Amorphous Regions Of Cellulose Research Articles

The effect of traditional processing craft on the hygroscopicity of palm leaf manuscripts

Palm leaf manuscripts, which are crucial carriers of historical, religious, scientific, and artistic information in East and Southeast Asia, specifically encapsulate significant aspects of Buddhist culture and thus require comprehensive research and preservation efforts. The base material of palm leaf manuscripts is processed palm leaves, which are hygroscopic and profoundly affected by environmental humidity. Currently, there is a research gap regarding the impact of traditional processing crafts and natural aging on the hygroscopicity of palm leaf manuscripts. Utilizing dynamic water vapor sorption (DVS), the hygroscopic properties of palm leaves from various years were assessed before and after traditional processing in Yunnan Province, China. The results show that traditional processing slightly increases the equilibrium moisture content (EMC) in environments with 0 to 60% relative humidity (RH), but significantly lowers EMC in high humidity environments, with reductions up to 19.01%. Additionally, hysteresis doubled post-processing, indicating enhanced stability under fluctuating humidity conditions. Sorption models suggest that traditional processing increases the number of adsorption sites while reducing physical adsorption or capillary condensation. FT-IR (Fourier-transform infrared spectroscopy) analysis indicates that the relative contents of cellulose and hemicellulose were reduced by 39.90% and 3.97%, respectively. Degradation occurring in both the crystalline and amorphous regions of cellulose. After natural aging, the hygroscopicity of processed palm leaves improved across the entire humidity range of 0 to 95%, and there was a slight increase in hysteresis. This is due to the increase in both adsorption sites and physical adsorption capabilities. FT-IR results also indicate that the relative contents of cellulose and hemicellulose were decreased by 57.52% and 19.83% after nature aging, respectively. These findings confirm that traditional processing improves the writability and humidity resilience of the leaves, while natural aging enhances their overall hygroscopic properties. This research contributes to our understanding of how humidity damages palm leaf manuscripts. aids in determining optimal RH ranges for storage, and assesses the effectiveness of consolidation treatments in their long–term preservation.

Cell Wall Modification Based on Combination Reagents to Improve Dimensional Stability of Wood with High Efficiency.

Although γ-methacryloxypropyltrimethoxysilane (MPS) was proved to be an effective reagent for improving the dimensional stability of wood, a bottleneck in ASE value (around 50%) existed. The reason was that MPS with low polarity opened few hydrogen bonds in the amorphous region of cellulose, while these hydrogen bonds could be reopened by water. Therefore, citric acid (CA) is chosen to cooperate with MPS to further enhance the dimensional stability of wood. In this paper, MPS and CA were used to modify wood individually (MW and CW) or with different combinations, that is, one-step modification (M/CW) and two-step modification with MPS first (M-CW) or CA first (C-MW). CA and MPS concentrations were optimized at 5 wt%. The ASE value for M/CW was only 25.74% at a weight percent gain (WPG) of 6.43%, which was only 0.6 times to MW or 0.7 times to CW. For M-CW, the ASE value gradually decreased with the soaking cycles, from 65.64% at a WPG of 9.05% to 51.20%. The C-MW had the best dimensional stability, with the ASE value 75.35% at a WPG of 11.50%. Although it decreased during the first soaking cycle, it stabilized at 62.20% at last. SEM and EDS images showed that the polymer mainly distributed in cell walls and few in cell lumen in C-MW. Thus, the enhanced dimensional stability of C-MW could be explained by CA opening the hydrogen bonds in the amorphous region of cellulose first, which provided more binding sites for MPS.

Effects of oil heat treatment on poplar wood properties: A pilot scale study

Pilot-scale oil heat treatment was conducted to enhance the quality of poplar wood obtained from a fast-growing plantation. Three target temperatures, namely 180, 190, and 200 ˚C, were chosen for the oil heat treatment process. Clear, small specimens were cut from the lumber, following the prescribed standards for assessing wood quality. Light microscopy revealed the ruptures and deformation of the wood cell wall as the treatment temperature increased. The volumetric swelling of the treated specimen decreased proportionally with the increase in treatment temperature. The impact of oil heat treatment on the mechanical properties of wood varied depending on the specific type of mechanical strength and processing temperature. The modulus of rupture, toughness, and hardness of the treated specimens drastically decreased at 200°C. However, the specimens treated at 200°C exhibited much lower mass loss during the fungal decay test. The results of the analytical test showed an increase in the crystalline cellulose content and thermal stability of the treated wood, due to the thermal degradation of hemicelluloses and amorphous regions of cellulose. Overall, it is concluded that oil heat treatment of poplar wood in the optimal temperature is an efficient approach to upgrade its quality with minimal reduction in mechanical strength.

Selective Microcrystalline Cellulose Extraction from Chinese Medicine Residues via Direct PMS Oxidation

The valorization of Chinese medicine residues (CMRs) into high-value-added products, such as microcrystalline cellulose (MCC), has garnered significant interest in the current post-pandemic era, particularly in regions where Chinese medicine (CM) is widely utilized (i.e., Southeast Asia). In this study, we propose a facile and economical protocol for selectively extracting MCC from CMRs via one-step direct peroxymonosulfate (PMS) oxidation without the need for intricate steps. Importantly, our proposed protocol has been verified to be versatile and can be applied to various solid waste sources rich in cellulose, with an average extraction rate of 75%. Analysis using the Fukui index revealed that the β-O-4 bond, the aromatic ring in lignin, specific O sites in hemicellulose, and the amorphous region of cellulose are more susceptible to electrophilic attack by PMS than to reactions involving HO•, SO4•−, or 1O2. Leveraging this distinct mechanism, the extracted MCC demonstrated ultrahigh purity (∼95%) and crystallinity (∼85.36%). Overall, our work involves transforming solid waste into high-value products through the provision of a technical solution, with the potential for onsite application. This represents a significant advancement to the valorization of CMRs, particularly in providing theoretical guidance for accelerating the recycling of waste materials.

Improvement in caffeic acid and ferulic acid extraction by oscillation-assisted mild hydrothermal pretreatment from sorghum straws

This work investigated the effect of oscillation-assisted hydrothermal process on extraction of caffeic acid and ferulic acid from sorghum straws. The results showed that the oscillation-assisted hydrothermal process efficiently improved extraction of caffeic acid and ferulic acid. The oscillation-assisted hydrothermal process resulted in the extraction rates of 1275.48 and 1822.64 mg/L.h for caffeic acid and ferulic acid, respectively. Moreover, the oscillation-assisted hydrothermal process exerted destructive effects on hemicellulose, lignin and the amorphous regions of cellulose, contributing to the release of caffeic acid and ferulic acid in pretreated sorghum straws. The scavenging activities for hydroxyl, 1,1-diphenyl-2-picrylhydrazyl and 2,2′-azino-bis-3-ethylbenzthiazoline-6-sulfonic acid radicals of the caffeic acid and ferulic acid extracts obtained by the oscillation-assisted hydrothermal process were determined to be 83.69 %, 84.17 % and 88.45 %, respectively.

How do the main components influence the VOCs emission characteristics and formation pathways during moso bamboo heat treatment?

Bamboo heat treatment will cause plenty of release of volatile organic compounds (VOCs) into the atmosphere which are important precursors for ozone (O3) formation. In this study, dewaxed bamboo was heat-treated at 180 °C for 2 h to investigate the emission characteristics and the formation pathways of VOCs during heat treatment by removing different main components. The results showed that aldehydes (22.61%–57.54%) and esters (14.64%–38.88%) are the primary VOCs released during heat treatment. These compounds mainly originate from the degradation of hemicellulose, lignin, cellulose, and the linkage bonds between them in bamboo. During the bamboo heat treatment, the degradation of CO, CH, and CO bonds in hemicellulose results in the release of 5-hydroxymethylfurfural, 3-furfural, and 1-(+)-ascorbic acid 2,6-dihexadecanoate. The breakage of benzene ring group and the CO and CH bonds of lignin leading to the emission of VOCs including m-Formylphenol, Vanillin, and Syringaldehyde. The degradation of aliphatic CH, CC, and CO bonds in the amorphous region of cellulose contributes to an enhanced release of alcohols, olefins, and alkanes. It is calculated that acids (28.92%–59.47%), esters (10.10%–22.03%) and aldehydes (17.88%–39.91%) released during heat treatment contributed more to Ozone Formation Potential (OFP).

MOLECULAR DYNAMICS STUDY ON THE EFFECT OF MOISTURE CONTENT ON THE MECHANICAL PROPERTIES OF AMORPHOUS CELLULOSE

The alteration of mechanical properties because of moisture is an inevitable problem in the practical use of cellulosic materials, as well as green and high-performance materials synthesized based on cellulose. Although researchers have analyzed and reported this issue from various aspects, it is necessary to report the variation of mechanical properties of the cellulose system and its causes in detail from the molecular level as well. Herein, the effect of moisture content on the mechanical properties of cellulose is methodically examined by molecular dynamics methods. The main reasons for the structural changes caused by the stiffness and activity space of the cellulose chains and the number of hydrogen bonds in the system are explained and discussed. The obtained results reveal that, in the simulated range of moisture content, low moisture (0 to 4%) exhibits a positive effect on the mechanical properties of the amorphous cellulose region, whereas the effect of high moisture content (4 to 8%) is negative. The mobility of cellulose chains first reduces and then intensifies as the number of water molecules increases, while the rigidity of the corresponding system first increases and then decreases. Additionally, the free volume of the system increases first and then decreases as the number of water molecules rises. The mechanical properties of the amorphous region of cellulose are proportionally correlated with the number of hydrogen bonds in the system. Based on these results, a moisture content of 2% can enhance the properties, increasing the H-bond density in the cellulose network.

Oriented display of cello-oligosaccharides for pull-down binding assays to distinguish binding preferences of glycan binding proteins

The production of biofuels from lignocellulosic biomass using carbohydrate-active enzymes like cellulases is key to a sustainable energy production. Understanding the adsorption mechanism of cellulases and associated binding domain proteins down to the molecular level details will help in the rational design of improved cellulases. In nature, carbohydrate-binding modules (CBMs) from families 17 and 28 often appear in tandem appended to the C-terminus of several endocellulases. Both CBMs are known to bind to the amorphous regions of cellulose non-competitively and show similar binding affinity towards soluble cello-oligosaccharides. Based on the available crystal structures, these CBMs may display a uni-directional binding preference towards cello-oligosaccharides (based on how the oligosaccharide was bound within the CBM binding cleft). However, molecular dynamics (MD) simulations have indicated no such clear preference. Considering that most soluble oligosaccharides are not always an ideal substrate surrogate to study the binding of CBMs to the native cell wall or cell surface displayed glycans, it is critical to use alternative reagents or substrates. To better understand the binding of type B CBMs towards smaller cello-oligosaccharides, we have developed a simple solid-state depletion or pull-down binding assay. Here, we specifically orient azido-labeled carbohydrates from the reducing end to alkyne-labeled micron-sized bead surfaces, using click chemistry, to mimic insoluble cell wall surface-displayed glycans. Our results reveal that both family 17 and 28 CBMs displayed a similar binding affinity towards cellohexaose-modified beads, but not cellopentaose-modified beads, which helps rationalize previously reported crystal structure and MD data. This may indicate a preferred uni-directional binding of specific CBMs and could explain their co-evolution as tandem constructs appended to endocellulases to increase amorphous cellulose substrate targeting efficiency. Overall, our proposed workflow can be easily translated to measure the affinity of glycan-binding proteins to click-chemistry based immobilized surface-displayed carbohydrates or antigens.

High-yield and scalable cellulose nanomesh preparation via dilute acid vapor and enzymatic hydrolysis-mediated nanofabrication

Nanocellulose has received considerable attention in diverse research fields owing to its unique nanostructure-mediated physicochemical properties. However, classical acid hydrolysis usually destroys the microstructural integrity of cellulose, leading to the violent dissociation of cellulose into low-dimensional nanofibers and limiting the formation of intact structures with high specific surface areas. Herein, we have optimized the methodology of dilute acid vapor hydrolysis combined with the enzymatic hydrolysis (DAVE) method and investigated the pore formation mechanism of cellulose nanomesh (CNM). Benefiting from the selective nano-engraving effect of hydrochloric acid vapor on the amorphous region of cellulose followed by widening of the three-dimensional nanopores using enzymatic hydrolysis, confirmed by topographic, spectroscopic, and crystallographic tests, the as-prepared CNM, significantly different from the existing nanocellulose, exhibited improved specific surface area (98.37 m2/g), high yield (88.5 %), high crystallinity (73.4 %), and excellent thermal stability (375.4 °C). The proposed DAVE approach may open a new avenue for nanocellulose manufacturing.

Hydrodynamic cavitation as a promising pretreatment technology to enhance the efficiency of cellulose nanocrystal production via enzymatic hydrolysis

Enzymatic hydrolysis to produce cellulose nanocrystals (CNCs) offers economical and sustainability advantages. However, since this is still an emerging technology, further improvements are needed to make the process feasible for scale-up. In our study, we propose a novel approach using hydrodynamic cavitation (HC) as a pretreatment technology to enhance the efficiency and yield of CNC production. HC treatments conducted under various scenarios induced structural modifications of the cellulose fibers that facilitated their defibrillation and subsequent enzymatic hydrolysis. Isolation through hydrolysis involved the synergistic action of specific enzymes, including xylanase and endoglucanase. Xylanase acted on the hemicellulosic fraction, breaking down the xylan structure and exposing the cellulose fibers. Subsequently, endoglucanase targeted the amorphous regions of cellulose, releasing CNCs. By integrating the HC pretreatment with enzymatic hydrolysis, we achieved remarkable results. High-yield CNCs, reaching approximately 60%, were obtained with a crystallinity index ranging from 81% to 85%. Moreover, this process demonstrated a significant reduction in total energy consumption of approximately 56%, contributing to its economic viability. Furthermore, CNCs with diverse morphologies, aspect ratios, and viscosity profiles were produced, enabling the tailoring of their properties for specific and new applications.

Modification of Cellulosic Materials with Boron-Nitrogen Compounds

Wood fiber and its products are modified to increase fire and bio-resistance. The best results are achieved by using modifiers that enter into chemical interaction with the hydroxylated substrate, forming the organic matrix of the materials. The purpose of the research described in the article was to study the possibility of using boron-nitrogen compounds to modify cellulose and cellulose-containing materials to improve the performance, bio- and fire-protective properties of construction materials, as well as to optimize the consumption of boron-nitrogen compounds. As a result of the research, it was found that the boron-nitrogen compounds used in the compositions developed here chemically interact with hydroxyl groups at the C6-atom of cellulose. The chemical interaction of boron-nitrogen compounds with cellulose is an inter-crystalline process occurring without destruction of the crystal structure of the substrate since the modifier molecules bind with the more accessible hydroxyl groups of the amorphous regions of cellulose. Thus, surface modification with boron-nitrogen compounds does not result in accelerated aging of cellulose-containing materials and loss of strength but, on the contrary, increases the durability of wooden structures.

Molecular Dynamics Simulation of the Effect of Low Temperature on the Properties of Lignocellulosic Amorphous Region

In this paper, a molecular model of cellulose amorphous region-water molecule was developed using Materials Studio software by applying the molecular dynamics method. The effect of low temperature on the properties of the lignocellulosic amorphous region, the main component of wood, was investigated in an attempt to explain the macroscopic property changes from a microscopic perspective and to provide a theoretical basis for the safe use of wood and wood products in low-temperature environments and other related areas of research. Dynamic simulations were carried out at 20 °C, 0 °C, −30 °C, −70 °C, −110 °C and −150 °C for the NPT combinations to obtain the energy, volume, density, and hydrogen bonding change trends of their models, respectively. The changes in the microstructure of the water molecule–cellulose amorphous region model were analyzed, and the mechanical properties were calculated. The results showed that the interaction between the amorphous cellulose region and water molecules was enhanced as the temperature decreased, the density of the models increased, and the volume decreased. The number of total hydrogen bonds and the number of hydrogen bonds between water molecule–cellulose chains increased for each model, and the decrease in temperature made the cellulose molecular activities weaker. The values of G, E, and K increased with the decrease in temperature, and K/G decreased with the decrease in temperature. It shows that the decrease in temperature is beneficial to enhance the mechanical properties of the amorphous region of cellulose and increases the stiffness of the material. However, the toughness and plasticity decrease when the temperature is too low.

Degradation of Chinese handmade papers with different fiber raw materials on molecular and supramolecular structures

As the carriers of paper-based cultural relics, ancient handmade papers have greatly promoted the development of human culture, knowledge and civilization. Chinese papermakers wisely selected a broad variety of plants to make papers with better properties and longer lifetime. However, the correlation between the types of fiber raw materials and the durability of handmade papers is still unclear. Herein, six handmade papers classified as bark paper, bamboo paper and grass paper were selected to study their aging behavior and degradation mechanism. Optical microscope and fiber quality analyzer were used to characterize the fiber morphology and length distribution of papers. The degradation kinetics of six handmade papers were systematically studied under accelerated aging condition. On molecular scale, the degradation rate, variation of pH, oxidation degree, chromaticity, and content of reducing carbonyl groups were discussed for bark, bamboo and grass papers. On supramolecular scale, the crystallinity, energy and distance of hydrogen bonds for paper cellulose were quantitatively calculated. For six handmade papers, most of the degradation occurs in the amorphous region of cellulose, leading to the cleavage of glycosidic bonds, the generation of oxidized groups, and the variation of H-bonds arrangement. Owing to the specific molecular and supramolecular structures of cellulose in bast fiber, bark papers have longer lifetime and better durability than bamboo and grass papers. The results of this work will improve the understanding of paper degradation mechanism at microscopic multiscale structures, and provide the scientific foundation for the preparation of handmade papers with better durability.

Single-molecular insights into the breakpoint of cellulose nanofibers assembly during saccharification

Plant cellulose microfibrils are increasingly employed to produce functional nanofibers and nanocrystals for biomaterials, but their catalytic formation and conversion mechanisms remain elusive. Here, we characterize length-reduced cellulose nanofibers assembly in situ accounting for the high density of amorphous cellulose regions in the natural rice fragile culm 16 (Osfc16) mutant defective in cellulose biosynthesis using both classic and advanced atomic force microscopy (AFM) techniques equipped with a single-molecular recognition system. By employing individual types of cellulases, we observe efficient enzymatic catalysis modes in the mutant, due to amorphous and inner-broken cellulose chains elevated as breakpoints for initiating and completing cellulose hydrolyses into higher-yield fermentable sugars. Furthermore, effective chemical catalysis mode is examined in vitro for cellulose nanofibers conversion into nanocrystals with reduced dimensions. Our study addresses how plant cellulose substrates are digestible and convertible, revealing a strategy for precise engineering of cellulose substrates toward cost-effective biofuels and high-quality bioproducts.

Deterioration of Microstructures and Properties in Ancient Architectural Wood from Yingxian Wooden Pagoda (1056 AD) during Natural Aging

The Yingxian Wooden Pagoda (1056 AD), located in Shanxi province, China, is a unique architectural pure-wooden artifact standing for a millennium. Despite its longevity, the structures and properties of the ancient architectural woods used in its construction have been significantly degraded due to long-term natural aging, which has profoundly impacted the preservation of this valuable cultural heritage. To better understand this degradation, we studied the deterioration of a baluster (Larix principis-rupprechtii Mayr.) from Yingxian Wooden Pagoda. The study employed various analytical techniques, including optical microscopy, atomic force microscopy, Fourier-transform infrared spectroscopy, solid-state 13C nuclear magnetic resonance spectroscopy, X-ray diffraction, and nanoindentation technology, to evaluate the microstructures and properties of the ancient architectural woods. Results indicated that the destruction of wood cell walls was primarily transverse transwall destruction and interfacial debonding and that the degradation of chemical components was primarily in the hemicellulose (xylan) and amorphous region of cellulose. The reduced elastic modulus and hardness of tracheid cell walls in the ancient architectural woods were higher than in recent larch woods. This study would help deepen understanding of wood deterioration during long-term natural aging for the subsequent preservation and protection of wooden cultural heritages and longer use of ancient timber constructions.

Characterization and Prediction of Mechanical and Chemical Properties of Luanta Fir Wood with Vacuum Hydrothermal Treatment.

Since the chemical composition of wood is closely related to its mechanical properties, chemical analysis techniques such as near-infrared (NIR) spectroscopy provide a reasonable non-destructive method for predicting wood strength. In this study, we used NIR spectra with principal component analysis (PCA) to reveal that vacuum hydrothermal (VH) treatment causes degradation of hemicellulose as well as the amorphous region of cellulose, resulting in lower hydroxyl and acetyl group content. These processes increase the crystallinity of the luanta fir wood (Cunninghamia konishii Hayata), which, in turn, effectively increases its compressive strength (σc,max), hardness, and modulus of elasticity (MOE). The PCA results also revealed that the primary factors affecting these properties are the hemicellulose content, hydroxyl groups in the cellulose amorphous region, the wood moisture content, and the relative lignin content. Moreover, the ratios of performance deviation (RPDs) for the σc,max, shear strength (σs,max), hardness, and modulus of rupture (MOR) models were 1.49, 1.24, 1.13, and 2.39, indicating that these models can be used for wood grading (1.0 < RPD < 2.5). Accordingly, NIR can serve as a useful tool for predicting the mechanical properties of VH-treated wood.

Novel Strategy to fabricate Antiwrinkle Cotton fabrics with 1,2,3,4-Butanetetracarboxylic Acid under a Low Temperature.

As a most promising formaldehyde-free crosslinking agent for the antiwrinkle treatment of cotton fabrics, 1,2,3,4-butanetetracarboxylic acid (BTCA) has been explored for many years to replace the traditional N-methylol resin. However, the current methodology for preparing antiwrinkle cotton fabrics with BTCA mainly highlights the troublesome problem of higher curing temperature. In this research, a novel strategy with the aid of dimethyl sulfone (MSM) was developed to decrease the curing temperature of BTCA for fabricating antiwrinkle cotton fabrics, which is an eco-friendly additive with low price and wonderful biocompatibility. Temperature-dependent Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, and computational simulations were employed to analyze the mechanism of MSM in the overall reaction between BTCA and cellulose. Based on the strong hydrogen-bond acceptor property of MSM, the noncovalent interactions in the crosslinking system could be easily interrupted, which facilitates the BTCA diffusion in amorphous regions of cellulose, anhydride formation, and the thermal vibration of cellulose chains during the processing. Physically and chemically speaking, both reactivities of grafting and crosslinking reactions of BTCA are significantly increased with the assistance of MSM, consequently reducing the curing temperature, which will hopefully help achieve the industrial-scale application of BTCA in antiwrinkle treatment.

POWDERED CELLULOSIC MATERIALS: OVERVIEW, CLASSIFICATION, CHARACTERISTICS AND FIELDS OF APPLICATION

Recently, due to the growing interest in powdered cellulosic materials, a large number of studies have been carried out on various methods of their preparation. The main interest is associated with new opportunities for research on nanocellulose. However, for a complete understanding, it is necessary to have information about all powdered cellulosic materials and the peculiarities of their preparation.&#x0D; This paper provides an overview of powdered cellulosic materials, presents their characteristics, and describes the properties of the materials. It is shown that the morphology of its fiber, as well as the ratio of crystalline and amorphous regions of cellulose, has a significant effect on the properties of the material. Peculiarities of obtaining powdered cellulose materials are discussed, depending on the required properties, and existing research in the field of mechanical, chemical and enzymatic processing of cellulose is presented. The main areas of application of various powdered cellulose materials are described, as well as the current situation on the market, examples of both domestic and foreign manufacturers are given. The information on powdered cellulose materials is generalized, their classification is given, which is consistent with the modern concepts described in the scientific works of researchers from all over the world.

Comparative FT-IR Prospecting for Cellulose in Stems of Some Fiber Plants: Flax, Velvet Leaf, Hemp and Jute

Plant fibers are sustainable sources of materials for many industries, and can be obtained from a variety of plants. Cellulose is the main constituent of plant-based fibers, and its properties give the characteristics of the fibers obtained. Detailed characterization of cellulosic fibers is often performed after lengthy extraction procedures, while fast screening might bring the benefit of quick qualitative assessment of unprocessed stems. The aim of this research was to define some marker spectral regions that could serve for fast, preliminary qualitative characterization of unprocessed stems from some textile plants through a practical and minimally invasive method without lengthy extraction procedures. This could serve as a screening method for sorting raw materials by providing an accurate overall fingerprint of chemical composition. For this purpose, we conducted comparative Fourier Transform Infrared Spectroscopy (FT-IR) prospecting for quality markers in stems of flax (Linum usitatissimum L.), velvet leaf (Abutilon theophrasti Medik.), hemp (Cannabis sativa L.) and jute (Corchorus olitorius L.). Analysis confirmed the presence of major components in the stems of the studied plants. Fingerprint regions for cellulose signals were attributed to bands at 1420–1428 cm−1 assigned to the crystalline region and 896–898 cm−1 assigned to the amorphous region of cellulose. The optimization of characterization methods for raw materials is important and can find immediate practical applications.

Elucidation of morphological characteristics, crystallinity, and molecular structures of native and enzyme modified cereal brans.

Bran is a nutritious outermost layer of the cereal grain that is removed during milling to curtail the technical problems in end-products. Modification techniques such as enzyme treatments might be an effective way to alter bran morphology and end-use quality. In this study, bran from six cereals (wheat, barley, oat, maize, millet, and sorghum) were enzymatically modified (cellulase and xylanase), and evaluated for morphological properties through scanning electron microscopy, crystallinity through x-ray diffraction and molecular structures through FTIR spectroscopy. Scanning electron microscopy revealed that enzyme modifications caused breakage in bran fibers by hydrolyzing non-starch polysaccharides. X-ray diffraction exhibited that crystallinity of the structures was increased after modifications as enzymes hydrolyzed amorphous regions of cellulose and hemicellulose in bran matrix. Molecular structures studied by FTIR spectroscopy demonstrated absorption in wavelength ranges of 900-3400cm-1 associated to carbohydrates, oligosaccharides, proteins, and non-starch polysaccharides. PRACTICAL APPLICATIONS: Cereal bran creates technical problems for food processors and bakers in terms of grittiness leading to the unacceptability of the product. The bran can be modified using different approaches, such as enzyme modifications. This research will be helpful for the food scientists & researchers and bakers for making choices for preferred method of bran modification. This will also be helpful for cereal scientists for the understanding of structural properties of bran layers.