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

1982 ◽  
Vol 28 (3) ◽  
pp. 275-280 ◽  
Author(s):  
A. M. DESCHAMPS ◽  
J. COMTAT ◽  
N. NOUVION ◽  
J. M. LEBEAULT
Keyword(s):  
Birch Wood ◽  
Birch Wood Xylan

Properties of plasticized composite films prepared from nanofibrillated cellulose and birch wood xylan

Cellulose ◽  
2012 ◽  
Vol 19 (6) ◽  
pp. 2015-2031 ◽  
Author(s):  
Natanya M. L. Hansen ◽  
Thomas O. J. Blomfeldt ◽  
Mikael S. Hedenqvist ◽  
David V. Plackett
Keyword(s):  
Composite Films ◽  
Nanofibrillated Cellulose ◽  
Birch Wood ◽  
Birch Wood Xylan

scholarly journals The Structure of an Aldopentaouronic Acid from a Birch Wood Xylan.

1962 ◽  
Vol 16 ◽  
pp. 1027-1030 ◽  
Author(s):  
Tore E. Timell ◽  
U. K. Virtanen ◽  
A. Salmenperä ◽  
A. Block-Bolten ◽  
J. M. Toguri ◽  
...  
Keyword(s):  
Birch Wood ◽  
Birch Wood Xylan

scholarly journals MATHEMATICAL OPTIMIZATION OF THE PROCESS OF BIRCH WOOD XYLAN SULFATION BY SULFAMIC ACID IN N, N-DIMETHYLFORMAMIDE MEDIUM

2021 ◽  
pp. 87-94
Author(s):  
Aleksandr Sergeyevich Kazachenko ◽  
Vladimir Aleksandrovich Levdansky ◽  
Aleksandr Vladimirovich Levdansky ◽  
Boris Nikolayevich Kuznetsov
Keyword(s):  
Nmr Spectroscopy ◽  
Mathematical Optimization ◽  
Sulfamic Acid ◽  
13C Nmr Spectroscopy ◽  
Sulphur Content ◽  
Effect Of Temperature ◽  
High Yield ◽  
Birch Wood ◽  
Optimal Conditions ◽  
Birch Wood Xylan

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.

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

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
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.

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

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

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

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.

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

2018 ◽  
Vol 10 (2) ◽  
pp. 142-151 ◽  
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

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

Catalysts ◽  
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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