Study Of Cellulose Research Articles

Genome-wide characterization and expression analysis of MYB transcription factors in Chrysanthemum nankingense

BackgroundChrysanthemum is a popular ornamental plant worldwide. MYB (v-myb avian myeloblastosis viral oncogene homolog) transcription factors play an important role in everything from stress resistance to plant growth and development. However, the MYB family of chrysanthemums has not been the subject of a detailed bioinformatics and expression investigation.ResultsIn this study, we examined 324 CnMYB transcription factors from Chrysanthemum nankingense genome data, which contained 122 Cn1R-MYB, 183 CnR2R3-MYB, 12 Cn3R-MYB, 2 Cn4R-MYB, and 5 atypical CnMYB. The protein motifs and classification of CnMYB transcription factors were analyzed. Among them, motifs 1, 2, 3, and 4 were found to encode the MYB DNA-binding domain in R2R3-MYB proteins, while in other-MYB proteins, the motifs 1, 2, 3, 4, 5, 6, 7, and 8 encode the MYB DNA-binding domain. Among all CnMYBs, 44 genes were selected due to the presence of CpG islands, while methylation is detected in three genes, including CnMYB9, CnMYB152, and CnMYB219. We analyzed the expression levels of each CnMYB gene in ray floret, disc floret, flower bud, leaf, stem, and root tissues. Based on phylogenetic analysis and gene expression analysis, three genes appeared likely to control cellulose and lignin synthesis in stem tissue, and 16 genes appeared likely to regulate flowering time, anther, pollen development, and flower color. Fifty-one candidate genes that may be involved in stress response were identified through phylogenetic, stress-responseve motif of promoter, and qRT-PCR analyses. According to genes expression levels under stress conditions, six CnMYB genes (CnMYB9, CnMYB172, CnMYB186, CnMYB199, CnMYB219, and CnMYB152) were identified as key stress-responsive genes.ConclusionsThis research provides useful information for further functional analysis of the CnMYB gene family in chrysanthemums, as well as offers candidate genes for further study of cellulose and lignin synthesis, flowering traits, salt and drought stress mechanism.

Bridging Mathematics and Cellulose Studies: Investigating Closed Subspaces Hilbert Base Construction

This research focuses on mathematically analyzing specific aspects of cellulose, particularly its molecular sequences. The goal is to employ Hilbert base construction to quantify and understand the structural and mechanical characteristics of cellulose at the molecular level. This is crucial for advancing our knowledge in plant biology and engineering cellulose-based materials. The study rigorously investigates mathematical properties, such as the equivalence between complete subspaces and closed subspaces, the interplay between closed subspaces and their orthogonal complements, and the existence of the closest vector within the Hilbert space to closed subspaces. The outcomes of this research can be adapted and extended to contribute to the construction and manipulation of Hilbert bases specifically for understanding and characterizing the polymer sequences in cellulose. Moreover, the application of these mathematical concepts extends to both structural and functional analysis of cellulose, encompassing mechanical behavior, chemical interactions, and functional attributes. This rigorous mathematical approach offers a more nuanced understanding of cellulose beyond its physical structure, paving the way for groundbreaking advancements in cellulose research and applications.

Study of Cellulose and Starch-Based Biodegradable Foam Production Technology as Enviromentally Packaging Materials

Biodegradable foam is an alternative to styrofoam packaging which is not environmental friendly and harmful to health. Various sources of starch are widely available in nature which can be used as raw material for making biodegradable foam. Several researchers found that many types of starch can be used as the main material for making biodegradable foam, including cassava starch, corn starch, sago starch, durian seed starch, jackfruit seed starch, avocado seed starch, and banana weevil starch. The production methods used from several studies that have been carried out are thermopressing, baking process, microwave assisted molding, and extrusion. Biodegradable foam based on starch is brittle, sensitive to water and requires additional treatment to increase strength, flexibility and resistance to water so that it can be used commercially. The purpose of this article is to provide information on the production of biodegradable foam from various types of starch and cellulose. Based on the results of the analysis, the characteristics of biodegradable foam using the baking process method and modified sago starch resulted in better water absorption values compared to other types of starch and production methods.

Studies of Cellulose and Starch Utilization and the Regulatory Mechanisms of Related Enzymes in Fungi

Polysaccharides are biopolymers made up of a large number of monosaccharides joined together by glycosidic bonds. Polysaccharides are widely distributed in nature: Some, such as peptidoglycan and cellulose, are the components that make up the cell walls of bacteria and plants, and some, such as starch and glycogen, are used as carbohydrate storage in plants and animals. Fungi exist in a variety of natural environments and can exploit a wide range of carbon sources. They play a crucial role in the global carbon cycle because of their ability to break down plant biomass, which is composed primarily of cell wall polysaccharides, including cellulose, hemicellulose, and pectin. Fungi produce a variety of enzymes that in combination degrade cell wall polysaccharides into different monosaccharides. Starch, the main component of grain, is also a polysaccharide that can be broken down into monosaccharides by fungi. These monosaccharides can be used for energy or as precursors for the biosynthesis of biomolecules through a series of enzymatic reactions. Industrial fermentation by microbes has been widely used to produce traditional foods, beverages, and biofuels from starch and to a lesser extent plant biomass. This review focuses on the degradation and utilization of plant homopolysaccharides, cellulose and starch; summarizes the activities of the enzymes involved and the regulation of the induction of the enzymes in well-studied filamentous fungi.

INFRARED AND RAMAN SPECTROSCOPY IN PAPER AND PULP ANALYSIS

Infrared and Raman spectroscopy are essential analytical tools for the structural analysis of paper and pulp chemistry. The studies of cellulose, hemicellulose, lignin, thermal- and photo-induced oxidation; cross-linking; and various chemical treatments of pulp and paper products are all made possible using these forms of molecular spectroscopy. In this review, containing 70 references, a broad range of applications into pulp and paper materials, components, and processes is described from recent and classic research over predominantly the past 20 years.

Miscibility study of cellulose acetate/carboxylated poly(vinyl chloride) blend in cyclohexanone by viscosity, ultrasonic velocity, refractive index, and polarizing microscopic methods

The viscosity, ultrasonic velocity, refractive index, and density of cellulose acetate/carboxylated poly(vinyl chloride) (CA/C-PVC) blends in cyclohexanone, a common solvent, were measured at 30°C. After casting films of the blend for a 50:50 composition, polarizing micrographs were taken. Using the viscosity data, the interaction parameters were computed by employing two different equations. These values indicated that the CA/C-PVC blend is miscible. This was confirmed by ultrasonic, refractive index, density, and polarizing microscopic methods. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 557–561, 2001

Improved Cellulose Formation by anAcetobacter xylinum Mutant Limited in (Keto)Gluconate Synthesis

A mutation and enrichment strategy is described that allows the iso-lation of Acetobacter xylinum mutant strains which are restricted in (keto)gluconate synthesis and produce cellulose more efficiently, even under oxidative conditions. Acetobacter xylinum mutant strains obtained in this way may be very useful in the study of cellulose (over)synthesis and (keto)gluconate metabolism in Acetobacter xylinum, as well as in the improvement of bacterial cellulose fermentation processes.

Derivative infrared spectroscopy of cotton cellulose

AbstractA new technique of derivative infrared spectroscopy for the study of polymer structure with special reference to cotton cellulose is described. Absorption spectra of cotton cellulose are compared with second deravative spectra. In case of absorption spectra, while determining the wavelength and intensity of a given absorption, in many cases, difficulties arise due to the presence of an interfering band which, as a consequence of overlap, prevents the determination of the above properties. Derivative spectroscopy provides valuable information on structural properties of cellulose. It yields spectra gradient, which facilitates the separation of overlapping absorption bands to resolve and detect absorptions; neither were unresolvable as a consequence either of multiple bands overlap or of low intensity. Hence, the measured wavelength in the second derivative spectra are more precise than the absorption spectra. For fine structural studies of cellulose, derivative spectra may provide more useful information as the absorption bands are more clearly defined.

IR spectroscopic study of cellulose treated by guanidine and urea salt solutions

IR spectroscopic study of cellulose treated by guanidine and urea salt solutions

Solid-state 13C-N.M.R. and electron microscopy study on the reversible cellulose I→cellulose III I transformation in Valonia

An electron microscopy and a high-resolution 13C-n.m.r. study of cellulose is described and a previously unreported solid-state 13C-n.m.r. spectrum of cellulose III is presented. It is shown that a cyclic transformation of highly crystalline cellulose I ( Valonia) into cellulose III and back to cellulose I results in a material whose crystallites have a reduced lateral dimension similar to that in cotton and whose electron-diffraction patterns and 13C-n.m.r. spectra are very close to that of cotton. In addition, some new features in the 13C-n.m.r. spectrum of Valonia cellulose are reported.

Positron annihilation and X‐ray diffraction studies of cellulose and some derivatives

AbstractPositron lifetime measurements are reported over a temperature range from 290 to 380K on cellulose and certain of its derivatives. The lifetime spectra were resolved into three components each attributed to a different mode of positron annihilation in the polymer. The longest lifetime component is associated with the decay of ortho‐positronium and is a function of the average cavity distribution in the sample. It is observed that significant differences exist in the lifetimes of positrons in cellulose and its derivatives which can be interpreted as evidence for changes in the free volume distribution in these materials. Comparison of positron decay in samples of cellulose acetate prepared at both room temperature and elevated temperature indicate that the phenomena of gelation in this material is accompanied by a reduction of free volume. The correlation of such observations with the dynamic properties of these polymers is discussed.

Deuteration of cotton fibers. II. A novel method of deuteration-infrared study of cellulose in fiber form

A new technique enabling the use of cellulosic material in the fiber form during deuteration-infrared studies is reported. A minipress, modified to suit the new technique, is described. Since the material was studied in the fiber form, danger of fiber modification during film formation was avoided. Although the usual KBr pellet technique was utilized for scanning the spectra of the deuterated fibers, preparation of pellet as well as scanning were carried out under fully dry conditions, thus completely avoiding the rehydrogenation of deuterated fibers. The modified minipress containing the pellet forms an airtight assembly allowing repeat scans after any length of time without affecting the quality of the spectra of the deuterated sample.

Electron-microscope study of cellulose and Capron fibers with different strenghts

Oriented polymer fibers whose strengths differ by a factor of two have been subjected to an electron-microscope study. Both cellulose (σ=40 and 75 kgf/mm2) and Capron (σ=80 and 170 kgf/mm2) fiber were investigated. Specimens were obtained by ultrasonic dispersion followed by negative contrasting of the dispersion products with FVK solution. It is shown that there is no correlation between the transverse dimensions of the microfibrils and the strength of the investigated fibers.

Viscometric Studies of Cellulose in Cotton in Relation to Mechanical Processing

A study was undertaken at the Southern Regional Research Laboratory to determine whether or not the mechanical processing of cotton fibers into yarn causes any chemical degradation to the cellulose. The study seemed timely in view of a report [22] indicating that the mechanical processing of cotton into yarn by conventional textile machinery causes as much as 30% average reduction in intrinsic viscosity. Studies were made on four sets of samples which had been treated as follows: ( 1) powdered in a Wiley mill; (2) processed a number of times through a new type of textile cotton opener developed at the Southern Regional Research Laboratory; (3) mechanically processed in essen tially the same manner as in the study referred to above; and (4) portions of the same samples used by Krieble and Whitwell [22]. The viscosity measurements determined by the methods employed at the Southern Regional Research Laboratory failed to show any demonstrable chemical damage to the cellulose which could be associated with processing. When the new method described by Krieble and Whitwell was applied to the viscosity data, the linear plots depended upon for extrapolation could not be obtained. It was concluded that the damage previously reported to have been found is not fully supported by a statistical treatment of the data; also, that chemical damage is not produced in ordinary cotton textile processing to any appreciable extent, although it might conceivably become notice able in excessively processed cotton. Some suggestions are given to explain the failure to secure linear plots by the suggested new method.

Cellulose Studies. Part XVI. The Reaction of Cellulose with Formaldehyde

A new method for reacting cellulose and formaldehyde in the vapor phase using acid catalysts is described. Acids as weak as boric acid were effective in introducing up to 6% covalently bonded formaldehyde. The results of reaction conditions where catalyst concentration ranged from 1%-10% and reaction temperature ranged from 110°-150°C are presented. A chemical investigation of the structure of the product of the reaction showed that formalde- , hyde preferentially substitutes the secondary hydroxyl groups of cellulose to yield a 'structure represented by the general formula R-O-CH2-O-R', where R and R' indicate glucose residues in parallel chains.

Molecular Weight of Native Cellulose

THE molecular weight of cellulose is of great interest to cellulose chemistry, and many attempts have been made to determine it. The cellulose derivatives, esters and ethers, can in general be dissolved in simple organic solvents, and their molecular weights determined by the osmotic pressure method. It is questionable, however, if the derivatives can be prepared without degradation of the cellulose molecule. Therefore the study of cellulose in cuprammonium solutions is of very great interest. It has never been possible to carry out osmotic measurements of these solutions, owing to their high vapour pressure and the difficulties of membrane materials. Staudinger1 has extrapolated his ‘viscosity rule’ from measurements of relatively low molecular weight materials and obtained degrees of polymerization of 2,000–3,000 for native cotton and ramie. Sedimentation equilibrium measurements were performed by Kraemer2, who obtained values up to 1,300 for purified cotton linters, and estimated the molecular weight of native cellulose to be at least 570,000 (D.P. 3,500). Later, Mosimann3 showed that sedimentation equilibrium experiments with filament molecules (nitrocelluloses) of very high molecular weights give doubtful results owing to swelling-pressure effects.