Characterization extrinsic factors of immobilized cells thermoxilanolytic bacteria in producing xylanase (original) (raw)
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Determination of Total Xylanase Activities of Various Thermophilic Bacteria
Journal of the Institute of Science and Technology, 2021
Enzymes, which have important metabolic functions in living organisms, make important contributions to human beings by using them for different purposes in many areas such as economy, food, agriculture, and industry as part of the daily lives. Today, enzymes, whose production and usage purposes, are increasing, were generally obtained from plant, animal, and microorganisms. In this study; the enzyme producing isolates and their total xylanase activities of various thermophilic bacteria (Bacillus coagulans, Bacillus licheniformis, Bacillus subtilis, Bacillus sp. and Geobacillus kaustophilus) isolated from previously hot springs in Eastern and Southeastern Anatolia regions were determined. In the enzyme activity of the isolates, 47 isolates showed xylanase activity less than 0.1 U/ml, 31 isolates were between 0.1 U/ml and 0.2 U/ml. However, 5 isolates of B. subtilis [BTX3 (0.206 U/ml), BTX6 (0.286 U/ml), BTX22 (0.2 U/ml), BTX27 (0.203 U/ml) and BTX32 (0.206 U/ml)] were exhibited highest activity for xylanase enzyme production.
Journal of Biotechnology, 1994
The medium components for the production of extracellular xylanase by Thermoascus aurantiacus was optimized in shake-flask culture using the Box-Wilson method and a central composite design. The traditional one-factor-at-atime method was employed for selecting the effective factors and the initial test range of each ingredient. The optimized medium composition was found to be 3.24% wheat straw (steam pretreated, particle size approx. 0.25 mm), 1.32% pharmamedia and 0.49% KHEPO 4. Other compounds such as inorganic nitrogen, MgSO4, CaCI2, trace elements and vitamins showed no marked positive effect on the enzyme yield by the fungus, while Tween-80 exhibited slight enhancing effect. The optimized culture medium and conditions gave 5347.4 nkat ml-1 of xylanase, 3.0 nkat ml-1 of/3-xylosidase, 1.0 nkat ml-1 of acetyl esterase, 89.7 nkat ml-1 of acetyl xylan esterase and 3.5 nkat ml-~ of t~-arabinosidase activities. In addition to xylanase activities, the culture filtrates exhibited cellulases (filter paper cellulase, carboxymethyl cellulase and /3-glucosidase), mannanases (endo-mannanase, fl-mannosidase and a-galactosidase) and other polysaccharases (pectinase, chitinase and a-amylase) activities. In a bioreactor culture, the production of xylanase and /3-xylosidase was markedly influenced by the pH and inoculum type. The fungus produced maximum enzymes when the pH was not controlled and repressed mycelial inoculum was used. Under these conditions the yield of xylanase was about 30% lower and that of/3-xylosisdase was at least 2-fold higher in comparison to those achieved in shake-flask cultures. The pH optimum of xylanase and /3-xylosidase was 5.0. The optimum temperature for xylanase was 80°C, while /3-xylosidase functioned optimally at 75°C. The enzymes exhibited remarkable stabilities at high temperatures (50-70°C) for prolonged period. At 70°C, the half-lives of xylanase and/3-xylosidase were approx. 204 h and 113 h, respectively.
Screening and identification of a thermophilic and alkalophilic bacterium producing xylanase
This study focuses on screening and identification of bacteria, which can produce alkaline xylanase at alkaline pH and high temperature. Bacterial isolates from corncob decaying soil, capable of hydrolyzing xylan were screened. Selected and purified 108 bacterial colonies grown on xylan-nutrient agar slants were activated and transferred into the fermentation medium. Six highest xylanase producing isolates were selected for further studies. Isolates CS 1 [132.0(±0.09)]The optimum pH value for the xylanase from isolate CS 1 and CS 88 was 8.4 and that of isolate CS 27 was 8.0. Based on the kinetic properties of xylanase, isolates CS 1 and CS 88 were selected and characterized and found to be belonging to genus Bacillus. As Bacillus CS 1 produced highest xylanase activities, 16S rDNA was analyzed and identified as Bacillus pumilus and selected for further studies to produce xylanase at 45 o C and pH 8.5. Vasanthy Arasaratnam et al Adv. Appl. Sci. Res., 2012, 3(1):242-250 _____________________________________________________________________________ 243 Pelagia Research Library
Enzyme and Microbial Technology, 2004
Xylanase was produced by growing Thermomyces lanuginosus DSM 10635 in different carbohydrate containing media. The xylanase was purified to electrophoretic homogeneity and some of its enzymatic properties were studied. The molecular mass of this xylanase estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was 25.5 kDa, and the pI was approximately 3.7. Applying mass spectrometric analysis, the average molecular mass of the xylanase was determined to be 21295.17 Da, which is practically the same as the theoretical molecular mass of the T. lanuginosus DSM 5826 xylanase (crystal structure 1yna). Accordingly, the thermostability and enzymatic properties of DSM 10635 xylanase were similar to DSM 5826 xylanase. The inactivation of DSM 10635 xylanase during the elevation of temperature proceeded slowly at pH 6.5 and 8.0, whereas at pH 5.0, the inactivation profile was steep, indicating that changes in the electrostatic interactions decrease the stability at lower pH. The thermostabilizing effect of the substrate on DSM 10635 xylanase was studied and it was observed to be significant only under acidic conditions. The half-life in the presence of 1% birchwood xylan (w/v) was 7-fold, 4-fold and 1.5-fold higher than without the substrate at pH 4.0, 5.0 and 6.5, respectively. No increase in the stability by the presence of substrate was observed at pH 9.0.
Thermal stability of β-xylanases produced by different Thermomyces lanuginosus strains
Enzyme and Microbial Technology, 2000
The thermostability of -xylanases produced by nine thermophilic Thermomyces lanuginosus strains in a coarse corn cob medium was assessed. The xylanase produced by T. lanuginosus strain SSBP retained 100% of its activity after 6 h at temperatures up to 65°C. In comparison seven ATCC strains and the DSM 5826 strain of T. lanuginosus only retained 100% xylanase activity at temperatures up to 60°C. Culture filtrates of T. lanuginosus strain SSBP grown on coarse corn cobs, oatspelts xylan, birchwood xylan, wheatbran, locust beangum, and sugar cane bagasse, retained 100% xylanase activity at temperatures up to 60°C. The xylanase produced on corn cobs was the most thermostable and showed an increase of approximately 6% from 70°C to 80°C. The T 1/2 of all strains at 70°C at pH 6.5 varied greatly from 63 min for strain ATCC 28083 to 340 min for strain SSBP. The xylanase of strain SSBP was much less thermostable at pH 5.0 and pH 12.0 with T 1/2 values of 11.5 min and 15 min, respectively at 70°C. At 50°C, the enzyme of T. lanuginosus strain SSBP produced on coarse corn cobs was stable within the pH range of 5.5-10.0. Furthermore, the enzyme retained total activity at 60°C for over 14 days and at 65°C for over 48 h. The xylanase of T. lanuginosus strain SSBP possesses thermo-and pH stability properties that may be attractive to industrial application.
Brazilian Journal of Microbiology, 2005
The use of waste as raw material is important for government economy and natural balance. The purpose of this work was to study the production of CMCase and xylanase by a Brazilian strain of Thermoascus aurantiacus in solid state fermentation (SSF) using different agricultural residues (wheat bran, sugarcane bagasse, orange bagasse, corncob, green grass, dried grass, sawdust and corn straw) as substrates without enrichment of the medium and characterize the crude enzymes. The study of the extracellular cellulolytic and hemicellulolytic enzymes showed that T. arantiacus is more xylanolytic than cellulolytic. The highest levels of enzymes were produced in corncob, grasses and corn straw. All the enzymes were stable at room temperature by 24 h over a broad pH range (3.0-9.0) and also were stable at 60ºC for 1 h. The optimum pH and temperature for xylanase and CMCase were 5.0-5.5 and 5.0 and 75ºC, respectively. The microorganism grew quickly in stationary, simple and low cost medium. The secreted extracellular enzymes presented properties that match with those frequently required in industrial environment.
Production and properties of the cellulase-free xylanase from Thermomyces lanuginosus IOC-4145
Brazilian Journal of Microbiology, 2002
In recent years, xylanases have expanded their use in many processing industries, such as pulp and paper, food and textile. Thermomyces lanuginosus IOC-4145 was able to produce a very high level of cellulase-free xylanase in shaken cultures using corncob as substrate (500 U/mL). An optimization of the medium composition in submerged fermentation was carried out aiming at a low cost medium composition for enzyme production. Statistical experiment design was employed for this purpose, pointing out corncob as the most important parameter, which affects enzyme production. Additionally, the influence of several chemicals on xylanase activity was investigated in the crude extract. A slight stimulation of the enzyme (5-15%) was achieved with NaCl and urea, both at 3 and 5 mM of concentration. On the other hand, dithiothreitol and β-mercaptoethanol at a molarity of 5mM have caused a strong stimulation of the enzyme (40-53%). The crude xylanase displayed appreciable thermostability, retaining almost 50% of activity during 24 hours of incubation at 50ºC; about 50% of activity was present at 60ºC even after 4 hours of incubation. The enzyme also exhibited good storage stability at-20ºC without any stabilizing agent.
Jurnal Akta Kimia Indonesia (Indonesia Chimica Acta), 2019
Xylanases is an extracellular enzyme that has prospects as enzymes that hydrolyze hemicellulose (xylan). In this study, carried out isolatied of bacteria from the hot springs Makula', Tana Toraja and determine the optimum conditions in producing the xylanase enzyme. The steps being taken are the rejuvenation of bacteria, the manufacture medium inoculum and the production medium, the measurement OD (Optical Density) measurements of protein and testing activities xylanase. The results obtained showed that the production time for B. stearothermophilus SL3A is in the 48 hours with a value of 0.1237 activity mU/mL and B. stearothermophilus SL3S at the 60 hours with a value of 0.1593 activity mU/mL. B. stearothermophilus SL3A have a protein content of 9.828 mg/mL and for B. stearothermophilus SL3S have a protein content of 10.07 mg/mL. Characteristics bacterial xylanase from B. stearothermophilus SL3A and B. stearothermophilus SL3S work optimally at pH 7 a temperature of 45 ºC. Crude ...
Co-Production of Cellulase and Xylanase Enzymes By Thermophilic Bacillus subtilis 276NS
International Journal of Biotechnology for Wellness Industries
Co-production of thermostable extracellular cellulase and xylanase was investigated using bacterial soil isolate. To evaluate the effect of culture conditions on the c-oproduction of both enzymes by Bacillus subtilis 276NS (GenBank accession number JF801740), a Plackett-Burman fractional factorial design was applied. Among the tested variables, yeast extract, sucrose and incubation time were the most significant variables increased cellulase and xylanase productions. Both of xylan and CMC (Carboxymethyl Cellulose) induced the xylanse enzyme production. A near-optimum medium formulation was obtained which increased the cellulase and xylanase enzymes 5.7-and 1.08fold higher than the yield obtained with the basal medium, respectively. Thereafter, the response surface methodology was adopted to acquire the best process conditions among the selected variables (xylan, CMC and Yeast Extract (YE)) required for improving xylanase yield. The optimal combinations of the major medium constituents for xylanase production evaluated using non-linear optimization algorithm of EXCEL-solver, was as follows (g/L): D-sucrose, 10; xylan, 10.367, CMC, 10.535; (NH4)2 SO4, 1.0; YE, 1.71; Tween-80, 0.4 and FeSO4, 0.25 mg/L, at pH 8.0, temperature 35 C and incubation time 24h under shaking. The predicted optimum thermostable xylanase activity was 360 U/ml, which was around 4-times the activity with the basal medium.