Enzymatic Hydrolysis Temperature Research Articles

Surfactant-modified magnetic CaFe-layered double hydroxide for improving enzymatic saccharification and ethanol production of Artemisia ordosica

The utilization of bio-surfactant rhamnolipid (RL) modified magnetic CaFe-layered double hydroxides (RL-LDH) was successfully carried out to enhance the enzymatic saccharification and ethanol production of Artemisia ordosica (AO). The RL-LDH pretreatment could effectively improve enzymatic hydrolysis of AO. The ethanol yield reached 167.4 mg/g (the reducing sugar yield achieved 540.3 mg/g) when pretreatment pH was 9, RL-LDH to AO mass ratio was 1.5:1, pretreatment time was 1 h, enzymatic hydrolysis temperature was 50 °C, cellulase loading was 50 FPU/g, and simultaneous saccharification and fermentation (SSF) time was 120 h. RL-LDH could stabilize the enzymes and yeast, resulting in increased the reducing sugar and ethanol yields and decreased conversion costs of biofuel. Furthermore, the conversion yields were still higher than that of control group (without RL-LDH) after the RL-LDH was used for 5 times repeatedly. Therefore, utilization of recyclable RL-LDH is promising for future applications in enzymatic hydrolysis and fuel conversion of biomass.

Recovery of Glucose and Polyester from Textile Waste by Enzymatic Hydrolysis

In order to recover glucose and polyester from textile waste, enzymatic hydrolysis of textile waste pretreated by different modification methods was investigated. The effects of key factors related to hydrolysis process were evaluated, including substrate loading, temperature, pH, cellulase dosage, and supplementation of β-glucosidase. Results showed that freezing NaOH/urea could contribute to significant increase of the hydrolysis yield compared with untreated textile waste, from 57.7 to 98.3%. Increasing substrate loading from 1 to 7% (w/v) had a negative effect on glucose recovery yield and significant inhibitory effect was observed over 3% substrate loading. Substrate loading at 3% was selected based on glucose yield. The optimal temperature for enzymatic hydrolysis was 50 °C and significant reduction was observed over 60 °C. There was no significant increase of glucose recovery yield when cellulase loading was over 20 FPU/g and β-glucosidase loading was over 10 U/g. Therefore, the optimum enzymatic hydrolysis condition was using 20 FPU/g cellulase and 10 U/g β-glucosidase at 50 °C and pH 5, based on the criterion for minimizing enzyme dosage and maximizing glucose recovery. The maximum glucose recovery yield of 98.3% was achieved after 96 h hydrolysis.

Research on the Cellulase Hydrolysis of Colocasia Antiquorumin in Producing Ethyl Alcohol

The cellulase hydrolysis experiment in the process of the ethyl alcohol generated by colocasia antiquorum was studied in this paper.Adopting the single factor variable method, three influencing factors (the amount of cellulase, hydrolysis temperature and hydrolysis time) were selected to carry out enzymatic saccharification sugar production tests of pretreated colocasia antiquorums. The results demonstrate that the sugar yield amounts to the maximum (165mg/g) when the enzyme dosage is 0.04g/g, the enzymatic hydrolysis temperature is 45°C, and the reaction time is 48h.

Cobalt-60 gamma-ray irradiation pretreatment and sludge protein for enhancing enzymatic saccharification of hybrid poplar sawdust

In order to improve the enzymatic saccharification of hybrid poplar sawdust, gamma irradiation pretreatment and enzymatic hydrolysis in the presence of sludge protein were investigated. The cellulose crystallinity index were significantly decreased after irradiation pretreatment, and adding sludge protein improved enzyme activity and increased the reducing sugar yield. The conditions of irradiation pretreatment and enzymatic hydrolysis in the presence of sludge protein were systematically examined. The maximum reducing sugar yield was 519mg/g under an irradiation dose of 300kGy, a sludge protein dosage of 2mg/mL, an enzymatic hydrolysis temperature of 45°C, an enzymatic hydrolysis time of 84h, and a 90FPU/g enzyme loading. This work indicated that the combined method of gamma irradiation pretreatment and enzymatic hydrolysis in the presence of sludge protein was a promising potential for the saccharification of hybrid poplar sawdust.

Enzyme-assisted Extraction and Enrichment of Galanthamine from Lycoris aurea

ObjectiveTo explore the optimum condition for complex enzyme-assisted extraction of galanthamine from Lycoris aurea by L9 (34) orthogonal array design and separation effect of cation exchange resin on galanthamine. MethodsCellulase and pectinase solution was used as the extraction solvent. The effects of pH value of enzyme, amount of complex enzyme, dissociation time, and enzymatic hydrolysis temperature on the extraction results were investigated. ResultsThe optimal conditions were obtained as follows: ratio of solid to liquid (g: mL) 1:10, pH value 4.5, amount of complex enzymes 4%, enzymatic hydrolysis temperature 50 °C, and reaction time 2.0 h. Under these conditions, the extraction yield of galanthamine was 0.0294%. In addition, D-001 cation exchange resin was selected for separation of galanthamine. The separation conditions were that adsorption flow rate was 3 BV/h with reagent of pH 2 and the desorption flow rate was 3 BV/h with 70% ethanol solution containing 1.5 mol/L ammonia. After separation, the content of galanthamine was increased to 12.31%. ConclusionThe results provide a reference for industrial production of galanthamine.

Dilute Acid Pretreatment of Oil Palm Trunk Biomass at High Temperature for Enzymatic Hydrolysis

Old oil palm trunk (OPT) is available in large quantity in Southeast Asia and a potential lignocellulosic biomass resource for bioethanol production. Dilute acid (DA) pretreatment was applied to the old oil palm trunk for enzymatic saccharification. The pretreatment conditions were investigated through a fractional factorial experiment design. The pretreated substrates were analyzed for chemical composition, and their enzymatic digestibility was investigated and compared. The results indicated that the DA pretreatment was able to improve enzymatic hydrolysis by removing hemicelluloses from OPT. Mild pretreatment preserved more hemicellulose and cellulose in pretreated OPT, but severe pretreatment was necessary to achieve satisfactory enzymatic hydrolysis of OPT. For example, the DA pretreatment with 3% H2SO4 at 180°C for 40min could achieve an 80% enzymatic hydrolysis.

The Process Conditions of Extracting Polysaccharides from <i>Dendrocalamus latiflorus</i> by Cellulase

The study is focused on the extracting polysaccharide from Dendrocalamus latiflorus with assisted enzyme and cool water to maintain its biological activity. The optimized conditions for the cellulase process are listed as follows The enzymatic hydrolysis temperature stays 50°C. The mass fraction of cellulase (MFC) is 0.4% on the basis of the mass of dry leaves. The volume of water added in is 20mL on the basis of the mass of dry leaves and the pH value of buffer solution remains 4.6. Under these conditions, the ratio of polysaccharides (RP) can be 0.92% after two extractions for 180min in total and its RP is 12.05% higher than the traditional process.

Extraction, characterization and antioxidant activities of polysaccharides from E. corneum gigeriae galli

In the present study, optimization of enzyme-assisted extraction, characterization and antioxidant activities in vitro of polysaccharides from Endothelium corneum gigeriae galli (PEGG) were investigated. It was found that the optimum extraction conditions were determined as follows: extraction temperature 87.0°C, extraction time 177.0min, enzyme concentration 1.65%, enzymatic hydrolysis time 141.0min, liquid-to-solid ratio 20, enzymatic hydrolysis temperature 55°C and enzymatic hydrolysis pH 3.6. Under these conditions, the experimental yield of polysaccharides was 5.08%. In addition, PEGG had a relatively high sulfate radical content. PEGG was composed of rhamnose, fucose, mannose, glucose and galactose, with molar percentages of 13.1, 4.5, 72.8 and 9.6%, respectively. The average molecular weight was 83kDa. And there were infrared characteristic absorption peaks of polysaccharides in the FT-IR spectroscopy of PEGG. For antioxidant activities in vitro, PEGG showed possessed strong hydroxyl radical scavenging, Fe2+ chelating and lipid peroxidation inhibitory activities.

Study on Extracting TB from Liubao Tea with Cellulase Auxiliary Method

A new way using cellulase as auxiliary method to extract theabrownin (TB) from Guangxi Liubao Tea was proposed in this article. Single factor and orthogonal experiments were used to analysis the best extraction condition of TB from Tea. The effects of the enzyme dose, enzymatic hydrolysis time, enzymatic hydrolysis temperature and the PH of extraction were investigated by orthogonal test. Results showed that the order of influence factors was enzymatic hydrolysis time, the PH of extraction, enzyme dose and enzymatic hydrolysis temperature. The optimal extraction conditions were determined as follows: the dosage of cellulose 20 mg/g, the enzymatic hydrolysis time 40 min, the enzymatic hydrolysis temperature 30°C,the extraction PH=4. The highest extraction ration can attach 24.503%.

Study on Optimizate Isolation and Purification Technology of the Reed Ethanol Lignin

Ethanol pulping is a kind of solvent pulping technology. The utilization of lignin in waste liquor can reduce pollution and increase high value of product. The lignin in the waste liquor could be isolated by adding water in the system after standing for several hours and purified by enzymatic and acidic hydrolysis two-step procedure. Results showed that the optimized purification conditions are as follows, enzyme dosage is 0.004g/g (to oven dry lignin), enzymatic buffer pH is 5, enzymatic hydrolysis temperature is 30°C, and hydrochloric acid concentration of acid hydrolysis is 0.055mol/L. The lignin purity is 91.61%, and the yield is 81.89%.

Effect of Temperature on Simultaneous Saccharification and Fermentation of Pretreated Spruce and Arundo

A critical factor in simultaneous saccharification and fermentation (SSF) is the selection of process temperature, which needs to be a compromise between the optimal temperature for enzymatic hydrolysis and that for fermentation. In the present work, isothermal and nonisothermal SSF was experimentally studied using pretreated spruce and arundo materials at a loading of 10% water insoluble solids, with an industrial strain of Saccharomyces cerevisiae as the fermenting organism. In the nonisothermal experiments, the temperatures were linearly increased during the batch time of 96 h, and the results were compared to isothermal SSF operation. The final ethanol concentrations obtained for the arundo material was 16.5 g/L in the nonisothermal process using an initial temperature of 32 degrees C and a linearly increasing temperature of 0.135 degrees C/h. As a comparison, the final ethanol concentration obtained was 13.4 g/L for an isothermal operation at 32 degrees C and 15.3 g/L for an isothermal process running at 39 degrees C. The corresponding values for the spruce material were 33.1 g/L, and 29.1 g/L and 32.2 g/L, for nonisothermal and isothermal operation at 32 and 39 degrees C, respectively. The obtained ethanol yields, in particular for the case of arundo, demonstrate that nonisothermal SSF operation can give increased ethanol yields in comparison to isothermal SSF. (Less)

Cloning of Agarase Gene from Non-Marine Agarolytic Bacterium Cellvibrio sp.

Agarase genes of non-marine agarolytic bacterium Cellvibrio sp. were cloned into Escherichia coli and one of the genes obtained using HindIII was sequenced. From nucleotide and putative amino acid sequences (713 aa, molecular mass; 78,771 Da) of the gene, designated as agarase AgaA, the gene was found to have closest homology to the Saccharophagus degradans (formerly, Microbulbifer degradans) 2-40 aga86 gene, belonging to glycoside hydrolase family 86 (GH86). The putative protein appears to be a non-secreted protein because of the absence of a signal sequence. The recombinant protein was purified with anion exchange and gel filtration columns after ammonium sulfate precipitation and the molecular mass (79 kDa) determined by SDS-PAGE and subsequent enzymography agreed with the estimated value, suggesting that the enzyme is monomeric. The optimal pH and temperature for enzymatic hydrolysis of agarose were 6.5 and 42.5 degrees C, and the enzyme was stable under 40 degrees C. LC-MS and NMR analyses revealed production of a neoagarobiose and a neoagarotetraose with a small amount of a neoagarohexaose during hydrolysis of agarose, indicating that the enzyme is a beta-agarase.