to have low glycemic indices and increased amounts of resistant starch, there are no systematic studies to associate these characteristics with chickpea seed composition. The main objective of this research is to characterize chickpea seed composition and understand the influence of genotype and environment on deposition of seed starch and its composition. Selected global chickpea germplasm will be analyzed for genetic variation in seed protein and starch composition. Attempts will aso be made to study the difference in desi and kabuli chickpea cultivars seed starch composition, structure and associate these properties with digestibility using an in vitro enzymatic assay. Successful completion of this project will result in a better understanding of chickpea seed composition and strategy (ies) for chickpea seed quality improvement. The specific objectives of this study were to:
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Modelling of enzymatic protein hydrolysis

Modelling of enzymatic protein hydrolysis

72 The calculated regression results using the obtained model parameters for the degree of hydrolysis as well as heat released at different enzyme concentrations and buffer type are observed in Figure 4-5 and Figure 4-6. As can be seen in Figure 4-5 and Figure 4-6 the present model shows a poor prediction of the experimental data. However, the current model seems to predict the experimental data better than the model presented by Marquez-Moreno and Fernandez-Cuadrado (1993) as indicated by 𝑅 2 in Table 4-5 and the absolute error values in Table A-5a, appendix A.2.2. The proposed model has the smallest absolute error of 18.04 % and 14.67 % less than the model found in the literature for heat flow and the degree of hydrolysis predicted compared to experimental data. These observations were expected since empirical models are not based on the fundamentals of the process. Also, empirical models do not hold when applied outside their derived conditions. These results indicate that complex models such as population balance approach and multiple substrate Michaelis-Menten equation can be used to describe enzymatic protein hydrolysis better than over-simplified models without theoretical meaning. In summary, the proposed model for endopeptidase action predicted the experimental data better than the model found in the literature.
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Enzymatic Hydrolysis of Paulownia Pulp

Enzymatic Hydrolysis of Paulownia Pulp

cellulose synthase through the genetic cloned RNA segment, which has significantly improved people’s understanding in the cellulose biosynthesis process [18]. As introduced, CesA is the basic unit in the cellulose biosynthesis process. It has been reported that there are two active sites in one unit of CesA. A proposed mechanism is that during the polymerization process, two UDP-α-glucopyranose molecules are first attached to the two active sites. The enzyme is capable of inverting the reducing end of the substrates from α to β while catalyzing the formation of glycosidic bonds on the non- reducing end of the cellulose chain. After the polymerization, cellulose chain is extruded through the enzyme and leaves the active sites available for later substrates [19]. Since the enzyme adds two UDP-α-glucopyranose molecules simultaneously on the cellulose chain, the polymerization is also called the dual addition process. One controversial point lies in the cleavage of UDP units. Whether the UDP units need to be cleaved before the extrusion of the cellulose chain is still not clear.
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