scholarly journals Co-production of Xylooligosaccharides and Xylose From Poplar Sawdust by Recombinant Endo-1,4-β-Xylanase and β-Xylosidase Mixture Hydrolysis

2021 ◽  
Vol 8 ◽  
Author(s):  
Qi Li ◽  
Yunpeng Jiang ◽  
Xinyi Tong ◽  
Linguo Zhao ◽  
Jianjun Pei
Keyword(s):  
Enzymatic Hydrolysis ◽  
Deep Understanding ◽  
Important Application ◽  
Raw Material ◽  
Hydrolysis Yield ◽  
Wood Polysaccharides ◽  
Optimized Conditions ◽  
Rate Limiting ◽  
Hydrolysis Of ◽  
Poplar Sawdust

As is well-known, endo-1,4-β-xylanase and β-xylosidase are the rate-limiting enzymes in the degradation of xylan (the major hemicellulosic component), main functions of which are cleavaging xylan to release xylooligosaccharides (XOS) and xylose that these two compounds have important application value in fuel, food, and other industries. This study focuses on enzymatic hydrolysis of poplar sawdust xylan for production of XOS and xylose by a GH11 endo-1,4-β-xylanase MxynB-8 and a GH39 β-xylosidase Xln-DT. MxynB-8 showed excellent ability to hydrolyze hemicellulose of broadleaf plants, such as poplar. Under optimized conditions (50°C, pH 6.0, dosage of 500 U/g, substrate concentration of 2 mg/mL), the final XOS yield was 85.5%, and the content of XOS2−3 reached 93.9% after 18 h. The enzymatic efficiency by MxynB-8 based on the poplar sawdust xylan in the raw material was 30.5%. Xln-DT showed excellent xylose/glucose/arabinose tolerance, which is applied as a candidate to apply in degradation of hemicellulose. In addition, the process and enzymatic mode of poplar sawdust xylan with MxynB-8 and Xln-DT were investigated. The results showed that the enzymatic hydrolysis yield of poplar sawdust xylan was improved by adding Xln-DT, and a xylose-rich hydrolysate could be obtained at high purity, with the xylose yield of 89.9%. The enzymatic hydrolysis yield was higher (32.2%) by using MxynB-8 and Xln-DT together. This study provides a deep understanding of double-enzyme synergetic enzymolysis of wood polysaccharides to valuable products.

Improving the efficiency of enzymatic hydrolysis of Eucalyptus residues with a modified aqueous ammonia soaking method

2018 ◽  
Vol 33 (2) ◽  
pp. 165-174 ◽  
Author(s):  
Dan Huo ◽  
Qiulin Yang ◽  
Guigan Fang ◽  
Qiujuan Liu ◽  
Chuanling Si ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Enzymatic Hydrolysis ◽  
Aqueous Ammonia ◽  
Pulp Mill ◽  
Fiber Surface ◽  
Raw Material ◽  
Sem Images ◽  
Aqueous Ammonia Soaking ◽  
Guaiacyl Lignin ◽  
Hydrolysis Of

Abstract Eucalyptus residues from pulp mill were pretreated with aqueous ammonia soaking (AAS) method to improve the efficiency of enzymatic hydrolysis. The optimized condition of AAS was obtained by response surface methodology. Meanwhile, hydrogen peroxide was introduced into the AAS system to modify the AAS pretreatment (AASP). The results showed that a fermentable sugar yield of 64.96 % was obtained when the eucalypt fibers were pretreated at the optimal conditions, with 80 % of ammonia (w/w) for 11 h and keeping the temperature at 90 °C. In further research it was found that the addition of H2O2 to the AAS could improve the pretreatment efficiency. The delignification rate and enzymatic digestibility were increased to 64.49 % and 73.85 %, respectively, with 5 % of hydrogen peroxide being used. FTIR analysis indicated that most syringyl and guaiacyl lignin and a trace amount of xylan were degraded and dissolved during the AAS and AASP pretreatments. The CrI of the raw material was increased after AAS and AASP pretreatments, which was attributed to the removal of amorphous portion. SEM images showed that microfibers were separated and explored from the initial fiber structure after AAS pretreatment, and the AASP method could improve the destructiveness of the fiber surface.

Optimization of steam pretreatment conditions for enzymatic hydrolysis of poplar wood

Holzforschung ◽  
2011 ◽  
Vol 65 (4) ◽  
Author(s):  
Fokko Schütt ◽  
Jürgen Puls ◽  
Bodo Saake
Keyword(s):  
Enzymatic Hydrolysis ◽  
Raw Material ◽  
Steam Pretreatment ◽  
Alkaline Extraction ◽  
Poplar Wood ◽  
Steam Refining ◽  
Severity Factor ◽  
Short Rotation ◽  
Pretreatment Conditions ◽  
Hydrolysis Of

Abstract Steam refining was investigated as a pretreatment for enzymatic hydrolysis of poplar wood from a short rotation plantation. The experiments were carried out without debarking to use an economically realistic raw material. Steam refining conditions were varied in the range of 3–30 min and 170–220°C, according to a factorial design created with the software JMP from SAS Institute Inc., Cary, NC, USA. Predicted steaming conditions for highest glucose and xylose yields after enzymatic hydrolysis were at 210°C and 15 min. Control tests under the optimized conditions verified the predicted results. Further pretreatments without bark showed that the enzymes were not significantly inhibited by the bark. The yield of glucose and xylose was 61.9% of theoretical for the experiments with the whole raw material, whereas the yield for the experiments without bark was 63.6%. Alkaline extraction of lignin from the fibers before enzymatic hydrolysis resulted in an increase of glucose yields from mild pretreated fibers and a decrease for severe pretreated fibers. The extracted lignin had a high content of xylose of up to 14% after very mild pretreatments. On the other hand, molecular weights of the extracted lignin increased substantially after pretreatments with a severity factor above 4. Hence, alkaline extraction of the lignin seems only attractive in a narrow range of steaming conditions.

Optimization of olive pomace enzymatic hydrolysis for fermentable sugar production

2016 ◽  
Vol 46 (6) ◽  
pp. 778-790 ◽  
Author(s):  
Ghassan Abo Chameh ◽  
Fadi Kheder ◽  
Francois Karabet
Keyword(s):  
Enzymatic Hydrolysis ◽  
Ph Value ◽  
Maximum Yield ◽  
Olive Pomace ◽  
Mixing Rate ◽  
Content Type ◽  
Hydrolysis Yield ◽  
Pretreatment Time ◽  
Hydrolysis Conditions ◽  
Hydrolysis Of

Purpose The purpose of this paper was to find out the appropriate enzymatic hydrolysis conditions of alkali pretreated olive pomace (OP) which enable maximum yield of reducing sugar. Design/methodology/approach The commercial enzymatic preparation (Viscozyme® L) was used for the hydrolysis of OP. The effects of pretreatment, time, temperature, pH, enzyme quantity and substrate loading on the hydrolysis yield were investigated. Findings This study showed that enzymatic hydrolysis of OP using Viscozyme® L can be successfully performed at 50°C. Alkaline pretreatment step of OP prior the enzymatic hydrolysis was indispensable. The hydrolysis yield of alkaline pretreated OP was 2.6 times higher than the hydrolysis yield of untreated OP. Highest hydrolysis yield (33.5 ± 1.5 per cent) was achieved after 24 h using 1 per cent (w/v) OP load in the presence of 100 μl Viscozyme® L at 50°C and pH 5.5 with mixing rate of 100 rpm (p = 0.05). Originality/value Reaction time, temperature, pH value and enzyme quantity were found to have a significant effect on enzymatic hydrolysis yield of alkali pretreated of OP. Although high-solid loadings of OP lowered the hydrolysis yield, it produced higher concentration of reducing sugars, which may render the OP conversion process more economically feasible.

scholarly journals Enzymatic sugar production from elephant grass and reed straw through pretreatments and hydrolysis with addition of thioredoxin-His-S

2019 ◽  
Vol 12 (1) ◽  
Author(s):  
Xianqin Lu ◽  
Can Li ◽  
Shengkui Zhang ◽  
Xiaohan Wang ◽  
Wenqing Zhang ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Pennisetum Purpureum ◽  
Commercial Application ◽  
Hydrolysis Lignin ◽  
Cellulose Content ◽  
Sugar Production ◽  
Elephant Grass ◽  
Reed Straw ◽  
Hydrolysis Yield ◽  
Hydrolysis Of

Abstract Background The bioconversion of lignocellulose to fermentable C5/C6-saccharides is composed of pretreatment and enzymatic hydrolysis. Lignin, as one of the main components, resists lignocellulose to be bio-digested. Alkali and organosolv treatments were reported to be able to delignify feedstocks and loose lignocellulose structure. In addition, the use of additives was an alternative way to block lignin and reduce the binding of cellulases to lignin during hydrolysis. However, the relatively high cost of these additives limits their commercial application. Results This study explored the feasibility of using elephant grass (Pennisetum purpureum) and reed straw (Phragmites australis), both of which are important fibrous plants with high biomass, no-occupation of cultivated land, and soil phytoremediation, as feedstocks for bio-saccharification. Compared with typical agricultural residues, elephant grass and reed straw contained high contents of cellulose and hemicellulose. However, lignin droplets on the surface of elephant grass and the high lignin content in reed straw limited their hydrolysis performances. High hydrolysis yield was obtained for reed straw after organosolv and alkali pretreatments via increasing cellulose content and removing lignin. However, the hydrolysis of elephant grass was only enhanced by organosolv pretreatment. Further study showed that the addition of bovine serum albumin (BSA) or thioredoxin with His- and S-Tags (Trx-His-S) improved the hydrolysis of alkali-pretreated elephant grass. In particular, Trx-His-S was first used as an additive in lignocellulose saccharification. Its structural and catalytic properties were supposed to be beneficial for enzymatic hydrolysis. Conclusions Elephant grass and reed straw could be used as feedstocks for bioconversion. Organosolv and alkali pretreatments improved their enzymatic sugar production; however, the increase in hydrolysis yield of pretreated elephant grass was not as effective as that of reed straw. During the hydrolysis of alkali-pretreated elephant grass, Trx-His-S performed well as additive, and its structural and catalytic capability was beneficial for enzymatic hydrolysis.

scholarly journals Calcium peroxide pretreatment to facilitate the delignification and enzymatic hydrolysis of wheat straw

2021 ◽  
Author(s):  
Youshan Sun ◽  
Xuyang Zhang ◽  
Fei Wang ◽  
Meiyan Wang
Keyword(s):  
Enzymatic Hydrolysis ◽  
Wheat Straw ◽  
Complex Structure ◽  
Raw Material ◽  
Liquid Ratio ◽  
Enzymatic Digestibility ◽  
Calcium Peroxide ◽  
Glucose Recovery ◽  
Solid Liquid ◽  
Hydrolysis Of

Abstract Calcium peroxide (CaO2) pretreatment was employed to remove lignin and subsequently facilitate enzymatic digestibility of wheat straw. An optimal condition was obtained at 130°C for 10 min with 0.35 g CaO2/g dried material of wheat straw and a 1:8 solid-liquid ratio. Under this condition, 57.8% of initial lignin, 7.2% of initial glucan, and 30.6% of initial xylan were removed from CaO2 pretreatment, respectively, meanwhile, a glucose recovery of 90.6 % and a xylose recovery of 65.9 % were obtained from the subsequent enzymatic hydrolysis of treated wheat straw, respectively. CaO2 pretreatment was proved to be a very effective method in delignification and improving enzymatic digestibility. Compared to raw material, the complex structure of lignocellulose was drastically disrupted with a wide emergence of scaly bulges and fully exposed microfibers, which still retained in the solid.

scholarly journals Optimisation of the Enzymatic Hydrolysis of Blood Cells with a Neutral Protease

2013 ◽  
Vol 2013 ◽  
pp. 1-10 ◽  
Author(s):  
Yanbin Zheng ◽  
Qiushi Chen ◽  
Anshan Shan ◽  
Hao Zhang
Keyword(s):  
Amino Acids ◽  
Enzymatic Hydrolysis ◽  
Incubation Period ◽  
Blood Cells ◽  
Substrate Concentration ◽  
Neutral Protease ◽  
Degree Of Hydrolysis ◽  
Hydrolysis Conditions ◽  
Optimized Conditions ◽  
Hydrolysis Of

For utilizing the blood cells (BCs) effectively, enzymatic hydrolysis was applied to produce the enzymatically hydrolyzed blood cells (EHBCs) by using a neutral protease as a catalyst. The results of the single-factor experiments showed optimal substrate concentration, enzyme to substrate ratio (E/S), pH, temperature, and incubation period were 1.00%, 0.10, 7.00, 50.00°C, and 12.00 h, respectively. The optimized hydrolysis conditions from response surface methodology (RSM) were pH 6.50, E/S 0.11, temperature 45.00°C, and incubation period 12.00 h. Under these conditions (substrate concentration 1.00%), the degree of hydrolysis (DH) was 35.06%. The free amino acids (FAAs) content of the EHBCs (35.24%) was 40.46 times higher than BCs while the total amino acids (TAAs) content was lower than BCs. The scores of lysine (human 0.87; pig 0.97), valine (human 1.42; pig 1.38), leucine (human 1.50; pig 1.90), tyrosine (human 0.84; pig 1.09), and histidine (human 2.17; pig 2.50) indicated that the EHBCs basically fulfilled the adult human and pig nutritional requirements. The calculated protein efficiency ratios (C-PERs) of the EHBCs were 3.94, 6.19, 21.73, and 2.04. In summary, the EHBCs were produced successfully with optimized conditions and could be a novel protein source for humans and pigs.

scholarly journals Enzymatic Hydrolysis of Water Extractable Polysaccharides from Leaves of Plantago major L.

Folia Medica ◽  
2017 ◽  
Vol 59 (2) ◽  
pp. 210-216 ◽  
Author(s):  
Paolina K. Lukova ◽  
Diana P. Karcheva-Bahchevanska ◽  
Veselin P. Bivolarski ◽  
Rumen D. Mladenov ◽  
Ilia N. Iliev ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Degree Of Polymerization ◽  
Hot Water ◽  
Cell Mediated Immunity ◽  
Plantago Major ◽  
Beneficial Effects ◽  
Hydrolysis Yield ◽  
Antiviral Activities ◽  
Hydrolysis Of ◽  
Water Extractable

AbstractBackground:Plantago majorL. leaves have been used for centuries by the traditional medicine in the treatment of infectious disorders of the respiratory, urinary and digestive tracts. Researchers have reported that hot water extracts ofPlantago majorpossess a broad-spectrum of anticancer, antioxidant and antiviral activities, as well as activities which modulate cell-mediated immunity. Their beneficial properties may be due to the significant content of polysaccharides. The polysaccharides that have been isolated from the leaves ofPlantago majorL. have different structures – pectic substances, galactans, arabinogalactans, glucomannans.Aim:The aim of this paper was to study the correlation between the structure of the water extractable polysaccharides isolated fromPlantago majorL. leaves and their enzymatic hydrolysis with different carbohydrate hydrolases.Materials and methods:The hydrolysis reactions were performed with the enzymes hemicellulase and mannanase. Spectrophotometric total reducing sugars assay was used to examine the hydrolysis yield. The monosaccharide and oligosaccharide compositions were determined using HPLC analysis.Results:The highest hydrolysis yield of the water extractable polysaccharides fromPlantago majorleaves was obtained by treatment with hemicellulase. The hydrolysis yield increased with the augmentation of the ratio of enzyme to polysaccharide. Galactose was the prevalent monosaccharide identified in the composition of the isolated polysaccharides. Oligosaccharides with different degree of polymerization were also detected.Conclusion:The enzymatic hydrolysis of water extractable polysaccharides fromPlantago majorleaves allows us to obtain different types of oligosaccharides with beneficial effects on both human health and industry.

scholarly journals Optimized Conditions for the Enzymatic Hydrolysis of α-Hydroxytriazolam-Glucuronide in Human Urine

2004 ◽  
Vol 50 (3) ◽  
pp. 286-289 ◽  
Author(s):  
Kenji Tsujikawa ◽  
Kenji Kuwayama ◽  
Tatsuyuki Kanamori ◽  
Yuko Iwata ◽  
Yoshihito Ohmae ◽  
...  
Keyword(s):  
Enzymatic Hydrolysis ◽  
Human Urine ◽  
Optimized Conditions ◽  
Hydrolysis Of

Research on Pretreatment Process and Product Detection in Enzymatic Hydrolysis of Lignocellulosic Biomass

2012 ◽  
Vol 503-504 ◽  
pp. 190-193
Author(s):  
Jing Jing Zhao ◽  
Hai Yan Yang ◽  
Bo Li ◽  
Fu Ming Chen
Keyword(s):  
Weight Loss ◽  
Enzymatic Hydrolysis ◽  
Lignocellulosic Biomass ◽  
Dilute Acid Pretreatment ◽  
Dilute Acid ◽  
Acid Pretreatment ◽  
Positive Correlation ◽  
Hydrolysis Yield ◽  
First Time ◽  
Hydrolysis Of

Sulfite pretreatment was explored in enzymatic hydrolysis of bagasse for the first time, and was compared with dilute acid pretreatment. The results showed that enzymatic hydrolysis yield of bagasse after sulfite treatment was lower than that of the bagasse pretreated with dilute acid. Meanwhile, complexity of sulfite pretreatment and its high cost made it infeasible for industrialized production. Results also showed positive correlation of bagasse pretreatment weight loss to enzymatic hydrolysis yield in dilute acid pretreatment processes, which made substrate weight loss a plausible parameter in pretreatment evaluation.

Evaluation and Optimization of The Factors Affectiing Enzymatic Hydrolysis of Silk Fibroin

2011 ◽  
Vol 399-401 ◽  
pp. 1536-1539
Author(s):  
Lei Zhong ◽  
Bing Lu ◽  
An Ping Liao
Keyword(s):  
Enzymatic Hydrolysis ◽  
Silk Fibroin ◽  
Ph Value ◽  
Enzyme Concentration ◽  
Single Factor ◽  
Orthogonal Experiments ◽  
Hydrolysis Rates ◽  
Enzyme Molecules ◽  
Optimized Conditions ◽  
Hydrolysis Of

Enzymatic hydrolysis of silk fibroin is studied in detail by both single factor experiments and orthogonal experiments. The results of single factor experiments show that enzyme concentration, temperature and pH value have significant effects on the hydrolysis. With the changes of them, the structures of enzyme molecules will also change, which will cause different hydrolysis rates. According to the results of orthogonal experiments, the degree of influence of these three factors can be sorted in descending order: temperature, concentration and then pH value. The optimized conditions of hydrolysis achieved in this paper are enzyme concentration 0.5g/L, temperature 60°C and pH value 8.60.

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