scholarly journals Optimization of Xylanase Production from Aspergillus foetidus in Soybean Residue

2018 ◽  
Vol 2018 ◽  
pp. 1-7 ◽  
Author(s):  
Luana Cunha ◽  
Raquel Martarello ◽  
Paula Monteiro de Souza ◽  
Marcela Medeiros de Freitas ◽  
Kleber Vanio Gomes Barros ◽  
...  

Enzymatic hydrolysis is an important but expensive step in the process to obtain enzyme derived products. Thus, the production of efficient enzymes is of great interest for this biotechnological application. The production of xylanase by Aspergillus foetidus in soybean residues was optimized using 2×23 factorial designs. The experimental data was fitted into a polynomial model for xylanase activity. Statistical analyses of the results showed that variables pH and the interaction of pH and temperature had influenced the production of xylanase, with the best xylanase production level (13.98 U/mL) occurring at fermentation for 168 hours, pH 7.0, 28°C, and 120 rpm.

2018 ◽  
Vol 19 (2) ◽  
pp. 117
Author(s):  
Esti Utarti ◽  
S. Siswanto

Hemicellulose is one of lignocellulose waste component, so that xylanase is one of importance enzyme of lignocellulose waste biodegradation. Molds as main decomposer lignosellulose waste has enzyme activities higher than yeast and bacteria. The aim of the research is to find mold that have xylanolitic activity using lignocellulose waste as media production. The research consist of isolations and screening mols from coastal-field of watu Ulo Jember, xylanase production using lignocellulose waste and idntification of mold which has the highes xylanase activity. A total of 66 molds isolated from rice straw in coastal-field of Watu Ulo Jember. There were screened for their xylanase activity. In semiquantitatively screen on Oat Spelt Xylan plate, the result showed that 62 have xilanolytic activities. Based on clearing zone production, isolates ESW A1 (3.2), ESW A5 (3.1), ESW C 16 (3.26), ESW D4 (3.0) and ESW D15 (3.21) have xilanase activity index higher than others. Furthermore, quantitative analysis using wheat bran, rice straw and baggase in basic salt Mandel’s modification media showed that xylanase activity of isolate ESW D4 was higher on rice straw 3% as substrate production with activity 2.66 U/mL. Isolate ESW D4 identified as Aspergillus foetidus so that called as Aspergillus foetidus ESW D4. Keywords: rice straw, coastal-field, Aspergillus foetidus ESW-D


2021 ◽  
Vol 22 (8) ◽  
pp. 4214
Author(s):  
Gautam Anand ◽  
Meirav Leibman-Markus ◽  
Dorin Elkabetz ◽  
Maya Bar

Plants lack a circulating adaptive immune system to protect themselves against pathogens. Therefore, they have evolved an innate immune system based upon complicated and efficient defense mechanisms, either constitutive or inducible. Plant defense responses are triggered by elicitors such as microbe-associated molecular patterns (MAMPs). These components are recognized by pattern recognition receptors (PRRs) which include plant cell surface receptors. Upon recognition, PRRs trigger pattern-triggered immunity (PTI). Ethylene Inducing Xylanase (EIX) is a fungal MAMP protein from the plant-growth-promoting fungi (PGPF)–Trichoderma. It elicits plant defense responses in tobacco (Nicotiana tabacum) and tomato (Solanum lycopersicum), making it an excellent tool in the studies of plant immunity. Xylanases such as EIX are hydrolytic enzymes that act on xylan in hemicellulose. There are two types of xylanases: the endo-1, 4-β-xylanases that hydrolyze within the xylan structure, and the β-d-xylosidases that hydrolyze the ends of the xylan chain. Xylanases are mainly synthesized by fungi and bacteria. Filamentous fungi produce xylanases in high amounts and secrete them in liquid cultures, making them an ideal system for xylanase purification. Here, we describe a method for cost- and yield-effective xylanase production from Trichoderma using wheat bran as a growth substrate. Xylanase produced by this method possessed xylanase activity and immunogenic activity, effectively inducing a hypersensitive response, ethylene biosynthesis, and ROS burst.


2017 ◽  
Vol 30 (11) ◽  
pp. 886-895 ◽  
Author(s):  
Maria Chiara Paccanaro ◽  
Luca Sella ◽  
Carla Castiglioni ◽  
Francesca Giacomello ◽  
Ana Lilia Martínez-Rocha ◽  
...  

Endo-polygalacturonases (PGs) and xylanases have been shown to play an important role during pathogenesis of some fungal pathogens of dicot plants, while their role in monocot pathogens is less defined. Pg1 and xyr1 genes of the wheat pathogen Fusarium graminearum encode the main PG and the major regulator of xylanase production, respectively. Single- and double-disrupted mutants for these genes were obtained to assess their contribution to fungal infection. Compared with wild-type strain, the ∆pg mutant showed a nearly abolished PG activity, slight reduced virulence on soybean seedlings, but no significant difference in disease symptoms on wheat spikes; the ∆xyr mutant was strongly reduced in xylanase activity and moderately reduced in cellulase activity but was as virulent as wild type on both soybean and wheat plants. Consequently, the ΔpgΔxyr double mutant was impaired in xylanase, PG, and cellulase activities but, differently from single mutants, was significantly reduced in virulence on both plants. These findings demonstrate that the concurrent presence of PG, xylanase, and cellulase activities is necessary for full virulence. The observation that the uronides released from wheat cell wall after a F. graminearum PG treatment were largely increased by the fungal xylanases suggests that these enzymes act synergistically in deconstructing the plant cell wall.


2005 ◽  
Vol 127 (1) ◽  
pp. 15-25 ◽  
Author(s):  
Ali A. Pilehvari ◽  
Robert W. Serth

A generalized hydraulic calculation technique is presented that requires, as input, only the raw rheological data for the fluid and the values of the relevant hydraulic parameters. The method utilizes a powerful new rheological model called the Rational Polynomial model, which is capable of accurately representing the rheogram of virtually any time-independent fluid. Predictions of the new method are compared with published experimental data gathered from large-scale flow loops. The tested cases include laminar and turbulent flow for a variety of drilling fluids in both pipes and concentric annuli.


2016 ◽  
Vol 2016 ◽  
pp. 1-7 ◽  
Author(s):  
Guo-Qiang Guan ◽  
Peng-Xiang Zhao ◽  
Jin Zhao ◽  
Mei-Juan Wang ◽  
Shu-Hao Huo ◽  
...  

A new fungusCladosporium oxysporumGQ-3 producing extracellular xylanase was isolated from decaying agricultural waste and identified based on the morphology and comparison of internal transcribed spacer (ITS) rDNA gene sequence.C. oxysporumproduced maximum xylanase activity of 55.92 U/mL with wheat bran as a substrate and NH4Cl as a nitrogen source. Mg2+improvedC. oxysporumxylanase production.Partially purified xylanase exhibited maximum activity at 50°C and pH 8.0, respectively, and showed the stable activity after 2-h treatment in pH 7.0–8.5 or below 55°C. Mg2+enhanced the xylanase activity by 2% while Cu2+had the highest inhibition ratio of 57.9%. Furthermore,C. oxysporumxylanase was resistant to most of tested neutral and alkaline proteases. Our findings indicated thatCladosporium oxysporumGQ-3 was a novel xylanase producer, which could be used in the textile processes or paper/feed industries.


2012 ◽  
Vol 482-484 ◽  
pp. 843-847
Author(s):  
Jia Ling Yao ◽  
Wen Ku Shi ◽  
Jin Feng Lu

The reported mathematical models of magnetorheological (MR) damper cannot make a good tradeoff among reflecting the damper’s nonlinear behavior and controllability. Damping characteristic experiments have been conducted on a MR damper. A composite polynomial model has been proposed integrating the experimental investigation and the polynomial model, in which the plot of polynomial coefficient vs. current is divided into two sections to reflect the property of the current saturation, meanwhile, the affections of exciting amplitude and frequency are considered in this model. The reverse model of the proposed model is easy to be obtained, so it is convenient to realize an open-loop control system to achieve a desirable damping force. The parameters of this model are identified using experimental data in a certain frequency and amplitude, as well as diverse currents. Compared numerical simulation with experimental data, it is verified that the proposed model can accurately predict the damping force without modifying the parameters of the model when frequency, amplitude and current changed.


2015 ◽  
Vol 737 ◽  
pp. 381-387 ◽  
Author(s):  
Mei Zhen Gong ◽  
Rui Huang ◽  
Jin Ling Guo ◽  
Hua Shun Yu ◽  
Juan Yao ◽  
...  

Xylanase has good application prospect in the paper and pulp industry, feed industry, health care and bioenergy industry,etc.The xylanase is one of the key enzyme in the utilization of biomass. Fermentation kinetics equation was constructed based on Logistic and Luedeking-Piret equation. The results showed that the dissolved oxygen was related to the stirring speed, raising to 45% naturally after the log growth phase (about 30h) on the base of the optimum medium process of xylanase production by Trichoderma reesei. Fed-batch fermentation strategy was designed based on fermentation kinetics equations. The xylanase activity was further enhanced to 2406.175U/mL, enzyme activity per unit protein mass was 6573U/mg.


2012 ◽  
Vol 19 ◽  
pp. 7-14
Author(s):  
SCD Sharma ◽  
MS Shovon ◽  
AKM Asaduzzaman ◽  
MG Sarowar Jahan ◽  
T Yeasmin ◽  
...  

Context: To analyze the nutritional and physicochemical parameters for the production of alkali-thermostable and cellulase free xylanase from bacteria. Objectives: The aim of this study was to isolation and identification and of alkali-thermostable and cellulase free xylanase producing bacteria from soil as well as optimization of process parameters for xylanase production. Materials and Methods: The bacterium Bacillus sp. was isolated from soil by serial dilution technique on xylan agar medium and identified by morphological and biochemical studies. The production of xylanase was carried out on xylan broth medium and xylanase activity was assayed by dinitrosalicylic acid (DNS) method. The effect of cultural parameters on the production of xylanase was determined by measuring the activity of xylanase. The effect of temperature and pH on the activity of partially purified xylanase as well as substrate specificity of xylanase were examined. Results: The maximum xylanase production (4000 U/L) by a Bacillus sp. was attained when the medium containing 0.5% wheat bran xylan and peptone at pH 8.0 and 50-55°C within 48-60 h. The partially purified xylanase was optimally active at pH 9.0 and 55°C. The xylanase showed high substrate activity towards wheat bran xylan but no activity towards cellulose, carboxymethyl cellulose and starch. Thus the enzyme was alkali-thermostable and cellulase free xylanase. Conclusion: The results obtained in this study suggest that the Bacillus sp. used is highly potential and useful for the production of cellulase free xylanase. DOI: http://dx.doi.org/10.3329/jbs.v19i0.12994 J. bio-sci. 19: 7-14, 2011


2015 ◽  
Author(s):  
◽  
Venessa Thorulsley

Fermentation processes are vital for the production of numerous bioproducts. Fermentation being the mass culture of micro – organisms for the production of some desired product, is an extensive field, with immense prospects for study and improvement. Enzyme production is of significance as these proteins are biological catalysts, finding niches in numerous industries, xylanase for example is utilized in the pulp and paper, animal feed, biofuel and food production processes. During enzyme production, a critical step is biomass separation, whereby the valuable product, the enzyme, is removed from the broth or micro – biological culture before it is denatured. This is typically achieved via centrifugation. The aim of this study was to develop and evaluate a submerged membrane fermenter system with the specific outcome of increasing the rate of production of xylanase, from the thermophilic fungal species Thermomyces lanuginous DSM 5826. Preliminary shake flask experiments were performed to determine the optimal production conditions, followed by partial characterization of the enzyme. A bioreactor was then fabricated to include a flat sheet membrane module, with outlets for permeate and broth withdrawal and inlets for feed and sterile air input. Experiments were conducted to determine the optimal dilution rate for maximum volumetric productivity. Results from the shake flask experiments indicated that the best conditions for xylanase production, yielding xylanase activity of 5118.60 ± 42.76 U.mL-1 was using nutrient medium containing beechwood xylan (1.5 % w/v), yeast extract (1.5 % w/v), potassium dihydrogen phosphate (0.5 % w/v), adjusted to a pH of 6.5 and inoculated with 1.0 mL of spore solution, rotating in a shaking incubator set to 150 rpm at 50 °C. Apart from analysis of the effect of the carbon source on xylanase activity, coarse corn cobs were used in the shake flask experiments as a cost saving initiative. The pH optima was determined to be 6.5 while the temperature optima of the enzyme was 70 °C. SDS PAGE analysis revealed that the molecular weight of the enzyme was between 25 and 35 kDa and qualitative analysis via a zymogram revealed clear zones of hydrolysis on a xylan infused agarose gel. During short run membrane fermenter experiments the percentage increase in enzyme activity between the batch operation (610.58 ± 34.54 U.mL-1) and semi – continuous operation (981.73 ± 55.54 U.mL-1) with beechwood xylan nutrient replenishment was 60.78 %. The maximum volumetric productivity achieved with beechwood supplementation after 192 hours in semi – continuous operation (5.32 ± 0.30 U.mL-1.hr-1) was 2.1 times greater than that of batch operation (2.54 ± 0.14 U.mL-1.hr-1) which equates to an increase of 110.28 % in productivity measured at its peak. The increase in total activity between batch (610 576.92 U) and beechwood xylan medium supplemented semi – continuous mode (1 184 937.50 U) resulted in a 94.07 % increase. During long run experimental periods, the increase in production of xylanase between the batch (873.26 ± 61.78 U.mL-1) and the xylan medium membrane system (1522.41 ± 107.65 U.mL-1) was determined to be 74.34 % while an overall average increase in productivity between the batch and xylan fed membrane system was 43.25%. The total enzyme activity with in membrane mode with beechwood xylan nutrient medium feed was 160 % greater than the batch process offering a 2.6 – fold increase. Experiments where de – ionized water was alternated with beechwood xylan nutrient medium had no significant impact on the productivity or enzyme activity. The optimal dilution rate for maximum volumetric productivity as determined to be 0.0033 hr-1. The results are indicative of the potential viability of such a design, yielding the desired outcome of a membrane integrated system to significantly increase the production of enzymes during fermentation.


2015 ◽  
Vol 5 (1) ◽  
pp. 559-569 ◽  
Author(s):  
Gabriela Verónica Díaz

The enhanced xylanase production of white rot fungus Irpex lacteus BAFC 1168 strain F using a liquid fermentation culture was investigated. The media nutrients were screened by a Plackett-Burman design and from the analysis of variance, carboxy-methylcellulose, urea and peptone were found to be the most positive and significant nutrient components. Hence, these three variables were selected for further optimization using a five-level central composite design in response surface methodology. The validation of the model experiment was conducted reaching 8.29 U/mL of xylanase activity when the composition medium was 1.6 g/L of CMC, 0.84 g/L of urea and 2 g/L of peptone. Optimum temperature and pH conditions on xylanase activity were also determined using a central composite design. It was reached a maximum xylanase activity of 8.36 U/mL when temperature and pH were 42.8°C and 5.6, respectively.


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