Microbial Retting of Banana Pseudostem

Fibrous wastes correspond to approximately 54.3 wt.-% of a banana plant. The waste weight is mainly of bunches, stems, and leaves. These ligno-cellulosic fibre waste can be designed and tailored to yield value added products which can be exploited by the farmers, exporters and weavers. Pectin (plant cement) and hemicelluloses (22-25%) found in plant cell walls in the plate (middle lamella). These macromolecules have needs to be hydrolyzed faster without affecting the quality of fibre. The chemical and mechanical processes adopted for fibres actually affect color uptake, strength of fibre thus fetching lower price. We report a biological ecofriendly method of retting where pectinases produced by the endophytic microorganisms of banana pseudostem were used to separate the fibre bundles of cellulose.. Endophytes are microorganisms which live in close relationship with living plant tissues in a cooperative relationship delivering a few auxiliary metabolites and proteins with the possibility to hydrolyse a few plant-determined macromolecules of the host. They spend the entire or part of their lifecycle colonizing within sound tissues of the host plants.The endophytic pectinase helps to break down the cell walls and can find commercial application in extraction of fibres.Seven bacterial isolates were screened and isolated in pectinase screening agar medium [PSAM]. Pectinase producing endophytic bacteria is isolated from corm of Amorphophallus paeoniifolius reported by us are Staphylococcus sciuri, Exiguobacterium acetylicum, Exiguobacterium indicum which are good pectinase producers having specific activity of 8.26, 12.61, 6.81 respectively. Treatment of banana pseudostem with these microbes showed 91%, 94%, 96.7% loss in the total weight of stem leaving behind pure cellulose fibres.

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Silicification of wood-cell walls

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100169870 ◽

1994 ◽

Vol 52 ◽

pp. 428-429

Author(s):

S. E. Keckler ◽

D. M. Dabbs ◽

N. Yao ◽

I. A. Aksay

Keyword(s):

Electron Microscopy ◽

Cell Wall ◽

Cell Walls ◽

Lignin Content ◽

Resin Composite ◽

Middle Lamella ◽

Cellulose Fibers ◽

Complex Structures ◽

Rich Region ◽

Inorganic Precursors

Cellular organic structures such as wood can be used as scaffolds for the synthesis of complex structures of organic/ceramic nanocomposites. The wood cell is a fiber-reinforced resin composite of cellulose fibers in a lignin matrix. A single cell wall, containing several layers of different fiber orientations and lignin content, is separated from its neighboring wall by the middle lamella, a lignin-rich region. In order to achieve total mineralization, deposition on and in the cell wall must be achieved. Geological fossilization of wood occurs as permineralization (filling the void spaces with mineral) and petrifaction (mineralizing the cell wall as the organic component decays) through infiltration of wood with inorganics after growth. Conversely, living plants can incorporate inorganics into their cells and in some cases into the cell walls during growth. In a recent study, we mimicked geological fossilization by infiltrating inorganic precursors into wood cells in order to enhance the properties of wood. In the current work, we use electron microscopy to examine the structure of silica formed in the cell walls after infiltration of tetraethoxysilane (TEOS).

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The Impact of Filler Geometry on Polylactic Acid-Based Sustainable Polymer Composites

Molecules ◽

10.3390/molecules26010149 ◽

2020 ◽

Vol 26 (1) ◽

pp. 149

Author(s):

Karol Leluk ◽

Stanisław Frąckowiak ◽

Joanna Ludwiczak ◽

Tomasz Rydzkowski ◽

Vijay Kumar Thakur

Keyword(s):

Polymer Composites ◽

Polylactic Acid ◽

Matrix Material ◽

Chemical Properties ◽

Precipitated Calcium Carbonate ◽

Cellulose Fibres ◽

Shape Factors ◽

Pure Cellulose ◽

Physico Chemical ◽

The Impact

Recently, biocomposites have emerged as materials of great interest to the scientists and industry around the globe. Among various polymers, polylactic acid (PLA) is a popular matrix material with high potential for advanced applications. Various particulate materials and nanoparticles have been used as the filler in PLA based matrix. One of the extensively studied filler is cellulose. However, cellulose fibres, due to their hydrophilic nature, are difficult to blend with a hydrophobic polymer matrix. This leads to agglomeration and creates voids, reducing the mechanical strength of the resulting composite. Moreover, the role of the various forms of pure cellulose and its particle shape factors has not been analyzed in most of the current literature. Therefore, in this work, materials of various shapes and shape factors were selected as fillers for the production of polymer composites using Polylactic acid as a matrix to fill this knowledge gap. In particular, pure cellulose fibres (three types with different elongation coefficient) and two mineral nanocomponents: precipitated calcium carbonate and montmorillonite were used. The composites were prepared by a melt blending process using two different levels of fillers: 5% and 30%. Then, the analysis of their thermomechanical and physico-chemical properties was carried out. The obtained results were presented graphically and discussed in terms of their shape and degree of filling.

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Enhancing the thermostability and activity of uronate dehydrogenase from Agrobacterium tumefaciens LBA4404 by semi-rational engineering

Bioresources and Bioprocessing ◽

10.1186/s40643-019-0267-3 ◽

2019 ◽

Vol 6 (1) ◽

Cited By ~ 1

Author(s):

Hui-Hui Su ◽

Fei Peng ◽

Pei Xu ◽

Xiao-Ling Wu ◽

Min-Hua Zong ◽

...

Keyword(s):

Agrobacterium Tumefaciens ◽

Rational Design ◽

Glucuronic Acid ◽

Specific Activity ◽

Value Added ◽

Catalytic Efficiency ◽

Site Directed Mutagenesis ◽

Glucaric Acid ◽

Triple Mutant ◽

Pharmaceutical Industries

Abstract Background Glucaric acid, one of the aldaric acids, has been declared a “top value-added chemical from biomass”, and is especially important in the food and pharmaceutical industries. Biocatalytic production of glucaric acid from glucuronic acid is more environmentally friendly, efficient and economical than chemical synthesis. Uronate dehydrogenases (UDHs) are the key enzymes for the preparation of glucaric acid in this way, but the poor thermostability and low activity of UDH limit its industrial application. Therefore, improving the thermostability and activity of UDH, for example by semi-rational design, is a major research goal. Results In the present work, three UDHs were obtained from different Agrobacterium tumefaciens strains. The three UDHs have an approximate molecular weight of 32 kDa and all contain typically conserved UDH motifs. All three UDHs showed optimal activity within a pH range of 6.0–8.5 and at a temperature of 30 °C, but the UDH from A. tumefaciens (At) LBA4404 had a better catalytic efficiency than the other two UDHs (800 vs 600 and 530 s−1 mM−1). To further boost the catalytic performance of the UDH from AtLBA4404, site-directed mutagenesis based on semi-rational design was carried out. An A39P/H99Y/H234K triple mutant showed a 400-fold improvement in half-life at 59 °C, a 5 °C improvement in $$ {\text{T}}_{ 5 0}^{ 1 0} $$ T 50 10 value and a 2.5-fold improvement in specific activity at 30 °C compared to wild-type UDH. Conclusions In this study, we successfully obtained a triple mutant (A39P/H99Y/H234K) with simultaneously enhanced activity and thermostability, which provides a novel alternative for the industrial production of glucaric acid from glucuronic acid.

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UV-microscopic analysis of acetylated spruce and birch cell walls

Holzforschung ◽

10.1515/hf.2004.073 ◽

2004 ◽

Vol 58 (5) ◽

pp. 483-488 ◽

Cited By ~ 7

Author(s):

Christian Hansmann ◽

Manfred Schwanninger ◽

Barbara Stefke ◽

Barbara Hinterstoisser ◽

Wolfgang Gindl

Keyword(s):

Cell Walls ◽

Middle Lamella ◽

Microscopic Analysis ◽

Weight Percent ◽

Cellular Level ◽

Uv Spectrum ◽

Spectral Shifts ◽

Microscopy Analysis ◽

Absorbance Peak ◽

Absorbance Spectra

Abstract Spruce and birch earlywood was acetylated to different weight percent gains using three different acetylation procedures. The absorbance spectra of secondary cell wall and compound cell corner middle lamella were determined by means of UV microscopy. Analysis of the spectra showed that the characteristic lignin absorbance peak in the UV spectrum of wood around 280 nm shifted to shorter wavelengths in acetylated samples. A distinct relationship between achieved weight percent gains after acetylation and observed spectral shifts could be established revealing a certain potential to measure acetylation on a cellular level by means of UV microscopy.

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Maximizing Anhydrosugar Production from Fast Pyrolysis of Eucalyptus Using Sulfuric Acid as an Ash Catalyst Inhibitor

Catalysts ◽

10.3390/catal8120609 ◽

2018 ◽

Vol 8 (12) ◽

pp. 609 ◽

Cited By ~ 3

Author(s):

Dongyan Zhang ◽

Yuyang Fan ◽

Anqing Zheng ◽

Zengli Zhao ◽

Fengyun Wang ◽

...

Keyword(s):

Rank Order ◽

Maximum Yield ◽

Fast Pyrolysis ◽

Value Added ◽

Gas Chromatography Mass Spectrometry ◽

Cellulose Content ◽

Pyrolysis Gas ◽

X Ray ◽

Theoretical Yield ◽

Pure Cellulose

Anhydrosugars, such as levoglucosan (LG), are high value-added chemicals which are mainly derived from fast pyrolysis of pure cellulose. However, fast pyrolysis of raw lignocellulosic biomass usually produces a very low amount of levoglucosan, since alkali and alkaline earth metals (AAEM) present in the ash can serve as the catalysts to inhibit the formation of levoglucosan through accelerating the pyranose ring-opening reactions. In this study, eucalyptus was impregnated with H2SO4 solutions with varying concentrations (0.25–1.25%). The characteristics of ash derived from raw and H2SO4-impregnated eucalyptus were characterized by X-ray fluorescence spectroscopy (XRF) and X-ray diffraction (XRD). The pyrolysis behaviors of raw and H2SO4-impregnated eucalyptus were performed on the thermogravimetric analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). TG analysis demonstrated that the H2SO4-impregnated eucalyptus produced less char than raw eucalyptus. Py-GC/MS analysis showed that even small amounts of H2SO4 can obviously improve the production of anhydrosugars and phenols and suppressed the formation of carboxylic acids, aldehydes, and ketones from fast pyrolysis of eucalyptus. The rank order of levoglucosan yield from raw and impregnated eucalyptus was raw < 1.25% H2SO4 < 1% H2SO4 < 0.75% H2SO4 < 0.25% H2SO4 < 0.5% H2SO4. The maximum yield of levoglucosan (21.3%) was obtained by fast pyrolysis of eucalyptus impregnated with 0.5% H2SO4, which was close to its theoretical yield based on the cellulose content. The results could be ascribed to that H2SO4 can react with AAEM (e.g., Na, K, Ca, and Mg) and lignin to form lignosulfonate, thus acting as an inhibitor to suppress the catalytic effects of AAEM during fast pyrolysis of eucalyptus.

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The morphology of grain abscission in Zizania aquatica

Canadian Journal of Botany ◽

10.1139/b80-261 ◽

1980 ◽

Vol 58 (21) ◽

pp. 2269-2273 ◽

Cited By ~ 6

Author(s):

H. B. Hanten ◽

G. E. Ahlgren ◽

J. B. Carlson

Keyword(s):

Wild Rice ◽

Cell Walls ◽

Vascular Tissue ◽

Embryo Sac ◽

Middle Lamella ◽

Abscission Zone ◽

Rice Grains ◽

Zizania Aquatica ◽

Parenchyma Cells ◽

Anatomical Evidence

The anatomical development of the abscission zone in grains of Zizania aquatica L. was correlated with development of the embryo. The abscission zone is well developed when the embryo sac is mature. Soon after pollination, the first anatomical evidence of abscission appears as plasmolysis of the separation layer parenchyma cells. This is followed by separation of the layers by dissolution of the middle lamella and fragmentation of cell walls. Persistence of intact vascular tissue and presence of a surrounding cone-shaped mass of lignified cells may be involved in abscission of wild rice grains.

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Optimization of Metal Ions in Sugarcane Bagasse Fermenting Medium for the Production of Streptokinase by Streptococcus equisimilis

Science Letters ◽

10.47262/sl/9.2.132021003 ◽

2021 ◽

Vol 9 (2) ◽

pp. 24-30

Keyword(s):

Metal Ions ◽

Sugarcane Bagasse ◽

Specific Activity ◽

Gel Filtration ◽

Value Added ◽

Cost Effective ◽

Fermentation Medium ◽

Exchange Chromatography ◽

Sds Page ◽

The Cost

Streptokinase is a fibrinolytic enzyme and a product of β-hemolytic Streptococci strains. This enzyme is used as a medication to break down clots in some cases of heart disease. Streptococcus equisimilis, a species of group C Streptococci, is widely used for the production of streptokinase by fermentation technology. In this study, the sugarcane bagasse fermentation medium was optimized for metal ions (KH2PO4, MgSO4.7H2O, CaCO3 and NaHCO3) at various levels to attain the maximal production of streptokinase. Sugarcane bagasse was used due to its profuse availability and as an ideal substrate for microbial processes for the manufacturing of value-added products. The results showed that maximal streptokinase production was found at 0.04% KH2PO4, 0.04% MgSO4.7H2O, 0.15% NaHCO3 and 0.04% CaCO3. Finally, the optimized medium resulted in 84.75 U/mg specific activity and 74.5% recovery. The purification process was carried out simultaneously using ammonium sulfate precipitation, ion-exchange chromatography, and gel filtration. Finally, a purified sample of streptokinase was run on SDS-PAGE and resolute 47 kDa molecular weight. The use of β-hemolytic Streptococci to obtain streptokinase is not free from health risks and is related to anaphylaxis. This study provides a way forward for the cost-effective ways to obtain streptokinase for the treatment of thrombosis.

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