Degradation of purified birch-wood xylan and production of xylanase by wood-decaying bacteria.

The effect of temperature and duration of sulfation of birch wood xylan by sulfamic acid in N, N-dimethylformamide (DMF) medium in the presence of urea on the yield of sulfated xylan and on the sulphur content was studied. By mathematical optimization, the sulfation conditions have been established allowing to achieve a high yield of the obtained xylan sulfates with a high sulphur content. Under optimal sulfation conditions: temperature 100±3 °C, duration 1.5 hours, the yield of sulfated xylan reaches to 63% mas. and the content of sulfur – 17.6% mas. The presence of sulfate groups in sulfated xylan samples obtained under optimal conditions was confirmed by elemental analysis and FTIR and 13C NMR spectroscopy.

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Isolation, Production, and Characterization of Thermotolerant Xylanase from Solvent TolerantBacillus vallismortisRSPP-15

International Journal of Polymer Science ◽

10.1155/2015/986324 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10 ◽

Cited By ~ 7

Author(s):

Rajeeva Gaur ◽

Soni Tiwari ◽

Priyanka Rai ◽

Versha Srivastava

Keyword(s):

Organic Solvent ◽

Xylanase Activity ◽

Industrial Applications ◽

Birch Wood ◽

Bacterial Strains ◽

Xylanase Production ◽

Birch Wood Xylan ◽

Bacillus Vallismortis ◽

Cu Ions

Sixty bacterial strains isolated from the soils sample in the presence of organic solvent were screened for xylanase production. Among them, strain RSPP-15 showed the highest xylanase activity which was identified asBacillus vallismortis. The isolate showed maximum xylanase production (3768 U/mL) in the presence of birch wood xylan and beef extract at 55°C pH 7.0 within 48 h of incubation. The enzyme activity and stability were increased 181.5, 153.7, 147.2, 133.6, and 127.9% and 138.2, 119.3, 113.9, 109, and 104.5% in the presence of Co2+, Ca2+, Mg+2, Zn+2, and Fe+3ions (10 mM). Xylanase activity and stability were strongly inhibited in the presence of Hg and Cu ions. The enzyme was also stable in the presence of 30% ofn-dodecane, isooctane,n-decane, xylene, toluene,n-hexane,n-butanol, and cyclohexane, respectively. The presence of benzene, methanol, and ethanol marginally reduced the xylanase stability, respectively. This isolate may be useful in several industrial applications owing to its thermotolerant and organic solvent resistance characteristics.

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Synthesis and characterization of birch wood xylan succinoylated in 1-n-butyl-3-methylimidazolium chloride

Polymer Chemistry ◽

10.1039/c1py00086a ◽

2011 ◽

Vol 2 (9) ◽

pp. 2010 ◽

Cited By ~ 23

Author(s):

Natanya M. L. Hansen ◽

David Plackett

Keyword(s):

Synthesis And Characterization ◽

Birch Wood ◽

Birch Wood Xylan

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Sylfation of Birch Wood Xylan with Sulfamic Acid in 1,4-dioxane

Journal of Siberian Federal University Chemistry ◽

10.17516/1998-2836-0241 ◽

2021 ◽

Vol 14 (3) ◽

pp. 325-336

Author(s):

Vladimir A. Levdansky ◽

◽

Alexander A. Kondrasenko ◽

Alexander V. Levdansky ◽

Boris N. Kuznetsov

Keyword(s):

Nmr Spectroscopy ◽

Sulfur Content ◽

Sulfamic Acid ◽

Birch Wood ◽

Birch Wood Xylan ◽

First Time

Sulfation of birch wood xylan in 1,4-dioxane by sulfamic acid in the presence of urea at 90 and 100 °C was studied for the first time. The effect of the duration of xylan sulfation on the yield of xylan sulfates and the sulfur content in them was studied. It was found that the sulfur content in the obtained xylan sulfates increases from 12.5 to 17.5 wt% with an increase in the duration of sulfation from 2 to 4 hours. The structure of initial and sulfated xylan was studied by FTIR and NMR spectroscopy. The ease of purification of the obtained xylan sulfates from 1,4-dioxane in comparison with the purification of xylan sulfates obtained by sulfation in pyridine and N, N‑dimethylformamide is an advantage of the proposed method of xylan sulfation

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Purification and evaluation for effects of temperature on extracellular xylanase activity from Aspergillus oryzae DSM 1863

Journal of Vietnamese Environment ◽

10.13141/jve.vol8.no1.pp9-13 ◽

2017 ◽

Vol 8 (1) ◽

pp. 9-13

Author(s):

Thi Tuyen Do ◽

Sy Le Thanh Nguyen ◽

Thi Thao Nguyen

Keyword(s):

Aspergillus Oryzae ◽

Specific Activity ◽

Xylanase Activity ◽

Residual Activity ◽

Deae Cellulose ◽

Exchange Chromatography ◽

Birch Wood ◽

Sds Page ◽

Birch Wood Xylan ◽

Effects Of Temperature

Xylanase was purified from the crude culture of Aspergillus oryzae DSM1863 by sephadex G200 and DEAE – cellulose ion exchange chromatography. The molecular mass of the purified xylanase determined by SDS–PAGE was 21 kDa with a specific activity of 6768 U/mg towards 1% (w/v) of birch wood xylan. The optimum temperature was observed at 60°C. The enzyme was thermostable in the temperature range of 37-50°C with a high residual activity of 62-74% (650.6-775.9 U/mg protein). Enzyme xylanase được tinh sạch từ dịch lên men của chủng Aspergillus oryzae DSM1863 sau khi qua cột sắc ký lọc gel sephadex G200 và sắc ký trao đổi ion DEAE – cellulose. Khối lượng phân tử của enzyme xylanase tinh sạch được xác định bằng điên di đồ SDS- PAGE. Xylanase tinh sạch có kích thước là 21 kDa với hoạt tính đặc hiệu đạt 6768 U/mg sau khi được xác định với nồng độ cơ chất là 1% birch wood xylan. Nhiệt độ tối ưu để enzyme hoạt động mạnh nhất là 60C. Enzyme xylanase khá bền nhiệt. Hoạt tính của enzyme vẫn còn duy trì 62-74% (hoạt tính đặc hiệu đạt 650.6-775.9 U/mg protein) sau khi 8 giờ ủ ở 37-50°C.

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Thermal modification of birch wood to obtain desired color

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/316/1/012087 ◽

2019 ◽

Vol 316 ◽

pp. 012087

Author(s):

M Ermochenkov ◽

Y Batyrev

Keyword(s):

Thermal Modification ◽

Birch Wood

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Developing Ways of Obtaining Quality Hydrolyzates Based on Integrating Catalytic Peroxide Delignification and the Acid Hydrolysis of Birch Wood

Catalysis in Industry ◽

10.1134/s2070050418020113 ◽

2018 ◽

Vol 10 (2) ◽

pp. 142-151 ◽

Cited By ~ 1

Author(s):

B. N. Kuznetsov ◽

N. V. Chesnokov ◽

O. V. Yatsenkova ◽

I. G. Sudakova ◽

A. M. Skripnikov ◽

...

Keyword(s):

Acid Hydrolysis ◽

Birch Wood ◽

Hydrolysis Of ◽

Peroxide Delignification

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Fractionation of Birch Wood by Integrating Alkaline-Acid Treatments and Hydrogenation in Ethanol over a Bifunctional Ruthenium Catalyst

Catalysts ◽

10.3390/catal11111362 ◽

2021 ◽

Vol 11 (11) ◽

pp. 1362

Author(s):

Boris N. Kuznetsov ◽

Sergey V. Baryshnikov ◽

Angelina V. Miroshnikova ◽

Aleksandr S. Kazachenko ◽

Yuriy N. Malyar ◽

...

Keyword(s):

Microcrystalline Cellulose ◽

Catalytic Hydrogenation ◽

Liquid Product ◽

Gel Permeation Chromatography ◽

Ruthenium Catalyst ◽

Birch Wood ◽

Gaseous Products ◽

Liquid Products ◽

First Time

For the first time, the fractionation of birch wood into microcrystalline cellulose, xylose and methoxyphenols is suggested based on the integration of alkali-acid pretreatments and hydrogenation in ethanol over a bifunctional Ru/C catalyst. It is established that removal of hemicelluloses during pretreatments of birch wood influences the yields of the liquid, gaseous and solid products of the non-catalytic and catalytic hydrogenation of pretreated samples in ethanol at 225 °C. The bifunctional Ru/carbon catalyst affects in different ways the conversion and yields of products of hydrogenation of the initial and acid- and alkali-pretreated birch wood. The most noticeable influence is characteristic of the hydrogenation of the acid-pretreated wood, where in contrast to the non-catalytic hydrogenation, the wood conversion and the yields of liquid products increase but the yields of the solid and gaseous products decrease. GC-MS, gel permeation chromatography and elemental analysis were used for characterization of the liquid product composition. The molecular mass distribution of the liquid products of hydrogenation of the initial and pretreated wood shifts towards the low-molecular range in the presence of the catalyst. From the GC-MS data, the contents of monomer compounds, predominantly 4-propylsyringol and 4-propanolsyringol, increase in the presence of the ruthenium catalyst. The solid products of catalytic hydrogenation of the pretreated wood contain up to 95 wt% of cellulose with the structure, similar to that of microcrystalline cellulose.

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