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Sample records for enzymatic hydrolysis process

  1. Dynamic modeling and validation of a lignocellulosic enzymatic hydrolysis process

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Sin, Gürkan

    2013-01-01

    The enzymatic hydrolysis process is one of the key steps in second generation biofuel production. After being thermally pretreated, the lignocellulosic material is liquefied by enzymes prior to fermentation. The scope of this paper is to evaluate a dynamic model of the hydrolysis process...... on a demonstration scale reactor. The following novel features are included: the application of the Convection–Diffusion–Reaction equation to a hydrolysis reactor to assess transport and mixing effects; the extension of a competitive kinetic model with enzymatic pH dependency and hemicellulose hydrolysis......; a comprehensive pH model; and viscosity estimations during the course of reaction. The model is evaluated against real data extracted from a demonstration scale biorefinery throughout several days of operation. All measurements are within predictions uncertainty and, therefore, the model constitutes a valuable...

  2. Influence of enzymatic hydrolysis on the allergenic reactivity of processed cashew and pistachio.

    Science.gov (United States)

    Cuadrado, Carmen; Cheng, Hsiaopo; Sanchiz, Africa; Ballesteros, Isabel; Easson, Michael; Grimm, Casey C; Dieguez, M Carmen; Linacero, Rosario; Burbano, Carmen; Maleki, Soheila J

    2018-02-15

    Cashew and pistachio allergies are considered a serious health problem. Previous studies have shown that thermal processing, pressurization and enzymatic hydrolysis may reduce the allergenic properties of food by changing the protein structure. This study assesses the allergenic properties of cashew and pistachio after thermal treatment (boiling and autoclaving), with or without pressure (autoclaving), and multiple enzymatic treatments under sonication, by SDS-PAGE, western blot and ELISA, with serum IgE of allergic individuals, and mass spectroscopy. Autoclaving and enzymatic hydrolysis under sonication separately induced a measurable reduction in the IgE binding properties of pastes made from treated cashew and pistachio nuts. These treatments were more effective with pistachio allergens. However, heat combined with enzymatic digestion was necessary to markedly lower IgE binding to cashew allergens. The findings identify highly effective simultaneous processing conditions to reduce or even abolish the allergenic potency of cashew and pistachio. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Bioethanol production: an integrated process of low substrate loading hydrolysis-high sugars liquid fermentation and solid state fermentation of enzymatic hydrolysis residue.

    Science.gov (United States)

    Chu, Qiulu; Li, Xin; Ma, Bin; Xu, Yong; Ouyang, Jia; Zhu, Junjun; Yu, Shiyuan; Yong, Qiang

    2012-11-01

    An integrated process of enzymatic hydrolysis and fermentation was investigated for high ethanol production. The combination of enzymatic hydrolysis at low substrate loading, liquid fermentation of high sugars concentration and solid state fermentation of enzymatic hydrolysis residue was beneficial for conversion of steam explosion pretreated corn stover to ethanol. The results suggested that low substrate loading hydrolysis caused a high enzymatic hydrolysis yield; the liquid fermentation of about 200g/L glucose by Saccharomyces cerevisiae provided a high ethanol concentration which could significantly decrease cost of the subsequent ethanol distillation. A solid state fermentation of enzymatic hydrolysis residue was combined, which was available to enhance ethanol production and cellulose-to-ethanol conversion. The results of solid state fermentation demonstrated that the solid state fermentation process accompanied by simultaneous saccharification and fermentation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  4. Dynamic Simulation, Sensitivity and Uncertainty Analysis of a Demonstration Scale Lignocellulosic Enzymatic Hydrolysis Process

    DEFF Research Database (Denmark)

    Prunescu, Remus Mihail; Sin, Gürkan

    2014-01-01

    This study presents the uncertainty and sensitivity analysis of a lignocellulosic enzymatic hydrolysis model considering both model and feed parameters as sources of uncertainty. The dynamic model is parametrized for accommodating various types of biomass, and different enzymatic complexes...

  5. Utilization of residue from cassava starch processing for production of fermentable sugar by enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Luciana Reis Fontinelle SOUTO

    Full Text Available Abstract The aim of this study was to characterize and perform enzymatic hydrolysis of cassava peeling residue (peel and inner peel, mainly composed of peels and small pieces. Residue was sanitized, dried at 55 °C for 24 hours and ground. The obtained flour showed pH of 4.85; 72.53 g 100 g–1 moisture; 5.18 mL 1M NaOH 100 g–1 acidity; 60.68 g 100 g–1 starch; 1.08 g 100 g–1 reducing sugar; 1.63 g 100g–1 ash; 0.86 g 100 g–1 lipid and 3.97 g 100 g–1 protein. Enzymatic hydrolysis was carried out by means of rotational central composite design, analyzing the effects of concentrations of α-amylase enzyme (10 to 50 U g starch–1, and the amyloglucosidase enzyme (80 to 400 U g starch–1 on variable responses: percent conversion of starch into reducing sugars (RSC and soluble solid content (SS. Highest values of RSC (110% and SS (12 °Brix were observed when using the maximum concentration of amyloglucosidase and throughout the concentration range of α-amylase. Enzymatic hydrolysis of cassava peel is feasible and allows the use of hydrolysate in fermentation processes for the production of various products, such as alcoholic drinks, vinegar, among others.

  6. Utilization of residue from cassava starch processing for production of fermentable sugar by enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Luciana Reis Fontinelle SOUTO

    2016-01-01

    Full Text Available Abstract The aim of this study was to characterize and perform enzymatic hydrolysis of cassava peeling residue (peel and inner peel, mainly composed of peels and small pieces. Residue was sanitized, dried at 55 °C for 24 hours and ground. The obtained flour showed pH of 4.85; 72.53 g 100 g–1 moisture; 5.18 mL 1M NaOH 100 g–1 acidity; 60.68 g 100 g–1 starch; 1.08 g 100 g–1 reducing sugar; 1.63 g 100g–1 ash; 0.86 g 100 g–1 lipid and 3.97 g 100 g–1 protein. Enzymatic hydrolysis was carried out by means of rotational central composite design, analyzing the effects of concentrations of α-amylase enzyme (10 to 50 U g starch–1, and the amyloglucosidase enzyme (80 to 400 U g starch–1 on variable responses: percent conversion of starch into reducing sugars (RSC and soluble solid content (SS. Highest values of RSC (110% and SS (12 °Brix were observed when using the maximum concentration of amyloglucosidase and throughout the concentration range of α-amylase. Enzymatic hydrolysis of cassava peel is feasible and allows the use of hydrolysate in fermentation processes for the production of various products, such as alcoholic drinks, vinegar, among others.

  7. Enzymatic hydrolysis of plant extracts containing inulin

    Energy Technology Data Exchange (ETDEWEB)

    Guiraud, J.P.; Galzy, P.

    1981-10-01

    Inulin-rich extracts of chicory and Jerusalem artichoke are a good potential source of fructose. Total enzymatic hydrolysis of these extracts can be effected by yeast inulinases (EC 3.2.1.7). Chemical prehydrolysis is unfavourable. Enzymatic hydrolysis has advantages over chemical hydrolysis: it does not produce a dark-coloured fraction or secondary substances. It is possible to envisage the preparation of high fructose syrups using this process. (Refs. 42).

  8. Process evaluation of enzymatic hydrolysis with filtrate recycle for the production of high concentration sugars.

    Science.gov (United States)

    Xue, Ying; Rusli, Jannov; Chang, Hou-Min; Phillips, Richard; Jameel, Hasan

    2012-02-01

    Process simulation and lab trials were carried out to demonstrate and confirm the efficiency of the concept that recycling hydrolysate at low total solid enzymatic hydrolysis is one of the options to increase the sugar concentration without mixing problems. Higher sugar concentration can reduce the capital cost for fermentation and distillation because of smaller retention volume. Meanwhile, operation cost will also decrease for less operating volume and less energy required for distillation. With the computer simulation, time and efforts can be saved to achieve the steady state of recycling process, which is the scenario for industrial production. This paper, to the best of our knowledge, is the first paper discussing steady-state saccharification with recycling of the filtrate form enzymatic hydrolysis to increase sugar concentration. Recycled enzymes in the filtrate (15-30% of the original enzyme loading) resulted in 5-10% higher carbohydrate conversion compared to the case in which recycled enzymes were denatured. The recycled hydrolysate yielded 10% higher carbohydrate conversion compared to pure sugar simulated hydrolysate at the same enzyme loading, which indicated hydrolysis by-products could boost enzymatic hydrolysis. The high sugar concentration (pure sugar simulated) showed inhibition effect, since about 15% decrease in carbohydrate conversion was observed compared with the case with no sugar added. The overall effect of hydrolysate recycling at WinGEMS simulated steady-state conditions with 5% total solids was increasing the sugar concentration from 35 to 141 g/l, while the carbohydrate conversion was 2% higher for recycling at steady state (87%) compared with no recycling strategy (85%). Ten percent and 15% total solid processes were also evaluated in this study.

  9. An integrated green process: Subcritical water, enzymatic hydrolysis, and fermentation, for biohydrogen production from coconut husk.

    Science.gov (United States)

    Muharja, Maktum; Junianti, Fitri; Ranggina, Dian; Nurtono, Tantular; Widjaja, Arief

    2018-02-01

    The objective of this work is to develop an integrated green process of subcritical water (SCW), enzymatic hydrolysis and fermentation of coconut husk (CCH) to biohydrogen. The maximum sugar yield was obtained at mild severity factor. This was confirmed by the degradation of hemicellulose, cellulose and lignin. The tendency of the changing of sugar yield as a result of increasing severity factor was opposite to the tendency of pH change. It was found that CO 2 gave a different tendency of severity factor compared to N 2 as the pressurizing gas. The result of SEM analysis confirmed the structural changes during SCW pretreatment. This study integrated three steps all of which are green processes which ensured an environmentally friendly process to produce a clean biohydrogen. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Torque measurements reveal large process differences between materials during high solid enzymatic hydrolysis of pretreated lignocellulose

    Directory of Open Access Journals (Sweden)

    Palmqvist Benny

    2012-08-01

    Full Text Available Abstract Background A common trend in the research on 2nd generation bioethanol is the focus on intensifying the process and increasing the concentration of water insoluble solids (WIS throughout the process. However, increasing the WIS content is not without problems. For example, the viscosity of pretreated lignocellulosic materials is known to increase drastically with increasing WIS content. Further, at elevated viscosities, problems arise related to poor mixing of the material, such as poor distribution of the enzymes and/or difficulties with temperature and pH control, which results in possible yield reduction. Achieving good mixing is unfortunately not without cost, since the power requirements needed to operate the impeller at high viscosities can be substantial. This highly important scale-up problem can easily be overlooked. Results In this work, we monitor the impeller torque (and hence power input in a stirred tank reactor throughout high solid enzymatic hydrolysis (Arundo donax and spruce. Two different process modes were evaluated, where either the impeller speed or the impeller power input was kept constant. Results from hydrolysis experiments at a fixed impeller speed of 10 rpm show that a very rapid decrease in impeller torque is experienced during hydrolysis of pretreated arundo (i.e. it loses its fiber network strength, whereas the fiber strength is retained for a longer time within the spruce material. This translates into a relatively low, rather WIS independent, energy input for arundo whereas the stirring power demand for spruce is substantially larger and quite WIS dependent. By operating the impeller at a constant power input (instead of a constant impeller speed it is shown that power input greatly affects the glucose yield of pretreated spruce whereas the hydrolysis of arundo seems unaffected. Conclusions The results clearly highlight the large differences between the arundo and spruce materials, both in terms of

  11. Process development for gelatinisation and enzymatic hydrolysis of starch at high concentrations

    NARCIS (Netherlands)

    Baks, T.

    2007-01-01

    cum laude graduation (with distinction) Enzymatic hydrolysis of starch is encountered in day-to-day life for instance in the dishwasher during removal of stains with detergents or in our mouth during chewing of starch-based foods in the presence of saliva. The reaction is also important for the

  12. An Integrated Process of Ionic Liquid Pretreatment and Enzymatic Hydrolysis of Lignocellulosic Biomass with Immobilised Cellulase

    Directory of Open Access Journals (Sweden)

    Mihaela Ungurean

    2014-08-01

    Full Text Available An integrated process of lignocellulosic biomass conversion was set up involving pretreatment by an ionic liquid (IL and hydrolysis of cellulose using cellulase immobilised by the sol-gel method, with recovery and reuse of both the IL and biocatalyst. As all investigated ILs, regardless of the nature of the anion and the cation, led to the loss of at least 50% of the hydrolytic activity of cellulase, the preferred solution involved reprecipitation of cellulose and lignin after the pretreatment, instead of performing the enzymatic hydrolysis in the same reaction system. The cellulose recovered after pretreatment with 1-ethyl-3-methylimidazolium acetate ([Emim][Ac] and dimethylsulfoxide (DMSO (1:1 ratio, v/v was hydrolysed with almost double yield after 8 h of reaction time with the immobilised cellulase, compared to the reference microcrystalline cellulose. The dissolution capacity of the pretreatment mixture was maintained at satisfactory level during five reuse cycles. The immobilised cellulase was recycled in nine reaction cycles, preserving about 30% of the initial activity.

  13. Process development for gelatinisation and enzymatic hydrolysis of starch at high concentrations

    OpenAIRE

    Baks, T.

    2007-01-01

    cum laude graduation (with distinction) Enzymatic hydrolysis of starch is encountered in day-to-day life for instance in the dishwasher during removal of stains with detergents or in our mouth during chewing of starch-based foods in the presence of saliva. The reaction is also important for the (food) industry, for example for the production of beer or bio-ethanol. In industry, it is usually preceded by gelatinisation to make the starch molecules available for the enzymes. Both gelatinisation...

  14. Pretreatment of sugarcane bagasse using the advanced oxidation process by electron beam for enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Ribeiro, Marcia Almeida

    2013-01-01

    The sugar cane bagasse is a renewable energy source and a raw material promise in the biofuel production, once represents about 30% of glucose contained in the plant with the potential to be hydrolyzed and then converted to ethanol. The bagasse is composed of cellulose, straight chain of glucose, of hemicellulose, an amorphous polymer consisting of xylose, arabinose, galactose, and mannose, and of lignin, a complex polymer consisting of fenilpropan units that acts as waterproof coating on the fibers, which is hard to remove due its recalcitrant nature. The aim of this work was to study the electron beam processing as a pretreatment of sugarcane bagasse to enzymatic hydrolysis of cellulose. The pretreatment of sugarcane bagasse is one of the most important steps to make this material economically viable and competitive on the energy production. As a pretreatment the electron beam processing can weak the hemicellulose and lignin structures by the action highly reactive radicals that breaks the links, reducing the degree of polymerization fibers. It was evaluated the chemical and structural modifications on fibers caused by the irradiation, the enzymatic hydrolysis of electron beam as the only pretreatment and combined to steam explosion. For enzymatic hydrolysis it was used the commercial enzymes from Novozymes. The radiation processing promotes changes in structure and composition of sugarcane bagasse, increasing the solubility, that is related to hemicellulose and cellulose cleavage, and also increasing the enzymatic conversion yield. In the case of exploded bagasse there is no changes in the enzymatic hydrolysis yield, however the electron beam processing promoted a 67% reduction of furfural, that is formed in the steam explosion process. (author)

  15. Kinetic modelling of enzymatic starch hydrolysis

    NARCIS (Netherlands)

    Bednarska, K.A.

    2015-01-01

    Kinetic modelling of enzymatic starch hydrolysis – a summary

    K.A. Bednarska

    The dissertation entitled ‘Kinetic modelling of enzymatic starch hydrolysis’ describes the enzymatic hydrolysis and kinetic modelling of liquefaction and saccharification of wheat starch.

  16. Process development of short-chain polyols synthesis from corn stover by combination of enzymatic hydrolysis and catalytic hydrogenolysis

    Directory of Open Access Journals (Sweden)

    Zhen-Hong Fang

    2014-09-01

    Full Text Available Currently short-chain polyols such as ethanediol, propanediol, and butanediol are produced either from the petroleum feedstock or from the starch-based food crop feedstock. In this study, a combinational process of enzymatic hydrolysis with catalytic hydrogenolysis for short-chain polyols production using corn stover as feedstock was developed. The enzymatic hydrolysis of the pretreated corn stover was optimized to produce stover sugars at the minimum cost. Then the stover sugars were purified and hydrogenolyzed into polyols products catalyzed by Raney nickel catalyst. The results show that the yield of short-chain polyols from the stover sugars was comparable to that of the corn-based glucose. The present study provided an important prototype for polyols production from lignocellulose to replace the petroleum- or corn-based polyols for future industrial applications.

  17. Recovery and reuse of cellulase catalyst in an enzymatic cellulose hydrolysis process

    Science.gov (United States)

    Woodward, J.

    1987-09-18

    A process for recovering cellulase from the hydrolysis of cellulose, and reusing it in subsequent hydrolyois procedures. The process utilizes a commercial adsorbent that efficiently removes cellulase from reaction products which can be easily removed by simple decantation. 1 fig., 4 tabs.

  18. Kinetics of enzymatic hydrolysis of methyl ricinoleate

    OpenAIRE

    Neeharika, T. S.V.R.; Lokesh, P.; Prasanna Rani, K. N.; Prathap Kumar, T.; Prasad, R. B.N.

    2015-01-01

    Ricinoleic acid is an unsaturated hydroxy fatty acid that naturally occurs in castor oil in proportions of up to 85–90%. Ricinoleic acid is a potential raw material and finds several applications in coatings, lubricant formulations and pharmaceutical areas. Enzymatic hydrolysis of castor oil is preferred over conventional hydrolysis for the preparation of ricinoleic acid to avoid estolide formation. A kinetics analysis of the enzymatic hydrolysis of Methyl Ricinoleate in the presence of Candi...

  19. Valorisation of tuna processing waste biomass for recovery of functional and antioxidant peptides using enzymatic hydrolysis and membrane fractionation process.

    Science.gov (United States)

    Saidi, Sami; Ben Amar, Raja

    2016-10-01

    The enzymatic hydrolysis using Prolyve BS coupled to membrane process (Ultrafiltration (UF) and nanofiltration (NF)) is a means of biotransformation of tuna protein waste to Tuna protein hydrolysate (TPH) with higher added values. This method could be an effective solution for the production of bioactive compounds used in various biotechnological applications and minimizing the pollution problems generated by the seafood processing industries. The amino acid composition, functional and antioxidant properties of produced TPH were evaluated. The results show that the glutamic acid, aspartic acid, glycine, alaline, valine and leucine were the major amino acids detected in the TPH profile. After membrane fractionation process, those major amino acids were concentrated in the NF retentate (NFR). The NFR and NF permeate (NFP) have a higher protein solubility (>95 %) when compared to TPH (80 %). Higher oil and water binding capacity were observed in TPH and higher emulsifying and foam stability was found in UF retentate. The NFP showed the highest DPPH radical scavenging activity (65 %). The NFR contained antioxidant amino acid (30.3 %) showed the highest superoxide radical and reducing power activities. The TPH showed the highest iron chelating activity (75 %) compared to other peptide fractions. The effect of the membrane fractionation on the molecular weight distribution of the peptide and their bioactivities was underlined. We concluded that the TPH is a valuable source of bioactive peptides and their peptide fractions may serve as useful ingredients for application in food industry and formulation of nutritional products.

  20. Hydrothermal treatment and enzymatic hydrolysis of Tamarix ramosissima: evaluation of the process as a conversion method in a biorefinery concept.

    Science.gov (United States)

    Xiao, Ling-Ping; Shi, Zheng-Jun; Xu, Feng; Sun, Run-Cang

    2013-05-01

    The present work investigated the effects of hydrothermal treatment (HTT) of Tamarix ramosissima by determination of sugar and inhibitor formation in the liquid fraction, and chemical and morphological changes of the pretreated solid material coupled with an evaluation of enzymatic hydrolysis. HTT was carried out in a batch reactor system at a maximal temperature (TMAX 180-240 °C) and evaluated for severities logRo ranging from 2.40 to 4.17. The liquid fractions were analyzed by HPLC, GPC, and GC-MS. The morphology and composition of the solid residues were characterized using an array of techniques, such as SEM, XRD, BET surface area, and CP/MAS (13)C NMR. Using a variety of tools, we have developed a better understanding of how HTT process affects biomass structure and cellulose properties that impact on its digestibility. These results provided new insights into the factors limiting enzymatic digestibility and mechanism of biomass deconstruction during hydrothermal process. Crown Copyright © 2012. Published by Elsevier Ltd. All rights reserved.

  1. Enzymatic hydrolysis of lactose of whey permeate

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    Karina Nascimento de Almeida

    2015-09-01

    Full Text Available The whey permeate is the residual of the concentration process of the whey proteins by ultrafiltration method. It contains important nutrients such as lactose, minerals and some proteins and lipids. It is without an ending industrial waste that causes serious damage to the environment. For its full use the lactose must be hydrolyzed to enable its consumption by intolerant people. The enzymatic hydrolysis by lactase (β-galactosidase of Kluyveromyces lactis yeast is a safe method that does not compromise the integrity of other nutrients, enabling further use of the permeate as a raw material. This study aimed to perform tests of enzymatic hydrolysis of lactose in whey permeate formulations in a concentration of 0.2%, 0.7% and 1% at 30, 60 and 90 minutes with pH 6.3 medium and 37 °C. The reactions were monitored by high performance liquid chromatography which showed that the enzyme concentration of 0.7% at time 30 minutes formulations became safe for consumption by lactose intolerant people, according to minimum levels established by law.

  2. Processing surface sizing starch using oxidation, enzymatic hydrolysis and ultrasonic treatment methods--Preparation and application.

    Science.gov (United States)

    Brenner, Tobias; Kiessler, Birgit; Radosta, Sylvia; Arndt, Tiemo

    2016-03-15

    The surface application of starch is a well-established method for increasing paper strength. In surface sizing, a solution of degraded starch is applied to the paper. Two procedures have proved valuable for starch degradation in the paper mill: enzymatic and thermo-oxidative degradation. The objective of this study was to determine achievable efficiencies of cavitation in preparing degraded starch for surface application on paper. It was found that ultrasonic-assisted starch degradation can provide a starch solution that is suitable for surface sizing. The molecular composition of starch solutions prepared by ultrasonic treatment differed from that of starch solutions degraded by enzymes or by thermo-oxidation. Compared to commercial degradation processes, this resulted in intensified film formation and in greater penetration during surface sizing and ultimately in a higher starch content of the paper. Paper sized with ultrasonically treated starch solutions show the same strength properties compared to commercially sized paper. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Pretreatment and enzymatic hydrolysis of lignocellulosic biomass

    Science.gov (United States)

    Corredor, Deisy Y.

    process. Up to 72% of hexose yield and 94% of pentose yield were obtained using "modified" steam explosion with 2% sulfuric acid at 140°C for 30 min and enzymatic hydrolysis with cellulase (15 FPU/g cellulose) and beta-glucosidase (50 CBU/g cellulose).

  4. Enzymatic hydrolysis of pretreated soybean straw

    International Nuclear Information System (INIS)

    Xu Zhong; Wang Qunhui; Jiang Zhaohua; Yang Xuexin; Ji Yongzhen

    2007-01-01

    In order to produce lactic acid, from agricultural residues such as soybean straw, which is a raw material for biodegradable plastic production, it is necessary to decompose the soybean straw into soluble sugars. Enzymatic hydrolysis is one of the methods in common use, while pretreatment is the effective way to increase the hydrolysis rate. The optimal conditions of pretreatment using ammonia and enzymatic hydrolysis of soybean straw were determined. Compared with the untreated straw, cellulose in straw pretreated by ammonia liquor (10%) soaking for 24 h at room temperature increased 70.27%, whereas hemicellulose and lignin in pretreated straw decreased to 41.45% and 30.16%, respectively. The results of infrared spectra (IR), scanning electron microscope (SEM) and X-ray diffraction (XRD) analysis also showed that the structure and the surface of the straw were changed through pretreatment that is in favor of the following enzymatic hydrolysis. maximum enzymatic hydrolysis rate of 51.22% was achieved at a substrate concentration of 5% (w/v) at 50 deg. C and pH 4.8 using cellulase (50 fpu/g of substrate) for 36 h

  5. Starch facilitates enzymatic wheat gluten hydrolysis

    NARCIS (Netherlands)

    Hardt, N.A.; Boom, R.M.; Goot, van der A.J.

    2015-01-01

    Wheat gluten can be hydrolyzed by either using (vital) wheat gluten or directly from wheat flour. This study investigates the influence of the presence of starch, the main component of wheat, on enzymatic wheat gluten hydrolysis. Wheat gluten present in wheat flour (WFG) and vital wheat gluten (VWG)

  6. Enzymatic Hydrolysis of Alkaline Pretreated Coconut Coir

    Directory of Open Access Journals (Sweden)

    Akbarningrum Fatmawati

    2013-06-01

    Full Text Available The purpose of this research is to study the effect of concentration and temperature on the cellulose and lignin content, and the reducing sugars produced in the enzymatic hydrolysis of coconut coir. In this research, the coconut coir is pretreated using 3%, 7%, and 11% NaOH solution at 60oC, 80oC, and 100oC. The pretreated coir were assayed by measuring the amount of cellulose and lignin and then hydrolysed using Celluclast and Novozyme 188 under various temperature (30oC, 40oC, 50oC and pH (3, 4, 5. The hydrolysis results were assayed for the reducing sugar content. The results showed that the alkaline delignification was effective to reduce lignin and to increase the cellulose content of the coir. The best delignification condition was observed at 11% NaOH solution and 100oC which removed 14,53% of lignin and increased the cellulose content up to 50,23%. The best condition of the enzymatic hydrolysis was obtained at 50oC and pH 4 which produced 7,57 gr/L reducing sugar. © 2013 BCREC UNDIP. All rights reservedReceived: 2nd October 2012; Revised: 31st January 2013; Accepted: 6th February 2013[How to Cite: Fatmawati, A., Agustriyanto, R., Liasari, Y. (2013. Enzymatic Hydrolysis of Alkaline Pre-treated Coconut Coir. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 34-39 (doi:10.9767/bcrec.8.1.4048.34-39[Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4048.34-39] | View in  |

  7. EFFECT OF LIGNIN CONTENT ON ENZYMATIC HYDROLYSIS OF FURFURAL RESIDUES

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    Jianxin Jiang

    2011-02-01

    Full Text Available The enzymatic saccharification of pretreated furfural residues with different lignin content was studied to verify the effect of lignin removal in the hydrolysis process. The results showed that the glucose yield was improved by increasing the lignin removal. A maximum glucose yield of 96.8% was obtained when the residue with a lignin removal of 51.4% was hydrolyzed for 108 h at an enzyme loading of 25 FPU/g cellulose. However, further lignin removal did not increase the hydrolysis. The effect of enzyme loading on the enzymatic hydrolysis was also explored in this work. It was concluded that a high glucose yield of 90% was achieved when the enzyme dosage was reduced from 25 to 15 FPU/g cellulose, which was cost-effective for the sugar and ethanol production. The structures of raw material and delignified samples were further characterized by XRD and scanning electron microscopy (SEM.

  8. Bioethanol production: Pretreatment and enzymatic hydrolysis of softwood

    Energy Technology Data Exchange (ETDEWEB)

    Tengborg, Charlotte

    2000-05-01

    The enzymatic hydrolysis process can be used to produce bioethanol from softwood, which are the dominating raw material in the Northern hemisphere. This thesis deals with the development of the process focusing on the pretreatment and the enzymatic hydrolysis stages. The influence of pretreatment conditions on sugar yield, and the effect of inhibitors on the ethanol yield, were investigated for spruce and pine. The maximum yields of hemicellulose sugars and glucose were obtained under different pretreatment conditions. This indicates that two-stage pretreatment may be preferable. The added catalysts, H{sub 2}SO{sub 4} and SO{sub 2}, resulted in similar total sugar yields about 40 g/100 g dry raw material. However, the fermentability of SO{sub 2}-impregnated material was better. This pretreatment resulted in the formation of inhibitors to the subsequent process steps, e.g. sugar and lignin degradation products. The glucose yield in the enzymatic hydrolysis stage was affected by various parameters such as enzyme loading, temperature, pH, residence time, substrate concentration, and agitation. To decrease the amount of fresh water used and thereby waste water produced, the sugar-rich prehydrolysate from the pretreatment step was included in the enzymatic hydrolysis of the solid fraction, resulting in a reduction in the cellulose conversion of up to 36%. Different prehydrolysate detoxification methods, such as treatment with Ca(OH){sub 2}, laccase, and fermentation using yeast, were investigated. The latter was shown to be very efficient. The amount of fresh water used can be further reduced by recycling various process streams. This was simulated experimentally in a bench-scale process. A reduction in fresh water demand of 50% was obtained without any further negative effects on either hydrolysis or fermentation.

  9. Application of multi-enzymatic hydrolysis for improving the efficiency of the biogas production in solid waste fermentation process in Ostróda WWTP

    Science.gov (United States)

    Lipiński, Kamil; Umiejewska, Katarzyna

    2017-11-01

    Biomass fermentation is one of the important sources of renewable energy in EU. Application of multi-enzymatic hydrolysis process enables a significant increase in efficiency of biogas production. The main goal of the paper is to present the results of the pilot scale research performed in WWTP in óstroda. The fixed combination of three enzymes was continiously introduced: amylase, lipase and protease. Research aimed at verifying the impact of enzyme dose on sludge digestion process and on the amount of biogas produced. Statistical analysis of the research results allows to determine the influence of dosing the enzymes in mesophilic digestion on the biogas production.

  10. Lactose hydrolysis in an enzymatic membrane reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mertens, B; Huyghebaert, A

    1987-10-01

    The enzymatic hydrolysis of lactose in whey permeate with subsequent recuperation of Saccharomyces lactis lactase by means of ultrafiltration was investigated. In whey permeate, S. lactis lactase shows maximal activity at pH 6.5; the optimal temperature was found to be 45/sup 0/C and is limited by strong thermal inactivation beyond this temperature. High activity combined with acceptable thermal inactivation (< 10% after 5 h incubation) was established at 30/sup 0/C. S. lactis lactase also displays considerable activity at low temperature (5/sup 0/C). Enzyme stability is reduced drastically by demineralisation: addition of low concentrations of manganese ions (10/sup -3/ M) considerably enhances stability. Using a DDS Lab-Unit 35 fitted with GR61PP polysulphon membranes (cut-off: 20.000), pilot scale experiments were carried out (pH 6.5; 30/sup 0/C) in which whey permeate was hydrolyzed to a degree of hydrolysis of 82% minimum. Enzyme recuperation amounted to 96.5% per batch, all enzyme activity loss being due to thermal inactivation. Microbiological examination of the enzymatic membrane reactor showed that growth of mcicroorganisms can largely be suppressed by working at lower temperature (5/sup 0/C). Eventually, 50 ppm H/sub 2/O/sub 2/ or sterile filtration will adequately solve microbiological problems without affecting enzyme activity.

  11. Effect of hydrolysis enzymatic process of corn using protease crude (Rhizopus oligosporus-C1) to produce corn hydrolisate rich folic acid

    Science.gov (United States)

    Maryati, Yati; Susilowati, Agustine; Melanie, Hakiki; Lotulung, Puspa D.

    2017-11-01

    Corn hydrolyzate (Zea mays L) as a functional food fortificant derived from natural folic acid has been evaluated through a hydrolysis process using protease enzyme Rhizopus oligosporus strain C1. Enzymatic hydrolysis was carried out on two types of corn; yellow and white pearl variety corn, at concentration of protease enzyme (rough) 0.025; 0.125; and 0.225% (v/w of soluble nixtamal corn protein) with a hydrolysis time of 24 h at 30 °C, and pH 5.0. The results showed that the concentration of protease enzymes can increase the folic acid to the optimum condition, from the beginning to the end of the process time. Folic acid optimization of hydrolysis results in each corn was at the concentration of protease enzyme 0.225% (v/w of soluble nixtamal corn protein) in white corn and yellow corn at 24 hours hydrolysis, with folic acid composition, 283.56 µg/mL and 412.52 µg/mL, 1.07 and 1.04 mg/mL of soluble proteins, proteolytic activity 2.09 and 2.06 U/mL, total solids of 21.74 and 17.85%, total sugars of 0.56 and 2.22 mg/mL, and reducing sugar 91.72 and 48.47 mg/mL. In this condition, the increase of optimum folic acid for white corn was 33.57% and for yellow corn was 71.60% after hydrolysis.

  12. Enzymatic hydrolysis of biomimetic bacterial cellulose-hemicellulose composites.

    Science.gov (United States)

    Penttilä, Paavo A; Imai, Tomoya; Hemming, Jarl; Willför, Stefan; Sugiyama, Junji

    2018-06-15

    The production of biofuels and other chemicals from lignocellulosic biomass is limited by the inefficiency of enzymatic hydrolysis. Here a biomimetic composite material consisting of bacterial cellulose and wood-based hemicelluloses was used to study the effects of hemicelluloses on the enzymatic hydrolysis with a commercial cellulase mixture. Bacterial cellulose synthesized in the presence of hemicelluloses, especially xylan, was found to be more susceptible to enzymatic hydrolysis than hemicellulose-free bacterial cellulose. The reason for the easier hydrolysis could be related to the nanoscale structure of the substrate, particularly the packing of cellulose microfibrils into ribbons or bundles. In addition, small-angle X-ray scattering was used to show that the average nanoscale morphology of bacterial cellulose remained unchanged during the enzymatic hydrolysis. The reported easier enzymatic hydrolysis of bacterial cellulose produced in the presence of wood-based xylan offers new insights to overcome biomass recalcitrance through genetic engineering. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. Enzymatic hydrolysis and fermentation of agricultural residues to ethanol

    Energy Technology Data Exchange (ETDEWEB)

    Mes-Hartree, M.; Hogan, C.M.; Saddler, J.N.

    1984-01-01

    A combined enzymatic hydrolysis and fermentation process was used to convert steam-treated wheat and barley straw to ethanol. Maximum conversion efficiencies were obtained when the substrates were steamed for 90 s. These substrates could yield over 0.4 g ethanol/g cellulose following a combined enzymatic hydrolysis and fermentation process procedure using culture filtrates derived from Trichoderma harzianum E58. When culture filtrates from Trichoderma reesei C30 and T. reesei QM9414 were used, the ethanol yields obtained were 0.32 and 0.12 g ethanol/g cellulose utilized, respectively. The lower ethanol yields obtained with these strains were attributed to the lower amounts of ..beta..-glucosidase detected in the T. reesei culture filtrates.

  14. Novel DDR Processing of Corn Stover Achieves High Monomeric Sugar Concentrations from Enzymatic Hydrolysis (230 g/L) and High Ethanol Concentration (10% v/v) During Fermentation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiaowen; Jennings, Ed; Shekiro, Joe; Kuhn, Erik M.; O' Brien, Marykate; Wang, Wei; Schell, Daniel J.; Himmel, Mike; Elander, Richard T.; Tucker, Melvin P.

    2015-04-03

    Distilling and purifying ethanol, butanol, and other products from second and later generation lignocellulosic biorefineries adds significant capital and operating cost for biofuels production. The energy costs associated with distillation affects plant gate and life cycle analysis costs. Lower titers in fermentation due to lower sugar concentrations from pretreatment increase both energy and production costs. In addition, higher titers decrease the volumes required for enzymatic hydrolysis and fermentation vessels. Therefore, increasing biofuels titers has been a research focus in renewable biofuels production for several decades. In this work, we achieved over 200 g/L of monomeric sugars after high solids enzymatic hydrolysis using the novel deacetylation and disc refining (DDR) process on corn stover. The high sugar concentrations and low chemical inhibitor concentrations from the DDR process allowed ethanol titers as high as 82 g/L in 22 hours, which translates into approximately 10 vol% ethanol. To our knowledge, this is the first time that 10 vol% ethanol in fermentation derived from corn stover without any sugar concentration or purification steps has been reported. Techno-economic analysis shows the higher titer ethanol achieved from the DDR process could significantly reduce the minimum ethanol selling price from cellulosic biomass.

  15. PRETREATMENT OF LIGNOCELLULOSIC BIOMASS FOR ENZYMATIC HYDROLYSIS

    Directory of Open Access Journals (Sweden)

    Doan Thai Hoa

    2017-11-01

    Full Text Available The cost of raw materials continues to be a limiting factor in the production of bio-ethanol from traditional raw materials, such as sugar and starch. At the same time, there are large amount of agricultural residues as well as industrial wastes that are of low or negative value (due to costs of current effluent disposal methods. Dilute sulfuric acid pretreatment of elephant grass and wood residues for the enzymatic hydrolysis of cellulose has been investigated in this study.    Elephant grass (agricultural residue and sawdust (Pulp and Paper Industry waste with a small particulate size were treated using different dilute sulfuric acid concentrations at a temperature  of 140-170°C within 0.5-3 hours. The appropriate pretreatment conditions give the highest yield of soluble saccharides and total reducing sugars.

  16. Radiation degradation and the subsequent enzymatic hydrolysis of waste paper

    International Nuclear Information System (INIS)

    Kamakura, M.; Kaetsu, I.

    1982-01-01

    Various studies have been carried out to find methods for the pretreatment of waste cellulosic materials to make them more susceptible to enzymatic hydrolysis. In the work reported here, the effects of preirradiating waste papers on subsequent enzymatic hydrolysis have been studied

  17. DEXTRINIZED SYRUPS OBTAINING THROUGH THE ENZYMATIC HYDROLYSIS OF SORGHUM STARCH

    Directory of Open Access Journals (Sweden)

    Leyanis Rodríguez Rodríguez

    2015-10-01

    Full Text Available The main objective of this work was the production of syrups dextrinized by enzymatic hydrolysis of starch red sorghum CIAPR-132 using α-amylase on solutions at different concentrations, with different concentrations of enzyme and enzyme hydrolysis time. The response variable was the dextrose equivalent in each obtained syrup (ED using the modified Lane-Eynon method. In some of the experiments, we used a full factorial design 23 and in others we worked with intermediate concentration and higher hydrolysis time with different levels of enzyme. The obtained products were syrups dextrinized ED between 10,25 and 33,97% (values we can find within the established ones for these types of syrups, which can be used for their functional properties as intermediates syrups or as raw material for different processes of the food industry. This allows you to set a pattern for the use of sorghum feedstock in unconventional obtaining products from its starch.

  18. Short-time ultrasonication treatment in enzymatic hydrolysis of biomass

    Science.gov (United States)

    Zengqian Shi; Zhiyong Cai; Siqun Wang; Qixin Zhong; Joseph J. Bozell

    2013-01-01

    To improve the conversion of enzymatic hydrolysis of biomass in an energy-efficient manner, two shorttime ultrasonication strategies were applied on six types of biomass with different structures and components. The strategies include pre-sonication before the hydrolysis and intermittent sonication during the ongoing hydrolysis. The microstructures of each type of...

  19. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk

    Directory of Open Access Journals (Sweden)

    Rudy Agustriyanto

    2012-12-01

    Full Text Available Coconut husk is classified as complex lignocellulosic material that contains cellulose, hemicellulose, lignin, and some other extractive compounds. Cellulose from coconut husk can be used as fermentation substrate after enzymatic hydrolysis. In contrary, lignin content from the coconut husk will act as an inhibitor in this hydrolysis process. Therefore, a pretreatment process is needed to enhance the hydrolysis of cellulose. The objective of this research is to investigate the production of the glucose through dilute acid pretreatment and to obtain its optimum operating conditions. In this study, the pretreatment was done using dilute sulfuric acid in an autoclave reactor. The pretreatment condition were varied at 80°C, 100°C, 120°C and 0.9%, 1.2%, 1.5% for temperature and acid concentration respectively. The acid pretreated coconut husk was then hydrolyzed using commercial cellulase (celluclast and β-glucosidase (Novozyme 188. The hydrolysis time was 72 hours and the operating conditions were varied at several temperature and pH. From the experimental results it can be concluded that the delignification temperature variation has greater influence than the acid concentration. The optimum operating condition was obtained at pH 4 and 50°C which was pretreated at 100°C using 1.5% acid concentration. Copyright © 2012 by BCREC UNDIP. All rights reserved. (Selected Paper from International Conference on Chemical and Material Engineering (ICCME 2012Received: 28th September 2012, Revised: 2nd October 2012, Accepted: 4th October 2012[How to Cite: R. Agustriyanto, A. Fatmawati, Y. Liasari. (2012. Study of Enzymatic Hydrolysis of Dilute Acid Pretreated Coconut Husk. Bulletin of Chemical Reaction Engineering & Catalysis, 7(2: 137-141. doi:10.9767/bcrec.7.2.4046.137-141] [How to Link / DOI: http://dx.doi.org/10.9767/bcrec.7.2.4046.137-141 ] | View in 

  20. Kinetics of enzymatic hydrolysis of methyl ricinoleate

    Directory of Open Access Journals (Sweden)

    Neeharika, T. S.V.R.

    2015-12-01

    Full Text Available Ricinoleic acid is an unsaturated hydroxy fatty acid that naturally occurs in castor oil in proportions of up to 85–90%. Ricinoleic acid is a potential raw material and finds several applications in coatings, lubricant formulations and pharmaceutical areas. Enzymatic hydrolysis of castor oil is preferred over conventional hydrolysis for the preparation of ricinoleic acid to avoid estolide formation. A kinetics analysis of the enzymatic hydrolysis of Methyl Ricinoleate in the presence of Candida antarctica Lipase B was carried out in this study by varying reaction temperature (40–60 °C and enzyme concentration (2–5%. The optimal conditions were found to be 6 h reaction time, temperature 60°C, buffer to methyl ricinoleate ratio 2:1(v/w and 4% enzyme concentration to achieve a maximum conversion of 98.5%. A first order reversible reaction kinetic model was proposed to describe this reaction and a good agreement was observed between the experimental data and the model values. The effect of temperature on the forward reaction rate constant was determined by fitting data to the Arrhenius equation. The activation energy for forward reaction was found to be 14.69 KJ·mol−1.El ácido ricinoleico es un hidroxiácido insaturado que se produce naturalmente en el aceite de ricino en proporciones de hasta el 85–90%. El ácido ricinoleico es una materia prima con gran potencial y tiene aplicaciones en revestimientos, formulaciones lubricantes y en áreas farmacéuticas. Para la preparación del ácido ricinoleico se prefiere la hidrólisis enzimática del aceite de ricino a la hidrólisis convencional, para evitar la formación de estólidos. En este estudio se llevó a cabo la cinética de la hidrólisis enzimática del ricinoleato de metilo en presencia de lipasa de Candida antarctica B mediante la variación de la temperatura de reacción (40–60 °C y la concentración de la enzima (2–5%. Las condiciones óptimas de la reacción para

  1. Enzymatic activity of the cellulolytic complex produced by trichoderma reesei. Enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Alfonsel Jaen, M.; Negro, M.J.; Saez, R.; Martin Moreno, C.

    1986-01-01

    The enzymatic activity characterization of the cellulolytic complex obtained from Trichoderma reese QM 9414 and the influence of the enzymatic hydrolysis conditions on the hydrolysis yield are studied. Pure cellulose and native or alkali pretreated biomass from Onopordum nervosum have been used as substrates. The values of pH, temperature, substrate concentration and enzyme-substrate ratio for the optimum activity of that complex, evaluated as glucose and reducing sugars productions, have been selected. Previous studies on enzymatic hydrolysis of O. nervosum have shown a remarkable effect of the alkaline pretreatments on the final hydrolysis yield. (author). 10 figs.; 10 refs

  2. Enzymatic activity of the cellulolytic complex produced by Trichoderma reesei. Enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Alfonsel J, M.; Negro A, M. J.; Saez A, R.; Martin M, C.

    1986-01-01

    The enzymatic activity characterization of the cellulolytic complex obtained from Trichoderma reesei QM 9414 and the influence of the enzymatic hydrolysis conditions on the hydrolysis yield are studied. Pure cellulose and native or alkali pretreated biomass Onopordum nervosum have been used as substrates. The values of pH, temperature, substrate concentration and enzyme-substrate ratio for the optimum activity of that complex, evaluated as glucose and reducing sugars production, have been selected. Previous studies on enzymatic hydrolysis of 0. nervosum have shown a remarkable effect of the alkaline pretreatments on the final hydrolysis yield. (Author) 10 refs

  3. Numerical prediction of kinetic model for enzymatic hydrolysis of cellulose using DAE-QMOM approach

    Science.gov (United States)

    Jamil, N. M.; Wang, Q.

    2016-06-01

    Bioethanol production from lignocellulosic biomass consists of three fundamental processes; pre-treatment, enzymatic hydrolysis, and fermentation. In enzymatic hydrolysis phase, the enzymes break the cellulose chains into sugar in the form of cellobiose or glucose. A currently proposed kinetic model for enzymatic hydrolysis of cellulose that uses population balance equation (PBE) mechanism was studied. The complexity of the model due to integrodifferential equations makes it difficult to find the analytical solution. Therefore, we solved the full model of PBE numerically by using DAE-QMOM approach. The computation was carried out using MATLAB software. The numerical results were compared to the asymptotic solution developed in the author's previous paper and the results of Griggs et al. Besides confirming the findings were consistent with those references, some significant characteristics were also captured. The PBE model for enzymatic hydrolysis process can be solved using DAE-QMOM method. Also, an improved understanding of the physical insights of the model was achieved.

  4. Progressing batch hydrolysis process

    Science.gov (United States)

    Wright, J.D.

    1985-01-10

    A progressive batch hydrolysis process is disclosed for producing sugar from a lignocellulosic feedstock. It comprises passing a stream of dilute acid serially through a plurality of percolation hydrolysis reactors charged with feed stock, at a flow rate, temperature and pressure sufficient to substantially convert all the cellulose component of the feed stock to glucose. The cooled dilute acid stream containing glucose, after exiting the last percolation hydrolysis reactor, serially fed through a plurality of pre-hydrolysis percolation reactors, charged with said feedstock, at a flow rate, temperature and pressure sufficient to substantially convert all the hemicellulose component of said feedstock to glucose. The dilute acid stream containing glucose is cooled after it exits the last prehydrolysis reactor.

  5. Enzymatic hydrolysis of corn bran arabinoxylan

    DEFF Research Database (Denmark)

    Agger, Jane

    as a model substrate because it represents a readily available agroindustrial side product with upgrading potentials. Corn bran originates from the wet-milling process in corn starch processing, is the outmost layers of the corn kernel and is particularly rich in pentose monosaccharides comprising the major...... in a complex and ridig cell wall structure. This thesis contains a thorough examination of the monosaccharide and structural composition of corn bran, which is used to assess and apply the relevant mono component enzyme preparations. In this way, the aim is to obtain the most effective minimal enzymatic......, especially with respect to xylose and glucose release, but vast amounts of the valuable monosaccharides are lost during this pretreatment and this is especially evident for arabinose. From a scientific point of view acid catalysed pretreatment renders the substrate in a state of disruption where assessment...

  6. Glucose obtained from rice bran by ultrasound-assisted enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Raquel Cristine Kuhn

    2015-05-01

    Full Text Available In this work ultrasound-assisted solid-state enzymatic hydrolysis of rice bran to obtain fermentable sugars was investigated. For this purpose, process variables such as temperature, enzyme concentration and moisture content were evaluated during the enzymatic hydrolysis with and without ultrasound irradiation. The enzyme used is a blend of amylases derived from genetically modified strains of Trichoderma reesei. Kinetic of the enzymatic hydrolysis of rice bran at the constant-reaction rate period were measured. The best results for the ultrasound-assisted enzymatic hydrolysis was obtained using 3 wt% of enzyme, 60 oC and moisture content of 65 wt%, yielding 0.38 g sugar/g rice bran, whereas for the hydrolysis in the absence of ultrasound the highest yield was 0.20 g sugar/g rice bran using 3 wt% of enzyme, 60 oC and moisture content of 50 wt%. The use of ultrasound-assisted enzymatic hydrolysis of rice bran was intensified, obtaining around 74% more fermentable sugar than in the absence, showing that the use of ultrasound is a promising technology to be used in enzymatic reaction as an alternative of process intensification.

  7. Enzymatic hydrolysis of biomass at high-solids loadings – A review

    International Nuclear Information System (INIS)

    Modenbach, Alicia A.; Nokes, Sue E.

    2013-01-01

    Enzymatic hydrolysis is the unit operation in the lignocellulose conversion process that utilizes enzymes to depolymerize lignocellulosic biomass. The saccharide components released are the feedstock for fermentation. When performed at high-solids loadings (≥15% solids, w/w), enzymatic hydrolysis potentially offers many advantages over conversions performed at low- or moderate-solids loadings, including increased sugar and ethanol concentrations and decreased capital and operating costs. The goal of this review is to provide a consolidated source of information on studies using high-solids loadings in enzymatic hydrolysis. Included in this review is a brief discussion of the limitations, such as a lack of available water, difficulty with mixing and handling, insufficient mass and heat transfer, and increased concentration of inhibitors, associated with the use of high solids, as well as descriptions and findings of studies that performed enzymatic hydrolysis at high-solids loadings. Reactors designed and/or equipped for improved handling of high-solids slurries are also discussed. Lastly, this review includes a brief discussion of some of the operations that have successfully scaled-up and implemented high-solids enzymatic hydrolysis at pilot- and demonstration-scale facilities. -- Highlights: •High solids enzymatic hydrolysis needed for conversion process to be cost-effective. •Limitations must be addressed before benefits of high-solid loadings fully realized. •Some success with high-solids loadings at pilot and demonstration scale

  8. Production of xylooligosaccharide from wheat bran by microwave assisted enzymatic hydrolysis.

    Science.gov (United States)

    Wang, Tseng-Hsing; Lu, Shin

    2013-06-01

    The effective production of xylooligosaccharides (XOS) from wheat bran was investigated. Wheat bran contains rich hemicellulose which can be hydrolyzed by enzyme; the XOS were obtained by microwave assisted enzymatic hydrolysis. To improve the productivity of XOS, repeated microwave assisted enzymatic hydrolysis and activated carbon adsorption method was chosen to eliminate macromolecules in the XOS. On the basis of experimental data, an industrial XOS production process consisting of pretreatment, repeated microwave assisted enzymatic treatment and purification was designed. Using the designed process, 3.2g dry of purified XOS was produced from 50 g dry wheat bran powder. Copyright © 2012 Elsevier Ltd. All rights reserved.

  9. Optimum yields of dibenzylbutyrolactone-type lignans from Cynareae fruits, during their ripening, germination and enzymatic hydrolysis processes, determined by on-line chromatographic methods.

    Science.gov (United States)

    Szokol-Borsodi, Lilla; Sólyomváry, Anna; Molnár-Perl, Ibolya; Boldizsár, Imre

    2012-01-01

    Dibenzylbutyrolactone-type lignans are the physiologically active constituents of the achene fruits of Cynareae. These lignans occur in glycoside/aglycone forms: in the highest quantity of the arctiin/arctigenin, matairesinoside/matairesinol and tracheloside/trachelogenin pairs found in the fruits of Arctium lappa L., Centaurea scabiosa L. and Cirsium arvense (L.) Scop. To optimise the extraction yield of the arctiin/arctigenin, matairesinoside/matairesinol and tracheloside/trachelogenin glycoside/aglycone pairs, from the fruits of Arctium lappa, Centaurea scabiosa and Cirsium arvense, under the ripening, germination and enzymatic hydrolysis processes of the fruits. Identification and quantification of lignans were performed with on-line gas chromatography-mass spectrometry (GC-MS) and with high performance liquid chromatography (HPLC), both with UV and mass selective detections (HPLC-UV/MS). As novelties to the field it was confirmed that: (i) the unripe fruits provide a high amount of lignans, similar to the ripe fruit; (ii) the fruits of Arctium lappa and Cirsium arvense do have glycosidase activity to hydrolyse their lignan glycosides into free lignans; (iii) the glycosidase of Centaurea scabiosa fruit becomes activated under its germination process only; and (iv) the overwhelming part of the fruits lignan contents (80-94%) in all three species are accumulated in the embryo. The best sources of (i) lignan aglycones are the enzyme-hydrolysed embryos, separating spontaneously during the germination process, and (ii) lignan glycosides are the unripe fruits. Copyright © 2012 John Wiley & Sons, Ltd.

  10. Acid and enzymatic hydrolysis to recover reducing sugars from cassava bagasse: an economic study

    Directory of Open Access Journals (Sweden)

    Woiciechowski Adenise Lorenci

    2002-01-01

    Full Text Available The objective of this work was to study the acid and enzymatic hydrolysis of cassava bagasse for the recovery of reducing sugars and to establish the operational costs. A statistical program "Statistica", based on the surface response was used to optimize the recovery of reducing sugars in both the processes. The process economics was determined considering the values of reducing sugars obtained at laboratory scale, and the operations costs of a cylindrical reactor of 1500 L, with flat walls at the top and bottom. The reactor was operated with 150 kg of cassava bagasse and 1350 kg of water. The yield of the acid hydrolysis was 62.4 g of reducing sugars from 100 g of cassava bagasse containing 66% starch. It represented 94.5% of reducing sugar recovery. The yield of the enzymatic hydrolysis was 77.1 g of reducing sugars from 120 g of cassava bagasse, which represented 97.3% of reducing sugars recovery. Concerning to the time, a batch of acid hydrolysis required 10 minutes, plus the time to heat and cool the reactor, and a batch of the enzymatic hydrolysis needed 25 hours and 20 minutes, plus the time to heat and to cool the reactor. Thus, the acid hydrolysis of 150 kg of cassava bagasse required US$ 34.27, and the enzymatic hydrolysis of the same amount of cassava bagasse required US$ 2470.99.

  11. Pretreatment of sugarcane bagasse using the advanced oxidation process by electron beam for enzymatic hydrolysis of cellulose; Pre-tratamento do bagaco de cana utilizando o processo de oxidacao avancada por feixe de eletrons para hidrolise enzimatica da celulose

    Energy Technology Data Exchange (ETDEWEB)

    Ribeiro, Marcia Almeida

    2013-07-01

    The sugar cane bagasse is a renewable energy source and a raw material promise in the biofuel production, once represents about 30% of glucose contained in the plant with the potential to be hydrolyzed and then converted to ethanol. The bagasse is composed of cellulose, straight chain of glucose, of hemicellulose, an amorphous polymer consisting of xylose, arabinose, galactose, and mannose, and of lignin, a complex polymer consisting of fenilpropan units that acts as waterproof coating on the fibers, which is hard to remove due its recalcitrant nature. The aim of this work was to study the electron beam processing as a pretreatment of sugarcane bagasse to enzymatic hydrolysis of cellulose. The pretreatment of sugarcane bagasse is one of the most important steps to make this material economically viable and competitive on the energy production. As a pretreatment the electron beam processing can weak the hemicellulose and lignin structures by the action highly reactive radicals that breaks the links, reducing the degree of polymerization fibers. It was evaluated the chemical and structural modifications on fibers caused by the irradiation, the enzymatic hydrolysis of electron beam as the only pretreatment and combined to steam explosion. For enzymatic hydrolysis it was used the commercial enzymes from Novozymes. The radiation processing promotes changes in structure and composition of sugarcane bagasse, increasing the solubility, that is related to hemicellulose and cellulose cleavage, and also increasing the enzymatic conversion yield. In the case of exploded bagasse there is no changes in the enzymatic hydrolysis yield, however the electron beam processing promoted a 67% reduction of furfural, that is formed in the steam explosion process. (author)

  12. Evaluation of wet oxidation pretreatment for enzymatic hydrolysis of softwood

    DEFF Research Database (Denmark)

    Palonen, H.; Thomsen, A.B.; Tenkanen, M.

    2004-01-01

    The wet oxidation pretreatment (water, oxygen, elevated temperature, and pressure) of softwood (Picea abies) was investigated for enhancing enzymatic hydrolysis. The pretreatment was preliminarily optimized. Six different combinations of reaction time, temperature, and pH were applied......, and the compositions of solid and liquid fractions were analyzed. The solid fraction after wet oxidation contained 58-64% cellulose, 2-16% hemicellulose, and 24-30% lignin. The pretreatment series gave information about the roles of lignin and hemicellulose in the enzymatic hydrolysis. The temperature...

  13. Process Design Report for Wood Feedstock: Lignocellulosic Biomass to Ethanol Process Desing and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Wooley, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ruth, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sheehan, John [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibsen, Kelly [National Renewable Energy Lab. (NREL), Golden, CO (United States); Majdeski, Henry [Delta-T Corporation, Lexington, KY (United States); Galves, Adrian [Delta-T Corporation, Lexington, KY (United States)

    1999-07-01

    The National Renewable Energy Laboratory (NREL) has undertaken a complete review and update of the process design and economic model for the biomass-to-ethanol process based on co-current dilute acid prehydrolysis, along with simultaneous saccharification (enzymatic) and co-fermentation. The process design includes the core technologies being researched by the U.S. Department of Energy (DOE): prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production.

  14. Radiation degration and the subsequent enzymatic hydrolysis of waste papers

    International Nuclear Information System (INIS)

    Kamakura, M.; Kaetsu, I.

    1982-01-01

    In recent years, many methods have been proposed for the hydrolysis of waste cellulose to utilize it as a new source of alcohol. Because it is difficult to hydrolyze waste cellulosic materials effectivley with an enzyme, the effects of preirradiating waste papers on subsequent enzymatic hydrolysis was studied. Preirradiation (x rays from 60 Co) accelerated the hydrolysis rate of newspaper by cellulase and the reducing-sugar yield increased with increasing irradiation dose. It is thought that preirradiation probably contributes to loosening and releasing the compactly entangled structure of cellulose and lignin in the materials by radiation degradation

  15. Increased release of fermentable sugars from elephant grass by enzymatic hydrolysis in the presence of surfactants

    International Nuclear Information System (INIS)

    Menegol, Daiane; Scholl, Angélica Luisi; Fontana, Roselei Claudete; Dillon, Aldo José Pinheiro; Camassola, Marli

    2014-01-01

    Highlights: • Milling is an attractive method to enhance the enzymatic hydrolysis of biomass. • Surfactants improve the efficiency of lignocellulose enzymatic hydrolysis. • Pretreatment with NaOH, smaller particle size and Tween 80® were more efficient. - Abstract: In the search for renewable energy sources, elephant grass is an alternative substrate for ethanol production, but this substrate must be hydrolyzed by cellulases and xylanases to liberate fermentable sugars. During enzymatic hydrolysis, cellulase activity is reduced by the irreversible adsorption of cellulase onto cellulose, decreasing the rate of hydrolysis. Adding surfactants during hydrolysis can improve the process. The effects of Tween® and Triton® surfactants on the enzymatic hydrolysis of elephant grass were evaluated in this context. The data indicate that pretreatment with sodium hydroxide, along with a smaller particle size (0.075–0.152 mm) and the use of Tween 80®, increased the efficiency of releasing reducing sugars from pretreated elephant grass biomass. Thus, it is possible to reduce grinding costs in second-generation ethanol production through the use of surfactants, as they allow efficient hydrolysis of larger biomass particles

  16. Comparison of the economics of acid and enzymatic hydrolysis of newsprint

    Energy Technology Data Exchange (ETDEWEB)

    Grethlein, H E

    1978-04-01

    In order to compare the process economics of making glucose from cellulose, a plant design is presented using acid hydrolysis which can be compared with a published design using enzyme hydrolysis. A common design basis is used; namely, an input capacity of 885 ton/day newsprint with a common technique of cost estimation. The cost of making glucose is in the range of 1.75 to 2.45 cents/lb, depending on the slurry concentration fed to the reactor for the acid hydrolysis. This cost range is less than the published estimate of 5.2 cents/lb for enzymatic hydrolysis.

  17. Beam irradiation pretreatment on enzymatic hydrolysis of biomass

    International Nuclear Information System (INIS)

    Yoo, Hah Young; Choi, Han Suk; Yang, Soo Jeong; Lee, Ja Hyun; Kim, Sung Bong; Jung, Da Un; Kim, Seung Wook

    2013-01-01

    As a renewable energy resource, lignocellulosic biomass has become great attention these days. Miscanthus is considered as one of the best feed stock for sugar production due to its high carbohydrate conversion, more efficient pretreatment process was necessary for removal of enzymatic hydrolysis barriers. In this study, electron beam irradiation pretreatment was utilized to Miscanthus straw for the enhancement of sugar conversion. The prepared samples were exposed 20 ∼ 500 kGy of doses and 5 ∼ 100 kGy of dose rate under 1 MeV of energy. Optimum irradiation conditions were 300 kGy of doses, 10 kGy of doses rate and 7.4 mA of current. Finally, compared with untreated Miscanthus, the glucose conversion was 2 fold increased under optimal conditions

  18. Wet explosion pretreatment of sugarcane bagasse for enhanced enzymatic hydrolysis

    DEFF Research Database (Denmark)

    Biswas, Rajib; Uellendahl, Hinrich; Ahring, Birgitte Kiær

    2014-01-01

    .7% of the theoretical maximum value. Pretreatment at 200 C with oxygen exhibited enhanced enzymatic efficiency but lower xylose recovery and formation of the degradation products such as acetate, furfural and HMF of 7.6, 3.3 and 1.0 g/L, respectively. In the hydrolysis, the total sugars (glucose + xylose) yielded...

  19. Cellulase-lignin interactions in the enzymatic hydrolysis of lignocellulose

    Energy Technology Data Exchange (ETDEWEB)

    Rahikainen, J.

    2013-11-01

    Today, the production of transportation fuels and chemicals is heavily dependent on fossil carbon sources, such as oil and natural gas. Their limited availability and the environmental concerns arising from their use have driven the search for renewable alternatives. Lignocellulosic plant biomass is the most abundant, but currently underutilised, renewable carbon-rich resource for fuel and chemical production. Enzymatic degradation of structural polysaccharides in lignocellulose produces soluble carbohydrates that serve as ideal precursors for the production of a vast amount of different chemical compounds. The difficulty in full exploitation of lignocellulose for fuel and chemical production lies in the complex and recalcitrant structure of the raw material. Lignocellulose is mainly composed of structural polysaccharides, cellulose and hemicellulose, but also of lignin, which is an aromatic polymer. Enzymatic degradation of cellulose and hemicellulose is restricted by several substrate- and enzyme-related factors, among which lignin is considered as one of the most problematic issues. Lignin restricts the action of hydrolytic enzymes and enzyme binding onto lignin has been identified as a major inhibitory mechanism preventing efficient hydrolysis of lignocellulosic feedstocks. In this thesis, the interactions between cellulase enzymes and lignin-rich compounds were studied in detail and the findings reported in this work have the potential to help in controlling the harmful cellulase-lignin interactions, and thus improve the biochemical processing route from lignocellulose to fuels and chemicals.

  20. Combined subcritical water and enzymatic hydrolysis for reducing sugar production from coconut husk

    Science.gov (United States)

    Muharja, Maktum; Junianti, Fitri; Nurtono, Tantular; Widjaja, Arief

    2017-05-01

    Coconut husk wastes are abundantly available in Indonesia. It has a potential to be used into alternative renewable energy sources such as hydrogen using enzymatic hydrolysis followed by a fermentation process. Unfortunately, enzymatic hydrolysis is hampered by the complex structure of lignocellulose, so the cellulose component is hard to degrade. In this study, Combined Subcritical Water (SCW) and enzymatic hydrolysis are applied to enhance fermentable, thereby reducing production of sugar from coconut husk. There were two steps in this study, the first step was coconut husk pretreated by SCW in batch reactor at 80 bar and 150-200°C for 60 minutes reaction time. Secondly, solid fraction from the results of SCW was hydrolyzed using the mixture of pure cellulose and xylanase enzymes. Analysis was conducted on untreated and SCW-treated by gravimetric assay, liquid fraction after SCW and solid fraction after enzymatic hydrolysis using DNS assay. The maximum yield of reducing sugar (including xylose, arabinose glucose, galactose, mannose) was 1.254 gr per 6 gr raw material, representing 53.95% of total sugar in coconut husk biomass which was obtained at 150°C 80 bar for 60 minutes reaction time of SCW-treated and 6 hour of enzymatic hydrolysis using mixture of pure cellulose and xylanase enzymes (18.6 U /gram of coconut husk).

  1. Continuous enzymatic hydrolysis of lignocellulosic biomass with simultaneous detoxification and enzyme recovery.

    Science.gov (United States)

    Gurram, Raghu N; Menkhaus, Todd J

    2014-07-01

    Recovering hydrolysis enzymes and/or alternative enzyme addition strategies are two potential mechanisms for reducing the cost during the biochemical conversion of lignocellulosic materials into renewable biofuels and biochemicals. Here, we show that enzymatic hydrolysis of acid-pretreated pine wood with continuous and/or fed-batch enzyme addition improved sugar conversion efficiencies by over sixfold. In addition, specific activity of the hydrolysis enzymes (cellulases, hemicellulases, etc.) increased as a result of continuously washing the residual solids with removal of glucose (avoiding the end product inhibition) and other enzymatic inhibitory compounds (e.g., furfural, hydroxymethyl furfural, organic acids, and phenolics). As part of the continuous hydrolysis, anion exchange resin was tested for its dual application of simultaneous enzyme recovery and removal of potential enzymatic and fermentation inhibitors. Amberlite IRA-96 showed favorable adsorption profiles of inhibitors, especially furfural, hydroxymethyl furfural, and acetic acid with low affinity toward sugars. Affinity of hydrolysis enzymes to adsorb onto the resin allowed for up to 92 % of the enzymatic activity to be recovered using a relatively low-molar NaCl wash solution. Integration of an ion exchange column with enzyme recovery into the proposed fed-batch hydrolysis process can improve the overall biorefinery efficiency and can greatly reduce the production costs of lignocellulosic biorenewable products.

  2. Evaluation of physical structural features on influencing enzymatic hydrolysis efficiency of micronized wood

    Science.gov (United States)

    Jinxue Jiang; Jinwu Wang; Xiao Zhang; Michael Wolcott

    2016-01-01

    Enzymatic hydrolysis of lignocellulosic biomass is highly dependent on the changes in structural features after pretreatment. Mechanical milling pretreatment is an effective approach to alter the physical structure of biomass and thus improve enzymatic hydrolysis. This study examined the influence of structural characteristics on the enzymatic hydrolysis of micronized...

  3. Hydrothermal pretreatment and enzymatic hydrolysis of mixed green and woody lignocellulosics from arid regions

    DEFF Research Database (Denmark)

    Ashraf, Muhammad Tahir; Thomsen, Mette Hedegaard; Schmidt, Jens Ejbye

    2017-01-01

    Utilization of multi-specie feedstocks is imperative for application of lignocellulosic biorefineries in arid regions. Different lignocellulosic residues vary in composition and anatomical features. Pretreatment and enzymatic hydrolysis are two processes at the front end of any lignocellulosics...... biorefinery applying biochemical pathway, and have to efficiently deal with the variance in the feedstock composition and properties. However, there is limited knowledge about effect of mixing different lignocellulosics on pretreatment and enzymatic hydrolysis yields. In this study effect of mixing...... on the yields from hydrothermal pretreatment and enzymatic hydrolysis was analyzed by mixing three different lignocellulosic residues — Bermuda grass, Jasmine hedges, and date palm fronds. Results showed that the individual and the mixed lignocellulosics gave same yields when treated under similar conditions...

  4. Production of xylitol from corn cob hydrolysate through acid and enzymatic hydrolysis by yeast

    Science.gov (United States)

    Mardawati, Efri; Andoyo, R.; Syukra, K. A.; Kresnowati, MTAP; Bindar, Y.

    2018-03-01

    The abundance of corn production in Indonesia offers the potential for its application as the raw material for biorefinery process. The hemicellulose content in corn cobs can be considered to be used as a raw material for xylitol production. The purpose of this research was to study the effect of hydrolysis methods for xylitol production and the effect of the hydrolyzed corn cobs to produce xylitol through fermentation. Hydrolysis methods that would be evaluated were acid and enzymatic hydrolysis. The result showed that the xylitol yield of fermented solution using enzymatic hydrolysates was 0.216 g-xylitol/g-xylose, which was higher than the one that used acid hydrolysates, which was 0.100 g-xylitol/g-xylose. Moreover, the specific growth rate of biomass in fermentation using enzymatic hydrolysates was also higher than the one that used acid hydrolysates, 0.039/h compared to 0.0056/h.

  5. Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling

    Science.gov (United States)

    2013-01-01

    Background It is necessary to develop efficient methods to produce renewable fuels from lignocellulosic biomass. One of the main challenges to the industrialization of lignocellulose conversion processes is the large amount of cellulase enzymes used for the hydrolysis of cellulose. One method for decreasing the amount of enzyme used is to recycle the enzymes. In this study, the recycle of enzymes associated with the insoluble solid fraction after the enzymatic hydrolysis of cellulose was investigated for pretreated corn stover under a variety of recycling conditions. Results It was found that a significant amount of cellulase activity could be recovered by recycling the insoluble biomass fraction, and the enzyme dosage could be decreased by 30% to achieve the same glucose yields under the most favorable conditions. Enzyme productivity (g glucose produced/g enzyme applied) increased between 30 and 50% by the recycling, depending on the reaction conditions. While increasing the amount of solids recycled increased process performance, the methods applicability was limited by its positive correlation with increasing total solids concentrations, reaction volumes, and lignin content of the insoluble residue. However, increasing amounts of lignin rich residue during the recycle did not negatively impact glucose yields. Conclusions To take advantage of this effect, the amount of solids recycled should be maximized, based on a given processes ability to deal with higher solids concentrations and volumes. Recycling of enzymes by recycling the insoluble solids fraction was thus shown to be an effective method to decrease enzyme usage, and research should be continued for its industrial application. PMID:23336604

  6. Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling

    Directory of Open Access Journals (Sweden)

    Weiss Noah

    2013-01-01

    Full Text Available Abstract Background It is necessary to develop efficient methods to produce renewable fuels from lignocellulosic biomass. One of the main challenges to the industrialization of lignocellulose conversion processes is the large amount of cellulase enzymes used for the hydrolysis of cellulose. One method for decreasing the amount of enzyme used is to recycle the enzymes. In this study, the recycle of enzymes associated with the insoluble solid fraction after the enzymatic hydrolysis of cellulose was investigated for pretreated corn stover under a variety of recycling conditions. Results It was found that a significant amount of cellulase activity could be recovered by recycling the insoluble biomass fraction, and the enzyme dosage could be decreased by 30% to achieve the same glucose yields under the most favorable conditions. Enzyme productivity (g glucose produced/g enzyme applied increased between 30 and 50% by the recycling, depending on the reaction conditions. While increasing the amount of solids recycled increased process performance, the methods applicability was limited by its positive correlation with increasing total solids concentrations, reaction volumes, and lignin content of the insoluble residue. However, increasing amounts of lignin rich residue during the recycle did not negatively impact glucose yields. Conclusions To take advantage of this effect, the amount of solids recycled should be maximized, based on a given processes ability to deal with higher solids concentrations and volumes. Recycling of enzymes by recycling the insoluble solids fraction was thus shown to be an effective method to decrease enzyme usage, and research should be continued for its industrial application.

  7. Enzymatic hydrolysis of pretreated barley and wheat straw

    DEFF Research Database (Denmark)

    Rosgaard, Lisa

    2007-01-01

    . The work involved evaluation of 1) possible ways to increase the glucose release from the commercial cellulase product Celluclast by boosting with other enzyme activities to increase the enzymatic hydrolysis, 2) comparing differently pretreated feedstock substrates and 3) evaluating a fed-batch substrate...... mixture resulted in a glucose release corresponding to ~84 % of the glucose release from Celluclast. It was therefore suggested that other enzyme activities than the 4 four main cellulase activities in Celluclast are necessary for optimal hydrolysis of lignocellulose. Even though Celluclast...... is a multicomponent cellulase mixture, there are still possibilities for further improvement in terms of providing the most efficient cellulase mixture for lignocellulose hydrolysis. It was shown that substrates evaluated all had some residual hemicellulose in the solid cellulose fraction after pretreatment...

  8. Kinetic study of enzymatic hydrolysis of potato starch

    Directory of Open Access Journals (Sweden)

    Óscar Fernando Castellanos Domínguez

    2004-01-01

    Full Text Available This article describes the kinetic study of potato starch enzymatic hydrolysis using soluble enzymes (Novo Nordisk. Different assays divided into four groups were used: reaction time (with which it was possible to reduce the 48-72 hour duration reported in the literature to 16 hours with comparable productivity levels; selecting the set of enzymes to be used (different types were evaluated - BAN and Termamyl as alfa-amylases during dextrinisation stage, and AMG, Promozyme and Fungamyl for sacarification reaction- identifying those presenting the best performance during hydrolysis.Reaction conditions were optimised for the process's two stages (destrinisation and sacarification. Enzyme dose, calcium cofactor concentration, pH, temperature and agitation speed were studied for the first stage. Enzyme ratio, pH and agitation speed were studied for sacarification; the latter parameter reported values having no antecedents in the literature (60 rpm and 30 rpm for first and second reactions, respectively. Michaelis Menten kinetics were calculated once conditions had been optimised, varying substrate from 10-50% P/V, obtaining km and Vmax kinetic parameters for each reaction. A kinetic model was found according to local working conditions which was able to explain potato starch conversion to glucose syrup, achieving 96 dextrose equivalents by the end of the reaction, being well within the maximum range reported in the literature (94-98.Laboratory equipment was constructed prior to carrying out assays which was able to reproduce and improve the conditions reported in the literature, making it a useful, reliable tool for use in assays returning good results.

  9. Starch hydrolysis under low water conditions: a conceptual process design

    NARCIS (Netherlands)

    Veen, van der M.E.; Veelaert, S.; Goot, van der A.J.; Boom, R.M.

    2006-01-01

    A process concept is presented for the hydrolysis of starch to glucose in highly concentrated systems. Depending on the moisture content, the process consists of two or three stages. The two-stage process comprises combined thermal and enzymatic liquefaction, followed by enzymatic saccharification.

  10. Recycle of enzymes and substrate following enzymatic hydrolysis of steam-pretreated aspenwood

    Energy Technology Data Exchange (ETDEWEB)

    Mes-Hartree, M.; Hogan, C.M.; Saddler, J.N.

    1987-09-01

    The commercial production of chemicals and fuels from lignocellulosic residues by enzymatic means still requires considerable research on both the technical and economic aspects. Two technical problems that have been identified as requiring further research are the recycle of the enzymes used in hydrolysis and the reuse of the recalcitrant cellulose remaining after incomplete hydrolysis. Enzyme recycle is required to lower the cost of the enzymes, while the reuse of the spent cellulose will lower the feedstock cost. The conversion process studied was a combined enzymatic hydrolysis and fermentation (CHF) procedure that utilized the cellulolytic enzymes derived from the fungus Trichoderma harzianum E58 and the yeast Saccharomyces cerevisiae. The rate and extent of hydrolysis and ethanol production was monitored as was the activity and hydrolytic potential of the enzymes remaining in the filtrate after the hydrolysis period. When a commercial cellulose was used as the substrate for a routine 2-day CHF process, 60% of the original filter paper activity could be recovered. When steam-treated, water-extracted aspenwood was used as the substrate, only 13% of the original filter paper activity was detected after a similar procedure. The combination of 60% spent enzymes with 40% fresh enzymes resulted in the production of 30% less reducing sugars than the original enzyme mixture. Since 100% hydrolysis of the cellulose portion is seldom accomplished in an enzymatic hydrolysis process, the residual cellulose was used as a substrate for the growth of T. harzianum E58 and production of cellulolytic enzymes. The residue remaining after the CHF process was used as a substrate for the production of the cellulolytic enzymes. The production of enzymes from the residue of the Solka Floc hydrolysis was greater than the production of enzymes from the original Solka Floc. (Refs. 14).

  11. Properties important for solid–liquid separations change during the enzymatic hydrolysis of pretreated wheat straw

    DEFF Research Database (Denmark)

    Weiss, Noah Daniel; Felby, Claus; Thygesen, Lisbeth Garbrecht

    2018-01-01

    Objectives The biochemical conversion of lignocellulosic biomass into renewable fuels and chemicals provides new challenges for industrial scale processes. One such process, which has received little attention, but is of great importance for efficient product recovery, is solid–liquid separations......, which may occur both after pretreatment and after the enzymatic hydrolysis steps. Due to the changing nature of the solid biomass during processing, the solid–liquid separation properties of the biomass can also change. The objective of this study was to show the effect of enzymatic hydrolysis...... of cellulose upon the water retention properties of pretreated biomass over the course of the hydrolysis reaction. Results Water retention value measurements, coupled with 1H NMR T2 relaxometry data, showed an increase in water retention and constraint of water by the biomass with increasing levels...

  12. Effect of high hydrostatic pressure on the enzymatic hydrolysis of bovine serum albumin.

    Science.gov (United States)

    De Maria, Serena; Ferrari, Giovanna; Maresca, Paola

    2017-08-01

    The extent of enzymatic proteolysis mainly depends on accessibility of the peptide bonds, which stabilize the protein structure. The high hydrostatic pressure (HHP) process is able to induce, at certain operating conditions, protein displacement, thus suggesting that this technology can be used to modify protein resistance to the enzymatic attack. This work aims at investigating the mechanism of enzymatic hydrolysis assisted by HHP performed under different processing conditions (pressure level, treatment time). Bovine serum albumin was selected for the experiments, solubilized in sodium phosphate buffer (25 mg mL -1 , pH 7.5) with α-chymotrypsin or trypsin (E/S ratio = 1/10) and HPP treatment (100-500 MPa, 15-25 min). HHP treatment enhanced the extent of the hydrolysis reaction of globular proteins, being more effective than conventional hydrolysis. At HHP treatment conditions maximizing the protein unfolding, the hydrolysis degree of proteins was increased as a consequence of the increased exposure of peptide bonds to the attack of proteolytic enzymes. The maximum hydrolysis degree (10% and 7% respectively for the samples hydrolyzed with α-chymotrypsin and trypsin) was observed for the samples processed at 400 MPa for 25 min. At pressure levels higher than 400 MPa the formation of aggregates was likely to occur; thus the degree of hydrolysis decreased. Protein unfolding represents the key factor controlling the efficiency of HHP-assisted hydrolysis treatments. The peptide produced under high pressure showed lower dimensions and a different structure with respect to those of the hydrolysates obtained when the hydrolysis was carried out at atmospheric pressure, thus opening new frontiers of application in food science and nutrition. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  13. Production of fermentable sugars by combined chemo-enzymatic hydrolysis of cellulosic material for bioethanol production

    Directory of Open Access Journals (Sweden)

    M. Idrees

    2014-06-01

    Full Text Available To change the recalcitrant nature of the lignocellulosic material for maximum hydrolysis yield, a comprehensive study was done by using sulphuric acid as an exclusive catalyst for the pretreatment process. The enzymatic digestibility of the biomass [Water Hyacinth: Eichhornia crassipes] after pretreatment was determined by measuring the hydrolysis yield of the pretreated material obtained from twenty four different pretreatment conditions. These included different concentrations of sulphuric acid (0.0, 1.0, 2.0 and 3.0%, at two different temperatures (108 and 121 ºC for different residence times (1.0, 2.0 and 3.0h.The highest reducing sugar yield (36.65 g/L from enzymatic hydrolysis was obtained when plant material was pretreated at 121 ºC for 1.0 h residence time using 3.0% (v/v sulphuric acid and at 1:10 (w/v solid to liquid ratio. The total reducing sugars obtained from the two-stage process (pretreatment + enzymatic hydrolysis was 69.6g/L. The resulting sugars were fermented into ethanol by using Saccharomyces cerevisiae. The ethanol yield from the enzymatic hydrolyzate was 95.2% of the theoretical yield (0.51g/g glucose, as determined by GS-MS, and nearly 100% since no reducing sugars were detected in the fermenting media by TLC and DNS analysis.

  14. Optimization of enzymatic hydrolysis of guar gum using response surface methodology.

    Science.gov (United States)

    Mudgil, Deepak; Barak, Sheweta; Khatkar, B S

    2014-08-01

    Guar gum is a polysaccharide obtained from guar seed endosperm portion. Enzymatically hydrolyzed guar gum is low in viscosity and has several health benefits as dietary fiber. In this study, response surface methodology was used to determine the optimum conditions for hydrolysis that give minimum viscosity of guar gum. Central composite was employed to investigate the effects of pH (3-7), temperature (20-60 °C), reaction time (1-5 h) and cellulase concentration (0.25-1.25 mg/g) on viscosity during enzymatic hydrolysis of guar (Cyamopsis tetragonolobus) gum. A second order polynomial model was developed for viscosity using regression analysis. Results revealed statistical significance of model as evidenced from high value of coefficient of determination (R(2) = 0.9472) and P < 0.05. Viscosity was primarily affected by cellulase concentration, pH and hydrolysis time. Maximum viscosity reduction was obtained when pH, temperature, hydrolysis time and cellulase concentration were 6, 50 °C, 4 h and 1.00 mg/g, respectively. The study is important in optimizing the enzymatic process for hydrolysis of guar gum as potential source of soluble dietary fiber for human health benefits.

  15. High-solids loading enzymatic hydrolysis of waste papers for biofuel production

    International Nuclear Information System (INIS)

    Wang, Lei; Templer, Richard; Murphy, Richard J.

    2012-01-01

    Highlights: ► Waste papers have great potential as a feedstock for bioethanol production. ► A wet blending step would significantly enhance enzymatic hydrolysis efficiency. ► High-solids loading saccharification was performed successfully on waste papers. ► Saccharification data were from four types of paper and two enzyme alternatives. ► Enzymatic hydrolysis kinetic models were validated by experimental data. -- Abstract: Waste papers (newspaper, office paper, magazines and cardboard in this study) with 50–73% (w/w oven dry weight) carbohydrate contents have considerable potential as raw materials for bioethanol production. A particle size reduction step of wet blending prior to enzymatic hydrolysis of newspaper was found to increase the glucan conversion efficiency by up to 10%. High-solids loading hydrolysis at 15% (w/w) of four types of paper using two enzyme alternatives, Celluclast 1.5L supplemented with Novozyme 188 and Cellic Ctec 1 (Novozymes A/S, Demark), at various enzyme concentrations were successfully performed in a lab-scale overhead-stirred reactor. This work has identified the relative saccharification performance for the four types of paper and shows office paper and cardboard to be more suitable for producing bioethanol than newspaper or magazine paper. The experimental data were also very well described by a modified, simple three parameter glucan and xylan hydrolysis model. These findings provide the possibility for incorporating this validated kinetic model into process designs required for commercial scale bioethanol production from waste paper resources.

  16. Enzymatic hydrolysis of Grass Carp fish skin hydrolysates able to promote the proliferation of Streptococcus thermophilus.

    Science.gov (United States)

    Wang, Xiao-Nan; Qin, Mei; Feng, Yu-Ying; Chen, Jian-Kang; Song, Yi-Shan

    2017-09-01

    The promotion effect on proliferation of Streptococcus thermophilus by enzymatic hydrolysates of aquatic products was firstly studied. The effect of influencing factors of the hydrolysis on the growth of S. thermophilus was investigated. Grass Carp fish skin was hydrolysed to peptides by enzymatic hydrolysis using protease ProteAX, and for the S. thermophilus growth, the optimal enzymatic hydrolysis conditions were temperature of 60 °C, initial pH of 9.0, enzyme concentration of 10 g kg -1 , hydrolysis time of 80 min, and ratio of material to liquid of 1:2. The Grass Carp fish skin hydrolysate (GCFSH) prepared under the optimum conditions was fractionated to five fragments (GCFSH 1, GCFSH 2, GCFSH 3, GCFSH 4, GCFSH 5) according to molecular weight sizes, in which the fragments GCFSH 4 and GCFSH 5, with molecular weights of less than 1000 Da, significantly promoted the growth of S. thermophilus. The hydrolysis process of Grass Carp fish skin can be simplified, and the peptides with molecular weights below 1000 Da in the hydrolysates are the best nitrogen source for proliferation of S. thermophilus. This work can provide a fundamental theoretical basis for the production of multi-component functional foods, especially in milk drinks or yogurt. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  17. Modeling enzymatic hydrolysis of lignocellulosic substrates using confocal fluorescence microscopy I: filter paper cellulose.

    Science.gov (United States)

    Luterbacher, Jeremy S; Moran-Mirabal, Jose M; Burkholder, Eric W; Walker, Larry P

    2015-01-01

    Enzymatic hydrolysis is one of the critical steps in depolymerizing lignocellulosic biomass into fermentable sugars for further upgrading into fuels and/or chemicals. However, many studies still rely on empirical trends to optimize enzymatic reactions. An improved understanding of enzymatic hydrolysis could allow research efforts to follow a rational design guided by an appropriate theoretical framework. In this study, we present a method to image cellulosic substrates with complex three-dimensional structure, such as filter paper, undergoing hydrolysis under conditions relevant to industrial saccharification processes (i.e., temperature of 50°C, using commercial cellulolytic cocktails). Fluorescence intensities resulting from confocal images were used to estimate parameters for a diffusion and reaction model. Furthermore, the observation of a relatively constant bound enzyme fluorescence signal throughout hydrolysis supported our modeling assumption regarding the structure of biomass during hydrolysis. The observed behavior suggests that pore evolution can be modeled as widening of infinitely long slits. The resulting model accurately predicts the concentrations of soluble carbohydrates obtained from independent saccharification experiments conducted in bulk, demonstrating its relevance to biomass conversion work. © 2014 Wiley Periodicals, Inc.

  18. Combined enzymatic hydrolysis and fermentation of hemicellulose to 2,3-butanediol

    Energy Technology Data Exchange (ETDEWEB)

    Yu, E.K.C.; Deschatelets, L.; Saddler, J.N.

    1984-06-01

    Hemicellulose-rich fractions from several agricultural residues were converted to 2,3-butanediol by a combined enzymatic hydrolysis and fermentation process. Culture filtrates from Trichoderma harzianum E58 were used to hydrolyze the substrates while Klebsiella pneumoniae fermented the liberated sugars to 2,3-butanediol. Approximately 50-60% of a 5% (w/v) xylan preparation could be hydrolyzed and quantitatively converted to 2,3-butanediol using this procedure. Although enzymatic hydrolysis was optimal at pH 5.0 and 50/sup 0/C, the combined hydrolysis and fermentation was most efficient at pH 6.5 and 30/sup 0/C. Combined hydrolysis and fermentation resulted in butanediol levels that were 20-40% higher than could be obtained with a separate hydrolysis and fermentation process. The hemicellulose-rich water-soluble fractions obtained from a variety of steam-exploded agricultural residues could be readily used by the combined hydrolysis and fermentation approach resulting in butanediol yields of 0.4-0.5 g/g of reducing sugar utilized.

  19. Scale-up and integration of alkaline hydrogen peroxide pretreatment, enzymatic hydrolysis, and ethanolic fermentation.

    Science.gov (United States)

    Banerjee, Goutami; Car, Suzana; Liu, Tongjun; Williams, Daniel L; Meza, Sarynna López; Walton, Jonathan D; Hodge, David B

    2012-04-01

    Alkaline hydrogen peroxide (AHP) has several attractive features as a pretreatment in the lignocellulosic biomass-to-ethanol pipeline. Here, the feasibility of scaling-up the AHP process and integrating it with enzymatic hydrolysis and fermentation was studied. Corn stover (1 kg) was subjected to AHP pretreatment, hydrolyzed enzymatically, and the resulting sugars fermented to ethanol. The AHP pretreatment was performed at 0.125 g H(2) O(2) /g biomass, 22°C, and atmospheric pressure for 48 h with periodic pH readjustment. The enzymatic hydrolysis was performed in the same reactor following pH neutralization of the biomass slurry and without washing. After 48 h, glucose and xylose yields were 75% and 71% of the theoretical maximum. Sterility was maintained during pretreatment and enzymatic hydrolysis without the use of antibiotics. During fermentation using a glucose- and xylose-utilizing strain of Saccharomyces cerevisiae, all of the Glc and 67% of the Xyl were consumed in 120 h. The final ethanol titer was 13.7 g/L. Treatment of the enzymatic hydrolysate with activated carbon prior to fermentation had little effect on Glc fermentation but markedly improved utilization of Xyl, presumably due to the removal of soluble aromatic inhibitors. The results indicate that AHP is readily scalable and can be integrated with enzyme hydrolysis and fermentation. Compared to other leading pretreatments for lignocellulosic biomass, AHP has potential advantages with regard to capital costs, process simplicity, feedstock handling, and compatibility with enzymatic deconstruction and fermentation. Biotechnol. Bioeng. 2012; 109:922-931. © 2011 Wiley Periodicals, Inc. Copyright © 2011 Wiley Periodicals, Inc.

  20. Enzymatic Hydrolysis of Oleuropein from Olea europea (Olive Leaf Extract and Antioxidant Activities

    Directory of Open Access Journals (Sweden)

    Jiao-Jiao Yuan

    2015-02-01

    Full Text Available Oleuropein (OE, the main polyphenol in olive leaf extract, is likely to decompose into hydroxytyrosol (HT and elenolic acid under the action of light, acid, base, high temperature. In the enzymatic process, the content of OE in olive leaf extract and enzyme are key factors that affect the yield of HT. A selective enzyme was screened from among 10 enzymes with a high OE degradation rate. A single factor (pH, temperature, time, enzyme quantity optimization process and a Box-Behnken design were studied for the enzymatic hydrolysis of 81.04% OE olive leaf extract. Additionally, enzymatic hydrolysis results with different substrates (38.6% and 81.04% OE were compared and the DPPH antioxidant properties were also evaluated. The result showed that the performance of hydrolysis treatments was best using hemicellulase as a bio-catalyst, and the high purity of OE in olive extract was beneficial to biotransform OE into HT. The optimal enzymatic conditions for achieving a maximal yield of HT content obtained by the regression were as follows: pH 5, temperature 55 °C and enzyme quantity 55 mg. The experimental result was 11.31% ± 0.15%, and the degradation rate of OE was 98.54%. From the present investigation of the antioxidant activity determined by the DPPH method, the phenol content and radical scavenging effect were both decreased after enzymatic hydrolysis by hemicellulase. However, a high antioxidant activity of the ethyl acetate extract enzymatic hydrolysate (IC50 = 41.82 μg/mL was demonstated. The results presented in this work suggested that hemicellulase has promising and attractive properties for industrial production of HT, and indicated that HT might be a valuable biological component for use in pharmaceutical products and functional foods.

  1. Investigation of an "alternate water supply system" in enzymatic hydrolysis in the processive endocellulase Cel7A from Rasamsonia emersonii by molecular dynamics simulation.

    Science.gov (United States)

    Sun, Xun; Qian, Meng-Dan; Guan, Shan-Shan; Shan, Ya-Ming; Dong, Ying; Zhang, Hao; Wang, Song; Han, Wei-Wei

    2017-02-01

    Cel7A from Rasamsonia emersonii is one of the processive endocellulases classified under family 7 glycoside hydrolase. Molecular dynamics simulations were carried out to obtain the optimized sliding and hydrolyzing conformations, in which the reducing ends of sugar chains are located on different sites. Hydrogen bonds are investigated to clarify the interactions between protein and substrate in either conformation. Nine hydrogen bonding interactions are identified in the sliding conformation, and six similar interactions are also found correspondingly in the hydrolyzing conformation. In addition, four strong hydrophobic interactions are also determined. The domain cross-correlation map analysis shows movement correlation of protein including autocorrelation between residues. The root mean square fluctuations analysis represents the various flexibilities of different fragment in the two conformations. Comparing the two conformations reveals the water-supply mechanism of selective hydrolysis of cellulose in Cel7A. The mechanism can be described as follow. When the reducing end of substrate slides from the unhydrolyzing site (sliding conformation) to the hydrolyzing site (hydrolyzing conformation), His225 is pushed down and rotated, the rotation leads to the movement of Glu209 with the interstrand hydrogen bonding in β-sheet. It further makes Asp211 close to the hydrolysis center and provides a water molecule bounding on its carboxyl in the previous unhydrolyzing site. After the hydrolysis takes place and the product is excluded from the enzyme, the Asp211 comes back to its initial position. In summary, Asp211 acts as an elevator to transport outer water molecules into the hydrolysis site for every other glycosidic bond. © 2016 Wiley Periodicals, Inc.

  2. Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation

    OpenAIRE

    Hudečková, Helena; Šupinová, Petra; Ing. Mgr. Libor Babák, Ph.D., MBA

    2017-01-01

    Finding of optimal hydrolysis conditions is important for increasing the yield of saccharides. 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...

  3. Influence of homogenization treatment on physicochemical properties and enzymatic hydrolysis rate of pure cellulose fibers.

    Science.gov (United States)

    Jacquet, N; Vanderghem, C; Danthine, S; Blecker, C; Paquot, M

    2013-02-01

    The aim of this study is to compare the effect of different homogenization treatments on the physicochemical properties and the hydrolysis rate of a pure bleached cellulose. Results obtained show that homogenization treatments improve the enzymatic hydrolysis rate of the cellulose fibers by 25 to 100 %, depending of the homogenization treatment applied. Characterization of the samples showed also that homogenization had an impact on some physicochemical properties of the cellulose. For moderate treatment intensities (pressure below 500 b and degree of homogenization below 25), an increase of water retention values (WRV) that correlated to the increase of the hydrolysis rate was highlighted. Result also showed that the overall crystallinity of the cellulose properties appeared not to be impacted by the homogenization treatment. For higher treatment intensities, homogenized cellulose samples developed a stable tridimentional network that contributes to decrease cellulase mobility and slowdown the hydrolysis process.

  4. Combined enzymatic hydrolysis and fermentation of aspenwood using enzymes derived from Trichoderma harzianum E58

    Energy Technology Data Exchange (ETDEWEB)

    1990-05-01

    Energy, Mines and Resources Canada supported a project with Forintek Canada Corp. directed toward the conversion of aspenwood to ethanol. This conversion is carried out through three sequential steps, steam explosion/extraction, hydrolysis and fermentation. This investigation involved study of the factors which governed the rate and extent of cellulose hydrolysis. The physical and chemical state of the material to be hydrolysed, enzyme concentation and adsorption onto residue, end-product characterization and inhibition, recycling of enzymes and cellulose, and growth media for the fungus were among the variables examined. The research demonstrated the interdependency between pretreatment, cellulose hydrolysis, hemicellulose fermentation and enzyme production. It was also determined that because of the amount of cellulose required for enzyme production and the difficulties encountered in recovering/recycling the celluloses, further work is required in order to commercialize an enzymatic hydrolysis process based on Trichoderma harzianum E58.

  5. Response surface optimization of enzymatic hydrolysis of narrow-leaf cattail for bioethanol production

    International Nuclear Information System (INIS)

    Ruangmee, Arrisa; Sangwichien, Chayanoot

    2013-01-01

    Highlights: • The cellulose of pretreated sample was higher than untreated sample. • Lower hemicellulose and lignin were enhanced of hydrolyzed cellulose to sugar. • The predicted result of enzymatic hydrolysis process was fitted by quadratic model. • Predicted data was good agreement with the experimental data; with 95% confidence. - Abstract: Narrow-leaf cattail was employed as lignocellulosic biomass substrate for the investigation of the hydrolysis process of lignocellulosic ethanol. Cellulose saccharification into a high yield of fermentable sugar is an important step in ethanol production. Response surface methodology was utilized in the study of variables affecting enzymatic hydrolysis on the released glucose and xylose. Five levels (−2, −1, 0, +1, +2) of independent variable factors; cellulase (5–25 FPU/g substrate), β-glucosidase (0–20 U/g substrate), hydrolysis temperature (30–50 °C), and hydrolysis time (24–96 h), were randomly setup by using the Design of Experiment program. The significance of the regression model was high; with 95% confidence interval (less than 5% error). The predicted result after optimization was also in good agreement with the experimental data. An optimal condition; 13.50 FPU/g substrate, 16.50 U/g substrate, 50 °C and 24 h, was obtained, yielding a released glucose of 552.9 mg/g substrate (75.6% saccharification) and a released xylose of 74.0 mg/g substrate (45.6% saccharification)

  6. Nutritional composition of different grades of edible bird's nest and its enzymatic hydrolysis

    Science.gov (United States)

    Noor, Hidayati Syamimi Mohd; Babji, Abdul Salam; Lim, Seng Joe

    2018-04-01

    Edible bird nest (EBN) is a powerful and nutritious food usually consumed by the Chinese Community and it is considered among the most expensive animal products which are made up by salivation of swiftlets (Aerodramus fuciphagus). The other 5% to 10% are made up of foreign matters such as feathers, faecal matter and dirt. The EBN is graded based on its aesthetics as well as its cleaning processes. The aim of this study were to determine and compare EBN of different grades (A, B, C, D) in terms of proximate composition and amino acid profile, and next to enzymatically hydrolyse and determine the degree of hydrolysis (DH) and the recovery percentage of EBN hydrolysates. The enzymatic hydrolysis were performed as an alternative cleaning process of the various grades of EBN, where the glycoproteins were hydrolysed to glycopeptides, making them soluble and leaving behind other insoluble impurities. The results in this study showed that EBN contained high crude protein content: 60.59% (EBNA), 59.50% (EBNB), 54.29% (EBNC) and 56.57% (EBND). Lower grade EBNs (EBNC and EBND) has much higher ash content, i.e. impurities, compared to higher grade EBNs (EBNA and EBNB). In terms of amino acid profile, EBND showed the highest total amino acids compared to EBNA, EBNB and EBNC, with serine and aspartic acid being the main amino acids. Treating the EBN with alcalase for 1.0 - 4.0 hours produced hydrolysates with different degree of hydrolysis (DH), ranging from 10.83 %DH (EBNA) to 13.79 %DH (EBNC). The recovery of EBN after enzymatic hydrolysis range from 89 % (EBNB) to 99% (EBNA). Overall, results showed nutritional composition and amino acid profile of EBN of various grades were significantly different in its nutritional quality, while the enzymatic hydrolysis has successfully separated the impurities from the lower grades EBN.

  7. Aqueous two-phase systems for extractive enzymatic hydrolysis of biomass

    DEFF Research Database (Denmark)

    Bussamra, Bianca Consorti; Azzoni, Sindelia Freitas; Mussatto, Solange I.

    and enzymes, phase diagrams and volumetric ratios. The results of this project will make possible to design a process that enables high sugar concentration during the hydrolysis reaction, overcoming one of the biggest drawbacks regarding the production of second-generation ethanol: the enzymatic inhibition...... optimal aqueous two-phase systems for the separation of sugars and enzymes, which allow the development of an improved second-generation ethanol process.......Sugars derived from lignocellulosic materials are the main carbon sources in bio-based processes aiming to produce renewable fuels and chemicals. One of the major drawbacks during enzymatic hydrolysis of lignocellulosic materials to obtainsugars is the inhibition of enzymes by reaction products...

  8. Rapid near infrared spectroscopy for prediction of enzymatic hydrolysis of corn bran after various pretreatments

    DEFF Research Database (Denmark)

    Baum, Andreas; Wittrup Agger, Jane; Meyer, Anne S.

    2012-01-01

    Efficient generation of a fermentable hydrolysate is a primary requirement in the utilization of fibrous plant biomass as feedstocks in bioethanol processes. The first biomass conversion step usually involves a hydrothermal pretreatment before enzymatic hydrolysis. The purpose of the pretreatment...... step is to increase the responsivity of the substrate to enzymatic attack and the type of pretreatment affects the enzymatic conversion efficiency. Destarched corn bran is a fibrous, heteroxylan-rich side-stream from the starch industry which may be used as a feedstock for bioethanol production...... release of different levels of arabinose, xylose and glucose from all the differently pretreated destarched corn bran samples. The present study also demonstrates a generic, non-destructive solution to determine the enzymatic monosaccharide release from polymers in biomass side-streams, thereby...

  9. Comparison of the role that entropy has played in processes of non-enzymatic and enzymatic catalysis

    International Nuclear Information System (INIS)

    Dixon Pineda, Manuel Tomas

    2012-01-01

    The function that entropy has played is compared in processes of non-enzymatic and enzymatic catalysis. The processes followed are showed: the kinetics of the acid hydrolysis of 3-pentyl acetate and cyclopentyl acetate catalyzed by hydrochloric acid and enzymatic hydrolysis of ethyl acetate and γ-butyrolactone catalyzed by pig liver esterase. The activation parameters of Eyring were determined for each process and interpreted the contribution of the entropy of activation for catalysis in this type of model reactions. (author) [es

  10. Preparation of immobilized growing cells and enzymatic hydrolysis of sawdust

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1984-01-01

    Trichoderma reesei cells were immobilized by radiation polymerization using porous materials such as non-woven material and sawdust, and the enzymatic hydrolysis of sawdust with the enzyme solution from the immobilized growing cells was studied. The filter paper activity, which shows the magnitude of cellulase production in the immobilized cells, was comparable with that in the intact cells. The filter paper activity was affected by addition concentration of monomer and porous materials. The cells in the immobilized cells grew to be adhered on the surface of the fibrous polymers. Sawdust, which was pretreated by irradiation technique, was effectively hydrolyzed with the enzyme solution resulting from the culture of the immobilized cells, in which the glucose yield increased increasing the culture time of the immobilized cells. (author)

  11. Role of supramolecular cellulose structures in enzymatic hydrolysis of plant cell walls

    DEFF Research Database (Denmark)

    Thygesen, Lisbeth Garbrecht; Hidayat, Budi Juliman; Johansen, Katja Salomon

    2011-01-01

    The study of biomass deconstruction by enzymatic hydrolysis has hitherto not focussed on the importance of supramolecular structures of cellulose. In lignocellulose fibres, regions with a different organisation of the microfibrils are present. These regions are called dislocations or slip planes ...... the initial part of enzymatic hydrolysis of cellulose. The implications of this phenomenon have not yet been recognized or explored within cellulosic biofuels....

  12. The effect of high intensity mixing on the enzymatic hydrolysis of concentrated cellulose fiber suspensions

    Science.gov (United States)

    Joseph R. Samaniuk; C. Tim Scott; Thatcher W. Root; Daniel J. Klingenberg

    2011-01-01

    Enzymatic hydrolysis of lignocellulosic biomass in a high shear environment was examined. The conversion of cellulose to glucose in samples mixed in a torque rheometer producing shear flows similar to those found in twin screw extruders was greater than that of unmixed samples. In addition, there is a synergistic effect of mixing and enzymatic hydrolysis; mixing...

  13. Structural Changes of Lignin after Liquid Hot Water Pretreatment and Its Effect on the Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Wen Wang

    2016-01-01

    Full Text Available During liquid hot water (LHW pretreatment, lignin is mostly retained in the pretreated biomass, and the changes in the chemical and structural characteristics of lignin should probably refer to re-/depolymerization, solubilization, or glass transition. The residual lignin could influence the effective enzymatic hydrolysis of cellulose. The pure lignin was used to evaluate the effect of LHW process on its structural and chemical features. The surface morphology of LHW-treated lignin observed with the scanning electron microscopy (SEM was more porous and irregular than that of untreated lignin. Compared to the untreated lignin, the surface area, total pore volume, and average pore size of LHW-treated lignin tested with the Brunner-Emmet-Teller (BET measurement were increased. FTIR analysis showed that the chemical structure of lignin was broken down in the LHW process. Additionally, the impact of untreated and treated lignin on the enzymatic hydrolysis of cellulose was also explored. The LHW-treated lignin had little impact on the cellulase adsorption and enzyme activities and somehow could improve the enzymatic hydrolysis of cellulose.

  14. Enzymatic hydrolysis of organic phosphorus in swine manure and soil.

    Science.gov (United States)

    He, Zhongqi; Griffin, Timothy S; Honeycutt, C Wayne

    2004-01-01

    Organic phosphorus (Po) exists in many chemical forms that differ in their susceptibility to hydrolysis and, therefore, bioavailability to plants and microorganisms. Identification and quantification of these forms may significantly contribute to effective agricultural P management. Phosphatases catalyze reactions that release orthophosphate (Pi) from Po compounds. Alkaline phosphatase in tris-HCl buffer (pH 9.0), wheat (Triticum aestivum L.) phytase in potassium acetate buffer (pH 5.0), and nuclease P1 in potassium acetate buffer (pH 5.0) can be used to classify and quantify Po in animal manure. Background error associated with different pH and buffer systems is observed. In this study, we improved the enzymatic hydrolysis approach and tested its applicability for investigating Po in soils, recognizing that soil and manure differ in numerous physicochemical properties. We applied (i) acid phosphatase from potato (Solanum tuberosum L.), (ii) acid phosphatases from both potato and wheat germ, and (iii) both enzymes plus nuclease P1 to identify and quantify simple labile monoester P, phytate (myo-inositol hexakis phosphate)-like P, and DNA-like P, respectively, in a single pH/buffer system (100 mM sodium acetate, pH 5.0). This hydrolysis procedure released Po in sequentially extracted H2O, NaHCO3, and NaOH fractions of swine (Sus scrofa) manure, and of three sandy loam soils. Further refinement of the approach may provide a universal tool for evaluating hydrolyzable Po from a wide range of sources.

  15. Use of a two-chamber reactor to improve enzymatic hydrolysis and fermentation of lignocellulosic materials

    International Nuclear Information System (INIS)

    Viola, E.; Zimbardi, F.; Valerio, V.; Nanna, F.; Battafarano, A.

    2013-01-01

    Highlights: ► A two-chamber reactor is proposed to improve bioethanol production. ► Hydrolysis and fermentation can be made simultaneous at different temperatures. ► The residue of lignin can be easily separated at the end of the process. -- Abstract: A special type of bioreactor was designed and tested in order to improve the bioethanol production from lignocellulosic materials via enzymatic hydrolysis and fermentation. The reactor consists of two chambers kept at different temperatures and separated by a porous medium, through which the solutes can diffuse. The reactor was tested using as substrate wheat straw previously steam exploded and detoxified. The yields of cellulose hydrolysis and glucose fermentation obtained using this reactor were compared to those obtained by simultaneous enzymatic hydrolysis and fermentation (SSF) carried out in only one vessel. The results showed that a significant increase in the ethanol yield (20%) can be achieved by using this bioreactor. An additional advantage of the reactor is the confinement of the solid lignin in one chamber, allowing a simplified separation process between broth and unreacted residue.

  16. Chemical and Enzymatic Hydrolysis of Polyurethane/Polylactide Blends

    Directory of Open Access Journals (Sweden)

    Joanna Brzeska

    2015-01-01

    Full Text Available Polyether-esterurethanes containing synthetic poly[(R,S-3-hydroxybutyrate] (R,S-PHB and polyoxytetramethylenediol in soft segments and polyesterurethanes with poly(ε-caprolactone and poly[(R,S-3-hydroxybutyrate] were blended with poly([D,L]-lactide (PLA. The products were tested in terms of their oil and water absorption. Oil sorption tests of polyether-esterurethane revealed their higher response in comparison to polyesterurethanes. Blending of polyether-esterurethanes with PLA caused the increase of oil sorption. The highest water sorption was observed for blends of polyether-esterurethane, obtained with 10% of R,S-PHB in soft segments. The samples mass of polyurethanes and their blends were almost not changed after incubation in phosphate buffer and trypsin and lipase solutions. Nevertheless the molecular weight of polymers was significantly reduced after degradation. It was especially visible in case of incubation of samples in phosphate buffer what suggested the chemical hydrolysis of polymer chains. The changes of surface of polyurethanes and their blends, after incubation in both enzymatic solutions, indicated on enzymatic degradation, which had been started despite the lack of mass lost. Polyurethanes and their blends, contained more R,S-PHB in soft segments, were degraded faster.

  17. Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Wooley, R.; Ruth, M.; Sheehan, J.; Ibsen, K.; Majdeski, H.; Galvez, A.

    1999-07-20

    The National Renewable Energy Laboratory (NREL) has undertaken a complete review and update of the process design and economic model for the biomass-to-ethanol enzymatic based process. The process design includes the core technologies being researched by the U.S. Department of Energy (DOE): prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production. In addition, all ancillary areas--feed handling, product recovery and purification, wastewater treatment lignin burner and boiler--turbogenerator, and utilities--are included. NREL engaged Delta-T Corporation to assist in the process design evaluation, equipment costing, and overall plant integration. The process design and costing for the lignin burner and boiler turbogenerator has been reviewed by Reaction Engineering Inc. and the wastewater treatment by Merrick and Company. An overview of both reviews is included here. The purpose of this update was to ensure that the process design and equipment costs were reasonable and consistent with good engineering practice for plants of this type using available technical data. This work has resulted in an economic model that can be used to predict the cost of producing ethanol from cellulosic biomass using this technology if a plant were to be built in the next few years. The model was also extended using technology improvements that are expected to be developed based on the current DOE research plan. Future process designs and cost estimates are given for the years 2005, 2010, and 2015.

  18. Process Design and Economics for Biochemical Conversion of Lignocellulosic Biomass to Ethanol: Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Humbird, D.; Davis, R.; Tao, L.; Kinchin, C.; Hsu, D.; Aden, A.; Schoen, P.; Lukas, J.; Olthof, B.; Worley, M.; Sexton, D.; Dudgeon, D.

    2011-03-01

    This report describes one potential biochemical ethanol conversion process, conceptually based upon core conversion and process integration research at NREL. The overarching process design converts corn stover to ethanol by dilute-acid pretreatment, enzymatic saccharification, and co-fermentation. Building on design reports published in 2002 and 1999, NREL, together with the subcontractor Harris Group Inc., performed a complete review of the process design and economic model for the biomass-to-ethanol process. This update reflects NREL's current vision of the biochemical ethanol process and includes the latest research in the conversion areas (pretreatment, conditioning, saccharification, and fermentation), optimizations in product recovery, and our latest understanding of the ethanol plant's back end (wastewater and utilities). The conceptual design presented here reports ethanol production economics as determined by 2012 conversion targets and 'nth-plant' project costs and financing. For the biorefinery described here, processing 2,205 dry ton/day at 76% theoretical ethanol yield (79 gal/dry ton), the ethanol selling price is $2.15/gal in 2007$.

  19. Onopordum nervosum as biomass source: some aspects of its production and transformation by enzymatic hydrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Manzanares, P; Negro, M J; Saez, R; Martin, C [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain). Inst. de Energias Renovables; Fernandez, J [ETSIA, Madrid (Spain). Dept. de Produccion Vegetal, Botanica y Proteccion Vegetal

    1993-01-01

    Onopordum nervosum, a lignocellulosic herbaceous species of the Iberian Peninsula, has been selected as a suitable biomass source to be used in transformation processes to obtain energy or industrial products. In this work, the effectiveness of different chemical pretreatments as a preliminary step to the enzymatic hydrolysis of this lignocellulosic biomass was evaluated. In order to determine biomass productivity, field assays were carried out in 1988 and 1989 using different planting densities and evaluating the effect to top fertilization. Biomass yields between 12 and 20 t ha[sup -1] were obtained, depending on the year and the planting density assayed. No significant differences were found in production rates when top fertilization was applied. Enzymatic hydrolysis of O.nervosum using a cellulolytic complex from Trichoderma longibrachiatum QM9414, gave low yields when untreated lignocellulosic biomass was used as substrate. Among different chemical pretreatments tested, ethanol and butanol solubilizations in the presence of a basic catalyst gave the best results. For the most effective pretreatment conditions, a delignification of about 30% and a complete recovery of glucose in the treated substrate were obtained both for butanol and ethanol. The highest enzymatic hydrolysis yields were found when ethanol was used as solvent, giving a saccharification efficiency of about 66% which, compared to the 23% for the native substrate, indicates the remarkable increment in the susceptibility of the cellulose to enzyme attack effected by this pretreatment. (author)

  20. Enzymatic Hydrolysis Does Not Reduce the Biological Reactivity of Soybean Proteins for All Allergic Subjects.

    Science.gov (United States)

    Panda, Rakhi; Tetteh, Afua O; Pramod, Siddanakoppalu N; Goodman, Richard E

    2015-11-04

    Many soybean protein products are processed by enzymatic hydrolysis to attain desirable functional food properties or in some cases to reduce allergenicity. However, few studies have investigated the effects of enzymatic hydrolysis on the allergenicity of soybean products. In this study the allergenicity of soybean protein isolates (SPI) hydrolyzed by Alcalase, trypsin, chymotrypsin, bromelain, or papain was evaluated by IgE immunoblots using eight soybean-allergic patient sera. The biological relevance of IgE binding was evaluated by a functional assay using a humanized rat basophilic leukemia (hRBL) cell line and serum from one subject. Results indicated that hydrolysis of SPI by the enzymes did not reduce the allergenicity, and hydrolysis by chymotrypsin or bromelain has the potential to increase the allergenicity of SPI. Two-dimensional (2D) immunoblot and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of the chymotrypsin-hydrolyzed samples indicated fragments of β-conglycinin protein are responsible for the apparent higher allergenic potential of digested SPI.

  1. Process Design Report for Stover Feedstock: Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis for Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Aden, A. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ruth, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibsen, K. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Jechura, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Neeves, K. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sheehan, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wallace, B. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Montague, L. [Harris Group, Seattle, WA (United States); Slayton, A. [Harris Group, Seattle, WA (United States); Lukas, J. [Harris Group, Seattle, WA (United States)

    2002-06-01

    The U.S. Department of Energy (DOE) is promoting the development of ethanol from lignocellulosic feedstocks as an alternative to conventional petroleum-based transportation fuels. DOE funds both fundamental and applied research in this area and needs a method for predicting cost benefits of many research proposals. To that end, the National Renewable Energy Laboratory (NREL) has modeled many potential process designs and estimated the economics of each process during the last 20 years. This report is an update of the ongoing process design and economic analyses at NREL.

  2. A Factorial Analysis Study on Enzymatic Hydrolysis of Fiber Pressed Oil Palm Frond for Bioethanol Production

    Science.gov (United States)

    Hashim, F. S.; Yussof, H. W.; Zahari, M. A. K. M.; Illias, R. M.; Rahman, R. A.

    2016-03-01

    Different technologies have been developed to for the conversion of lignocellulosic biomass to suitable fermentation substrates for bioethanol production. The enzymatic conversion of cellulose seems to be the most promising technology as it is highly specific and does not produce substantial amounts of unwanted byproducts. The effects of agitation speed, enzyme loading, temperature, pH and reaction time on the conversion of glucose from fiber pressed oil palm frond (FPOPF) for bioethanol production were screened by statistical analysis using response surface methodology (RSM). A half fraction two-level factorial analysis with five factors was selected for the experimental design to determine the best enzymatic conditions that produce maximum amount of glucose. FPOPF was pre-treated with alkaline prior to enzymatic hydrolysis. The enzymatic hydrolysis was performed using a commercial enzyme Cellic CTec2. From this study, the highest yield of glucose concentration was 9.736 g/L at 72 hours reaction time at 35 °C, pH 5.6, and 1.5% (w/v) of enzyme loading. The model obtained was significant with p-value model had a maximum point which is likely to be the optimum point and possible for the optimization process.

  3. Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis for Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Aden, A.; Ruth, M.; Ibsen, K.; Jechura, J.; Neeves, K.; Sheehan, J.; Wallace, B.; Montague, L.; Slayton, A.; Lukas, J.

    2002-06-01

    This report is an update of NREL's ongoing process design and economic analyses of processes related to developing ethanol from lignocellulosic feedstocks. The U.S. Department of Energy (DOE) is promoting the development of ethanol from lignocellulosic feedstocks as an alternative to conventional petroleum-based transportation fuels. DOE funds both fundamental and applied research in this area and needs a method for predicting cost benefits of many research proposals. To that end, the National Renewable Energy Laboratory (NREL) has modeled many potential process designs and estimated the economics of each process during the last 20 years. This report is an update of the ongoing process design and economic analyses at NREL. We envision updating this process design report at regular intervals; the purpose being to ensure that the process design incorporates all new data from NREL research, DOE funded research and other sources, and that the equipment costs are reasonable and consistent with good engineering practice for plants of this type. For the non-research areas this means using equipment and process approaches as they are currently used in industrial applications. For the last report, published in 1999, NREL performed a complete review and update of the process design and economic model for the biomass-to-ethanol process utilizing co-current dilute acid prehydrolysis with simultaneous saccharification (enzymatic) and co-fermentation. The process design included the core technologies being researched by the DOE: prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production. In addition, all ancillary areas--feed handling, product recovery and purification, wastewater treatment (WWT), lignin combustor and boiler-turbogenerator, and utilities--were included. NREL engaged Delta-T Corporation (Delta-T) to assist in the process design evaluation, the process equipment costing, and overall plant integration. The process design

  4. Pretreatment by radiation and acids of chaff and its effect on enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Kumakura, M.; Kaetsu, I.

    1984-01-01

    The effect of pretreatment by radiation and acids—sulfuric, hydrochloric and acetic—on the enzymatic hydrolysis of chaff was studied. The combination of radiation and acids accelerates subsequent crushing and enzymatic hydrolysis. The percentage of fine powder below 115 mesh, after the crushing and the glucose yield on subsequent enzymatic hydrolysis, increased with increasing acid concentration, treatment time and irradiation dose. Radiation and hydrochloric acid pretreatment was the most effective in giving a high glucose conversion yield (about 90%). Irradiation dose, acid concentration, treatment temperature and treatment time were 20 Mrad, 0·5%, 70°C, and 5 h, respectively

  5. Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation

    Directory of Open Access Journals (Sweden)

    Helena Hudečková

    2017-01-01

    Full Text Available Finding of optimal hydrolysis conditions is important for increasing the yield of saccharides. 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. As raw material was used waste bread from local cafe. Waste bread was pretreated by grinding into small particles. Hydrolysis was performed in 100 mL of 15 % (w/v waste bread particles in the form of water suspension. Waste bread was hydrolysed by two commercial enzymes. For the liquefaction was used α‑amylase (BAN 240 L. The saccharification was performed by glucoamylase (AMG 300 L. Optimal conditions for α‑amylase (pH 6; 80 °C were found. The yield of total sugars was 67.08 g∙L-1 (calculated to maltose. As optimal conditions for glucoamylase (pH 4.2; 60 °C were found. Amount of glucose was 70.28 g∙L1. The time of waste bread liquefaction was 180 minutes. The time of saccharification was 90 minutes. The results were presented at the conference CECE Junior 2014.

  6. [Response surface method optimize of nano-silica solid dispersion technology assistant enzymatic hydrolysis preparation genistein].

    Science.gov (United States)

    Jin, Xin; Zhang, Zhen-Hai; Zhu, Jing; Sun, E; Yu, Dan-Hong; Chen, Xiao-Yun; Liu, Qi-Yuan; Ning, Qing; Jia, Xiao-Bin

    2012-04-01

    This article reports that nano-silica solid dispersion technology was used to raise genistein efficiency through increasing the enzymatic hydrolysis rate. Firstly, genistin-nano-silica solid dispersion was prepared by solvent method. And differential scanning calorimetry (DSC) and transmission electron microscopy (TEM) were used to verify the formation of solid dispersion, then enzymatic hydrolysis of solid dispersion was done by snailase to get genistein. With the conversion of genistein as criteria, single factor experiments were used to study the different factors affecting enzymatic hydrolysis of genistin and its solid dispersion. And then, response surface method was used to optimize of nano-silica solid dispersion technology assistant enzymatic hydrolysis. The optimum condition to get genistein through enzymatic hydrolysis of genistin-nano-silica solid dispersion was pH 7.1, temperature 52.2 degrees C, enzyme concentration 5.0 mg x mL(-1) and reaction time 7 h. Under this condition, the conversion of genistein was (93.47 +/- 2.40)%. Comparing with that without forming the genistin-nano-silica solid dispersion, the conversion increased 2.62 fold. At the same time, the product of hydrolysis was purified to get pure genistein. The method of enzymatic hydrolysis of genistin-nano-silica solid dispersion by snailase to obtain genistein is simple, efficiency and suitable for the modern scale production.

  7. Structural changes in lignin during organosolv pretreatment of Liriodendron tulipifera and the effect on enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Koo, Bon-Wook; Min, Byeong-Cheol; Gwak, Ki-Seob; Lee, Soo-Min; Choi, Joon-Weon; Yeo, Hwanmyeong; Choi, In-Gyu

    2012-01-01

    Although organosolv pretreatment removed substantial amounts of lignin and xylan, the yield of glucan which is a major sugar source for fermentation to ethanol is more than 90% in most conditions of the organosolv pretreatment. Relative lignin contents of all pretreated biomass were more than 200 g kg −1 , however enzymatic conversions were increased dramatically comparing to untreated biomass. Therefore the correlation between lignin and enzymatic hydrolysis could not be explained just by lignin content, and other changes resulting from lignin removal affected enzymatic hydrolysis. Results on enzymatic conversion and sugar recovery suggested that the critical temperature improving enzymatic hydrolysis significantly was between 120 °C and 130 °C. Microscopic analysis using Field emission scanning electron microscopy (FE-SEM) showed that structural lignin changes happened through organosolv pretreatment. Lignins were isolated from lignin carbohydrate complex (LCC) at the initial stage and then migrated to the surface of biomass. The isolated and migrated lignins were finally redistributed onto surface. These structural changes formed droplets on surface and increased pore volume in pretreated biomass. The increase in pore volume also increased available surface area and enzyme adsorption at initial stage, and thus enzymatic conversion increased significantly through organosolv pretreatment. It was verified that the droplets were mainly composed of lignin and the lignin droplets inhibited enzymatic hydrolysis through adsorption with cellulase. -- Highlights: ► Just lignin contents cannot explain a correlation with enzymatic hydrolysis. ► Several changes resulted from lignin removal must affect enzymatic hydrolysis. ► Droplets are formed by structural changes in lignin during organosolv pretreatment. ► Formation of the lignin droplet increases the pore volume in biomass. ► The increase in pore volume enhances the enzymatic hydrolysis.

  8. Production of Fish Hydrolysates Protein From Waste of Fish Carp (Cyprinus Carpio by Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Dede Saputra

    2016-03-01

    Full Text Available Fish Protein Hydrolysates (FPH is the mixed products of polypeptide, dipeptides, and amino acid. It can be produced from materials that contained of protein by acid reaction, base reaction or enzymatic hydrolysis. The objectives of this study were to study the production of FPH from fish carp meat at post rigor phase and viscera by enzymatic hydrolysis, to determine the specific activity of papain enzyme, and to determine the solubility of FPH. Capacity of fish hydrolyzing can be identified by analyzing the content of dissolved total nitrogen (NTT compared with nitrogen total ingredient (NTB in order to get the value of total soluble nitrogen/total nitrogen material (NTT/NTB. The hydrolysis processes were carried out in 0,26% (w/v papain, 60 οC for 3 hours. The result showed that the specific activity of papain enzyme was about 3.28 U/mg. Solubility of FPH by comparing NTT/NTB was about 0.29% (fish meat and 0.40% (fish viscera. Proximate test of protein content of fish meat was 18.34 ± 0.04 (g/100 g; while viscera was about 0.95±0.04 (g/100 g. The result indicated that product waste of fish carp had potential as a major of source of FPH.

  9. Switchgrass storage effects on the recovery of carbohydrates after liquid hot water pretreatment and enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Danielle Julie Carrier

    2016-08-01

    Full Text Available Perennial grasses that would be used for bioenergy and bioproducts production will need to be stored for various periods of time to ensure a continual feedstock supply to a bioprocessing facility. The effects of storage practices on grass composition and the response of grasses to subsequent bioprocesses such as pretreatment and enzymatic hydrolysis needs to be understood to develop the most efficient storage protocols. This study examined the effect of outdoor storage of round switchgrass bales on composition before and after liquid hot water pretreatment (LHW and enzymatic hydrolysis. This study also examined the effect of washing LHW pretreated biomass prior to enzymatic hydrolysis. It was determined that switchgrass composition after baling was stable. As expected, glucan and lignin contents increased after LHW due to decreases in xylan and galactan. Washing biomass prior to enzymatic hydrolysis reduced saccharification, especially in samples from the interior of the bale, by at least 5%.

  10. Alteration of biomass composition in response to changing substrate particle size and the consequences for enzymatic hydrolysis of corn bran

    DEFF Research Database (Denmark)

    Agger, Jane; Meyer, Anne S.

    2012-01-01

    Corn bran is a by-product from corn starch processing. This work examined the effects of changing substrate particle size on enzymatic hydrolysis of both raw and pretreated destarched corn bran. The biomass composition of the corn bran varied between particle size fractions: The largest particles...

  11. A Sequential Combination of Laccase Pretreatment and Enzymatic Hydrolysis for Glucose Production from Furfural Residues

    Directory of Open Access Journals (Sweden)

    Hailong Yu

    2014-06-01

    Full Text Available Furfural residues (FRs were pretreated with laccase or a laccase-mediator (1-hydroxybenzotriazole, HBT system to produce fermentable sugar for bioethanol production. Compared to laccase-only pretreatment, laccase-mediator pretreatment dissolved more lignin. Approximately 10.5% of the initially present lignin was removed when FRs were treated with a laccase loading of 100 U/g of dry substrate in 1% (w/w HBT at 48 °C for 24 h in an acetate buffer (pH 4.8. The enzymatic saccharification process was carried out by a combined laccase or laccase-mediator pretreatment without washing of the treated solids. The results showed that active laccase had a negative effect on the rate and yield of enzymatic hydrolysis. Laccase-oxidized HBT seriously reduced glucose yield. However, non-oxidized HBT increased glucose yield when laccase was deactivated at 121 °C for 20 min prior to enzymatic hydrolysis. The highest glucose yield, 80.9%, was obtained from the substrate pretreated with 100 U/g of dry substrate laccase and 1% (w/w HBT at 48 °C for 24 h in an acetate buffer (pH 4.8. Furthermore, the structures of FRs before and after laccase-mediator pretreatment were characterized by scanning electron microscopy (SEM and Fourier Transform Infrared spectroscopy (FT-IR.

  12. Mechano-Enzymatic Deconstruction with a New Enzymatic Cocktail to Enhance Enzymatic Hydrolysis and Bioethanol Fermentation of Two Macroalgae Species

    Directory of Open Access Journals (Sweden)

    Sameh Amamou

    2018-01-01

    Full Text Available The aim of this study was to explore the efficiency of a mechano-enzymatic deconstruction of two macroalgae species for sugars and bioethanol production, by using a new enzymatic cocktail (Haliatase and two types of milling modes (vibro-ball: VBM and centrifugal milling: CM. By increasing the enzymatic concentration from 3.4 to 30 g/L, the total sugars released after 72 h of hydrolysis increased (from 6.7 to 13.1 g/100 g TS and from 7.95 to 10.8 g/100 g TS for the green algae U. lactuca and the red algae G. sesquipedale, respectively. Conversely, total sugars released from G. sesquipedale increased (up to 126% and 129% after VBM and CM, respectively. The best bioethanol yield (6 geth/100 g TS was reached after 72 h of fermentation of U. lactuca and no increase was obtained after centrifugal milling. The latter led to an enhancement of the ethanol yield of G. sesquipedale (from 2 to 4 g/100 g TS.

  13. Production of Fish Hydrolysates Protein From Waste of Fish Carp (Cyprinus Carpio) by Enzymatic Hydrolysis

    OpenAIRE

    Saputra, Dede; Nurhayati, Tati

    2016-01-01

    Fish Protein Hydrolysates (FPH) is the mixed products of polypeptide, dipeptides, and amino acid. It can be produced from materials that contained of protein by acid reaction, base reaction or enzymatic hydrolysis. The objectives of this study were to study the production of FPH from fish carp meat at post rigor phase and viscera by enzymatic hydrolysis, to determine the specific activity of papain enzyme, and to determine the solubility of FPH. Capacity of fish hydrolyzing can be identified ...

  14. CONTINUOUS AND SEMICONTINUOUS REACTION SYSTEMS FOR HIGH-SOLIDS ENZYMATIC HYDROLYSIS OF LIGNOCELLULOSICS

    Directory of Open Access Journals (Sweden)

    A. González Quiroga

    2015-12-01

    Full Text Available Abstract An attractive operation strategy for the enzymatic hydrolysis of lignocellulosics results from dividing the process into three stages with complementary goals: continuous enzyme adsorption at low-solids loading (5% w/w with recycling of the liquid phase; continuous liquefaction at high-solids content (up to 20% w/w; and, finally, continuous or semicontinuous hydrolysis with supplementation of fresh enzymes. This paper presents a detailed modeling and simulation framework for the aforementioned operation strategies. The limiting micromixing situations of macrofluid and microfluid are used to predict conversions. The adsorption and liquefaction stages are modeled as a continuous stirred tank and a plug flow reactor, respectively. Two alternatives for the third stage are studied: a train of five cascading stirred tanks and a battery of batch reactors in parallel. Simulation results show that glucose concentrations greater than 100 g L-1 could be reached with both of the alternatives for the third stage.

  15. Optimization of fed-batch enzymatic hydrolysis from alkali-pretreated sugarcane bagasse for high-concentration sugar production.

    Science.gov (United States)

    Gao, Yueshu; Xu, Jingliang; Yuan, Zhenhong; Zhang, Yu; Liu, Yunyun; Liang, Cuiyi

    2014-09-01

    Fed-batch enzymatic hydrolysis process from alkali-pretreated sugarcane bagasse was investigated to increase solids loading, produce high-concentration fermentable sugar and finally to reduce the cost of the production process. The optimal initial solids loading, feeding time and quantities were examined. The hydrolysis system was initiated with 12% (w/v) solids loading in flasks, where 7% fresh solids were fed consecutively at 6h, 12h, 24h to get a final solids loading of 33%. All the requested cellulase loading (10 FPU/g substrate) was added completely at the beginning of hydrolysis reaction. After 120 h of hydrolysis, the maximal concentrations of cellobiose, glucose and xylose obtained were 9.376 g/L, 129.50 g/L, 56.03 g/L, respectively. The final total glucan conversion rate attained to 60% from this fed-batch process. Copyright © 2014. Published by Elsevier Ltd.

  16. Improved antimelanogenesis and antioxidant effects of polysaccharide from Cuscuta chinensis Lam seeds after enzymatic hydrolysis.

    Science.gov (United States)

    Liu, Zi-Jun; Wang, Ya-Lan; Li, Qi-Ling; Yang, Liu

    2018-01-01

    Cuscuta chinensis polysaccharide (CPS) was extracted using hot water and enzymatically hydrolyzed C. chinensis polysaccharide (ECPS) was produced by the mannase enzymatic hydrolysis process. The purpose of this research was to investigate the antimelanogenic activity of ECPS and CPS in B16F10 melanoma cells. The in vitro antioxidant activity was assessed by their ferric iron reducing power and DPPH free radical scavenging activities. The molecular mass distribution of polysaccharides was determined using SEC-MALLS-RI. CPS was successfully enzymatically degraded using mannase and the weighted average molecular weights of CPS and ECPS were 434.6 kDa and 211.7 kDa. The results of biological activity assays suggested that the enzymatically hydrolyzed polysaccharide had superior antimelanogenic activity and antioxidant effect than the original polysaccharide. ECPS exhibited antimelanogenic activity by down-regulating the expression of tyrosinase, MITF, and TRP-1 without cytotoxic effects in B16F10 melanoma cells. In conclusion, ECPS have the potential to become a skin whitening product.

  17. Selective ultrasound-enhanced enzymatic hydrolysis of oleuropein to its aglycon in olive (Olea europaea L.) leaf extracts.

    Science.gov (United States)

    Delgado-Povedano, María Del Mar; Priego-Capote, Feliciano; Luque de Castro, María Dolores

    2017-04-01

    Hydrolysis of oleuropein, the main phenol in olive (Olea europaea L.) leaf extracts, to oleuropein aglycon and other subsequent products in the hydrolytic pathway can be catalyzed by different enzymes. Three of the most used hydrolases were assayed to catalyze the process, and β-glucosidase from Aspergillus niger was selected. Acceleration of the enzymatic hydrolysis by ultrasound (US) was studied using a Box-Behnken design (duty cycle, amplitude, cycle time) and an oleuropein standard, and the optimum US conditions for achieving maximum yield of oleuropein aglycon were 0.5s/s duty cycle, 50% amplitude and 45s cycle. The method was applied to obtain oleuropein aglycon from commercial and laboratory extracts from olive leaves, which may have a pharmacological use as deduced by its healthy properties. The kinetics of the US-assisted enzymatic hydrolysis was monitored by analysis of the target compounds using liquid chromatography-tandem mass spectrometry. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Improving enzymatic hydrolysis of industrial hemp (Cannabis sativa L.) by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Shin, Soo-Jeong [Chungbuk National University, Cheongju, Chungbuk 361-763 (Korea, Republic of); Sung, Yong Joo [KT and G Central Research Institute, 302 Shinseong-Dong, Yuseong-Gu, Daejeon 305-805 (Korea, Republic of)], E-mail: yosung17@yahoo.co.kr

    2008-09-15

    The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of hemp biomass with doses of 150, 300 and 450 kGy. The higher irradiation dose resulted in the more extraction with hot-water extraction or 1% sodium hydroxide solution extraction. The higher solubility of the treated sample was originated from the chains scission during irradiation, which was indirectly demonstrated by the increase of carbonyl groups as shown in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra. The changes in the micro-structure of hemp resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The improvement in enzymatic hydrolysis by the irradiation was more evident in the hydrolysis of the xylan than in that of the cellulose.

  19. Improving enzymatic hydrolysis of industrial hemp (Cannabis sativa L.) by electron beam irradiation

    International Nuclear Information System (INIS)

    Shin, Soo-Jeong; Sung, Yong Joo

    2008-01-01

    The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of hemp biomass with doses of 150, 300 and 450 kGy. The higher irradiation dose resulted in the more extraction with hot-water extraction or 1% sodium hydroxide solution extraction. The higher solubility of the treated sample was originated from the chains scission during irradiation, which was indirectly demonstrated by the increase of carbonyl groups as shown in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra. The changes in the micro-structure of hemp resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The improvement in enzymatic hydrolysis by the irradiation was more evident in the hydrolysis of the xylan than in that of the cellulose

  20. Improving enzymatic hydrolysis of industrial hemp ( Cannabis sativa L.) by electron beam irradiation

    Science.gov (United States)

    Shin, Soo-Jeong; Sung, Yong Joo

    2008-09-01

    The electron beam irradiation was applied as a pretreatment of the enzymatic hydrolysis of hemp biomass with doses of 150, 300 and 450 kGy. The higher irradiation dose resulted in the more extraction with hot-water extraction or 1% sodium hydroxide solution extraction. The higher solubility of the treated sample was originated from the chains scission during irradiation, which was indirectly demonstrated by the increase of carbonyl groups as shown in diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) spectra. The changes in the micro-structure of hemp resulted in the better response to enzymatic hydrolysis with commercial cellulases (Celluclast 1.5L and Novozym 342). The improvement in enzymatic hydrolysis by the irradiation was more evident in the hydrolysis of the xylan than in that of the cellulose.

  1. Improvements on enzymatic hydrolysis of human hair for illicit drug determination by gas chromatography/mass spectrometry.

    Science.gov (United States)

    Míguez-Framil, Martha; Moreda-Piñeiro, Antonio; Bermejo-Barrera, Pilar; López, Patricia; Tabernero, María Jesús; Bermejo, Ana María

    2007-11-15

    The use of ultrasound energy for accelerating the pronase E enzymatic hydrolysis of human hair for extracting illicit drugs has been novelty tested. The enzymatic extracts obtained after 30 min of sonication in an ultrasonic water bath were subjected to an optimized solid-phase extraction process, which involved a solution of 2.0% (v/v) acetic acid in methanol as eluting solution and concentration by N2 stream evaporation. A gas chromatography/mass spectrometry method was used to separate and determine cocaine, benzoylecgonine, codeine, morphine, and 6-monoacethylmorphine in 20 min. Variables affecting ultrasound-assisted pronase E hydrolysis such as hydrolysis temperature, hydrolysis time, enzyme concentration, catalyzer (1,4-dithiothreitol) concentration, ionic strength, pH, and ultrasound frequency were simultaneously evaluated by a Plackett-Burman design 2(8) PBD of resolution III. The most statistically significant variables were ionic strength and pH, which means that analyte extraction is mainly attributed to pronase E activity. The optimization or evaluation of all the factors has led to an accelerated pronase E hydrolysis of human hair, which can be completed in 30 min. Results have been found to be statistically similar to those obtained with conventional pronase E hydrolysis. The accelerated method was finally applied to several human hair samples from multidrug abusers.

  2. Optimizing the Isolation of Microfibrillated Bamboo in High Pressure Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    N. A. Sri Aprilia

    2015-07-01

    Full Text Available Bleached bamboo fiber was treated with a high pressure enzymatic hydrolysis (HPEH process in order to produce microfibrillated bamboo fiber (MBF. Mixture design of experiments was utilized to determine the optimal constituents of fiber, enzymes, and water for the HPEH process on the isolation yield of the MBF. Results showed the optimal combination for the maximal yield isolation of the MBF was 1 g fiber, 1 g enzyme, and 1 L water at 90 MPa and 70 °C. The influence of the reaction time of the HPEH process (6 to 48 h was also evaluated in this study. Morphological and thermal property analyses of untreated and treated bamboo fibers revealed that the HPEH process was effective for removing non-cellulosic components from the fibers. Thus, the HPEH process is an effective method for the isolation of the MBF, with the benefits of elevated crystallinity and thermal stability.

  3. Enhanced enzymatic hydrolysis and ethanol production from cashew apple bagasse pretreated with alkaline hydrogen peroxide.

    Science.gov (United States)

    da Costa, Jessyca Aline; Marques, José Edvan; Gonçalves, Luciana Rocha Barros; Rocha, Maria Valderez Ponte

    2015-03-01

    The effect of combinations and ratios between different enzymes has been investigated in order to assess the optimal conditions for hydrolysis of cashew apple bagasse pretreated with alkaline hydrogen peroxide (the solids named CAB-AHP). The separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) processes were evaluated in the ethanol production. The enzymatic hydrolysis conducted with cellulase complex and β-glucosidase in a ratio of 0.61:0.39, enzyme loading of 30FPU/g(CAB-AHP) and 66CBU/g(CAB-AHP), respectively, using 4% cellulose from CAB-AHP, turned out to be the most effective conditions, with glucose and xylose yields of 511.68 mg/g(CAB-AHP) and 237.8 mg/g(CAB-AHP), respectively. Fermentation of the pure hydrolysate by Kluyveromyces marxianus ATCC 36907 led to an ethanol yield of 61.8kg/ton(CAB), corresponding to 15 g/L ethanol and productivity of 3.75 g/( Lh). The ethanol production obtained for SSF process using K. marxianus ATCC 36907 was 18 g/L corresponding to 80% yield and 74.2kg/ton(CAB). Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Phosphoric acid pretreatment of Achyranthes aspera and Sida acuta weed biomass to improve enzymatic hydrolysis.

    Science.gov (United States)

    Siripong, Premjet; Duangporn, Premjet; Takata, Eri; Tsutsumi, Yuji

    2016-03-01

    Achyranthes aspera and Sida acuta, two types of weed biomass are abundant and waste in Thailand. We focus on them as novel feedstock for bio-ethanol production because they contain high-cellulose content (45.9% and 46.9%, respectively) and unutilized material. Phosphoric acid (70%, 75%, and 80%) was employed for the pretreatment to improve by enzymatic hydrolysis. The pretreatment process removed most of the xylan and a part of the lignin from the weeds, while most of the glucan remained. The cellulose conversion to glucose was greater for pretreated A. aspera (86.2 ± 0.3%) than that of the pretreated S. acuta (82.2 ± 1.1%). Thus, the removal of hemicellulose significantly affected the efficiency of the enzymatic hydrolysis. The scanning electron microscopy images showed the exposed fibrous cellulose on the cell wall surface, and this substantial change of the surface structure contributed to improving the enzyme accessibility. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Sweetening syrup production by enzymatic hydrolysis of starch variety yam (Dioscorea rotundata

    Directory of Open Access Journals (Sweden)

    Carlos Ramón Vidal Tovar

    2011-04-01

    Full Text Available Sweeteners syrups produced by enzymatic hydrolysis from starch of hawthorn yam (Dioscorea rotundata. The starch was extracted by a scratched, washed, sedimented and drying; the yield was quantified taking into account the amount of initial raw material and was determined the concentration of starch, amylose, amylopectin, crude fiber, ash, protein, fat and humidity in accordance with the requirements of the AOAC standards, and ICONTEC COVENIN. Enzymatic hydrolysis of starch was conducted using ∂-amylase, glucoamylase and pullulanase in starch solutions at 36 and 46 % w/w varying the order of application of glucoamylase and pullulanase were determined pH, Brix, moisture, reducing sugars (AR, total sugar (TS and the dextrose equivalent (ED in the syrups obtained. In the liquefaction were obtained with an intermediate syrups sweeteners ED 18.81% and 22.15%. Syrups low and medium conversion with an ED between 34-45% in the first saccharification and high conversion syrups with a DE between 75-79% as a final product. The above values allow the use of hawthorn yam starch syrup production for multiple uses in different food industry processes.

  6. Feasibility of reusing the black liquor for enzymatic hydrolysis and ethanol fermentation.

    Science.gov (United States)

    Wang, Wen; Chen, Xiaoyan; Tan, Xuesong; Wang, Qiong; Liu, Yunyun; He, Minchao; Yu, Qiang; Qi, Wei; Luo, Yu; Zhuang, Xinshu; Yuan, Zhenhong

    2017-03-01

    The black liquor (BL) generated in the alkaline pretreatment process is usually thought as the environmental pollutant. This study found that the pure alkaline lignin hardly inhibited the enzymatic hydrolysis of cellulose (EHC), which led to the investigation on the feasibility of reusing BL as the buffer via pH adjustment for the subsequent enzymatic hydrolysis and fermentation. The pH value of BL was adjusted from 13.23 to 4.80 with acetic acid, and the alkaline lignin was partially precipitated. It deposited on the surface of cellulose and negatively influenced the EHC via blocking the access of cellulase to cellulose and adsorbing cellulase. The supernatant separated from the acidified BL scarcely affected the EHC, but inhibited the ethanol fermentation. The 4-times diluted supernatant and the last-time waste wash water of the alkali-treated sugarcane bagasse didn't inhibit the EHC and ethanol production. This work gives a clue of saving water for alkaline pretreatment. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Tissue-specific biomass recalcitrance in corn stover pretreated with liquid hot-water: enzymatic hydrolysis (part 1).

    Science.gov (United States)

    Zeng, Meijuan; Ximenes, Eduardo; Ladisch, Michael R; Mosier, Nathan S; Vermerris, Wilfred; Huang, Chia-Ping; Sherman, Debra M

    2012-02-01

    Lignin content, composition, distribution as well as cell wall thickness, structures, and type of tissue have a measurable effect on enzymatic hydrolysis of cellulose in lignocellulosic feedstocks. The first part of our work combined compositional analysis, pretreatment and enzyme hydrolysis for fractionated pith, rind, and leaf tissues from a hybrid stay-green corn, in order to identify the role of structural characteristics on enzyme hydrolysis of cell walls. The extent of enzyme hydrolysis follows the sequence rind cellulose to glucose in 24 h in the best cases. Physical fractionation of corn stalks or other C(4) grasses into soft and hard tissue types could reduce cost of cellulose conversion by enabling reduced enzyme loadings to hydrolyze soft tissue, and directing the hard tissue to other uses such as thermal processing, combustion, or recycle to the land from which the corn was harvested. Copyright © 2011 Wiley Periodicals, Inc.

  8. Enzymatic hydrolysis of Amaranth flour - differential scanning calorimetry and scanning electron microscopy studies

    Energy Technology Data Exchange (ETDEWEB)

    Barba de la Rosa, A.P.; Paredes-Lopez, O.; Carabez-Trejo, A.; Ordorica-Falomir, C. (Instituto Politecnico Nacional, Irapuato (Mexico). Centro de Investigacion y de Estudios Avanzados)

    1989-11-01

    High-protein amaranth flour (HPAF) and carbohydrate rich fraction (CRF) were produced from raw flour in a single-step process using a heat-stable alpha-amylase preparation. Protein content of flour increased from 15 to about 30 or 39% at liquefaction temperatures of 70 or 90{sup 0}C, respectively and 30 min hydrolysis time. CRF exhibited 14-22 DE. Enzymatic action at 70{sup 0}C increased endotherm temperature and gelatinization enthalpy of HPAF, in relation to gelatinized flour, as assessed by differential scanning calorimetry (DSC). Hydrolysis at 90{sup 0}C did not affect significantly (P > 0.05) DSC peak temperature. It is suggested that these changes in DSC performance might result from differences in amount and type of low-molecular weight carbohydrates and residual starch. Scanning electron microscopy (SEM) demonstrated that hydrolysis temperature changed substantially the structural appearance of flour particles. HPAF and CRF might find applications as dry milk extender and sweetener, respectively. (orig.).

  9. Bioethanol Production By Utilizing Cassava Peels Waste Through Enzymatic And Microbiological Hydrolysis

    Science.gov (United States)

    Witantri, R. G.; Purwoko, T.; Sunarto; Mahajoeno, E.

    2017-07-01

    Cassava peels waste contains, cellulose which is quite high at 43.626%, this is a potential candidate as a raw for bioethanol production. The purpose of this study was to determine the performance of the enzymatic hydrolysis, microbiological (Effective microbe) and fermentation in cassava peel waste is known from the results of quantitative measurement of multiple ethanol parameters (DNS Test, pH, ethanol concentration). This research was carried out in stages, the first stage is hydrolysis with completely randomized design with single factor variation of the catalyst, consisting of three levels ie cellulase enzymes, multienzyme and effective microbial EM4. The second stage is fermentation with factorial randomized block design, consisting of three groups of variations of catalyst, and has two factors: variations of fermipan levels 1, 2, 3% and the duration of fermentation, 2,4,6 days. The parameters in the test is a reducing sugar, pH and concentration of ethanol. The results showed that variation of hydrolysis treatment, fermentation time, and fermipan levels has real effect on the fermentation process. On average the highest ethanol content obtained from the treatment with multienzyme addition, with the addition of 2% fermipan levels and on the 2nd day of fermentation that is equal to 3.76%.

  10. Enzymatic hydrolysis of cellulose dissolved in N-methyl morpholine oxide/water solutions.

    Science.gov (United States)

    Ramakrishnan, S; Collier, J; Oyetunji, R; Stutts, B; Burnett, R

    2010-07-01

    In situ hydrolysis of cellulose (dissolving pulp) in N-methyl morpholine oxide (NMMO) solutions by commercially available Accellerase1000 is carried out. The yield of reducing sugars is followed as a function of time at three different temperatures and four different enzyme loadings to study the effect of system parameters on enzymatic hydrolysis. Initial results show that rates of hydrolysis of cellulose and yields of reducing sugars in the presence of NMMO-water is superior initially (ratio of initial reaction rates approximately 4) and comparable to that of regenerated cellulose (for times greater than 5h) when suspended in aqueous solutions. The usage of Accellerase1000 results predominantly in the formation of glucose with minimal amounts of cellobiose. This study proves the ability of cellulases to remain active in NMMO to carry out an in situ saccharification of cellulose thus eliminating the need to recover regenerated cellulose. Thus this work will form the basis for developing a continuous process for conversion of biomass to hydrogen, ethanol and other hydrocarbons. Copyright 2009 Elsevier Ltd. All rights reserved.

  11. Cross-synergism in enzymatic hydrolysis of lignocellulosics: mathematical correlations according to a hyperbolic model

    Energy Technology Data Exchange (ETDEWEB)

    Tarantili, P.A.; Koullas, D.P.; Christakopoulos, P.; Kekos, D.; Koukios, E.G.; Macris, B.J. [National Technical Univ. of Athens (Greece). Dept. of Chemical Engineering

    1996-10-01

    The effect of cross-synergism in enzymatic hydrolysis of ball-milled Avicell, alkali-treated straw cellulose (ATSC), cotton and filter paper was investigated using mixtures of Fusarium oxysporum and Neurospora crassa enzymes. The experimental data were fitted according to an empirical hyperbolic model which utilized two parameters, the maximum conversion ({chi}{sub max}) and the enzymatic hydrolysis time corresponding to 50% of {chi}{sub max} (t{sub 1/2}). The model can predict conversion of polysaccharides as a function of hydrolysis time. Both model parameters were found to be strongly dependent on the crystallinity index as well as on the degree of delignification of the substrate. Up to 60% cellulose hydrolysis can be achieved when the crystallinity index of Avicell is reduced from 94.8% to 63.3%. The percentage increase of {chi}{sub max} due to delignification was higher than the corresponding increase of t{sub 1/2}. The extent of cross-synergism depends strongly on crystallinity index and degree of delignification. This type of synergism has been found to be significant in the case of substrates which are resistant to hydrolysis, such as Avicell (with high crystallinity index) or cotton. Cross-synergism phenomena caused by enzymatic mixtures can double cellulose hydrolysis yield with delignified straw as compared to the hydrolysis yields achieved by single-microorganism cellulases. (author)

  12. Ethanol production from cashew apple bagasse: improvement of enzymatic hydrolysis by microwave-assisted alkali pretreatment.

    Science.gov (United States)

    Rodrigues, Tigressa Helena Soares; Rocha, Maria Valderez Ponte; de Macedo, Gorete Ribeiro; Gonçalves, Luciana R B

    2011-07-01

    In this work, the potential of microwave-assisted alkali pretreatment in order to improve the rupture of the recalcitrant structures of the cashew able bagasse (CAB), lignocellulosic by-product in Brazil with no commercial value, is obtained from cashew apple process to juice production, was studied. First, biomass composition of CAB was determined, and the percentage of glucan and lignin was 20.54 ± 0.70% and 33.80 ± 1.30%, respectively. CAB content in terms of cellulose, hemicelluloses, and lignin, 19.21 ± 0.35%, 12.05 ± 0.37%, and 38.11 ± 0.08%, respectively, was also determined. Results showed that, after enzymatic hydrolysis, alkali concentration exerted influence on glucose formation, after pretreatment with 0.2 and 1.0 mo L(-1) of NaOH (372 ± 12 and 355 ± 37 mg g(glucan)(-1) ) when 2% (w/v) of cashew apple bagasse pretreated by microwave-assisted alkali pretreatment (CAB-M) was used. On the other hand, pretreatment time (15-30 min) and microwave power (600-900 W) exerted no significant effect on hydrolysis. On enzymatic hydrolysis step, improvement on solid percentage (16% w/v) and enzyme load (30 FPU g (CAB-M) (-1) ) increased glucose concentration to 15 g L(-1). The fermentation of the hydrolyzate by Saccharomyces cerevesiae resulted in ethanol concentration and productivity of 5.6 g L(-1) and 1.41 g L(-1) h(-1), respectively.

  13. Effect of mixing on enzymatic hydrolysis of steam-pretreated spruce: a quantitative analysis of conversion and power consumption

    Directory of Open Access Journals (Sweden)

    Wiman Magnus

    2011-05-01

    Full Text Available Abstract Background When scaling up lignocellulose-based ethanol production, the desire to increase the final ethanol titer after fermentation can introduce problems. A high concentration of water-insoluble solids (WIS is needed in the enzymatic hydrolysis step, resulting in increased viscosity, which can cause mass and heat transfer problems because of poor mixing of the material. In the present study, the effects of mixing on the enzymatic hydrolysis of steam-pretreated spruce were investigated using a stirred tank reactor operated with different impeller speeds and enzyme loadings. In addition, the results were related to the power input needed to operate the impeller at different speeds, taking into account the changes in rheology throughout the process. Results A marked difference in hydrolysis rate at different impeller speeds was found. For example, the conversion was twice as high after 48 hours at 500 rpm compared with 25 rpm. This difference remained throughout the 96 hours of hydrolysis. Substantial amounts of energy were required to achieve only minor increases in conversion during the later stages of the process. Conclusions Impeller speed strongly affected both the hydrolysis rate of the pretreated spruce and needed power input. Similar conversions could be obtained at different energy input by altering the mixing (that is, energy input, enzyme load and residence time, an important issue to consider when designing large-scale plants.

  14. Enzymatic hydrolysis and ethanol fermentation of high dry matter wet-exploded wheat straw at low enzyme loading

    DEFF Research Database (Denmark)

    Georgieva, T.I.; Hou, Xiaoru; Hilstrøm, Troels

    2008-01-01

    was the most efficient in enhancing overall convertibility of the raw material to sugars and minimizing generation of furfural as a by-product. For scale-up of the process, high dry matter (DM) concentrations of 15-20% will be necessary. However, high DM hydrolysis and fermentation are limited by high...... and a low enzyme loading of 10 FPU/g cellulose in an industrial acceptable time frame of 96 h. Cellulose and hemicellulose conversion from enzymatic hydrolysis were 70 and 68%, respectively, and an overall ethanol yield from SSF was 68%....

  15. Enzymatic activity of the cellulolytic complex produced by Trichoderma reesei. Enzymatic hydrolysis of cellulose; Actividad enzimatica del complejo celulolitico producido por Trichoderma reesei. Hidrolisis enzimatica de la celulosa

    Energy Technology Data Exchange (ETDEWEB)

    Alfonsel, M; Negro, M J; Saez, R; Martin, C

    1986-07-01

    The enzymatic activity characterization of the cellulolytic complex obtained from Trichoderma reesei QM 9414 and the influence of the enzymatic hydrolysis conditions on the hydrolysis yield are studied. Pure cellulose and native or alkali pretreated biomass Onopordum nervosum have been used as substrates. The values of pH, temperature, substrate concentration and enzyme-substrate ratio for the optimum activity of that complex, evaluated as glucose and reducing sugars production, have been selected. Previous studies on enzymatic hydrolysis of 0. nervosum have shown a remarkable effect of the alkaline pretreatments on the final hydrolysis yield. (Author) 10 refs.

  16. Enteral Tube Feeding Nutritional Protein Hydrolysate Production Under Different Factors By Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Nguyen ThiQuynhHoa

    2015-01-01

    Full Text Available Abstract Hydrolysis of proteins involves the cleavage of peptide bonds to give peptides of varying sizes and amino acid composition. There are a number of types of hydrolysis enzymatic acid or alkali hydrolysis. Chemical hydrolysis is difficult to control and reduces the nutritional quality of products destroying L-form amino acids and producing toxic substances such as lysino-alanine. Enzymatic hydrolysis works without destructing amino acids and by avoiding the extreme temperatures and pH levels required for chemical hydrolysis the nutritional properties of the protein hydrolysates remain largely unaffected. In this research we investigate the fat removal and protein hydrolysis from pork meat to produce the enteral tube feeding nutritional protein hydrolysate for patient. Our results are as follows meat moisture 75.1 protein 22.6 lipid 1.71 ash 0.5 vitamin B1 1.384mg100g n hexantreatment at 80oCin 45 minutes and drying 30 minutes in 90oC.Viscosity of the hydrolysate is very low 2.240 0.092 cPand high degree of hydrolysis 31.390 0.138 . The final protein powder has balance nutritional components and acid amines low microorganisms which are safety for human consumption.

  17. ENZYMATIC HYDROLYSIS OF SWITCHGRASS AND COASTAL BERMUDA GRASS PRETREATED USING DIFFERENT CHEMICAL METHODS

    Directory of Open Access Journals (Sweden)

    Jiele Xu

    2011-06-01

    Full Text Available To investigate the effects of biomass feedstock and pretreatment method on the enzyme requirement during hydrolysis, swichgrass and coastal Bermuda grass pretreated using H2SO4, NaOH, and Ca(OH2 at the optimal conditions were subjected to enzymatic hydrolysis using two enzyme combinations: NS 50013 + NS 50010 and Cellic CTec + Cellic HTec. The enzyme loadings were optimized, and correlations between feedstock property, pretreatment strategy, and enzyme usage were evaluated. The results show that pretreatment methods resulting in greater lignin contents in the pretreated biomass were generally associated with higher enzyme requirements. More sugars could be recovered from alkaline-pretreated biomass during enzymatic hydrolysis due to the better carbohydrate preservation achieved at mild pretreatment temperatures. The cellulase enzyme, Cellic CTec, was more efficient in catalyzing the hydrolysis of coastal Bermuda grass, a feedstock more digestible than the pretreated swichgrass, following pretreatment with NaOH or Ca(OH2.

  18. Assessment of antioxidant and antimicrobial properties of lignin from corn stover residue pretreated with low-moisture anhydrous ammonia and enzymatic hydrolysis process

    Science.gov (United States)

    To improve the economic viability of biofuel production from biomass resources, it is increasingly important to develop value-added lignin co-products from this process. The main objective of this study was to investigate the antimicrobial and antioxidant activities of the lignin extracts obtained b...

  19. Mechanistic kinetic models of enzymatic cellulose hydrolysis-A review.

    Science.gov (United States)

    Jeoh, Tina; Cardona, Maria J; Karuna, Nardrapee; Mudinoor, Akshata R; Nill, Jennifer

    2017-07-01

    Bioconversion of lignocellulose forms the basis for renewable, advanced biofuels, and bioproducts. Mechanisms of hydrolysis of cellulose by cellulases have been actively studied for nearly 70 years with significant gains in understanding of the cellulolytic enzymes. Yet, a full mechanistic understanding of the hydrolysis reaction has been elusive. We present a review to highlight new insights gained since the most recent comprehensive review of cellulose hydrolysis kinetic models by Bansal et al. (2009) Biotechnol Adv 27:833-848. Recent models have taken a two-pronged approach to tackle the challenge of modeling the complex heterogeneous reaction-an enzyme-centric modeling approach centered on the molecularity of the cellulase-cellulose interactions to examine rate limiting elementary steps and a substrate-centric modeling approach aimed at capturing the limiting property of the insoluble cellulose substrate. Collectively, modeling results suggest that at the molecular-scale, how rapidly cellulases can bind productively (complexation) and release from cellulose (decomplexation) is limiting, while the overall hydrolysis rate is largely insensitive to the catalytic rate constant. The surface area of the insoluble substrate and the degrees of polymerization of the cellulose molecules in the reaction both limit initial hydrolysis rates only. Neither enzyme-centric models nor substrate-centric models can consistently capture hydrolysis time course at extended reaction times. Thus, questions of the true reaction limiting factors at extended reaction times and the role of complexation and decomplexation in rate limitation remain unresolved. Biotechnol. Bioeng. 2017;114: 1369-1385. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  20. Enzymatic Hydrolysis of Pretreated Fibre Pressed Oil Palm Frond by using Sacchariseb C6

    Science.gov (United States)

    Hashim, F. S.; Yussof, H. W.; Zahari, M. A. K. M.; Rahman, R. A.; Illias, R. M.

    2017-06-01

    Enzymatic hydrolysis becomes a prominent technology for conversion of cellulosic biomass to its glucose monomers that requires an action of cellulolytic enzymes in a sequential and synergistic manner. In this study, the effect of agitation speed, glucan loading, enzyme loading, temperature and reaction time on the production of glucose from fibre pressed oil palm frond (FPOPF) during enzymatic hydrolysis was screened by a half factorial design 25-1 using Response Surface Methodology (RSM). The FPOPF sample was first delignified by alkaline pretreatment at 4.42 (w/v) sodium hydroxide for an hour prior to enzymatic hydrolysis using commercial cellulase enzyme, Sacchariseb C6. The effect of enzymatic hydrolysis on the structural of FPOPF has been evaluated by Scanning Electron Microscopy (SEM) analysis. Characterization of raw FPOPF comprised of 4.5 extractives, 40.7 glucan, 26.1 xylan, 26.2 lignin and 1.8 ash, whereas for pretreated FPOPF gave 0.3 extractives, 61.4 glucan, 20.4 xylan, 13.3 lignin and 1.3 ash. From this study, it was found that the best enzymatic hydrolysis condition yielded 33.01 ± 0.73 g/L of glucose when performed at 200 rpm of agitation speed, 60 FPU/mL of enzyme loading, 4 (w/w) of glucan loading, temperature at 55 □ and 72 hours of reaction time. The model obtained was significant with p-value enzymatic hydrolysis from pretreated FPOPF produce high amount of glucose that enhances it potential for industrial application. This glucose can be further used to produce high-value products.

  1. The Mechanisms of Plant Cell Wall Deconstruction during Enzymatic Hydrolysis

    DEFF Research Database (Denmark)

    Thygesen, Lisbeth Garbrecht; E. Thybring, Emil; Johansen, Katja Salomon

    2014-01-01

    . Here we put forward a simple model based on mechanical principles capable of capturing the result of the interaction between mechanical forces and cell wall weakening via hydrolysis of glucosidic bonds. This study illustrates that basic material science insights are relevant also within biochemistry...

  2. Chemical and enzymatic hydrolysis of anthraquinone glycosides from Madder roots

    NARCIS (Netherlands)

    Derksen, G.C.H.; Naayer, M.; Beek, T.A. van; Capelle, A.; Haaksman, I.K.; Doren, H.A. van; Groot, Æ. de

    2003-01-01

    For the production of a commercially useful dye extract from madder, the glycoside ruberythric acid has to be hydrolysed to the aglycone alizarin which is the main dye component. An intrinsic problem is the simultaneous hydrolysis of the glycoside lucidin pritneveroside to the unwanted mutagenic

  3. Radiation pretreatments of cellulose materials for the enhancement of enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Ait Si Mamar, S.; Hadjadj, A.

    1990-01-01

    The conversion of wheat straw agricultural cellulosic wastes to reducing sugars and glucose has been studied by pretreatments by acid hydrolysis and gamma radiolysis over the dose 0-2 MGy. The pretreatment of cellulosic wastes by gamma radiolysis in the presence of sulfuric acid solution shows that the reducing sugars yield increases with the irradiation dose. The effect of radiation degradation on cellulosic wastes between 0.1 MGy and 2 MGy shows the glucose and reducing sugars yields after enzymatic hydrolysis by cellulase vary with the dose. In the relatively low dose range, up to about 0.5 MGy, the reducing sugars yields vary slightly. For an acid hydrolysis followed by radiation at dose range below 0.5 MGy the reducing sugars yields are practically insensitive to radiation. On the other hand, the pretreatment by radiation in higher dose range from 0.5 to 2 MGy followed by enzymatic hydrolysis is effective for the conversion of cellulosic wastes into glucose. The radiation induced degradation of cellulose into glucose depends on the type of acid hydrolysis and on the enzymatic hydrolysis time by cellulase. Pre-irradiation in air is more effective than in acid solution. (author)

  4. Radiation pretreatments of cellulose materials for the enhancement of enzymatic hydrolysis

    Science.gov (United States)

    Mamar, S. Ait Si; Hadjadj, A.

    The conversion of wheat straw agricultural cellulosic wastes to reduning sugars and glucose has been studied by pretreatments by acid hydrolysis and gamma radiolysis over the dose 0-2 MGy. The pretreatment of cellulosic wastes by gamma radiolysis in the presence of sulfuric acid solution shows that the reducing sugars yield increases with the irradiation dose. The effect of radiation degradation on cellulosic wastes between 0.1 MGy and 2 MGy shows the glucose and reducing sugars yields after enzymatic hydrolysis by cellulase vary with the dose. In the relatively low dose range, up to about 0.5 MGy, the reducing sugars yields vary slightly. For an acid hydrolysis followed by radiation at dose range below 0.5 MGy the reducing sugars yields are practically insensitive to radiation. On the other hand, the pretreatment by radiation in higher dose range from 0.5 to 2 MGy followed by enzymatic hydrolysis is effective for the conversion of cellulosic wastes into glucose. The radiation induced degradation of cellulose into glucose depends on the type of acid hydrolysis and on the enzymatic hydrolysis time by cellulase. Pre-irradiation in air is more effective than in acid solution.

  5. Cassava Pulp as a Biofuel Feedstock of an Enzymatic Hydrolysis Proces

    Directory of Open Access Journals (Sweden)

    Djuma’ali Djuma’ali

    2013-03-01

    Full Text Available Cassava pulp, a low cost solid byproduct of cassava starch industry, has been proposed as a high potential ethanolic fermentation substrate due to its high residual starch level, low ash content and small particle size of the lignocellulosic fibers. As the economic feasibility depends on complete degradation of the polysaccharides to fermentable glucose, the comparative hydrolytic potential of cassava pulp by six commercial enzymes were studied. Raw cassava pulp (12% w/v, particle size <320 μm hydrolyzed by both commercial pectinolytic (1 and amylolytic (2 enzymes cocktail, yielded 70.06% DE. Hydrothermal treatment of cassava pulp enhanced its susceptibility to enzymatic cleavageas compared to non-hydrothermal treatment raw cassava pulp. Hydrothermal pretreatment has shown that a glucoamylase (3 was the most effective enzyme for hydrolysis process of cassava pulp at temperature 65 °C or 95 °C for 10 min and yielded approximately 86.22% and 90.18% DE, respectively. Enzymatic pretreatment increased cassava pulp vulnerability to cellulase attacks. The optimum conditions for enzymatic pretreatment of 30% (w/v cassava pulp by a potent cellulolytic/ hemicellulolytic enzyme (4 was achieves at 50 °C for 3, meanwhile for liquefaction and saccharification by a thermo-stable α-amylase (5 was achieved at 95 °C for 1 and a glucoamylase (3 at 50 °C for 24 hours, respectively, yielded a reducing sugar level up to 94,1% DE. The high yield of glucose indicates the potential use of enzymatic-hydrothermally treated cassava pulp as a cheap substrate for ethanol production.

  6. Enzymatic hydrolysis (pepsin assisted by ultrasound in the functional Properties of hydrolyzates from different collagens

    Directory of Open Access Journals (Sweden)

    Alessandra Roseline Vidal

    2018-03-01

    Full Text Available ABSTRACT: Enzymatic hydrolysis (pepsin assisted with or without ultrasound in the functional properties of hydrolyzates from different collagens were analyzed. Degree of hydrolysis, antioxidant activity (DPPH and antimicrobial activity (MIC were assessed. The treatment that resulted in greater antioxidant activity for the fiber sample was with the use of 4% of enzyme and concomitant ultrasound (40.7%, leading to a degree of hydrolysis of 21.7%. For the powdered fiber sample the hydrolysis treatment with use of 4% of enzyme resulted in lower protein content (6.97mg/mL, higher degree of hydrolysis (19.9% and greater antioxidant activity (38.6%. The hydrolyzates showed inhibitory capacity against gram-negative bacteria Salmonella choleraesuis and gram-positive bacteria Staphylococcus aureus. It can be concluded that enzymatic hydrolysis concomitant or not with the use of ultrasound increased the functionality of the fiber and powdered fiber samples, for the other samples its use as supplementary treatment was not productive, due to the worse results of antioxidant activity (DPPH reported. However, it provided greater hydrolysis degree.

  7. Pretreatment of Eucalyptus in biphasic system for furfural production and accelerated enzymatic hydrolysis.

    Science.gov (United States)

    Zhang, Xiudong; Bai, Yuanyuan; Cao, Xuefei; Sun, Runcang

    2017-08-01

    Herein, an efficient biphasic pretreatment process was developed to improve the production of furfural (FF) and glucose from Eucalyptus. The influence of formic acid and NaCl on FF production from xylose in water and various biphasic systems was investigated. Results showed that the addition of formic acid and NaCl significantly promoted the FF yield, and the biphasic system of MIBK (methyl isobutyl ketone)/water exhibited the best performance for FF production. Then the Eucalyptus was pretreated in the MIBK/water system, and a maximum FF yield of 82.0% was achieved at 180°C for 60min. Surface of the pretreated Eucalyptus became relatively rough and loose, and its crystallinity index increased obviously due to the removal of hemicelluloses and lignin. The pretreated Eucalyptus samples showed much higher enzymatic hydrolysis rates (26.2-70.7%) than the raw Eucalyptus (14.5%). Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Study on the technology of compound enzymatic hydrolysis of whole passion fruit

    Science.gov (United States)

    Yang, Yu-xia; Duan, Zhen-hua; Kang, Chao; Zhu, Xiang-hao; Li, Ding-jin

    2017-12-01

    Fresh Whole Passion Fruit was used as raw material, The enzymatic hydrolysis technology of Passion Fruit by Complex enzyme were studied, The effects of enzyme dosage, Enzyme ratio(cellulose: pectinase), pH, temperature and time on the hydrolysis were investigated by single-tests and orthogonal tests, the hydrolysis indicators of single-factor tests and orthogonal tests were juice yield. The optimal hydrolysis conditions of Passion Fruit by Complex enzyme were enzyme dosage 0.12%, Enzyme ratio 5:1, hydrolysis temperature 50°C, pH4.0 and time 3.5 h. Under such conditions, juice yield of Passion Fruit was 92.91%.

  9. Effect of bovine serum albumin (BSA) on enzymatic cellulose hydrolysis.

    Science.gov (United States)

    Wang, Hui; Mochidzuki, Kazuhiro; Kobayashi, Shinichi; Hiraide, Hatsue; Wang, Xiaofen; Cui, Zongjun

    2013-06-01

    Bovine serum albumin (BSA) was added to filter paper during the hydrolysis of cellulase. Adding BSA before the addition of the cellulase enhances enzyme activity in the solution, thereby increasing the conversion rate of cellulose. After 48 h of BSA treatment, the BSA adsorption quantities are 3.3, 4.6, 7.8, 17.2, and 28.3 mg/g substrate, each with different initial BSA concentration treatments at 50 °C; in addition, more cellulase was adsorbed onto the filter paper at 50 °C compared with 35 °C. After 48 h of hydrolysis, the free-enzyme activity could not be measured without the BSA treatment, whereas the remaining activity of the filter paper activity was approximately 41 % when treated with 1.0 mg/mL BSA. Even after 96 h of hydrolysis, 25 % still remained. Meanwhile, after 48 h of incubation without substrate, the remaining enzyme activities were increased 20.7 % (from 43.7 to 52.7 %) and 94.8 % (from 23.3 to 45.5 %) at 35 and 50 °C, respectively. Moreover, the effect of the BSA was more obvious at 35 °C compared with 50 °C. When using 15 filter paper cellulase units per gram substrate cellulase loading at 50 °C, the cellulose conversion was increased from 75 % (without BSA treatment) to ≥90 % when using BSA dosages between 0.1 and 1.5 mg/mL. Overall, these results suggest that there are promising strategies for BSA treatment in the reduction of enzyme requirements during the hydrolysis of cellulose.

  10. Hydrothermal treatment followed by enzymatic hydrolysis and hydrothermal carbonization as means to valorise agro- and forest-based biomass residues.

    Science.gov (United States)

    Wikberg, Hanne; Grönqvist, Stina; Niemi, Piritta; Mikkelson, Atte; Siika-Aho, Matti; Kanerva, Heimo; Käsper, Andres; Tamminen, Tarja

    2017-07-01

    The suitability of several abundant but underutilized agro and forest based biomass residues for hydrothermal treatment followed by enzymatic hydrolysis as well as for hydrothermal carbonization was studied. The selected approaches represent simple biotechnical and thermochemical treatment routes suitable for wet biomass. Based on the results, the hydrothermal pre-treatment followed by enzymatic hydrolysis seemed to be most suitable for processing of carbohydrate rich corn leaves, corn stover, wheat straw and willow. High content of thermally stable components (i.e. lignin) and low content of ash in the biomass were advantageous for hydrothermal carbonization of grape pomace, coffee cake, Scots pine bark and willow. Copyright © 2017 Elsevier Ltd. All rights reserved.

  11. Structural features of dilute acid, steam exploded, and alkali pretreated mustard stalk and their impact on enzymatic hydrolysis.

    Science.gov (United States)

    Kapoor, Manali; Raj, Tirath; Vijayaraj, M; Chopra, Anju; Gupta, Ravi P; Tuli, Deepak K; Kumar, Ravindra

    2015-06-25

    To overcome the recalcitrant nature of biomass several pretreatment methodologies have been explored to make it amenable to enzymatic hydrolysis. These methodologies alter cell wall structure primarily by removing/altering hemicelluloses and lignin. In this work, alkali, dilute acid, steam explosion pretreatment are systematically studied for mustard stalk. To assess the structural variability after pretreatment, chemical analysis, surface area, crystallinity index, accessibility of cellulose, FT-IR and thermal analysis are conducted. Although the extent of enzymatic hydrolysis varies upon the methodologies used, nevertheless, cellulose conversion increases from adsorption capacity. However, no such relationship is observed for xylose yield. Mass balance of the process is also studied. Dilute acid pretreatment is the best methodology in terms of maximum sugar yield at lower enzyme loading. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Nanosilver: A Catalyst in Enzymatic Hydrolysis of Starch

    Directory of Open Access Journals (Sweden)

    Falkowska Marta

    2014-09-01

    Full Text Available Silver nanoparticles are widely used, because of their antimicrobial properties. In this paper, the rate of starch digestion in the presence of nanocatalyst was compared with the rate of reaction without nanosilver. The rate of enzymatic degradation of starch was found to be increased in the presence of silver nanoparticles. It is considered that α-amylase was immobilized onto the surface of nanoparticles.

  13. Lignin-based polyoxyethylene ether enhanced enzymatic hydrolysis of lignocelluloses by dispersing cellulase aggregates.

    Science.gov (United States)

    Lin, Xuliang; Qiu, Xueqing; Yuan, Long; Li, Zihao; Lou, Hongming; Zhou, Mingsong; Yang, Dongjie

    2015-06-01

    Water-soluble lignin-based polyoxyethylene ether (EHL-PEG), prepared from enzymatic hydrolysis lignin (EHL) and polyethylene glycol (PEG1000), was used to improve enzymatic hydrolysis efficiency of corn stover. The glucose yield of corn stover at 72h was increased from 16.7% to 70.1% by EHL-PEG, while increase in yield with PEG4600 alone was 52.3%. With the increase of lignin content, EHL-PEG improved enzymatic hydrolysis of microcrystalline cellulose more obvious than PEG4600. EHL-PEG could reduce at least 88% of the adsorption of cellulase on the lignin film measured by quartz crystal microbalance with dissipation monitoring (QCM-D), while reduction with PEG4600 was 43%. Cellulase aggregated at 1220nm in acetate buffer analyzed by dynamic light scattering. EHL-PEG dispersed cellulase aggregates and formed smaller aggregates with cellulase, thereby, reduced significantly nonproductive adsorption of cellulase on lignin and enhanced enzymatic hydrolysis of lignocelluloses. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Effective of Microwave-KOH Pretreatment on Enzymatic Hydrolysis of Bamboo

    Science.gov (United States)

    Zhiqiang Li; Zehui Jiang; Yan Yu; Zhiyong Cai

    2012-01-01

    Bamboo, with its advantages of fast growth, short renovation, easy propagation and rich in cellulose and hemicellulose, is a potential feedstock for bioethanol or other biofuels production. The objective of this study was to examine the fea- sibility of microwave assistant KOH pretreatments to enhance enzymatic hydrolysis of bamboo. Pretreatment was car- ried out by...

  15. Effects of Ionic Strength on the Enzymatic Hydrolysis of Diluted and Concentrated Whey Protein Isolate

    NARCIS (Netherlands)

    Butré, C.I.; Wierenga, P.A.; Gruppen, H.

    2012-01-01

    To identify the parameters that affect enzymatic hydrolysis at high substrate concentrations, whey protein isolate (1–30% w/v) was hydrolyzed by Alcalase and Neutrase at constant enzyme-to-substrate ratio. No changes were observed in the solubility and the aggregation state of the proteins. With

  16. Enzymatic hydrolysis of esters from 2-carboxy-6- methoxy-2,3 ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-11-02

    Nov 2, 2009 ... Full Length Research Paper. Enzymatic hydrolysis .... ml), followed by water (2 × 15 ml) and dried with anhydrous sodium .... dOptical purity of the acid was determined as the methyl ester by HPLC. eE values ..... Harada I, Hirose Y, Nakaozaki M (1968). ... Nicholas WR, Yang CG, Shi Z, He C (2006). Gold(I)- ...

  17. Eliminating inhibition of enzymatic hydrolysis by lignosulfonate in unwashed sulfite-pretreated aspen using metal salts

    Science.gov (United States)

    Hao Liu; Junyong Zhu

    2010-01-01

    This study demonstrated the efficiency of Ca(II) and Mg(II) in removing inhibition of enzymatic hydrolysis by lignosulfonate through non-productive adsorption of enzymes. Adding 1 mmol/g cellulose of either metal salt restores approximately 65% of the activity lost when a pure cellulose/cellulase solution is spiked with lignosulfonate. Addition of either Ca(II) or Mg(...

  18. Degradation of Collagen Increases Nitrogen Solubilisation During Enzymatic Hydrolysis of Fleshing Meat

    NARCIS (Netherlands)

    Anzani, Cecilia; Prandi, Barbara; Tedeschi, Tullia; Baldinelli, Chiara; Sorlini, Giovanni; Wierenga, Peter A.; Dossena, Arnaldo; Sforza, Stefano

    2017-01-01

    Abstract: The meat portion directly attached to bovine hides (fleshing meat) is a by-product of leather industry that is a potential new source of proteins. In literature different enzymatic and chemical methods have been proposed to hydrolyze and solubilize fleshing meat. Enzyme hydrolysis is

  19. Pretreatments and enzymatic hydrolysis of sugarcane bagasse aiming at the enhancement of the yield of glucose and xylose

    Directory of Open Access Journals (Sweden)

    A. de A. Guilherme

    Full Text Available ABSTRACT This work studied the enzymatic hydrolysis of sugarcane bagasse aiming at the production of glucose and xylose. The bagasse was subjected to two different pretreatments: combined acid and alkalinepretreatment and hydrogen peroxidepretreatment. The enzymatic hydrolysis was optimized and a kinetic study was carried out in a stirred tank reactor (STR in batch mode. Optimal conditions were obtained by subjecting the bagasse to the hydrogen peroxide pretreatment followed by enzymatic hydrolysis. The addition of xylanases to the enzymatic mixture improved the production of fermentable sugars by 48%.

  20. Effect of Enzymatic Hydrolysis on the Antioxidant Properties of Alcoholic Extracts of Oilseed Cakes

    Directory of Open Access Journals (Sweden)

    Jacek Arct

    2013-01-01

    Full Text Available The aim of the present study is to compare changes in the total phenolic, flavonoid and reducing sugar content and antioxidant activity of alcoholic extracts of Oenothera biennis, Borago officinalis and Nigella sativa oilseed cakes before and after enzymatic hydrolysis. Extraction with ethanol and hydrolysis with different commercially available glycosidases: α-amylase, β-glucosidase, β-glucanase and their combinations in a ratio of 1:1:1 were investigated. Total phenolic, flavonoid and reducing sugar content, iron-chelating activity and antioxidant activity according to DPPH and ABTS tests were measured in non-hydrolysed extracts and compared with the results obtained for the extracts after the application of immobilised enzymes. As a result, the hydrolysed extracts had a higher phenolic and reducing sugar content as well as higher iron-chelating and antioxidant activities. Total phenolic content of Oenothera biennis, Borago officinalis and Nigella sativa oilseed cake extracts after enzymatic hydrolysis was higher in comparison with non-hydrolysed extracts, i.e. 2 times (for the enzyme combination, and 1.5 and 2 times (for β-glucanase (p<0.05, respectively. The best results in increasing the flavonoid and sugar content as well as in iron-chelating activity were obtained after enzymatic hydrolysis of oilseed cake extracts by β-glucanase. Oilseed cake extracts after hydrolysis with an enzyme combination in a ratio of 1:1:1 had the highest increase in antioxidant activity.

  1. Enzymatic hydrolysis at high-solids loadings for the conversion of agave bagasse to fuel ethanol

    International Nuclear Information System (INIS)

    Caspeta, Luis; Caro-Bermúdez, Mario A.; Ponce-Noyola, Teresa; Martinez, Alfredo

    2014-01-01

    Highlights: • Conversion of agave bagasse to fuel ethanol. • Ethanosolv-pretreatment variables were statistically adjusted. • 91% of total sugars found in agave bagasse were recovered. • 225 g/L glucose from 30%-consistency hydrolysis using mini-reactors with peg-mixers. • 0.25 g of ethanol per g of dry agave bagasse was obtained. - Abstract: Agave bagasse is the lignocellulosic residue accumulated during the production of alcoholic beverages in Mexico and is a potential feedstock for the production of biofuels. A factorial design was used to investigate the effect of temperature, residence time and concentrations of acid and ethanol on ethanosolv pretreatment and enzymatic hydrolysis of agave bagasse. This method and the use of a stirred in-house-made mini-reactor increased the digestibility of agave bagasse from 30% observed with the dilute-acid method to 98%; also allowed reducing the quantity of enzymes used to hydrolyze samples with solid loadings of 30% w/w and glucose concentrations up to 225 g/L were obtained in the enzymatic hydrolysates. Overall this process allows the recovery of 91% of the total fermentable sugars contained in the agave bagasse (0.51 g/g) and 69% of total lignin as co-product (0.11 g/g). The maximum ethanol yield under optimal conditions using an industrial yeast strain for the fermentation was 0.25 g/g of dry agave bagasse, which is 86% of the maximum theoretical (0.29 g/g). The effect of the glucose concentration and solid loading on the conversion of cellulose to glucose is discussed, in addition to prospective production of about 50 million liters of fuel ethanol using agave bagasse residues from the tequila industry as a potential solution to the disposal problems

  2. Effect of metal ions on the enzymatic hydrolysis of hemp seed oil by lipase Candida sp. 99-125.

    Science.gov (United States)

    Lu, Jike; Wang, Pei; Ke, Zhaodi; Liu, Xin; Kang, Qiaozhen; Hao, Limin

    2018-07-15

    In order to study the effect of metal ions on the enzymatic hydrolysis of hemp seed oil by Candida sp. 99-125, the spectroscopy, stability and hydrolytic activity of the biocatalyst were investigated in presence of Ca 2+ , Mg 2+ , Fe 2+ , Fe 3+ , Cu 2+ , Sn 2+ , Pb 2+ , Zn 2+ and Ba 2+ metal ions, respectively. The UV spectroscopy showed that all the metal ions enhanced the absorbance but the decrease of fluorescence intensity was observed. All the metal ions could improve the lipase thermal stability except Cu 2+ and Ba 2+ . Hydrolysis of hemp seed oil proved that Ca 2+ , Fe 3+ , Pb 2+ and Ba 2+ could significantly improve the hydrolytic rate, and metal ions could influence lipase selectivity. The study revealed that metal ions could improve lipase stability, hydrolysis activity in the hydrolytic process of hemp seed oil by Candida sp. 99-125. Copyright © 2018 Elsevier B.V. All rights reserved.

  3. Fish protein hydrolysate production from sardine solid waste by crude pepsin enzymatic hydrolysis in a bioreactor coupled to an ultrafiltration unit

    International Nuclear Information System (INIS)

    Benhabiles, M.S.; Abdi, N.; Drouiche, N.; Lounici, H.; Pauss, A.; Goosen, M.F.A.; Mameri, N.

    2012-01-01

    The aims of the study were to optimize the production a fish protein hydrolysate (FPH) by enzymatic hydrolysis of sardine solid waste using crude pepsin, and to scale up the process in a bioreactor coupled to an ultrafiltration unit for product recovery. Results showed that the crude pepsin prepared by autolysis of the mucous membranes of a sheep stomach at optimal conditions (i. e. pH = 1.5–2 and incubation time of 6 h) could be satisfactory used for the enzymatic hydrolysis of fish solid waste. The optimal conditions for enzymatic reaction were: temperature 48 °C, and pH 1.5. The scale up of the enzymatic hydrolysis and the coupling of the reactor an ultrafiltration unit to concentrate the hydrolysate gave good results with a rejection coefficient for the protein hydrolysate product in the range of 90%. The volumetric concentration factor was 2.5, with a permeate flux of 200 L m −2 bar −1 . However, the results also suggest that the ultrafiltration product concentration process may be operating beyond the critical flux at which point irreversible membrane fouling occurs. - Highlights: ► Evaluating to produce a (FPH) by enzymatic hydrolysis of sardine solid wastes was achieved. ► Investigation of key parameters for optimal conditions for enzymatic hydrolysis have been studied. ► Valorization of sardine waste was realized by enzymatic hydrolysis process. ► Performances of this enzyme gave comparable results to those obtained with commercial pepsin. ► The nutritional quality of the FPH produced appears to be satisfactory.

  4. Fish protein hydrolysate production from sardine solid waste by crude pepsin enzymatic hydrolysis in a bioreactor coupled to an ultrafiltration unit

    Energy Technology Data Exchange (ETDEWEB)

    Benhabiles, M.S.; Abdi, N. [National Polytechnic school of Algiers, B.P. 182-16200, El Harrach, Algiers (Algeria); Drouiche, N., E-mail: nadjibdrouiche@yahoo.fr [National Polytechnic school of Algiers, B.P. 182-16200, El Harrach, Algiers (Algeria); Silicon Technology Development Unit (UDTS) 2, Bd Frantz Fanon BP140, Alger-7 Merveilles, 16000 (Algeria); Lounici, H. [National Polytechnic school of Algiers, B.P. 182-16200, El Harrach, Algiers (Algeria); Pauss, A. [University of Technology of Compiegne, Departement Genie chimique,B.P. 20.509, 60205 Compiegne cedex (France); Goosen, M.F.A. [Alfaisal University, Riyadh (Saudi Arabia); Mameri, N. [University of Technology of Compiegne, Departement Genie chimique,B.P. 20.509, 60205 Compiegne cedex (France)

    2012-05-01

    The aims of the study were to optimize the production a fish protein hydrolysate (FPH) by enzymatic hydrolysis of sardine solid waste using crude pepsin, and to scale up the process in a bioreactor coupled to an ultrafiltration unit for product recovery. Results showed that the crude pepsin prepared by autolysis of the mucous membranes of a sheep stomach at optimal conditions (i. e. pH = 1.5-2 and incubation time of 6 h) could be satisfactory used for the enzymatic hydrolysis of fish solid waste. The optimal conditions for enzymatic reaction were: temperature 48 Degree-Sign C, and pH 1.5. The scale up of the enzymatic hydrolysis and the coupling of the reactor an ultrafiltration unit to concentrate the hydrolysate gave good results with a rejection coefficient for the protein hydrolysate product in the range of 90%. The volumetric concentration factor was 2.5, with a permeate flux of 200 L m{sup -2} bar{sup -1}. However, the results also suggest that the ultrafiltration product concentration process may be operating beyond the critical flux at which point irreversible membrane fouling occurs. - Highlights: Black-Right-Pointing-Pointer Evaluating to produce a (FPH) by enzymatic hydrolysis of sardine solid wastes was achieved. Black-Right-Pointing-Pointer Investigation of key parameters for optimal conditions for enzymatic hydrolysis have been studied. Black-Right-Pointing-Pointer Valorization of sardine waste was realized by enzymatic hydrolysis process. Black-Right-Pointing-Pointer Performances of this enzyme gave comparable results to those obtained with commercial pepsin. Black-Right-Pointing-Pointer The nutritional quality of the FPH produced appears to be satisfactory.

  5. Effect of γ-rays radiation pretreatment on enzymatic hydrolysis of corn straw for producing sugar

    International Nuclear Information System (INIS)

    Tang Hongtao; Ha Yiming; Wang Feng

    2011-01-01

    The effect of γ-rays radiation pretreatment on enzymatic of corn straw for producing sugar was studied. The relationship between irradiation-dosage and content of reducing sugar was investigated in DNS method. After 1000 kGy irradiation, the content of reducing sugar reached about 317.35%. A synergistic effect between irradiation and enzyme was observed. The reducing sugar yield after enzymatic hydrolysis reached 20.51% when the corn straw powder (0.15 mm) irradiated with a dose of 1000 kGy. The result shows that the irradiation had significant influence on enzymatic hydrolysis of corn straw. At the 500 kGy pre-irradiation, compared with initial yield, the maximum sugar yield of sample had increased by 13.68% while the irradiated corn straw stored in 20 days. (authors)

  6. Barley grain constituents, starch composition, and structure affect starch in vitro enzymatic hydrolysis.

    Science.gov (United States)

    Asare, Eric K; Jaiswal, Sarita; Maley, Jason; Båga, Monica; Sammynaiken, Ramaswami; Rossnagel, Brian G; Chibbar, Ravindra N

    2011-05-11

    The relationship between starch physical properties and enzymatic hydrolysis was determined using ten different hulless barley genotypes with variable carbohydrate composition. The ten barley genotypes included one normal starch (CDC McGwire), three increased amylose starches (SH99250, SH99073, and SB94893), and six waxy starches (CDC Alamo, CDC Fibar, CDC Candle, Waxy Betzes, CDC Rattan, and SB94912). Total starch concentration positively influenced thousand grain weight (TGW) (r(2) = 0.70, p starch concentration (r(2) = -0.80, p hydrolysis of pure starch (r(2) = -0.67, p starch concentration (r(2) = 0.46, p starch (RS) in meal and pure starch samples. The rate of starch hydrolysis was high in pure starch samples as compared to meal samples. Enzymatic hydrolysis rate both in meal and pure starch samples followed the order waxy > normal > increased amylose. Rapidly digestible starch (RDS) increased with a decrease in amylose concentration. Atomic force microscopy (AFM) analysis revealed a higher polydispersity index of amylose in CDC McGwire and increased amylose genotypes which could contribute to their reduced enzymatic hydrolysis, compared to waxy starch genotypes. Increased β-glucan and dietary fiber concentration also reduced the enzymatic hydrolysis of meal samples. An average linkage cluster analysis dendrogram revealed that variation in amylose concentration significantly (p starch concentration in meal and pure starch samples. RS is also associated with B-type granules (5-15 μm) and the amylopectin F-III (19-36 DP) fraction. In conclusion, the results suggest that barley genotype SH99250 with less decrease in grain weight in comparison to that of other increased amylose genotypes (SH99073 and SH94893) could be a promising genotype to develop cultivars with increased amylose grain starch without compromising grain weight and yield.

  7. Kinetics of enzymatic high-solid hydrolysis of lignocellulosic biomass studied by calorimetry.

    Science.gov (United States)

    Olsen, Søren N; Lumby, Erik; McFarland, Kc; Borch, Kim; Westh, Peter

    2011-03-01

    Enzymatic hydrolysis of high-solid biomass (>10% w/w dry mass) has become increasingly important as a key step in the production of second-generation bioethanol. To this end, development of quantitative real-time assays is desirable both for empirical optimization and for detailed kinetic analysis. In the current work, we have investigated the application of isothermal calorimetry to study the kinetics of enzymatic hydrolysis of two substrates (pretreated corn stover and Avicel) at high-solid contents (up to 29% w/w). It was found that the calorimetric heat flow provided a true measure of the hydrolysis rate with a detection limit of about 500 pmol glucose s(-1). Hence, calorimetry is shown to be a highly sensitive real-time method, applicable for high solids, and independent on the complexity of the substrate. Dose-response experiments with a typical cellulase cocktail enabled a multidimensional analysis of the interrelationships of enzyme load and the rate, time, and extent of the reaction. The results suggest that the hydrolysis rate of pretreated corn stover is limited initially by available attack points on the substrate surface (conversion) but becomes proportional to enzyme dosage (excess of attack points) at later stages (>10% conversion). This kinetic profile is interpreted as an increase in polymer end concentration (substrate for CBH) as the hydrolysis progresses, probably due to EG activity in the enzyme cocktail. Finally, irreversible enzyme inactivation did not appear to be the source of reduced hydrolysis rate over time.

  8. High glucose recovery from direct enzymatic hydrolysis of bisulfite-pretreatment on non-detoxified furfural residues.

    Science.gov (United States)

    Xing, Yang; Bu, Lingxi; Sun, Dafeng; Liu, Zhiping; Liu, Shijie; Jiang, Jianxin

    2015-10-01

    This study reports four schemes to pretreat wet furfural residues (FRs) with sodium bisulfite for production of fermentable sugar. The results showed that non-detoxified FRs (pH 2-3) had great potential to lower the cost of bioconversion. The optimal process was that unwashed FRs were first pretreated with bisulfite, and the whole slurry was then directly used for enzymatic hydrolysis. A maximum glucose yield of 99.4% was achieved from substrates pretreated with 0.1 g NaHSO3/g dry substrate (DS), at a relatively low temperature of 100 °C for 3 h. Compared with raw material, enzymatic hydrolysis at a high-solid of 16.5% (w/w) specifically showed more excellent performance with bisulfite treated FRs. Direct bisulfite pretreatment improved the accessibility of substrates and the total glucose recovery. Lignosulfonate in the non-detoxified slurry decreased the non-productive adsorption of cellulase on the substrate, thus improving enzymatic hydrolysis. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Recovery of Whey Proteins and Enzymatic Hydrolysis of Lactose Derived from Casein Whey Using a Tangential Flow Ultrafiltration Module

    Science.gov (United States)

    Das, Bipasha; Bhattacharjee, Sangita; Bhattacharjee, Chiranjib

    2013-09-01

    In this study, ultrafiltration (UF) of pretreated casein whey was carried out in a cross-flow module fitted with 5 kDa molecular weight cut-off polyethersulfone membrane to recover whey proteins in the retentate and lactose in the permeate. Effects of processing conditions, like transmembrane pressure and pH on permeate flux and rejection were investigated and reported. The polarised layer resistance was found to increase with time during UF even in this high shear device. The lactose concentration in the permeate was measured using dinitro salicylic acid method. Enzymatic kinetic study for lactose hydrolysis was carried out at three different temperatures ranging from 30 to 50 °C using β-galactosidase enzyme. The glucose formed during lactose hydrolysis was analyzed using glucose oxidase-peroxidase method. Kinetics of enzymatic hydrolysis of lactose solution was found to follow Michaelis-Menten model and the model parameters were estimated by Lineweaver-Burk plot. The hydrolysis rate was found to be maximum (with Vmax = 5.5091 mmol/L/min) at 30 °C.

  10. Comparison of aqueous ammonia and dilute acid pretreatment of bamboo fractions: Structure properties and enzymatic hydrolysis.

    Science.gov (United States)

    Xin, Donglin; Yang, Zhong; Liu, Feng; Xu, Xueru; Zhang, Junhua

    2015-01-01

    The effect of two pretreatments methods, aqueous ammonia (SAA) and dilute acid (DA), on the chemical compositions, cellulose crystallinity, morphologic change, and enzymatic hydrolysis of bamboo fractions (bamboo yellow, timber, green, and knot) was compared. Bamboo fractions with SAA pretreatment had better hydrolysability than those with DA pretreatment. High crystallinity index resulted in low hydrolysis yield in the conversion of SAA pretreated bamboo fractions, not DA pretreated fractions. The increase of cellulase loading had modestly positive effect in the hydrolysis of both SAA and DA pretreated bamboo fractions, while supplement of xylanase significantly increased the hydrolysis of the pretreated bamboo fractions, especially after SAA pretreatment. The results indicated that SAA pretreatment was more effective than DA pretreatment in conversion of bamboo fractions, and supplementation of xylanase was necessary in effective conversion of the SAA pretreated fractions into fermentable sugars. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Defense waste processing facility precipitate hydrolysis process

    International Nuclear Information System (INIS)

    Doherty, J.P.; Eibling, R.E.; Marek, J.C.

    1986-03-01

    Sodium tetraphenylborate and sodium titanate are used to assist in the concentration of soluble radionuclide in the Savannah River Plant's high-level waste. In the Defense Waste Processing Facility, concentrated tetraphenylborate/sodium titanate slurry containing cesium-137, strontium-90 and traces of plutonium from the waste tank farm is hydrolyzed in the Salt Processing Cell forming organic and aqueous phases. The two phases are then separated and the organic phase is decontaminated for incineration outside the DWPF building. The aqueous phase, containing the radionuclides and less than 10% of the original organic, is blended with the insoluble radionuclides in the high-level waste sludge and is fed to the glass melter for vitrification into borosilicate glass. During the Savannah River Laboratory's development of this process, copper (II) was found to act as a catalyst during the hydrolysis reactions, which improved the organic removal and simplified the design of the reactor

  12. Process development of starch hydrolysis using mixing characteristics of Taylor vortices.

    Science.gov (United States)

    Masuda, Hayato; Horie, Takafumi; Hubacz, Robert; Ohmura, Naoto; Shimoyamada, Makoto

    2017-04-01

    In food industries, enzymatic starch hydrolysis is an important process that consists of two steps: gelatinization and saccharification. One of the major difficulties in designing the starch hydrolysis process is the sharp change in its rheological properties. In this study, Taylor-Couette flow reactor was applied to continuous starch hydrolysis process. The concentration of reducing sugar produced via enzymatic hydrolysis was evaluated by varying operational variables: rotational speed of the inner cylinder, axial velocity (reaction time), amount of enzyme, and initial starch content in the slurry. When Taylor vortices were formed in the annular space, efficient hydrolysis occurred because Taylor vortices improved the mixing of gelatinized starch with enzyme. Furthermore, a modified inner cylinder was proposed, and its mixing performance was numerically investigated. The modified inner cylinder showed higher potential for enhanced mixing of gelatinized starch and the enzyme than the conventional cylinder.

  13. Process for teating whey by enzymic hydrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Nocquet, J L

    1980-01-01

    In the process lactose is converted into glucose and galactose, with demineralization to a level of at least 50%, before the hydrolysis. A bacteriologically stable hydrolysed whey is obtained and may be used in foods for human consumption.

  14. Radiation pretreatments of cellulose materials for the enhancement of enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Ardica, S.; Calderaro, E.; Cappadona, C.

    1985-01-01

    The effect of γ-ray pre-irradiation of cellulose materials such as wood chips, paper, grain straw, hay and kapok on glucose production on enzymatic hydrolysis by cellulase has been investigated. These materials have been irradiated in air, water and acetate buffer solution over the dose range 10 3 to 4 x 10 6 Gy. In the relatively low dose range, up to about 5 x 10 5 Gy, the glucose yields after enzymatic hydrolysis are practically insensitive to radiation. At higher dose levels, up to 1.7 to 2 x 10 6 Gy, the pre-irradiation becomes very effective on enzymatic cellulose conversion. It has been found that the radiation-induced degradation of cellulose into low molecular weight polysaccharides is dependent on the nature and chemical composition of the cellulose materials and on the radiation environmental conditions. Further increases of dose causes radiation-induced structural modifications in polysaccharides previously produced, which can lead to a decrease in glucose production by enzymatic hydrolysis. (author)

  15. Enhancing bioactive peptide release and identification using targeted enzymatic hydrolysis of milk proteins.

    Science.gov (United States)

    Nongonierma, Alice B; FitzGerald, Richard J

    2018-06-01

    Milk proteins have been extensively studied for their ability to yield a range of bioactive peptides following enzymatic hydrolysis/digestion. However, many hurdles still exist regarding the widespread utilization of milk protein-derived bioactive peptides as health enhancing agents for humans. These mostly arise from the fact that most milk protein-derived bioactive peptides are not highly potent. In addition, they may be degraded during gastrointestinal digestion and/or have a low intestinal permeability. The targeted release of bioactive peptides during the enzymatic hydrolysis of milk proteins may allow the generation of particularly potent bioactive hydrolysates and peptides. Therefore, the development of milk protein hydrolysates capable of improving human health requires, in the first instance, optimized targeted release of specific bioactive peptides. The targeted hydrolysis of milk proteins has been aided by a range of in silico tools. These include peptide cutters and predictive modeling linking bioactivity to peptide structure [i.e., molecular docking, quantitative structure activity relationship (QSAR)], or hydrolysis parameters [design of experiments (DOE)]. Different targeted enzymatic release strategies employed during the generation of milk protein hydrolysates are reviewed herein and their limitations are outlined. In addition, specific examples are provided to demonstrate how in silico tools may help in the identification and discovery of potent milk protein-derived peptides. It is anticipated that the development of novel strategies employing a range of in silico tools may help in the generation of milk protein hydrolysates containing potent and bioavailable peptides, which in turn may be used to validate their health promoting effects in humans. Graphical abstract The targeted enzymatic hydrolysis of milk proteins may allow the generation of highly potent and bioavailable bioactive peptides.

  16. Pungent Components from Thioglucosides in Armoracia rusticana Grown in China, Obtained by Enzymatic Hydrolysis

    OpenAIRE

    Rong Li; Jimmy C. Yu; Zi-Tao Jiang

    2006-01-01

    The conditions of enzymatic hydrolysis of thioglucosides, which are the precursors of the pungent components in Armoracia rusticana grown in China, were studied. The effects of incubation time, temperature, pH and the addition of ascorbic acid on the hydrolysis of thioglucosides were determined. The optimum hydrolytic conditions for the pungent components from thioglucosides were time, 120 min; temperature, 65 oC; pH=4.0 and ascorbic acid, 2 mg/g. The mixture of pungent components in a pale-y...

  17. Enzymatic Processes in Marine Biotechnology.

    Science.gov (United States)

    Trincone, Antonio

    2017-03-25

    In previous review articles the attention of the biocatalytically oriented scientific community towards the marine environment as a source of biocatalysts focused on the habitat-related properties of marine enzymes. Updates have already appeared in the literature, including marine examples of oxidoreductases, hydrolases, transferases, isomerases, ligases, and lyases ready for food and pharmaceutical applications. Here a new approach for searching the literature and presenting a more refined analysis is adopted with respect to previous surveys, centering the attention on the enzymatic process rather than on a single novel activity. Fields of applications are easily individuated: (i) the biorefinery value-chain, where the provision of biomass is one of the most important aspects, with aquaculture as the prominent sector; (ii) the food industry, where the interest in the marine domain is similarly developed to deal with the enzymatic procedures adopted in food manipulation; (iii) the selective and easy extraction/modification of structurally complex marine molecules, where enzymatic treatments are a recognized tool to improve efficiency and selectivity; and (iv) marine biomarkers and derived applications (bioremediation) in pollution monitoring are also included in that these studies could be of high significance for the appreciation of marine bioprocesses.

  18. Enzymatic hydrolysis of steam-pretreated lignocellulosic materials with Trichoderma atroviride enzymes produced in-house

    Directory of Open Access Journals (Sweden)

    Macrelli Stefano

    2009-07-01

    Full Text Available Abstract Background Improvement of the process of cellulase production and development of more efficient lignocellulose-degrading enzymes are necessary in order to reduce the cost of enzymes required in the biomass-to-bioethanol process. Results Lignocellulolytic enzyme complexes were produced by the mutant Trichoderma atroviride TUB F-1663 on three different steam-pretreated lignocellulosic substrates, namely spruce, wheat straw and sugarcane bagasse. Filter paper activities of the enzymes produced on the three materials were very similar, while β-glucosidase and hemicellulase activities were more dependent on the nature of the substrate. Hydrolysis of the enzyme preparations investigated produced similar glucose yields. However, the enzymes produced in-house proved to degrade the xylan and the xylose oligomers less efficiently than a commercial mixture of cellulase and β-glucosidase. Furthermore, accumulation of xylose oligomers was observed when the TUB F-1663 supernatants were applied to xylan-containing substrates, probably due to the low β-xylosidase activity of the enzymes. The efficiency of the enzymes produced in-house was enhanced by supplementation with extra commercial β-glucosidase and β-xylosidase. When the hydrolytic capacities of various mixtures of a commercial cellulase and a T. atroviride supernatant produced in the lab were investigated at the same enzyme loading, the glucose yield appeared to be correlated with the β-glucosidase activity, while the xylose yield seemed to be correlated with the β-xylosidase level in the mixtures. Conclusion Enzyme supernatants produced by the mutant T. atroviride TUB F-1663 on various pretreated lignocellulosic substrates have good filter paper activity values combined with high levels of β-glucosidase activities, leading to cellulose conversion in the enzymatic hydrolysis that is as efficient as with a commercial cellulase mixture. On the other hand, in order to achieve good xylan

  19. Surfactant-assisted pretreatment and enzymatic hydrolysis of spent mushroom compost for the production of sugars.

    Science.gov (United States)

    Kapu, N U S; Manning, M; Hurley, T B; Voigt, J; Cosgrove, D J; Romaine, C P

    2012-06-01

    Spent mushroom compost (SMC), a byproduct of commercial mushroom cultivation, poses serious environmental problems that have hampered the growth of this important agro-industry. In an effort to develop new applications for SMC, we explored its use as a feedstock for bioethanol production. SMC constitutes approximately 30%w/w polysaccharides, 66% of which is glucan. Following dilute-acid pretreatment and enzymatic hydrolysis, both in the presence of PEG 6000, 97% of glucan and 44% of xylan in SMC were converted into the corresponding monosaccharides. Incorporation of PEG 6000 reduced the cellulase requirement by 77%. Zwittergent 3-12 and 3-14 also significantly increased the efficacy of acid pretreatment and enzymatic hydrolysis. The use of SMC in bioethanol production represents a potential mitigation solution for the critical environmental issues associated with the stockpiling of the major byproduct of the mushroom industry. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. Modification of chemical reactivity of enzymatic hydrolysis lignin by ultrasound treatment in dilute alkaline solutions.

    Science.gov (United States)

    Ma, Zhuoming; Li, Shujun; Fang, Guizhen; Patil, Nikhil; Yan, Ning

    2016-12-01

    In this study, we have explored various ultrasound treatment conditions for structural modification of enzymatic hydrolysis lignin (EHL) for enhanced chemical reactivity. The key structural modifications were characterized by using a combination of analytical methods, including, Fourier Transform-Infrared spectroscopy (FTIR), Proton Nuclear Magnetic Resonance ( 1 H NMR), Gel permeation chromatography (GPC), X-ray photoelectron spectroscopy (XPS), and Folin-Ciocalteu (F-C) method. Chemical reactivity of the modified EHL samples was determined by both 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity and their reactivity towards formaldehyde. It was observed that the modified EHL had a higher phenolic hydroxyl group content, a lower molecular weight, a higher reactivity towards formaldehyde, and a greater antioxidant property. The higher reactivity demonstrated by the samples after treatment suggesting that ultrasound is a promising method for modifying enzymatic hydrolysis lignin for value-added applications. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Kinetic study of enzymatic hydrolysis of acid-pretreated coconut coir

    Science.gov (United States)

    Fatmawati, Akbarningrum; Agustriyanto, Rudy

    2015-12-01

    Biomass waste utilization for biofuel production such as bioethanol, has become more prominent currently. Coconut coir is one of lignocellulosic food wastes, which is abundant in Indonesia. Bioethanol production from such materials consists of more than one step. Pretreatment and enzymatic hydrolysis is crucial steps to produce sugar which can then be fermented into bioethanol. In this research, ground coconut coir was pretreated using dilute sulfuric acid at 121°C. This pretreatment had increased the cellulose content and decreased the lignin content of coconut coir. The pretreated coconut coir was hydrolyzed using a mix of two commercial cellulase enzymes at pH of 4.8 and temperature of 50°C. The enzymatic hydrolysis was conducted at several initial coconut coir slurry concentrations (0.1-2 g/100 mL) and reaction times (2-72 hours). The reducing sugar concentration profiles had been produced and can be used to obtain reaction rates. The highest reducing sugar concentration obtained was 1,152.567 mg/L, which was produced at initial slurry concentration of 2 g/100 mL and 72 hours reaction time. In this paper, the reducing sugar concentrations were empirically modeled as a function of reaction time using power equations. Michaelis-Menten kinetic model for enzymatic hydrolysis reaction is adopted. The kinetic parameters of that model for sulfuric acid-pretreated coconut coir enzymatic hydrolysis had been obtained which are Vm of 3.587×104 mg/L.h, and KM of 130.6 mg/L.

  2. Biohydrogen production from enzymatic hydrolysis of food waste in batch and continuous systems

    OpenAIRE

    Wei Han; Yingting Yan; Yiwen Shi; Jingjing Gu; Junhong Tang; Hongting Zhao

    2016-01-01

    In this study, the feasibility of biohydrogen production from enzymatic hydrolysis of food waste was investigated. Food waste (solid-to-liquid ratio of 10%, w/v) was first hydrolyzed by commercial glucoamylase to release glucose (24.35?g/L) in the food waste hydrolysate. Then, the obtained food waste hydrolysate was used as substrate for biohydrogen production in the batch and continuous (continuous stirred tank reactor, CSTR) systems. It was observed that the maximum cumulative hydrogen prod...

  3. The dual effects of Maillard reaction and enzymatic hydrolysis on the antioxidant activity of milk proteins.

    Science.gov (United States)

    Oh, N S; Lee, H A; Lee, J Y; Joung, J Y; Lee, K B; Kim, Y; Lee, K W; Kim, S H

    2013-08-01

    The objective of this study was to determine the enhanced effects on the biological characteristics and antioxidant activity of milk proteins by the combination of the Maillard reaction and enzymatic hydrolysis. Maillard reaction products were obtained from milk protein preparations, such as whey protein concentrates and sodium caseinate with lactose, by heating at 55°C for 7 d in sodium phosphate buffer (pH 7.4). The Maillard reaction products, along with untreated milk proteins as controls, were hydrolyzed for 0 to 3h with commercial proteases Alcalase, Neutrase, Protamex, and Flavorzyme (Novozymes, Bagsværd, Denmark). The antioxidant activity of hydrolyzed Maillard reaction products was determined by reaction with 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, their 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, and the ability to reduce ferric ions. Further characteristics were evaluated by the o-phthaldialdehyde method and sodium dodecyl sulfate-PAGE. The degree of hydrolysis gradually increased in a time-dependent manner, with the Alcalase-treated Maillard reaction products being the most highly hydrolyzed. Radical scavenging activities and reducing ability of hydrolyzed Maillard reaction products increased with increasing hydrolysis time. The combined products of enzymatic hydrolysis and Maillard reaction showed significantly greater antioxidant activity than did hydrolysates or Maillard reaction products alone. The hydrolyzed Maillard reaction products generated by Alcalase showed significantly higher antioxidant activity when compared with the other protease products and the antioxidant activity was higher for the whey protein concentrate groups than for the sodium caseinate groups. These findings indicate that Maillard reaction products, coupled with enzymatic hydrolysis, could act as potential antioxidants in the pharmaceutical, food, and dairy industries. Copyright © 2013 American Dairy Science Association

  4. Effects of lipids on enzymatic hydrolysis and physical properties of starch.

    Science.gov (United States)

    Ai, Yongfeng; Hasjim, Jovin; Jane, Jay-lin

    2013-01-30

    This study aimed to understand effects of lipids, including corn oil (CO), soy lecithin (SL), palmitic acid (PA), stearic acid (SA), oleic acid (OA), and linoleic acid (LA), on the enzymatic hydrolysis and physical properties of normal corn (NCS), tapioca (TPS), waxy corn (WCS), and high-amylose corn (HA7) starch, and to elucidate mechanisms of interactions between the starches and lipids. After cooking with the lipids (10%, w/w, dsb), NCS, TPS, and HA7 showed significant decreases in enzymatic hydrolysis, and their DSC thermograms displayed amylose-lipid-complex dissociation peaks except with the CO. (13)C NMR spectra of amylodextrin with CO showed downfield changes in the chemical shifts of carbons 1 and 4 of the anhydroglucose unit, indicating helical complex formation. Generally, free fatty acids (FFAs) reduced, but SL increased the peak viscosities of starches. FFAs and SL decreased, but CO increased the gel strength of NCS. These lipids displayed little impacts on the enzymatic hydrolysis and physical properties of WCS because it lacked amylose. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Effect of the steam explosion pretreatment on enzymatic hydrolysis of eucalyptus wood and sweet sorghum baggages

    International Nuclear Information System (INIS)

    Negro, M. J.; Martinez, J. M.; Manero, J.; Saez, F.; Martin, C.

    1991-01-01

    The effect of steam explosion treatment on the enzymatic hydrolysis yield of two different lignocellulosic substrates is studied. Raw materials have been pretreated in a pilot plant designed to work in batch and equipped with a reactor vessel of 2 1 working volume where biomass was heated at the desired temperature and then exploded and recovered in a cyclone. Temperatures from 190 to 230 degree celsius and reaction times from 2 to 8 min. have been assayed. The efficiency of the steam explosion treatment has been evaluated on the composition of the lignocellulosic materials as well as on their enzymatic hydrolysis yield using a cellulolytic complex from T. reesel. Results show a high solubilization rate of hemicelluloses and variable losses of cellulose and lignin depending on the conditions tested. Enzymatic hydrolysis yields of both substrates experimented remarkable increments, corresponding the highest values obtained to 210 degree celsius; 2 min. and 21O degree celsius; 4 min. for sorghum bagasse and eucalyptus wood respectively. (Author) 13 refs

  6. Effect of the steam explosion pretreatment on enzymatic hydrolysis of eucalyptus wood and sweet sorghum bagasse

    International Nuclear Information System (INIS)

    Negro, M.J.; Martinez, J.M.; Manero, J.; Saez, F.; Martin, C.

    1990-01-01

    The effect of steam explosion treatment on the enzymatic hydrolysis yield of two different lignocellulosic substrates is studied. Raw materials have been pretreated in a pilot plant designed to work in batch and equiped with a reactor vessel of 2 1 working volume where biomass was heated at the desired temperature and then exploded and recovered in a cyclone. Temperatures from 190 to 230 o C and reaction times from 2 to 8 min. have been assayed. The efficiency of the steam explosion treatment has been evaluated on the composition of the lignocellulosic materials as well as on their enzymatic hydrolysis yield using a cellulolytic complex from T. reesei. Results show a high solubilization rate of hemicelluloses ands variable losses of cellulose and lignin depending on the conditions tested. Enzymatic hydrolysis yields of both substrates experimented remarkable increments, correspondig the highest values obtained to 210 o C; 2 min. and 210 o C; 4 min. for sorghum bagasse and eucaliptus wood respectivelly. (Author). 13 refs

  7. Effect of lignin chemistry on the enzymatic hydrolysis of woody biomass.

    Science.gov (United States)

    Yu, Zhiying; Gwak, Ki-Seob; Treasure, Trevor; Jameel, Hasan; Chang, Hou-min; Park, Sunkyu

    2014-07-01

    The impact of lignin-derived inhibition on enzymatic hydrolysis is investigated by using lignins isolated from untreated woods and pretreated wood pulps. A new method, biomass reconstruction, for which isolated lignins are precipitated onto bleached pulps to mimic lignocellulosic biomass, is introduced, for the first time, to decouple the lignin distribution issue from lignin chemistry. Isolated lignins are physically mixed and reconstructed with bleached pulps. Lignins obtained from pretreated woods adsorb two to six times more cellulase than lignins obtained from untreated woods. The higher adsorption of enzymes on lignin correlates with decreased carbohydrate conversion in enzymatic hydrolysis. In addition, the reconstructed softwood substrate has a lower carbohydrate conversion than the reconstructed hardwood substrate. The degree of condensation of lignin increases significantly after pretreatment, especially with softwood lignins. In this study, the degree of condensation of lignin (0.02 to 0.64) and total OH groups in lignin (1.7 to 1.1) have a critical impact on cellulase adsorption (9 to 70%) and enzymatic hydrolysis (83.2 to 58.2%); this may provide insights into the more recalcitrant nature of softwood substrates. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Biological Pretreatment of Rubberwood with Ceriporiopsis subvermispora for Enzymatic Hydrolysis and Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Forough Nazarpour

    2013-01-01

    Full Text Available Rubberwood (Hevea brasiliensis, a potential raw material for bioethanol production due to its high cellulose content, was used as a novel feedstock for enzymatic hydrolysis and bioethanol production using biological pretreatment. To improve ethanol production, rubberwood was pretreated with white rot fungus Ceriporiopsis subvermispora to increase fermentation efficiency. The effects of particle size of rubberwood (1 mm, 0.5 mm, and 0.25 mm and pretreatment time on the biological pretreatment were first determined by chemical analysis and X-ray diffraction and their best condition obtained with 1 mm particle size and 90 days pretreatment. Further morphological study on rubberwood with 1 mm particle size pretreated by fungus was performed by FT-IR spectra analysis and SEM observation and the result indicated the ability of this fungus for pretreatment. A study on enzymatic hydrolysis resulted in an increased sugar yield of 27.67% as compared with untreated rubberwood (2.88%. The maximum ethanol concentration and yield were 17.9 g/L and 53% yield, respectively, after 120 hours. The results obtained demonstrate that rubberwood pretreated by C. subvermispora can be used as an alternative material for the enzymatic hydrolysis and bioethanol production.

  9. Benefits from additives and xylanase during enzymatic hydrolysis of bamboo shoot and mature bamboo.

    Science.gov (United States)

    Li, Kena; Wang, Xiao; Wang, Jingfeng; Zhang, Junhua

    2015-09-01

    Effects of additives (BSA, PEG 6000, and Tween 80) on enzymatic hydrolysis of bamboo shoot and mature bamboo fractions (bamboo green, bamboo timber, bamboo yellow, bamboo node, and bamboo branches) by cellulases and/or xylanase were evaluated. The addition of additives was comparable to the increase of cellulase loadings in the conversion of cellulose and xylan in bamboo fractions. Supplementation of xylanase (1 mg/g DM) with cellulases (10 FPU/g DM) in the hydrolysis of bamboo fractions was more efficient than addition of additives in the production of glucose and xylose. Moreover, addition of additives could further increase the glucose release from different bamboo fractions by cellulases and xylanase. Bamboo green exhibited the lowest hydrolyzability. Almost all of the polysaccharides in pretreated bamboo shoot fractions were hydrolyzed by cellulases with the addition of additives or xylanase. Additives and xylanase showed great potential for reducing cellulase requirement in the hydrolysis of bamboo. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The effect of nonenzymatic protein on lignocellulose enzymatic hydrolysis and simultaneous saccharification and fermentation.

    Science.gov (United States)

    Wang, Hui; Kobayashi, Shinichi; Hiraide, Hatsue; Cui, Zongjun; Mochidzuki, Kazuhiro

    2015-01-01

    Nonenzymatic protein was added to cellulase hydrolysis and simultaneous saccharification and fermentation (SSF) of different biomass materials. Adding bovine serum albumin (BSA) and corn steep before cellulase enhanced enzyme activity in solution and increased cellulose and xylose conversion rates. The cellulose conversion rate of filter paper hydrolysis was increased by 32.5 % with BSA treatment. When BSA was added before cellulase, the remaining activity in the solution was higher than that in a control without BSA pretreatment. During SSF with pretreated rice straw as the substrate, adding 1.0 mg/mL BSA increased the ethanol yield by 13.6 % and final xylose yield by 42.6 %. The results indicated that lignin interaction is not the only mechanism responsible for the positive BSA effect. BSA had a stabilizing effect on cellulase and relieved cumulative sugar inhibition of enzymatic hydrolysis of biomass materials. Thus, nonenzymatic protein addition represents a promising strategy in the biorefining of lignocellulose materials.

  11. Enhancing enzymatic hydrolysis of coconut husk through Pseudomonas aeruginosa AP 029/GLVIIA rhamnolipid preparation.

    Science.gov (United States)

    de Araújo, Cynthia Kérzia Costa; de Oliveira Campos, Alan; de Araújo Padilha, Carlos Eduardo; de Sousa Júnior, Francisco Canindé; do Nascimento, Ruthinéia Jéssica Alves; de Macedo, Gorete Ribeiro; Dos Santos, Everaldo Silvino

    2017-08-01

    This work investigated the influence of chemical (Triton X-100) and biological surfactant preparation (rhamnolipids) in coconut husk hydrolysis that was subjected to pretreatment with acid-alkali or alkaline hydrogen peroxide. The natural and pretreated biomass was characterized using the National Renewable Energy Laboratory protocol analysis as well as X-ray diffraction and scanning electron microscopy. The results demonstrated that in terms of the total reducing sugars, there was no significant difference between the hydrolysis using Triton X-100 and rhamnolipids, regardless of the pretreatment. A cellulosic conversion value as high as 33.0% was obtained in experiments with rhamnolipids. The coconut husk was observed to be a potential biomass that could produce second generation ethanol, and the rhamnolipid preparation can be used to support for the enzymatic hydrolysis, enhancing the advantage of cellulose conversion into glucose over chemical surfactants because it is an environmentally friendly approach. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Pretreatment of dried distillers grains with solubles by soaking in aqueous ammonia and subsequent enzymatic/dilute acid hydrolysis to produce fermentable sugars

    Science.gov (United States)

    Dried distillers grains with solubles (DDGS), a co-product of corn ethanol production in the dry-grind process, was pretreated by soaking in aqueous ammonia (SAA) using a 15% w/w NH4OH solution at a solid:liquid ratio of 1:10. The effect of pretreatment on subsequent enzymatic hydrolysis was studied...

  13. Behaviors and mechanism of acid dyes sorption onto diethylenetriamine-modified native and enzymatic hydrolysis starch

    International Nuclear Information System (INIS)

    Wang Zuohua; Xiang Bo; Cheng Rumei; Li Yijiu

    2010-01-01

    In this paper, different starches were modified by diethylenetriamine. The native starch reacted with diethylenetriamine giving CAS, whereas the enzymatic hydrolysis starch was modified by diethylenetriamine producing CAES. Adsorption capacities of CAES for four acid dyes, namely, Acid orange 7 (AO7), Acid orange 10 (AO10), Acid green 25 (AG25) and Acid red 18 (AR18) have been determined to be 2.521, 1.242, 1.798 and 1.570 mmol g -1 , respectively. In all cases, CAES has exhibited higher sorption ability than CAS, and the increment for these dyes took the sequence of AO7 (0.944 mmol g -1 ) > AO10 (0.592 mmol g -1 ) > AR18 (0.411 mmol g -1 ) > AG25 (0.047 mmol g -1 ). Sorption kinetics and isotherms analysis showed that these sorption processes were better fitted to pseudo-second-order equation and Langmuir equation. Chemical sorption mechanisms were confirmed by studying the effects of pH, ionic strength and hydrogen bonding. Thermodynamic parameters of these dyes onto CAES and CAS were also observed and it indicated that these sorption processes were exothermic and spontaneous in nature.

  14. Pretreated of banana pseudo-stem as raw material for enzymatic hydrolysis and bioethanol production

    Directory of Open Access Journals (Sweden)

    Kusmiyati

    2018-01-01

    Full Text Available Development of alternative energy is needed to solve the energy problem, including bioethanol. Banana pseudo-stem is a lignocellulose material that can used to produce bioethanol. Banana pseudo-stem has 28.83% cellulose and 19.39% lignin. The amount of lignin will reduce by pretreatment process. Variations of pretreatment methods by autoclaving of banana-pseudo stem in a steam, 0.5N, 1N, 1.5N, 2N NaOH solutions for 90 minutes were employed. Then the preteated samples were further enzymatic hydrolysed for 24, 48, 72 hours. The fermentation method of simultaneous saccharification and fermentation (SSF was applied using cellulase enzyme and yeast of Saccharomyces cerevisiae for 120 hours. The variation of the pretreatment process by increasing of NaOH concentration solutions led to decreased the lignin content while increased in cellulose content. The lowest lignin content was 11.44% and the highest cellulose was 51.66%. The highest sugar content was 29.8 g/L (at pretreatment 2N NaOH solution, 72 hours hydrolysis. The highest bioethanol amount (4.32 g/L was produced from pretreated banana stem using 2N NaOH solution.

  15. Effect of alkali lignins with different molecular weights from alkali pretreated rice straw hydrolyzate on enzymatic hydrolysis.

    Science.gov (United States)

    Li, Yun; Qi, Benkun; Luo, Jianquan; Wan, Yinhua

    2016-01-01

    This study investigated the effect of alkali lignins with different molecular weights on enzymatic hydrolysis of lignocellulose. Different alkali lignins fractions, which were obtained from cascade ultrafiltration, were added into the dilute acid pretreated (DAP) and alkali pretreated (AP) rice straws respectively during enzymatic hydrolysis. The results showed that the addition of alkali lignins enhanced the hydrolysis and the enhancement for hydrolysis increased with increasing molecular weights of alkali lignins, with maximum enhancement being 28.69% for DAP and 20.05% for AP, respectively. The enhancement was partly attributed to the improved cellulase activity, and filter paper activity increased by 18.03% when adding lignin with highest molecular weight. It was found that the enhancement of enzymatic hydrolysis was correlated with the adsorption affinity of cellulase on alkali lignins, and the difference in surface charge and hydrophobicity of alkali lignins were responsible for the difference in affinity between cellulase and lignins. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Electron beam application as pre treatment of sugar cane bagasse to enzymatic hydrolysis of cellulose

    International Nuclear Information System (INIS)

    Cardoso, Vanessa Miguel

    2008-01-01

    Due to increasing worldwide shortage of food and energy sources, sugarcane bagasse has been considered as a substrate for single cell protein, animal feed, and renewable energy production. Sugarcane bagasse generally contain up to 45% glucose polymer cellulose, much of which is in a crystalline structure, 40% hemicelluloses, an amorphous polymer usually composed of xylose, arabinose, galactose, glucose, and mannose and 20% lignin, which cannot be easily separated into readily usable components due to their recalcitrant nature. Pure cellulose is readily depolymerised by radiation, but in biomass the cellulose is intimately bonded with lignin, that protect it from radiation effects. The objective of this study was the evaluation of the electron beam irradiation efficiency as a pre-treatment to enzymatic hydrolysis of cellulose in order to facilitate its fermentation and improves the production of ethanol biofuel. Samples of sugarcane bagasse were obtained in sugar/ethanol Mill sited in Piracicaba, Brazil, and were irradiated using Radiation Dynamics Electron Beam Accelerator with 1,5 MeV energy and 37 kW, in batch systems. The applied absorbed doses of the fist sampling, Bagasse A, were 20 kGy, 50 kGy, 10 0 kGy and 200 kGy. After the evaluation the preliminary obtained results, it was applied lower absorbed doses in the second assay: 5 kGy, 10 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 100 kGy and 150 kGy. The electron beam processing took to changes in the sugarcane bagasse structure and composition, lignin and cellulose cleavage. The yield of enzymatic hydrolyzes of cellulose in. (author)

  17. Seafood-like flavour obtained from the enzymatic hydrolysis of the protein by-products of seaweed (Gracilaria sp.).

    Science.gov (United States)

    Laohakunjit, Natta; Selamassakul, Orrapun; Kerdchoechuen, Orapin

    2014-09-01

    An enzymatic bromelain seaweed protein hydrolysate (eb-SWPH) was characterised as the precursor for thermally processed seafood flavour. Seaweed (Gracilaria fisheri) protein after agar extraction was hydrolysed using bromelain (enzyme activity=119,325 U/g) at 0-20% (w/w) for 0.5-24 h. Optimal hydrolysis conditions were determined using response surface methodology. The proposed model took into account the interaction effect of the enzyme concentration and hydrolysis time on the physicochemical properties and volatile components of eb-SWPH. The optimal hydrolysis conditions for the production of eb-SWPH were 10% bromelain for 3h, which resulted in a 38.15% yield and a 62.91% degree of hydrolysis value. Three free amino acids, arginine, lysine, and leucine, were abundant in the best hydrolysate. Ten volatile flavours of the best eb-SWPH were identified using gas chromatography/mass spectrometry. The predominant odourants were hexanal, hexanoic acid, nonanoic acid, and dihydroactinidiolide. The thermally processed seafood flavour produced from eb-SWPH exhibited a roasted seafood-like flavouring. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. The enzymatic hydrolysis of lipids in a hydrophilic membrane bioreactor

    NARCIS (Netherlands)

    Pronk, W.

    1991-01-01

    The production of fatty acids from lipids (fats and oils) currently takes place in a physical chemical process at a high temperature and pressure. Fatty acids are applied in numerous products such as soaps, detergents and chemicals for pharmaceutical, household and industrial applications.

  19. Enzymatic lignocellulose hydrolysis: Improved cellulase productivity by insoluble solids recycling

    DEFF Research Database (Denmark)

    Weiss, Noah Daniel; Börjesson, Johan; Pedersen, Lars Saaby

    2013-01-01

    To take advantage of this effect, the amount of solids recycled should be maximized, based on a given processes ability to deal with higher solids concentrations and volumes. Recycling of enzymes by recycling the insoluble solids fraction was thus shown to be an effective method to decrease enzym...

  20. Alternatives for clarifying glucose syrup obtained by enzymatic hydrolysis of starch

    Directory of Open Access Journals (Sweden)

    Gloria Teresa Cruz Guerrero

    2004-05-01

    Full Text Available The present paper studies some routes for separating and purifying glucose syrup obtained by enzymatic hydrolysis of potato starch. The clarifying process is done in three stages. The first one (solids remotion is done by applying conventional solid-liquid separation techniiques such as sedimentation, centrifugation and filtration, as well as studying the effect of using flocculant and coagulant agents, prior to the already mentioned operations. Purification is done by adding decolouring agents, followed by ultrafiltration of the syrup. The last step (concentration is done by vacuum evaporation. The results showed that separation, centrifuging and sedimation reached 50% yield whilst filtration and ultrafiltration achieved 78% and 98% respectively. It was found that adsorbent agents such as activated carbon and diatomaceous earth were effective in removing colour during the purification stage. The most suitable alternative for separation can be suggested from the foregoing, allowing a syrup to be obtained having similar characteristics and propierties to the commercial product. The most appropriate technological module for carrying out the operation is also represented.

  1. A novel optimization approach to estimating kinetic parameters of the enzymatic hydrolysis of corn stover

    Directory of Open Access Journals (Sweden)

    Fenglei Qi

    2016-01-01

    Full Text Available Enzymatic hydrolysis is an integral step in the conversion of lignocellulosic biomass to ethanol. The conversion of cellulose to fermentable sugars in the presence of inhibitors is a complex kinetic problem. In this study, we describe a novel approach to estimating the kinetic parameters underlying this process. This study employs experimental data measuring substrate and enzyme loadings, sugar and acid inhibitions for the production of glucose. Multiple objectives to minimize the difference between model predictions and experimental observations are developed and optimized by adopting multi-objective particle swarm optimization method. Model reliability is assessed by exploring likelihood profile in each parameter space. Compared to previous studies, this approach improved the prediction of sugar yields by reducing the mean squared errors by 34% for glucose and 2.7% for cellobiose, suggesting improved agreement between model predictions and the experimental data. Furthermore, kinetic parameters such as K2IG2, K1IG, K2IG, K1IA, and K3IA are identified as contributors to the model non-identifiability and wide parameter confidence intervals. Model reliability analysis indicates possible ways to reduce model non-identifiability and tighten parameter confidence intervals. These results could help improve the design of lignocellulosic biorefineries by providing higher fidelity predictions of fermentable sugars under inhibitory conditions.

  2. A coupled CFD and two-phase substrate kinetic model for enzymatic hydrolysis of lignocellulose

    Science.gov (United States)

    Danes, Nicholas; Sitaraman, Hariswaran; Stickel, Jonathan; Sprague, Michael

    2017-11-01

    Cost-effective production of fuels from lignocellulosic biomass is an important subject of research in order to meet the world's current and future energy demands. Enzymatic hydrolysis is one of the several steps in the biochemical conversion of biomass into fuels. This process involves the interplay of non-Newtonian fluid dynamics that happen over tens of seconds coupled with chemical reactions that happen over several hours. In this work, we present a coupled CFD-reaction model for conversion of cellulose to sugars in a benchtop mixer reactor. A subcycling approach is used to circumvent the large time scale disparity between fluid dynamics and reactions. We will present a validation study of our simulations with experiments for well-mixed and stratified reactor scenarios along with predictions for conversion rates and product concentrations at varying impeller speeds and in scaled-up reactors. This work is funded by the Bioenergy Technology Office of DOE and the NSF's Enriched Doctoral Training program (DMS-1551229).

  3. Production and characterization of cowpea protein hydrolysate with optimum nitrogen solubility by enzymatic hydrolysis using pepsin.

    Science.gov (United States)

    Mune Mune, Martin Alain; Minka, Samuel René

    2017-06-01

    Cowpea is a source of low-cost and good nutritional quality protein for utilization in food formulations in replacement of animal proteins. Therefore it is necessary that cowpea protein exhibits good functionality, particularly protein solubility which affects the other functional properties. The objective of this study was to produce cowpea protein hydrolysate exhibiting optimum solubility by the adequate combination of hydrolysis parameters, namely time, solid/liquid ratio (SLR) and enzyme/substrate ratio (ESR), and to determine its functional properties and molecular characteristics. A Box-Behnken experimental design was used for the experiments, and a second-order polynomial to model the effects of hydrolysis time, SLR and ESR on the degree of hydrolysis and nitrogen solubility index. The optimum hydrolysis conditions of time 208.61 min, SLR 1/15 (w/w) and ESR 2.25% (w/w) yielded a nitrogen solubility of 75.71%. Protein breakdown and the peptide profile following enzymatic hydrolysis were evaluated by sodium dodecyl sulfate polyacrylamide gel electrophoresis and size exclusion chromatography. Cowpea protein hydrolysate showed higher oil absorption capacity, emulsifying activity and foaming ability compared with the concentrate. The solubility of cowpea protein hydrolysate was adequately optimized by response surface methodology, and the hydrolysate showed adequate functionality for use in food. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  4. Antioxidative activities of hydrolysates from edible birds nest using enzymatic hydrolysis

    Science.gov (United States)

    Muhammad, Nurul Nadia; Babji, Abdul Salam; Ayub, Mohd Khan

    2015-09-01

    Edible bird's nest protein hydrolysates (EBN) were prepared via enzymatic hydrolysis to investigate its antioxidant activity. Two types of enzyme (alcalase and papain) were used in this study and EBN had been hydrolysed with different hydrolysis time (30, 60, 90 and 120 min). Antioxidant activities in EBN protein hydrolysate were measured using DPPH, ABTS+ and Reducing Power Assay. From this study, increased hydrolysis time from 30 min to 120 min contributed to higher DH, as shown by alcalase (40.59%) and papain (24.94%). For antioxidant assay, EBN hydrolysed with papain showed higher scavenging activity and reducing power ability compared to alcalase. The highest antioxidant activity for papain was at 120 min hydrolysis time with ABTS (54.245%), DPPH (49.78%) and Reducing Power (0.0680). Meanwhile for alcalase, the highest antioxidant activity was at 30 min hydrolysis time. Even though scavenging activity for EBN protein hydrolysates were high, the reducing power ability was quite low as compared to BHT and ascorbic Acid. This study showed that EBN protein hydrolysate with alcalase and papain treatments potentially exhibit high antioxidant activity which have not been reported before.

  5. Research and determination of process parameters of milk lactose hydrolysis

    OpenAIRE

    Калинина, Елена Дмитриевна; Коваленко, Александр Владимирович

    2014-01-01

    The researches of enzymatic milk lactose hydrolysis by using the β - galactosidase enzyme are given in the paper. For carrying out a lactose hydrolysis, two β-galactosidase enzyme preparations GODO-YNL2 and Neolactase are offered. For setting lactose hydrolysis parameters, the influence of a pH medium, temperature, enzyme preparation doses, the duration of hydrolyzing the milk lactose affected by the β- galactosidase enzyme preparations, was studied. In terms of effectiveness, adaptability an...

  6. Combined enzymatic hydrolysis and fermentation of aspenwood using enzymes derived from Trichoderma harzianum E58

    Energy Technology Data Exchange (ETDEWEB)

    1989-05-01

    A project was initiated to study the conversion of aspenwood to ethanol, butanol or butanediol. The conversion method consisted of steam explosion pretreatment, followed by the enzymatic hydrolysis of the carbohydrate polymers, cellulose and hemicellulose. The enzyme was derived from a wild strain of the fungus Trichoderma harzianum E58, chosen because it produces a cellulose system that can degrade crystalline cellulose to glucose. The aspenwood was steamed at 240{degree}C for 80 seconds and then water and alkali extracted. The insoluble residue was 84% cellulose and was used for both enzyme production and the production of glucose, which was fermented to ethanol. Before fermentation of the water-soluble fraction was possible, the acetylxylan had to be hydrolyzed and the inhibitors (glucose, galactose, acetic and uronic acids, and lignin- and sugar-degradation products) removed. Enzymatic hydrolysis was found to generate less fermentation inhibitors than sulfuric acid hydrolysis. Due to market factors, fermentation research centred on the production of ethanol from hemicellulose, using the yeast Pichia stipitis. Although lignin had no effect on hydrolysis, it increased the bulk to be handled, in combination with small amounts of cellulose was found to strongly adsorb the cellulose enzymes, and broke down to produce inhibitors of the cellulose complex of T. harzanium and the enzyme production phase. Thus, it was advantageous to remove the lignin prior to enzyme production and cellular hydrolysis. None of the strategies were successful in decreasing the amount of cellulose required for enzyme production. It was concluded that T. harzianum E58 is unsuitable for use in a commercial bioconversion project. 59 refs., 31 figs., 31 tabs.

  7. Comparison and Optimization of Saccharification Conditions of Alkaline Pre-Treated Triticale Straw for Acid and Enzymatic Hydrolysis Followed by Ethanol Fermentation

    Directory of Open Access Journals (Sweden)

    Rafał Łukajtis

    2018-03-01

    Full Text Available This paper concerns the comparison of the efficiency of two-stage hydrolysis processes, i.e., alkaline pre-treatment and acid hydrolysis, as well as alkaline pre-treatment followed by enzymatic hydrolysis, carried out in order to obtain reducing sugars from triticale straw. For each of the analyzed systems, the optimization of the processing conditions was carried out with respect to the glucose yield. For the alkaline pre-treatment, an optimal catalyst concentration was selected for constant values of temperature and pre-treatment time. For enzymatic hydrolysis, optimal process time and concentration of the enzyme preparation were determined. For the acidic hydrolysis, performed with 85% phosphoric acid, the optimum temperature and hydrolysis time were determined. In the hydrolysates obtained after the two-stage treatment, the concentration of reducing sugars was determined using HPLC. The obtained hydrolysates were subjected to ethanol fermentation. The concentrations of fermentation inhibitors are given and their effects on the alcoholic fermentation efficiency are discussed.

  8. Biohydrogen production from enzymatic hydrolysis of food waste in batch and continuous systems

    Science.gov (United States)

    Han, Wei; Yan, Yingting; Shi, Yiwen; Gu, Jingjing; Tang, Junhong; Zhao, Hongting

    2016-01-01

    In this study, the feasibility of biohydrogen production from enzymatic hydrolysis of food waste was investigated. Food waste (solid-to-liquid ratio of 10%, w/v) was first hydrolyzed by commercial glucoamylase to release glucose (24.35 g/L) in the food waste hydrolysate. Then, the obtained food waste hydrolysate was used as substrate for biohydrogen production in the batch and continuous (continuous stirred tank reactor, CSTR) systems. It was observed that the maximum cumulative hydrogen production of 5850 mL was achieved with a yield of 245.7 mL hydrogen/g glucose (1.97 mol hydrogen/mol glucose) in the batch system. In the continuous system, the effect of hydraulic retention time (HRT) on biohydrogen production from food waste hydrolysate was investigated. The optimal HRT obtained from this study was 6 h with the highest hydrogen production rate of 8.02 mmol/(h·L). Ethanol and acetate were the major soluble microbial products with low propionate production at all HRTs. Enzymatic hydrolysis of food waste could effectively accelerate hydrolysis speed, improve substrate utilization rate and increase hydrogen yield. PMID:27910937

  9. Enzymatic hydrolysis of alkali-pretreated rice straw by Trichoderma reesei ZM4-F3

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, QiuZhuo [Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090 (China); Cai, WeiMin [Department of Environmental Science and Engineering, Harbin Institute of Technology, Harbin 150090 (China); School of Environmental Science and Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Minhang District, Shanghai 200240 (China)

    2008-12-15

    To minimize the cost of cellulase production, both pretreatment of the rice straw and on-site enzyme production were realized. Rice straw was first pretreated by 2% NaOH, which could increase cellulose by 54.83%, and decreased hemicellulose by 61.07% and lignin by 36.24%, respectively. Detected by SEM, significant morphological changes were observed in the tissue. Through orthogonal experiments, temperature 35 C, initial pH value 4.5 and the rotation speed of shaking bed 180 rpm were determined to be the optimal conditions for hydrolysis of rice straw by Trichoderma reesei ZM4-F3. After hydrolysis for 96 h, the production of FPA and reducing sugars could achieve 2.231 g l{sup -1} and 12.92 U ml{sup -1}, respectively. Moreover, T. reesei ZM4-F3 can decompose 68.21% of pretreated rice straw after 120 h of hydrolysis. By GC analysis, it showed that glucose is the main component of the enzymatic hydrolysates, which made GC seem to be more effective than the DNS method for analysis of the enzymatic hydrolysates as it can detect the concentration of each kind of monosaccharide more accurately. (author)

  10. Particle size distribution of rice flour affecting the starch enzymatic hydrolysis and hydration properties.

    Science.gov (United States)

    de la Hera, Esther; Gomez, Manuel; Rosell, Cristina M

    2013-10-15

    Rice flour is becoming very attractive as raw material, but there is lack of information about the influence of particle size on its functional properties and starch digestibility. This study evaluates the degree of dependence of the rice flour functional properties, mainly derived from starch behavior, with the particle size distribution. Hydration properties of flours and gels and starch enzymatic hydrolysis of individual fractions were assessed. Particle size heterogeneity on rice flour significantly affected functional properties and starch features, at room temperature and also after gelatinization; and the extent of that effect was grain type dependent. Particle size heterogeneity on rice flour induces different pattern in starch enzymatic hydrolysis, with the long grain having slower hydrolysis as indicated the rate constant (k). No correlation between starch digestibility and hydration properties or the protein content was observed. It seems that in intact granules interactions with other grain components must be taken into account. Overall, particle size fractionation of rice flour might be advisable for selecting specific physico-chemical properties. Copyright © 2013. Published by Elsevier Ltd.

  11. Optimization of enzymatic hydrolysis and fermentation conditions for improved bioethanol production from potato peel residues.

    Science.gov (United States)

    Ben Taher, Imen; Fickers, Patrick; Chniti, Sofien; Hassouna, Mnasser

    2017-03-01

    The aim of this work was the optimization of the enzyme hydrolysis of potato peel residues (PPR) for bioethanol production. The process included a pretreatment step followed by an enzyme hydrolysis using crude enzyme system composed of cellulase, amylase and hemicellulase, produced by a mixed culture of Aspergillus niger and Trichoderma reesei. Hydrothermal, alkali and acid pretreatments were considered with regards to the enhancement of enzyme hydrolysis of potato peel residues. The obtained results showed that hydrothermal pretreatment lead to a higher enzyme hydrolysis yield compared to both acid and alkali pretreatments. Enzyme hydrolysis was also optimized for parameters such as temperature, pH, substrate loading and surfactant loading using a response surface methodology. Under optimized conditions, 77 g L -1 of reducing sugars were obtained. Yeast fermentation of the released reducing sugars led to an ethanol titer of 30 g L -1 after supplementation of the culture medium with ammonium sulfate. Moreover, a comparative study between acid and enzyme hydrolysis of potato peel residues was investigated. Results showed that enzyme hydrolysis offers higher yield of bioethanol production than acid hydrolysis. These results highlight the potential of second generation bioethanol production from potato peel residues treated with onsite produced hydrolytic enzymes. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 33:397-406, 2017. © 2017 American Institute of Chemical Engineers.

  12. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    International Nuclear Information System (INIS)

    Bae, Hyeun Jong; Wi, Seung Gon; Lee, Yoon Gyo; Kim, Ho Myung; Kim, Su Bae

    2011-10-01

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. The 2nd year Research scope includes: 1) Optimization of pre-treatment conditions for enzymatic hydrolysis of lignocellulosic biomass and 2) Demonstration of enzymatic hydrolysis by recombinant enzymes. To optimize the pretreatment, we applied two processes: a wet process (wet milling + popping), and dry process (popping + dry milling). Out of these, the wet process presented the best glucose yield with a 93.1% conversion, while the dry process yielded 69.6%, and the unpretreated process yielded <20%. The recombinant cellulolytic enzymes showed very high specific activity, about 80-1000 times on CMC and 13-70 times on filter paper at pH 3.5 and 55 .deg. C

  13. Comparison of sodium carbonate pretreatment for enzymatic hydrolysis of wheat straw stem and leaf to produce fermentable sugars.

    Science.gov (United States)

    Jin, Yongcan; Huang, Ting; Geng, Wenhui; Yang, Linfeng

    2013-06-01

    The specific characteristics of biomass structure and chemical composition of straw stem and leaf may result in different behavior of pretreatment and enzymatic hydrolysis. In this work, sodium carbonate (SC) was employed as a pretreatment to improve the enzymatic digestibility of wheat straw. The chemical composition and enzymatic hydrolysis of wheat straw stem and leaf (sheath included) were investigated comparatively. Most of the polysaccharides are kept in the solid fractions after SC pretreatment, while the stem has better delignification selectivity than leaf at high temperature. The enzymatic hydrolysis efficiency of wheat straw leaf is significantly higher than that of stem. The maximum total sugar yield from SC pretreated leaf was about 16% higher than stem. The results show that sodium carbonate is of great potential to be used as a pretreatment for the production of bioethanol from straw handling waste in a straw pulp mill with a low feedstock cost. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Kinetics of Enzymatic High-Solid Hydrolysis of Lignocellulosic Biomass Studied by Calorimetry

    DEFF Research Database (Denmark)

    Olsen, Søren Nymand; Rasmussen, Erik Lumby; McFarland, K.C.

    2011-01-01

    analysis of the interrelationships of enzyme load and the rate, time, and extent of the reaction. The results suggest that the hydrolysis rate of pretreated corn stover is limited initially by available attack points on the substrate surface (conversion) but becomes proportional to enzyme dosage......Enzymatic hydrolysis of high-solid biomass (>10% w/w dry mass) has become increasingly important as a key step in the production of second-generation bioethanol. To this end, development of quantitative real-time assays is desirable both for empirical optimization and for detailed kinetic analysis...... rate with a detection limit of about 500 pmol glucose s−1. Hence, calorimetry is shown to be a highly sensitive real-time method, applicable for high solids, and independent on the complexity of the substrate. Dose–response experiments with a typical cellulase cocktail enabled a multidimensional...

  15. Pungent Components from Thioglucosides in Armoracia rusticana Grown in China, Obtained by Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Rong Li

    2006-01-01

    Full Text Available The conditions of enzymatic hydrolysis of thioglucosides, which are the precursors of the pungent components in Armoracia rusticana grown in China, were studied. The effects of incubation time, temperature, pH and the addition of ascorbic acid on the hydrolysis of thioglucosides were determined. The optimum hydrolytic conditions for the pungent components from thioglucosides were time, 120 min; temperature, 65 oC; pH=4.0 and ascorbic acid, 2 mg/g. The mixture of pungent components in a pale-yellow liquid and a yield of 0.85 % were isolated and analyzed by GC/MS. Nine constituents were identified, representing 92.1 % of the pungent components. The major constituents were allyl isothiocyanate (78.4 %, 3-butenyl isothiocyanate (1.5 %, 2-pentyl isothiocyanate (2.1 % and β-phenylethyl isothiocyanate (9.4 %.

  16. Comparison of steam and ammonia pretreatment for enzymatic hydrolysis of cellulose

    Energy Technology Data Exchange (ETDEWEB)

    Mes-Hartree, M.; Dale, B.E.; Craig, W.K.

    1988-11-01

    Aspenwood, wheat straw, wheat chaff and alfalfa stems were treated under pressure with either steam or ammonia. The material was then water or methanol/water extracted. The extent of enzymatic hydrolysis of the cellulose portion of the treated substrates was compared using two different cellulases, a commercial preparation, Celluclast, and those from the fungus Trichoderma harzianum. Both steam and ammonia treatment enhanced the accessibility of the cellulose as measured by hydrolysis. Methanol extraction of steamed material generally reduced the access of the enzyme to the cellulose, whereas methanol extraction of ammonia-treated material increased accessibility. The optimum combinations of pretreatment and extraction method depended on the substrate and on the enzyme system; no treatment suitable for all situations could be selected.

  17. Improvement on sugar cane bagasse hydrolysis using enzymatic mixture designed cocktail.

    Science.gov (United States)

    Bussamra, Bianca Consorti; Freitas, Sindelia; Costa, Aline Carvalho da

    2015-01-01

    The aim of this work was to study cocktail supplementation for sugar cane bagasse hydrolysis, where the enzymes were provided from both commercial source and microorganism cultivation (Trichoderma reesei and genetically modified Escherichia coli), followed by purification. Experimental simplex lattice mixture design was performed to optimize the enzymatic proportion. The response was evaluated through hydrolysis microassays validated here. The optimized enzyme mixture, comprised of T. reesei fraction (80%), endoglucanase (10%) and β-glucosidase (10%), converted, theoretically, 72% of cellulose present in hydrothermally pretreated bagasse, whereas commercial Celluclast 1.5L converts 49.11%±0.49. Thus, a rational enzyme mixture designed by using synergism concept and statistical analysis was capable of improving biomass saccharification. Copyright © 2015 Elsevier Ltd. All rights reserved.

  18. BSA treatment to enhance enzymatic hydrolysis of cellulose in lignin containing substrates.

    Science.gov (United States)

    Yang, Bin; Wyman, Charles E

    2006-07-05

    Cellulase and bovine serum albumin (BSA) were added to Avicel cellulose and solids containing 56% cellulose and 28% lignin from dilute sulfuric acid pretreatment of corn stover. Little BSA was adsorbed on Avicel cellulose, while pretreated corn stover solids adsorbed considerable amounts of this protein. On the other hand, cellulase was highly adsorbed on both substrates. Adding a 1% concentration of BSA to dilute acid pretreated corn stover prior to enzyme addition at 15 FPU/g cellulose enhanced filter paper activity in solution by about a factor of 2 and beta-glucosidase activity in solution by about a factor of 14. Overall, these results suggested that BSA treatment reduced adsorption of cellulase and particularly beta-glucosidase on lignin. Of particular note, BSA treatment of pretreated corn stover solids prior to enzymatic hydrolysis increased 72 h glucose yields from about 82% to about 92% at a cellulase loading of 15 FPU/g cellulose or achieved about the same yield at a loading of 7.5 FPU/g cellulose. Similar improvements were also observed for enzymatic hydrolysis of ammonia fiber explosion (AFEX) pretreated corn stover and Douglas fir treated by SO(2) steam explosion and for simultaneous saccharification and fermentation (SSF) of BSA pretreated corn stover. In addition, BSA treatment prior to hydrolysis reduced the need for beta-glucosidase supplementation of SSF. The results are consistent with non-specific competitive, irreversible adsorption of BSA on lignin and identify promising strategies to reduce enzyme requirements for cellulose hydrolysis. (c) 2006 Wiley Periodicals, Inc.

  19. [Effects of hot-NaOH pretreatment on Jerusalem artichoke stalk composition and subsequent enzymatic hydrolysis].

    Science.gov (United States)

    Wang, Qing; Qiu, Jingwen; Li, Yang; Shen, Fei

    2015-10-01

    In order to explore the possibility of Jerusalem artichoke stalk for bioenergy conversion, we analyzed the main composition of whole stalk, pitch, and core of the stalk. Meanwhile, these parts were pretreated with different NaOH concentrations at 121 degrees C. Afterwards, enzymatic hydrolysis was performed to evaluate the pretreatment efficiency. Jerusalem artichoke stalk was characterized by relatively high lignin content (32.0%) compared with traditional crop stalks. The total carbohydrate content was close to that of crop stalks, but with higher cellulose content (40.5%) and lower hemicellulose (19.6%) than those of traditional crop stalks. After pretreatment, the lignin content in the whole stalk, pitch, and core decreased by 13.1%-13.4%, 8.3%-13.5%, and 19.9%-27.2%, respectively, compared with the unpretreated substrates. The hemicellulose content in the whole stalk, pitch, and core decreased 87.8%-96.9%, 87.6%-95.0%, and 74.0%-90.2%, respectively. Correspondingly, the cellulose content in the pretreated whole stalk, pitch, and core increased by 56.5%-60.2%, 52.2%-55.4%, and 62.7%-73.2%, respectively. Moreover, increase of NaOH concentration for pretreatment could improve the enzymatic hydrolysis of the whole stalk and pitch by 2.3-2.6 folds and 10.3-18.5 folds, respectively. The hydrolysis of pretreated stalk core decreased significantly as 2.0 mol/L NaOH was employed, although the increased NaOH concentration can also improve its hydrolysis performance. Based on these results, hot-NaOH can be regarded as an option for Jerusalem artichoke stalk pretreatment. Increasing NaOH concentration was beneficial to hemicellulose and lignin removal, and consequently improved sugar conversion. However, the potential decrease of sugar conversion of the pretreated core by higher NaOH concentration suggested further optimization on the pretreatment conditions should be performed.

  20. Optimization of enzymatic hydrolysis of guar gum using response surface methodology

    OpenAIRE

    Mudgil, Deepak; Barak, Sheweta; Khatkar, B. S.

    2012-01-01

    Guar gum is a polysaccharide obtained from guar seed endosperm portion. Enzymatically hydrolyzed guar gum is low in viscosity and has several health benefits as dietary fiber. In this study, response surface methodology was used to determine the optimum conditions for hydrolysis that give minimum viscosity of guar gum. Central composite was employed to investigate the effects of pH (3–7), temperature (20–60 °C), reaction time (1–5 h) and cellulase concentration (0.25–1.25 mg/g) on viscosity d...

  1. Microwaves as a pretreatment for enhancing enzymatic hydrolysis of pineapple industrial waste for bioethanol production

    OpenAIRE

    Conesa Domínguez, Claudia; Seguí Gil, Lucía; Laguarda-Miro, Nicolas; Fito Maupoey, Pedro

    2016-01-01

    [EN] The pineapple industry generates significant amounts of residues which are classified as lignocellulosic residual biomass. In the present paper, microwaves are studied as a pretreatment to improve pineapple waste saccharification. Different microwave (MW) powers (10.625, 8.5, 6.375, 4.25 and 2.125 W/g) and exposure times (1-20 min) were applied to the solid part of the waste before enzymatic hydrolysis. Infrared thermography was used to assess temperature evolution and structural modific...

  2. Mathematical model for enzymatic hydrolysis and fermentation of cellulose by Trichoderma

    Energy Technology Data Exchange (ETDEWEB)

    Peitersen, N; Ross, Jr, E W

    1979-06-01

    This paper describes a mathematical model for the enzymatic hydrolysis and fermentation of cellulose by Trichoderma reesei. The principal features of the model are the assumption of two forms of cellulose (crystalline and amorphous), two sugars (cellobiose and glucose), and two enzymes (cellulase and ..beta..-glucosidase). An inducer-repressor-messenger RNA mechanism is used to predict enzyme formation, and pH effects are included. The model consists of 12 ordinary differential equations for 12 state variables and contains 38 parameters. The parameters were estimated from four sets of experimental data by optimization. The results appear satisfactory, and the computer programs permit simulation of a variety of system changes.

  3. Radiation pre-treatment of cellulose materials for the enhancement of enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Ardica, S.; Calderaro, E.; Cappadona, C.

    1984-01-01

    The effect of γ-ray pre-irradiation of cotton cellulose on glucose production on enzymatic hydrolysis by cellulase has been investigated. Pure cotton has been irradiated in air, in water and in acetate buffer solution over the dose range 10 3 to 10 6 Gy. Pre-irradiation in water or in acetate buffer solution is more effective than in air. The results show that the glucose yield is not always an increasing function of dose, and that for some dose levels, the glucose yields from the irradiated samples are lower than those from non-irradiated samples. (author)

  4. Optimization of enzymatic hydrolysis for ethanol production by simultaneous saccharification and fermentation of wastepaper.

    Science.gov (United States)

    Sangkharak, Kanokphorn

    2011-11-01

    The present study investigated the development of high sugar production by optimization of an enzymatic hydrolysis process using both conventional and statistical methods, as well as the production of ethanol by the selected wastepaper source. Among four sources of pretreated wastepaper including office paper, newspaper, handbills and cardboard, office paper gave the highest values of cellulose (87.12%) and holocelluloses (89.07%). The effects of the amount of wastepaper, the pretreatment method and the type of enzyme on reducing sugar production from office paper were studied using conventional methods. The highest reducing sugar production (1851.28 µg L(-1); 37.03% conversion of glucose) was obtained from the optimal condition containing 40 mg of office paper, pretreated with stream explosion and hydrolysed with the combination of cellulase from Aspergillus niger and Trichoderma viride at the fixed loading rate of 20 FPU g(-1) sample. The effects of interaction of wastepaper amount and enzyme concentration as well as incubation time were studied by a statistical method using central composite design. The optimal medium composition consisted of 43.97 µg L(-1), 28.14 FPU g(-1) sample and 53.73 h of wastepaper, enzyme concentration and incubation time, respectively, and gave the highest amount of sugar production (2184.22 µg L(-1)) and percentage conversion of glucose (43.68%). The ethanol production from pretreated office paper using Saccharomyces cerevisiae in a simultaneous saccharification and fermentation process was 21.02 g L(-1) after 36 h of cultivation, corresponding to an ethanol volumetric production rate of 0.58 g ethanol L(-1) h(-1).

  5. Pretreatment and enzymatic hydrolysis of wheat straw (Triticum aestivum L.) – The impact of lignin relocation and plant tissues on enzymatic accessibility

    DEFF Research Database (Denmark)

    Hansen, Mads Anders Tengstedt; Kristensen, Jan Bach; Felby, Claus

    2011-01-01

    , after 144 h of enzymatic hydrolysis the cortex had vanished, exposing the heavier lignified vascular tissue. Accumulation of lignin droplets and exposure of residual lignin could be part of the explanation for the decreasing hydrolysis rate. Flattening of macrofibrils after pretreatment together...... with more indentations on the surfaces was also observed, possibly caused by a proposed synergistic effect of cellobiohydrolases and endoglucanases. Keywords: Lignocellulose; Plant tissues; Lignin accumulation; Atomic Force Microscopy; Scanning Electron Microscopy...

  6. Heat integration of an ethanol polygeneration plant based on lignocellulose: Comparing weak acid hydrolysis and enzymatic hydrolysis; Energiintegrerat etanolkombinat baserat paa lignocellulosa - Jaemfoerelse mellan svagsyrahydrolys och enzymhydrolys

    Energy Technology Data Exchange (ETDEWEB)

    Olsson, Marcus; Nordman, Roger; Taherzadeh, Mohammad

    2011-07-01

    Plants for bioethanol production have been planned in several cities in Sweden, including Boraas. This report provides answers to general questions regarding how such a facility's energy demand is affected by the external integration with a heat and power plant and the internal energy integration between process units. Heat integration of a bioethanol plant means that energy is reused as much as is technically possible; this sets a practical minimum level for the energy demand of the plant. In the study, ethanol production from cellulose has been simulated using Aspen Plus. Weak acid hydrolysis and enzymatic hydrolysis have been simulated, each with 50,000 and 100,000 tonnes of ethanol per year, resulting in four simulation cases. In all cases, heat integration is evaluated using pinch analysis. The steam in the ethanol plant has been covered by steam from a heat and power plant similar to that found today in Boraas. It is important to note that the energy quotas reported here includes energy use for upgrading the residual products. This leads to lower energy quotas than would be the case if the upgrading of residuals were allocated outside of the ethanol production. The conclusions from the project are: - The steam demand of the ethanol plant leads to a reduction in both the electricity and heat production of the heat and power plant. For the weak acid hydrolysis, the electricity loss is relatively high, 26-98%, which will affect the revenue significantly. The loss of electricity production is lower for the enzymatic process: 11-47%. - The difference in decreased electricity between the theoretical case of heating the raw material and the two alternative heating cases is about a factor of two, so the design of the heating of raw material is extremely important. - The reduced heat output of the power plant can, in most cases, be balanced by the surplus heat from the ethanol plant, but to completely balance the shortage, heat over 100 deg C must be used

  7. Effect of the molecular structure of lignin-based polyoxyethylene ether on enzymatic hydrolysis efficiency and kinetics of lignocelluloses.

    Science.gov (United States)

    Lin, Xuliang; Qiu, Xueqing; Zhu, Duming; Li, Zihao; Zhan, Ningxin; Zheng, Jieyi; Lou, Hongming; Zhou, Mingsong; Yang, Dongjie

    2015-10-01

    Effect of the molecular structure of lignin-based polyoxyethylene ether (EHL-PEG) on enzymatic hydrolysis of Avicel and corn stover was investigated. With the increase of PEG contents and molecular weight of EHL-PEG, glucose yield of corn stover increased. EHL-PEG enhanced enzymatic hydrolysis of corn stover significantly at buffer pH 4.8-5.5. Glucose yield of corn stover at 20% solid content increased from 32.8% to 63.8% by adding EHL-PEG, while that with PEG4600 was 54.2%. Effect of EHL-PEG on enzymatic hydrolysis kinetics of cellulose film was studied by quartz crystal microbalance with dissipation monitoring (QCM-D) and atomic force microscopy (AFM). An enhancing mechanism of EHL-PEG on enzymatic hydrolysis kinetics of cellulose was proposed. Cellulase aggregates dispersed by EHL-PEG excavated extensive cavities into the surface of cellulose film, making the film become more loose and exposed. After the maximum enzymatic hydrolysis rate, the film was mainly peeled off layer by layer until equilibrium. Copyright © 2015 Elsevier Ltd. All rights reserved.

  8. Starch Spherulites Prepared by a Combination of Enzymatic and Acid Hydrolysis of Normal Corn Starch.

    Science.gov (United States)

    Shang, Yaqian; Chao, Chen; Yu, Jinglin; Copeland, Les; Wang, Shuo; Wang, Shujun

    2018-06-13

    This paper describes a new method to prepare spherulites from normal corn starch by a combination of enzymatic (mixtures of α-amylase and amyloglucosidase) and acid hydrolysis followed by recrystallization of the hydrolyzed products. The resulting spherulites contained a higher proportion of chains with a degree of polymerization (DP) of 6-12 and a lower proportion of chains with DP of 25-36, compared to those of native starch. The spherulites had an even particle size of about 2 μm and a typical B-type crystallinity. The amounts of long- and short-range molecular order of double helices in starch spherulites were larger, but the quality of starch crystallites was poorer, compared to that of native starch. This study showed an efficient method for preparing starch spherulites with uniform granule morphology and small particle size from normal corn starch. The ratios of α-amylase and amyloglucosidase in enzymatic hydrolysis had little effect on the structure of the starch spherulites.

  9. Chondroitin sulphate extracted from antler cartilage using high hydrostatic pressure and enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Chong-Tai Kim

    2014-12-01

    Full Text Available Chondroitin sulphate (CS, a major glycosaminoglycan, is an essential component of the extracellular matrix in cartilaginous tissues. Wapiti velvet antlers are a rich source of these molecules. The purpose of the present study was to develop an effective isolation procedure of CS from fresh velvet antlers using a combination of high hydrostatic pressure (100 MPa and enzymatic hydrolysis (papain. High CS extractability (95.1 ± 2.5% of total uronic acid was obtained following incubation (4 h at 50 °C with papain at pH 6.0 in 100 MPa compared to low extractability (19 ± 1.1% in ambient pressure (0.1 MPa. Antler CS fractions were isolated by Sephacryl S-300 chromatography and identified by western blot using an anti-CS monoclonal antibody. The antler CS fraction did not aggregate with hyaluronic acid in CL-2B chromatography and possessed DPPH radical scavenging activity at 78.3 ± 1.5%. The results indicated that high hydrostatic pressure and enzymatic hydrolysis procedure may be a useful tool for the isolation of CS from antler cartilaginous tissues.

  10. Improvement Enzymatic Hydrolysis of Wheat Straw for Bioethanol Production by Combined Treatment of Radiation and Acid

    International Nuclear Information System (INIS)

    Hong, Sung Hyun; Lee, Seung Sik; Bai, Hyoung Woo; Chung, Byung Yeoup

    2012-01-01

    The cost of ethanol production from starch and sucrose for use as a vehicle fuel is ultimately high. Consequently, it has been suggested that the large-scale use of ethanol as a fuel will require the utilization of cellulosic feedstock. Lignocellulosic biomass has the potential to serve as a low cost and renewable feedstock for bioconversion into fermentable sugars, which can be further utilized for biofuel production. It is estimated that there is over one billion tons of biomass available for conversion into biofuels on a renewable basis to displace a substantial portion of the fossil fuels currently consumed within the transportation sector. Among different pretreatment methods such as biological, physical, chemical, and physic-chemical pretreatments, chemical pretreatment using dilute acid as catalyst, which has been extensively evaluated for treating a variety of lignocellulosic feedstocks, is reported as one of the leading pretreatment technologies. Ionizing radiation can easily penetrate lignocellulosic structure and undoubtedly produce free radicals useful in modification of lignin structure as well as breakdown cellulose crystal regions. Phenoxy radicals appeared to be important radical intermediates that ultimately transformed into o-quinonoid structures in lignin. Therefore, ionizing radiation such as gamma ray and electron beam can be a great alternative. In this study, the effect of ionizing irradiation of wheat straw prior to dilute sulfuric acid treatment is investigated. The combined pretreatment for wheat straw was performed to evaluate the efficiency of enzymatic hydrolysis and compared with that of the effect of enzymatic hydrolysis by individual pretreatment

  11. A vertical ball mill as a new reactor design for biomass hydrolysis and fermentation process

    DEFF Research Database (Denmark)

    de Assis Castro, Rafael Cunha; Mussatto, Solange I.; Conceicao Roberto, Inês

    2017-01-01

    A vertical ball mill (VBM) reactor was evaluated for use in biomass conversion processes. The effects of agitation speed (100–200 rpm), number of glass spheres (0–30 units) and temperature (40–46 °C) on enzymatic hydrolysis of rice straw and on glucose fermentation by a thermotolerant Kluyveromyces...

  12. Improvement of enzymatic hydrolysis and ethanol production from corn stalk by alkali and N-methylmorpholine-N-oxide pretreatments.

    Science.gov (United States)

    Cai, Ling-Yan; Ma, Yu-Long; Ma, Xiao-Xia; Lv, Jun-Min

    2016-07-01

    A combinative technology of alkali and N-methylmorpholine-N-oxide (NMMO) was used to pretreat corn stalk (CS) for improving the efficiencies of subsequent enzymatic hydrolysis and ethanol fermentation. The results showed that this strategy could not only remove hemicellulose and lignin but also decrease the crystallinity of cellulose. About 98.0% of enzymatic hydrolysis yield was obtained from the pretreated CS as compared with 46.9% from the untreated sample. The yield for corresponding ethanol yield was 64.6% while untreated CS was only 18.8%. Besides, xylose yield obtained from the untreated CS was only 11.1%, while this value was 93.8% for alkali with NMMO pretreated sample. These results suggest that a combination of alkali with 50% (wt/wt) NMMO solution may be a promising alternative for pretreatment of lignocellulose, which can increase the productions of subsequent enzymatic hydrolysis and ethanol fermentation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Effects of surface proteins and lipids on molecular structure, thermal properties, and enzymatic hydrolysis of rice starch

    Directory of Open Access Journals (Sweden)

    Pan HU

    Full Text Available Abstract Rice starches with different amylose contents were treated with sodium dodecyl sulfate (SDS to deplete surface proteins and lipids, and the changes in molecular structure, thermal properties, and enzymatic hydrolysis were evaluated. SDS treatment did not significantly change the molecular weight distribution, crystalline structure, short-range ordered degree, and gelatinization properties of starch, but significantly altered the pasting properties and increased the swelling power of starch. The removal of surface proteins and lipids increased the enzymatic hydrolysis and in vitro digestion of starch. The influences of removing surface proteins and lipids from starch on swelling power, pasting properties, and enzymatic hydrolysis were different among the various starches because of the differences in molecular structures of different starch styles. The aforementioned results indicated that removing the surface proteins and lipids from starch did not change the molecular structure but had significant effects on some functional properties.

  14. Hydrolysis of Miscanthus for bioethanol production using dilute acid presoaking combined with wet explosion pre-treatment and enzymatic treatment

    DEFF Research Database (Denmark)

    Sørensen, Annette; Teller, Philip Johan; Hilstrøm, Troels

    2008-01-01

    xylose prior to wet explosion. The acid presoaking extracted 63.2% xylose and 5.2% glucose. Direct enzymatic hydrolysis of the presoaked biomass was found to give only low sugar yields of 24-26% glucose. Wet explosion is a pre-treatment method that combines wet-oxidation and steam explosion. The effect...... of wet explosion on non-presoaked and presoaked Miscanthus was investigated using both atmospheric air and hydrogen peroxide as the oxidizing agent. All wet explosion pre-treatments showed to have a disrupting effect on the lignocellulosic biomass, making the sugars accessible for enzymatic hydrolysis......Miscanthus is a high yielding bioenergy crop. In this study we used acid presoaking, wet explosion, and enzymatic hydrolysis to evaluate the combination of the different pre-treatment methods for bioethanol production with Miscanthus. Acid presoaking is primarily carried out in order to remove...

  15. Effects of enzymatic hydrolysis and ultrasounds pretreatments on corn cob and vine trimming shoots for biogas production.

    Science.gov (United States)

    Pérez-Rodríguez, N; García-Bernet, D; Domínguez, J M

    2016-12-01

    Due to their lignocellulosic nature, corn cob and vine trimming shoots (VTS) could be valorized by anaerobic digestion for biogas production. To enhance the digestibility of substrates, pretreatments of lignocellulosic materials are recommended. The effect of enzymatic hydrolysis, ultrasounds pretreatments (US) and the combination of both was assayed in lignocellulosic composition, methane, and biogas yields. The pretreatments leaded to a reduction in lignin and an increase in neutral detergent soluble compounds making corn cob and VTS more amendable for biogas conversion. The US were negative for biogas production from both substrates and in particular strongly detrimental for VTS. On the opposite side, the enzymatic hydrolysis was certainly beneficial increasing 59.8% and 14.6% the methane production from VTS and corn cob, respectively. The prior application of US did not potentiate (or not sufficiently) the improvement in the methane production reflected by the enzymatic hydrolysis pretreatment of VTS and corn cob. Copyright © 2016 Elsevier Ltd. All rights reserved.

  16. Économie d'un procédé d'hydrolyse enzymatique et fermentation de la paille de blé pour la production d'alcool carburant Economics of a Process for Producing Alcohol Fuels by Enzymatic Hydrolysis and Fermentation of Wheat Straw

    Directory of Open Access Journals (Sweden)

    Arlie J. P.

    2006-11-01

    Full Text Available Après définition des grandes lignes d'un procédé de base d'hydrolyse-fermentation de la paille de blé, l'analyse de sensibilité montre que le rendement de l'hydrolyse a une grande importance sur les bilans énergétique et économique. Des rendements de l'ordre de 85 % permettent d'obtenir des valeurs d'investissement par tonne de pétrole économisée tout à fait comparables à celles obtenues par d'autres techniques de valorisation de la biomasse en alcool, telle la synthèse du méthanol obtenu après gazéification du bois à l'oxygène. The basic features of a process for production from cereal straw of an acetone-butanol mixture for use as a gasoline substitute are described. They include pretreatment and enzymatic hydrolysis of the substrate followed by fermentation of the sugars produced. A cost evaluation based on the performances of a reference process is presented. Then, an analysis of the sensitivity of the cost price of the process to the variation of the important parameters such as production capacity, enzyme productivity, hydrolysis yield is carried out. The energy balance of the process is presented.

  17. Assessment of cellulose purification methods from the residue of enzymatic hydrolysis of sugarcane bagasse for the production of cellulose nanocrystals

    International Nuclear Information System (INIS)

    Camargo, Lais Angelice de; Farinas, Cristiane Sanchez; Marconcini, José Manoel; Mattoso, Luiz Henrique Capparelli; Pereira, Sandra Cerqueira

    2016-01-01

    Full text: Over the years, there is a growing trend in the reuse of residues from the agricultural industries due to social, environmental and economic demands. The production of Brazilian sugarcane in the 2014/15 season was more than 640 million tons, estimating that one third of this total is bagasse [1]. After enzymatic hydrolysis of bagasse in order to give the 2G ethanol, remains a solid fibrous residue which can be repurposed in other processes. This study evaluated four methods for the purification of the resulting solid fibrous residue from the enzymatic hydrolysis process of bagasse, with the intention of obtaining cellulose. Measurements of the crystallinity index (CI) of the cellulose contained in the samples were determined using X-ray Diffraction (XRD). The enzymatic hydrolysis of generates a fibrous solid residue with contents of lignin and cellulose. This residue was subjected to four purification methods: I) 100 mL of NaOH (5%, w/w) at 55 °C was added to 5 g of residue and 43 mL of H 2 O 2 (35%, v/v) under stirring for 1.5 hours; II) the same procedure was repeated on the resulting material from I; III) 105 mL of solution 10:1 (ν/ν) of CH 3 COOH and HNO 3 at 60 °C was added to 5 g of residue under stirring for 30 minutes; IV) reaction with a solution composed of 1 ml of CH 3 COOH and 2.5 g of NaClO 2 at 70 °C under stirring for 1 hour and after that time, the procedure was repeated twice and then the solution was kept under stirring for further 3 hours. The crystallinity indexes found for the purification procedures were: I) 81.7%; II) 83.2%; III) 52.1% e IV) 77.2%. The best result was found for the material subjected to the method II. This process (II) generated a material composed of high content of crystalline cellulose. References: [1] CONAB (National Supply Company), 2015. (author)

  18. Temperature induced decoupling of enzymatic hydrolysis and carbon remineralization in long-term incubations of Arctic and temperate sediments

    DEFF Research Database (Denmark)

    Robador, Alberto; Brüchert, Volker; Steen, Andrew

    2010-01-01

    explored the temperature sensitivity of enzymatic hydrolysis and its connection to subsequent steps in anoxic organic carbon degradation in long-term incubations of sediments from the Arctic and the North Sea. These sediments were incubated under anaerobic conditions for 24 months at temperatures of 0, 10......, and 20 ºC. The short-term temperature response of the active microbial community was tested in temperature gradient block incubations. The temperature optimum of extracellular enzymatic hydrolysis, as measured with a polysaccharide (chondroitin sulfate), differed between Arctic and temperate habitats...

  19. Evaluation of lime and hydrothermal pretreatments for efficient enzymatic hydrolysis of raw sugarcane bagasse.

    Science.gov (United States)

    Grimaldi, Maira Prearo; Marques, Marina Paganini; Laluce, Cecília; Cilli, Eduardo Maffud; Sponchiado, Sandra Regina Pombeiro

    2015-01-01

    Ethanol production from sugarcane bagasse requires a pretreatment step to disrupt the cellulose-hemicellulose-lignin complex and to increase biomass digestibility, thus allowing the obtaining of high yields of fermentable sugars for the subsequent fermentation. Hydrothermal and lime pretreatments have emerged as effective methods in preparing the lignocellulosic biomass for bioconversion. These pretreatments are advantageous because they can be performed under mild temperature and pressure conditions, resulting in less sugar degradation compared with other pretreatments, and also are cost-effective and environmentally sustainable. In this study, we evaluated the effect of these pretreatments on the efficiency of enzymatic hydrolysis of raw sugarcane bagasse obtained directly from mill without prior screening. In addition, we evaluated the structure and composition modifications of this bagasse after lime and hydrothermal pretreatments. The highest cellulose hydrolysis rate (70 % digestion) was obtained for raw sugarcane bagasse pretreated with lime [0.1 g Ca(OH)2/g raw] for 60 min at 120 °C compared with hydrothermally pretreated bagasse (21 % digestion) under the same time and temperature conditions. Chemical composition analyses showed that the lime pretreatment of bagasse promoted high solubilization of lignin (30 %) and hemicellulose (5 %) accompanied by a cellulose accumulation (11 %). Analysis of pretreated bagasse structure revealed that lime pretreatment caused considerable damage to the bagasse fibers, including rupture of the cell wall, exposing the cellulose-rich areas to enzymatic action. We showed that lime pretreatment is effective in improving enzymatic digestibility of raw sugarcane bagasse, even at low lime loading and over a short pretreatment period. It was also demonstrated that this pretreatment caused alterations in the structure and composition of raw bagasse, which had a pronounced effect on the enzymes accessibility to the

  20. Double enzymatic hydrolysis preparation of heme from goose blood and microencapsulation to promote its stability and absorption.

    Science.gov (United States)

    Wang, Baowei; Cheng, Fansheng; Gao, Shun; Ge, Wenhua; Zhang, Mingai

    2017-02-15

    Iron deficiency anemia (IDA) is the most common nutritional deficiency worldwide. This deficiency could be solved by preparing stable, edible, and absorbable iron food ingredients using environmentally friendly methods. This study investigated enzymatic hydrolysis and microencapsulation process of goose blood. The physicochemical properties, stabilities of the microencapsulated goose blood hydrolysate (MGBH) and a supplement for rats with IDA were also evaluated. The results showed that the synergetic hydrolytic action of neutrase and alkaline protease significantly increased the heme-releasing efficiency. The heme was then microencapsulated using sodium caseinate, maltodextrin and carboxymethyl cellulose (CMC) as the edible wall material, and the encapsulation efficiency of the product reached 98.64%. Meanwhile, favorable thermal, storage and light stabilities were observed for the microencapsulation. It was found that MGBH can significantly improve the body weight and hematological parameters of IDA Wistar rat. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Optimization of aqueous enzymatic extraction of oil from shrimp processing by-products using response surface methodology

    Directory of Open Access Journals (Sweden)

    Chen WENWEI

    2018-06-01

    Full Text Available Abstract The aqueous enzymatic extraction (AEE of oil from shrimp processing by-products was investigated. Four kinds of proteases, including alkaline protease, neutral protease, flavor protease and compound protease, were applied to hydrolysis shrimp processing by-products. The results showed that flavor protease was the best hydrolysis enzyme for shrimp processing by-products to obtain high oil recovery. The influences of four factors, including enzyme amount, liquid/solid ratio, hydrolysis time and hydrolysis temperature, on shrimp oil extraction yield were also studied. The flavor enzyme hydrolysis condition was optimized as following: enzyme amount of 2.0% (w/w, liquid/solid ratio of 9.0ml/g, hydrolysis time of 2.6 h and hydrolysis temperature of 50 °C. Under these optimum hydrolysis conditions, the experimental oil extraction yield was 88.9%.

  2. Thermo-chemical pretreatment and enzymatic hydrolysis for enhancing saccharification of catalpa sawdust.

    Science.gov (United States)

    Jin, Shuguang; Zhang, Guangming; Zhang, Panyue; Li, Fan; Fan, Shiyang; Li, Juan

    2016-04-01

    To improve the reducing sugar production from catalpa sawdust, thermo-chemical pretreatments were examined and the chemicals used including NaOH, Ca(OH)2, H2SO4, and HCl. The hemicellulose solubilization and cellulose crystallinity index (CrI) were significantly increased after thermo-alkaline pretreatments, and the thermo-Ca(OH)2 pretreatment showed the best improvement for reducing sugar production comparing to other three pretreatments. The conditions of thermo-Ca(OH)2 pretreatment and enzymatic hydrolysis were systematically optimized. Under the optimal conditions, the reducing sugar yield increased by 1185.7% comparing to the control. This study indicates that the thermo-Ca(OH)2 pretreatment is ideal for the saccharification of catalpa sawdust and that catalpa sawdust is a promising raw material for biofuel. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Effect of gamma ray radiation pretreatment on enzymatic hydrolysis of wheat straw to produce sugar

    International Nuclear Information System (INIS)

    Yang Chunping; Shen Zhiqiang; Yu Guoce; Wang Jianlong

    2009-01-01

    The effect and aftereffect of radiation pretreatment of wheat straw with gamma ray were studied. It is shown that irradiation can cause significant breakdown of the structure of wheat straw. The mass loss of wheat straw increases and the size distribution after crushing moves to fine particles at elevated irradiation doses. A synergistic effect between irradiation and crushing was observed, with a glucose yield of 10.2% at a dose of 500 kGy with powder of 0.109 mm. The aftereffect of irradiation has important impact on enzymatic hydrolysis of wheat straw. The aftereffect of 400 kGy irradiation accounts for 20.1% of the initial effect for glucose production, and the aftereffects of 50, 100, 200 and 300 kGy account for 12.9%, 14.9%, 8.9% and 9.1%, respectively, for reducing sugar production. (authors)

  4. Enzymatic hydrolysis of loblolly pine: effects of cellulose crystallinity and delignification

    Science.gov (United States)

    Umesh P. Agarwal; J.Y. Zhu; Sally A. Ralph

    2013-01-01

    Hydrolysis experiments with commercial cellulases have been performed to understand the effects of cell wall crystallinity and lignin on the process. In the focus of the paper are loblolly pine wood samples, which were systematically delignified and partly ball-milled, and, for comparison, Whatman CC31 cellulose samples with different crystallinities. In pure cellulose...

  5. Production and effect of aldonic acids during enzymatic hydrolysis of lignocellulose at high dry matter content

    DEFF Research Database (Denmark)

    Cannella, David; Hsieh, Chia-Wen; Felby, Claus

    2012-01-01

    Abstract Background: The recent discovery of accessory proteins that boost cellulose hydrolysis has increased the economical and technical efficiency of processing cellulose to bioethanol. Oxidative enzymes (e.g. GH61) present in new commercial enzyme preparations have shown to increase cellulose...

  6. Yield-determining factors in high-solids enzymatic hydrolysis of lignocellulose

    Directory of Open Access Journals (Sweden)

    Felby Claus

    2009-06-01

    Full Text Available Abstract Background Working at high solids (substrate concentrations is advantageous in enzymatic conversion of lignocellulosic biomass as it increases product concentrations and plant productivity while lowering energy and water input. However, for a number of lignocellulosic substrates it has been shown that at increasing substrate concentration, the corresponding yield decreases in a fashion which can not be explained by current models and knowledge of enzyme-substrate interactions. This decrease in yield is undesirable as it offsets the advantages of working at high solids levels. The cause of the 'solids effect' has so far remained unknown. Results The decreasing conversion at increasing solids concentrations was found to be a generic or intrinsic effect, describing a linear correlation from 5 to 30% initial total solids content (w/w. Insufficient mixing has previously been shown not to be involved in the effect. Hydrolysis experiments with filter paper showed that neither lignin content nor hemicellulose-derived inhibitors appear to be responsible for the decrease in yields. Product inhibition by glucose and in particular cellobiose (and ethanol in simultaneous saccharification and fermentation at the increased concentrations at high solids loading plays a role but could not completely account for the decreasing conversion. Adsorption of cellulases was found to decrease at increasing solids concentrations. There was a strong correlation between the decreasing adsorption and conversion, indicating that the inhibition of cellulase adsorption to cellulose is causing the decrease in yield. Conclusion Inhibition of enzyme adsorption by hydrolysis products appear to be the main cause of the decreasing yields at increasing substrate concentrations in the enzymatic decomposition of cellulosic biomass. In order to facilitate high conversions at high solids concentrations, understanding of the mechanisms involved in high-solids product inhibition

  7. Bioethanol production from the nutrient stress-induced microalga Chlorella vulgaris by enzymatic hydrolysis and immobilized yeast fermentation.

    Science.gov (United States)

    Kim, Kyoung Hyoun; Choi, In Seong; Kim, Ho Myeong; Wi, Seung Gon; Bae, Hyeun-Jong

    2014-02-01

    The microalga Chlorella vulgaris is a potential feedstock for bioenergy due to its rapid growth, carbon dioxide fixation efficiency, and high accumulation of lipids and carbohydrates. In particular, the carbohydrates in microalgae make them a candidate for bioethanol feedstock. In this study, nutrient stress cultivation was employed to enhance the carbohydrate content of C. vulgaris. Nitrogen limitation increased the carbohydrate content to 22.4% from the normal content of 16.0% on dry weight basis. In addition, several pretreatment methods and enzymes were investigated to increase saccharification yields. Bead-beating pretreatment increased hydrolysis by 25% compared with the processes lacking pretreatment. In the enzymatic hydrolysis process, the pectinase enzyme group was superior for releasing fermentable sugars from carbohydrates in microalgae. In particular, pectinase from Aspergillus aculeatus displayed a 79% saccharification yield after 72h at 50°C. Using continuous immobilized yeast fermentation, microalgal hydrolysate was converted into ethanol at a yield of 89%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Over production of fermentable sugar for bioethanol production from carbohydrate-rich Malaysian food waste via sequential acid-enzymatic hydrolysis pretreatment.

    Science.gov (United States)

    Hafid, Halimatun Saadiah; Nor 'Aini, Abdul Rahman; Mokhtar, Mohd Noriznan; Talib, Ahmad Tarmezee; Baharuddin, Azhari Samsu; Umi Kalsom, Md Shah

    2017-09-01

    In Malaysia, the amount of food waste produced is estimated at approximately 70% of total municipal solid waste generated and characterised by high amount of carbohydrate polymers such as starch, cellulose, and sugars. Considering the beneficial organic fraction contained, its utilization as an alternative substrate specifically for bioethanol production has receiving more attention. However, the sustainable production of bioethanol from food waste is linked to the efficient pretreatment needed for higher production of fermentable sugar prior to fermentation. In this work, a modified sequential acid-enzymatic hydrolysis process has been developed to produce high concentration of fermentable sugars; glucose, sucrose, fructose and maltose. The process started with hydrothermal and dilute acid pretreatment by hydrochloric acid (HCl) and sulphuric acid (H 2 SO 4 ) which aim to degrade larger molecules of polysaccharide before accessible for further steps of enzymatic hydrolysis by glucoamylase. A kinetic model is proposed to perform an optimal hydrolysis for obtaining high fermentable sugars. The results suggested that a significant increase in fermentable sugar production (2.04-folds) with conversion efficiency of 86.8% was observed via sequential acid-enzymatic pretreatment as compared to dilute acid pretreatment (∼42.4% conversion efficiency). The bioethanol production by Saccharomyces cerevisiae utilizing fermentable sugar obtained shows ethanol yield of 0.42g/g with conversion efficiency of 85.38% based on the theoretical yield was achieved. The finding indicates that food waste can be considered as a promising substrate for bioethanol production. Copyright © 2017. Published by Elsevier Ltd.

  9. Biological pretreatment of corn stover with ligninolytic enzyme for high efficient enzymatic hydrolysis.

    Science.gov (United States)

    Wang, Feng-Qin; Xie, Hui; Chen, Wei; Wang, En-Tao; Du, Feng-Guang; Song, An-Dong

    2013-09-01

    Aiming at increasing the efficiency of transferring corn stover into sugars, a biological pretreatment was developed and investigated in this study. The protocol was characterized by the pretreatment with crude ligninolytic enzymes from Phanerochete chrysosporium and Coridus versicolor to break the lignin structure in corn stover, followed by a washing procedure to eliminate the inhibition of ligninolytic enzyme on cellulase. By a 2 d-pretreatment, sugar yield from corn stover hydrolysis could be increased by 50.2% (up to 323 mg/g) compared with that of the control. X-ray diffractometry and FT-IR analysis revealed that biological pretreatment could partially remove the lignin of corn stover, and consequently enhance the enzymatic hydrolysis efficiency of cellulose and hemeicellulose. In addition, the amount of microbial inhibitors, such as acetic acid and furfural, were much lower in biological pretreatment than that in acid pretreatment. This study provided a promising pretreatment method for biotransformation of corn stovers. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Co-solvent effects on reaction rate and reaction equilibrium of an enzymatic peptide hydrolysis.

    Science.gov (United States)

    Wangler, A; Canales, R; Held, C; Luong, T Q; Winter, R; Zaitsau, D H; Verevkin, S P; Sadowski, G

    2018-04-25

    This work presents an approach that expresses the Michaelis constant KaM and the equilibrium constant Kth of an enzymatic peptide hydrolysis based on thermodynamic activities instead of concentrations. This provides KaM and Kth values that are independent of any co-solvent. To this end, the hydrolysis reaction of N-succinyl-l-phenylalanine-p-nitroanilide catalysed by the enzyme α-chymotrypsin was studied in pure buffer and in the presence of the co-solvents dimethyl sulfoxide, trimethylamine-N-oxide, urea, and two salts. A strong influence of the co-solvents on the measured Michaelis constant (KM) and equilibrium constant (Kx) was observed, which was found to be caused by molecular interactions expressed as activity coefficients. Substrate and product activity coefficients were used to calculate the activity-based values KaM and Kth for the co-solvent free reaction. Based on these constants, the co-solvent effect on KM and Kx was predicted in almost quantitative agreement with the experimental data. The approach presented here does not only reveal the importance of understanding the thermodynamic non-ideality of reactions taking place in biological solutions and in many technological applications, it also provides a framework for interpreting and quantifying the multifaceted co-solvent effects on enzyme-catalysed reactions that are known and have been observed experimentally for a long time.

  11. Ammonia Fiber Expansion Pretreatment and Enzymatic Hydrolysis on Two Different Growth Stages of Reed Canarygrass

    Science.gov (United States)

    Bradshaw, Tamika C.; Alizadeh, Hasan; Teymouri, Farzaneh; Balan, Venkatesh; Dale, Bruce E.

    Plant materials from the vegetative growth stage of reed canarygrass and the seed stage of reed canarygrass are pretreated by ammonia fiber expansion (AFEX) and enzymatically hydrolyzed using 15 filter paper units (FPU) cellulase/g glucan to evaluate glucose and xylose yields. Percent conversions of glucose and xylose, effects of temperature and ammonia loading, and hydrolysis profiles are analyzed to determine the most effective AFEX treatment condition for each of the selected materials. The controls used in this study were untreated samples of each biomass material. All pretreatment conditions tested enhanced enzyme digestibility and improved sugar conversions for reed canarygrass compared with their untreated counterparts. Based on 168 h hydrolysis results using 15 FPU Spezyme CP cellulase/g glucan the most effective AFEX treatment conditions were determined as: vegetative growth stage of reed canarygrass—100°C, 60% moisture content, 1.2∶1 kg ammonia/kg of dry matter (86% glucose and 78% xylose) and seed stage of reed canarygrass—100°C, 60% moisture content, 0.8∶1 kg ammonia/kg of dry matter (89% glucose and 81% xylose). Supplementation by commercial Multifect 720 xylanase along with cellulase further increased both glucose and xylose yields by 10-12% at the most effective AFEX conditions.

  12. High-throughput microplate technique for enzymatic hydrolysis of lignocellulosic biomass.

    Science.gov (United States)

    Chundawat, Shishir P S; Balan, Venkatesh; Dale, Bruce E

    2008-04-15

    Several factors will influence the viability of a biochemical platform for manufacturing lignocellulosic based fuels and chemicals, for example, genetically engineering energy crops, reducing pre-treatment severity, and minimizing enzyme loading. Past research on biomass conversion has focused largely on acid based pre-treatment technologies that fractionate lignin and hemicellulose from cellulose. However, for alkaline based (e.g., AFEX) and other lower severity pre-treatments it becomes critical to co-hydrolyze cellulose and hemicellulose using an optimized enzyme cocktail. Lignocellulosics are appropriate substrates to assess hydrolytic activity of enzyme mixtures compared to conventional unrealistic substrates (e.g., filter paper, chromogenic, and fluorigenic compounds) for studying synergistic hydrolysis. However, there are few, if any, high-throughput lignocellulosic digestibility analytical platforms for optimizing biomass conversion. The 96-well Biomass Conversion Research Lab (BCRL) microplate method is a high-throughput assay to study digestibility of lignocellulosic biomass as a function of biomass composition, pre-treatment severity, and enzyme composition. The most suitable method for delivering milled biomass to the microplate was through multi-pipetting slurry suspensions. A rapid bio-enzymatic, spectrophotometric assay was used to determine fermentable sugars. The entire procedure was automated using a robotic pipetting workstation. Several parameters that affect hydrolysis in the microplate were studied and optimized (i.e., particle size reduction, slurry solids concentration, glucan loading, mass transfer issues, and time period for hydrolysis). The microplate method was optimized for crystalline cellulose (Avicel) and ammonia fiber expansion (AFEX) pre-treated corn stover. Copyright 2008 Wiley Periodicals, Inc.

  13. Forms and lability of phosphorus in algae and aquatic macrophytes characterized by solution 31P NMR coupled with enzymatic hydrolysis

    Science.gov (United States)

    Increased information on forms and lability of phosphorus (P) in aquatic macrophytes and algae is crucial for better understanding of P biogeochemical cycling in eutrophic lakes. In this work, solution 31P nuclear magnetic resonance (NMR) spectroscopy coupled with enzymatic hydrolysis (EH) was used ...

  14. Rapid enzymatic hydrolysis of masked deoxynivalenol and zearalenone prior to liquid chromatography mass spectrometry or immunoassay analysis

    Czech Academy of Sciences Publication Activity Database

    Nielen, M. F. V.; Weijers, C. A. G. M.; Peters, J.; Weignerová, Lenka; Zuilhof, H.; Franssen, M. C. R.

    2014-01-01

    Roč. 7, č. 2 (2014), s. 107-113 ISSN 1875-0710 Institutional support: RVO:61388971 Keywords : masked mycotoxins * enzymatic hydrolysis * 1,3-beta-glucanase Subject RIV: CE - Biochemistry Impact factor: 2.157, year: 2014

  15. Combining autohydrolysis and ionic liquid microwave treatment to enhance enzymatic hydrolysis of Eucalyptus globulus wood.

    Science.gov (United States)

    Rigual, Victoria; Santos, Tamara M; Domínguez, Juan Carlos; Alonso, M Virginia; Oliet, Mercedes; Rodriguez, Francisco

    2018-03-01

    The combination of autohydrolysis and ionic liquid microwave treatments of eucalyptus wood have been studied to facilitate sugar production in a subsequent enzymatic hydrolysis step. Three autohydrolysis conditions (150 °C, 175 °C and 200 °C) in combination with two ionic liquid temperatures (80 °C and 120 °C) were compared in terms of chemical composition, enzymatic digestibility and sugar production. Morphology was measured (using SEM) and the biomass surface was visualized with confocal fluorescence microscopy. The synergistic cooperation of both treatments was demonstrated, enhancing cellulose accessibility. At intermediate autohydrolysis conditions (175 °C) and low ionic liquid temperature (80 °C), a glucan digestibility of 84.4% was obtained. Using SEM micrographs, fractal dimension (as a measure of biomass complexity) and lacunarity (as a measure of homogeneity) were calculated before and after pretreatment. High fractals dimensions and low lacunarities correspond to morphologically complex and homogeneous samples, that are better digested by enzyme cocktails. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Kinetic Modelling and Experimental Studies for the Effects of Fe2+ Ions on Xylan Hydrolysis with Dilute-Acid Pretreatment and Subsequent Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Hui Wei

    2018-01-01

    Full Text Available High-temperature (150–170 °C pretreatment of lignocellulosic biomass with mineral acids is well established for xylan breakdown. Fe2+ is known to be a cocatalyst of this process although kinetics of its action remains unknown. The present work addresses the effect of ferrous ion concentration on sugar yield and degradation product formation from corn stover for the entire two-step treatment, including the subsequent enzymatic cellulose hydrolysis. The feedstock was impregnated with 0.5% acid and 0.75 mM iron cocatalyst, which was found to be optimal in preliminary experiments. The detailed kinetic data of acid pretreatment, with and without iron, was satisfactorily modelled with a four-step linear sequence of first-order irreversible reactions accounting for the formation of xylooligomers, xylose and furfural as intermediates to provide the values of Arrhenius activation energy. Based on this kinetic modelling, Fe2+ turned out to accelerate all four reactions, with a significant alteration of the last two steps, that is, xylose degradation. Consistent with this model, the greatest xylan conversion occurred at the highest severity tested under 170 °C/30 min with 0.75 mM Fe2+, with a total of 8% xylan remaining in the pretreated solids, whereas the operational conditions leading to the highest xylose monomer yield, 63%, were milder, 150 °C with 0.75 mM Fe2+ for 20 min. Furthermore, the subsequent enzymatic hydrolysis with the prior addition of 0.75 mM of iron(II increased the glucose production to 56.3% from 46.3% in the control (iron-free acid. The detailed analysis indicated that conducting the process at lower temperatures yet long residence times benefits the yield of sugars. The above kinetic modelling results of Fe2+ accelerating all four reactions are in line with our previous mechanistic research showing that the pretreatment likely targets multiple chemistries in plant cell wall polymer networks, including those represented by the C

  17. Effect and Modeling of Glucose Inhibition and In Situ Glucose Removal During Enzymatic Hydrolysis of Pretreated Wheat Straw

    DEFF Research Database (Denmark)

    Andric, Pavle; Meyer, Anne S.; Jensen, Peter Arendt

    2010-01-01

    The enzymatic hydrolysis of lignocellulosic biomass is known to be product-inhibited by glucose. In this study, the effects on cellulolytic glucose yields of glucose inhibition and in situ glucose removal were examined and modeled during extended treatment of heat-pretreated wheat straw......, during 96 h of reaction. When glucose was removed by dialysis during the enzymatic hydrolysis, the cellulose conversion rates and glucose yields increased. In fact, with dialytic in situ glucose removal, the rate of enzyme-catalyzed glucose release during 48-72 h of reaction recovered from 20......-40% to become approximate to 70% of the rate recorded during 6-24 h of reaction. Although Michaelis-Menten kinetics do not suffice to model the kinetics of the complex multi-enzymatic degradation of cellulose, the data for the glucose inhibition were surprisingly well described by simple Michaelis...

  18. Effects of acid impregnated steam explosion process on xylose recovery and enzymatic conversion of cellulose in corncob.

    Science.gov (United States)

    Fan, Xiaoguang; Cheng, Gang; Zhang, Hongjia; Li, Menghua; Wang, Shizeng; Yuan, Qipeng

    2014-12-19

    Corncob residue is a cellulose-rich byproduct obtained from industrial xylose production via dilute acid hydrolysis processes. Enzymatic hydrolysis of cellulose in acid hydrolysis residue of corncob (AHRC) is often less efficient without further pretreatment. In this work, the process characteristics of acid impregnated steam explosion were studied in conjunction with a dilute acid process, and their effects on physiochemical changes and enzymatic saccharification of corncob residue were compared. With the acid impregnated steam explosion process, both higher xylose recovery and higher cellulose conversion were obtained. The maximum conversion of cellulose in acid impregnated steam explosion residue of corncob (ASERC) reached 85.3%, which was 1.6 times higher than that of AHRC. Biomass compositional analysis showed similar cellulose and lignin content in ASERC and AHRC. XRD analysis demonstrated comparable crystallinity of ASERC and AHRC. The improved enzymatic hydrolysis efficiency was attributed to higher porosity in ASERC, measured by mercury porosimetry. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Comparison of different pretreatment strategies for enzymatic hydrolysis of wheat and barley straw

    DEFF Research Database (Denmark)

    Rosgaard, Lisa; Pedersen, Sven; Meyer, Anne Boye Strunge

    2007-01-01

    In biomass-to-ethanol processes a physico-chemical pretreatment of the lignocellulosic biomass is a critical requirement for enhancing the accessibility of the cellulose substrate to enzymatic attack. This report evaluates the efficacy on barley and wheat straw of three different pretreatment pro...

  20. Ammonia fiber expansion (AFEX) pretreatment, enzymatic hydrolysis, and fermentation on empty palm fruit bunch fiber (EPFBF) for cellulosic ethanol production.

    Science.gov (United States)

    Lau, Ming J; Lau, Ming W; Gunawan, Christa; Dale, Bruce E

    2010-11-01

    Empty palm fruit bunch fiber (EPFBF), a readily available cellulosic biomass from palm processing facilities, is investigated as a potential carbohydrate source for cellulosic ethanol production. This feedstock was pretreated using ammonia fiber expansion (AFEX) and enzymatically hydrolyzed. The best tested AFEX conditions were at 135 °C, 45 min retention time, water to dry biomass loading of 1:1 (weight ratio), and ammonia to dry biomass loading of 1:1 (weight ratio). The particle size of the pretreated biomass was reduced post-AFEX. The optimized enzyme formulation consists of Accellerase (84 μL/g biomass), Multifect Xylanase (31 μL/g biomass), and Multifect Pectinase (24 μL/g biomass). This mixture achieved close to 90% of the total maximum yield within 72 h of enzymatic hydrolysis. Fermentation on the water extract of this biomass affirms that nutrients solely from the pretreated EPFBF can support yeast growth for complete glucose fermentation. These results suggest that AFEX-treated EPFBF can be used for cellulosic biofuels production because biomass recalcitrance has been overcome without reducing the fermentability of the pretreated materials.

  1. Physicochemical and sensory characterization of refined and deodorized tuna (Thunnus albacares) by-product oil obtained by enzymatic hydrolysis.

    Science.gov (United States)

    de Oliveira, Dayse A S B; Minozzo, Marcelo G; Licodiedoff, Silvana; Waszczynskyj, Nina

    2016-09-15

    In this study, the effects of chemical refining and deodorization on fatty acid profiles and physicochemical and sensory characteristics of the tuna by-product oil obtained by enzymatic hydrolysis were evaluated. Enzymatic extraction was conducted for 120 min at 60 °C and pH 6.5 using Alcalase at an enzyme-substrate ratio of 1:200 w/w. The chemical refining of crude oil consisted of degumming, neutralization, washing, drying, bleaching, and deodorization; deodorization was conducted at different temperatures and processing times. Although chemical refining was successful, temperature and chemical reagents favored the removal of polyunsaturated fatty acids (PUFA) from the oil. Aroma attributes of fishy odor, frying odor, and rancid odor predominantly contributed to the sensory evaluation of the product. Deodorization conditions of 160 °C for 1h and 200 °C for 1h were recommended for the tuna by-product oil, which is rich in PUFA. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Electron beam processing of sugar cane bagasse to cellulose hydrolysis

    International Nuclear Information System (INIS)

    Ribeiro, Marcia A.; Cardoso, Vanessa M.; Mori, Manoel N.; Duarte, Celina L.

    2009-01-01

    Sugarcane bagasse has been considered as a substrate for single cell protein, animal feed, and renewable energy production. Sugarcane bagasse generally contain up to 45% glucose polymer cellulose, 40% hemicelluloses, and 20% lignin. Pure cellulose is readily depolymerised by radiation, but in biomass, the cellulose is intimately bonded with lignin, that protect it from radiation effects. The objective of this study is the evaluation of the electron beam irradiation as a pre-treatment to enzymatic hydrolysis of cellulose in order to facilitate its fermentation and improves the production of ethanol biofuel. Samples of sugarcane bagasse were obtained in sugar/ethanol Iracema Mill sited in Piracicaba, Brazil, and were irradiated using Radiation Dynamics Electron Beam Accelerator with 1.5 MeV energy and 37kW, in batch systems. The applied absorbed doses of the fist sampling, Bagasse A, were 20 kGy, 50 kGy, 100 kGy and 200 kGy. After the evaluation the preliminary obtained results, it was applied lower absorbed doses in the second assay: 5 kGy, 10 kGy, 20 kGy, 30 kGy, 50 kGy, 70 kGy, 100 kGy and 150 kGy. The electron beam processing took to changes in the sugarcane bagasse structure and composition, lignin and cellulose cleavage. The yield of enzymatic hydrolyzes of cellulose increase about 40 % with 30 kGy of absorbed dose. (author)

  3. In-depth investigation of enzymatic hydrolysis of biomass wastes based on three major components: Cellulose, hemicellulose and lignin.

    Science.gov (United States)

    Lin, Lili; Yan, Rong; Liu, Yongqiang; Jiang, Wenju

    2010-11-01

    The artificial biomass based on three biomass components (cellulose, hemicellulose and lignin) were developed on the basis of a simplex-lattice approach. Together with a natural biomass sample, they were employed in enzymatic hydrolysis researches. Different enzyme combines of two commercial enzymes (ACCELLERASE 1500 and OPTIMASH BG) showed a potential to hydrolyze hemicellulose completely. Negligible interactions among the three components were observed, and the used enzyme ACCELLERASE 1500 was proven to be weak lignin-binding. On this basis, a multiple linear-regression equation was established for predicting the reducing sugar yield based on the component proportions in a biomass. The hemicellulose and cellulose in a biomass sample were found to have different contributions in staged hydrolysis at different time periods. Furthermore, the hydrolysis of rice straw was conducted to validate the computation approach through considerations of alkaline solution pretreatment and combined enzymes function, so as to understand better the nature of biomass hydrolysis, from the aspect of three biomass components.

  4. HYDROLYSIS OF AGRICULTURAL BIOMASS BY COMBINED PRETREATMENT AND ENZYMATIC METHODS IN ORDER TO PRODUCE BIOFUELS (ETHANOL, BIOGAS

    Directory of Open Access Journals (Sweden)

    STEFANA JURCOANE

    2009-05-01

    Full Text Available The use of energy crops (maize straw, wheat straw, barley straw etc. as substrate for renewable energy production (e.g. biogas is more efficient when it is degraded by different hydrolysis methods. However, fibers contained inside energy crops (e.g. cellulose and hemicellulose are only hardly and slowly degraded by anaerobic bacteria. The slow degradation of these substances can decrease the methane yields of agricultural biogas plants.In the present study, we investigated the efficiency of combined pretreatment (different concentrations H2SO4 + 30 minutes at 1210C followed to enzymatic hydrolysis. Testing different concentration of H2SO4, good results were obtained for maize whole crop when we used combined pretreatment (3% H2SO4 + 30 minutes at 1210C followed to enzymatic hydrolysis (3.9 fold higher and for Gavott Maize Straw when we used combined pretreatment (2% H2SO4 + 30 minutes at 1210C followed to enzymatic hydrolysis (3.6 fold higher comparing with untreated samples.

  5. Improvement of the enzymatic hydrolysis of furfural residues by pretreatment with combined green liquor and ethanol organosolv.

    Science.gov (United States)

    Yu, Hailong; Xing, Yang; Lei, Fuhou; Liu, Zhiping; Liu, Zuguang; Jiang, Jianxin

    2014-09-01

    Furfural residues (FRs) were pretreated with ethanol and a green liquor (GL) catalyst to produce fermentable sugar. Anthraquinone (AQ) was used as an auxiliary reagent to improve delignification and reduce cellulose decomposition. The results showed that 42.7% of lignin was removed and 96.5% of cellulose was recovered from substrates pretreated with 1.0 mL GL/g of dry substrate and 0.4% (w/w) AQ at 140°C for 1h. Compared with raw material, ethanol-GL pretreatment of FRs increased the glucose yield from 69.0% to 85.9% after 96 h hydrolysis with 18 FPU/g-cellulose for cellulase, 27 CBU/g-cellulose for β-glucosidase. The Brauner-Emmett-Teller surface area was reduced during pretreatment, which did not inhibit the enzymatic hydrolysis. Owing to the reduced surface area, the unproductive binding of cellulase to lignin was decreased, thus improving the enzymatic hydrolysis. The degree of polymerization of cellulose from FRs was too low to be a key factor for improving enzymatic hydrolysis. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Pretreatment of wheat straw by nonionic surfactant-assisted dilute acid for enhancing enzymatic hydrolysis and ethanol production.

    Science.gov (United States)

    Qi, Benkun; Chen, Xiangrong; Wan, Yinhua

    2010-07-01

    Pretreating wheat straw (WS) with combined use of varied sulfuric acid concentration (0-3%, w/v) and Tween 20 concentration (0-1%) was investigated in an attempt to enhance the hydrolysis and fermentability of pretreated WS. Enzymatic hydrolysis yield of glucan and xylan and ethanol production by simultaneous saccharification and fermentation (SSF) of water-insoluble solids (WIS) were significantly affected by the amount of Tween 20 added during acid pretreatment. Any further addition of Tween 20 in either hydrolysis stage or fermentation stage only led to small increase in glucan conversion and ethanol production. Determination of adsorption of cellulases during hydrolysis showed that Tween 20-assisted acid treated straw solution contained more free cellulases than individual acid treated straw solution, indicating that modification of lignin surface by Tween 20 added during pretreatment likely occurred. In addition, the effects of pretreatment conditions on overall recovery of glucose and xylose after pretreatment and enzymatic hydrolysis were also investigated. Copyright 2010 Elsevier Ltd. All rights reserved.

  7. Effect of iron salt type and dosing mode on Fenton-based pretreatment of rice straw for enzymatic hydrolysis.

    Science.gov (United States)

    Gan, Yu-Yan; Zhou, Si-Li; Dai, Xiao; Wu, Han; Xiong, Zi-Yao; Qin, Yuan-Hang; Ma, Jiayu; Yang, Li; Wu, Zai-Kun; Wang, Tie-Lin; Wang, Wei-Guo; Wang, Cun-Wen

    2018-06-15

    Fenton-based processes with four different iron salts in two different dosing modes were used to pretreat rice straw (RS) samples to increase their enzymatic digestibility. The composition analysis shows that the RS sample pretreated by the dosing mode of iron salt adding into H 2 O 2 has a much lower hemicellulose content than that pretreated by the dosing mode of H 2 O 2 adding into iron salt, and the RS sample pretreated by the chloride salt-based Fenton process has a much lower lignin content and a slightly lower hemicellulose content than that pretreated by the sulphate salt-based Fenton process. The higher concentration of reducing sugar observed on the RS sample with lower lignin and hemicellulose contents justifies that the Fenton-based process could enhance the enzymic hydrolysis of RS by removing hemicellulose and lignin and increasing its accessibility to cellulase. FeCl 3 ·6H 2 O adding into H 2 O 2 is the most efficient Fenton-based process for RS pretreatment. Copyright © 2018 Elsevier Ltd. All rights reserved.

  8. Enhancing the enzymatic hydrolysis of corn stover by an integrated wet-milling and alkali pretreatment.

    Science.gov (United States)

    He, Xun; Miao, Yelian; Jiang, Xuejian; Xu, Zidong; Ouyang, Pingkai

    2010-04-01

    An integrated wet-milling and alkali pretreatment was applied to corn stover prior to enzymatic hydrolysis. The effects of NaOH concentration in the pretreatment on crystalline structure, chemical composition, and reducing-sugar yield of corn stover were investigated, and the mechanism of increasing reducing-sugar yield by the pretreatment was discussed. The experimental results showed that the crystalline structure of corn stover was disrupted, and lignin was removed, while cellulose and hemicellulose were retained in corn stover by the pretreatment with 1% NaOH in 1 h. The reducing-sugar yield from the pretreated corn stovers increased from 20.2% to 46.7% when the NaOH concentration increased from 0% to 1%. The 1% NaOH pretreated corn stover had a holocellulose conversion of 55.1%. The increase in reducing-sugar yield was related to the crystalline structure disruption and delignification of corn stover. It was clarified that the pretreatment significantly enhanced the conversion of cellulose and hemicellulose in the corn stover to sugars.

  9. Enzymatic hydrolysis and production of bioethanol from common macrophytic green alga Ulva fasciata Delile.

    Science.gov (United States)

    Trivedi, Nitin; Gupta, Vishal; Reddy, C R K; Jha, Bhavanath

    2013-12-01

    The green seaweed Ulva which proliferates fast and occurs abundantly worldwide was used as a feedstock for production of ethanol following enzymatic hydrolysis. Among the different cellulases investigated for efficient saccharification, cellulase 22119 showed the highest conversion efficiency of biomass into reducing sugars than Viscozyme L, Cellulase 22086 and 22128. Pre-heat treatment of biomass in aqueous medium at 120°C for 1h followed by incubation in 2% (v/v) enzyme for 36 h at 45°C gave a maximum yield of sugar 206.82±14.96 mg/g. The fermentation of hydrolysate gave ethanol yield of 0.45 g/g reducing sugar accounting for 88.2% conversion efficiency. These values are substantially higher than those of reported so far for both agarophytes and carrageenophytes. It was also confirmed that enzyme can be used twice without compromising on the saccharification efficiency. The findings of this study reveal that Ulva can be a potential feedstock for bioethanol production. Copyright © 2013 Elsevier Ltd. All rights reserved.

  10. Enhancement of enzymatic hydrolysis of wheat straw by gamma irradiation–alkaline pretreatment

    International Nuclear Information System (INIS)

    Yin, Yanan; Wang, Jianlong

    2016-01-01

    Pretreatment of wheat straw with gamma irradiation and NaOH was performed to enhance the enzymatic hydrolysis of wheat straw for production of reducing sugar. The results showed that the irradiation of wheat straw at 50 kGy decreased the yield of reducing sugar, however, the reducing sugar yield increased with increasing dose from 50 kGy to 400 kGy. The irradiation of wheat straw at 100 kGy can significantly decrease NaOH consumption and treatment time. The reducing sugar yield could reach 72.67% after irradiation at 100 kGy and 2% NaOH treatment for 1 h. The combined pretreatment of wheat straw by gamma radiation and NaOH immersion can increase the solubilization of hemicellulose and lignin as well as the accessible surface area for enzyme molecules. - Highlights: • Pretreatment of wheat straw by gamma radiation and NaOH was investigated. • Irradiation pretreatment can significantly decrease NaOH consumption. • Reducing sugar yield reached 72.67% at 100 kGy and 2% NaOH treatment for 1 h.

  11. Pretreatment of Dried Distiller Grains with Solubles by Soaking in Aqueous Ammonia and Subsequent Enzymatic/Dilute Acid Hydrolysis to Produce Fermentable Sugars.

    Science.gov (United States)

    Nghiem, Nhuan P; Montanti, Justin; Kim, Tae Hyun

    2016-05-01

    Dried distillers grains with solubles (DDGS), a co-product of corn ethanol production in the dry-grind process, was pretreated by soaking in aqueous ammonia (SAA) using a 15 % w/w NH4OH solution at a solid/liquid ratio of 1:10. The effect of pretreatment on subsequent enzymatic hydrolysis was studied at two temperatures (40 and 60 °C) and four reaction times (6, 12, 24, and 48 h). Highest glucose yield of 91 % theoretical was obtained for the DDGS pretreated at 60 °C and 24 h. The solubilized hemicellulose in the liquid fraction was further hydrolyzed with dilute H2SO4 to generate fermentable monomeric sugars. The conditions of acid hydrolysis included 1 and 4 wt% acid, 60 and 120 °C, and 0.5 and 1 h. Highest yields of xylose and arabinose were obtained at 4 wt% acid, 120 °C, and 1 h. The fermentability of the hydrolysate obtained by enzymatic hydrolysis of the SAA-pretreated DDGS was demonstrated in ethanol fermentation by Saccharomyces cerevisiae. The fermentability of the hydrolysate obtained by consecutive enzymatic and dilute acid hydrolysis was demonstrated using a succinic acid-producing microorganism, strain Escherichia coli AFP184. Under the fermentation conditions, complete utilization of glucose and arabinose was observed, whereas only 47 % of xylose was used. The succinic acid yield was 0.60 g/g total sugar consumed.

  12. Immobilization of Lipase using Alginate Hydrogel Beads and Enzymatic Evaluation in Hydrolysis of p-Nitrophenol Butyrate

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Shuang; Shang, Wenting; Yang, Xiaoxi; Zhang, Shujuan; Zhang, Xiaogang; Chen, Jiawei [Renmin Univ. of China, Beijing (China)

    2013-09-15

    The immobilization of enzyme is one of the key issues both in the field of enzymatic research and industrialization. In this work, we reported a facile method to immobilize Candida Antarctica lipase B (CALB) in alginate carrier. In the presence of calcium cation, the enzyme-alginate suspension could be cross-linked to form beads with porous structure at room temperature, and the enzyme CALB was dispersed in the beads. Activity of the enzyme-alginate composite was verified by enzymatic hydrolysis reaction of p-nitrophenol butyrate in aqueous phase. The effects of reaction parameters such as temperature, pH, embedding and lyophilized time on the reactive behavior were discussed. Reuse cycle experiments for the hydrolysis of p-nitrophenol butyrate demonstrated that activity of the enzyme-alginate composite was maintained without marked deactivation up to 6 repeated cycles.

  13. Fat content affects bioaccessibility and efficiency of enzymatic hydrolysis of lutein esters added to milk and yogurt

    OpenAIRE

    Xavier, Ana Augusta Odorissi; Mercadante, Adriana Zerlotti; Garrido-Fernández, Juan; Pérez-Gálvez, Antonio

    2014-01-01

    © 2014 Elsevier Ltd. Addition of lutein to dairy products is an alternative that widens the range of foods which could be lutein sources. However, bioaccessibility is an essential aspect to be considered during the development of products with added bioactive substances. We evaluated the in vitro bioaccessibility of lutein esters added to milk and yogurt with different fat contents, and determined the efficiency of enzymatic hydrolysis of the esters during digestion. Bioaccessibility of lutei...

  14. Enzymatic hydrolysis of rice straw and glucose fermentation using a Vertical Ball Mill Bioreactor (VBMB): Impact of operational conditions

    DEFF Research Database (Denmark)

    Castro, Rafael C.A.; Mussatto, Solange I.; Roberto, Inês C.

    ). This bioreactor was equipped with adjustable flat round plate impellers, allowing its operation with glass spheres as shear agent. For enzymatic hydrolysis, the spheres were the only variable with significant impact on the results, being achieved 87% cellulose conversion after 24 h when using the highest level...... saccharification and fermentation, in batch or fed-batch configurations, and with possibilities of operating at high solids content. Acknowledgments: FAPESP (2013/13953-6 and 2015/24813-6) and CNPq....

  15. Effects of thermo-chemical pretreatment plus microbial fermentation and enzymatic hydrolysis on saccharification and lignocellulose degradation of corn straw.

    Science.gov (United States)

    Wang, Ping; Chang, Juan; Yin, Qingqiang; Wang, Erzhu; Zhu, Qun; Song, Andong; Lu, Fushan

    2015-10-01

    In order to increase corn straw degradation, the straw was kept in the combined solution of 15% (w/w) lime supernatant and 2% (w/w) sodium hydroxide with liquid-to-solid ratio of 13:1 (mL/g) at 83.92°C for 6h; and then added with 3% (v/v) H2O2 for reaction at 50°C for 2h; finally cellulase (32.3 FPU/g dry matter) and xylanase (550 U/g dry matter) was added to keep at 50°C for 48 h. The maximal reducing sugars yield (348.77 mg/g) was increased by 126.42% (Pcellulose, hemicellulose and lignin in pretreated corn straw with enzymatic hydrolysis were increased by 40.08%, 45.71% and 52.01%, compared with the native corn straw with enzymatic hydrolysis (P<0.05). The following study indicated that the combined microbial fermentation and enzymatic hydrolysis could further increase straw degradation and reducing sugar yield (442.85 mg/g, P<0.05). Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Enhanced Enzymatic Hydrolysis and Structural Features of Corn Stover by NaOH and Ozone Combined Pretreatment

    Directory of Open Access Journals (Sweden)

    Wenhui Wang

    2018-05-01

    Full Text Available A two-step pretreatment using NaOH and ozone was performed to improve the enzymatic hydrolysis, compositions and structural characteristics of corn stover. Comparison between the unpretreated and pretreated corn stover was also made to illustrate the mechanism of the combined pretreatment. A pretreatment with 2% (w/w NaOH at 80 °C for 2 h followed by ozone treatment for 25 min with an initial pH 9 was found to be the optimal procedure and the maximum efficiency (91.73% of cellulose enzymatic hydrolysis was achieved. Furthermore, microscopic observation of changes in the surface structure of the samples showed that holes were formed and lignin and hemicellulose were partially dissolved and removed. X-ray Diffraction (XRD, Fourier Transform Infrared Spectroscopy (FTIR and Cross-Polarization Magic Angle Spinning Carbon-13 Nuclear Magnetic Resonance (CP/MAS 13C-NMR were also used to characterize the chemical structural changes after the combined pretreatment. The results were as follows: part of the cellulose I structure was destroyed and then reformed into cellulose III, the cellulose crystal indices were also changed; a wider space between the crystal layer was observed; disruption of hydrogen bonds in cellulose and disruption of ester bonds in hemicellulose; cleavage of bonds linkage in lignin-carbohydrate complexes; removal of methoxy in lignin and hemicellulose. As a result, all these changes effectively reduced recalcitrance of corn stover and promoted subsequent enzymatic hydrolysis of cellulose.

  17. Statistical optimization of recycled-paper enzymatic hydrolysis for simultaneous saccharification and fermentation via central composite design.

    Science.gov (United States)

    Liu, Qing; Cheng, Ke-ke; Zhang, Jian-an; Li, Jin-ping; Wang, Ge-hua

    2010-01-01

    A central composite design of the response surface methodology (RSM) was employed to study the effects of temperature, enzyme concentration, and stirring rate on recycled-paper enzymatic hydrolysis. Among the three variables, temperature and enzyme concentration significantly affected the conversion efficiency of substrate, whereas stirring rate was not effective. A quadratic polynomial equation was obtained for enzymatic hydrolysis by multiple regression analysis using RSM. The results of validation experiments were coincident with the predicted model. The optimum conditions for enzymatic hydrolysis were temperature, enzyme concentration, and stirring rate of 43.1 degrees C, 20 FPU g(-1) substrate, and 145 rpm, respectively. In the subsequent simultaneous saccharification and fermentation (SSF) experiment under the optimum conditions, the highest 28.7 g ethanol l(-1) was reached in the fed-batch SSF when 5% (w/v) substrate concentration was used initially, and another 5% added after 12 h fermentation. This ethanol output corresponded to 77.7% of the theoretical yield based on the glucose content in the raw material.

  18. Isolation and purification of arctigenin from Fructus Arctii by enzymatic hydrolysis combined with high-speed counter-current chromatography.

    Science.gov (United States)

    Liu, Feng; Xi, Xingjun; Wang, Mei; Fan, Li; Geng, Yanling; Wang, Xiao

    2014-02-01

    Enzymatic hydrolysis pretreatment combined with high-speed counter-current chromatography for the transformation and isolation of arctigenin from Fructus Arctii was successfully developed. In the first step, the extract solution of Fructus Arctii was enzymatic hydrolyzed by β-glucosidase. The optimal hydrolysis conditions were 40°C, pH 5.0, 24 h of hydrolysis time, and 1.25 mg/mL β-glucosidase concentration. Under these conditions, the content of arctigenin was transformed from 2.60 to 12.59 mg/g. In the second step, arctigenin in the hydrolysis products was separated and purified by high-speed counter-current chromatography with a two-phase solvent system composed of petroleum ether/ethyl acetate/methanol/water (10:25:15:20, v/v), and the fraction was analyzed by HPLC, ESI-MS, and (1)H NMR spectroscopy. Finally, 102 mg of arctigenin with a purity of 98.9% was obtained in a one-step separation from 200 mg of hydrolyzed sample. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. The pretreatment of corn stover with Gloeophyllum trabeum KU-41 for enzymatic hydrolysis

    Directory of Open Access Journals (Sweden)

    Gao Ziqing

    2012-05-01

    Full Text Available Abstract Background Pretreatment is an essential step in the enzymatic hydrolysis of biomass for bio-ethanol production. The dominant concern in this step is how to decrease the high cost of pretreatment while achieving a high sugar yield. Fungal pretreatment of biomass was previously reported to be effective, with the advantage of having a low energy requirement and requiring no application of additional chemicals. In this work, Gloeophyllum trabeum KU-41 was chosen for corn stover pretreatment through screening with 40 strains of wood-rot fungi. The objective of the current work is to find out which characteristics of corn stover pretreated with G. trabeum KU-41 determine the pretreatment method to be successful and worthwhile to apply. This will be done by determining the lignin content, structural carbohydrate, cellulose crystallinity, initial adsorption capacity of cellulase and specific surface area of pretreated corn stover. Results The content of xylan in pretreated corn stover was decreased by 43% in comparison to the untreated corn stover. The initial cellulase adsorption capacity and the specific surface area of corn stover pretreated with G. trabeum were increased by 7.0- and 2.5-fold, respectively. Also there was little increase in the cellulose crystallinity of pretreated corn stover. Conclusion G. trabeum has an efficient degradation system, and the results indicated that the conversion of cellulose to glucose increases as the accessibility of cellulose increases due to the partial removal of xylan and the structure breakage of the cell wall. This pretreatment method can be further explored as an alternative to the thermochemical pretreatment method.

  20. Total control of chromium in tanneries - thermal decomposition of filtration cake from enzymatic hydrolysis of chrome shavings.

    Science.gov (United States)

    Kocurek, P; Kolomazník, K; Bařinová, M; Hendrych, J

    2017-04-01

    This paper deals with the problem of chromium recovery from chrome-tanned waste and thus with reducing the environmental impact of the leather industry. Chrome-tanned waste was transformed by alkaline enzymatic hydrolysis promoted by magnesium oxide into practically chromium-free, commercially applicable collagen hydrolysate and filtration cake containing a high portion of chromium. The crude and magnesium-deprived chromium cakes were subjected to a process of thermal decomposition at 650°C under oxygen-free conditions to reduce the amount of this waste and to study the effect of magnesium removal on the resulting products. Oxygen-free conditions were applied in order to prevent the oxidation of trivalent chromium into the hazardous hexavalent form. Thermal decomposition products from both crude and magnesium-deprived chrome cakes were characterized by high chromium content over 50%, which occurred as eskolaite (Cr 2 O 3 ) and magnesiochromite (MgCr 2 O 4 ) crystal phases, respectively. Thermal decomposition decreased the amount of chrome cake dry feed by 90%. Based on the performed experiments, a scheme for the total control of chromium in the leather industry was designed.

  1. Combination of Superheated Steam with Laccase Pretreatment Together with Size Reduction to Enhance Enzymatic Hydrolysis of Oil Palm Biomass

    Directory of Open Access Journals (Sweden)

    Nur Fatin Athirah Ahmad Rizal

    2018-04-01

    Full Text Available The combination of superheated steam (SHS with ligninolytic enzyme laccase pretreatment together with size reduction was conducted in order to enhance the enzymatic hydrolysis of oil palm biomass into glucose. The oil palm empty fruit bunch (OPEFB and oil palm mesocarp fiber (OPMF were pretreated with SHS and ground using a hammer mill to sizes of 2, 1, 0.5 and 0.25 mm before pretreatment using laccase to remove lignin. This study showed that reduction of size from raw to 0.25 mm plays important role in lignin degradation by laccase that removed 38.7% and 39.6% of the lignin from OPEFB and OPMF, respectively. The subsequent saccharification process of these pretreated OPEFB and OPMF generates glucose yields of 71.5% and 63.0%, which represent a 4.6 and 4.8-fold increase, respectively, as compared to untreated samples. This study showed that the combination of SHS with laccase pretreatment together with size reduction could enhance the glucose yield.

  2. A mathematical model for the effects of volume fraction and fiber aspect ratio of biomass mixture during enzymatic hydrolysis

    Science.gov (United States)

    Jamil, Norazaliza Mohd; Wang, Qi

    2017-09-01

    Renewable energy or biofuel from lignocellulosic biomass is an alternative way to replace the depleting fossil fuels. The production cost can be reduced by increasing the concentration of biomass particles. However, lignocellulosic biomass is a suspension of natural fibres, and processing at high solid concentration is a challenging task. Thus, understanding the factors that affect the rheology of biomass suspension is crucial in order to maximize the production at a minimum cost. Our aim was to develop a mathematical model for enzymatic hydrolysis of cellulose by combining three scales: the macroscopic flow field, the mesoscopic particle orientation, and the microscopic reactive kinetics. The governing equations for the flow field, particle stress, kinetic equations, and particle orientation were coupled and were simultaneously solved using a finite element method based software, COMSOL. One of the main results was the changes in rheology of biomass suspension were not only due to the decrease in volume fraction of particles, but also due the types of fibres. The results from the simulation model agreed qualitatively with the experimental findings. This approach has enables us to obtain better predictive capabilities, hence increasing our understanding on the behaviour of biomass suspension.

  3. Enzymatic Hydrolysis of Mannan from Konjac (Amorphophallus sp. Using Mannanase from Streptomyces lipmanii to Produce Manno-oligosaccharides

    Directory of Open Access Journals (Sweden)

    Ashadi Sasongko

    2015-09-01

    Full Text Available Mannan is an abundant polysaccharide that can be found in konjac (Amorphophallus sp.. Mannan can be enzymatically hydrolyzed using mannanase to produce manno-oligosaccharides which can be used as a prebiotic. The aims of this research are to determine the production time of mannanase from Streptomyces lipmanii, perform enzyme characterization, optimize the hydrolysis time, and characterize the hydrolysis product. A qualitative assay using the indicator Congo red showed that S. lipmanii generated a clear zone, indicating that S. lipmanii produced mannanase in konjac medium and possessed mannanolytic activity. Enzyme activity was determined through reducing sugar measurement using the dinitrosalycylic acid method, and optimum enzyme production was achieved at the second day of culture. Characterization of the enzyme showed that hydrolysis was optimum at pH 7 and at a temperature of 50 oC. The reducing sugar content was increased by an increasing the hydrolysis time, and reached an optimum time at 2 h. The degree of polymerization value of three was achieved after 2 h hydrolysis of mannan from konjac, indicating the formation of oligosaccharides. Analysis by thin layer chromatography using butanol, acetic acid, and water in a ratio of 2:1:1 as eluent showed the presence of compounds with a retention time between those of mannose and mannotetrose. Confirmation was also performed by HPLC, based on the retention time

  4. Development of an ultrahigh-temperature process for the enzymatic hydrolysis of lactose. IV. Immobilization of two thermostable beta-glycosidases and optimization of a packed-bed reactor for lactose conversion.

    Science.gov (United States)

    Petzelbauer, Inge; Kuhn, Bernhard; Splechtna, Barbara; Kulbe, Klaus D; Nidetzky, Bernd

    2002-03-20

    Recombinant hyperthermostable beta-glycosidases from the archaea Sulfolobus solfataricus (Ss beta Gly) and Pyrococcus furiosus (CelB) were covalently attached onto the insoluble carriers chitosan, controlled pore glass (CPG), and Eupergit C. For each enzyme/carrier pair, the protein-binding capacity, the immobilization yield, the pH profiles for activity and stability, the activity/temperature profile, and the kinetic constants for lactose hydrolysis at 70 degrees C were determined. Eupergit C was best among the carriers in regard to retention of native-like activity and stability of Ss beta Gly and CelB over the pH range 3.0-7.5. Its protein binding capacity of approximately 0.003 (on a mass basis) was one-third times that of CPG, while immobilization yields were typically 80% in each case. Activation energies for lactose conversion by the immobilized enzymes at pH 5.5 were in the range 50-60 kJ/mol. This is compared to values of approximately 75 kJ/mol for the free enzymes. Immobilization expands the useful pH range for CelB and Ss beta Gly by approximately 1.5 pH units toward pH 3.5 and pH 4.5, respectively. A packed-bed enzyme reactor was developed for the continuous conversion of lactose in different media, including whey and milk, and operated over extended reaction times of up to 14 days. The productivities of the Eupergit C-immobilized enzyme reactor were determined at dilution rates between 1 and 12 h(-1), and using 45 and 170 g/L initial lactose. Results of kinetic modeling for the same reactor, assuming plug flow and steady state, suggest the presence of mass-transfer limitation of the reaction rate under the conditions used. Formation of galacto-oligosaccharides in the continuous packed-bed reactor and in the batch reactor using free enzyme was closely similar in regard to yield and individual saccharide components produced. Copyright 2002 John Wiley & Sons, Inc. Biotechnol Bioeng 77: 619-631, 2002; DOI 10.1002/bit.10110

  5. Molecular characterization and enzymatic hydrolysis of naringin extracted from kinnow peel waste.

    Science.gov (United States)

    Puri, Munish; Kaur, Aneet; Schwarz, Wolfgang H; Singh, Satbir; Kennedy, J F

    2011-01-01

    Kinnow peel, a waste rich in glycosylated phenolic substances, is the principal by-product of the citrus fruit processing industry and its disposal is becoming a major problem. This peel is rich in naringin and may be used for rhamnose production by utilizing α-L-rhamnosidase (EC 3.2.1.40), an enzyme that catalyzes the cleavage of terminal rhamnosyl groups from naringin to yield prunin and rhamnose. In this work, infrared (IR) spectroscopy confirmed molecular characteristics of naringin extracted from kinnow peel waste. Further, recombinant α-L-rhamnosidase purified from Escherichia coli cells using immobilized metal-chelate affinity chromatography (IMAC) was used for naringin hydrolysis. The purified enzyme was inhibited by Hg2+ (1 mM), 4-hydroxymercuribenzoate (0.1 mM) and cyanamide (0.1 mM). The purified enzyme established hydrolysis of naringin extracted from kinnow peel and thus endorses its industrial applicability for producing rhamnose. Copyright © 2010 Elsevier B.V. All rights reserved.

  6. Anti-Inflammatory and Antioxidant Properties of Peptides Released from β-Lactoglobulin by High Hydrostatic Pressure-Assisted Enzymatic Hydrolysis.

    Science.gov (United States)

    Bamdad, Fatemeh; Bark, Seonghee; Kwon, Chul Hee; Suh, Joo-Won; Sunwoo, Hoon

    2017-06-07

    β-lactoglobulin hydrolysates (BLGH) have shown antioxidant, antihypertensive, antimicrobial, and opioid activity. In the current study, an innovative combination of high hydrostatic pressure and enzymatic hydrolysis (HHP-EH) was used to increase the yield of short bioactive peptides, and evaluate the anti-inflammatory and antioxidant properties of the BLGH produced by the HHP-EH process. BLG was enzymatically hydrolyzed by different proteases at an enzyme-to-substrate ratio of 1:100 under HHP (100 MPa) and compared with hydrolysates obtained under atmospheric pressure (AP-EH at 0.1 MPa). The degree of hydrolysis (DH), molecular weight distribution, and the antioxidant and anti-inflammatory properties of hydrolysates in chemical and cellular models were evaluated. BLGH obtained under HHP-EH showed higher DH than the hydrolysates obtained under AP-EH. Free radical scavenging and the reducing capacity were also significantly stronger in HHP-BLGH compared to AP-BLGH. The BLGH produced by alcalase (Alc) (BLG-Alc) showed significantly higher antioxidant properties among the six enzymes examined in this study. The anti-inflammatory properties of BLG-HHP-Alc were observed in lipopolysaccharide-stimulated macrophage cells by a lower level of nitric oxide production and the suppression of the synthesis of pro-inflammatory cytokines. Peptide sequencing revealed that 38% of the amino acids in BLG-HHP-Alc are hydrophobic and aromatic residues, which contribute to its anti-inflammatory properties. Enzymatic hydrolysis of BLG under HHP produces a higher yield of short bioactive peptides with potential antioxidant and anti-inflammatory effects.

  7. Use of Sugarcane Bagasse with Different Particle Sizes to Determine the Relationship between Physical Properties and Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Jingbo Li

    2016-04-01

    Full Text Available The supramolecular structures of a substrate, such as crystallinity, specific surface area, average pore size, and cellulase adsorption capacity, etc., affect the enzymatic hydrolysis of a lignocellulosic biomass. It is unclear which of these factors is most important for efficient hydrolysis. To eliminate the influence of the hemicellulose content and the lignin, sugarcane bagasse samples with the same cellulose, hemicellulose, and lignin content but with different particle sizes were used as substrates to investigate the relationship between physical properties and enzymatic conversion efficiency. When the content of hemicellulose and lignin was not significantly different, the decrease in the crystallinity index (CrI and the increase in the specific surface area (SSA, cellulase adsorption, average pore size, and the cellulase adsorption per SSA could give rise to higher enzymatic convertibility. The effects of the CrI and the average pore size were more pronounced than the effects of the SSA, the cellulase adsorption capacity, and the cellulase adsorption per SSA. According to the developed formula, the CrI was more influential than the average pore size under the specific conditions.

  8. Enzymatic hydrolysis on protein and β-glucan content of Sang-yodrice bran hydrolysatesand their anti-inflammatory activityonRAW 264.7 cells

    Directory of Open Access Journals (Sweden)

    Natcha Phantuwong

    2017-12-01

    Full Text Available Background: Research focusing on the improvement of the utilization of rice bran is increasing due to its nutritional properties. Several biological activities of rice bran hydrolysates and its constituents have been reported. Sang-yod rice, a local rice variety in Southern of Thailand, is a pigmented rice. Furthermore, its bran has high nutritive value and health beneficial components. Accordingly, there is growing interest in transforming this by-product into a functional food ingredient. Objective: To investigate the effect of enzymatic hydrolysis processes on the digestion of protein and β-glucan and evaluate anti-proinflammatory properties of selected hydrolysates on RAW 264.7 macrophage cells. Method: Sang-yod rice bran hydrolysates were obtained using a single or co-enzymatic hydrolysis process and sequential hydrolysis process using amyloglucosidase and protease G6. Effects of enzyme concentration (3-5% v/w and hydrolysis duration (30, 60, and 120 min on soluble protein and β-glucan contents of obtained rice bran hydrolysates were evaluated. The selected rice bran hydrolysates were evaluated for their cell viability and inhibition against NO and pro-inflammatory cytokines generation on RAW 264.7 mouse macrophage cell lines. Results: Protein content (0.59-3.37 % of the rice bran hydrolysates (RBHs was increased by increasing of enzyme concentration (3-5% v/w and hydrolysis time (60-120 min. However, the β-glucan content (0.88-4.63% of RBHs decreased with the increase of those parameters. The RBHs derived by the sequential process using 5% v/w enzyme concentration and 60 min hydrolysis time gave high protein (3.23% and high β-glucan (4.02% contents. The hydrolysates with high amount of protein and/or β-glucan contents demonstrated no cytotoxicity against RAW 264.7 cells at concentration range of 100-2,000 μg/ml. Additionally, they demonstrated NO inhibition and pro-inflammatory inhibition ranges of 49.09-71.63% and 9

  9. Electrospray ionization mass spectrometry for the hydrolysis complexes of cisplatin : Implications for the hydrolysis process of platinum complexes

    NARCIS (Netherlands)

    Xie, Feifan; Colin, Pieter; Van Bocxlaer, Jan

    Non-enzyme-dependent hydrolysis of the drug cisplatin is important for its mode of action and toxicity. However, up until today, the hydrolysis process of cisplatin is still not completely understood. In the present study, the hydrolysis of cisplatin in an aqueous solution was systematically

  10. Non-ionic Surfactants and Non-Catalytic Protein Treatment on Enzymatic Hydrolysis of Pretreated Creeping Wild Ryegrass

    Science.gov (United States)

    Zheng, Yi; Pan, Zhongli; Zhang, Ruihong; Wang, Donghai; Jenkins, Bryan

    Our previous research has shown that saline Creeping Wild Ryegrass (CWR), Leymus triticoides, has a great potential to be used for bioethanol production because of its high fermentable sugar yield, up to 85% cellulose conversion of pretreated CWR. However, the high cost of enzyme is still one of the obstacles making large-scale lignocellulosic bioethanol production economically difficult. It is desirable to use reduced enzyme loading to produce fermentable sugars with high yield and low cost. To reduce the enzyme loading, the effect of addition of non-ionic surfactants and non-catalytic protein on the enzymatic hydrolysis of pretreated CWR was investigated in this study. Tween 20, Tween 80, and bovine serum albumin (BSA) were used as additives to improve the enzymatic hydrolysis of dilute sulfuric-acid-pretreated CWR. Under the loading of 0.1 g additives/g dry solid, Tween 20 was the most effective additive, followed by Tween 80 and BSA. With the addition of Tween 20 mixed with cellulase loading of 15 FPU/g cellulose, the cellulose conversion increased 14% (from 75 to 89%), which was similar to that with cellulase loading of 30 FPU/g cellulose and without additive addition. The results of cellulase and BSA adsorption on the Avicel PH101, pretreated CWR, and lignaceous residue of pretreated CWR support the theory that the primary mechanism behind the additives is prevention of non-productive adsorption of enzymes on lignaceous material of pretreated CWR. The addition of additives could be a promising technology to improve the enzymatic hydrolysis by reducing the enzyme activity loss caused by non-productive adsorption.

  11. Evaluation of soluble fraction and enzymatic residual fraction of dilute dry acid, ethylenediamine, and steam explosion pretreated corn stover on the enzymatic hydrolysis of cellulose.

    Science.gov (United States)

    Qin, Lei; Liu, Li; Li, Wen-Chao; Zhu, Jia-Qing; Li, Bing-Zhi; Yuan, Ying-Jin

    2016-06-01

    This study is aimed to examine the inhibition of soluble fraction (SF) and enzymatic residual fraction (ERF) in dry dilute acid (DDA), ethylenediamine (EDA) and steam explosion (SE) pretreated corn stover (CS) on the enzymatic digestibility of cellulose. SF of DDA, EDA and SE pretreated CS has high xylose, soluble lignin and xylo-oligomer content, respectively. SF of EDA pretreated CS leads to the highest inhibition, followed by SE and DDA pretreated CS. Inhibition of ERF of DDA and SE pretreated CS is higher than that of EDA pretreated CS. The inhibition degree (A0/A) of SF is 1.76 and 1.21 times to that of ERF for EDA and SE pretreated CS, respectively. The inhibition degree of ERF is 1.05 times to that of SF in DDA pretreated CS. The quantitative analysis shows that SF of EDA pretreated CS, SF and ERF of SE pretreated CS cause significant inhibition during enzymatic hydrolysis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Optimization of Saccharification Conditions of Lignocellulosic Biomass under Alkaline Pre-Treatment and Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Rafał Łukajtis

    2018-04-01

    Full Text Available Pre-treatment is a significant step in the production of second-generation biofuels from waste lignocellulosic materials. Obtaining biofuels as a result of fermentation processes requires appropriate pre-treatment conditions ensuring the highest possible degree of saccharification of the feed material. An influence of the following process parameters were investigated for alkaline pre-treatment of Salix viminalis L.: catalyst concentration (NaOH, temperature, pre-treatment time and granulation. For this purpose, experiments were carried out in accordance to the Box-Behnken design for four factors. In the saccharification process of the pre-treated biomass, cellulolytic enzymes immobilized on diatomaceous earth were used. Based on the obtained results, a mathematical model for the optimal conditions of alkaline pre-treatment prediction is proposed. The optimal conditions of alkaline pre-treatment are established as follows: granulation 0.75 mm, catalyst concentration 7%, pre-treatment time 6 h and temperature 65 °C if the saccharification efficiency and cost analysis are considered. An influence of the optimized pre-treatment on both the chemical composition and structural changes for six various lignocellulosic materials (energetic willow, energetic poplar, beech, triticale, meadow grass, corncobs was investigated. SEM images of raw and pre-treated biomass samples are included in order to follow the changes in the biomass structure during hydrolysis.

  13. Enhanced enzymatic hydrolysis and acetone-butanol-ethanol fermentation of sugarcane bagasse by combined diluted acid with oxidate ammonolysis pretreatment.

    Science.gov (United States)

    Li, Hailong; Xiong, Lian; Chen, Xuefang; Wang, Can; Qi, Gaoxiang; Huang, Chao; Luo, Mutan; Chen, Xinde

    2017-03-01

    This study aims to propose a biorefinery pretreatment technology for the bioconversion of sugarcane bagasse (SB) into biofuels and N-fertilizers. Performance of diluted acid (DA), aqueous ammonia (AA), oxidate ammonolysis (OA) and the combined DA with AA or OA were compared in SB pretreatment by enzymatic hydrolysis, structural characterization and acetone-butanol-ethanol (ABE) fermentation. Results indicated that DA-OA pretreatment improves the digestibility of SB by sufficiently hydrolyzing hemicellulose into fermentable monosaccharides and oxidating lignin into soluble N-fertilizer with high nitrogen content (11.25%) and low C/N ratio (3.39). The enzymatic hydrolysates from DA-OA pretreated SB mainly composed of glucose was more suitable for the production of ABE solvents than the enzymatic hydrolysates from OA pretreated SB containing high ratio of xylose. The fermentation of enzymatic hydrolysates from DA-OA pretreated SB produced 12.12g/L ABE in 120h. These results suggested that SB could be utilized efficient, economic, and environmental by DA-OA pretreatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Evaluation of jumbo squid (Dosidicus gigas byproduct hydrolysates obtained by acid-enzymatic hydrolysis and by autohydrolysis in practical diets for Pacific white shrimp (Litopenaeus vannamei

    Directory of Open Access Journals (Sweden)

    Mayra Lizett González-Félix

    2014-09-01

    Full Text Available The marine bioprocessing industry offers great potential to utilize byproducts for fish meal replacement in aquafeeds. Jumbo squid is an important fishery commodity in Mexico, but only the mantle is marketed. Head, fins, guts and tentacles are discarded in spite of being protein-rich byproducts. This study evaluated the use of two jumbo squid byproduct hydrolysates obtained by acid-enzymatic hydrolysis (AEH and by autohydrolysis (AH as ingredients in practical diets for shrimp. The hydrolysates were included at levels of 2.5 and 5.0% of the diet dry weight in four practical diets, including a control diet without hydrolysate. Shrimp growth and survival were not significantly affected by the dietary treatments. Postharvest quality of abdominal muscle was evaluated in terms of proximate composition and sensory evaluation. Significantly higher crude protein was observed in the muscle of shrimp fed the highest hydrolysate levels, AH 5% (204.8 g kg- 1 or AEH 5% (201.3 g kg- 1. Sensory analysis of cooked muscle showed significant differences for all variables evaluated: color, odor, flavor, and firmness. It was concluded that Jumbo squid byproducts can be successfully processed by autohydrolysis or acid-enzymatic hydrolysis, and that up to 5.0% of the hydrolysates can be incorporated into shrimp diets without affecting growth or survival.

  15. Ethanol production from sugars obtained during enzymatic hydrolysis of elephant grass (Pennisetum purpureum, Schum.) pretreated by steam explosion.

    Science.gov (United States)

    Scholl, Angélica Luisi; Menegol, Daiane; Pitarelo, Ana Paula; Fontana, Roselei Claudete; Zandoná Filho, Arion; Ramos, Luiz Pereira; Dillon, Aldo José Pinheiro; Camassola, Marli

    2015-09-01

    In this work, steam explosion was used a pretreatment method to improve the conversion of elephant grass (Pennisetum purpureum) to cellulosic ethanol. This way, enzymatic hydrolysis of vaccum-drained and water-washed steam-treated substrates was carried out with Penicillium echinulatum enzymes while Saccharomyces cerevisiae CAT-1 was used for fermentation. After 48 h of hydrolysis, the highest yield of reducing sugars was obtained from vaccum-drained steam-treated substrates that were produced after 10 min at 200 °C (863.42 ± 62.52 mg/g). However, the highest glucose yield was derived from water-washed steam-treated substrates that were produced after 10 min at 190 °C (248.34 ± 6.27 mg/g) and 200 °C (246.00 ± 9.60 mg/g). Nevertheless, the highest ethanol production was obtained from water-washed steam-treated substrates that were produced after 6 min at 200 °C. These data revealed that water washing is a critical step for ethanol production from steam-treated elephant grass and that pretreatment generates a great deal of water soluble inhibitory compounds for hydrolysis and fermentation, which were partly characterized as part of this study. Copyright © 2015 Elsevier Ltd. All rights reserved.

  16. Enzymatic hydrolysis of pretreated Alfa fibers (Stipa tenacissima) using β-d-glucosidase and xylanase of Talaromyces thermophilus from solid-state fermentation.

    Science.gov (United States)

    Mallek-Fakhfakh, Hanen; Fakhfakh, Jawhar; Walha, Kamel; Hassairi, Hajer; Gargouri, Ali; Belghith, Hafedh

    2017-10-01

    This work aims at realizing an optimal hydrolysis of pretreated Alfa fibers (Stipa tenacissima) through the use of enzymes produced from Talaromyces thermophilus AX4, namely β-d-glucosidase and xylanase, by a solid state fermentation process of an agro-industrial waste (wheat bran supplemented with lactose). The carbon source was firstly selected and the optimal values of three other parameters were determined: substrate loading (10g), moisture content (85%) and production time (10days); which led to an optimized enzymatic juice. The outcome was then supplemented with cellulases of T. reesei and used to optimize the enzymatic saccharification of alkali-pretreated Alfa fibers (PAF). The maximum saccharification yield of 83.23% was achieved under optimized conditions (substrate concentration 3.7% (w/v), time 144h and enzyme loading of 0.8 FPU, 15U CMCase, 60U β-d-glucosidase and 125U xylanase).The structural modification of PAF due to enzymatic saccharification was supported by the changes of morphologic and chemical composition observed through macroscopic representation, FTIR and X-Ray analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Two-Step Hot-Compressed Water Treatment of Douglas Fir for Efficient Total Sugar Recovery by Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    Hiroyuki Inoue

    2016-04-01

    Full Text Available The non-catalytic hydrothermal pretreatment of softwood is generally less effective for subsequent enzymatic hydrolysis. In this study, the efficacy of hot-compressed water (HCW treatment of Douglas fir was investigated between 180 °C and 260 °C, allowing solubilization of the cellulose components. The enzymatic digestibility of cellulosic residues increased significantly under HCW conditions > 250 °C, and the enhanced glucan digestibility was closely related to the decomposition of the cellulose component. Combination of the first-stage HCW treatment (220 °C, 5 min to recover hemicellulosic sugars with the second-stage HCW treatment (260 °C, 5 min to improve cellulose digestibility gave a total sugar recovery of 56.2% based on the dried raw materials. This yield was 1.4 times higher than that from the one-step HCW-treated sample (260 °C, 5 min. Additionally, an enzymatic hydrolysate from the two-step HCW-treated sample exceeded 90% of the ethanol fermentation yield based on the total sugars present in the hydrolysates. These results suggest the potential of the two-step HCW treatment of softwood as a pretreatment technology for efficient total sugar recovery and ethanol production.

  18. Base hydrolysis and hydrothermal processing of PBX-9404

    International Nuclear Information System (INIS)

    Flesner, R.L.; Spontarelli, T.; Dell'Orco, P.C.; Sanchez, J.A.

    1994-01-01

    Base hydrolysis in combination with hydrothermal processing has been proposed as an environmentally acceptable alternative to open burning/open detonation for degradation and destruction of high explosives. In this report, the authors examine gaseous and aqueous products of base hydrolysis of the HMX-based plastic bonded explosive, PBX-9404. They also examined products from the subsequent hydrothermal treatment of the base hydrolysate. The gases produced from hydrolysis of PBX-9404 are ammonia, nitrous oxide, and nitrogen. Major aqueous products are sodium formate, acetate, nitrate, and nitrite, but not all carbon products have been identified. Hydrothermal processing of base hydrolysate destroyed up to 98% of the organic carbon in solution, and higher destruction efficiencies are possible. Major gas products detected from hydrothermal processing were nitrogen and nitrous oxide

  19. An integrated model for the technical and economic evaluation of an enzymatic biomass conversion process

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, Q A; Saddler, J N [Forintek Canada Corp., Ottawa, Ontario (CA). Dept. of Biotechnology and Chemistry

    1991-01-01

    A process simulation model was constructed, using the Lotus 123 spreadsheet, to evaluate the technical and economic feasibility of a lignocellulosic-to-ethanol bioconversion process. The major components of the process were: steam pretreatment, fractionation, enzyme production, enzymatic hydrolysis, ethanol fermentation of glucose and xylose, product recovery, and waste treatment. The model provided an estimation of the price of ethanol and evaluated the interdependence of process parameters and their effect on the production cost of ethanol. A case study of a plant processing 500 tonnes of aspenwood per day showed that the parameters which had the most significant impact on the price of ethanol were: the cost of wood, cost of enzymes, efficiency of cellulose hydrolysis, ethanol yield from xylose, efficiency of the fractionation process, and the selling price of the lignin by-product. (author).

  20. Pretreatment of flaxseed protein isolate by high hydrostatic pressure: Impacts on protein structure, enzymatic hydrolysis and final hydrolysate antioxidant capacities.

    Science.gov (United States)

    Perreault, Véronique; Hénaux, Loïc; Bazinet, Laurent; Doyen, Alain

    2017-04-15

    The effect of high hydrostatic pressure (HHP) on flaxseed protein structure and peptide profiles, obtained after protein hydrolysis, was investigated. Isolated flaxseed protein (1%, m/v) was subjected to HHP (600MPa, 5min or 20min at 20°C) prior to hydrolysis with trypsin only and trypsin-pronase. The results demonstrated that HHP treatment induced dissociation of flaxseed proteins and generated higher molecular weight aggregates as a function of processing duration. Fluorescence spectroscopy showed that HHP treatment, as well as processing duration, had an impact on flaxseed protein structure since exposition of hydrophobic amino acid tyrosine was modified. Except for some specific peptides, the concentrations of which were modified, similar peptide profiles were obtained after hydrolysis of pressure-treated proteins using trypsin. Finally, hydrolysates obtained using trypsin-pronase had a greater antioxidant capacity (ORAC) than control samples; these results confirmed that HHP enhanced the generation of antioxidant peptides. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Accessibility of Enzymatically Delignified Bambusa bambos for Efficient Hydrolysis at Minimum Cellulase Loading: An Optimization Study.

    Science.gov (United States)

    Kuila, Arindam; Mukhopadhyay, Mainak; Tuli, D K; Banerjee, Rintu

    2011-01-01

    In the present investigation, Bambusa bambos was used for optimization of enzymatic pretreatment and saccharification. Maximum enzymatic delignification achieved was 84%, after 8 h of incubation time. Highest reducing sugar yield from enzyme-pretreated Bambusa bambos was 818.01 mg/g dry substrate after 8 h of incubation time at a low cellulase loading (endoglucanase, β-glucosidase, exoglucanase, and xylanase were 1.63 IU/mL, 1.28 IU/mL, 0.08 IU/mL, and 47.93 IU/mL, respectively). Enzyme-treated substrate of Bambusa bambos was characterized by analytical techniques such as Fourier transformed infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM). The FTIR spectrum showed that the absorption peaks of several functional groups were decreased after enzymatic pretreatment. XRD analysis indicated that cellulose crystallinity of enzyme-treated samples was increased due to the removal of amorphous lignin and hemicelluloses. SEM image showed that surface structure of Bambusa bambos was distorted after enzymatic pretreatment.

  2. Accessibility of Enzymatically Delignified Bambusa bambos for Efficient Hydrolysis at Minimum Cellulase Loading: An Optimization Study

    Directory of Open Access Journals (Sweden)

    Arindam Kuila

    2011-01-01

    Full Text Available In the present investigation, Bambusa bambos was used for optimization of enzymatic pretreatment and saccharification. Maximum enzymatic delignification achieved was 84%, after 8 h of incubation time. Highest reducing sugar yield from enzyme-pretreated Bambusa bambos was 818.01 mg/g dry substrate after 8 h of incubation time at a low cellulase loading (endoglucanase, β-glucosidase, exoglucanase, and xylanase were 1.63 IU/mL, 1.28 IU/mL, 0.08 IU/mL, and 47.93 IU/mL, respectively. Enzyme-treated substrate of Bambusa bambos was characterized by analytical techniques such as Fourier transformed infrared spectroscopy (FTIR, X-ray diffraction (XRD, and scanning electron microscopy (SEM. The FTIR spectrum showed that the absorption peaks of several functional groups were decreased after enzymatic pretreatment. XRD analysis indicated that cellulose crystallinity of enzyme-treated samples was increased due to the removal of amorphous lignin and hemicelluloses. SEM image showed that surface structure of Bambusa bambos was distorted after enzymatic pretreatment.

  3. Obtaining nanofibers from curauá and sugarcane bagasse fibers using enzymatic hydrolysis followed by sonication

    DEFF Research Database (Denmark)

    Campos, Adriana de; Correa, Ana Carolina; Cannella, David

    2013-01-01

    This paper is an initial study of the implementation of two new enzymes, an endoglucanase and a concoction of hemicellulases and pectinases to obtain cellulosic nanoparticles. In this study, curauá and sugarcane bagasse were dewaxed and bleached prior to enzymatic action for 72 h at 50 °C, and th...

  4. Enzymatic hydrolysis of wood. III. Pretreatment of woods with acidic methanol-water mixture

    Energy Technology Data Exchange (ETDEWEB)

    Shimizu, K; Usami, K

    1980-01-01

    Wood meal of Pinus densiflora (I) and Fagus crenata (II) was heated in aqueous methanol containing 0.1-0.6% HCl for 15-90 minutes at 120-170 degrees Centigrade to remove lignin and hydrolyse hemicelluloses. About 75% of the lignin could be removed from (I) and 90% from (II) under appropriate conditions. The cellulosic residues were hydrolysed with Trichoderma viride; it was necessary to remove more than 70% of the lignin from (I) and 80% from (II) for complete hydrolysis of the cellulose. Lignin was precipitated from the hydrolysis liquor by distilling off the methanol. The effects of composition of the MeOH-H/sub 2/O mixture, temperature, reaction time and HC1 concentration were studied.

  5. STRUCTURAL CHANGES EVIDENCED BY FTIR SPECTROSCOPY IN CELLULOSE MATERIALS AFTER PRE-TREATMENT WITH IONIC LIQUID AND ENZYMATIC HYDROLYSIS

    Directory of Open Access Journals (Sweden)

    Iuliana Spiridon

    2011-02-01

    Full Text Available Attempts were made to enhance the hydrolysis of Asclepias syriaca (As seed floss and poplar seed floss (PSF by cellulase after pre-treatment with ionic liquids. Two ionic liquids, namely 1-butyl-3-methylimidazolium chloride [BMIM]Cl and 1-ethyl-3-methylimidazolium tetrachloroaluminate [EMIM]Cl-AlCl3, were used. In comparison with conventional cellulose pretreatment processes, the ionic liquids were used under a milder condition corresponding to the optimum activity of cellulase. Hydrolysis kinetics of the IL-treated cellulose materials was significantly enhanced. The initial hydrolysis rates for IL-treated cellulose materials were greater than those of non-treated ones. The structural modifications of hydrolyzed cellulose materials were analyzed using FTIR spectroscopy.

  6. Management of Purex spent solvents by the alkaline hydrolysis process

    International Nuclear Information System (INIS)

    Srinivas, C.; Manohar, Smitha; Vincent, Tessy; Wattal, P.K.; Theyyunni, T.K.

    1995-01-01

    Various treatment processes were evaluated on a laboratory scale for the management of the spent solvent from the extraction of nuclear materials. Based on the lab scale evaluation it is proposed to adopt the alkaline hydrolysis process as the treatment mode for the spent solvent. The process has advantages over the other processes in terms of simplicity, low cost and ease of disposal of the secondary waste generated. (author)

  7. Detoxification of acid pretreated spruce hydrolysates with ferrous sulfate and hydrogen peroxide improves enzymatic hydrolysis and fermentation.

    Science.gov (United States)

    Soudham, Venkata Prabhakar; Brandberg, Tomas; Mikkola, Jyri-Pekka; Larsson, Christer

    2014-08-01

    The aim of the present work was to investigate whether a detoxification method already in use during waste water treatment could be functional also for ethanol production based on lignocellulosic substrates. Chemical conditioning of spruce hydrolysate with hydrogen peroxide (H₂O₂) and ferrous sulfate (FeSO₄) was shown to be an efficient strategy to remove significant amounts of inhibitory compounds and, simultaneously, to enhance the enzymatic hydrolysis and fermentability of the substrates. Without treatment, the hydrolysates were hardly fermentable with maximum ethanol concentration below 0.4 g/l. In contrast, treatment by 2.5 mM FeSO₄ and 150 mM H₂O₂ yielded a maximum ethanol concentration of 8.3 g/l. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Eco-friendly dry chemo-mechanical pretreatments of lignocellulosic biomass: Impact on energy and yield of the enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Barakat, Abdellatif; Chuetor, Santi; Monlau, Florian; Solhy, Abderrahim; Rouau, Xavier

    2014-01-01

    Highlights: • Innovative dry NaOH chemo-mechanical pretreatment was developed. • Dry (TS dry ) and dilute (TS dilute ) NaOH chemo-mechanical pretreatment were compared. • TS dilute consumed higher amounts of water and energy compared to TS dry . • Energy efficiency obtained for TS dilute was 0.417 kg glucose kW h −1 and 0.888 for TS dry . - Abstract: In this study, we developed an eco-friendly dry alkaline chemomechanical pretreatment of wheat straw without production of waste and liquid fractions with objective to save energy input, to decrease the environmental impact and to increase enzymatic hydrolysis. Wheat straw was pretreated with NH 3 , NaOH-H 2 O 2 , NH 3 -H 2 O 2 and NaOH at high materials concentration (5 kg/L) equivalent to biomass/liquid ratio of 1/5 (dry chemomechanical) and at low materials concentration (0.2 kg/L) equivalent to biomass/liquid ratio of 5/1 (dilute chemomechanical). Untreated and chemical treated wheat straw samples were subjected to grinding and milling following by enzymatic hydrolysis with commercial cellulases. NaOH and NaOH-H 2 O 2 dry chemomechanical pretreatments were found to be more effective in decreasing the particle size and energy consumption and increasing the surface area. However, alkaline dilute-chemomechanical treatments consumed higher amounts of water (5 L water/1 kg biomass) and energy compared to dry-chemomechanical treatments. In point of fact, the lowest energy efficiency obtained was 0.417 kg glucose kW h −1 for dilute-chemomechanical treatments compared to 0.888 kg glucose kW h −1 glucose kW h −1 for dry-chemomechanical treatments. Alkaline dry-chemomechanical pretreatments approach appears more attractive and efficient in terms of glucose, energy efficiency and environmental impact, compared to conventional alkaline chemomechanical pretreatments

  9. Radioactive demonstration of the ''late wash'' Precipitate Hydrolysis Process

    International Nuclear Information System (INIS)

    Bibler, N.E.; Ferrara, D.M.; Ha, B.C.

    1992-01-01

    This report presents results of the radioactive demonstration of the DWPF Precipitate Hydrolysis Process as it would occur in the ''late wash'' flowsheet in the absence of hydroxylamine nitrate. Radioactive precipitate containing Cs-137 from the April, 1983, in-tank precipitation demonstration in Tank 48 was used for these tests

  10. Testing of alkaline and enzymatic hydrolysis pretreatments for fat particles in slaughterhouse wastewater.

    Science.gov (United States)

    Masse, L; Kennedy, K J; Chou, S

    2001-04-01

    Four pretreatments to hydrolyse and/or reduce the size of fat particles in slaughterhouse wastewater (SHW) were tested: sodium hydroxide and three lipases of plant, bacterial and animal (pancreatic) origin. Hydrolysing agents and SHW containing between 2.5 and 3 g/l of fat particles were mixed at room temperature for 4 h. Additions of 5-400 meq NaOH/l did not increase soluble COD (SCOD) in SHW, but the average particle size was reduced to 73% +/- 7% of the initial average particle size (D(in)) at NaOH concentrations ranging from 150 to 300 meq/l. Pretreatment with pancreatic lipase PL-250 reduced the average particle size to a maximum of 60% +/- 3% of D(in). As D(in) was decreased from 359 to 68 microns, the enzyme concentration required to obtain the maximum particle size reduction increased from 200 to 1000 mg/l. A 4-h pretreatment with PL-250 also increased the free long-chain fatty acid (LCFA) concentration to a maximum of 15.5 mg/l, indicating some solubilization of the pork fat particles in SHW. SCOD was not significantly increased by the pretreatment, but SCOD was not found to be a good indicator of enzymatic lipolysis because of enzyme adsorption on the fat particle surface. Pancreatic lipase appeared more efficient with beef fat than pork fat, possibly because beef fat contains less polyunsaturated fatty acids than pork fat. The bacterial lipase LG-1000 was also efficient in reducing average fat particle size, but high doses (> 1000 mg/l) were required to obtain a significant reduction after 4 h of pretreatment. SCOD was not increased by pretreatment with LG-1000. No particle size reduction or changes in SCOD were noted after 4 h of pretreatment with the plant lipase EcoSystem Plus. It was concluded that PL-250 was the best pretreatment to hydrolyse fat particles in SHW. However, its impact on the efficiency of a downstream anaerobic digestion process remains to be tested.

  11. Forms and Lability of Phosphorus in Algae and Aquatic Macrophytes Characterized by Solution 31P NMR Coupled with Enzymatic Hydrolysis

    Science.gov (United States)

    Feng, Weiying; Zhu, Yuanrong; Wu, Fengchang; He, Zhongqi; Zhang, Chen; Giesy, John P.

    2016-11-01

    Solution Phosphorus-31 nuclear magnetic resonance (31P NMR) spectroscopy coupled with enzymatic hydrolysis (EH) with commercially available phosphatases was used to characterize phosphorus (P) compounds in extracts of the dominant aquatic macrophytes and algae in a eutrophic lake. Total extractable organic P (Po) concentrations ranged from 504 to 1643 mg kg-1 and 2318 to 8395 mg kg-1 for aquatic macrophytes and algae, respectively. Using 31P NMR spectroscopy, 11 Po species were detected in the mono- and diester region. Additionally, orthophosphate, pyrophosphate and phosphonates were also detected. Using EH, phytate-like P was identified as the prevalent class of enzyme-labile Po, followed by labile monoester- and diester-P. Comparison of the NMR and EH data indicated that the distribution pattern of major P forms in the samples determined by the two methods was similar (r = 0.712, p < 0.05). Additional 31P NMR spectroscopic analysis of extracts following EH showed significant decreases in the monoester and pyrophosphate regions, with a corresponding increase in the orthophosphate signal, as compared to unhydrolyzed extracts. Based on these quantity and hydrolysis data, we proposed that recycling of Po in vegetative biomass residues is an important mechanism for long-term self-regulation of available P for algal blooming in eutrophic lakes.

  12. Effect of enzymatic hydrolysis of pancreatin and alcalase enzyme on some properties of edible bird's nest hydrolysate

    Science.gov (United States)

    Khushairay, Etty Syarmila Ibrahim; Ayub, Mohd Khan; Babji, Abdul Salam

    2014-09-01

    Edible bird nest (EBN) is a dried glutinous secretion from the salivary glands of several different swiftlet species. It is widely consumed as a health food due to its high beneficial effects to human health and has been considered to be one of the most precious food items by the Chinese for thousands of years. The aim of this study was to evaluate the effect of enzymatic hydrolysis on protein solubility (μg/g), the degree of hydrolysis (DH%), and peptide content (μg/g) of edible bird's nest hydrolysate. Initial protein solubility of boiled EBN was 25.5mg/g EBN. Treating the solubilized EBN with pancreatin 4NF for 1.0 - 1.5hours increased EBN protein solubility to 163.9mg/g and produced hydrolysate with DH% of 86.5% and 109.5mg/g peptide. EBN hydrolyzed with alcalase for 1.5 hours produced hydrolysate with protein solubility of 86.7mg/g, 82.7 DH% and had 104.1mg/g peptide content.

  13. Statistically designed enzymatic hydrolysis of an icariin/β-cyclodextrin inclusion complex optimized for production of icaritin

    Directory of Open Access Journals (Sweden)

    Xin Jin

    2012-02-01

    Full Text Available This study focuses on the preparation and enzymic hydrolysis of an icariin/β-cyclodextrin inclusion complex to efficiently generate icaritin. The physical characteristics of the inclusion complex were evaluated by differential scanning calorimetry (DSC. Enzymatic hydrolysis was optimized for the conversion of icariin/β-cyclodextrin complex to icaritin by Box–Behnken statistical design. The inclusion complex formulation increased the solubility of icariin approximately 17-fold, from 29.2 to 513.5 μg/mL at 60 °C. The optimum conditions were predicted by Box–Behnken statistical design as follows: 60 °C, pH 7.0, the ratio of enzyme/substrate (1:1.1 and reaction time 7 h. Under the optimal conditions the conversion of icariin was 97.91% and the reaction time was decreased by 68% compared with that without β-CD inclusion. Product analysis by melting point, ESI-MS, UV, IR, 1H NMR and 13C NMR confirmed the authenticity of icaritin with a purity of 99.3% and a yield of 473 mg of icaritin from 1.1 g icariin.

  14. Comparison between wet oxidation and steam explosion as pretreatment methods for enzymatic hydrolysis of sugarcane bagasse

    DEFF Research Database (Denmark)

    Medina, Carlos Martín; Marcet, M.; Thomsen, Anne Belinda

    2008-01-01

    , and to a two-fold increase of cellulose content in the pretreated solids, while steam explosion solubilised only 60% of xylan and 35% of lignin and increased cellulose content in the solid material by one third. Wet oxidation formed more aliphatic acids and phenolics, and less furan aldehydes in the liquid......Alkaline wet oxidation and steam explosion pretreatments of sugarcane bagasse were compared with regard to biomass fractionation, formation of by-products, and enzymatic convertibility of the pretreated material. Wet oxidation led to the solubilisation of 82% of xylan and 50% of lignin...... fraction than steam explosion did. A better enzymatic convertibility of cellulose was achieved for the wet-oxidised material (57.4 %) than for the steam-exploded material (48.9 %). Cellulose convertibility was lower for the whole slurry than for the washed solids in both pretreatments, but more...

  15. Determination of carbon isotope ratios in plant starch via selective enzymatic hydrolysis

    International Nuclear Information System (INIS)

    Schimmelmann, A.; DeNiro, M.J.

    1983-01-01

    A method for the determination of the carbon isotope ratios in bipolymers hydrolyzed by enzymatic action consists of separating the monomer by passage through a dialysis membrane and then combusting the monomer prior to isotopic analysis. The method is described for application to the analysis of starch, but it should find application for polymers than can be degraded quantitatively to monomers and/or oligomers using specific hydrolytic enzymes

  16. Effects of SPORL and dilute acid pretreatment on substrate morphology, cell physical and chemical wall structures, and subsequent enzymatic hydrolysis of lodgepole pine

    Science.gov (United States)

    Xinping Li; Xiaolin Luo; Kecheng Li; J.Y. Zhu; J. Dennis Fougere; Kimberley Clarke

    2012-01-01

    The effects of pretreatment by dilute acid and sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) on substrate morphology, cell wall physical and chemical structures, along with the subsequent enzymatic hydrolysis of lodgepole pine substrate were investigated. FE-SEM and TEM images of substrate structural morphological changes showed that SPORL...

  17. Using temperature-responsive zwitterionic surfactant to enhance the enzymatic hydrolysis of lignocelluloses and recover cellulase by cooling.

    Science.gov (United States)

    Cai, Cheng; Pang, Yuxia; Zhan, Xuejuan; Zeng, Meijun; Lou, Hongming; Qian, Yong; Yang, Dongjie; Qiu, Xueqing

    2017-11-01

    Some zwitterionic surfactants exhibit upper critical solution temperature (UCST) in aqueous solutions. For the zwitterionic surfactant solution mixed with cellulase, when its temperature is below UCST, the cellulase can be recovered by coprecipitation with zwitterionic surfactant. In this work, 3-(Hexadecyldimethylammonio) propanesulfonate (SB3-16) was selected to enhance the enzymatic hydrolysis of lignocelluloses and recover the cellulase. After adding 2mmol/L of SB3-16, the enzymatic digestibility of eucalyptus pretreated by dilute acid (Eu-DA) and by sulfite (Eu-SPORL) increased from 27.9% and 35.1% to 72.6% and 89.7%, respectively. The results showed that SB3-16 could reduce the non-productive adsorption of cellulase on hydrophobic interface, while it did not significantly inhibit the activity of cellulase. For the solution contained 1wt% SB3-16 and 200mg protein/L CTec2 cellulase, 55.2% of protein could be recovered by cooling. The filter paper activity of the recovered cellulase was 1.93FPU/mg protein, which was 95.8% of its initial activity. Copyright © 2017. Published by Elsevier Ltd.

  18. STUDY OF THE PREPARATION OF SUGAR FROM HIGH-LIGNIN LIGNOCELLULOSE APPLYING SUBCRITICAL WATER AND ENZYMATIC HYDROLYSIS: SYNTHESIS AND CONSUMABLE COST EVALUATION

    Directory of Open Access Journals (Sweden)

    HANNY F. SANGIAN

    2015-05-01

    Full Text Available This study concern sugars hydrolyzed from the high-lignin coconut coir dust using moderate subcritical water (SCW hydrolysis at pressures 20-40 bar for 1 h and to evaluate the consumable costs driver generated. The SCW method produced two products, sugar liquid and solid (SCW-treated substrate. The solid was proceeded to prepare the sugar via enzymatic hydrolysis using pure cellulase. Yield of sugar hydrolyzed from lignocellulose by SCW technique was 0.25 gram sugar/gram cellulose +hemicellulose, or 0.09-gram sugar/gram lignocellulose at 160 °C and 40 bar. While, the maximum yield of sugar liberated enzymatically from SCW-treated solid was 0.35-gram sugar/gram cellulose+hemicellulose, or 0.13-gram sugar/gram SCW-treated solid. It was found that carbon dioxide gas was the highest cost driving in SCW hydrolysis.

  19. Effects of SPORL and dilute acid pretreatment on substrate morphology, cell physical and chemical wall structures, and subsequent enzymatic hydrolysis of lodgepole pine.

    Science.gov (United States)

    Li, Xinping; Luo, Xiaolin; Li, Kecheng; Zhu, J Y; Fougere, J Dennis; Clarke, Kimberley

    2012-11-01

    The effects of pretreatment by dilute acid and sulfite pretreatment to overcome recalcitrance of lignocellulose (SPORL) on substrate morphology, cell wall physical and chemical structures, along with the subsequent enzymatic hydrolysis of lodgepole pine substrate were investigated. FE-SEM and TEM images of substrate structural morphological changes showed that SPORL pretreatment resulted in fiber separation, where SPORL high pH (4.2) pretreatment exhibited better fiber separation than SPORL low pH (1.9) pretreatment. Dilute acid pretreatment produced very poor fiber separation, consisting mostly of fiber bundles. The removal of almost all hemicelluloses in the dilute acid pretreated substrate did not overcome recalcitrance to achieve a high cellulose conversion when lignin removal was limited. SPORL high pH pretreatment removed more lignin but less hemicellulose, while SPORL low pH pretreatment removed about the same amount of lignin and hemicelluloses in lodgepole pine substrates when compared with dilute acid pretreatment. Substrates pretreated with either SPORL process had a much higher cellulose conversion than those produced with dilute acid pretreatment. Lignin removal in addition to removal of hemicellulose in SPORL pretreatment plays an important role in improving the cellulose hydrolysis of the substrate.

  20. Reactor design for minimizing product inhibition during enzymatic lignocellulose hydrolysis: I. Significance and mechanism of cellobiose and glucose inhibition on cellulolytic enzymes

    DEFF Research Database (Denmark)

    Andric, Pavle; Meyer, Anne S.; Jensen, Peter Arendt

    2010-01-01

    Achievement of efficient enzymatic degradation of cellulose to glucose is one of the main prerequisites and one of the main challenges in the biological conversion of lignocellulosic biomass to liquid fuels and other valuable products. The specific inhibitory interferences by cellobiose and glucose...... on enzyme-catalyzed cellulose hydrolysis reactions impose significant limitations on the efficiency of lignocellulose conversion especially at high-biomass dry matter conditions. To provide the base for selecting the optimal reactor conditions, this paper reviews the reaction kinetics, mechanisms......, and significance of this product inhibition, notably the cellobiose and glucose inhibition, on enzymatic cellulose hydrolysis. Particular emphasis is put on the distinct complexity of cellulose as a substrate, the multi-enzymatic nature of the cellulolytic degradation, and the particular features of cellulase...

  1. Building blocks for the solution phase synthesis of oligonucleotides: regioselective hydrolysis of 3',5'-Di-O-levulinylnucleosides using an enzymatic approach.

    Science.gov (United States)

    García, Javier; Fernández, Susana; Ferrero, Miguel; Sanghvi, Yogesh S; Gotor, Vicente

    2002-06-28

    A short and convenient synthesis of 3'- and 5'-O-levulinyl-2'-deoxynucleosides has been developed from the corresponding 3',5'-di-O-levulinyl derivatives by regioselective enzymatic hydrolysis, avoiding several tedious chemical protection/deprotection steps. Thus, Candida antartica lipase B (CAL-B) was found to selectively hydrolyze the 5'-levulinate esters, furnishing 3'-O-levulinyl-2'-deoxynucleosides 3 in >80% isolated yields. On the other hand, immobilized Pseudomonas cepacia lipase (PSL-C) and Candida antarctica lipase A (CAL-A) exhibit the opposite selectivity toward the hydrolysis at the 3'-position, affording 5'-O-levulinyl derivatives 4 in >70% yields. A similar hydrolysis procedure was successfully extended to the synthesis of 3'- and 5'-O-levulinyl-protected 2'-O-alkylribonucleosides 7 and 8. This work demonstrates for the first time application of commercial CAL-B and PSL-C toward regioselective hydrolysis of levulinyl esters with excellent selectivity and yields. It is noteworthy that protected cytidine and adenosine base derivatives were not adequate substrates for the enzymatic hydrolysis with CAL-B, whereas PSL-C was able to accommodate protected bases during selective hydrolysis. In addition, we report an improved synthesis of dilevulinyl esters using a polymer-bound carbodiimide as a replacement for dicyclohexylcarbodiimide (DCC), thus considerably simplifying the workup for esterification reactions.

  2. Enzymatic hydrolysis of cellulosic materials by Sclerotium rolfsii culture filtrate for sugar production

    Energy Technology Data Exchange (ETDEWEB)

    Shewale, J G; Sadana, J C

    1979-06-01

    The hydrolysis of purified celluloses (cotton, Avicel, Cellulose-123, Solka Floc SW40) and cellulosic wastes (rice straw, sugarcane bagasse, wood powders, paper factory effluents) by Sclerotium rolfsii CPC 142 culture filtrate was studied. Factors which effect saccharification such as pH, temperature, enzyme concentration, substrate concentration, produce inhibition, adsorption, and inactivation of enzyme and particle size were studied. Virtually no inhibition (less than 3%) of cellulose hydrolysis by the culture filtrate was observed by cellobiose and glucose up to 100 mg/mL. Filter paper degrading enzyme(s) (but neither carboxymethylcellulase nor beta-glucosidase) was adsorbed on cellulose. The n value in the S. rolfsii system was calculated to be 0.32 for Avicel P.H. 101 and 0.53 for alkali-treated (AT) rice straw indicating penetration of cellulase into AT rice straw. In batch experiments at 10% substrate level, solutions containing 6 to 7%, 3.8 to 4.7%, 4.0 to 5.1%, and 4.2 to 4.9% reducing sugars were produced in 24 to 48 from AT rice straw. AT bagasse, alkali - peracetic acid treated mesta wood and paper factory sedimented sludge effluent, respectively. The main constituent in the hydrolysate from cellulose was glucose with little or no cellobiose, probably due to the high cellobiase content in the culture filtrate.

  3. Starch: chemistry, microstructure, processing and enzymatic degradation

    Science.gov (United States)

    Starch is recognized as one of the most abundant and important commodities containing value added attributes for a vast number of industrial applications. Its chemistry, structure, property and susceptibility to various chemical, physical and enzymatic modifications offer a high technological value ...

  4. Effects of laccase on lignin depolymerization and enzymatic hydrolysis of ensiled corn stover.

    Science.gov (United States)

    Chen, Qin; Marshall, Megan N; Geib, Scott M; Tien, Ming; Richard, Tom L

    2012-08-01

    The aim of this study was to explore the synergies of laccase, a ligninolytic enzyme, with cellulose and hemicellulase amendments on ensiled corn stover. Molecular signals of lignin decomposition were observed by tetramethylammonium hydroxide thermochemolysis and gas chromatography-mass spectroscopy (TMAH-GC-MS) analysis. The significant findings suggest that ensilage might provide a platform for biological pretreatment. By partially hydrolyzing cellulose and hemicellulose into soluble sugars, ensilage facilitates laccase penetration into the lignocellulose complex to enhance lignin degradation. Downstream cellulose hydrolysis was improved 7% with increasing laccase loading rate. These results demonstrate the potential of enzymes, either directly amended or expressed by microbes during ensilage, to maximize utilization of corn stover for cellulosic biofuels and other downstream fermentations. Copyright © 2012. Published by Elsevier Ltd.

  5. Product inhibition of enzymatic hydrolysis of cellulose: are we running the reactions all wrong?

    DEFF Research Database (Denmark)

    Meyer, Anne S.

    2012-01-01

    cellobiose and glucose. The reported KI for glucose on the T. reesei cellulases and -glucosidase varies from 0.04 to 5 g/L. The type of inhibition is debated, and probably varies for different -glucosidases, but with a required goal of sufficient glucose concentration to support ethanol concentrations....... This is because the currently used Trichoderma reesei derived cellulases, i.e. exoglucanases (mainly the cellobiohydrolases Cel7A and Cel6A), endo-1,4--glucanases, and now boosted with -glucosidase and other enzymes, now considered the “industry standard” enzymes, are significantly inhibited by the products...... of minimum ∼5–6% v/v, the glucose product concentrations exceed the critical limit for product inhibition. Hence, regardless of the recent progress in enzyme development for cellulose hydrolysis, the glucose product inhibition remains an issue, which is exacerbated as the reaction progresses, especially...

  6. Separate and Simultaneous enzymatic hydrolysis and fermentation of wheat hemicellulose with recombinant xylose utilizing Saccharomyces cerevisiae

    DEFF Research Database (Denmark)

    Olsson, Lisbeth; Sørensen, H. R.; Dam, B. P

    2006-01-01

    Fermentations with three different xylose-utilizing recombinant Saccharomyces cerevisiae strains (F12, CR4, and CB4) were performed using two different wheat hemicellulose substrates, unfermented starch free fibers, and an industrial ethanol fermentation residue, vinasse. With CR4 and F12......, the maximum ethanol concentrations obtained were 4.3 and 4 g/L, respectively, but F12 converted xylose 15% faster than CR4 during the first 24 h. The comparison of separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) with F12 showed that the highest, maximum...... ethanol concentrations were obtained with SSF. In general, the volumetric ethanol productivity was initially, highest in the SHF, but the overall volumetric ethanol productivity ended up being maximal in the SSF, at 0.013 and 0.010 g/Lh, with starch free fibers and vinasse, respectively....

  7. Enzymatic synthesis of S-phenyl-L-cysteine from keratin hydrolysis industries wastewater with tryptophan synthase.

    Science.gov (United States)

    Xu, Lisheng; Wang, Zhiyuan; Mao, Pingting; Liu, Junzhong; Zhang, Hongjuan; Liu, Qian; Jiao, Qing-Cai

    2013-04-01

    An economical method for production of S-phenyl-L-cysteine from keratin acid hydrolysis wastewater (KHW) containing L-serine was developed by recombinant tryptophan synthase. This study provides us with an alternative KHW utilization strategy to synthesize S-phenyl-L-cysteine. Tryptophan synthase could efficiently convert L-serine contained in KHW to S-phenyl-L-cysteine at pH 9.0, 40°C and Trion X-100 of 0.02%. In a scale up study, L-serine conversion rate reach 97.1% with a final S-phenyl-L-cysteine concentration of 38.6 g l(-1). Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Comparison of Microwave and Ozonolysis Effect as Pretreatment on Sugarcane Bagasse Enzymatic Hydrolysis

    Directory of Open Access Journals (Sweden)

    N Eqra

    2015-03-01

    Full Text Available Bioethanol production from agricultural residues is one of the promising methods. Pretreatment is the most important step in this type of bioethanol production. In this study, the saccharification percentage of sugarcane bagasse was investigated after two types of pretreatments including ozone steaming and microwave. Microwave pretreatment was studied with two factors of microwave radiation (170, 450, and 850 w and microwave duration (2, 6, and 10 min. The ozonolysis (ozone steaming pretreatment was surveyed with two factors of moisture content of bagasse (30, 40, and 50% and ozonolysis time (1.5, 2.5, 3.5, and 4.5 hr. After hydrolysis, the Saccharification percentage of sugarcane bagasse increased to 57.2% and 67.06% with microwave and ozonolysis pretreatments, respectively; compare to 20.85% in non-ozonated bagasse. It can be concluded that the ozonolysis is the most effective pretreatment regarding to saccharification percentage of sugarcane bagasse.

  9. Improving the enzymatic hydrolysis of thermo-mechanical fiber from Eucalyptus urophylla by a combination of hydrothermal pretreatment and alkali fractionation.

    Science.gov (United States)

    Sun, Shaoni; Cao, Xuefei; Sun, Shaolong; Xu, Feng; Song, Xianliang; Sun, Run-Cang; Jones, Gwynn Lloyd

    2014-01-01

    The recalcitrance of lignocellulosic biomass is a major limitation for its conversion into biofuels by enzymatic hydrolysis. The use of a pretreatment technology is an essential step to diminish biomass recalcitrance for bioethanol production. In this study, a two-step pretreatment using hydrothermal pretreatment at various temperatures and alkali fractionation was performed on eucalyptus fiber. The detailed chemical composition, physicochemical characteristics, and morphology of the pretreated fibers in each of the fractions were evaluated to advance the performance of eucalyptus fiber in enzymatic digestibility. The hydrothermal pretreatment (100 to 220°C) significantly degraded hemicelluloses, resulting in an increased crystallinity of the pretreated fibers. However, as the pretreatment temperature reached 240°C, partial cellulose was degraded, resulting in a reduced crystallinity of cellulose. As compared to the hydrothermal pretreatment alone, a combination of hydrothermal and alkali treatments significantly removed hemicelluloses and lignin, resulting in an improved enzymatic hydrolysis of the cellulose-rich fractions. As compared with the raw fiber, the enzymatic hydrolysis rate increased 1.1 to 8.5 times as the hydrothermal pretreatment temperature increased from 100 to 240°C. Interestingly, after a combination of hydrothermal pretreatment and alkali fractionation, the enzymatic hydrolysis rate increased 3.7 to 9.2 times. Taking into consideration the consumption of energy and the production of xylo-oligosaccharides and lignin, an optimum pretreatment condition was found to be hydrothermal pretreatment at 180°C for 30 min and alkali fractionation with 2% NaOH at 90°C for 2.5 h, in which 66.3% cellulose was converted into glucose by enzymatic hydrolysis. The combination of hydrothermal pretreatment and alkali fractionation was a promising method to remove hemicelluloses and lignin as well as overcome the biomass recalcitrance for enzymatic hydrolysis

  10. Synthesis and spectral characterization of 2,2-diphenylethyl glucosinolate and HPLC-based reaction progress curve data for the enzymatic hydrolysis of glucosinolates by Sinapis alba myrosinase

    Directory of Open Access Journals (Sweden)

    Chase A. Klingaman

    2017-02-01

    Full Text Available The data presented in this article are related to the research article, “HPLC-based enzyme kinetics assay for glucosinolate hydrolysis facilitate analysis of systems with both multiple reaction products and thermal enzyme denaturation” (C.K. Klingaman, M.J. Wagner, J.R. Brown, J.B. Klecker, E.H. Pauley, C.J. Noldner, J.R. Mays, [1]. This data article describes (1 the synthesis and spectral characterization data of a non-natural glucosinolate analogue, 2,2-diphenylethyl glucosinolate, (2 HPLC standardization data for glucosinolate, isothiocyanate, nitrile, and amine analytes, (3 reaction progress curve data for enzymatic hydrolysis reactions with variable substrate concentration, enzyme concentration, buffer pH, and temperature, and (4 normalized initial velocities of hydrolysis/formation for analytes. These data provide a comprehensive description of the enzyme-catalyzed hydrolysis of 2,2-diphenylethyl glucosinolate (5 and glucotropaeolin (6 under widely varied conditions.

  11. Application of Ni(II-assisted peptide bond hydrolysis to non-enzymatic affinity tag removal.

    Directory of Open Access Journals (Sweden)

    Edyta Kopera

    Full Text Available In this study, we demonstrate a non-enzymatic method for hydrolytic peptide bond cleavage, applied to the removal of an affinity tag from a recombinant fusion protein, SPI2-SRHWAP-His(6. This method is based on a highly specific Ni(II reaction with (S/TXHZ peptide sequences. It can be applied for the protein attached to an affinity column or to the unbound protein in solution. We studied the effect of pH, temperature and Ni(II concentration on the efficacy of cleavage and developed an analytical protocol, which provides active protein with a 90% yield and ∼100% purity. The method works well in the presence of non-ionic detergents, DTT and GuHCl, therefore providing a viable alternative for currently used techniques.

  12. Chemical characterization and hydrothermal pretreatment of Salicornia bigelovii straw for enhanced enzymatic hydrolysis and bioethanol potential

    DEFF Research Database (Denmark)

    Cybulska, Iwona; Chaturvedi, Tanmay; Brudecki, Grzegorz P.

    2014-01-01

    equipment and avoid inhibition of enzymes and yeast. Composition of the washed biomass was comparable to traditional lignocellulosic biomasses with relatively high glucan and xylan content (26 and 22. g/100. gDM, respectively) but with lower lignin content (7. g/100. gDM). The washed feedstock was subjected...... to hydrothermal pretreatment, producing highly digestible (up to 92% glucan-to-glucose conversion) and fermentable (up to 100% glucose-to-ethanol conversion) fiber fractions. Liquid fractions obtained in the pretreatment did not show inhibition towards Saccharomyces cerevisiae. No significant differences among...... the enzymatic convertibility and microbial fermentability of the fibers as well as low xylose recoveries suggest that lower severity pretreatment conditions could be exploited for S. bigelovii. © 2013 Elsevier Ltd....

  13. Electrospray ionization mass spectrometry for the hydrolysis complexes of cisplatin: implications for the hydrolysis process of platinum complexes.

    Science.gov (United States)

    Feifan, Xie; Pieter, Colin; Jan, Van Bocxlaer

    2017-07-01

    Non-enzyme-dependent hydrolysis of the drug cisplatin is important for its mode of action and toxicity. However, up until today, the hydrolysis process of cisplatin is still not completely understood. In the present study, the hydrolysis of cisplatin in an aqueous solution was systematically investigated by using electrospray ionization mass spectrometry coupled to liquid chromatography. A variety of previously unreported hydrolysis complexes corresponding to monomeric, dimeric and trimeric species were detected and identified. The characteristics of the Pt-containing complexes were investigated by using collision-induced dissociation (CID). The hydrolysis complexes demonstrate distinctive and correlative CID characteristics, which provides tools for an informative identification. The most frequently observed dissociation mechanism was sequential loss of NH 3 , H 2 O and HCl. Loss of the Pt atom was observed as the final step during the CID process. The formation mechanisms of the observed complexes were explored and experimentally examined. The strongly bound dimeric species, which existed in solution, are assumed to be formed from the clustering of the parent compound and its monohydrated or dihydrated complexes. The role of the electrospray process in the formation of some of the observed ions was also evaluated, and the electrospray ionization-related cold clusters were identified. The previously reported hydrolysis equilibria were tested and subsequently refined via a hydrolysis study resulting in a renewed mechanistic equilibrium system of cisplatin as proposed from our results. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  14. Enhancement of enzymatic hydrolysis of corn stover by γ-irradiation and combined solvent delignification/acid prehydrolysis

    International Nuclear Information System (INIS)

    Nghiem, N.P.; Gonzales-Valdes, A.; Moo-Young, M.; Robinson, C.W.

    1984-01-01

    Two pretreatment schemes were studied for their effect on the enhancement of soluble sugar production from corn stover by enzymatic hydrolysis. In the first scheme, prior to enzymic hydrolysis corn stover which was ground to pass a 1 mm screen was immersed in NaOH solution and exposed to gamma irradiation. The NaOH levels and radiation dosages were varied from 0 to 0.51 gNaOH/g corn stover and from 50 to 150 Mr, respectively. The combined residue and solubles were then hydrolyzed with a commercial cellulase (Onozuka) in 0.05 M citrate buffer at pH 4.6 and 39 0 C for 48 hours. The highest sugar yield of 96% based on the total carbohydrate content of the original sample was obtained at 100 Mr and 0.06 gNaOH/g corn stover. In the second scheme, corn stover which was ground to pass a 0.35 mm screen was delignified with ethanol-water-NaOH. The ethanol-water mixture used contained 3 parts (by volume) of 95% ethanol and 4 g NaOH/L; substrate concentration was 5% (w/v). The delignification was carried out at 140 0 C for 1 hour. At these conditions, 65% of the lignin was removed while 90% of the carbohydrates remained insoluble. The delignified corn stover with an without treatment using 2% wt.% H 2 SO 4 at 95 0 C and 1 hour was then enzymically hydrolyzed with Novo Cellulclast at pH 4.8 and 50 0 C for up to 48 hours. Factors that affect the overall sugar production are presented and discussed. In addition, the overall sugar yields for the two schemes are compared with other pretreatment schemes reported. (orig.)

  15. Scale-up of ethanol production from winter barley by the EDGE (enhanced dry grind enzymatic) process in fermentors up to 300 liters

    Science.gov (United States)

    A fermentation process, which was designated the EDGE (enhanced dry grind enzymatic) process, has recently been developed for barley ethanol production. In the EDGE process, in addition to the enzymes normally required for starch hydrolysis, commercial Beta-glucanases were used to hydrolyze (1,3)(1,...

  16. Enzymatic hydrolysis of starch in the presence of cereal soluble fibre polysaccharides.

    Science.gov (United States)

    Dhital, Sushil; Dolan, Grace; Stokes, Jason R; Gidley, Michael J

    2014-03-01

    The in vitro amylolysis of both granular and cooked maize starch and the diffusion of glucose in the presence of 1% and 2% cereal soluble fibre polysaccharides (arabinoxylan and mixed linkage beta-glucan) were studied at various levels of shear mixing in order to identify potential molecular mechanisms underlying observed glycemia-reducing effects of soluble fibres in vivo. The presence of soluble fibres increased viscosity by ca. 10× and 100× for 1% and 2% concentrations respectively. Despite this large difference in viscosity, measured digestion and mass transfer coefficients were only reduced by a factor of 1.5 to 2.5 at the same mixing speed. In contrast, introduction of mixing in the digesting and diffusing medium significantly increased the rate of amylolytic starch digestion and mass transfer of glucose. This effect is such that mixing at high speeds negates the hindering effect of the 100× increased viscosity imparted by the presence of 2% soluble fibre; this is essentially captured by the Reynolds number (the ratio of inertial and viscous forces) that defines the flow kinematics. The modest reduction of in vitro starch hydrolysis and glucose diffusion at increased viscosity suggests that the established benefits of soluble fibres on post-prandial glycaemia, in terms of attenuation of the overall rate and extent of dietary starch conversion to blood glucose, are not primarily due to a direct effect of viscosity. Alternative hypotheses are proposed based on gastric emptying, restriction of turbulent flow, and/or stimulation of mucus turnover.

  17. Optimization of pretreatment, enzymatic hydrolysis and fermentation for more efficient ethanol production by Jerusalem artichoke stalk.

    Science.gov (United States)

    Li, Kai; Qin, Jin-Cheng; Liu, Chen-Guang; Bai, Feng-Wu

    2016-12-01

    Jerusalem artichoke (JA) is a potential energy crop for biorefinery due to its unique agronomic traits such as resistance to environmental stresses and high biomass yield in marginal lands. Although JA tubers have been explored for inulin extraction and biofuels production, there is little concern on its stalk (JAS). In this article, the pretreatment of JAS by alkaline hydrogen peroxide was optimized using the response surface methodology to improve sugars yield and reduce chemicals usage. Scanning electron microscopy, X-ray diffraction, and thermogravimetric analysis were applied to characterize the structures of the pretreated JAS to evaluate the effectiveness of the pretreatment. Furthermore, the feeding of the pretreated JAS and cellulase was performed for high solid uploading (up to 30%) to increase ethanol titer, and simultaneous saccharification and fermentation with 55.6g/L ethanol produced, 36.5% more than that produced through separate hydrolysis and fermentation, was validated to be more efficient. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Effect of enzymatic hydrolysis on bioactive properties and allergenicity of cricket (Gryllodes sigillatus) protein.

    Science.gov (United States)

    Hall, Felicia; Johnson, Philip E; Liceaga, Andrea

    2018-10-01

    Food-derived bioactive peptides have gained attention for their role in preventing chronic diseases. Edible insects are viable sources of bioactive peptides owing to their high protein content and sustainable production. In this study, whole crickets (Gryllodes sigillatus) were alcalase-hydrolyzed to a degree of hydrolysis (DH) ranging from 15 to 85%. Antioxidant activity, angiotensin converting enzyme (ACE), and dipeptidyl peptidase-4 (DPP-IV)- inhibition of the cricket protein hydrolysates (CPH) were evaluated before and after simulated gastrointestinal digestion (SGD). Antioxidant activity was similar among CPH, whereas ACE and DPP-IV inhibition was greater (p < 0.05) in CPH with 60-85% DH. Bioactivity improved after SGD. CPH allergenicity was evaluated using human shrimp-allergic sera. All sera positively reacted to tropomyosin in the unhydrolyzed cricket and CPH with 15-50% DH, whereas 60-85% DH showed no reactivity. In conclusion, CPH (60-85% DH) had the greatest bioactive potential and lowest reactivity to tropomyosin, compared with other CPH and the unhydrolyzed control. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Removal of chromophore in enzymatic hydrolysis by acid precipitation to improve the quality of xylo-oligosaccharides from corn stalk.

    Science.gov (United States)

    Wang, Yue-Hai; Zhang, Jie; Qu, Yong-Shui; Li, Hong-Qiang

    2018-02-01

    As the most representative functional sugar, the application areas and market demands of xylo-oligosaccharides (XOS) have been expanding year by year. Owing to the complex structure of corn stalk (CS), XOS obtained from CS are accompanied by problems such as low purity and high color value, which degrade the product. To improve the quality of XOS from CS, the enzymatic hydrolysis was precipitated by acid; then, the ethanol elution concentration was systematically investigated after optimizing the adsorption conditions. The results showed that the purity of XOS was increased to 87.28% from 67.31%, and the color value was decreased to 1050 from 4682 when the acid precipitation pH was 2. On the basis of acid precipitation, if the corresponding optimal conditions of XOS adsorption and elution were used, the highest purity of XOS was 97.87% obtained, with the lowest color value, 780, which reached the standard of the commercial XOS. Copyright © 2017. Published by Elsevier Ltd.

  20. Direct lactic acid fermentation of Jerusalem artichoke tuber extract using Lactobacillus paracasei without acidic or enzymatic inulin hydrolysis.

    Science.gov (United States)

    Choi, Hwa-Young; Ryu, Hee-Kyoung; Park, Kyung-Min; Lee, Eun Gyo; Lee, Hongweon; Kim, Seon-Won; Choi, Eui-Sung

    2012-06-01

    Lactic acid fermentation of Jerusalem artichoke tuber was performed with strains of Lactobacillus paracasei without acidic or enzymatic inulin hydrolysis prior to fermentation. Some strains of L. paracasei, notably KCTC13090 and KCTC13169, could ferment hot-water extract of Jerusalem artichoke tuber more efficiently compared with other Lactobacillus spp. such as L. casei type strain KCTC3109. The L. paracasei strains could utilize almost completely the fructo-oligosaccharides present in Jerusalem artichoke. Inulin-fermenting L. paracasei strains produced c.a. six times more lactic acid compared with L. casei KCTC3109. Direct lactic fermentation of Jerusalem artichoke tuber extract at 111.6g/L of sugar content with a supplement of 5 g/L of yeast extract by L. paracasei KCTC13169 in a 5L jar fermentor produced 92.5 ce:hsp sp="0.25"/>g/L of lactic acid with 16.8 g/L fructose equivalent remained unutilized in 72 h. The conversion efficiency of inulin-type sugars to lactic acid was 98% of the theoretical yield. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Process technology for multi-enzymatic reaction systems

    DEFF Research Database (Denmark)

    Xue, Rui; Woodley, John M.

    2012-01-01

    In recent years, biocatalysis has started to provide an important green tool in synthetic organic chemistry. Currently, the idea of using multi-enzymatic systems for industrial production of chemical compounds becomes increasingly attractive. Recent examples demonstrate the potential of enzymatic...... synthesis and fermentation as an alternative to chemical-catalysis for the production of pharmaceuticals and fine chemicals. In particular, the use of multiple enzymes is of special interest. However, many challenges remain in the scale-up of a multi-enzymatic system. This review summarizes and discusses...... the technology options and strategies that are available for the development of multi-enzymatic processes. Some engineering tools, including kinetic models and operating windows, for developing and evaluating such processes are also introduced....

  2. The enzymatic hydrolysis of soy protein isolate by Corolase PP under high hydrostatic pressure and its effect on bioactivity and characteristics of hydrolysates.

    Science.gov (United States)

    Guan, Haining; Diao, Xiaoqin; Jiang, Fan; Han, Jianchun; Kong, Baohua

    2018-04-15

    Enzymatic hydrolysis of soy protein isolate by Corolase PP under high hydrostatic pressure conditions was studied and the effects of hydrolysis on antioxidant and antihypertensive activities were investigated. As observed, high hydrostatic pressure (80-300MPa) enhanced the hydrolytic efficiency of Corolase PP and decreased the surface hydrophobicity of the hydrolysates. Hydrolysates obtained at 200MPa for 4h had higher bioactivities (reducing power, ABTS radical-scavenging and ACE inhibitory activities). The molecular weight (MW) determination indicated that hydrolysis at high hydrostatic pressure could increase the production of small peptides (hydrostatic pressure combined with Corolase PP treatments could be used as a potential technology to produce bioactive peptides from soy protein isolate. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Enzymatic Hydrolysis of biomasses having a high dry matter (DM) content

    DEFF Research Database (Denmark)

    2010-01-01

    that the biomasses are subjected to mechanical forces, primarily shear and tear forces. Furthermore, the present invention relates to the further utilization of such processed biomasses, e.g. for subsequent fermentation into bio-ethanol, bio-gas, specialty carbohydrates for food and fees as well as carbon feedstock...... for processing into plastics and chemicals....

  4. NREL 2012 Achievement of Ethanol Cost Targets: Biochemical Ethanol Fermentation via Dilute-Acid Pretreatment and Enzymatic Hydrolysis of Corn Stover

    Energy Technology Data Exchange (ETDEWEB)

    Tao, L.; Schell, D.; Davis, R.; Tan, E.; Elander, R.; Bratis, A.

    2014-04-01

    For the DOE Bioenergy Technologies Office, the annual State of Technology (SOT) assessment is an essential activity for quantifying the benefits of biochemical platform research. This assessment has historically allowed the impact of research progress achieved through targeted Bioenergy Technologies Office funding to be quantified in terms of economic improvements within the context of a fully integrated cellulosic ethanol production process. As such, progress toward the ultimate 2012 goal of demonstrating cost-competitive cellulosic ethanol technology can be tracked. With an assumed feedstock cost for corn stover of $58.50/ton this target has historically been set at $1.41/gal ethanol for conversion costs only (exclusive of feedstock) and $2.15/gal total production cost (inclusive of feedstock) or minimum ethanol selling price (MESP). This year, fully integrated cellulosic ethanol production data generated by National Renewable Energy Laboratory (NREL) researchers in their Integrated Biorefinery Research Facility (IBRF) successfully demonstrated performance commensurate with both the FY 2012 SOT MESP target of $2.15/gal (2007$, $58.50/ton feedstock cost) and the conversion target of $1.41/gal through core research and process improvements in pretreatment, enzymatic hydrolysis, and fermentation.

  5. Influence of enzymatic hydrolysis and enzyme type on the nutritional and antioxidant properties of pumpkin meal hydrolysates.

    Science.gov (United States)

    Venuste, Muhamyankaka; Zhang, Xiaoming; Shoemaker, Charles F; Karangwa, Eric; Abbas, Shabbar; Kamdem, Patrick Eugene

    2013-04-30

    Nutritional and antioxidant properties of pumpkin meal and their hydrolysates prepared by hydrolysis with alcalase, flavourzyme, protamex or neutrase were evaluated. The hydrolysis process significantly increased protein content from 67.07% to 92.22%. All the essential amino acids met the Food and Agriculture Organization of United Nations/World Health Organization (WHO/FAO) suggested requirements for children and adults. The amino acid score (AAS) of meal was increased from 65.59 to 73.00 except for flavourzyme (62.97) and protamex (62.50). The Biological Value (BV) was increased from 53.18 to 83.44 except for protamex (40.97). However hydrolysis decreased the Essential Amino Acid/Total Amino Acid ratio (EAA/TAA) from 32.98% to 29.43%. Protein Efficiency Ratio (PER) was comparable to that of good quality protein (1.5) except for flavourzyme hydrolysate which had PER1 = 0.92, PER2 = 1.03, PER3 = 0.38. The in vitro protein digestibility (IVPD) increased from 71.32% to 77.96%. Antioxidant activity increased in a dose-dependent manner. At 10 mg mL(-1), the hydrolysates had increased 1,1-diphenyl-2-picrylhydrazy (DPPH) radical scavenging activities from 21.89% to 85.27%, the reducing power increased from Abs(700nm) 0.21 to 0.48. Metal (Iron) chelating ability was improved from 30.50% to 80.03% at 1 mg mL(-1). Hydrolysates also showed better capabilities to suppress or delay lipid peroxidation in a linoleic acid model system. Different proteases lead to different Degrees of Hydrolysis (DH), molecular weight (MW) distribution, amino acid composition and sequence, which influenced the nutritional properties and antioxidant activities of the hydrolysates. Alcalase was the most promising protease in production of pumpkin protein hydrolysates with improved nutritional quality, while flavourzyme was best in production of hydrolysates with improved antioxidative activity among various assays. These results showed that hydrolysates from by-products of pumpkin oil-processing

  6. Membrane bioreactors for enzymatic hydrolysis of lactose; Idrolisi enzimatica del lattosio con bioreattori a membrana

    Energy Technology Data Exchange (ETDEWEB)

    Pizzichini, M; Pilloton, R [ENEA, Casaccia (Italy). Area Energia e Innovazione; Pontecorvo, M; Mignogna, G; Fortunato, A; Beone, F

    1993-03-01

    Bioreactor systems obtained by cell or enzyme immobilization offer many advantages compared with native enzyme, intact cell systems or other biocatalysts. Thus, many attempts have been made to design and use new types of bioreactor systems in order to improve performance, enhance productivity and reduce environmental impacts. Membrane bioreactors, obtained by physical immobilization of biocatalysts, in polymeric membrane support, offer such practical advantages as: a continuous separation and transformation process with low product inhibition and suitable hydraulic configuration (backflushing recycling, ultrafiltrating). Specific membrane modules (Amicon VitaFiber), for bioreactor applications are being commercialized. Beta-galctosidase enzyme has successfully been immobilized in a hollow fiber and in ceramic modules to hydrolyze lactose in waste whey. This technical report presents the general properties and performances (permeability, washing procedures, hydraulic configurations, physical and chemical properties) of both, polymeric and ceramic supports, enzyme kinetics, physical and covalent immobilization, mathematical model of the bioreactor and on-line process monitoring.

  7. Free energy diagram for the heterogeneous enzymatic hydrolysis of glycosidic bonds in cellulose

    DEFF Research Database (Denmark)

    Westh, Peter; Cruys-Bagger, Nicolaj; Sørensen, Trine Holst

    2015-01-01

    for all stable and activated complexes defined by the reaction scheme, and hence propose a free energy diagram for the full heterogeneous process. For other Cel7A enzymes, including variants with and without carbohydrate binding module (CBM), we obtained activation parameters for the association...... no influence on the transition state for association, but increased the free energy barrier for dissociation. Hence, the CBM appeared to promote the stability of the complex by delaying dissociation rather than accelerating association....

  8. Ultrasound assisted enzymatic hydrolysis for isolating titanium dioxide nanoparticles from bivalve mollusk before sp-ICP-MS.

    Science.gov (United States)

    Taboada-López, María Vanesa; Iglesias-López, Sara; Herbello-Hermelo, Paloma; Bermejo-Barrera, Pilar; Moreda-Piñeiro, Antonio

    2018-08-14

    Applicability of single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) using dwell times equal to or shorter than 100 μs has been tested for assessing titanium dioxide nanoparticles (TiO 2 NPs) in bivalve mollusks. TiO 2 NPs isolation from fresh mollusk tissues was achieved by ultrasound assisted enzymatic hydrolysis procedure using a pancreatin/lipase mixture. Optimum extraction conditions imply ultrasonication (60% amplitude) for 10 min, and 7.5 mL of a solution containing 3.0 g L -1 of pancreatin and lipase (pH 7.4). The developed method was found to be repeatable (repeatability of 17% for the over-all procedure, TiO 2 NPs concentration of 5.33 × 10 7  ± 8.89 × 10 6 , n = 11), showing a limit of detection of 5.28 × 10 6 NPs g -1 , and a limit of detection in size of 24.4-30.4 nm, based on the 3σ criteria, and on the 3σ/5 σ criteria, respectively. The analytical recovery within the 90-99% range (use of TiO 2 NPs standards of 50 nm at 7 and 14 μg L -1 as Ti). Several bivalve mollusks (clams, cockles, mussels, razor clams, oysters and variegated scallops) were analyzed for total titanium (ICP-MS after microwave assisted acid digestion), and for TiO 2 NPs by the proposed method. TiO 2 NPs concentrations were within the 2.36 × 10 7 -1.25 × 10 8 NPs g -1 range, and the most frequent sizes were from 50 to 70 nm. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. The effect of amphipilic lignin derivatives addition on enzymatic hydrolysis performance of kraft pulp from sorghum bagasse

    Science.gov (United States)

    Fatriasari, Widya; Nugroho Adi, D. T.; Laksana, R. P. B.; Fajriutami, T.; Raniya, R.; Ghozali, M.; Hermiati, E.

    2018-03-01

    Previously, the chemical characteristics of isolated lignin from Acacia mangium black liquor of kraft pulping was characterized. This lignin was blended with natural rubber latex (NR-L) as adhesive in laminated wood. In addition, lignin has potency for biosurfactant materials by modification of the hydrophobic into hydrophilic properties. Therefore, this study was intended to develop lignin as material for amphipilic lignin derivatives (A-LD) biosurfactant by reacting lignin with epoxilated polyethylene glicol (PEG). A-LD addition in slurries was used to improve the enzymatic hydrolysis (EH) of kraft pulp sweet bagasse sorghum (SSB). The main observation in EH performance was to investigate the effect of lignin isolation method (one and two step) in A-LD and A-LD loading addition on reducing sugar yield (RSY) of SSB kraft pulp. The pulp was hydrolyzed at 50°C and 150 rpm for 72 h with 10 FPU cellulase loading in the shaking incubator. A-LD from one (L1S) and two step (L2S) lignin was added with A-LD loading of 0, 1, 2, 5, and 10% (b/v). The RSY of hydrolyzate has been observed after EH. A-LDs addition in EH of SSB kraft pulp enhanced RSY. L1S worked better in reaction performance with PEDGE compared to L2S and LS. A better performance was showed by PEDGE 500 than that of PEDGE 6000. Generally, the higher A-LDs loading resulted higher RSY. The highest RSY (81.33%) was resulted in addition of 10% A-LD L1S using PEDGE 500. A 5% A-LD loading was more considered to be added in EH because the RSY was comparable with 10% A-LD loading.

  10. The enhancement of enzymatic hydrolysis of lignocellulosic substrates by the addition of accessory enzymes such as xylanase: is it an additive or synergistic effect?

    Directory of Open Access Journals (Sweden)

    Saddler Jack N

    2011-10-01

    Full Text Available Abstract Background We and other workers have shown that accessory enzymes, such as β-glucosidase, xylanase, and cellulase cofactors, such as GH61, can considerably enhance the hydrolysis effectiveness of cellulase cocktails when added to pretreated lignocellulosic substrates. It is generally acknowledged that, among the several factors that hamper our current ability to attain efficient lignocellulosic biomass conversion yields at low enzyme loadings, a major problem lies in our incomplete understanding of the cooperative action of the different enzymes acting on pretreated lignocellulosic substrates. Results The reported work assessed the interaction between cellulase and xylanase enzymes and their potential to improve the hydrolysis efficiency of various pretreated lignocellulosic substrates when added at low protein loadings. When xylanases were added to the minimum amount of cellulase enzymes required to achieve 70% cellulose hydrolysis of steam pretreated corn stover (SPCS, or used to partially replace the equivalent cellulase dose, both approaches resulted in enhanced enzymatic hydrolysis. However, the xylanase supplementation approach increased the total protein loading required to achieve significant improvements in hydrolysis (an additive effect, whereas the partial replacement of cellulases with xylanase resulted in similar improvements in hydrolysis without increasing enzyme loading (a synergistic effect. The enhancement resulting from xylanase-aided synergism was higher when enzymes were added simultaneously at the beginning of hydrolysis. This co-hydrolysis of the xylan also influenced the gross fiber characteristics (for example, fiber swelling resulting in increased accessibility of the cellulose to the cellulase enzymes. These apparent increases in accessibility enhanced the steam pretreated corn stover digestibility, resulting in three times faster cellulose and xylan hydrolysis, a seven-fold decrease in cellulase loading and

  11. A pyranose dehydrogenase-based biosensor for kinetic analysis of enzymatic hydrolysis of cellulose by cellulases

    DEFF Research Database (Denmark)

    Cruys-Bagger, Nicolaj; Badino, Silke Flindt; Tokin, Radina Naytchova

    2014-01-01

    A novel electrochemical enzyme biosensor was developed for real-time detection of cellulase activity when acting on their natural insoluble substrate, cellulose. The enzyme biosensor was constructed with pyranose dehydrongease (PDH) from Agaricus meleagris that was immobilized on the surface......-biosensor was shown to be anomer unspecific and it can therefore be used in kinetic studies over broad time-scales of both retaining- and inverting cellulases (in addition to enzyme cocktails). The biosensor was used for real-time measurements of the activity of the inverting cellobiohydrolase Cel6A from Hypocrea...... equation for processive cellulases, and it was found that the turnover for HjCel6A at saturating substrate concentration (i.e. maximal apparent specific activity) was similar (0.39–0.40 s−1) for the two substrates. Conversely, the substrate load at half-saturation was much lower for BMCC compared to Avicel...

  12. Enzymatic hydrolysis of eucalyptus biomass for bioethanol production: a bibliometric analysis

    Directory of Open Access Journals (Sweden)

    Renan Amorim Margon

    2018-04-01

    Full Text Available The energy matrix in the Brazilian and world scenarios has undergone significant changes during the last decades. Due to oscillations in the price of the oil barrel and its derivatives, the study of alternative energies has been intensifying. In this context, the production of second generation bioethanol has been considered as a way to meet this demand. Besides being able to partially solve the dependence of the use of fossil fuels, this technology stands out for utilizing lignocellulosic industries residues, adding value to this material. This article consists of a bibliometric review of this application, giving an overview of the advances made to date. A quantitative analysis of the articles found in the Web of Science database was carried out, followed by a qualitative analysis. Subsequently, the convergences and divergences between the articles were identified. The results demonstrate that some improvements are still needed in the process, however the technique is feasible and advantageous in the production of bioethanol.

  13. Optimization of dynamic-microwave assisted enzymatic hydrolysis extraction of total ginsenosides from stems and leaves of panax ginseng by response surface methodology.

    Science.gov (United States)

    Wang, Xiao-Yan; Ren, Hui

    2018-03-21

    Ginseng stems and leaves (GSAL) are abundant in ginsenosides compounds. For efficient utilization of GSAL and the enhancement of total ginsenosides (TG) compound yields in GSAL, TG from GSAL were extracted, using dynamic-microwave assisted extraction coupled with enzymatic hydrolysis (DMAE-EH) method. The extraction process has been simulated and its main influencing factors such as ethanol concentration, microwave temperature, microwave time and pump flow rate have been optimized by response surface methodology coupled with a Box-Behnken design(BBD). The experimental results indicated that optimal extraction conditions of TG from GSAL were as follows: ethanol concentration of 75%, microwave temperature of 60°C, microwave time of 20 min and pump flow rate of 38 r/min. After experimental verification, the experimental yields of TG was 60.62 ± 0.85 mg g -1 , which were well agreement with the predicted by the model. In general, the present results demonstrated that DMAE-EH method was successfully used to extract total ginsenosides in GSAL.

  14. Enzymatic surface hydrolysis of polyamide 6,6 with mixtures of proteolytic and lipolytic enzymes.

    Science.gov (United States)

    Parvinzadeh Gashti, Mazeyar; Assefipour, Reza; Kiumarsi, Amir; Parvinzadeh Gashti, Mahyar

    2013-01-01

    This study investigated the changes induced on nylon 6,6 fabric by a mixture of proteolytic and lipolytic enzymes. Technical measurements were studied including those of Fourier-transform infrared spectroscopy (FTIR), thermal gravimetric analysis (TGA), weight loss (WL), bending lengths (BL), scanning electron microscopy (SEM), moisture absorbency (MA), and reflectance spectroscopy (RS). For this purpose, nylon 6,6 fabrics were treated separately with different concentrations of protease and lipase mixtures in solution. The dyeing process was then carried out on the treated fabrics with two reactive and acid dyes. The intensity of major peaks in the FTIR spectra of the protease-treated samples is in favor of chemical changes the polypeptide functional groups in the fabrics. Thermal studies also show a significant decrease in the thermal degradation temperature of the treated polymer at temperatures higher than 400°C. The protease and lipase mixtures decreased the sample weight, while lipase intensified the weight loss comparing with protease. It was observed that the concentration of lipase enzyme had a direct influence on the darkness of dyed samples.

  15. Enzymatic cell disruption of microalgae biomass in biorefinery processes.

    Science.gov (United States)

    Demuez, Marie; Mahdy, Ahmed; Tomás-Pejó, Elia; González-Fernández, Cristina; Ballesteros, Mercedes

    2015-10-01

    When employing biotechnological processes for the procurement of biofuels and bio-products from microalgae, one of the most critical steps affecting economy and yields is the "cell disruption" stage. Currently, enzymatic cell disruption has delivered effective and cost competitive results when compared to mechanical and chemical cell disruption methods. However, the introduction of enzymes implies additional associated cost within the overall process. In order to reduce this cost, autolysis of microalgae is proposed as alternative enzymatic cell disruption method. This review aims to provide the state of the art of enzymatic cell disruption treatments employed in biorefinery processes and highlights the use of endopeptidases. During the enzymatic processes of microalgae life cycle, some lytic enzymes involved in cell division and programmed cell death have been proven useful in performing cell lysis. In this context, the role of endopeptidases is emphasized. Mirroring these natural events, an alternative cell disruption approach is proposed and described with the potential to induce the autolysis process using intrinsic cell enzymes. Integrating induced autolysis within biofuel production processes offers a promising approach to reduce overall global costs and energetic input associated with those of current cell disruption methods. A number of options for further inquiry are also discussed. © 2015 Wiley Periodicals, Inc.

  16. Enzymatic Hydrolysis of Lignocelluloses

    DEFF Research Database (Denmark)

    Kolasa, Marta; Ahring, Birgitte Kiær; Lübeck, Peter Stephensen

    2010-01-01

    source. By means of degenerate PCR, specific genes, homologous to the genes of previously classified glycoside hydrolases from CAZY database, are searched for in selected strains of Aspergillus sp., Trichoderma sp. and Penicillium sp. Both methods are anticipated to facilitate identification of target...

  17. Industrial-scale steam explosion pretreatment of sugarcane straw for enzymatic hydrolysis of cellulose for production of second generation ethanol and value-added products.

    Science.gov (United States)

    Oliveira, Fernando M V; Pinheiro, Irapuan O; Souto-Maior, Ana M; Martin, Carlos; Gonçalves, Adilson R; Rocha, George J M

    2013-02-01

    Steam explosion at 180, 190 and 200°C for 15min was applied to sugarcane straw in an industrial sugar/ethanol reactor (2.5m(3)). The pretreated straw was delignificated by sodium hydroxide and hydrolyzed with cellulases, or submitted directly to enzymatic hydrolysis after the pretreatment. The pretreatments led to remarkable hemicellulose solubilization, with the maximum (92.7%) for pretreatment performed at 200°C. Alkaline treatment of the pretreated materials led to lignin solubilization of 86.7% at 180°C, and only to 81.3% in the material pretreated at 200°C. All pretreatment conditions led to high hydrolysis conversion of cellulose, with the maximum (80.0%) achieved at 200°C. Delignification increase the enzymatic conversion (from 58.8% in the cellulignin to 85.1% in the delignificated pulp) of the material pretreated at 180°C, but for the material pretreated at 190°C, the improvement was less remarkable, while for the pretreated at 200°C the hydrolysis conversion decreased after the alkaline treatment. Copyright © 2012 Elsevier Ltd. All rights reserved.

  18. Moving towards a Competitive Fully Enzymatic Biodiesel Process

    Directory of Open Access Journals (Sweden)

    Silvia Cesarini

    2015-06-01

    Full Text Available Enzymatic biodiesel synthesis can solve several problems posed by the alkaline-catalyzed transesterification but it has the drawback of being too expensive to be considered competitive. Costs can be reduced by lipase improvement, use of unrefined oils, evaluation of soluble/immobilized lipase preparations, and by combination of phospholipases with a soluble lipase for biodiesel production in a single step. As shown here, convenient natural tools have been developed that allow synthesis of high quality FAMEs (EN14214 from unrefined oils in a completely enzymatic single-step process, making it fully competitive.

  19. Integrating Porous Resins In Enzymatic Processes

    DEFF Research Database (Denmark)

    Al-Haque, Naweed

    . Screening resins for moderately hydrophobic multi-component systems is challenging. Often it is found that the capacity of the resin is inversely related with product selectivity. Therefore a tradeoff has to be made between these parameters which can be crucial from an economic point of view. A low resin...... procedure. The screening therefore becomes a multi-objective task that has to be solved simultaneously. Such an approach has been applied in the method formulated in this framework. To overcome these challenges, different process strategies are required to obtain high yields. A number of different...... inhibition, has gained considerable recognition. The resins act as a reservoir for the inhibitory substrate and a sink for the inhibitory product and simultaneously attain the required high substrate loading to make the process economically feasible. In this way the potential benefit of the enzyme can...

  20. Enzymatic biodiesel synthesis. Key factors affecting efficiency of the process

    Energy Technology Data Exchange (ETDEWEB)

    Szczesna Antczak, Miroslawa; Kubiak, Aneta; Antczak, Tadeusz; Bielecki, Stanislaw [Institute of Technical Biochemistry, Faculty of Biotechnology and Food Sciences, Technical University of Lodz, Stefanowskiego 4/10, 90-924 Lodz (Poland)

    2009-05-15

    Chemical processes of biodiesel production are energy-consuming and generate undesirable by-products such as soaps and polymeric pigments that retard separation of pure methyl or ethyl esters of fatty acids from glycerol and di- and monoacylglycerols. Enzymatic, lipase-catalyzed biodiesel synthesis has no such drawbacks. Comprehension of the latter process and an appreciable progress in production of robust preparations of lipases may soon result in the replacement of chemical catalysts with enzymes in biodiesel synthesis. Engineering of enzymatic biodiesel synthesis processes requires optimization of such factors as: molar ratio of substrates (triacylglycerols: alcohol), temperature, type of organic solvent (if any) and water activity. All of them are correlated with properties of lipase preparation. This paper reports on the interplay between the crucial parameters of the lipase-catalyzed reactions carried out in non-aqueous systems and the yield of biodiesel synthesis. (author)

  1. Analytical Characterization of the Hydrolysis of Barley Malt Macromolecules During Enzymatic Degradation Over Time Using AF4/MALS/RI.

    Science.gov (United States)

    Rübsam, Heinrich; Becker, Thomas; Gastl, Martina

    2017-06-01

    The changes on the molecular weight distribution (MWD) and particle size distribution (PSD) during hydrolysis of barley malt in isothermal mashing procedures were determined using asymmetrical flow field flow fractionation coupled to multiangle laser light scattering and refractive index (AF4/MALS/RI). Mash/trials were focused on amylolytic starch degradation. Therefore, temperatures (65, 70, and 75 °C) were selected according to α- and β-amylases range of activity. Samples were produced by triplicate, tracking amylolytic processes over time periods from 10 to 90 min in each mash/trial. AF4/MALS/RI analysis demonstrated significant differences on the values of the MWD and PSD according to the temperature/time profile used. At mashing times over 30 min at a temperature of 65 °C, when α- and β-amylase are both active, the decrease over time of the MWD and PSD was significantly higher (P < 0.005) than at 70 °C when mainly α-amylase is active. At 75 °C, also the activity of α-amylase decreased and the MWD and PSD were significantly lower (P < 0.005) than at 70 or 65 °C at any time of the procedure. The MWD and PSD of beer components influence beer palate fullness, thus AF4/ MALS/RI would be a powerful tool for breweries to adapt their technological processes to obtain beers with particular sensorial attributes. © 2017 Institute of Food Technologists®.

  2. Hidrólise enzimática de casca de arroz utilizando-se celulases: efeito de tratamentos químicos e fotoquímicos Enzymatic hydrolysis of rice hull using cellulases: effect of chemical and photochemical treatments

    Directory of Open Access Journals (Sweden)

    Juan Reyes

    1998-04-01

    Full Text Available In the present work we reported the study of rice hull enzymatic hydrolysis using a commercial cellulase preparation. The results showed that previous treatment with light and sodium chlorite inhibits the enzymatic process (31.4 and 11.8%, respectively while hydrogen peroxide and ozone favoured the enzymatic production of reducing sugars (5.9 and 54.9%, respectively. Studies performed by quimiluminescence showed that the chlorite treatment produced the most significant change in the structure of rice hull. Nevertheless, this treatment did not favour the subsequent enzymatic process. Photomicrographs obtained from rice hull hydrolysates showed that pre-treatment changed mainly the inner epidermis and parenchyma cell and that they did not change cellular organization of the hull.

  3. Effects of processing conditions on hydrolysis of cassava starch ...

    African Journals Online (AJOL)

    amyloglucosidase using 30% initial cassava starch concentration, which produced 152 g/l reducing sugar concentration and DE of 50.9. The total effective operating time was 60 h. Keywords:Cassava starch, hydrolysis, enzyme, dextrose equivalent.

  4. Effect of pretreatment severity on accumulation of major degradation products from dilute acid pretreated corn stover and subsequent inhibition of enzymatic hydrolysis of cellulose.

    Science.gov (United States)

    Um, Byung-Hwan; van Walsum, G Peter

    2012-09-01

    The concept of reaction severity, which combines residence time and temperature, is often used in the pulp and paper and biorefining industries. The influence of corn stover pretreatment severity on yield of sugar and major degradation products and subsequent effects on enzymatic cellulose hydrolysis was investigated. The pretreatment residence time and temperature, combined into the severity factor (Log R(o)), were varied with constant acid concentration. With increasing severity, increasing concentrations of furfural and 5-hydroxymethylfurfural (5-HMF) coincided with decreasing yields of oligosaccharides. With further increase in severity factor, the concentrations of furans decreased, while the formation of formic acid and lactic acid increased. For example, from severity 3.87 to 4.32, xylose decreased from 6.39 to 5.26 mg/mL, while furfural increased from 1.04 to 1.33 mg/mL; as the severity was further increased to 4.42, furfural diminished to 1.23 mg/mL as formate rose from 0.62 to 1.83 mg/mL. The effects of dilute acid hydrolyzate, acetic acid, and lignin, in particular, on enzymatic hydrolysis were investigated with a rapid microassay method. The microplate method gave considerable time and cost savings compared to the traditional assay protocol, and it is applicable to a broad range of lignocellulosic substrates.

  5. Solar assisted alkali pretreatment of garden biomass: Effects on lignocellulose degradation, enzymatic hydrolysis, crystallinity and ultra-structural changes in lignocellulose

    International Nuclear Information System (INIS)

    Gabhane, Jagdish; William, S.P.M. Prince; Vaidya, Atul N.; Das, Sera; Wate, Satish R.

    2015-01-01

    Highlights: • SAAP is an efficient and economic means of pretreatment. • SAAP was found to be efficient in lignin and hemicellulose removal. • SAAP enhanced the enzymatic hydrolysis. • FTIR, XRD and SEM provided vivid understanding about the mode of action of SAAP. • Mass balance closer of 98% for pretreated GB confirmed the reliability of SAAP. - Abstract: A comprehensive study was carried out to assess the effectiveness of solar assisted alkali pretreatment (SAAP) on garden biomass (GB). The pretreatment efficiency was assessed based on lignocellulose degradation, conversion of cellulose into reducing sugars, changes in the ultra-structure and functional groups of lignocellulose and impact on the crystallinity of cellulose, etc. SAAP was found to be efficient for the removal of lignin and hemicellulose that facilitated enzymatic hydrolysis of cellulose. FTIR and XRD studies provided details on the effectiveness of SAAP on lignocellulosic moiety and crystallinity of cellulose. Scanning electron microscopic analysis showed ultra-structural disturbances in the microfibrils of GB as a result of pretreatment. The mass balance closer of 97.87% after pretreatment confirmed the reliability of SAAP pretreatment. Based on the results, it is concluded that SAAP is not only an efficient means of pretreatment but also economical as it involved no energy expenditure for heat generation during pretreatment

  6. ENZYMATIC HYDROLYSIS LIGNIN DERIVED FROM CORN STOVER AS AN INTRINSTIC BINDER FOR BIO-COMPOSITES MANUFACTURE: EFFECT OF FIBER MOISTURE CONTENT AND PRESSING TEMPERATURE ON BOARDS’ PROPERTIES

    Directory of Open Access Journals (Sweden)

    Guanben Du

    2011-02-01

    Full Text Available Binderless fiberboards from enzymatic hydrolysis lignin (EHL and cotton stalk fibers were prepared under various manufacturing conditions, and their physico-mechanical properties were evaluated. Full factorial experimental design was used to assess the effect of fiber moisture content and pressing temperature on boards’ properties. In addition, differential scanning calorimetry (DSC was used to obtain the glass transition temperature (Tg of EHL. We found that both fiber moisture content and pressing temperature had significant effects on binderless fiberboards’ properties. High fiber moisture content and pressing temperature are suggested to contribute to the self-bonding improvement among fibers with lignin-rich surface mainly by thermal softening enzymatic hydrolysis lignin. In this experiment, the optimized pressing temperature applied in binderless fiberboard production should be as high as 190°C in accordance with the EHL Tg value of 189.4°C, and the fiber moisture content should be limited to less than 20% with a higher board density of 950 kg/m3 to avoid the delamination of boards during hot pressing.

  7. Towards an optimal process for gelatinisation and hydrolysis of highly concentrated starch-water mixtures with alpha-amylase from B. licheniformis

    NARCIS (Netherlands)

    Baks, T.; Kappen, F.H.J.; Janssen, A.E.M.; Boom, R.M.

    2008-01-01

    The enzymatic hydrolysis of starch is usually carried out with 30¿35 w/w% starch in water. Higher substrate concentrations (50¿70 w/w%) were reached by using a twin-screw extruder for gelatinisation and for mixing enzyme with gelatinised starch prior to enzymatic hydrolysis in a batch reactor. The

  8. Process Evaluation Tools for Enzymatic Cascades Welcome Message

    DEFF Research Database (Denmark)

    Abu, Rohana

    improvement and implementation. Hence, the goal of this thesis is to evaluate the process concepts in enzymatic cascades in a systematic manner, using tools such as thermodynamic and kinetic analysis. Three relevant case studies have been used to exemplify the approach. In the first case study, thermodynamic......Biocatalysis is attracting significant attention from both academic and industrial scientists due to the excellent capability of enzyme to catalyse selective reactions. Recently, much interest has been shown in the application of enzymatic cascades as a useful tool in organic synthesis......, the kinetics can be controlled in a highly efficient way to achieve a sufficiently favourable conversion to a given target product. This is exemplified in the second case study, in the kinetic modelling of the formation of 2-ketoglutarate from glucoronate, the second case study. This cascade consists of 4...

  9. Processes and modeling of hydrolysis of particulate organic matter in aerobic wastewater tratment - A review

    DEFF Research Database (Denmark)

    Morgenroth, Eberhard Friedrich; Kommedal, Roald; Harremoës, Poul

    2002-01-01

    Carbon cycling and the availability of organic carbon for nutrient removal processes are in most wastewater treatment systems restricted by the rate of hydrolysis of slowly biodegradable (particulate) organic matter. To date, the mechanisms of hydrolysis are not well understood for complex...

  10. Enhanced sugar production from pretreated barley straw by additive xylanase and surfactants in enzymatic hydrolysis for acetone-butanol-ethanol fermentation.

    Science.gov (United States)

    Yang, Ming; Zhang, Junhua; Kuittinen, Suvi; Vepsäläinen, Jouko; Soininen, Pasi; Keinänen, Markku; Pappinen, Ari

    2015-01-01

    This study aims to improve enzymatic sugar production from dilute sulfuric acid-pretreated barley straw for acetone-butanol-ethanol (ABE) fermentation. The effects of additive xylanase and surfactants (polyethylene glycol [PEG] and Tween) in an enzymatic reaction system on straw hydrolysis yields were investigated. By combined application of 2g/100g dry-matter (DM) xylanase and PEG 4000, the glucose yield was increased from 53.2% to 86.9% and the xylose yield was increased from 36.2% to 70.2%, which were considerably higher than results obtained with xylanase or surfactant alone. The ABE fermentation of enzymatic hydrolysate produced 10.8 g/L ABE, in which 7.9 g/L was butanol. The enhanced sugar production increased the ABE yield from 93.8 to 135.0 g/kg pretreated straw. The combined application of xylanase and surfactants has a large potential to improve sugar production from barley straw pretreated with a mild acid and that the hydrolysate showed good fermentability in ABE production. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Conversion of Cassava Starch to Produce Glucose and Fructose by Enzymatic Process Using Microwave Heating

    Directory of Open Access Journals (Sweden)

    Sumardiono Siswo

    2018-01-01

    Full Text Available In this study, variation of glycosidase enzyme concentration and saccharification time on enzymatic hydrolysis using microwave have been investigated. Concentration and kinetic parameters rate of glucose and fructose were analyzed. Cassava starch was liquefied and gelatinized by microwave at 80°C. The gelatinized starch was saccharified at 60°C using (0.2;0.4;0.6;0.8;1% (w/v glycosidase enzyme for 24, 48 and 72 hours. The glucose which has been saccharified with 1% glycosidase enzyme for 72 hours gave highest conversion 66.23 %. The optimization process by multilevel reaction gave the highest conversion at enzyme concentrations 0.88 %and saccharification time 29 hours that 68.82%. The highest conversion of glucose was isomerized to fructose. The fructose which has been isomerized for 180 minutes gave highest conversion 20.05 %. The kinetics enzymatic reaction was approached and determined by Michaelis - Menten equation, Km and Vmax of reaction for glucose 22.94 g/L; 2.70 g/L hours and for fructose 3.39 g/L; 0.38 g/L. min respectively.

  12. The Effect of Sugarcane Bagassès Size on the Properties of Pretreatment and Enzymatic Hydrolysis

    Science.gov (United States)

    Xu, Jun; Zhou, Guoqiang; Li, Jun

    2017-06-01

    The influence of milled bagasse particle size on their reducing sugar and lignin content during dilute acid hydrolysis followed by enzymolysis was investigated. The biomass crystal structures of hydrolyzed residues and enzymolyzed substrates were studied with X-ray diffractometry (XRD). The results showed that the conversion ratio of reducing sugar declined with decreasing milled bagasse particle size. The conversion ratio of reducing sugar after acid hydrolysis decreased from 31.3% to 28.9%. The smaller of the milled bagasse particle size was, the higher of the klason lignin content of hydrolyzed residuals was, which resulted in a decline in conversion ratio of reducing sugar during enzymolysis. In this study, the optimal size of milled bagasse particles was 10 to 20 meshes. The total reducing sugar conversion ratio was 61.5%, consisting of 31.3% in hydrolysis and 30.2% in enzymolysis. After hydrolysis, the specific surface area and pore size increased, and the fiber length was shortened. The inner microfiber bundles were exposed, which improved the accessibility of cellulase and the efficiency of enzymolysis.

  13. A process for producing lignin and volatile compounds from hydrolysis liquor.

    Science.gov (United States)

    Khazraie, Tooran; Zhang, Yiqian; Tarasov, Dmitry; Gao, Weijue; Price, Jacquelyn; DeMartini, Nikolai; Hupa, Leena; Fatehi, Pedram

    2017-01-01

    Hot water hydrolysis process is commercially applied for treating wood chips prior to pulping or wood pellet production, while it produces hydrolysis liquor as a by-product. Since the hydrolysis liquor is dilute, the production of value-added materials from it would be challenging. In this study, acidification was proposed as a viable method to extract (1) furfural and acetic acid from hot water hydrolysis liquor and (2) lignin compounds from the liquor. The thermal properties of the precipitates made from the acidification of hydrolysis liquor confirmed the volatile characteristics of precipitates. Membrane dialysis was effective in removing inorganic salts associated with lignin compounds. The purified lignin compounds had a glass transition temperature (Tg) of 180-190 °C, and were thermally stable. The results confirmed that lignin compounds present in hot water hydrolysis liquor had different characteristics. The acidification of hydrolysis liquor primarily removed the volatile compounds from hydrolysis liquor. Based on these results, a process for producing purified lignin and precipitates of volatile compounds was proposed.

  14. Deposition of lignin droplets produced during dilute acid pretreatment of maize stems retards enzymatic hydrolysis of cellulose.

    Science.gov (United States)

    Selig, Michael J; Viamajala, Sridhar; Decker, Stephen R; Tucker, Melvin P; Himmel, Michael E; Vinzant, Todd B

    2007-01-01

    Electron microscopy of lignocellulosic biomass following high-temperature pretreatment revealed the presence of spherical formations on the surface of the residual biomass. The hypothesis that these droplet formations are composed of lignins and possible lignin carbohydrate complexes is being explored. Experiments were conducted to better understand the formation of these "lignin" droplets and the possible implications they might have on the enzymatic saccharification of pretreated biomass. It was demonstrated that these droplets are produced from corn stover during pretreatment under neutral and acidic pH at and above 130 degrees C, and that they can deposit back onto the surface of residual biomass. The deposition of droplets produced under certain pretreatment conditions (acidic pH; T > 150 degrees C) and captured onto pure cellulose was shown to have a negative effect (5-20%) on the enzymatic saccharification of this substrate. It was noted that droplet density (per unit area) was greater and droplet size more variable under conditions where the greatest impact on enzymatic cellulose conversion was observed. These results indicate that this phenomenon has the potential to adversely affect the efficiency of enzymatic conversion in a lignocellulosic biorefinery.

  15. The effect of harvest time, dry matter content and mechanical pretreatments on anaerobic digestion and enzymatic hydrolysis of miscanthus

    DEFF Research Database (Denmark)

    Nielsen, Susanne Frydendal; Hjorth, Maibritt; Baby, Sanmohan

    2016-01-01

    -milling, extrusion or grinding and accumulated methane production and enzymatically-accessible sugars were measured. Accumulated methane production was studied using sigmoid curves that allowed comparison among the treatments of the rate of the methane production and ultimate methane yield. The green biomass gave...

  16. Chapter 2.1 Integrated Production of Cellulose Nanofibrils and Cellulosic Biofuel by Enzymatic Hydrolysis of wood Fibers

    Science.gov (United States)

    Ronald Sabo; J.Y. Zhu

    2013-01-01

    One key barrier to converting woody biomass to biofuel through the sugar platform is the low efficiency of enzymatic cellulose saccharification due to the strong recalcitrance of the crystalline cellulose. Significant past research efforts in cellulosic biofuels have focused on overcoming the recalcitrance of lignocelluloses to enhance the saccharification of...

  17. Enzymatic hydrolysis of 1-monoacyl-SN-glycerol-3-phosphoryl-choline (1-lysolecithin) by phospholipases from peanut seeds.

    Science.gov (United States)

    Strauss, H; Leibovitz-Ben Gershon, Z; Heller, M

    1976-06-01

    Hydrolysis of 1-lysolecithin (1-acyl glycerophosphorylcholine [1-acyl GPC]) by preparations of phospholipase D from peanut seeds was investigated. 1-Lysolecithin was hydrolyzed at a much slower rate than phosphatidylcholine (lecithin). Although Ca+2 ions are required for the cleavage of lecithin by the enzyme, their effect on the hydrolysis of lysolecithin depended upon the concentration of the substrate: at 0.2 mM 1-lysolecithin, Ca+2 ions increased the reaction rates, whereas at concentrations of the substrate lower than 0.1 mM, Ca+2 ions were inhibitory. A broad pH activity curve between 5 and 8 was obtained with higher rates in the alkaline range, both in the absence and presence of Ca+2 ions. The increased hydrolysis of lysolecithin due to Ca+2 was noticed over the entire pH range. Upon storage of the enzyme solutions at 4 C, decreased rates of hydrolysis of lecithin were observed, with t 1/2 values of ca. 50 and 100 days depending on the purity of the preparation. During the same period, no reduction occurred in the activity of these preparations on lysolecithin as substrate. The effects of Ca+2 ions and the analysis of the products of 1-acyl GPC cleavage by the enzyme preparations revealed the presence of more than one enzyme and the formation of the following compounds: lysophosphatidic acids (1 acyl glycerophosphoric acids), free fatty acids, glycerophosphorylcholine, and choline. The possible pathways leading to the degradation of lysolecithin and the formation of these products include reactions catalyzed by lysophospholipase A1 (lysophosphatidylcholine 1-acyl hydrolase, E.C. 3.1.1.5) and a phosphodiesterase (L-3-glycerylphosphorylcholine glycerophosphohydrolase, E.C.3.1.4.2), in addition to phospholipase D (phosphatidyl-choline phosphatidohydrolase, E.C. 3.1.4.4).

  18. High-loading-substrate enzymatic hydrolysis of palm plantation waste followed by unsterilized-mixed-culture fermentation for bio-ethanol production

    Science.gov (United States)

    Bardant, Teuku Beuna; Winarni, Ina; Sukmana, Hadid

    2017-01-01

    It was desired to obtain a general formula for producing bio-ethanol from any part of lignocelluloses wastes that came from palm oil industries due to its abundance. Optimum condition that obtained by using RSM for conducting high-loading-substrate enzymatic hydrolysis of palm oil empty fruit bunch was applied to palm oil trunks and then followed by unsterilized fermentation for producing bio-ethanol. From several optimized conditions investigated, the resulted ethanol concentration could reach 7.92 %v by using 36.5 %w of palm oil trunks but the results were averagely 2.46 %v lower than palm oil empty fruit bunch. The results was statistically compared and showed best correlative coefficient at 0.808 (in scale 0-1) which support the conclusion that the optimum condition for empty fruit bunch and trunks are similar. Utilization of mixed-culture yeast was investigated to produce ethanol from unsterilized hydrolysis product but the improvement wasn't significant compares to single culture yeast.

  19. Supplementation with xylanase and β-xylosidase to reduce xylo-oligomer and xylan inhibition of enzymatic hydrolysis of cellulose and pretreated corn stover

    Science.gov (United States)

    2011-01-01

    Background Hemicellulose is often credited with being one of the important physical barriers to enzymatic hydrolysis of cellulose, and acts by blocking enzyme access to the cellulose surface. In addition, our recent research has suggested that hemicelluloses, particularly in the form of xylan and its oligomers, can more strongly inhibit cellulase activity than do glucose and cellobiose. Removal of hemicelluloses or elimination of their negative effects can therefore become especially pivotal to achieving higher cellulose conversion with lower enzyme doses. Results In this study, cellulase was supplemented with xylanase and β-xylosidase to boost conversion of both cellulose and hemicellulose in pretreated biomass through conversion of xylan and xylo-oligomers to the less inhibitory xylose. Although addition of xylanase and β-xylosidase did not necessarily enhance Avicel hydrolysis, glucan conversions increased by 27% and 8% for corn stover pretreated with ammonia fiber expansion (AFEX) and dilute acid, respectively. In addition, adding hemicellulase several hours before adding cellulase was more beneficial than later addition, possibly as a result of a higher adsorption affinity of cellulase and xylanase to xylan than glucan. Conclusions This key finding elucidates a possible mechanism for cellulase inhibition by xylan and xylo-oligomers and emphasizes the need to optimize the enzyme formulation for each pretreated substrate. More research is needed to identify advanced enzyme systems designed to hydrolyze different substrates with maximum overall enzyme efficacy. PMID:21702938

  20. Supplementation with xylanase and β-xylosidase to reduce xylo-oligomer and xylan inhibition of enzymatic hydrolysis of cellulose and pretreated corn stover

    Directory of Open Access Journals (Sweden)

    Qing Qing

    2011-06-01

    Full Text Available Abstract Background Hemicellulose is often credited with being one of the important physical barriers to enzymatic hydrolysis of cellulose, and acts by blocking enzyme access to the cellulose surface. In addition, our recent research has suggested that hemicelluloses, particularly in the form of xylan and its oligomers, can more strongly inhibit cellulase activity than do glucose and cellobiose. Removal of hemicelluloses or elimination of their negative effects can therefore become especially pivotal to achieving higher cellulose conversion with lower enzyme doses. Results In this study, cellulase was supplemented with xylanase and β-xylosidase to boost conversion of both cellulose and hemicellulose in pretreated biomass through conversion of xylan and xylo-oligomers to the less inhibitory xylose. Although addition of xylanase and β-xylosidase did not necessarily enhance Avicel hydrolysis, glucan conversions increased by 27% and 8% for corn stover pretreated with ammonia fiber expansion (AFEX and dilute acid, respectively. In addition, adding hemicellulase several hours before adding cellulase was more beneficial than later addition, possibly as a result of a higher adsorption affinity of cellulase and xylanase to xylan than glucan. Conclusions This key finding elucidates a possible mechanism for cellulase inhibition by xylan and xylo-oligomers and emphasizes the need to optimize the enzyme formulation for each pretreated substrate. More research is needed to identify advanced enzyme systems designed to hydrolyze different substrates with maximum overall enzyme efficacy.

  1. Changes in the amino acid profiles and free radical scavenging activities of Tenebrio molitor larvae following enzymatic hydrolysis.

    Science.gov (United States)

    Tang, Yujiao; Debnath, Trishna; Choi, Eun-Ju; Kim, Young Wook; Ryu, Jung Pyo; Jang, Sejin; Chung, Sang Uk; Choi, Young-Jin; Kim, Eun-Kyung

    2018-01-01

    Tenebrio molitor (T. molitor) larvae provide food at low environmental cost and contribute positively to livelihoods. In this research, we compared the amino acids compositions and antioxidant activities of various extracts of T. molitor to enhance their quality as food. For the comparison, distilled water extracts, enzymatic hydrolysates, and condensed enzymatic hydrolysates of T. molitor larvae were prepared. Their amino acids (AAs) profiles and antioxidant activities, including ferric-reducing antioxidant power, oxygen radical absorption capacity, and DPPH, hydroxyl radical, and hydrogen peroxide radical scavenging properties assay were analyzed. DW extracts had the lowest AAs contents and antioxidant activity compared with enzymatic extracts. Condensed hydrolysates with a combination of alcalase and flavourzyme (C-A+F) exhibited the highest levels of total free AAs (11.1759 g/100 g). C-A+F produced higher total hydrolyzed AAs (32.5292 g/100 g) compared with the other groups. The C-A+F possessed the strongest antioxidant activity. Notably, the antioxidant activities of the hydrolysates and the total hydrolyzed AAs amount were correlated. Taken together, our findings showed that C-A+F was a promising technique for obtaining extracts of T. molitor larvae with antioxidant activity as potential nutritious functional food.

  2. Effect of enzymatic hydrolysis of starch on pasting, rheological and viscoelastic properties of milk-barnyard millet (Echinochloa frumentacea) blends meant for spray drying.

    Science.gov (United States)

    Kumar, P Arun; Pushpadass, Heartwin A; Franklin, Magdaline Eljeeva Emerald; Simha, H V Vikram; Nath, B Surendra

    2016-10-01

    The influence of enzymatic hydrolysis of starch on the pasting properties of barnyard millet was studied using a rheometer. The effects of blending hydrolyzed barnyard millet wort with milk at different ratios (0:1, 1:1, 1:1.5 and 1:2) on flow and viscoelastic behavior were investigated. From the pasting curves, it was evident that enzymatically-hydrolyzed starch did not exhibit typical pasting characteristics expected of normal starch. The Herschel-Bulkley model fitted well to the flow behaviour data, with coefficient of determination (R(2)) ranging from 0.942 to 0.988. All milk-wort blends demonstrated varying degree of shear thinning with flow behavior index (n) ranging from 0.252 to 0.647. Stress-strain data revealed that 1:1 blend of milk to wort had the highest storage modulus (7.09-20.06Pa) and an elastically-dominant behavior (phase angle <45°) over the tested frequency range. The crossover point of G' and G" shifted to higher frequencies with increasing wort content. From the flow and viscoelastic behavior, it was concluded that the 1:1 blend of milk to wort would have least phase separation and better flowability during spray drying. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Optimization of the Enzymatic Saccharification Process of Milled Orange Wastes

    Directory of Open Access Journals (Sweden)

    Daniel Velasco

    2017-08-01

    Full Text Available Orange juice production generates a very high quantity of residues (Orange Peel Waste or OPW-50–60% of total weight that can be used for cattle feed as well as feedstock for the extraction or production of essential oils, pectin and nutraceutics and several monosaccharides by saccharification, inversion and enzyme-aided extraction. As in all solid wastes, simple pretreatments can enhance these processes. In this study, hydrothermal pretreatments and knife milling have been analyzed with enzyme saccharification at different dry solid contents as the selection test: simple knife milling seemed more appropriate, as no added pretreatment resulted in better final glucose yields. A Taguchi optimization study on dry solid to liquid content and the composition of the enzymatic cocktail was undertaken. The amounts of enzymatic preparations were set to reduce their impact on the economy of the process; however, as expected, the highest amounts resulted in the best yields to glucose and other monomers. Interestingly, the highest content in solid to liquid (11.5% on dry basis rendered the best yields. Additionally, in search for process economy with high yields, operational conditions were set: medium amounts of hemicellulases, polygalacturonases and β-glucosidases. Finally, a fractal kinetic modelling of results for all products from the saccharification process indicated very high activities resulting in the liberation of glucose, fructose and xylose, and very low activities to arabinose and galactose. High activity on pectin was also observed, but, for all monomers liberated initially at a fast rate, high hindrances appeared during the saccharification process.

  4. Enzymatic and structural characterization of hydrolysis of gibberellin A4 glucosyl ester by a rice β-D-glucosidase.

    Science.gov (United States)

    Hua, Yanling; Sansenya, Sompong; Saetang, Chiraporn; Wakuta, Shinji; Ketudat Cairns, James R

    2013-09-01

    In order to identify a rice gibberellin ester β-D-glucosidase, gibberellin A4 β-D-glucosyl ester (GA4-GE) was synthesized and used to screen rice β-glucosidases. Os3BGlu6 was found to have the highest hydrolysis activity to GA4-GE among five recombinantly expressed rice glycoside hydrolase family GH1 enzymes from different phylogenic clusters. The kinetic parameters of Os3BGlu6 and its mutants E178Q, E178A, E394D, E394Q and M251N for hydrolysis of p-nitrophenyl β-D-glucopyranoside (pNPGlc) and GA4-GE confirmed the roles of the catalytic acid/base and nucleophile for hydrolysis of both substrates and suggested M251 contributes to binding hydrophobic aglycones. The activities of the Os3BGlu6 E178Q and E178A acid/base mutants were rescued by azide, which they transglucosylate to produce β-D-glucopyranosyl azide, in a pH-dependent manner, while acetate also rescued Os3BGlu6 E178A at low pH. High concentrations of sodium azide (200-400 mM) inhibited Os3BGlu6 E178Q but not Os3BGlu6 E178A. The structures of Os3BGlu6 E178Q crystallized with either GA4-GE or pNPGlc had a native α-D-glucosyl moiety covalently linked to the catalytic nucleophile, E394, which showed the hydrogen bonding to the 2-hydroxyl in the covalent intermediate. These data suggest that a GH1 β-glucosidase uses the same retaining catalytic mechanism to hydrolyze 1-O-acyl glucose ester and glucoside. Copyright © 2013 Elsevier Inc. All rights reserved.

  5. Optimization of reaction conditions for enzymatic viscosity reduction and hydrolysis of wheat arabinoxylan in an industrial ethanol fermentation residue

    DEFF Research Database (Denmark)

    Sørensen, H.R.; Pedersen, S.; Meyer, Anne Boye Strunge

    2006-01-01

    with a 50:50 mixture of an enzyme preparation from Humicola insolens, Ultraflo L, and a cellulolytic enzyme preparation from Trichoderma reesei, Celluclast 1.5 L. This enzyme mixture was previously shown to exhibit a synergistic action on arabinoxylan degradation. The viscosity of vinasse decreased...... of enzyme-catalyzed hydrolysis of arabinoxylan, beta-glucan, and cellulose. In designed response surface experiments, the optimal enzyme reaction conditions with respect to pH and temperature of the vinasse, the vinasse supernatant (mainly soluble material), and the vinasse sediment (mainly insoluble...

  6. Solubilization of industrial grade plant protein by enzymatic hydrolysis monitored by vibrational and nuclear magnetic resonance spectroscopy

    DEFF Research Database (Denmark)

    Bevilacqua, Marta; Pratico, Giulia; Plesner, Johanne

    2017-01-01

    Protein hydrolysates are of great interest in the food industry due to their nutritional and functional properties, but their use often implies solubilization in water and therefore hamper the use of plant proteins with inherent low water solubility. Protein solubility in water can be modified...... (1H NMR and IR) coupled with chemometrics analysis in monitoring the hydrolysis of five different industrial grade plant proteins by the enzyme Alcalase. Logarithmic modeling of the PCA (Principal Component Analysis) scores confirmed that they can represent a measurement of the solubilized protein...

  7. NMR spectrometric assay for determining enzymatic hydrolysis of β-lactam antibiotics with bacteria in aqueous solution

    International Nuclear Information System (INIS)

    O'hara, K.; Shiomi, Y.; Kono, M.

    1984-01-01

    An application of a nuclear magnetic resonance (NMR) spectrometer for the measurement of β-lactamase activity in clinical material containing bacteria is presented. By means of proton ( 1 H)-NMR, it was easy to measure quantitatively β-lactamase activity in human bacteriuria, without performing any such pretreatment as isolation of bacteria or extraction of crude enzymes and without preparing special reagents for the detection. This is the first report on the application of 1 H-NMR analysis of structural changes for determining hydrolysis of β-lactam antibiotics with β-lactamase-producing bacteria in aqueous solution. (Auth.)

  8. Chemical catalysis in biodiesel production (I): enzymatic catalysis processes

    International Nuclear Information System (INIS)

    Jachmarian, I.; Dobroyan, M.; Veira, J.; Vieitez, I.; Mottini, M.; Segura, N.; Grompone, M.

    2009-01-01

    There are some well known advantages related with the substitution of chemical catalysis by enzymatic catalysis processes.Some commercial immobilized lipases are useful for the catalysis of bio diesel reaction, which permits the achievement of high conversions and the recovery of high purity products, like a high quality glycerine. The main disadvantage of this alternative method is related with the last inactivation of the enzyme (by both the effect of the alcohol and the absorption of glycerol on catalyst surface), which added to the high cost of the catalyst, produces an unfavourable economical balance of the entire process. In the work the efficiency of two commercial immobilized lipases (Lipozyme TL IM y Novozyme 435 NNovozymes-Dinamarca) in the catalysis of the continuous transesterification of sunflower oil with different alcohols was studied. The intersolubility of the different mixturesinvolving reactans (S oil/alkyl esters/alcohol) and products (P mixtures with a higher content of 1% of glycerol,while for ethanol homogeneous mixtures were obtained at 12% of glycerol (44.44 12).Using and ethanolic substrate at the proportion S=19:75:6 and Lipozyme TL IM, it was possible to achieve a 98% of convertion to the corresponding biodiesel.When Novozymes 435 catalyzed the process it was possible to increase the oil concentration in the substrateaccording to proportion S=35:30:35, and a 78% conversion was obtained. The productivity shown by the firt enzyme was 70mg biodiesel g enzime-1, hora-1 while with the second one the productivity increased to 230. Results suggested that the convenient adjustement of substrate composition with the addition of biodiesel to reactants offers an efficient method for maximizing the enzyme productivity, hence improving the profitability of the enzymatic catalyzed process. (author)

  9. Improving the industrial production of 6-APA: enzymatic hydrolysis of penicillin G in the presence of organic solvents.

    Science.gov (United States)

    Abian, Olga; Mateo, César; Fernández-Lorente, Gloria; Guisán, José M; Fernández-Lafuente, Roberto

    2003-01-01

    The hydrolysis of penicillin G in the presence of an organic solvent, used with the purpose of extracting it from the culture medium, may greatly simplify the industrial preparation of 6-APA. However, under these conditions, PGA immobilized onto Eupergit displays very low stability (half-life of 5 h in butanone-saturated water) and a significant degree of inhibition by the organic solvent (30%). The negative effect of the organic solvent strongly depended on the type of solvent utilized: water saturated with butanone (around 28% v/v) had a much more pronounced negative effect than that of methylisobutyl ketone (MIBK) (solubility in water was only 2%). These problems were sorted out by using a new penicillin G acylase derivative designed to work in the presence of organic solvents (with each enzyme molecule surrounded by an hydrophilic artificial environment) and a suitable organic solvent (MIBK). Using such solvent, this derivative kept its activity unaltered for 1 week at 32 degrees C. Moreover, the enzyme activity was hardly inhibited by the presence of the organic solvent. In this way, the new enzyme derivative thus prepared enables simplification of the industrial hydrolysis of penicillin G.

  10. Chemical and morphological characterization of sugarcane bagasse submitted to a delignification process for enhanced enzymatic digestibility

    Directory of Open Access Journals (Sweden)

    Rezende Camila

    2011-11-01

    Full Text Available Abstract Background In recent years, biorefining of lignocellulosic biomass to produce multi-products such as ethanol and other biomaterials has become a dynamic research area. Pretreatment technologies that fractionate sugarcane bagasse are essential for the successful use of this feedstock in ethanol production. In this paper, we investigate modifications in the morphology and chemical composition of sugarcane bagasse submitted to a two-step treatment, using diluted acid followed by a delignification process with increasing sodium hydroxide concentrations. Detailed chemical and morphological characterization of the samples after each pretreatment condition, studied by high performance liquid chromatography, solid-state nuclear magnetic resonance, diffuse reflectance Fourier transformed infrared spectroscopy and scanning electron microscopy, is reported, together with sample crystallinity and enzymatic digestibility. Results Chemical composition analysis performed on samples obtained after different pretreatment conditions showed that up to 96% and 85% of hemicellulose and lignin fractions, respectively, were removed by this two-step method when sodium hydroxide concentrations of 1% (m/v or higher were used. The efficient lignin removal resulted in an enhanced hydrolysis yield reaching values around 100%. Considering the cellulose loss due to the pretreatment (maximum of 30%, depending on the process, the total cellulose conversion increases significantly from 22.0% (value for the untreated bagasse to 72.4%. The delignification process, with consequent increase in the cellulose to lignin ratio, is also clearly observed by nuclear magnetic resonance and diffuse reflectance Fourier transformed infrared spectroscopy experiments. We also demonstrated that the morphological changes contributing to this remarkable improvement occur as a consequence of lignin removal from the sample. Bagasse unstructuring is favored by the loss of cohesion between

  11. Co-extraction of soluble and insoluble sugars from energy sorghum based on a hydrothermal hydrolysis process.

    Science.gov (United States)

    Yu, Qiang; Tan, Xuesong; Zhuang, Xinshu; Wang, Qiong; Wang, Wen; Qi, Wei; Zhou, Guixiong; Luo, Yu; Yuan, Zhenhong

    2016-12-01

    A process for co-extraction of soluble and insoluble sugars from energy sorghum (ES) was developed based on hydrothermal hydrolysis (HH). Two series of ES were investigated: one (N) with a high biomass yield displayed a higher recalcitrance to sugar release, whereas the second (T) series was characterized by high sugar extraction. The highest total xylose recoveries of 87.2% and 98.7% were obtained for N-11 and T-106 under hydrolysis conditions of 180°C for 50min and 180°C for 30min, respectively. Moreover, the T series displayed higher enzymatic digestibility (ED) than the N series. The high degree of branching (arabinose/xylose ratio) and acetyl groups in the hemicellulose chains of T-106 would be expected to accelerate sugar release during the HH process. In addition, negative correlations between ED and the lignin content, crystallinity index (CrI) and syringyl/guaiacyl (S/G) lignin ratio were observed. Furthermore, finding ways to overcome the thickness of the cell wall and heterogeneity of its chemical composition distribution would make cellulose more accessible to the enzyme. Copyright © 2016 Elsevier Ltd. All rights reserved.

  12. Algorithms Development in Detection of the Gelatinization Process during Enzymatic ‘Dodol’ Processing

    Directory of Open Access Journals (Sweden)

    Azman Hamzah

    2013-09-01

    Full Text Available Computer vision systems have found wide application in foods processing industry to perform quality evaluation. The systems enable to replace human inspectors for the evaluation of a variety of quality attributes. This paper describes the implementation of the Fast Fourier Transform and Kalman filtering algorithms to detect the glutinous rice flour slurry (GRFS gelatinization in an enzymatic „dodol. processing. The onset of the GRFS gelatinization is critical in determining the quality of an enzymatic „dodol.. Combinations of these two algorithms were able to detect the gelatinization of the GRFS. The result shows that the gelatinization of the GRFS was at the time range of 11.75 minutes to 14.75 minutes for 24 batches of processing. This paper will highlight the capability of computer vision using our proposed algorithms in monitoring and controlling of an enzymatic „dodol. processing via image processing technology.

  13. Algorithms Development in Detection of the Gelatinization Process during Enzymatic ‘Dodol’ Processing

    Directory of Open Access Journals (Sweden)

    Azman Hamzah

    2007-11-01

    Full Text Available Computer vision systems have found wide application in foods processing industry to perform the quality evaluation. The systems enable to replace human inspectors for the evaluation of a variety of quality attributes. This paper describes the implementation of the Fast Fourier Transform and Kalman filtering algorithms to detect the glutinous rice flour slurry (GRFS gelatinization in an enzymatic ‘dodol’ processing. The onset of the GRFS gelatinization is critical in determining the quality of an enzymatic ‘dodol’. Combinations of these two algorithms were able to detect the gelatinization of the GRFS. The result shows that the gelatinization of the GRFS was at the time range of 11.75 minutes to 15.33 minutes for 20 batches of processing. This paper will highlight the capability of computer vision using our proposed algorithms in monitoring and controlling of an enzymatic ‘dodol’ processing via image processing technology.

  14. Production of alkyl esters from macaw palm oil by a sequential hydrolysis/esterification process using heterogeneous biocatalysts: optimization by response surface methodology.

    Science.gov (United States)

    Bressani, Ana Paula P; Garcia, Karen C A; Hirata, Daniela B; Mendes, Adriano A

    2015-02-01

    The present study deals with the enzymatic synthesis of alkyl esters with emollient properties by a sequential hydrolysis/esterification process (hydroesterification) using unrefined macaw palm oil from pulp seeds (MPPO) as feedstock. Crude enzymatic extract from dormant castor bean seeds was used as biocatalyst in the production of free fatty acids (FFA) by hydrolysis of MPPO. Esterification of purified FFA with several alcohols in heptane medium was catalyzed by immobilized Thermomyces lanuginosus lipase (TLL) on poly-hydroxybutyrate (PHB) particles. Under optimal experimental conditions (mass ratio oil:buffer of 35% m/m, reaction temperature of 35 °C, biocatalyst concentration of 6% m/m, and stirring speed of 1,000 rpm), complete hydrolysis of MPPO was reached after 110 min of reaction. Maximum ester conversion percentage of 92.4 ± 0.4% was reached using hexanol as acyl acceptor at 750 mM of each reactant after 15 min of reaction. The biocatalyst retained full activity after eight successive cycles of esterification reaction. These results show that the proposed process is a promising strategy for the synthesis of alkyl esters of industrial interest from macaw palm oil, an attractive option for the Brazilian oleochemical industry.

  15. Enzymatic process development for the extraction of ferulic from wheat bran [abstract

    Directory of Open Access Journals (Sweden)

    Blecker, C.

    2010-01-01

    Full Text Available The agro-industries generate thousands of tons of by-products, such as cereal bran or sugar beet pulps, each year. For instance, in the Walloon Region, wheat transformation industry produces about 200,000 t of bran annually. Most of those by-products are, at best, used for cattle feeding. Through biocracking, this biomass may however constitute a renewable source for various value-added molecules of interest. These include dietary fiber, proteins, antioxidants, etc. The Feruzyme project focuses on ferulic acid, a major example of the hydroxycinnamic acids. These phenolic compounds show excellent antioxidant ability, and are found in relative abundance in cereal bran (about 6.6 mg.g-1, dry basis, in wheat bran. Ferulic acid (along with other hydroxycinnamic acids is in majority (usually about 80% ester-linked to other constitutive elements of the cell wall, namely arabinoxylans. Its enzymatic release depends mainly on the breaking of its ester linkage by Ferulic Acid Esterases (FAE, EC 3.1.1.73, which works in synergy with arabinoxylan-degrading enzymes (hemicellulase, including xylanase. Cellulase and even protease may also help by "unweaving" further the complex, cross-linked structure of bran cell-wall. The aim of our project is to design a process, starting from raw wheat bran to obtain purified ferulic acid, either crystallized or in concentrated solution. Furthermore, this process should be feasible at pilot scale, as it is meant to commercial application. Bran pre-treatment may impact the efficiency of the enzymatic action, by facilitating the access of the enzymes to their substrate (grinding, micronisation, or by modifying cell-wall structure (extrusion, steam-explosion, etc. processes involving non-enzymatic hydrolysis. The composition of the bran may also be altered, for instance by destarching, but also by pearling, this process being able to separate richer layers within the bran. Simpler process, like fine sieving of ground bran, is

  16. HIDROLISIS IKAN BERNILAI EKONOMI RENDAH SECARA ENZIMATIS MENGGUNAKAN PROTEASE BIDURI [Enzymatic Hydrolysis of Low Economic Value Fishes using Biduri’s Protease

    Directory of Open Access Journals (Sweden)

    Yuli Witono1*

    2015-07-01

    Full Text Available Fish protein hydrolyzate is a product obtained from the decomposition of fish proteins into short-chain compounds due to the hydrolysis process either by enzymes, acids, or bases. The purpose of this study was to optimize the production of fish protein hydrolyzate from the low economic value fishes including 'bibisan' (Apogon albimaculosus, 'baji-baji' (Platycephalidae cymbacephalus, and the 'lidah' (Cynoglossus lingua obtained from Talango Island, Madura. Production of fish protein hydrolyzate was conducted using (Calotropis gigantea protease at various concentrations (0, 0.7, 1.4, and 2.1 Unit/g and at various hydrolysis times (0, 1.5, and 3 h. The experimental design was a Completely Randomized Design with two factors and the experiments were carried out in triplicates. The results showed that interactions between protease concentrations and hydrolysis times significantly affected (at 5% level test the soluble proteins, maillard products, and the level of rancidity measured as thiobarbituric acid (TBA. The best fish hydrolyzate product based on the soluble protein parameter was resulted from 2.1 unit/g of biduri’s protease with a hydrolysis time of 1.5 h. The hydrolyzate produced had 3.51% of soluble proteins, a maillard value of 0.63, and rancidity levels of 12.21 mmol TBA/kg.

  17. Efficient Hydrolysis of Rice Straw into Xylose and Glucose by a Two-step Process

    Directory of Open Access Journals (Sweden)

    YAN Lu-lu

    2016-07-01

    Full Text Available The hydrolysis of rice straw into xylose and glucose in dilute sulfuric acid aqueous solution was studied with a two-step process in batch autoclave reactor. The results showed that compared with the traditional one-step acid hydrolysis, both xylose and glucose could be produced in high yields from rice straw by using the two-step acid hydrolysis process. The effects of reaction temperature, reaction time, the amount of rice straw and acid concentration on the hydrolysis of rice straw were systematically studied, and showed that except initial rice straw loading amount, the other parameters had remarkable influence on the products distribution and yields. In the first-step of the hydrolysis process, a high xylose yield of 162.6 g·kg-1 was obtained at 140℃ after 120 min reaction time. When the solid residues from the first step were subjected to a second-step hydrolysis, a glucose yield as high as 216.5 g·kg-1 could be achieved at 180℃ after 120 min. This work provides a promising strategy for the efficient and value-added utilization of agricultural wastes such as rice straw.

  18. Enzymatic hydrolysis of short-chain lecithin/long-chain phospholipid unilamellar vesicles: sensitivity of phospholipases to matrix phase state.

    Science.gov (United States)

    Gabriel, N E; Agman, N V; Roberts, M F

    1987-11-17

    Short-chain lecithin/long-chain phospholipid unilamellar vesicles (SLUVs), unlike pure long-chain lecithin vesicles, are excellent substrates for water-soluble phospholipases. Hemolysis assays show that greater than 99.5% of the short-chain lecithin is partitioned in the bilayer. In these binary component vesicles, the short-chain species is the preferred substrate, while the long-chain phospholipid can be treated as an inhibitor (phospholipase C) or poor substrate (phospholipase A2). For phospholipase C Bacillus cereus, apparent Km and Vmax values show that bilayer-solubilized diheptanoylphosphatidylcholine (diheptanoyl-PC) is nearly as good a substrate as pure micellar diheptanoyl-PC, although the extent of short-chain lecithin hydrolysis depends on the phase state of the long-chain lipid. For phospholipase A2 Naja naja naja, both Km and Vmax values show a greater range: in a gel-state matrix, diheptanoyl-PC is hydrolyzed with micellelike kinetic parameters; in a liquid-crystalline matrix, the short-chain lecithin becomes comparable to the long-chain component. Both enzymes also show an anomalous increase in specific activity toward diheptanoyl-PC around the phase transition temperature of the long-chain phospholipid. Since the short-chain lecithin does not exhibit a phase transition, this must reflect fluctuations in head-group area or vertical motions of the short-chain lecithin caused by surrounding long-chain lecithin molecules. These results are discussed in terms of a specific model for SLUV hydrolysis and a general explanation for the "interfacial activation" observed with water-soluble phospholipases.

  19. Reactor design for minimizing product inhibition during enzymatic lignocellulose hydrolysis II. Quantification of inhibition and suitability of membrane reactors

    DEFF Research Database (Denmark)

    Andric, Pavle; Meyer, Anne S.; Jensen, Peter Arendt

    2010-01-01

    conversion are required for alleviation of glucose product inhibition. Supported by numerous calculations this review assesses the quantitative aspects of glucose product inhibition on enzyme-catalyzed cellulose degradation rates. The significance of glucose product inhibition on dimensioning of different......Product inhibition of cellulolytic enzymes affects the efficiency of the biocatalytic conversion of lignocellulosic biomass to ethanol and other valuable products. New strategies that focus on reactor designs encompassing product removal, notably glucose removal, during enzymatic cellulose...... reactor features, including system set-up, dilution rate, glucose output profile, and the problem of cellobiose are examined to illustrate the quantitative significance of the glucose product inhibition and the total glucose concentration on the cellulolytic conversion rate. Comprehensive overviews...

  20. Processing of micro-nano bacterial cellulose with hydrolysis method as a reinforcing bioplastic

    Science.gov (United States)

    Maryam, Maryam; Dedy, Rahmad; Yunizurwan, Yunizurwan

    2017-01-01

    Nanotechnology is the ability to create and manipulate atoms and molecules on the smallest of scales. Their size allows them to exhibit novel and significantly improved physical, chemical, biological properties, phenomena, and processes because of their size. The purpose of this research is obtaining micro-nano bacterial cellulose as reinforcing bioplastics. Bacterial cellulose (BC) was made from coconut water for two weeks. BC was dried and grinded. Bacterial cellulose was given purification process with NaOH 5% for 6 hours. Making the micro-nano bacterial cellulose with hydrolysis method. Hydrolysis process with hydrochloric acid (HCl) at the conditions 3,5M, 55°C, 6 hours. Drying process used spray dryer. The hydrolysis process was obtained bacterial cellulose with ±7 μm. The addition 2% micro-nano bacterial cellulose as reinforcing in bioplastics composite can improve the physical characteristics.

  1. Processing of micro-nano bacterial cellulose with hydrolysis method as a reinforcing bioplastic

    International Nuclear Information System (INIS)

    Maryam, Maryam; Yunizurwan, Yunizurwan; Dedy, Rahmad

    2017-01-01

    Nanotechnology is the ability to create and manipulate atoms and molecules on the smallest of scales. Their size allows them to exhibit novel and significantly improved physical, chemical, biological properties, phenomena, and processes because of their size. The purpose of this research is obtaining micro-nano bacterial cellulose as reinforcing bioplastics. Bacterial cellulose (BC) was made from coconut water for two weeks. BC was dried and grinded. Bacterial cellulose was given purification process with NaOH 5% for 6 hours. Making the micro-nano bacterial cellulose with hydrolysis method. Hydrolysis process with hydrochloric acid (HCl) at the conditions 3,5M, 55°C, 6 hours. Drying process used spray dryer. The hydrolysis process was obtained bacterial cellulose with ±7 μm. The addition 2% micro-nano bacterial cellulose as reinforcing in bioplastics composite can improve the physical characteristics. (paper)

  2. Hydrolysis of lactose with -D-galactosidase

    Directory of Open Access Journals (Sweden)

    Vesna Stehlik-Tomas

    2001-06-01

    Full Text Available The conditions of lactose hydrolysis with enzyme preparation of D-galactosidase were investigated. The aim of this work was to considered the use of whey in fermentative processes with yeast Saccharomyces cerevisiae. Enzymatic hydrolysis was conducted at different temperatures, with different lactose concentrations in medium and different concentrations of added enzyme. The results show that optimal temperature for hydrolysis was 40°C. The optimal amount of enzyme preparation was 2 gL-1 in lactose medium with 5-10 % lactose.

  3. Improvement of the enzymatic hydrolysis of furfural residues by pretreatment with combined green liquor and hydrogen peroxide.

    Science.gov (United States)

    Yu, Hai-Long; Tang, Yong; Xing, Yang; Zhu, Li-Wei; Jiang, Jian-Xin

    2013-11-01

    A potential commercial pretreatment for furfural residues (FRs) was investigated by using a combination of green liquor and hydrogen peroxide (GL-H2O2). The results showed that 56.2% of lignin removal was achieved when the sample was treated with 0.6 g H2O2/g-DS (dry substrate) and 6 mL GL/g-DS at 80 °C for 3 h. After 96 h hydrolysis with 18 FPU/g-cellulose for cellulase, 27 CBU/g-cellulose for β-glucosidase, the glucose yield increased from 71.2% to 83.6%. Ethylenediaminetetraacetic acid was used to reduce the degradation of H2O2, the glucose yield increased to 90.4% after the addition of 1% (w/w). The untreated FRs could bind more easily to cellulase than pretreated FRs could. The structural changes on the surface of sample were characterized by X-ray photoelectron spectroscopy. The results indicated that the surface lignin could be effectively removed during pretreatment, thereby decreasing the enzyme-lignin binding activity. Moreover, the carbonyl from lignin plays an important role in cellulase binding. Copyright © 2013 Elsevier Ltd. All rights reserved.

  4. Metal alkoxides as starting materials for hydrolysis processes

    International Nuclear Information System (INIS)

    Mukhtar, Omaima Awad

    1999-12-01

    In this thesis the preparation of some metal alkoxides and their hydrolysis products were studied. The characteristic of each prepared alkoxides and their hydrolyzates were determined. Tetra ethoxysilane was prepared by the elemental route (the reaction of silicon powder with liquid ethanol) in the presence of tin ethoxide as a catalyst. The use of tin alkoxide is considered one of the most developed ways used recently in chemistry, compared to the usage of acids and bases as catalyst previously. It had been confirmed by the usage of (infrared) IR spectroscopy, the structure of the prepared material. Also tin isopropoxide had been prepared and hydrolyzed. Ethoxides of aluminium, magnesium and tin had been prepared by the elemental route. The gelation product had been analyzed. tetraethoxysilane had been also prepared by the halosilane route. Isopropoxide of each aluminium, magnesium and tin had been synthesized, hydrolyzed, allowed to gel and analyzed by IR (infrared) spectroscopy and gas-liquid chromatography. However, results obtained indicated that tin ethoxide is an effective catalyst in the direct synthesis of tetraethoxysilane from silicon powder and liquid ethanol. Gas-liquid chromatography, infra-red (IR) analysis showed that the final reaction product was tetraethoxysilane. (Author)

  5. Enzymatic hydrolysis of various pretreated lignocellulosic substrates and the fermentation of the liberated sugars to ethanol and butanediol

    Energy Technology Data Exchange (ETDEWEB)

    Saddler, J.N.; Mes-Hartree, M.; Yu, E.K.C.; Brownell, H.H.

    1983-01-01

    Aspen wood and wheat straw were pretreated by exposure to steam at elevated temperatures. Chemical analysis of the substrates revealed that steam explosion differentially decomposed the pentosan component while leaving the glucan portion relatively unchanged. The pretreated residues could be used as substrates for growth of Trichoderma reesei C30 and T. harzianum E58. The cellulase activities detected were in some cases three times as high as those found when Solka Floc was used as the substrate. Culture filtrates of T. harzianum E58 could efficiently hydrolyze the hemicellulose-rich water-soluble fractions. This material was fermented by Klebsiella pneumoniae with 0.4-0.5 g of 2,3-butanediol produced per gram of sugar utilized. Once the steam-exploded residues had been water and alkali extracted, the enzymatically hydrolyzed substrates were readily fermented by Saccharomyces cerevisiae or Zymononas mobilis with values as high as 2% (w/v) ethanol obtained from 5% steam-exploded wood fractions. 30 references, 2 figures, 8 tables.

  6. Pretreating lignocellulosic biomass by the concentrated phosphoric acid plus hydrogen peroxide (PHP) for enzymatic hydrolysis: evaluating the pretreatment flexibility on feedstocks and particle sizes.

    Science.gov (United States)

    Wang, Qing; Wang, Zhanghong; Shen, Fei; Hu, Jinguang; Sun, Fubao; Lin, Lili; Yang, Gang; Zhang, Yanzong; Deng, Shihuai

    2014-08-01

    In order to seek a high-efficient pretreatment path for converting lignocellulosic feedstocks to fermentable sugars by enzymatic hydrolysis, the concentrated H₃PO₄ plus H₂O₂ (PHP) was attempted to pretreat different lignocellulosic biomass for evaluating the pretreatment flexibility on feedstocks. Meanwhile, the responses of pretreatment to particle sizes were also evaluated. When the PHP-pretreatment was employed (final H₂O₂ and H₃PO₄ concentration of 1.77% and 80.0%), 71-96% lignin and more than 95% hemicellulose in various feedstocks (agricultural residues, hardwood, softwood, bamboo, and their mixture, and garden wastes mixture) can be removed. Consequently, more than 90% glucose conversion was uniformly achieved indicating PHP greatly improved the pretreatment flexibility to different feedstocks. Moreover, when wheat straw and oak chips were PHP-pretreated with different sizes, the average glucose conversion reached 94.9% and 100% with lower coefficient of variation (7.9% and 0.0%), which implied PHP-pretreatment can significantly weaken the negative effects of feedstock sizes on subsequent conversion. Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Microplate-Based Evaluation of the Sugar Yield from Giant Reed, Giant Miscanthus and Switchgrass after Mild Chemical Pre-Treatments and Hydrolysis with Tailored Trichoderma Enzymatic Blends.

    Science.gov (United States)

    Cianchetta, Stefano; Bregoli, Luca; Galletti, Stefania

    2017-11-01

    Giant reed, miscanthus, and switchgrass are considered prominent lignocellulosic feedstocks to obtain fermentable sugars for biofuel production. The bioconversion into sugars requires a delignifying pre-treatment step followed by hydrolysis with cellulase and other accessory enzymes like xylanase, especially in the case of alkali pre-treatments, which retain the hemicellulose fraction. Blends richer in accessory enzymes than commercial mix can be obtained growing fungi on feedstock-based substrates, thus ten selected Trichoderma isolates, including the hypercellulolytic strain Trichoderma reesei Rut-C30, were grown on giant reed, miscanthus, or switchgrass-based substrates. The produced enzymes were used to saccharify the corresponding feedstocks, compared to a commercial enzymatic mix (6 FPU/g). Feedstocks were acid (H 2 SO 4 0.2-2%, w/v) or alkali (NaOH 0.02-0.2%, w/v) pre-treated. A microplate-based approach was chosen for most of the experimental steps due to the large number of samples. The highest bioconversion was generally obtained with Trichoderma harzianum Or4/99 enzymes (78, 89, and 94% final sugar yields at 48 h for giant reed, miscanthus, and switchgrass, respectively), with significant increases compared to the commercial mix, especially with alkaline pre-treatments. The differences in bioconversion yields were only partially caused by xylanases (maximum R 2  = 0.5), indicating a role for other accessory enzymes.

  8. Enzymatic hydrolysis of multi-use forage energy crops, year 2 report: Studies on the improvement of reaction conditions, differences between forages. SRC technical report No. 141, and SRC publication No. C-711-6-B-83

    Energy Technology Data Exchange (ETDEWEB)

    Jackson, L.J.; Coxworth, E.C.

    1983-12-31

    The main objective of the work described in this report is to optimize the conversion of forages and crop residues to simple sugars, and to determine the quantity of protein that can be readily recovered after enzymatic hydrolysis of those materials. The simple sugars would be used as substrates for fermentation to fuels and chemicals, and the protein is a potentially valuable byproduct for use as fertilizer or feed. The plant materials studied were kochia, Jerusalem artichoke, pea stem and chaff, oilseed radish, alfalfa, and slender wheat grass. The enzymes used in the hydrolysis were Onozuka R-10, Celluclast 200L Type N, and cellobiase 250L. Results reported include comparisons of enzymatic reactivity of the materials studied, the quantity of protein remaining after treatment, and the dry matter solubility of the materials achieved using the different enzymes.

  9. Effect of the steam explosion pretreatment on enzymatic hydrolysis of eucalyptus wood and sweet sorghum baggages; Efecto del pretratamiento con explosion por vapor en la hidrolisis enzimatica de madera de eucalipto y bagazo de sorgo

    Energy Technology Data Exchange (ETDEWEB)

    Negro, M J; Martinez, J M; Manero, J; Saez, F; Martin, C

    1991-07-01

    The effect of steam explosion treatment on the enzymatic hydrolysis yield of two different lignocellulosic substrates is studied. Raw materials have been pretreated in a pilot plant designed to work in batch and equipped with a reactor vessel of 2 1 working volume where biomass was heated at the desired temperature and then exploded and recovered in a cyclone. Temperatures from 190 to 230 degree celsius and reaction times from 2 to 8 min. have been assayed. The efficiency of the steam explosion treatment has been evaluated on the composition of the lignocellulosic materials as well as on their enzymatic hydrolysis yield using a cellulolytic complex from T. reesel. Results show a high solubilization rate of hemicelluloses and variable losses of cellulose and lignin depending on the conditions tested. Enzymatic hydrolysis yields of both substrates experimented remarkable increments, corresponding the highest values obtained to 210 degree celsius; 2 min. and 21O degree celsius; 4 min. for sorghum bagasse and eucalyptus wood respectively. (Author) 13 refs.

  10. Analysis of the hydrolysis process in the formation of supergene zone mining areas

    Directory of Open Access Journals (Sweden)

    Sherstjuk N.P.

    2010-06-01

    Full Text Available The analysis of processes of hydrolysis of silicates and alumosilicat which arrive in a landscape from tails of enrichment of iron ore is carried out. Assessment and forecast formation of minerals zone hipcrhenezu iron deposits was carried out.

  11. Rationale for using integrated enzymatic preparation for receiving food fibers from secondary resources of vegetable material processing

    Directory of Open Access Journals (Sweden)

    Alimov A. V.

    2016-09-01

    presence of enzyme medicine is рН equal to 6.0. The received results allow set the rational modes of enzyme medicine effect (temperature and рН necessary for carrying out enzymatic hydrolysis of secondary resources of aubergines, vegetable marrows and onion processing.

  12. Occurrence of bound 3-monochloropropan-1,2-diol content in commonly consumed foods in Hong Kong analysed by enzymatic hydrolysis and GC-MS detection.

    Science.gov (United States)

    Chung, Stephen W C; Chan, Benny T P; Chung, H Y; Xiao, Ying; Ho, Y Y

    2013-01-01

    The aim of this study was to determine the level of bound 3-monochloropropan-1,2-diol in foodstuffs commonly consumed in Hong Kong, China, by an enzymatic hydrolysis indirect method which proved to be free from interferences. A total of 290 samples were picked up randomly from the local market and analysed. About 73% of these samples were found to contain detectable amounts of bound 3-MCPD. Amongst the 73 food items, bound 3-MCPD was not detected in 13 food items, including extra virgin olive oil, beef ball/salami, beef flank, ham/Chinese ham, nuts, seeds, soy sauce, oyster sauce, butter, yoghurt, cream, cheese and milk. For those found to contain detectable bound 3-MCPD, the content ranged up to 2500 µg kg(-1). The highest mean bound 3-MCPD content among the 14 food groups was in biscuits (440 [50-860] µg kg(-1)), followed by fats and oils (390 [n.d.-2500] µg kg(-1)), snacks (270 [9-1000] µg kg(-1)), and Chinese pastry (270 [n.d.-1200] µg kg(-1)). Among the samples, the highest bound 3-MCPD content was in a grape seed oil (2500 µg kg(-1)), followed by a walnut flaky pastry (1200 µg kg(-1)) and a grilled corn (1000 µg kg(-1)). Basically, the results of this study agreed well with other published results in peer-reviewed journals, except for cheese, cream, ham, nuts and seeds.

  13. Systematic optimization of fed-batch simultaneous saccharification and fermentation at high-solid loading based on enzymatic hydrolysis and dynamic metabolic modeling of Saccharomyces cerevisiae.

    Science.gov (United States)

    Unrean, Pornkamol; Khajeeram, Sutamat; Laoteng, Kobkul

    2016-03-01

    An integrative simultaneous saccharification and fermentation (SSF) modeling is a useful guiding tool for rapid process optimization to meet the techno-economic requirement of industrial-scale lignocellulosic ethanol production. In this work, we have developed the SSF model composing of a metabolic network of a Saccharomyces cerevisiae cell associated with fermentation kinetics and enzyme hydrolysis model to quantitatively capture dynamic responses of yeast cell growth and fermentation during SSF. By using model-based design of feeding profiles for substrate and yeast cell in the fed-batch SSF process, an efficient ethanol production with high titer of up to 65 g/L and high yield of 85 % of theoretical yield was accomplished. The ethanol titer and productivity was increased by 47 and 41 %, correspondingly, in optimized fed-batch SSF as compared to batch process. The developed integrative SSF model is, therefore, considered as a promising approach for systematic design of economical and sustainable SSF bioprocessing of lignocellulose.

  14. Exploration of process parameters for continuous hydrolysis of canola oil, camelina oil and algal oil

    KAUST Repository

    Wang, Weicheng

    2012-07-01

    Thermal hydrolysis of triglycerides to form free fatty acid (FFA) is a well-established industry practice. Recently, this process has been employed as a first step in the production of biofuels from lipids. To that end, batch and continuous hydrolysis of various feedstocks has been examined at the laboratory scale. Canola, the primary feedstock in this paper, camelina and algal oils were converted to high quality FFA. For the different reaction temperatures, the continuous hydrolysis system was found to provide better yields than the laboratory batch system. In addition, CFD simulation with ANSYS-CFX was used to model the performance and reactant/product separation in the continuous, counter-flow reactor. The effects of reaction temperature, water-to-oil ratio (ratio of water and oil volumetric inflow rate), and preheating of the reactants were examined experimentally. Optimization of these parameters has resulted in an improved, continuous process with high mass yields (89-93%, for reactor temperature of 260°C and water-to-oil ratio of 4:1) and energy efficiency (76%, for reactor temperature of 250°C and water-to-oil ratio of 2:1). Based on the product quality and energy efficiency considerations, the reactor temperature of 260°C and water-to-oil ratio of 4:1 have provided the optimal condition for the lab scale continuous hydrolysis reaction. © 2012 Elsevier B.V.

  15. Exploration of process parameters for continuous hydrolysis of canola oil, camelina oil and algal oil

    KAUST Repository

    Wang, Weicheng; Turner, Timothy L.; Stikeleather, Larry F.; Roberts, William L.

    2012-01-01

    Thermal hydrolysis of triglycerides to form free fatty acid (FFA) is a well-established industry practice. Recently, this process has been employed as a first step in the production of biofuels from lipids. To that end, batch and continuous hydrolysis of various feedstocks has been examined at the laboratory scale. Canola, the primary feedstock in this paper, camelina and algal oils were converted to high quality FFA. For the different reaction temperatures, the continuous hydrolysis system was found to provide better yields than the laboratory batch system. In addition, CFD simulation with ANSYS-CFX was used to model the performance and reactant/product separation in the continuous, counter-flow reactor. The effects of reaction temperature, water-to-oil ratio (ratio of water and oil volumetric inflow rate), and preheating of the reactants were examined experimentally. Optimization of these parameters has resulted in an improved, continuous process with high mass yields (89-93%, for reactor temperature of 260°C and water-to-oil ratio of 4:1) and energy efficiency (76%, for reactor temperature of 250°C and water-to-oil ratio of 2:1). Based on the product quality and energy efficiency considerations, the reactor temperature of 260°C and water-to-oil ratio of 4:1 have provided the optimal condition for the lab scale continuous hydrolysis reaction. © 2012 Elsevier B.V.

  16. Optimization of olive oil hydrolysis process using immobilized Lipase from Burkholderia cepacia sp. in Polyurethane

    Directory of Open Access Journals (Sweden)

    Nádia Ligianara Dewes Nyari

    2017-09-01

    Full Text Available The aim of this study was to achieve the best conditions for the  olive oil hydrolysis process at optimal pH and temperature using Burkholderia cepacia lipase immobilized in situ in rigid polyurethane support. The influences of the temperature (13.85 to 56.5ºC and pH (4.18 to 9.82 were evaluated by a central composite rotational experimental design 22. The operational stability and storage conditions were also studied. The olive oil hydrolysis process was optimized in pH 7.0, at 40°C and 15 min of reaction, with 66 and 93 U g-1 of hydrolysis activity in free and immobilized lipase, respectively, with > 700% yield. The immobilized remained stable for up to 40 days of storage at temperatures of 60oC, and for 100 days from 4 to 25°C. The operational stability of the immobilized was 6 continuous cycles. In this way, immobilization showed to be a promising alternative for its application in olive oil hydrolysis, having storage stability and reuse capability.

  17. Overall process considerations for using dilute acid cellulose hydrolysis technology to produce ethanol from biomass

    International Nuclear Information System (INIS)

    Elander, R.; Ibsen, K.; Hayward, T.; Nagle, N.; Torget, R.

    1997-01-01

    Recent advances in reactors, designed for the dilute acid thermochemical treatment of biomass, have resulted in the development of process alternatives in which both cellulose and hemicellulose are hydrolyzed to soluble sugars in high yields. The optimal extent of cellulose hydrolysis will depend on both the performance and economics of the thermochemical treatment operation, and on subsequent unit operations in the bioethanol production process. Examples of subsequent unit operation interactions include the extent to which cellulase enzymes are used to hydrolyze any remaining cellulose, kinetics and conditions of a largely soluble mixed sugar cofermentation, and the extent to which removal of compounds that inhabit fermenting microorganisms is required. In addition, a number of process operation and economic considerations affect the ultimate economic viability of this type of biomass hydrolysis process. These considerations include reactor design issues to accommodate the kinetic parameters of the various hydrolysis and sugar degradation reactions, liquid volume requirements to achieve acceptable sugar yields, sugar concentrations that result from such a process and their impact on subsequent fermentation volumes and ethanol recovery operations, potential co-product opportunities that result from solubilized lignin, and process steam requirements. Several potential whole-process configurations are presented and key process and economic issues for each are discussed. (author)

  18. Impact of variety type and particle size distribution on starch enzymatic hydrolysis and functional properties of tef flours.

    Science.gov (United States)

    Abebe, Workineh; Collar, Concha; Ronda, Felicidad

    2015-01-22

    Tef grain is becoming very attractive in the Western countries since it is a gluten-free grain with appreciated nutritional advantages. However there is little information of its functional properties and starch digestibility and how they are affected by variety type and particle size distribution. This work evaluates the effect of the grain variety and the mill used on tef flour physico-chemical and functional properties, mainly derived from starch behavior. In vitro starch digestibility of the flours by Englyst method was assessed. Two types of mills were used to obtain whole flours of different granulation. Rice and wheat flours were analyzed as references. Protein molecular weight distribution and flour structure by SEM were also analyzed to justify some of the differences found among the cereals studied. Tef cultivar and mill type exhibited important effect on granulation, bulking density and starch damage, affecting the processing performance of the flours and determining the hydration and pasting properties. The color was darker although one of the white varieties had a lightness near the reference flours. Different granulation of tef flour induced different in vitro starch digestibility. The disc attrition mill led to higher starch digestibility rate index and rapidly available glucose, probably as consequence of a higher damaged starch content. The results confirm the adequacy of tef flour as ingredient in the formulation of new cereal based foods and the importance of the variety and the mill on its functional properties. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Process Parameters on the Crystallization and Morphology of Hydroxyapatite Powders Prepared by a Hydrolysis Method

    Science.gov (United States)

    Wang, Moo-Chin; Hon, Min-Hsiung; Chen, Hui-Ting; Yen, Feng-Lin; Hung, I.-Ming; Ko, Horng-Huey; Shih, Wei-Jen

    2013-07-01

    The effects of process parameters on the crystallization and morphology of hydroxyapatite (Ca10(PO4)6(OH)2, HA) powders synthesized from dicalcium phosphate dihydrate (CaHPO4·2H2O, DCPD) using a hydrolysis method have been investigated. X-ray diffraction (XRD), Fourier-transform infrared (FT-IR) spectra, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and selected area electron diffraction (SAED) were used to characterize the synthesized powders. When DCPD underwent hydrolysis in 2.5 NaOH solution (Na(aq)) at 303 K to 348 K (30 °C to 75 °C) for 1 hour, the XRD results revealed that HA was obtained for all the as-dried samples. The SEM morphology of the HA powders for DCPD hydrolysis produced at 348 K (75 °C) shows regular alignment and a short rod shape with a size of 200 nm in length and 50 nm in width. With DCPD hydrolysis in 2.5 M NaOH(aq) holding at 348 K (75 °C) for 1 to 24 hours, XRD results demonstrated that all samples were HA and no other phases could be detected. Moreover, the XRD results also show that all the as-dried powders still maintained the HA structure when DCPD underwent hydrolysis in 0.1 to 5 M NaOH(aq) at 348 K (75 °C) for 1 hour. Otherwise, the full transformation from HA to octa-calcium phosphate (OCP, Ca8H2(PO4)6·5H2O) occurred when hydrolysis happened in 10 M NaOH(aq). FT-IR spectra analysis revealed that some carbonated HA (Ca10(PO4)6(CO3), CHA) had formed. The SEM morphology results show that the 60 to 65 nm width of the uniformly long rods with regular alignment formed in the HA powder aggregates when DCPD underwent hydrolysis in 2.5 M NaOH(aq) at 348 K (75 °C) for 1 hour.

  20. Effect of gelatinization and hydrolysis conditions on the selectivity of starch hydrolysis with alpha-amylase from Bacillus licheniformis.

    Science.gov (United States)

    Baks, Tim; Bruins, Marieke E; Matser, Ariette M; Janssen, Anja E M; Boom, Remko M

    2008-01-23

    Enzymatic hydrolysis of starch can be used to obtain various valuable hydrolyzates with different compositions. The effects of starch pretreatment, enzyme addition point, and hydrolysis conditions on the hydrolyzate composition and reaction rate during wheat starch hydrolysis with alpha-amylase from Bacillus licheniformis were compared. Suspensions of native starch or starch gelatinized at different conditions either with or without enzyme were hydrolyzed. During hydrolysis, the oligosaccharide concentration, the dextrose equivalent, and the enzyme activity were determined. We found that the hydrolyzate composition was affected by the type of starch pretreatment and the enzyme addition point but that it was just minimally affected by the pressure applied during hydrolysis, as long as gelatinization was complete. The differences between hydrolysis of thermally gelatinized, high-pressure gelatinized, and native starch were explained by considering the granule structure and the specific surface area of the granules. These results show that the hydrolyzate composition can be influenced by choosing different process sequences and conditions.

  1. Hydrolysis of alkaline pretreated banana peel

    Science.gov (United States)

    Fatmawati, A.; Gunawan, K. Y.; Hadiwijaya, F. A.

    2017-11-01

    Banana peel is one of food wastes that are rich in carbohydrate. This shows its potential as fermentation substrate including bio-ethanol. This paper presented banana peel alkaline pretreatment and enzymatic hydrolysis. The pretreatment was intended to prepare banana peel in order to increase hydrolysis performance. The alkaline pretreatment used 10, 20, and 30% w/v NaOH solution and was done at 60, 70 and 80°C for 1 hour. The hydrolysis reaction was conducted using two commercial cellulose enzymes. The reaction time was varied for 3, 5, and 7 days. The best condition for pretreatment process was one conducted using 30% NaOH solution and at 80°C. This condition resulted in cellulose content of 90.27% and acid insoluble lignin content of 2.88%. Seven-day hydrolysis time had exhibited the highest reducing sugar concentration, which was7.2869 g/L.

  2. Process development studies on the bioconversion of cellulose and production of ethanol. Progress report, September 1, 1978

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C.R.

    1978-09-01

    Progress is reported in studies on the pretreatment of cellulosic materials to facilitate enzymatic hydrolysis, sulfuric acid hydrolysis, investigation of the Purdue processing scheme including an economic analysis, and the fermentability of the enzymatic hydrolyzate. Progress is also reported on enzyme fermentation studies, hydrolysis reactor development, and utilization of hemicellulose sugars. (JSR)

  3. Production of ethanol from winter barley by the EDGE (enhanced dry grind enzymatic process

    Directory of Open Access Journals (Sweden)

    Kurantz M

    2010-04-01

    Full Text Available Abstract Background US legislation requires the use of advanced biofuels to be made from non-food feedstocks. However, commercialization of lignocellulosic ethanol technology is more complex than expected and is therefore running behind schedule. This is creating a demand for non-food, but more easily converted, starch-based feedstocks other than corn that can fill the gap until the second generation technologies are commercially viable. Winter barley is such a feedstock but its mash has very high viscosity due to its high content of β-glucans. This fact, along with a lower starch content than corn, makes ethanol production at the commercial scale a real challenge. Results A new fermentation process for ethanol production from Thoroughbred, a winter barley variety with a high starch content, was developed. The new process was designated the EDGE (enhanced dry grind enzymatic process. In this process, in addition to the normal starch-converting enzymes, two accessory enzymes were used to solve the β-glucan problem. First, β-glucanases were used to hydrolyze the β-glucans to oligomeric fractions, thus significantly reducing the viscosity to allow good mixing for the distribution of the yeast and nutrients. Next, β-glucosidase was used to complete the β-glucan hydrolysis and to generate glucose, which was subsequently fermented in order to produce additional ethanol. While β-glucanases have been previously used to improve barley ethanol production by lowering viscosity, this is the first full report on the benefits of adding β-glucosidases to increase the ethanol yield. Conclusions In the EDGE process, 30% of total dry solids could be used to produce 15% v/v ethanol. Under optimum conditions an ethanol yield of 402 L/MT (dry basis or 2.17 gallons/53 lb bushel of barley with 15% moisture was achieved. The distillers dried grains with solubles (DDGS co-product had extremely low β-glucan (below 0.2% making it suitable for use in both ruminant

  4. HIDROLISIS ENZIMATIK MINYAK IKAN UNTUK PRODUKSI ASAM LEMAK OMEGA-3 MENGGUNAKAN LIPASE DARI Aspergillus niger [Enzymatic Hydrolysis of Fish Oil for Production of Omega-3 Fatty Acids Using Lipase Derived from Aspergillus niger

    Directory of Open Access Journals (Sweden)

    Sapta Raharja*

    2011-06-01

    Full Text Available Fish oil is the source of important fatty-acid, especially polyunsaturated fatty acid (PUFA omega-3, such as eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. Lipase catalysis activity of Aspergillus niger is low when it is used in fish oil hydrolysis. The activity of the lipase can be increased by adding organic solvent such as hexane into the media. This research aimed to determine temperature, pH and amount of water which produce the highest degree of hydrolysis of fish oil in the presence of hexane. Correlation between the highest degree of hydrolysis and the amount of omega-3 fatty acid was also investigated. The variables used in this research were temperatures (25-65 oC, pH (5-9, and water addition (1-5 %v/v. The highest degree of enzymatic hydrolysis of fish oil in the media without hexane was 28.07 % that was reached at 45oC and pH 5. In the presence of hexane, the highest degree of hydrolysis was 75.12 % which was reached at 5% water addition, temperature 45oC, and pH 5. GC-MS analysis showed that omega-3 fatty acid content especially EPA and DHA increased along with increase in the degree of hydrolysis. Concentration of omega-3 fatty acid produced without hexane addition was 18.42 % with EPA amounted to 12,17% and DHA 0,86%. Meanwhile omega-3 fatty acid content in the presence of hexane reached 21.93 % with EPA amounted to 17.75 % and DHA 1.21 %.

  5. Enzymatic Modification of Sphingomyelin

    DEFF Research Database (Denmark)

    Due to its major role in maintaining the water-retaining properties of the epidermis, ceramide is of great commercial potential in cosmetic and pharmaceuticals such as hair and skin care products. Currently, chemical synthesis of ceramide is a costly process, and developments of alternative cost......-efficient, high yield production methods are of great interest. In the present study, the potential of producing ceramide through the enzymatic hydrolysis of sphingomyelin have been studied. sphingomyelin is a ubiquitous membrane-lipid and rich in dairy products or by-products. It has been verified...... that sphingomyelin modification gives a feasible approach to the potential production of ceramide. The reaction system has been improved through system evaluation and the optimization of several important factors, and phospholipase C from Clostridium perfringens shows higher activity towards the hydrolysis reaction...

  6. Enzymatic processes in alternative reaction media: a mini review

    Directory of Open Access Journals (Sweden)

    Mansour Ghaffari-Moghaddam

    2015-08-01

    Full Text Available Biocatalysis is a growing field in the production of fine chemicals and will most probably increase its share in the future. Enzymatic reactions are carried out under mild conditions, i.e., non-toxic solvents, low temperature and pressure, which eliminates most environmental drawbacks associated with conventional production methods. The superiority of chemo-, regio- and enantioselectivity of enzymes exhibit significant advantages over conventional catalysts for production of fine chemicals, flavors, fragrances, agrochemicals and pharmaceuticals. Enzymes can function both in aqueous and non-aqueous solvents. As a result of the growing scientific and industrial interest towards green chemistry, green solvent systems, which are mainly water, supercritical fluids, ionic liquids, fluorinated solvents, and solvent-free systems have become more popular in biocatalysis. However, the activity and selectivity of an enzyme is heavily dependent on solvent properties. In this review, various green solvents were classified and some of their influential features on enzyme activity were discussed.

  7. Utilization of cellulosic materials through enzymic hydrolysis. 11. Preliminary assessment of an integrated processing scheme

    Energy Technology Data Exchange (ETDEWEB)

    Wilke, C R; Cysewski, G R; Yang, R D

    1976-01-01

    An integrated processing scheme is described for the conversion of a cellulose waste (newsprint) to sugars by enzymic hydrolysis and then to ethanol and yeast by fermentation. The unconverted solids are burned to produce process energy requirements and surplus electric power. With the preliminary design at an estimate total capital investment of $33.4 x 10/sup 6/, 95% ethanol may be produced FOB (free on board) the plant for approx.61 cents/gal, assuming zero cost for cellulosic feed; taking into account interest rates and taxes and a cellulose feed cost of $20/ton the figure becomes $1.67/gal.

  8. Enzymatic hydrolysis of water-soluble wheat arabinoxylan. 1. Synergy between alpha-L-arabinofuranosidases, endo-1,4-beta-xylanases, and beta-xylosidase activities

    DEFF Research Database (Denmark)

    Sørensen, H.R.; Meyer, Anne Boye Strunge; Pedersen, S.

    2003-01-01

    Hydrolysis of arabinoxylan is an important prerequisite for improved utilization of wheat hemicellulose in the ethanol fermentation industry. This study investigates the individual and combined efficiencies of three commercial, cellulytic and hemicellulytic enzyme preparations, Celluclast 1.5 L, ...

  9. Enzyme loading dependence of cellulose hydrolysis of sugarcane bagasse

    Directory of Open Access Journals (Sweden)

    Carlos Martín

    2012-01-01

    Full Text Available The enzymatic hydrolysis of steam-pretreated sugarcane bagasse, either delignified or non-delignified, was studied as a function of enzyme loading. Hydrolysis experiments were carried out using five enzyme loadings (2.5 to 20 FPU/g cellulose and the concentration of solids was 2% for both materials. Alkaline delignification improved cellulose hydrolysis by increasing surface area. For both materials, glucose concentrations increased with enzyme loading. On the other hand, enzyme loadings higher than 15 FPU/g did not result in any increase in the initial rate, since the excess of enzyme adsorbed onto the substrate restricted the diffusion process through the structure.

  10. A green and efficient technology for the degradation of cellulosic materials: structure changes and enhanced enzymatic hydrolysis of natural cellulose pretreated by synergistic interaction of mechanical activation and metal salt.

    Science.gov (United States)

    Zhang, Yanjuan; Li, Qian; Su, Jianmei; Lin, Ye; Huang, Zuqiang; Lu, Yinghua; Sun, Guosong; Yang, Mei; Huang, Aimin; Hu, Huayu; Zhu, Yuanqin

    2015-02-01

    A new technology for the pretreatment of natural cellulose was developed, which combined mechanical activation (MA) and metal salt treatments in a stirring ball mill. Different valent metal nitrates were used to investigate the changes in degree of polymerization (DP) and crystallinity index (CrI) of cellulose after MA+metal salt (MAMS) pretreatment, and Al(NO3)3 showed better pretreatment effect than NaNO3 and Zn(NO3)2. The destruction of morphological structure of cellulose was mainly resulted from intense ball milling, and the comparative studies on the changes of DP and crystal structure of MA and MA+Al(NO3)3 pretreated cellulose samples showed a synergistic interaction of MA and Al(NO3)3 treatments with more effective changes of structural characteristics of MA+Al(NO3)3 pretreated cellulose and substantial increase of reducing sugar yield in enzymatic hydrolysis of cellulose. In addition, the results indicated that the presence of Al(NO3)3 had significant enhancement for the enzymatic hydrolysis of cellulose. Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Comparison of various milling modes combined to the enzymatic hydrolysis of lignocellulosic biomass for bioenergy production: Glucose yield and energy efficiency

    International Nuclear Information System (INIS)

    Licari, A.; Monlau, F.; Solhy, A.; Buche, P.; Barakat, A.

    2016-01-01

    Bagasse is an abundant by-product from sugarcane production that can be used for conversion into biofuels. Nonetheless, the recalcitrant structures of lignocellulosic fibers required a pretreatment prior conversion into biofuels. In this study, four mechanical deconstruction methods were compared in terms of energy demand and energy efficiency at lab scale: BM (ball mill), VBM (vibratory ball mill), CM (centrifugal mill) and JM (jet mill). Results indicate that VBM was more effective compared to BM, JM and CM in enzymatic accessibility and sugars solubilization: VBM-3h > BM-72 h > JM-5000 rpm > CM-0.12 mm. However, preliminary energetic assessment showed that at lab scale, the CM (centrifugal mill) as mechanical fractionation process appears to be the most efficient in terms of energy-efficiency (kg glucose/kWh) compared to BM, VBM and JM. A comparison with literature pretreatments data highlighted that fine and/or ultrafine milling process (BM, VBM, CM) are simpler saccharification technologies, which not required any chemical or water inputs, thus minimizing waste generation and treatment. - Highlights: • VBM (vibro ball milling) was the most effective in decreasing of cellulose crystallinity. • BM (ball milling) was the most effective in increasing surface area. • The highest energy efficiency was obtained with CM (centrifugal milling).

  12. Hydrolysis of maize starch using amylolytic enzymes extracted from ...

    African Journals Online (AJOL)

    Amylases, a-amylase (EC 3.2.1.1, α-1, 4-glucan-4-glucanohydrolase) and glucoamylase (EC 3.2.1.3, α-1, 4; α-1, 6-glucan glucohydrolase; amyloglucosidase), extracted and partially purified from sorghum malt were used to hydrolyze maize starch. The process and products of the enzymatic hydrolysis were also compared ...

  13. Study on the behavior of sulfur in hydrolysis process of titanyl sulfate solution

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Fanbo; Luo, Dongmei, E-mail: dmluo@scu.edu.cn; Zhang, Zhao; Liang, Bin; Yuan, Xizhi; Fu, Li

    2016-06-15

    The existing forms of sulfur in hydrolysis process of titanyl sulfate solution were studied. Also the effects of sulfur on crystal structure, crystallite size and crystal phase transition of the hydrated titanium dioxide(TiO{sub 2}·H{sub 2}O) and titanium dioxide (TiO{sub 2}) were conducted. The analysis and methods of thermogravimetric-differential scanning calorimet (TG-DSC), energy dispersive spectrometer (EDS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), UV–Vis diffuse reflectance spectra and Raman spectroscopy were employed to characterize. The results indicated that the sulfur was present in the form of SO{sub 4}{sup 2−} ions in the hydrolysate of titanyl sulfate solution, and a portion of SO{sub 4}{sup 2−} ions were combined on the surface of hydrated titanium dioxide by chemical adsorption in the forms of inorganic chelating bidentate coordination and covalent sulfate coordination, the residual SO{sub 4}{sup 2−} ions were adsorbed on the surface of hydrated titanium dioxide by physical adsorption. The chemical adsorption of SO{sub 4}{sup 2−} ions were conducive to the formation and stabilization of anatase, which changed the crystal structure, and hindered the transformation of the anatase into rutile. The results of Raman spectroscopy showed that the sulfur was dissociated in the forms of SO{sub 4}{sup 2−} and HSO{sub 4}{sup −} ions during the hydrolysis of titanyl sulfate solution. The characteristic peak at 1004 cm{sup −1} corresponding to a new complex has been observed, which was composed of SO{sub 4}{sup 2−} and hydrated titanium complex ions through the bonding on the surface. In basis of the above experimental results, the hydrolysis process of titanyl sulfate solution was illustrated from the microstructure with 3D atlas. - Highlights: • The SO{sub 4}{sup 2−} ions exist in TiO{sub 2}·H{sub 2}O by chemical and physical adsorption. • The SO{sub 4}{sup 2−} ions are conducive to the formation and

  14. Modeling Evolution of Hydrogen Bonding and Stabilization of Transition States in the Process of Cocaine Hydrolysis Catalyzed by Human Butyrylcholinesterase

    OpenAIRE

    Gao, Daquan; Zhan, Chang-Guo

    2006-01-01

    Molecular dynamics (MD) simulations and quantum mechanical/molecular mechanical (QM/MM) calculations were performed on the prereactive enzyme-substrate complex, transition states, intermediates, and product involved in the process of human butyrylcholinesterase (BChE)-catalyzed hydrolysis of (−)-cocaine. The computational results consistently reveal a unique role of the oxyanion hole (consisting of G116, G117, and A199) in BChE-catalyzed hydrolysis of cocaine, as compared to acetylcholinester...

  15. Application of acid-catalyzed hydrolysis of dispersed organic solvent in developing new microencapsulation process technology.

    Science.gov (United States)

    Lee, Honghwa; Lee, Sunhwa; Bhattacharjee, Himanshu; Sah, Hongkee

    2012-01-01

    The aim of this study was to evaluate a new microencapsulation technology employing an acid-catalyzed solvent extraction method in conjunction to an emulsion-based microencapsulation process. Its process consisted of emulsifying a dispersed phase of poly(D,L-lactide-co-glycolide) and isopropyl formate in an aqueous phase. This step was followed by adding hydrochloric acid to the resulting oil-in-water emulsion, in order to initiate the hydrolysis of isopropyl formate dissolved in the aqueous phase. Its hydrolysis caused the liberation of water-soluble species, that is, isopropanol and formic acid. This event triggered continual solvent leaching out of emulsion droplets, thereby initiating microsphere solidification. This new processing worked well for encapsulation of progesterone and ketoprofen that were chosen as a nonionizable model drug and a weakly acidic one, respectively. Furthermore, the structural integrity of poly(D,L-lactide-co-glycolide) was retained during microencapsulation. The new microencapsulation technology, being conceptually different from previous approaches, might be useful in preparing various polymeric particles.

  16. Enzymatic hydrolsis of pretreated rice straw

    Energy Technology Data Exchange (ETDEWEB)

    Vlasenko, E.Y.; Shoemaker, S.P. [California Inst. of Food and Agricultural Research, Davis, CA (United States); Ding, H. [California Univ., Davis (Canada). Dept. of Food Science and Technology; Labavitch, J.M. [California Univ., Davis, CA (United States). Dept. of Pomology

    1997-02-01

    California rice straw is being evaluated as a feedstock for production of power and fuel. This paper examines the initial steps in the process: pretreatment of rice straw and enzymatic hydrolysis of the polysaccharides in the pretreated material to soluble sugars. Rice straw was subjected to three distinct pretreatment procedures: acid-catalyzed steam explosion (Swan Biomass Company), acid hydrolysis (U.S. DOE National Renewable Energy Laboratory), and ammonia fiber explosion or AFEX (Texas A and M University). Standard conditions for each pretreatment were used, but none was optimized for rice straw specifically. Six commercial cellulases, products of Genencor International (USA), Novo (Denmark), Iogen (Canada) and Fermtech (Russia) were used for hydrolysis. The Swan- and the acid-pretreatments effectively removed hemicellulose from rice straw, providing high yields of fermentable sugars. The AFEX-pretreatment was distinctly different from other pretreatments in that it did not significantly solubilize hemicellulose. All three pretreatment procedures substantially increased enzymatic digestibility of rice straw. Three commercial Trichoderma-reesei-derived enzyme preparations: Cellulase 100L (Iogen), Spezyme CP (Genencor), and Al (Fermtech), were more active on pretreated rice straw compared than others tested. Conditions for hydrolysis of rice straw using Cellulase 100L were evaluated. The supplementation of this enzyme preparation with cellobiase (Novozyme 188) significantly improved the parameters of hydrolysis for the Swan- and the acid-pretreated materials, but did not affect the hydrolysis of the AFEX-pretreated rice straw. (Author)

  17. Optimization of the immobilization process of β-galatosidade by combined entrapment-cross-linking and the kinetics of lactose hydrolysis

    Directory of Open Access Journals (Sweden)

    F. F. Freitas

    2012-03-01

    Full Text Available The immobilization of Aspergillus oryzae β-galactosidase was achieved by entrapment in sodium alginate and gelatin and cross-linking with glutaraldehyde. The optimal concentrations of the aforementioned variables in the immobilization process were determined using an orthogonal central composite design with an orthogonal axial value of 1.35313. The concentrations of alginate, gelatin and glutaraldehyde that provided the greatest enzymatic activity were 6.60%, 4.05% and 3.64% (w/v, respectively. The stability of the immobilized enzyme under the optimal conditions was evaluated through daily activity assays. After 25 uses, a 20% decrease in the enzymatic activity was observed, indicating that the immobilization process could be used to produce a stable biocatalyst. This study investigates the influence of lactose and product concentrations on kinetic reaction hydrolysis. The concentration ranges for the studied variables were 10 to 56 g/L for lactose and 0 to 11.5 g/L for glucose and galactose. Only galactose presented a competitive inhibitory effect.

  18. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Directory of Open Access Journals (Sweden)

    Gupta Rishi

    2012-03-01

    Full Text Available Abstract Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates.

  19. Kinetic study of batch and fed-batch enzymatic saccharification of pretreated substrate and subsequent fermentation to ethanol

    Science.gov (United States)

    2012-01-01

    Background Enzymatic hydrolysis, the rate limiting step in the process development for biofuel, is always hampered by its low sugar concentration. High solid enzymatic saccharification could solve this problem but has several other drawbacks such as low rate of reaction. In the present study we have attempted to enhance the concentration of sugars in enzymatic hydrolysate of delignified Prosopis juliflora, using a fed-batch enzymatic hydrolysis approach. Results The enzymatic hydrolysis was carried out at elevated solid loading up to 20% (w/v) and a comparison kinetics of batch and fed-batch enzymatic hydrolysis was carried out using kinetic regimes. Under batch mode, the actual sugar concentration values at 20% initial substrate consistency were found deviated from the predicted values and the maximum sugar concentration obtained was 80.78 g/L. Fed-batch strategy was implemented to enhance the final sugar concentration to 127 g/L. The batch and fed-batch enzymatic hydrolysates were fermented with Saccharomyces cerevisiae and ethanol production of 34.78 g/L and 52.83 g/L, respectively, were achieved. Furthermore, model simulations showed that higher insoluble solids in the feed resulted in both smaller reactor volume and shorter residence time. Conclusion Fed-batch enzymatic hydrolysis is an efficient procedure for enhancing the sugar concentration in the hydrolysate. Restricting the process to suitable kinetic regimes could result in higher conversion rates. PMID:22433563

  20. Effect of Thermal Processing towards Lipid Oxidation and Non-enzymatic Browning Reactions of Antartic Krill (Euphausia superba) Meal.

    Science.gov (United States)

    Liu, Yanzi; Cong, Peixu; Li, Beijia; Song, Yu; Liu, Yanjun; Xu, Jie; Xue, Changhu

    2018-04-13

    Antarctic krill is a huge source of biomass and prospective high-quality lipid source. Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), nutritionally important lipid components with poor oxidative stability, were used as markers of oxidation during thermal processing of Antarctic krill (Euphausia superba) meal by evaluating the lipolysis, lipid oxidation, and non-enzymatic browning reactions. Liquid chromatography-mass spectrometry of the phospholipids (PLs) and the main oxidation products of free fatty acids (FFAs) and phosphatidylcholine (PC) was effective for evaluating the oxidation of EPA and DHA. During boiling, oxidation of EPA and DHA in the FFA and PC fractions and hydrolysis of the fatty acids at the sn-2 position of the PLs were predominant. The changes in PC during drying were mainly attributed to the oxidation of EPA and DHA. Heat treatment increased the oxidation products and concentration of hydrophobic pyrrole owing to pyrrolization between phosphatidylethanolamine (PE) and the lipid oxidation products. The lipid oxidation level of Antarctic krill increased after drying, owing to prolonged heating under the severe conditions. This article is protected by copyright. All rights reserved.

  1. Hydrolysis of lactose: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Gekas, V; Lopez-Leiva, M

    1985-02-01

    Lactose is the sugar found in milk and whey. Its hydrolysis to glucose and galactose in milk would solve the problem of milk-intolerant people and in whey it would avoid environmental pollution and offer an interesting possibility of by-product utilization. The prepared sweet syrup has many potential applications in the food industry. Hydrolysis of lactose can be carried out by heating at low pH (acid hydrolysis) or by enzymatic catalysis with the enzyme (lactase or ..beta..-D-galactosidase) either free in solution or immobilized by one of the several enzyme immobilization methods which are abundant in the literature. Selection of the proper method depends on many factors: the nature of substrate, use of the final product, need for sanitary conditions, and, of course, capital and processing costs. 157 references.

  2. SIMULTANEOUS PRETREATMENT OF LIGNOCELLULOSE AND HYDROLYSIS OF STARCH IN MIXTURES TO SUGARS

    Directory of Open Access Journals (Sweden)

    Hamzeh Hoseinpour

    2010-11-01

    Full Text Available Mixtures of starch and lignocelluloses are available in many industrial, agricultural, and municipal wastes and residuals. In this work, dilute sulfuric acid was used for simultaneous pretreatment of lignocellulose and hydrolysis of starch, to obtain a maximum amount of fermentable sugar after enzymatic hydrolysis with cellulase and β-glucosidase. The acid treatment was carried out at 70-150°C with 0-1% (v/v acid concentration and 5-15% (w/v solids concentration for 0-40 minutes. Under the optimum conditions, obtained at 130°C, 1% acid, and 7.5% solids loading for 30 min, the starch was almost completely converted to glucose. However, the acid treatment was not successful for efficient hydrolysis of pure cellulose. A mixture of pine softwood and potato as representatives of lignocellulosic and starch components, respectively, were treated at the optimum conditions for acid hydrolysis of starch. The dilute-acid treatment resulted in 1.2, 60.5, and 23.6% hydrolysis of glucan, xylan, and mannan of pine wood and 67% of potato starch to fermentable sugars. After the acid treatment, the solid residue of the mixture was subjected to enzymatic hydrolysis. The enzymatic hydrolysis under the optimum conditions resulted in conversion of 76% of the glucan in the treated softwood. Therefore, using acid treatment of the mixture is a promising process for pretreatment of wood in addition to the hydrolysis of starch.

  3. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    Energy Technology Data Exchange (ETDEWEB)

    Bae, Hyun Jong; Wi, Seung Gon; Kim, Su Bae; Shin, You Jung; Yi, Ju Hui [Chonnam National University, Bio-Energy Research Institute, Gwangju (Korea, Republic of)

    2010-10-15

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. Research scope includes 1) screening of various microorganisms from decayed biomass in order to search for more efficient lignocellulose degrading microorganism, 2) identification and verification of new cell wall degrading cellulase for application cellulose bioconversion process, and 3) identification and characterization of novel genes involved in cellulose degradation. To find good microorganism candidates for lignocellulose degrading, 75 decayed samples from different areas were assayed in triplicate and analyzed. For cloning new cell wall degrading enzymes, we selected microorganisms because it have very good lignocellulose degradation ability. From that microorganisms, we have apparently cloned a new cellulase genes (10 genes). We are applying the new cloned cellulase genes to characterize in lignocellulsoe degradation that are most important to cellulosic biofuels production

  4. Optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production

    International Nuclear Information System (INIS)

    Bae, Hyun Jong; Wi, Seung Gon; Kim, Su Bae; Shin, You Jung; Yi, Ju Hui

    2010-10-01

    The purpose of this project is optimization of upstream and development of cellulose hydrolysis process for cellulosic bio-ethanol production. Research scope includes 1) screening of various microorganisms from decayed biomass in order to search for more efficient lignocellulose degrading microorganism, 2) identification and verification of new cell wall degrading cellulase for application cellulose bioconversion process, and 3) identification and characterization of novel genes involved in cellulose degradation. To find good microorganism candidates for lignocellulose degrading, 75 decayed samples from different areas were assayed in triplicate and analyzed. For cloning new cell wall degrading enzymes, we selected microorganisms because it have very good lignocellulose degradation ability. From that microorganisms, we have apparently cloned a new cellulase genes (10 genes). We are applying the new cloned cellulase genes to characterize in lignocellulsoe degradation that are most important to cellulosic biofuels production

  5. Real-Time Model Based Process Monitoring of Enzymatic Biodiesel Production

    DEFF Research Database (Denmark)

    Price, Jason Anthony; Nordblad, Mathias; Woodley, John

    2015-01-01

    In this contribution we extend our modelling work on the enzymatic production of biodiesel where we demonstrate the application of a Continuous-Discrete Extended Kalman Filter (a state estimator). The state estimator is used to correct for mismatch between the process data and the process model...... for Fed-batch production of biodiesel. For the three process runs investigated, using a single tuning parameter, qx=2 x 10-2 which represents the uncertainty in the process model, it was possible over the entire course of the reaction to reduce the overall mean and standard deviation of the error between......, there was over a ten-fold decrease in the overall mean error for the state estimator prediction compared with the predictions from the pure model simulations. It is also shown that the state estimator can be used as a tool for detection of outliers in the measurement data. For the enzymatic biodiesel process...

  6. Technical Aspects of Use of Ultrasound for Intensification of Enzymatic Bio-Processing: New Path to "Green Chemistry"

    Science.gov (United States)

    Use of enzymatic processing in the food, textile, and bio-fuel applications is becoming increasingly popular, primarily because of rapid introduction of a new variety of highly efficient enzymes. In general, an enzymatic bio-processing generates less toxic and readily biodegradable wastewater efflue...

  7. Comparative analysis of the effect of pretreating aspen wood with aqueous and aqueous-organic solutions of sulfuric and nitric acid on its reactivity during enzymatic hydrolysis

    DEFF Research Database (Denmark)

    Dotsenko, Gleb; Osipov, D. O.; Zorov, I. N.

    2016-01-01

    The effect of aspen wood pretreatment methods with the use of both aqueous solutions of sulfuric and nitric acids and aqueous-organic solutions (ethanol, butanol) of sulfuric acid (organosolv) on the limiting degree of conversion of this type of raw material into simple sugars during enzymatic...

  8. Enzymatic treatment of paper mill process waters; Entsyymit paperitehtaan kiertoveden kaesittelyssae - EKT 06

    Energy Technology Data Exchange (ETDEWEB)

    Mustranta, A; Buchert, J [VTT Biotechnology and Food Research, Espoo (Finland); Ekman, R; Spetz, P [Aabo Akademi, Turku (Finland). Lab. of Forest Products Chemistry; Luukko, K [Helsinki Univ. of Technology, Otaniemi (Finland). Paper Technology

    1999-12-31

    Dissolved and colloidal substances (DCS) are dispersed into the process waters during different stages of pulp and paper production. These are lipophilic extractives (pitch), hydrophilic extractives (lignan) and carbohydrates, mainly hemicelluloses. These dissolved and colloidal substances accumulate during water circulation and results in impaired paper machine runnability. DCS can also interfere with wet-end process chemicals. In this project the chemical composition of the process waters of spruce TMP pulping have been characterized. Simultaneously, potential enzymes for modification of DCS has been produced and purified. The enzymatic treatments have been started with lipase acting on triglycerides present in extractives. The effect of enzymatic treatment on the properties of process waters and technical properties of the pulp have been evaluated. (orig.)

  9. Enzymatic treatment of paper mill process waters; Entsyymit paperitehtaan kiertoveden kaesittelyssae - EKT 06

    Energy Technology Data Exchange (ETDEWEB)

    Mustranta, A.; Buchert, J. [VTT Biotechnology and Food Research, Espoo (Finland); Ekman, R.; Spetz, P. [Aabo Akademi, Turku (Finland). Lab. of Forest Products Chemistry; Luukko, K. [Helsinki Univ. of Technology, Otaniemi (Finland). Paper Technology

    1998-12-31

    Dissolved and colloidal substances (DCS) are dispersed into the process waters during different stages of pulp and paper production. These are lipophilic extractives (pitch), hydrophilic extractives (lignan) and carbohydrates, mainly hemicelluloses. These dissolved and colloidal substances accumulate during water circulation and results in impaired paper machine runnability. DCS can also interfere with wet-end process chemicals. In this project the chemical composition of the process waters of spruce TMP pulping have been characterized. Simultaneously, potential enzymes for modification of DCS has been produced and purified. The enzymatic treatments have been started with lipase acting on triglycerides present in extractives. The effect of enzymatic treatment on the properties of process waters and technical properties of the pulp have been evaluated. (orig.)

  10. Assessing Reliability of Cellulose Hydrolysis Models to Support Biofuel Process Design – Identifiability and Uncertainty Analysis

    DEFF Research Database (Denmark)

    Sin, Gürkan; Meyer, Anne S.; Gernaey, Krist

    2010-01-01

    The reliability of cellulose hydrolysis models is studied using the NREL model. An identifiability analysis revealed that only 6 out of 26 parameters are identifiable from the available data (typical hydrolysis experiments). Attempting to identify a higher number of parameters (as done in the ori......The reliability of cellulose hydrolysis models is studied using the NREL model. An identifiability analysis revealed that only 6 out of 26 parameters are identifiable from the available data (typical hydrolysis experiments). Attempting to identify a higher number of parameters (as done...

  11. Alkaline hydrolysis process for treatment and disposal of Purex solvent waste

    International Nuclear Information System (INIS)

    Srinivas, C.; Venkatesh, K.A.; Wattal, P.K.; Theyyunni, T.K.; Kartha, P.K.S.; Tripathi, S.C.

    1994-01-01

    Treatment of spent Purex solvent (30% TBP-70% n-dodecane mixture) from reprocessing plants by alkaline hydrolysis process was investigated using inactive 30% TBP solvent as well as actual radioactive spent solvent. Complete conversion of TBP to water-soluble reaction products was achieved in 7 hours reaction time at 130 deg C using 50%(w/v) NaOH solution at NaOH to TBP mole ratio of 3:2. Addition of water to the product mixture resulted in the complete separation of diluent containing less than 2 and 8 Bg./ml. of α and β activity respectively. Silica gel and alumina were found effective for purification of the separated diluent. Aqueous phase containing most of the original radioactivity was found compatible with cement matrix for further conditioning and disposal. (author). 17 refs., 10 tabs., 1 fig

  12. Hydrolysis of solubilized hemicellulose derived from wet-oxidized wheat straw by a mixture of commercial fungal enzyme preparations

    Energy Technology Data Exchange (ETDEWEB)

    Skammelsen Schmidt, Anette; Thomsen, Alle Belinda; Woidemann, Anders [Risoe National Lab. (Denmark); Tenkanen, Maija [VTT Biotechnology and Food Research (Finland)

    1998-04-01

    The enzymatic hydrolysis of the solubilized hemicellulose fraction from wet-oxidized wheat straw was investigated for quantification purposes. An optimal hydrolysis depends on factors such as composition of the applied enzyme mixture and the hydrolysis conditions (enzyme loading, hydrolysis time, pH-value, and temperature). A concentrated enzyme mixture was used in this study prepared at VTT Biotechnology and Food Research, Finland, by mixing four commercial enzyme preparations. No distinctive pH-value and temperature optima were identified after a prolonged incubation of 24 hours. By reducing the hydrolysis time to 2 hours a temperature optimum was found at 50 deg. C, where a pH-value higher than 5.2 resulted in reduced activity. An enzyme-substrate-volume-ratio of 0.042, a pH-value of 5.0, and a temperature of 50 deg. C were chosen as the best hydrolysis conditions due to an improved monosaccharide yield. The hydrolysis time was chosen to be 24 hours to ensure equilibrium and total quantification. Even under the best hydrolysis conditions, the overall sugar yield from the enzymatic hydrolysis was only 85% of that of the optimal acid hydrolysis. The glucose yield were approximately the same for the two types of hydrolyses, probably due to the high cellulase activity in the VTT-enzyme mixture. For xylose and arabinose the enzymatic hydrolysis yielded only 80% of that of the acid hydrolysis. As the pentoses existed mainly as complex polymers their degradation required many different enzymes, some of which might be missing from the VTT-enzyme mixture. Furthermore, the removal of side-choins from the xylan backbone during the wet-oxidation pretreatment process might enable the hemicellulosic polymers to interact and precipitate, hence, reducing the enzymatic digestibility of the hemicellulose. (au) 8 tabs., 10 ills., 65 refs.

  13. Enhanced hydrolysis of cellulose hydrogels by morphological modification.

    Science.gov (United States)

    Alfassi, Gilad; Rein, Dmitry M; Cohen, Yachin

    2017-11-01

    Cellulose is one of the most abundant bio-renewable materials on earth, yet the potential of cellulosic bio-fuels is not fully exploited, primarily due to the high costs of conversion. Hydrogel particles of regenerated cellulose constitute a useful substrate for enzymatic hydrolysis, due to their porous and amorphous structure. This article describes the influence of several structural aspects of the cellulose hydrogel on its hydrolysis. The hydrogel density was shown to be directly proportional to the cellulose concentration in the initial solution, thus affecting its hydrolysis rate. Using high-resolution scanning electron microscopy, we show that the hydrogel particles in aqueous suspension exhibit a dense external surface layer and a more porous internal network. Elimination of the external surface layer accelerated the hydrolysis rate by up to sixfold and rendered the process nearly independent of cellulose concentration. These findings may be of practical relevance to saccharification processing costs, by reducing required solvent quantities and enzyme load.

  14. The Effect of Substrate-Bulk Interaction on Hydrolysis Modeling in Anaerobic Digestion Process

    Directory of Open Access Journals (Sweden)

    Antonio Panico

    2014-11-01

    Full Text Available In an Anaerobic Digestion (AD process treating particulate substrates, the size of solids is expected to negatively affect the rate of hydrolysis step and consequently influence the performance of the whole process. To avoid any disadvantage due to size of solids, expensive pre-treatments aimed at disintegrating and solubilizing substrates are commonly conducted prior to AD. This practice is doubtlessly successful, but not always necessary, since some organic substrates, although particulate, once immersed in water, tend to solubilize immediately. This aspect, if properly considered, could result in saving money and time in the AD process, as well as refining the development and calibration of AD mathematical models. The present study is actually aimed at demonstrating, through experiments and mathematical simulations, different results deriving from the AD process performed, under the same operating conditions, on two different substrates, i.e. homemade pasta and carrot batons, having the same particle size, but different chemical composition and texture. Experimental outcomes highlighted the effect of particles size on bio-methane production only from the bio-methanation potential tests (BMP conducted on carrot batons. Similar results were obtained by mathematical model calibration, i.e., different kinetic constants for differently-sized carrot batons and same kinetic constant for differently-sized homemade pasta solids.

  15. REKAYASA PROSES HIDROLISIS PATI DAN SERAT UBI KAYU (Manihot utilissima UNTUK PRODUKSI BIOETANOL Hydrolysis Process Design of Starch and Cassava (Manihot utilissima Fibers for Bioethanol Production

    Directory of Open Access Journals (Sweden)

    Yuana Susmiati

    2012-05-01

    Full Text Available Ethanol production from cassava (Manihot utilissima usually uses enzymatic process for starch hydrolysis. Enzymatichydrolysis by α-amylase and amyloglucosidase enzymes are not able to convert cassava fibers into sugars. Dilute acid hydrolysis is applied to convert both starch and fibers, which will increase the yield of simple sugars as fermentable sugars and resulting in high ethanol production. In this research there are two steps of dilute acid hydrolysis, first for starch hydrolysis at H SO concentration of 0.1-0.5 M, 5-15 minutes and second for fiber hydrolysis at 0.5-1.0 2 4M H SO , 10-20 minutes, at the same temperature of 121-127 oC and pressure of 1.0-1.5 atm. The disadvantage of acid hydrolysis is the formation of toxic compounds such as hydroxymethyl furfural (HMF which is inhibited yeast fermentation. Therefore, acid hydrolyzates were detoxified with NH OH before use as fermentation substrate. The best starch hydrolysis condition was obtained at 0.4 M H SO  for 10 minutes which gave 257.37 g/l of total sugars, 2 4229.38 g/l of reducing sugars, 89.59 of dextrose equivalent (DE and 0.57 g/l of HMF. While the best fiber hydrolysis performed at 1.0 M H SO  solution for 20 minutes which gave 79.74 g/l of total sugars, 70.88 g/l of reducing sugars, 2 488.99 of DE and 0.0142 g/l of HMF. Single direct acid hydrolysis was the most suitable substrate for yeast fermentationwith the ethanol concentration of 5.7 % (w/v and 30.5 % (w/w of ethanol yield. This result is comparable with enzymatic hydrolysis which gave ethanol yield of 30 % (w/w. ABSTRAK Produksi etanol dari ubi kayu biasanya menggunakan enzim untuk menghidrolisis pati. Hidrolisis secara enzimatismenggunakan enzim α-amilase dan amiloglukosidase tidak mampu mengkonversi serat menjadi gula. Hidrolisis asam  berkonsentrasi  rendah  dilakukan  untuk  mengkonversi  pati  dan  serat,  sehingga  gula-gula  sederhana  yang dapat difermentasi meningkat dan menghasilkan

  16. Modeling evolution of hydrogen bonding and stabilization of transition states in the process of cocaine hydrolysis catalyzed by human butyrylcholinesterase.

    Science.gov (United States)

    Gao, Daquan; Zhan, Chang-Guo

    2006-01-01

    Molecular dynamics (MD) simulations and quantum mechanical/molecular mechanical (QM/MM) calculations were performed on the prereactive enzyme-substrate complex, transition states, intermediates, and product involved in the process of human butyrylcholinesterase (BChE)-catalyzed hydrolysis of (-)-cocaine. The computational results consistently reveal a unique role of the oxyanion hole (consisting of G116, G117, and A199) in BChE-catalyzed hydrolysis of cocaine, compared to acetylcholinesterase (AChE)-catalyzed hydrolysis of acetylcholine. During BChE-catalyzed hydrolysis of cocaine, only G117 has a hydrogen bond with the carbonyl oxygen (O31) of the cocaine benzoyl ester in the prereactive BChE-cocaine complex, and the NH groups of G117 and A199 are hydrogen-bonded with O31 of cocaine in all of the transition states and intermediates. Surprisingly, the NH hydrogen of G116 forms an unexpected hydrogen bond with the carboxyl group of E197 side chain and, therefore, is not available to form a hydrogen bond with O31 of cocaine in the acylation. The NH hydrogen of G116 is only partially available to form a weak hydrogen bond with O31 of cocaine in some structures involved in the deacylation. The change of the estimated hydrogen-bonding energy between the oxyanion hole and O31 of cocaine during the reaction process demonstrates how the protein environment can affect the energy barrier for each step of the BChE-catalyzed hydrolysis of cocaine. These insights concerning the effects of the oxyanion hole on the energy barriers provide valuable clues on how to rationally design BChE mutants with a higher catalytic activity for the hydrolysis of (-)-cocaine. 2005 Wiley-Liss, Inc.

  17. The effect of process conditions on the alpha-amylolytic hydrolysis of amylopectin potato starch : an experimental design approach

    NARCIS (Netherlands)

    Marchal, L.M.; Jonkers, J.; Franke, G.T.; Goooijer, de C.D.; Tramper, J.

    1999-01-01

    The hydrolysis of amylopectin potato starch with Bacillus licheniformis α-amylase (Maxamyl) was studied under industrially relevant conditions (i.e. high dry-weight concentrations). The following ranges of process conditions were chosen and investigated by means of an experimental design: pH [5.6-

  18. Two-dimensional NMR evidence for cleavage of lignin and xylan substituents in wheat straw through hydrothermal pretreatment and enzymatic hydrolysis

    DEFF Research Database (Denmark)

    Yelle, Daniel J.; Kaparaju, Laxmi-Narasimha Prasad; Hunt, Christopher G.

    2013-01-01

    correlation spectroscopy, via an heteronuclear single quantum coherence experiment, revealed substantial lignin β-aryl ether cleavage, deacetylation via cleavage of the natural acetates at the 2-O- and 3-O-positions of xylan, and uronic acid depletion via cleavage of the (1 → 2)-linked 4-O....... g., further deacylation revealed by the depletion in ferulate and p-coumarate structures). Supplementary chemical analyses showed that the hydrothermal pretreatment increased the cellulose and lignin concentration with partial removal of extractives and hemicelluloses. The subsequent enzymatic...

  19. Chemo‐enzymatic epoxidation–process options for improving biocatalytic productivity

    DEFF Research Database (Denmark)

    Hagström, Anna E. V.; Törnvall, Ulrika; Nordblad, Mathias

    2011-01-01

    The reactor choice is crucial when designing a process where inactivation of the biocatalyst is a problem. The main bottleneck for the chemo‐enzymatic epoxidation has been found to be enzyme inactivation by the hydrogen peroxide, H2O2, substrate. In the work reported here, the effect of reaction...... parameters on the reaction performance have been investigated and used to establish suitable operating strategies to minimize the inactivation of the enzyme, using rapeseed methyl ester (RME) as a substrate in a solvent‐free system. The use of a controlled fed‐batch reactor for maintaining H2O2 concentration...... at 1.5 M resulted in increased productivity, up to 76 grams of product per gram of biocatalyst with higher retention of enzyme activity. Further investigation included a multistage design that separated the enzymatic reaction and the saturation of the RME substrate with H2O2 into different vessels...

  20. pH catalyzed pretreatment of corn bran for enhanced enzymatic arabinoxylan degradation

    DEFF Research Database (Denmark)

    Agger, Jane; Johansen, Katja Salomon; Meyer, Anne S.

    2011-01-01

    Corn bran is mainly made up of the pericarp of corn kernels and is a byproduct stream resulting from the wet milling step in corn starch processing. Through statistic modeling this study examined the optimization of pretreatment of corn bran for enzymatic hydrolysis. A low pH pretreatment (pH 2......, 150°C, 65min) boosted the enzymatic release of xylose and glucose and maximized biomass solubilization. With more acidic pretreatment followed by enzymatic hydrolysis the total xylose release was maximized (at pH 1.3) reaching ∼50% by weight of the original amount present in destarched corn bran......, but the enzyme catalyzed xylose release was maximal after pretreatment at approx. pH 2. The total glucose release peaked after pretreatment of approx. pH 1.5 with an enzymatic release of approx. 68% by weight of the original amounts present in destarched corn bran. For arabinose the enzymatic release...

  1. Ultrafast Formation of ZnO Nanorods via Seed-Mediated Microwave Assisted Hydrolysis Process

    International Nuclear Information System (INIS)

    Tan, S T; Yahaya, M; Yap, C C; Umar, A A; Salleh, M M

    2013-01-01

    One dimensional (1D) zinc oxide, ZnO nanostructures have shown promising results for usage in photodiode and optoelectronic device due to their high surface area. Faster and conventional method for synthesis ZnO nanorods has become an attention for researcher today. In this paper, ZnO nanorods have been successfully synthesized via two-step process, namely alcothermal seeding and seed-mediated microwave hydrolysis process. In typical process, the ZnO nanoseeds were grown in the growth solution that contained equimolar (0.04 M) of zinc nitrate hexahydrate, Zn (NO 3 ).6H 2 O and hexamethylenetetramine, HMT. The growth process was carried inside the inverted microwave within 5- 20 s. The effect of growth parameters (i.e. concentration, microwave power, time reaction) upon the modification of ZnO morphology was studied. ZnO nanostructures were characterized by Field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD). The densities of nanorods were evaluated by the Image J analysis. It was found that the morphology (e.g. shape and size) of nanostructures has changed drastically with the increment of growth solution concentration. The density of ZnO nanorods was proven to increase with the increasing of reaction time and microwave power. We hypothesize that the microwave power might enhance the rate of nucleation and promote the faster nanostructure growth as compared with the normal heating condition due to the superheating phenomenon. This method might promote a new and faster alternative way in nanostructure growth which can be applied in currently existing application.

  2. Ultrafast Formation of ZnO Nanorods via Seed-Mediated Microwave Assisted Hydrolysis Process

    Science.gov (United States)

    Tan, S. T.; Umar, A. A.; Yahaya, M.; Yap, C. C.; Salleh, M. M.

    2013-04-01

    One dimensional (1D) zinc oxide, ZnO nanostructures have shown promising results for usage in photodiode and optoelectronic device due to their high surface area. Faster and conventional method for synthesis ZnO nanorods has become an attention for researcher today. In this paper, ZnO nanorods have been successfully synthesized via two-step process, namely alcothermal seeding and seed-mediated microwave hydrolysis process. In typical process, the ZnO nanoseeds were grown in the growth solution that contained equimolar (0.04 M) of zinc nitrate hexahydrate, Zn (NO3).6H2O and hexamethylenetetramine, HMT. The growth process was carried inside the inverted microwave within 5- 20 s. The effect of growth parameters (i.e. concentration, microwave power, time reaction) upon the modification of ZnO morphology was studied. ZnO nanostructures were characterized by Field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD). The densities of nanorods were evaluated by the Image J analysis. It was found that the morphology (e.g. shape and size) of nanostructures has changed drastically with the increment of growth solution concentration. The density of ZnO nanorods was proven to increase with the increasing of reaction time and microwave power. We hypothesize that the microwave power might enhance the rate of nucleation and promote the faster nanostructure growth as compared with the normal heating condition due to the superheating phenomenon. This method might promote a new and faster alternative way in nanostructure growth which can be applied in currently existing application.

  3. Lactose hydrolysis in aqueous two-phase system by whole-cell {beta}-galactosidase of Kluyveromyces marxianus. Semicontinuous and continuous processes

    Energy Technology Data Exchange (ETDEWEB)

    Tomaska, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Stredansky, M [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Tomaskova, A [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology; Sturdik, E [Slovak Technical Univ., Bratislava (Slovakia). Dept. of Biochemical Technology

    1995-01-01

    Semicontinuous and continuous hydrolysis of lactose in aqueous two-phase systems (polyethylene glycol 20000/ dextran 40) with whole-cell {beta}-galactosidase of K. marxianus were studied. Both phase polymers had no effect on {beta}-galactosidase activity confined in cells. Good operational stability of the biocatalyst during 55 cycles of semicontinuous process was observed without appreciable decrease in product concentration. Continuous hydrolysis of lactose was performed in the stirred bioreactor, connected with the phase separator. The satisfactory degree of hydrolysis (between 82-88%) and volumetric productivity (21.6 g/l/h) were reached during 72 hours of continuous hydrolysis of 5% (w/w) lactose. (orig.)

  4. Kinetic and Modeling Investigation to Provide Design Guidelines for the NREL Dilute-Acid Process Aimed at Total Hydrolysis/Fractionation of Lignocellulosic Biomass: July 1998

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Y. Y.; Iyer, P.; Xiang, Q.; Hayes, J.

    2004-08-01

    Following up on previous work, subcontractor investigated three aspects of using NREL ''pretreatment'' technology for total hydrolysis (cellulose as well as hemicellulose) of biomass. Whereas historic hydrolysis of biomass used either dilute acid or concentrated acid technology for hydrolysis of both hemicellulose and cellulose, NREL has been pursuing very dilute acid hydrolysis of hemicellulose followed by enzymatic hydrolysis of cellulose. NREL's countercurrent shrinking-bed reactor design for hemicellulose hydrolysis (pretreatment) has, however, shown promise for total hydrolysis. For the first task, subcontractor developed a mathematical model of the countercurrent shrinking bed reactor operation and, using yellow poplar sawdust as a feedstock, analyzed the effect of: initial solid feeding rate, temperature, acid concentration, acid flow rate, Peclet number (a measure of backmixing in liquid flow), and bed shrinking. For the second task, subcontractor used laboratory trials, with yellow poplar sawdust and 0.07 wt% sulfuric acid at various temperatures, to verify the hydrolysis of cellulose to glucose (desired) and decomposition of glucose (undesired) and determine appropriate parameters for use in kinetic models. Unlike cellulose and hemicellulose, lignins, the third major component of biomass, are not carbohydrates that can be broken down into component sugars. They are, however, aromatic complex amorphous phenolic polymers that can likely be converted into low-molecular weight compounds suitable for production of fuels and chemicals. Oxidative degradation is one pathway for such conversion and hydrogen peroxide would be an attractive reagent for this, as it would leave no residuals. For the third task, subcontractor reacted lignin with hydrogen peroxide under various conditions and analyzed the resulting product mix.

  5. MILD ALKALINE TREATMENT ACTIVATES SPRUCE WOOD FOR ENZYMATIC PROCESSING: A POSSIBLE STAGE IN BIO-REFINERY PROCESSES

    Directory of Open Access Journals (Sweden)

    Yan Wang

    2011-05-01

    Full Text Available The structure of wood is so compact that enzymes are too large to penetrate into the structure and thereby attack the wood components for modifications that can be valuable for various purposes. Here we present a pretreatment method based on traditional kraft pulping, which opens the wood structure, so that enzymes are able to attack the wood components. To study this kind of chemical pretreatment, spruce wood samples were treated at similar conditions used in kraft cooking at varying intensities (H-factors. To verify if the structure was “opened” for enzymes, the pretreated wood samples were incubated with a cellulolytic culture filtrate, and the released reducing sugar concentration after the enzymatic hydrolysis was measured. The results indicated that un-pretreated wood fibers could not be attacked by the enzymes, but already relatively mild pretreatment was sufficient for letting the culture filtrate attack wood polysaccharides, and more intensive treatments opened the structure further. The mildest treatments did not cause any significant yield losses of lignin (Klason lignin. Some galactogluco-mannans were however lost during the pretreatments. The mechanisms behind the effect and the technical significance of the method are discussed.

  6. Powerful peracetic acid-ionic liquid pretreatment process for the efficient chemical hydrolysis of lignocellulosic biomass.

    Science.gov (United States)

    Uju; Goto, Masahiro; Kamiya, Noriho

    2016-08-01

    The aim of this work was to design a new method for the efficient saccharification of lignocellulosic biomass (LB) using a combination of peracetic acid (PAA) pretreatment with ionic liquid (IL)-HCl hydrolysis. The pretreatment of LBs with PAA disrupted the lignin fractions, enhanced the dissolution of LB and led to a significant increase in the initial rate of the IL-HCl hydrolysis. The pretreatment of Bagasse with PAA prior to its 1-buthyl-3-methylimidazolium chloride ([Bmim][Cl])-HCl hydrolysis, led to an improvement in the cellulose conversion from 20% to 70% in 1.5h. Interestingly, the 1-buthyl-3-methylpyridium chloride ([Bmpy][Cl])-HCl hydrolysis of Bagasse gave a cellulose conversion greater than 80%, with or without the PAA pretreatment. For LB derived from seaweed waste, the cellulose conversion reached 98% in 1h. The strong hydrolysis power of [Bmpy][Cl] was attributed to its ability to transform cellulose I to II, and lowering the degree of polymerization of cellulose. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Enzymatic hydrolysis of oil palm empty fruits bunch fiber using Celluclast® and Accellerase® BG for sugar production

    Science.gov (United States)

    Salleh, Noor Shafryna; Murad, Abdul Munir Abdul

    2016-11-01

    In this work, the ability of commercial Trichoderma reesei cellulases preparation, Celluclast® or in combination with Accellerase®BG β-glucosidase to hydrolyse pretreated oil palm empty fruit bunch (OPEFB) was evaluated. Celluclast® alone hydrolyzed OPEFB to produce 2.41±0.44 mg glucose per gram OPEFB. However, the production of glucose was significantly improved with supplementation of Accellerase®BG (8.12±0.93 mg/g). This result suggested that the endoglucanases and exoglucanases in Celluclast® and β-glucosidase in Accellerase®BG able to work synergistically to increase the production of glucose from OPEFB. In addition, the production of xylose was also improved by 30% when the enzyme mixture was used. The result suggested that the mixture of Celluclast® with Accellerase®BG work synergistically to improve the production of sugars by removing the inhibition by cellobiose for complete cellulose hydrolysis. The production of glucose and xylose from OPEFB wastes showed the potential of this biomass as the source of renewable energy and fine chemicals production in Malaysia.

  8. Generation of dipeptidyl peptidase IV (DPP-IV) inhibitory peptides during the enzymatic hydrolysis of tropical banded cricket (Gryllodes sigillatus) proteins.

    Science.gov (United States)

    Nongonierma, Alice B; Lamoureux, Candice; FitzGerald, Richard J

    2018-01-24

    Tropical banded crickets (Gryllodes sigillatus) were studied for their ability to yield hydrolysates with dipeptidyl peptidase IV (DPP-IV) inhibitory properties. A cricket protein isolate (CPI) was prepared following extraction of the water soluble proteins from G. sigillatus powder (CP). The extraction yield and purity were 20.90 ± 0.35% and 57.0 ± 2.23%, respectively. Endogenous proteinase activities were detected in the CP, which were linked to the significant protein breakdown seen in this sample. Fifteen CPI hydrolysates (H1-H15) were generated with Protamex™ using a design of experiments (DOE) approach combining three parameters, temperature (40, 50 and 60 °C), enzyme to substrate ratio (E : S, 0.50, 1.25 and 2.00% (w/w)) and hydrolysis time (60, 150 and 240 min). The DPP-IV half maximal inhibitory concentrations (IC 50 ) of the CPI hydrolysates ranged from 0.40 ± 0.03/0.40 ± 0.02 (H2/H3) to 1.01 ± 0.07 mg mL -1 (H7). Following simulated gastrointestinal digestion (SGID), the DPP-IV IC 50 of CPI decreased (>3.57 vs. 0.78 ± 0.04 mg mL -1 ) while that of H5 increased (0.47 ± 0.03 vs. 0.71 ± 0.06 mg mL -1 ). This study has demonstrated for the first time that G. sigillatus protein hydrolysates are able to inhibit DPP-IV. The study of these hydrolysates in vivo is needed to evaluate their potential role in glycaemic management.

  9. Development and process optimization of an enzyme membrane reactor for lactose hydrolysis. Entwicklung und verfahrenstechnische Optimierung eines Enzym-Membranreaktors fuer die Hydrolyse von Laktose

    Energy Technology Data Exchange (ETDEWEB)

    Czermak, P

    1990-01-01

    The development and process optimization up to the production stage of a vapour sterilizable hollow-fiber membrane reactor for dialysis is illustrated by the example of enzymatic hydrolysis of lactose. The expected conversion efficiency of the membrane reactor is a function of the mass transfer resistance and by the deviations from the defined hydrodynamic status. The transport/reaction behaviour of membrane reactors is therefore described by a model for real reactors which takes account of the non-linear kinetics of the native enzyme, the real mixing conditions inside the reactor, and the mass transfer through the membrane. A coupled numerical solution is used for the calculations. The reaction kinetics, the mass transfer inside the membrane, the hydrodynamics and the conversion rate are determined experimentally. The model can calculate important design data from selected data of the reaction system. Measurements of conversion rates show that the results obtained with real substances, e.g. milk, are well compatible with the model calculations. (orig.) With 85 figs., 25 tabs.

  10. Removal of enzymatic and fermentation inhibitory compounds from biomass slurries for enhanced biorefinery process efficiencies.

    Science.gov (United States)

    Gurram, Raghu N; Datta, Saurav; Lin, Yupo J; Snyder, Seth W; Menkhaus, Todd J

    2011-09-01

    Within the biorefinery paradigm, many non-monomeric sugar compounds have been shown to be inhibitory to enzymes and microbial organisms that are used for hydrolysis and fermentation. Here, two novel separation technologies, polyelectrolyte polymer adsorption and resin-wafer electrodeionization (RW-EDI), have been evaluated to detoxify a dilute acid pretreated biomass slurry. Results showed that detoxification of a dilute acid pretreated ponderosa pine slurry by sequential polyelectrolyte and RW-EDI treatments was very promising, with significant removal of acetic acid, 5-hydroxymethyl furfural, and furfural (up to 77%, 60%, and 74% removed, respectively) along with >97% removal of sulfuric acid. Removal of these compounds increased the cellulose conversion to 94% and elevated the hydrolysis rate to 0.69 g glucose/L/h. When using Saccharomyces cerevisiae D(5)A for fermentation of detoxified slurry, the process achieved 99% of the maximum theoretical ethanol yield and an ethanol production rate nearly five-times faster than untreated slurry. Copyright © 2011 Elsevier Ltd. All rights reserved.

  11. Topochemical distribution of lignin and hydroxycinnamic acids in sugar-cane cell walls and its correlation with the enzymatic hydrolysis of polysaccharides

    Directory of Open Access Journals (Sweden)

    Koch Gerald

    2011-03-01

    Full Text Available Abstract Background Lignin and hemicelluloses are the major components limiting enzyme infiltration into cell walls. Determination of the topochemical distribution of lignin and aromatics in sugar cane might provide important data on the recalcitrance of specific cells. We used cellular ultraviolet (UV microspectrophotometry (UMSP to topochemically detect lignin and hydroxycinnamic acids in individual fiber, vessel and parenchyma cell walls of untreated and chlorite-treated sugar cane. Internodes, presenting typical vascular bundles and sucrose-storing parenchyma cells, were divided into rind and pith fractions. Results Vascular bundles were more abundant in the rind, whereas parenchyma cells predominated in the pith region. UV measurements of untreated fiber cell walls gave absorbance spectra typical of grass lignin, with a band at 278 nm and a pronounced shoulder at 315 nm, assigned to the presence of hydroxycinnamic acids linked to lignin and/or to arabino-methylglucurono-xylans. The cell walls of vessels had the highest level of lignification, followed by those of fibers and parenchyma. Pith parenchyma cell walls were characterized by very low absorbance values at 278 nm; however, a distinct peak at 315 nm indicated that pith parenchyma cells are not extensively lignified, but contain significant amounts of hydroxycinnamic acids. Cellular UV image profiles scanned with an absorbance intensity maximum of 278 nm identified the pattern of lignin distribution in the individual cell walls, with the highest concentration occurring in the middle lamella and cell corners. Chlorite treatment caused a rapid removal of hydroxycinnamic acids from parenchyma cell walls, whereas the thicker fiber cell walls were delignified only after a long treatment duration (4 hours. Untreated pith samples were promptly hydrolyzed by cellulases, reaching 63% of cellulose conversion after 72 hours of hydrolysis, whereas untreated rind samples achieved only 20

  12. Enzymatic Refining and Cellulose Nanofiber Addition in Papermaking Processes from Recycled and Deinked Slurries

    Directory of Open Access Journals (Sweden)

    Marc Delgado-Aguilar

    2015-07-01

    Full Text Available Recycling and deinking processes cause fiber damage because of hornification phenomena and increased external fibrillation. Mechanical refining has been used for many years to enhance the mechanical properties of paper. Biorefining of pulp using enzymes is receiving increasing interest for energy reduction at the refining step of the paper-making process. Moreover, enzymes have also been used for the enhancement of mechanical properties without affecting the drainage rate. As an alternative to mechanical refining treatment, a combination of an enzymatic treatment and cellulose nanofibril (CNF addition was explored to enhance the mechanical properties of paper. The tests were carried out on a deinked pulp (DIP suspension made of 50% old newspapers (ONP and 50% old magazines (OMG. Various enzyme charges and CNF amounts were added to the mixture of ONP and OMG. All pulps (treated and untreated were characterized from a morphological point of view, and the paper sheets made thereof were mechanically characterized. The combination of the enzymatic treatment with the addition of 3% CNF provided sufficient tensile strength for the paper to be used in high-performance applications.

  13. NIR spectroscopy as a process analytical technology (PAT) tool for monitoring and understanding of a hydrolysis process.

    Science.gov (United States)

    Wu, Zhisheng; Peng, Yanfang; Chen, Wei; Xu, Bing; Ma, Qun; Shi, Xinyuan; Qiao, Yanjiang

    2013-06-01

    The use of near infrared spectroscopy was investigated as a process analytical technology to monitor the amino acids concentration profile during hydrolysis process of Cornu Bubali. A protocol was followed, including outlier selection using relationship plot of residuals versus the leverage level, calibration models using interval partial least squares and synergy interval partial least squares (SiPLS). A strategy of four robust root mean square error of predictions (RMSEP) values have been developed to assess calibration models by means of the desirability index. Furthermore, multivariate quantification limits (MQL) values of the optimum model were determined using two types of error. The SiPLS(3) models for L-proline, L-tyrosine, L-valine, L-phenylalanine and L-lysine provided excellent accuracies with RMSEP values of 0.0915 mg/mL, 0.1605 mg/mL, 0.0515 mg/mL, 0.0586 mg/mL and 0.0613 mg/mL, respectively. The MQL ranged from 90 ppm to 810 ppm, which confirmed that these models can be suitable for most applications. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. High throughput, high resolution enzymatic lithography process: effect of crystallite size, moisture, and enzyme concentration.

    Science.gov (United States)

    Mao, Zhantong; Ganesh, Manoj; Bucaro, Michael; Smolianski, Igor; Gross, Richard A; Lyons, Alan M

    2014-12-08

    By bringing enzymes into contact with predefined regions of a surface, a polymer film can be selectively degraded to form desired patterns that find a variety of applications in biotechnology and electronics. This so-called "enzymatic lithography" is an environmentally friendly process as it does not require actinic radiation or synthetic chemicals to develop the patterns. A significant challenge to using enzymatic lithography has been the need to restrict the mobility of the enzyme in order to maintain control of feature sizes. Previous approaches have resulted in low throughput and were limited to polymer films only a few nanometers thick. In this paper, we demonstrate an enzymatic lithography system based on Candida antartica lipase B (CALB) and poly(ε-caprolactone) (PCL) that can resolve fine-scale features, (<1 μm across) in thick (0.1-2.0 μm) polymer films. A Polymer Pen Lithography (PPL) tool was developed to deposit an aqueous solution of CALB onto a spin-cast PCL film. Immobilization of the enzyme on the polymer surface was monitored using fluorescence microscopy by labeling CALB with FITC. The crystallite size in the PCL films was systematically varied; small crystallites resulted in significantly faster etch rates (20 nm/min) and the ability to resolve smaller features (as fine as 1 μm). The effect of printing conditions and relative humidity during incubation is also presented. Patterns formed in the PCL film were transferred to an underlying copper foil demonstrating a "Green" approach to the fabrication of printed circuit boards.

  15. Design of an embedded inverse-feedforward biomolecular tracking controller for enzymatic reaction processes.

    Science.gov (United States)

    Foo, Mathias; Kim, Jongrae; Sawlekar, Rucha; Bates, Declan G

    2017-04-06

    Feedback control is widely used in chemical engineering to improve the performance and robustness of chemical processes. Feedback controllers require a 'subtractor' that is able to compute the error between the process output and the reference signal. In the case of embedded biomolecular control circuits, subtractors designed using standard chemical reaction network theory can only realise one-sided subtraction, rendering standard controller design approaches inadequate. Here, we show how a biomolecular controller that allows tracking of required changes in the outputs of enzymatic reaction processes can be designed and implemented within the framework of chemical reaction network theory. The controller architecture employs an inversion-based feedforward controller that compensates for the limitations of the one-sided subtractor that generates the error signals for a feedback controller. The proposed approach requires significantly fewer chemical reactions to implement than alternative designs, and should have wide applicability throughout the fields of synthetic biology and biological engineering.

  16. Modeling of the steam hydrolysis in a two-step process for hydrogen production by solar concentrated energy

    Science.gov (United States)

    Valle-Hernández, Julio; Romero-Paredes, Hernando; Pacheco-Reyes, Alejandro

    2017-06-01

    In this paper the simulation of the steam hydrolysis for hydrogen production through the decomposition of cerium oxide is presented. The thermochemical cycle for hydrogen production consists of the endothermic reduction of CeO2 to lower-valence cerium oxide, at high temperature, where concentrated solar energy is used as a source of heat; and of the subsequent steam hydrolysis of the resulting cerium oxide to produce hydrogen. The modeling of endothermic reduction step was presented at the Solar Paces 2015. This work shows the modeling of the exothermic step; the hydrolysis of the cerium oxide (III) to form H2 and the corresponding initial cerium oxide made at lower temperature inside the solar reactor. For this model, three sections of the pipe where the reaction occurs were considered; the steam water inlet, the porous medium and the hydrogen outlet produced. The mathematical model describes the fluid mechanics; mass and energy transfer occurring therein inside the tungsten pipe. Thermochemical process model was simulated in CFD. The results show a temperature distribution in the solar reaction pipe and allow obtaining the fluid dynamics and the heat transfer within the pipe. This work is part of the project "Solar Fuels and Industrial Processes" from the Mexican Center for Innovation in Solar Energy (CEMIE-Sol).

  17. A novel process for synthesis of spherical nanocellulose by controlled hydrolysis of microcrystalline cellulose using anaerobic microbial consortium.

    Science.gov (United States)

    Satyamurthy, P; Vigneshwaran, N

    2013-01-10

    Degradation of cellulose by anaerobic microbial consortium is brought about either by an exocellular process or by secretion of extracellular enzymes. In this work, a novel route for synthesis of nanocellulose is described where in an anaerobic microbial consortium enriched for cellulase producers is used for hydrolysis. Microcrystalline cellulose derived from cotton fibers was subjected to controlled hydrolysis by the anaerobic microbial consortium and the resultant nanocellulose was purified by differential centrifugation technique. The nanocellulose had a bimodal size distribution (43±13 and 119±9 nm) as revealed by atomic force microscopy. A maximum nanocellulose yield of 12.3% was achieved in a span of 7 days. While the conventional process of nanocellulose preparation using 63.5% (w/w) sulfuric acid resulted in the formation of whisker shaped nanocellulose with surface modified by sulfation, controlled hydrolysis by anaerobic microbial consortium yielded spherical nanocellulose also referred to as nano crystalline cellulose (NCC) without any surface modification as evidenced from Fourier transform infrared spectroscopy. Also, it scores over chemo-mechanical production of nanofibrillated cellulose by consuming less energy due to enzyme (cellulase) assisted catalysis. This implies the scope for use of microbial prepared nanocellulose in drug delivery and bio-medical applications requiring bio-compatibility. Copyright © 2012 Elsevier Inc. All rights reserved.

  18. [Effect of Residual Hydrogen Peroxide on Hydrolysis Acidification of Sludge Pretreated by Microwave -H2O2-Alkaline Process].

    Science.gov (United States)

    Jia, Rui-lai; Liu, Ji-bao; Wei, Yuan-song; Cai, Xing

    2015-10-01

    Previous studies have found that in the hydrolysis acidification process, sludge after microwave -H2O2-alkaline (MW-H2O2-OH, pH = 10) pretreatment had an acid production lag due to the residual hydrogen peroxide. In this study, effects of residual hydrogen peroxide after MW-H2O2-OH (pH = 10 or pH = 11) pretreatment on the sludge hydrolysis acidification were investigated through batch experiments. Our results showed that catalase had a higher catalytic efficiency than manganese dioxide for hydrogen peroxide, which could completely degraded hydrogen peroxide within 10 min. During the 8 d of hydrolysis acidification time, both SCOD concentrations and the total VFAs concentrations of four groups were firstly increased and then decreased. The optimized hydrolysis times were 0.5 d for four groups, and the optimized hydrolysis acidification times were 3 d for MW-H2O2-OH (pH = 10) group, MW-H2O2-OH (pH = 10) + catalase group and MW-H2O2-OH (pH = 11) + catalase group. The optimized hydrolysis acidification time for MW-H2O2-OH (pH = 11) group was 4 d. Residual hydrogen peroxide inhibited acid production for sludge after MW-H2O2-OH (pH = 10) pretreatment, resulting in a lag in acidification stage. Compared with MW-H2O2-OH ( pH = 10) pretreatment, MW-H2O2-OH (pH = 11 ) pretreatment released more SCOD by 19.29% and more organic matters, which resulted in the increase of total VFAs production significantly by 84.80% at 5 d of hydrolysis acidification time and MW-H2O2-OH (pH = 11) group could shorten the lag time slightly. Dosing catalase (100 mg x -L(-1)) after the MW-H2O2-OH (pH = 10 or pH = 11) pretreatment not only significantly shortened the lag time (0.5 d) in acidification stage, but also produced more total VFAs by 23.61% and 50.12% in the MW-H2O2-OH (pH = 10) + catalase group and MW-H2O2-OH (pH = 11) + catalase group, compared with MW-H2O2-OH (pH = 10) group at 3d of hydrolysis acidification time. For MW-H2O2-OH (pH = 10) group, MW-H2O2-OH (pH = 10) + catalase group and

  19. Alkali-aided enzymatic viscosity reduction of sugar beet mash for novel bioethanol production process

    International Nuclear Information System (INIS)

    Srichuwong, Sathaporn; Arakane, Mitsuhiro; Fujiwara, Maki; Zhang, Zilian; Takahashi, Hiroyuki; Tokuyasu, Ken

    2010-01-01

    Ethanol fermentation of fresh sugar beet mash (SBM) could give a benefit on reducing energy input for sugar diffusion, juice separation, and water evaporation as used in conventional practices, thus offering promise as a low energy process. Actions of cell-wall degrading enzymes provide a mash with low viscosity, which can be easily fermented to ethanol. However, a several-fold higher enzyme loading was required for viscosity reduction of SBM compared with that of potato mash. In this study, the use of dilute alkali treatment (0.025-0.15 N NaOH, 25 o C, 1 h) in enhancing enzymatic viscosity reduction of SBM was evaluated. The results showed that higher NaOH concentration enhanced demethylation and deacetylation of SBM, resulting in greater performances of the enzymes on reducing viscosity. Efficient enzymatic viscosity reduction of SBM was observed with the 0.1 N NaOH treatment. On the other hand, untreated SBM was highly resistant to viscosity reduction, even though a 20-fold more enzyme loading was used. The resulting mash containing 12-13% (w/v) sucrose yielded 7-8% (v/v) ethanol after 24 h of fermentation (90% efficiency). Accordingly, alkali treatment can be applied for facilitating the use of fresh sugar beet for ethanol production.

  20. Effects of process parameters of various pretreatments on enzymatic hydrolysability of Ceiba pentandra (L.) Gaertn. (Kapok) fibre: A response surface methodology study

    International Nuclear Information System (INIS)

    Tye, Ying Ying; Lee, Keat Teong; Wan Abdullah, Wan Nadiah; Leh, Cheu Peng

    2015-01-01

    Kapok fibre is a promising raw material to produce sugar by enzymatic hydrolysis. In this work, effects of water, acid and alkaline pretreatments on the enzymatic sugar yield were studied through response surface methodology (RSM) and supported by the analysis of chemical compositions and physical structure of the fibre. For water pretreatment, reaction temperature and time were the independent variables while chemical concentration was also used as the third independent variable for acid and alkaline pretreatments. For all pretreatments, the enzymatic hydrolysis conditions were kept constant. The structure of pretreated fibre was also examined using scanning electron microscope (SEM). Results showed that water and acid pretreatments effectively dissolved hemicellulose of the fibre with the latter unveiled better results. The alkaline pretreatment resulted in the highest total glucose yield (g/kg of untreated fibre) as compared to water and acid pretreatments. SEM analysis illustrated that water and acid pretreatments led severe destruction of fibre structure; however, both of these pretreatments exhibited lower enhancement of enzymatic hydrolysability of kapok fibre as compared to that observed in alkaline pretreatment. - Highlights: • Effect of pretreatments on sugar yield was studied by response surface methodology. • Glucose yield was highly related to the chemical compositions of pretreated fibers. • Pretreatments altered the physical structure of kapok fibers. • Enzymatic hydrolysability of fibre was improved the most by alkaline treatment. • Over 94% cellulose of the pretreated fibres was converted to glucose

  1. Enzymatic saccharification of dilute acid pretreated saline crops for fermentable sugar production

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Yi; Zhang, Ruihong [Biological and Agricultural Engineering Department, University of California, Davis One Shields Avenue, Davis, CA 95616 (United States); Pan, Zhongli [Biological and Agricultural Engineering Department, University of California, Davis One Shields Avenue, Davis, CA 95616 (United States); Processed Foods Research Unit, USDA-ARS-WRRC, 800 Buchanan Street, Albany, CA 94710 (United States); Wang, Donghai [Biological and Agricultural Engineering Department, Kansas State University, Manhattan, KS 66506 (United States)

    2009-11-15

    Four saline crops [athel (Tamarix aphylla L), eucalyptus (Eucalyptus camaldulensis), Jose Tall Wheatgrass (Agropyron elongatum), and Creeping Wild Ryegrass (Leymus triticoides)] that are used in farms for salt uptake from soil and drainage irrigation water have the potential for fuel ethanol production because they don't take a large number of arable lands. Dilute sulfuric acid pretreatment and enzymatic hydrolysis were conducted to select the optimum pretreatment conditions and the best saline crop for further enzymatic hydrolysis research. The optimum dilute acid pretreatment conditions included T = 165 C, t = 8 min, and sulfuric acid concentration 1.4% (w/w). Creeping Wild Ryegrass was decided to be the best saline crop. Solid loading, cellulase and {beta}-glucosidase concentrations had significant effects on the enzymatic hydrolysis of dilute acid pretreated Creeping Wild Ryegrass. Glucose concentration increased by 36 mg/mL and enzymatic digestibility decreased by 20% when the solid loading increased from 4 to 12%. With 8% solid loading, enzymatic digestibility increased by over 30% with the increase of cellulase concentration from 5 to 15 FPU/g-cellulose. Under given cellulase concentration of 15 FPU/g-cellulose, 60% increase of enzymatic digestibility of pretreated Creeping Wild Ryegrass was obtained with the increase of {beta}-glucosidase concentration up to 15 CBU/g-cellulose. With a high solid loading of 10%, fed-batch operation generated 12% and 18% higher enzymatic digestibility and glucose concentration, respectively, than batch process. (author)

  2. What does the hydrolysis perform in the fermentation of biogas? Biogas, hydrolysis, fermenter biology, multistage process operation; Was kann die Hydrolyse bei der Biogasvergaerung leisten? Biogas, Hydrolyse, Fermenterbiologie, mehrphasige Prozessfuehrung

    Energy Technology Data Exchange (ETDEWEB)

    Oechsner, H.; Lemmer, A. [Landesanstalt fuer Agrartechnik und Bioenergie, Univ. Hohenheim, Stuttgart (Germany)

    2009-07-01

    Nowadays renewable primary products are normally favored for fermentation in agricultural biogas plants. Since this substrate has to be cultivated for biogas fermentation in particular and hence causes production costs, the energy content of the material should be dissipated in biogas completely. For this the fermentation process has to run as efficient as possible. In case of one-phase process management with high space loading there is a risk of imbalance and maybe even collapse of process biology in the fermenter. In case of high space loading and short retention time the substrate won't be fermented completely. The aim is to create good conditions for microorganism participating in the process by a two-phase process management which integrates a stage of hydrolysis. In the stage of hydrolysis the microorganisms and enzymes metabolize the organic matter into readily biodegradable carbonic acids, which can be supplied targeted in the following methanisation as substrate for methanogenic bacteria. The hydrolysis proceeds under various terms and conditions (aerobic/anaerobic, different pH-value, different temperature level). This necessitates a safe control of operation and process parameters, which is often difficult to ensure in practice. In a malfunctioning hydrolysis also methane can be produced, that causes energy losses and environmental damage when emitted in atmosphere. Hydrogen can be produced in the hydrolysis as well what can involve a safety risk. Urgent need for research exists concerning the two-phase fermentation of renewable primary products. By systematic laboratory analysis the knowledge should be expanded, to improve the planning reliability in this field. (orig.)

  3. Two-Dimensional NMR Evidence for Cleavage of Lignin and Xylan Substituents in Wheat Straw Through Hydrothermal Pretreatment and Enzymatic Hydrolysis

    Science.gov (United States)

    Daniel J. Yelle; Prasad Kaparaju; Christopher G. Hunt; Kolby Hirth; Hoon Kim; John Ralph; Claus Felby

    2012-01-01

    Solution-state two-dimensional (2D) nuclear magnetic resonance (NMR) spectroscopy of plant cell walls is a powerful tool for characterizing changes in cell wall chemistry during the hydrothermal pretreatment process of wheat straw for second-generation bioethanol production. One-bond 13C-1H NMR correlation spectroscopy, via...

  4. A one bath chemo-enzymatic process for preparation of absorbent cotton

    Directory of Open Access Journals (Sweden)

    A.S.M. Raja

    2016-09-01

    Full Text Available Cotton is the raw material for preparation of absorbent cotton. Raw cotton has to be subjected to scouring and bleaching processes for making it absorbent by removing the naturally present wax, protein and minerals in the fibre. The scouring is done at 115 °C using alkali followed by bleaching at boiling condition using alkaline hydrogen peroxide solution. The effluent coming out of such processes contains high COD and BOD values. Due to the stringent environmental regulation and great awareness among the public about environment, worldwide attempts have been made to develop green and sustainable chemical processing of materials. Based on the above, in the present study efforts have been made to develop an eco-friendly one bath preparatory process for the production of absorbent cotton using chemo-enzymatic formulation. The result indicated that absorbent cotton produced using the developed process fulfilled the required performance properties as per pharmacopoeia in comparable with the conventional process made one.

  5. Electron beam combined with hydrothermal treatment for enhancing the enzymatic convertibility of sugarcane bagasse

    International Nuclear Information System (INIS)

    Duarte, C.L.; Ribeiro, M.A.; Oikawa, H.; Mori, M.N.; Napolitano, C.M.; Galvão, C.A.

    2012-01-01

    The use of microbial cellulolytic enzymes is the most efficient process to liberate glucose from cellulose in biomass without the formation of fermentation inhibitors. A combination of pretreatment technologies is an alternative way to increase the access of enzymes to cellulose, and consequently, the conversion yield. In this way, the present study reports on the enzymatic hydrolysis of SCB submitted to three kinds of pretreatment: electron beam processing (EBP), and EBP followed by hydrothermal (TH) and diluted acid (AH) treatment. SCB samples were irradiated using a radiation dynamics electron beam accelerator, and then submitted to thermal and acid (0.1% sulfuric acid) hydrolysis for 40 and 60 min at 180 °C. These samples were submitted to enzymatic hydrolysis (EH) using commercial preparations, including Celluclast 1.5 L and beta-glycosidase. The addition of diluted acid improved TH treatment allowing for a shorter application time. EBP with 50 kGy increased the enzymatic hydrolysis yield of cellulose by 20% after TH and 30% after AH. - Highlights: ► We study the enzymatic hydrolysis of cellulose and hemicellulose in sugarcane bagasse. ► We study the combination of three pretreatments: electron beam processing, EBP followed by hydrothermal and by diluted acid treatment. ► The electron beam processing increased the enzymatic hydrolysis from 8% to 15% with 20 kGy. ► The enzymes used were commercial preparations, as Celluclast 1.5 L and β-glycosidase. ► The EBP with 50 kGy increased on 20% the yield of EH of cellulose after TH and 30% after AH.

  6. Antioxidant and Anti-Inflammatory Activities of Hydrolysates and Peptide Fractions Obtained by Enzymatic Hydrolysis of Selected Heat-Treated Edible Insects

    OpenAIRE

    Zielińska, Ewelina; Baraniak, Barbara; Karaś, Monika

    2017-01-01

    This study investigated the effect of heat treatment of edible insects on antioxidant and anti-inflammatory activities of peptides obtained by in vitro gastrointestinal digestion and absorption process thereof. The antioxidant potential of edible insect hydrolysates was determined as free radical-scavenging activity, ion chelating activity, and reducing power, whereas the anti-inflammatory activity was expressed as lipoxygenase and cyclooxygenase-2 inhibitory activity. The highest antiradical...

  7. Effect of gelatinization and hydrolysis conditions on the selectivity of starch hydrolysis with alpha-amylase from Bacillus licheniformis

    NARCIS (Netherlands)

    Baks, T.; Bruins, M.E.; Matser, A.M.; Janssen, A.E.M.; Boom, R.M.

    2008-01-01

    Enzymatic hydrolysis of starch can be used to obtain various valuable hydrolyzates with different compositions. The effects of starch pretreatment, enzyme addition point, and hydrolysis conditions on the hydrolyzate composition and reaction rate during wheat starch hydrolysis with ¿-amylase from

  8. Kinetics of cellobiose hydrolysis using cellobiase composites from Trichoderma reesei and Aspergillus niger

    Energy Technology Data Exchange (ETDEWEB)

    Grous, W.; Converse, A.; Grethlein, H.; Lynd, L.

    1985-01-01

    The enzymatic hydrolysis of cellulose to glucose involves the formation of cellobiose as an intermediate. It has been found necessary to add cellobiase from Aspergillus niger (NOVO) to the cellobiase component of Trichoderma reesei mutant Rut C-30 (Natick) cellulase enzymes in order to obtain after 48 h complete conversion of the cellobiose formed in the enzymatic hydrolysis of biomass. This study of the cellobiase activity of these two enzyme sources was undertaken as a first step in the formation of a kinetic model for cellulose hydrolysis that can be used in process design. In order to cover the full range of cellobiose concentrations, it was necessary to develop separate kinetic parameters for high- and low-concentration ranges of cellobiose for the enzymes from each organism. Competitive glucose inhibition was observed with the enzymes from both organisms. Substrate inhibition was observed only with the A. niger enzymes.

  9. Robust enzymatic hydrolysis of Formiline-pretreated oil palm empty fruit bunches (EFB) for efficient conversion of polysaccharide to sugars and ethanol.

    Science.gov (United States)

    Cui, Xingkai; Zhao, Xuebing; Zeng, Jing; Loh, Soh Kheang; Choo, Yuen May; Liu, Dehua

    2014-08-01

    Oil palm empty fruit bunch (EFB) was pretreated by Formiline process to overcome biomass recalcitrance and obtain hemicellulosic syrup and lignin. Higher formic acid concentration led to more lignin removal but also higher degree of cellulose formylation. Cellulose digestibility could be well recovered after deformylation with a small amount of lime. After digested by enzyme loading of 15 FPU+10 CBU/g solid for 48 h, the polysaccharide conversion could be over 90%. Simultaneous saccharification and fermentation (SSF) results demonstrated that ethanol concentration reached 83.6 g/L with approximate 85% of theoretic yield when performed at an initial dry solid consistency of 20%. A mass balance showed that via Formiline pretreatment 0.166 kg of ethanol could be produced from 1 kg of dry EFB with co-production of 0.14 kg of high-purity lignin and 5.26 kg hemicellulosic syrup containing 2.8% xylose. Formiline pretreatment thus can be employed as an entry for biorefining of EFB. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. Antioxidant and Anti-Inflammatory Activities of Hydrolysates and Peptide Fractions Obtained by Enzymatic Hydrolysis of Selected Heat-Treated Edible Insects.

    Science.gov (United States)

    Zielińska, Ewelina; Baraniak, Barbara; Karaś, Monika

    2017-09-02

    This study investigated the effect of heat treatment of edible insects on antioxidant and anti-inflammatory activities of peptides obtained by in vitro gastrointestinal digestion and absorption process thereof. The antioxidant potential of edible insect hydrolysates was determined as free radical-scavenging activity, ion chelating activity, and reducing power, whereas the anti-inflammatory activity was expressed as lipoxygenase and cyclooxygenase-2 inhibitory activity. The highest antiradical activity against DPPH • (2,2-diphenyl-1-picrylhydrazyl radical) was noted for a peptide fraction from baked cricket Gryllodes sigillatus hydrolysate (IC 50 value 10.9 µg/mL) and that against ABTS •+ (2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical) was the highest for raw mealworm Tenebrio molitor hydrolysate (inhibitory concentration (IC 50 value) 5.3 µg/mL). The peptides obtained from boiled locust Schistocerca gregaria hydrolysate showed the highest Fe 2+ chelation ability (IC 50 value 2.57 µg/mL); furthermore, the highest reducing power was observed for raw G. sigillatus hydrolysate (0.771). The peptide fraction from a protein preparation from the locust S. gregaria exhibited the most significant lipoxygenase and cyclooxygenase-2 inhibitory activity (IC 50 value 3.13 µg/mL and 5.05 µg/mL, respectively).

  11. Monitoring of soluble starch hydrolysis induced by α-amylase from Aspergillus oryzae using ultrasonic spectroscopy

    Science.gov (United States)

    Sierra, Carlos; Resa, Pablo; Buckin, Vitaly; Elvira, Luis

    2012-05-01

    The online monitoring of enzymatic starch hydrolysis is an important issue for several industrial sectors, mainly in the alimentary industry. Ultrasonic non-invasive methods based on the detection of wave velocity and amplitude changes can be used to study this enzymatic reaction. These wave propagating changes are result of physicalchemical modifications produced in the media by the starch hydrolysis. In this work the starch hydrolysis induced by the enzyme α-amylase from Aspergillus oryzae is studied. This biochemical reaction has been monitored using a high-resolution ultrasonic spectroscopy (HR-US) which is non-invasive and nondestructive. The measured time profiles o of ultrasonic velocity are explained in terms of the starch hydrolysis and the subsequent production of oligosaccharides as a consequence of the enzymatic action. The obtained results have been compared to a conventional off-line technique used in biochemistry, the iodine-starch reaction, a spectrophotometric method to quantify the amount of starch remaining in the medium. The combination of these two types of measurement provides more complete information about the biochemical processes occurred during hydrolysis.

  12. Tuning of Essential Oil Properties by Enzymatic Treatment: Towards Sustainable Processes for the Generation of New Fragrance Ingredients

    Directory of Open Access Journals (Sweden)

    Sylvain Antoniotti

    2014-07-01

    Full Text Available In this review, several strategies of modification of essential oils by enzymatic treatment are presented. Being either applied before or after the production of the essential oil, enzymatic methods are shown to be particularly adapted to attain the required selectivity, specificity and efficiency in sustainable processes delivering products eligible for the natural grade. Examples dealing with the optimization of the properties of essential oils in terms of biological activity, odor and safety are provided, and it is likely that these strategies will address other type of properties in the future, such as the physico-chemical properties, for example.

  13. Enhanced coproduction of hydrogen and methane from cornstalks by a three-stage anaerobic fermentation process integrated with alkaline hydrolysis.

    Science.gov (United States)

    Cheng, Xi-Yu; Liu, Chun-Zhao

    2012-01-01

    A three-stage anaerobic fermentation process including H(2) fermentation I, H(2) fermentation II, methane fermentation was developed for the coproduction of hydrogen and methane from cornstalks. Hydrogen production from cornstalks using direct microbial conversion by Clostridium thermocellum 7072 was markedly enhanced in the two-stage thermophilic hydrogen fermentation process integrated with alkaline treatment. The highest total hydrogen yield from cornstalks in the two-stage fermentation process reached 74.4 mL/g-cornstalk. The hydrogen fermentation effluents and alkaline hydrolyzate were further used for methane fermentation by anaerobic granular sludge, and the total methane yield reached 205.8 mL/g-cornstalk. The total energy recovery in the three-stage anaerobic fermentation process integrated with alkaline hydrolysis reached 70.0%. Copyright © 2011 Elsevier Ltd. All rights reserved.

  14. Elements for optimizing a one-step enzymatic bio-refinery process of shrimp cuticles: Focus on enzymatic proteolysis screening.

    Science.gov (United States)

    Baron, R; Socol, M; Kaas, R; Arhaliass, A; Rodriguez Del Pino, J; Le Roux, K; Donnay-Moreno, C; Bergé, J P

    2017-09-01

    This article complements an earlier work published in 2015 Baron et al. (2015) that showed the interest of a shrimp shells bio-refining process. We compare here the effect of eleven commercial proteases at pH 3.5 or 4.0 on a residual amount of shrimp shells proteins after 6 h at 50 °C. The two pH are obtained when respectively 40 and 25 mmol of formic acid are added to 5 g of mild dried shell. Deproteinisation yield above 95% are obtained. Residual amino acids profile in the solid phase was identical for the eleven proteases except for pepsin which was similar to the raw material profile. A significant relative increase in the proportion of Glycine is observed for the ten other cases. Likewise, shapes of size exclusion chromatograms of the dissolved phase are similar except with pepsin.

  15. Performance and microbial community structures of hydrolysis acidification process treating azo and anthraquinone dyes in different stages.

    Science.gov (United States)

    Liu, Na; Xie, Xuehui; Yang, Bo; Zhang, Qingyun; Yu, Chengzhi; Zheng, Xiulin; Xu, Leyi; Li, Ran; Liu, Jianshe

    2017-01-01

    In this study, performance of hydrolysis acidification process treating simulated dyeing wastewater containing azo and anthraquinone dyes in different stages was investigated. The decolorization ratio, COD Cr removal ratio, BOD 5 /COD Cr value, and volatile fatty acids (VFAs) production were almost better in stage 1 than that in stage 2. Fourier transform infrared spectroscopy (FTIR) and gas chromatography-mass spectrometry (GC-MS) confirmed the biodegradation of Reactive Black 5 (RB5) and Remazol Brilliant Blue R (RBBR) in hydrolysis acidification process. Polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) analyses revealed that significant difference of microbial community structures existed in stage 1 and 2. The dominant species in stage 1 was related to Bacteroidetes group, while the dominant species in stage 2 was related to Bacteroidetes and Firmicutes groups. From the results, it could be speculated that different dyes' structures might have significant influence on the existence and function of different bacterial species, which might supply information for bacteria screening and acclimation in the treatment of actual dyeing wastewater.

  16. Enzymatic hydrolysis of the fish oil

    OpenAIRE

    Padilha, Márcia Elisa da Silva; Augusto-Ruiz, Walter

    2007-01-01

    O óleo de pescado tem sido alvo de várias pesquisas em função dos benefícios nutricionais dos ácidos graxos poliinsaturados. Esse fato pode ser comprovado pelos estudos epidemiológicos que relacionam a baixa incidência de doenças cardiovasculares com o consumo de ácidos graxos n-3 (EPA-eicosapentaenóico e DHA-docosahexaenóico) provenientes de peixes marinhos. A obtenção de ácidos graxos poliinsaturados n-3 pode ser realizada por hidrólise enzimática. A hidrólise enzimática de óleos e gorduras...

  17. The In Vitro Effects of Enzymatic Digested Gliadin on the Functionality of the Autophagy Process

    Directory of Open Access Journals (Sweden)

    Federico Manai

    2018-02-01

    Full Text Available Gliadin, the alcohol-soluble protein fraction of wheat, contains the factor toxic for celiac disease (CD, and its toxicity is not reduced by digestion with gastro-pancreatic enzymes. Importantly, it is proved that an innate immunity to gliadin plays a key role in the development of CD. The immune response induces epithelial stress and reprograms intraepithelial lymphocytes into natural killer (NK-like cells, leading to enterocyte apoptosis and an increase in epithelium permeability. In this contribution, we have reported that in Caco-2 cells the administration of enzymatically digested gliadin (PT-gliadin reduced significantly the expression of the autophagy-related marker LC3-II. Furthermore, electron and fluorescent microscope analysis suggested a compromised functionality of the autophagosome apparatus. The rescue of the dysregulated autophagy process, along with a reduction of PT-gliadin toxicity, was obtained with a starvation induction protocol and by 3-methyladenine administration, while rapamycin, a well-known autophagy inducer, did not produce a significant improvement in the clearance of extra- and intra-cellular fluorescent PT-gliadin amount. Altogether, our results highlighted the possible contribution of the autophagy process in the degradation and in the reduction of extra-cellular release of gliadin peptides and suggest novel molecular targets to counteract gliadin-induced toxicity in CD.

  18. Starch hydrolysis modeling: application to fuel ethanol production.

    Science.gov (United States)

    Murthy, Ganti S; Johnston, David B; Rausch, Kent D; Tumbleson, M E; Singh, Vijay

    2011-09-01

    Efficiency of the starch hydrolysis in the dry grind corn process is a determining factor for overall conversion of starch to ethanol. A model, based on a molecular approach, was developed to simulate structure and hydrolysis of starch. Starch structure was modeled based on a cluster model of amylopectin. Enzymatic hydrolysis of amylose and amylopectin was modeled using a Monte Carlo simulation method. The model included the effects of process variables such as temperature, pH, enzyme activity and enzyme dose. Pure starches from wet milled waxy and high-amylose corn hybrids and ground yellow dent corn were hydrolyzed to validate the model. Standard deviations in the model predictions for glucose concentration and DE values after saccharification were less than ± 0.15% (w/v) and ± 0.35%, respectively. Correlation coefficients for model predictions and experimental values were 0.60 and 0.91 for liquefaction and 0.84 and 0.71 for saccharification of amylose and amylopectin, respectively. Model predictions for glucose (R2 = 0.69-0.79) and DP4+ (R2 = 0.8-0.68) were more accurate than the maltotriose and maltose for hydrolysis of high-amylose and waxy corn starch. For yellow dent corn, simulation predictions for glucose were accurate (R2 > 0.73) indicating that the model can be used to predict the glucose concentrations during starch hydrolysis.

  19. A comparison of product yields and inorganic content in process streams following thermal hydrolysis and hydrothermal processing of microalgae, manure and digestate.

    Science.gov (United States)

    Ekpo, U; Ross, A B; Camargo-Valero, M A; Williams, P T

    2016-01-01

    Thermal hydrolysis and hydrothermal processing show promise for converting biomass into higher energy density fuels. Both approaches facilitate the extraction of inorganics into the aqueous product. This study compares the behaviour of microalgae, digestate, swine and chicken manure by thermal hydrolysis and hydrothermal processing at increasing process severity. Thermal hydrolysis was performed at 170°C, hydrothermal carbonisation (HTC) was performed at 250°C, hydrothermal liquefaction (HTL) was performed at 350°C and supercritical water gasification (SCWG) was performed at 500°C. The level of nitrogen, phosphorus and potassium in the product streams was measured for each feedstock. Nitrogen is present in the aqueous phase as organic-N and NH3-N. The proportion of organic-N is higher at lower temperatures. Extraction of phosphorus is linked to the presence of inorganics such as Ca, Mg and Fe in the feedstock. Microalgae and chicken manure release phosphorus more easily than other feedstocks. Copyright © 2015. Published by Elsevier Ltd.

  20. Study of processes of adsorption, hydrolysis and metabolism of the substrate in sequential reactors for shifts and their mathematical modeling

    International Nuclear Information System (INIS)

    Arango P, C.

    1993-01-01

    In this article the results of the investigation on the processes of adsorption, hydrolysis and consumption of COD (chemical oxygen demand) in both aerobic and anaerobic reactors to laboratory scale, their relationship with the conditions of illumination, half of support and concentration of oxygen, and their possible application in aerobic post-treatment of anaerobic leachates are presented. The investigation consists of an experimental assembly and a theoretical development of search of descriptor equations of the global process, and rates of occurrence of the particular processes. The experimental assembly was carried out with four reactors to laboratory scale subjected to different conditions of light, half of support and concentration of oxygen; it had two phases: one of evaluation of the effect of the different conditions in the efficiency of the reactors, and another of evaluation of the kinetic constants in the reactor of better acting and their application in aerobic treatment of anaerobic leachates