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Arabinoxylan is a major hemicellulose in the sugarcane plant cell wall with arabinose decorations that impose steric restrictions on the activity of xylanases against this substrate. Enzymatic removal of the decorations by arabinofuranosidases can allow a more efficient arabinoxylan degradation by xylanases. Here we produced and characterized a recombinant Bifidobacterium longum arabinofuranosidase from glycoside hydrolase family 43 (Bl Abf43) and applied it, together with GH10 and GH11 xylanases, to produce xylooligosaccharides (XOS) from wheat arabinoxylan and alkali pretreated sugarcane bagasse. The enzyme synergistically enhanced XOS production by GH10 and GH11 xylanases, being particularly efficient in combination with the latter family of enzymes, with a degree of synergism of 1.7. We also demonstrated that the enzyme is capable of not only removing arabinose decorations from the arabinoxylan and from the non-reducing end of the oligomeric substrates, but also hydrolyzing the xylan backbone yielding mostly xylobiose and xylose in particular cases. Structural studies of Bl Abf43 shed light on the molecular basis of the substrate recognition and allowed hypothesizing on the structural reasons of its multifunctionality. [Display omitted] [ABSTRACT FROM AUTHOR]

Hemicellulose is mainly distributed in the tightly packed S 2 layer of the plant cell wall and the middle lamella. This rigid microstructure of wood and interactions among hemicellulose, lignin, and cellulose jointly restrict the separation and transformation of hemicellulose in the wood matrix. To address this issue, a method combined with microwave-expanding pretreatment (MEP) and microwave-assisted extraction (MAE) with a NaOH solution was carried out. We found that the MEP could effectively create new pathways for bagasse cells in mass transferring. More specifically, 195 % of the specific surface area (m2/g) with 193 % of the pores (>50 nm) increased after MEP; the SEM images also confirmed that the microstructure of bagasse was modified. MAE could considerably exfoliate hemicellulose from cellulose fiber and accelerate mass transfer. Additionally, we optimized MEP and MAE by using response surface methodology (RSM). The optimal parameters were 370 K, 3.7 min, 1081 W microwave power, and 9.9 wt% NH 4 HCO 3 consumption for the MEP and 1100 W microwave power, 2.5 wt% NaOH concentration, 34.6 min reaction time for MAE, respectively. Moreover, molecular dynamics (MD) simulation suggests that NaOH could significantly lower the work needed to peel off the xylan chain from cellulose nanofibril. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel hydrogel humidity sensor was developed using acrylic acid/bagasse cellulose (AA/BC) porous hydrogel triggered by cold plasma (CP) combining graphene oxide (GO) and embedding citral for antibacterial and intelligent fruit preservation. Results showed that both GO and citral were loaded in AA/BC and had strong hydrogen bond interaction with hydrogel. Acrylic acid/bagasse cellulose/graphene oxide (AA/BC/GO) showed the highest humidity response when the compound concentration of GO was 1.0 mg/mL and the test frequency was 1 kHz, and exhibited high electrical conductivity (−2.6 mS/cm). In addition, in continuous and cyclic relative humidity (RH) tests, the response time of AA/BC/GO from 33.70 % RH to 75.30 % RH was about 177.4 s and the recovery time was about 150.6 s, with excellent sensitivity and durability. The sensors also revealed remarkable antibacterial properties against Escherichia coli and Staphylococcus aureus , among which acrylic acid/bagasse cellulose/graphene oxide-citral (AA/BC/GO-C) was the most prominent, and could extend the shelf life of mangoes for about 8 days. By intuitively judging the appearances and total color difference (TCD) of the hydrogel sensors, it could play the role of intelligent preservation by connecting their water absorption and the release of citral. Therefore, this work provided innovative strategies for the application of hydrogel sensors in food preservation. [Display omitted] [ABSTRACT FROM AUTHOR]

• A new pathway for sustainable CNF isolation from sugarcane bagasse was developed. • Addition of negative charges and lignin removal contribute to fibrillation. • Sonication of highly charged CNF results in CNC with high mass recovery. In this work, cellulose nanofibers (CNF) were obtained from sugarcane bagasse (SC) without high-energy mechanical treatments, using TEMPO-mediated oxidation. Variable NaClO concentrations were used to impart electrostatic repulsion between surface charged groups thus facilitating fibril separation. CNFs with diameters in the 3–5 nm range were obtained by oxidation of SC pulp with NaClO at 25 and 50 mmol/g. After a 30 min –sonication step, these CNFs were broken down into cellulose nanocrystals (CNC) by mechanical action. Both CNF and CNC preparation by this method are possible in SC due to its particular cell wall morphology and were not achieved in eucalyptus biomass, which is more recalcitrant. This work provided thus a new pathway to modulate the final morphology of cellulose particles by combining a low recalcitrant raw material with different surface charge densities. [ABSTRACT FROM AUTHOR]

• Statistical model was used to study effects of hemi structures on material property. • High Xylan/Arabinan ratio is favorable to the material property of hemicelluloses. • High Mw and low lignin is favorable to the material property of hemicelluloses. Using originally isolated xylan-type hemicelluloses for material application suffers from poor mechanical properties including low tensile strength and brittleness. The subsequent chemical modifications of hemicelluloses are facing the problems of high costs and toxic chemicals. Consequently, this study tried to investigate the factors affecting the film-forming properties of the originally isolated xylan-hemicelluloses and promoting their material properties from the extraction step. Two different extraction methods, a one-step alkali or alkaline peroxide solution method and a two-step alkali extraction-delignification method were used to extract the hemicellulose with different chemical structures from sugarcane bagasse. For the two-step alkali extraction-delignification method, hemicelluloses were first extracted by alkali solution and then delignified by dioxane/water, hydrogen peroxide solution or sodium hypochlorite solution. The lignin contents of all the extracted hemicelluloses ranged from 1.6%–9.5%, of which the lowest value was obtained through delignification by sodium hypochlorite. The number average molecular weight ranged from 8200 to 26800, while the xylan/arabinan ratio ranged from 5.0 to 9.1. The hemicelluloses were characterized and processed into films. Tensile strength of films could be considerably improved up to ˜52% when using sodium hypochlorite solution as the delignification agents and the lignin content was greatly reduced for the hemicellulose fraction. Statistical models were generated between film mechanical properties and hemicellulose structural characteristics. The models predicted that hemicellulose with higher molecular weight, more linear structure and lower lignin content would result in better mechanical properties. [ABSTRACT FROM AUTHOR]

Highlights • Enzyme and cold alkali assisted mechanical production of CNF were studied. • Cold alkali pretreatment could change cellulose structure from type I to type II. • Environment-friendly method for preparing high thermal stable CNF was obtained. Abstract In this work, cellulase, low-concentration cold alkali and cellulase combined with cold alkali were used to pretreat unbleached bagasse pulp from which cellulose nanofibrils (CNFs), about 30 nm in diameter, were successfully prepared through ultrafine grinding and high-pressure homogenization. X-ray diffraction analysis showed that cellulase pretreatment increased the crystallinity of CNFs. After low-concentration cold alkali pretreatment, the crystallinity of CNFs significantly reduced and the crystal structure of the cellulose changed from type I to type II. Thermogravimetric analysis showed that CNFs prepared by cellulase combined with cold alkali treatment produced more regenerated cellulose and had lower thermal stability. The use of cellulase and low-concentration cold alkali pretreatments combined with ultrafine grinding and high-pressure homogenization is an environment-friendly method for preparing CNFs. The use of low-concentration cold alkali reduces the consumption of alkali and clean water. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Sulfonated cellulose was derived from agricultural waste; sugarcane bagasse. • The steps of sulfonated cellulose synthesis are affordable and replicable. • Sulfonic acid groups on cellulose increased with amount of potassium metabisulfite. • High water solubility of sulfonated cellulose was successfully achieved. Abstract Sulfonated cellulose (SC) was successfully derived from microcrystalline cellulose (MCC) extracted from sugarcane bagasse, which is a type of agricultural waste. The obtained MCC was first modified by oxidation using sodium periodate in order to cleave the carbon-carbon bonds at the C2 and C3 of the pyranose ring to form 2,3-dialdehyde cellulose. These activated aldehyde groups significantly facilitated the sulfonation carried out using potassium metabisulfite. The sulfonic acid group contents, surface morphology, and water solubility of the obtained products were characterized by titration, field-emission scanning electron microscopy, UV–vis spectroscopy, and zeta potential. High sulfonic acid group content was achieved for the obtained SC samples (i.e., 305–689 μmol/g). The increase in the sulfonic acid group content resulted in the gradual change in the surface morphology and water solubility of the SC samples. The obtained results imply that sugarcane bagasse is a promising raw material for the production of SC with good water solubility. [ABSTRACT FROM AUTHOR]

A nanocomposite comprising crosslinked hybrid polymer network was prepared using chitin and sugarcane bagasse in presence of montmorillonite clay. Chitin and sugarcane bagasse were micro-fibrillated by ultrasonication of their suspension in an ionic liquid 2-hydroxy ethylammonium formate. Optimum reaction conditions were established by variation of amounts of initiator, monomer and crosslinker, and microwave irradiation to obtain nanocomposite with swelling degree above 1000% in 24 h. Slow and steady swelling was observed and the sample swelled to about 15,000% to form a hydrogel in 15 days. The nanocomposite was characterized by swelling degree, infrared spectroscopy, X-ray diffraction and scanning electron microscopy. Swelling and reswelling in water was studied for four cycles, erosion was highest after first cycle but became negligible for consecutive cycles. The swelling degree increased up to three cycles then became constant. Nanocomposite shows sufficient antimicrobial activity against S. aureus and E. coli . It is biodegradable in moist garden soil in three months. [ABSTRACT FROM AUTHOR]

In this study, cellulose of bagasse from Agave tequilana Weber var. azul was extracted to elaborate nanofibers by the electrospinning technique. Fiber characterization was performed using Transmission Electron Microscopy (TEM), x-ray, Fournier Transform-InfraRed (FT-IR) spectroscopy, and thermal analysis by Differential Scanning Calorimetry-Thermogravimetric Analysis (DSC-TGA). Different diameters (ranging from 54.57 ± 0.02 to 171 ± 0.01 nm) of nanofibers were obtained. Cellulose nanofibers were analyzed by means of x-ray diffraction, where we observed a total loss of crystallinity in comparison with the cellulose, while FT-IR spectroscopy revealed that the hemicellulose and lignin present in the agave bagasse were removed. Thermal analysis showed that nanofibers exhibit enhanced thermal properties, and the zeta potential value (−32.5 mV) demonstrated moderate stability in the sample. In conclusion, the nanofibers obtained provide other alternatives-of-use for this agro-industrial residue and could have potential in various industrial applications, among these encapsulation of bioactive compounds and reinforcing material, to mention a few. [ABSTRACT FROM AUTHOR]

Electrohydrodynamic technique (EHD) has lately received considerable attention as an important non-thermal method used for food processing. In this work the effect of EHD on physicochemical properties of cellulose extracted from bagasse was investigated. A three-step process was chosen to extract cellulose fibers, which was performed under a high voltage electric field at the beginning of each step. The cellulose fibers were then characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray Diffraction (XRD), and Thermogravimetric Analysis (TGA). The morphological evaluation revealed that the cellulose fibers have smaller diameter and larger length compared to the microcrystalline cellulose. Moreover, according to the XRD patterns and FTIR spectrum, EHD-treated fibers mainly showed an amorphous structure, and contained a low crystalline fraction. The amorphous structure of cellulose fibers was confirmed by TGA analysis which revealed the presence of higher proportion of amorphous cellulose fraction causes early onset of thermal decomposition. [ABSTRACT FROM AUTHOR]

The aim of the present study is to extract potential thermoplastic polysaccharides from agricultural industrial wastes. Polysaccharides were extracted from renewable agro industrial wastes such as tamarind seeds [rich in starch (TSS)], okra head waste [rich in mucilage polysaccharide (OMP)], sugarcane bagasse [rich in cellulose (SBC)] and residual rice mill wastes [rich in starch and fiber (RS)]. Urigam variety of tamarind seed starch found to be an amylose rich starch. Different polysaccharides extracted from agro wastes were found to be having high thermal stability, except okra polysaccharide (comparatively low). X-ray diffraction pattern of tamarind seed starch proved its high crystallinity index. Crystallinity index of investigated polysaccharides were found to be in the order of SBC > TSS > RS > OMP. Chemical nature of extracted polysaccharides was confirmed by Fourier transform infrared spectroscopic analysis. Residual rice bran starch granules and tamarind seed starch globules were found to be having comparatively reduced particle size than sugarcane bagasse cellulose and okra mucilage. Scanning electron microscopic analysis revealed the cluster formations of RS granules and TSS globules. Residual rice bran starch found to be associated with other fibers (present in outer coat of rice). Okra mucilage and SBC were examined to be having linear sheets and linear bundles structures, respectively. [ABSTRACT FROM AUTHOR]

In the present study, we examined the efficacy of choline acetate (ChOAc, a cholinium ionic liquid))-assisted pretreatment of bagasse powder for subsequent mechanical nanofibrillation to produce lignocellulose nanofibers. Bagasse sample with ChOAc pretreatment and subsequent nanofibrillation (ChOAc/NF-bagasse) was prepared and compared to untreated control bagasse sample (control bagasse), bagasse sample with nanofibrillation only (NF-bagasse) and with ChOAc pretreatment only (ChOAc-bagasse). The specific surface area was 0.83 m 2 /g, 3.1 m 2 /g, 6.3 m 2 /g, and 32 m 2 /g for the control bagasse, ChOAc-bagasse, NF-bagasse, and the ChOAc/NF-bagasse, respectively. Esterified bagasse/polypropylene composites were prepared using the bagasse samples. ChOAc/NF-bagasse exhibited the best dispersion in the composites. The tensile toughness of the composites was 0.52 J/cm 3 , 0.73 J/cm 3 , 0.92 J/cm 3 , and 1.29 J/cm 3 for the composites prepared using control bagasse, ChOAc-bagasse, NF-bagasse, and ChOAc/NF-bagasse, respectively. Therefore, ChOAc pretreatment and subsequent nanofibrillation of bagasse powder resulted in enhanced tensile toughness of esterified bagasse/polypropylene composites. [ABSTRACT FROM AUTHOR]

Three main components of lignocellulose (cellulose, hemicellulose, and lignin isolated from sugarcane bagasse (SCB)) as well as holocellulose and SCB were modified with maleic acid by mechanical activation (MA)-assisted solid phase reaction (MASPR) technology. The order of reactivity was found to be lignin > hemicellulose > cellulose. The amorphous structure of lignin and hemicellulose mainly attributed to their better reactivity, and the modified lignin could reach a maximum degree of esterification (DE) of 93.45%. MA improved the accessibility and reactivity of cellulose, as the DE of modified cellulose gradually increased with milling time and reached the maximum value of 57.30% at 120 min, which had significant effect on structure changes and DE of modified holocellulose and SCB. MA enhanced the esterification of all three components in lignocellulose with relatively high substituent distribution in them, and maleated SCB with a maximum DE of 64.17% was successfully prepared by this simple, green, and effective MASPR technology. [ABSTRACT FROM AUTHOR]

Bagasse is a waste product of sugar extraction from sugar-cane with approximately 30% cellulose content. Cellulose was successfully extracted from sugar-cane bagasse using a modified mercerization-bleaching approach with a 40% yield. Extracted cellulose was converted to cellulose acetate for enhanced electrospinnability and blended with poly- l -Lactide or polydioxanone before solution electrospinning. Physico-chemical evaluation of the electrospun mats showed variable miscibility of blends. In vitro cell studies with L929 mouse fibroblast cells was quite conclusive as regards the biocompatibility of the blended mats with proliferative behavior of cells, extracellular matrix deposition and characteristic features of healthy cellular response. MTT assay indicated that the cellulose blended mats induced higher cell densities than the controls. Cellulose content influenced parameters such as fiber diameter, porosity and cell-matrix interaction of mats impacting on cell growth and behavior. Preliminary assessment of biomineralization potential of the mats by SEM showed nano-hydroxyapatite deposits on the electrospun fibers. [ABSTRACT FROM AUTHOR]

Understanding the interaction mechanisms between xylan and xylan-degrading enzymes is beneficial to the efficient hydrolysis of xylan. Xylan from sugarcane bagasse (SB) was extracted and characterized. The effects of heat treatment and removal of side chains of SB xylan on the hydrolytic efficiency and synergistic action of endo-β-1,4-xylanases (HoXyn11A and AnXyn10C), β-xylosidases (AnXln3D), and α- l -arabinofuranosidases (AnAxh62A) were investigated. Results indicated that heat treatment of xylan can improve the hydrolytic efficiency of xylan-degrading enzymes, and it is essential for the efficient hydrolysis of xylan by HoXyn11A. The removal of arabinofuranosyl side chains of xylan by AnAxh62A before enzymatic hydrolysis reduced the hydrolytic efficiency of HoXyn11A and AnXyn10C on xylan. AnXyn10C was more efficient than HoXyn11A in hydrolysis of xylan, whereas HoXyn11A showed better synergistic action than AnXyn10C with AnAxh62A and AnXln3D in the hydrolysis of xylan. This study provides new insights on the enzymatic hydrolysis of SB into monosaccharides and xylo-oligosaccharides. [ABSTRACT FROM AUTHOR]

The environmental and technical feasibility of cellulose nanocrystal production from sugarcane bagasse fibers was evaluated. First, the life cycle assessment (LCA) is presented as a methodology to investigate the most feasible form of obtainment. The environmental impacts regarding climate change and water footprint were evaluated considering a gate-to-gate process and a functional unit of 1 kg. The inventory data encompassed sugarcane plantation and pretreatment, bleaching and hydrolysis for bagasse generation. The twelve scenarios for extracting nanocrystals that were investigated consisted of treatment with sodium hydroxide or sodium chlorite followed by sulfuric acid hydrolysis. All products and processes were characterized by their yield and X-ray diffraction. As a result, all scenarios showed that the pretreatment stage was the most important contributor to the environmental impact. The comparison among the scenarios showed that nanocrystals produced by processes V – NaClO 2 /NaOH/H 2 SO 4 /30 min/1x and IX – NaClO 2 /NaOH/HNO 3 /H 2 SO 4 /30 min/1x presented low water consumption and minimal contributions to climate change. Therefore, considering the LCA, yield and crystallinity, the best processes were V and IX sequences. Finally, these cellulose nanocrystals were evaluated by their chemical composition, morphology and thermal stability, exhibiting hemicellulose and lignin removal, nanometric dimensions from 8 to 12 nm, high crystallinity and low thermal stability. [ABSTRACT FROM AUTHOR]

The sugarcane bagasse was used for producing carboxymethyl cellulose (CMC) and obtaining high-molecular-mass hemicellulose as co-product. To this end, the steam explosion process was employed. It was found that the optimum operating conditions are the temperature of 187.15 °C, NaOH/bagasse ratio of 39% (w/w), and retention time (RT) of 10 min. Next, the obtained cellulose in the optimized condition was extracted and purified, and it was subsequently converted to CMC according to Williamson etherification technique. This paper also employed response surface methodology (RSM) to model effective factors against a degree of substitution (DS). Based on it, the optimum values of independent variables are the NaOH concentration of 28.4%, MCA mass of 1.14gram, temperature of 57.85 °C, and reaction time of 4.01 h which the CMC had the DS of 1.085, the yield of 181.302%, purity of 71.6%, and crystallinity of 30.1% with low viscosity. Samples comparatively studied by FT-IR, TGA and XRD. [ABSTRACT FROM AUTHOR]

The purpose of this study is to explore the suitability of bagasse fiber for production of Cellulose Nanofiber (CNF) and Oriented Cellulose Nanopaper (OCNP) for the first time. Different types of CNF were thus produced either mechanically by homogenization or with enzymatic pre-treatment followed by homogenization. The CNF was thereafter used for the production of nanopapers through two approaches; i) Dispersion Casting (DC) and ii) Dynamic Sheet Former (DSF). Then, the prepared nanopapers were characterized in terms of surface, structural, morphological and mechanical properties. It was found that compared to DC method, the OCNP had higher crystallinity as well as superior tensile and tear indices. The results also showed that the highest tensile strength index value of 189 N m/g was measured for the OCNP at the Machine Direction (MD).This would most probably be attributed to the presumptive anisotropic orientation of the nanofibrils due to the shearing forces induced from the DSF. These unique characteristics of the OCNP are promising for potential applications in food packaging. [ABSTRACT FROM AUTHOR]

The phthalation of bagasse was comparatively investigated with the isolated three main components in 1-allyl-3-methylidazium chloride (AmimCl) to reveal the reaction behavior of bagasse. In the present study, the reaction behavior of hemicelluloses during the homogeneous phthalation was extensively explored. The phthalation degree of hemicellulosic samples ranged from 16.37% to 52.14%. The reaction priority on the main and side chains of hemicelluloses were revealed by the changes of monosaccharide contents upon phthalation. The results indicated that side-chains of hemicelluloses were more easily phthalated than main-chains, and the phthalation of secondary hydroxyl groups on uronic acids was more difficult than that on neutral sugars. 13 C NMR and HSQC analyses suggested the similar reactivity of the secondary hydroxyls at C-2 and C-3 positions in anhydroxylose units. These results provide more detailed understanding of the homogenous modification of lignocellulose. [ABSTRACT FROM AUTHOR]

In our study we used holocelluloses from sugar beet and bagasse for film preparation. Films from sugar beet holocellulose have better mechanical properties than from bagasse holocellulose. By subsequent carboxymethylation of bagasse holocellulose, films with better properties were produced. Specimens prepared from combined sugar beet and bagasse carboxymethylated holocellulose had the best mechanical properties. The results could be explained by the ratios of cellulose, arabinan, polygalacturonan and xylan content in individual films, based on the elemental analysis data. The use of microwaves to prepare holocellulose film speed up the process, but negatively affected the mechanical properties. Lignin content of the sugar beet holocellulose and bagasse samples was low and did not affect the mechanical properties. Both types of agricultural by-products could be used for preparation of composite film with high strength and stiffness suitable for broad range of applications. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse and straw are generated in large volumes as by-products of agro-industrial production. They are an emerging valuable resource for the generation of hemicellulose-based materials and products, since they contain significant quantities of xylans (often twice as much as in hardwoods). Heteroxylans (yields of ca 20% based on xylose content in sugarcane bagasse and straw) were successfully isolated and purified using mild delignification followed by dimethyl sulfoxide (DMSO) extraction. Delignification with peracetic acid (PAA) was more efficient than traditional sodium chlorite (NaClO 2 ) delignification for xylan extraction from both biomasses, resulting in higher extraction yields and purity. We have shown that the heteroxylans isolated from sugarcane bagasse and straw are acetylated glucuronoarabinoxylans (GAX), with distinct molecular structures. Bagasse GAX had a slightly lower glycosyl substitution molar ratio of Ara f to Xyl p to (0.5:10) and (4- O -Me)Gl p A to Xyl p (0.1:10) than GAX from straw (0.8:10 and 0.1:10 respectively), but a higher degree of acetylation (0.33 and 0.10, respectively). A higher frequency of acetyl groups substitution at position α-(1 → 3) (Xyl-3Ac) than at position α-(1 → 2) (Xyl-2Ac) was confirmed for both bagasse and straw GAX, with a minor ratio of diacetylation (Xyl-2,3Ac). The size and molecular weight distributions for the acetylated GAX extracted from the sugarcane bagasse and straw were analyzed using multiple-detection size-exclusion chromatography (SEC-DRI-MALLS). Light scattering data provided absolute molar mass values for acetylated GAX with higher average values than did standard calibration. Moreover, the data highlighted differences in the molar mass distributions between the two isolation methods for both types of sugarcane GAX, which can be correlated with the different Ara f and acetyl substitution patterns. We have developed an empirical model for the molecular structure of acetylated GAX extracted from sugarcane bagasse and straw with PAA/DMSO through the integration of results obtained from glycosidic linkage analysis, 1 H NMR spectroscopy and acetyl quantification. This knowledge of the structure of xylans in sugarcane bagasse and straw will provide a better understanding of the isolation-structure-properties relationship of these biopolymers and, ultimately, create new possibilities for the use of sugarcane xylan in high-value applications, such as biochemicals and bio-based materials. [ABSTRACT FROM AUTHOR]

It is advantageous to understand the relationship between cellulose fiber morphology and the rheological behavior of its dispersions so that their application can be optimized. The goal of this study was to produce sugarcane bagasse-sourced cellulose dispersions with different numbers of high-pressure homogenization cycles. Microfluidization produced cellulose nanofibers (between 5 and 80 nm in diameter) with similar surface charge densities and crystallinities (measured on the resulting films). Oscillatory rheology showed that TEMPO-oxidized cellulose dispersions exhibited gel-like behavior. However, not only did the samples with more microfluidization cycles present a lower storage modulus, but the sample with 100 cycles completely lost the gel-like characteristic, presenting a viscous fluid rheological behavior. Thixotropy loop tests revealed the influence of nanofiber length on the dispersion's structure, as evidenced by the decrease in the hysteresis value along with fiber breakage. Therefore, our findings demonstrate that the rheological properties of the dispersion can be tuned according to the length of the nanofibers, allowing for targeted applications. [Display omitted] [ABSTRACT FROM AUTHOR]

The scCO 2 -assisted organosolv pretreatment of sugarcane bagasse was carried out using aqueous ethanol and organic acid catalysts. Variables involved were temperature (150–190 °C), time (0–60 min), type of catalyst (acetic, citric, and oxalic acids), amount of CO 2 (25–50 g), ethanol titer in water (0–80 vol%), and catalyst concentration (0.5 to 1.5 % w·v−1). The best delignification (86 wt%) and glucan retention (89 wt%) were achieved at 170 °C for 15 min using 60 vol% ethanol in water, 1 wt% oxalic acid, and 25 g CO 2. Organic acid esterification was a limitation for pretreatment operations using ethanol titers above 60 vol%. Enzymatic hydrolysis of pretreated materials at 1 % (w·v−1) glucans released 74.3 ± 0.2 % glucose in 96 h using Cellic CTec3 (Novozymes) at 9.89 FPU·g glucans −1. The concentrated pretreatment liquor allowed lignin recovery by water precipitation in high yields, while the aqueous supernatant contained low levels of fermentation inhibitors. [Display omitted] [ABSTRACT FROM AUTHOR]

Cellulose triacetate (CTA) films were produced from cellulose extracted from sugarcane bagasse. The films were characterized using scanning electron microscopy (SEM), water vapor permeability (WVP), mechanical properties (MP), enzymatic digestion (ED), and mucoadhesive properties evaluation (MPE). WVP showed that more concentrated films have higher values; asymmetric films had higher values than symmetric films. MP showed that symmetric membranes are more resistant than asymmetric ones. All films presented high mucoadhesiveness. From the WVP and MP results, a symmetric membrane with 6.5% CTA was selected for the coating of gellan gum (GG) particles incorporating ketoprofen (KET). Thermogravimetric analysis (TGA) showed that the CTA coating does not influence the thermal stability of the particles. Coated particles released 100% of the KET in 24 h, while uncoated particles released the same amount in 4 h. The results highlight the CTA potential in the development of new controlled oral delivery systems. [ABSTRACT FROM AUTHOR]

Biorefinery with deep eutectic solvent (DES) is an emerging processing technology to overcome the shortcomings of conventional biomass pretreatments. This work evaluates the biorefinery of sugarcane bagasse (SCB) with DES formulated with choline chloride as hydrogen bond acceptor and three hydrogen bond donors: lactic acid, citric acid, and acetic acid. Acetic acid showed unique ionic properties responsible for the selective removal of lignin and the deconstruction of cellulose to improve the digestibility of up to 97.61 % of glucan and 63.95 % of xylan during enzymatic hydrolysis. In addition, the structural characteristics of the polysaccharide-rich material (PRM) were analyzed by X-rays, ATR-FTIR, SEM, and enzymatic hydrolysis, and compared with the original material sample, for a comprehensive understanding of biomass deconstruction using different hydrogen bond donors (HBD) as DES pretreatment. [Display omitted] • SCB was pretreated with DES using different organic acid as HBD to improve its digestibility. • [ChCl]:AA promotes the application of mild operational condition that increases the fermentable sugars released. • [ChCl]:AA promotes deconstruction of SCB through changes in functional groups and morphological modifications. • 97.61% of glucan digestibility was developed after [ChCl]:AA pretreatment. • The selective fraction of lignin by [ChCl]:LA does not achieve the best enzymatic saccharification in SCB. [ABSTRACT FROM AUTHOR]

Most technologies to produce multifunctional paper involved the defect of poor uniformity and stability. Herein, a high stability multi-functional cellulose-based paper was developed via a multiple chemical modification derived from waste bagasse. Firstly, the acetoacetyl groups was anchored on the surface of bagasse cellulose fibers by a heterogeneous transesterification. Then, paper was made based on these modified fibers. The fluorophore and gentamicin sulfate (Gen) were bonded in-situ to the paper through Hantzsch reaction and the form of enamine bond, respectively. The resulting paper exhibited excellent multifunctional properties, such as fluorescence property, antibacterial property and hydrophobic property. These properties are very stable to external environments. In addition, relatively mild surface modification has no obvious effect on fibers and shows similar whiteness and stiffness properties as that of the CAA paper. Thus, these novel functional papers held great potential for many fields such as food packaging, anti-counterfeiting, and other specialty papers. [Display omitted] • Multifunctional paper was fabricated via multiple chemical modification. • Modification showed no effect on whiteness and stiffness properties of CAA paper. • The covalent bond connection endowed paper stable to external environments. • Multifunctional paper held great potential for many fields. [ABSTRACT FROM AUTHOR]

Two kinds of carboxylated cellulose nanocrystals (CCNs) were prepared by using ultrasonic assisted 2,2,6,6-tetramethylpiperidinyl-1-oxy radical (TEMPO) mediated oxidation and one-step ammonium persulfate (APS) oxidation, which were denoted as TEMPO-oxidized CCNs (TO-CCNs) and APS-oxidized CCNs (AO-CCNs), respectively. The effects of oxidant content on the yield, carboxyl content, degree of polymerization (DPv) and morphology of the oxidized celluloses in the two oxidation methods were studied. Furthermore, the chemical structure, crystallinity and thermal stability of TO-CCNs and AO-CCNs were evaluated and compared by Fourier transformed infrared spectra, X-ray diffraction and thermogravimetric analyses. The results showed that with increase of oxidant content in the two methods, the carboxyl groups on the surfaces of TO-CCNs and AO-CCNs were both improved. And a remarkable decline of the DPv of cellulose sample also appeared in the two oxidative treatments. In addition, AO-CCNs exhibited a higher crystallinity and an enhanced thermal stability compared with TO-CCNs. [ABSTRACT FROM AUTHOR]

The present study deals with the production of cellulosic ethanol from bagasse using the synthesized TiO 2 coupled nanocellulose (NC-TiO 2 ) as catalyst. Aspergillus nidulans AJSU04 cellulase was used for the hydrolysis of bagasse. NC-TiO 2 at various concentrations was added to bagasse in order to enhance the yield of reducing sugars. Complex interaction between cellulase, bagasse, NC-TiO 2 and the reaction environment is thoroughly studied. A mathematical model was developed to describe the hydrolysis reaction. Ethanol production from enzymatically hydrolyzed sugarcane bagasse catalyzed with NC-TiO 2 was carried out using Saccharomyces cerevisiae ATCC 20602. The glucose release rates and ethanol concentrations were determined. Ethanol produced was found to be strongly dependent on pretreatment given, hydrolysis and fermentation conditions. The study confirmed the promising accessibility of NC-TiO 2 , for enhanced glucose production rates and improved ethanol yield. [ABSTRACT FROM AUTHOR]

Cellulose isolation, a promising way for lignocellulosic biomass utilization, is always restricted by the poor solubility of cellulose. In this paper, tetra-n-methylammonium hydroxide (TMAH) was confirmed to be capable of readily dissolving/regenerating cellulose without chemical modification at room temperature. Meanwhile, cellulose isolation from lignocellulosic biomass by initially dissolving the biomass in TMAH followed by cellulose precipitation was proposed, and the isolated substance with average cellulose purity of 92.1 ± 0.3% could be obtained throughout this process under the optimum conditions: temperature 52 °C, time 60 min, and loading ratio of TMAH/biomass ( w / w ) 7.2:1. Besides, high efficiency cellulose isolation (i.e. >70% cellulose purity) could be continuously remained during 4-round cycles by using the recycled TMAH solvent without distinct activity loss. [ABSTRACT FROM AUTHOR]

Cellulose I, cellulose II and cellulose I/II hybrid fibers were prepared from energycane bagasse using NaOH and NaClO 2 treatments. The definitive defibrillation effect with an average width of 12 ± 5 μm was observed for the fibers treated with 20 wt% NaOH for 10 h and NaClO 2 for 2 h. The ribbon shaped cellulose I fibers were converted to a swollen state with a rougher surface by 20 wt% NaOH treatment for 10 h. The percentage of cellulose I decreased from 100% to 5%, and the corresponding CI values increased from 58.2% to 68.8% during the conversion from cellulose I to II. After further NaClO 2 treatment, the CI values were decreased because of partial destruction of hydrogen bond network. XRD, NMR and FTIR results present the same trend in the degree of crystallization for all the samples. [ABSTRACT FROM AUTHOR]

α -l- Arabinofuranosidase (AbfB) and novel α- d -glucuronidase (Agu1B) enzymes were applied for selective hydrolysis of beechwood ( Fagus sylvatica ) xylan (Sigma–Aldrich) as well as xylans extracted from Eucalyptus grandis and sugarcane ( Saccharum officinarum L.) bagasse, leading to precipitation of these carbohydrate biopolymers. Hemicellulose extraction was performed with two mild-alkali methods, Höije and Pinto. Precipitation occurred after removal of 67, 40 and 16% 4- O -methyl- d -glucuronic acid (MeGlcA) present in polymeric xylans from beechwood, E. grandis (Pinto) and E. grandis (Höije), respectively. Precipitation was maximized at Agu1B levels of 3.79–7.53 mg/g substrate and hemicellulose concentrations of 4.5–5.0% (w/v). Polymeric xylan from sugarcane bagasse precipitated after removal of 48 and 22% of arabinose and MeGlcA, respectively, at optimal AbfB and Agu1B dosages of 9.0 U/g and 6.4 mg/g, respectively. Both the purity of polymeric xylans and structure thereof had a critical impact on the propensity for precipitation, and morphology of the resulting precipitate. Nano-to micro-meter precipitates were produced, with potential for carbohydrate nanotechnology applications. [ABSTRACT FROM AUTHOR]

In this study, sugarcane bagasse was pretreated with acid-catalyzed alcohols, i.e., ethanol (AE), ethylene glycol (AEG) and glycerol (AG) to prepare pulps for producing lignin-containing cellulose nanofibrils (LCNF) with tailored properties, such as hydrophilicity/hydrophobicity and dispersion stability. The results showed that AG-LCNF had the highest lignin content of 16% but relatively low hydrophobicity while AE-LCNF had a low lignin content of 11% but the highest hydrophobicity. LCNF diameter distribution, crystallinity, zeta potentials and thermal stability were also determined to understand the effects of pretreatment solvent. NMR analyses revealed that alcohols modified lignin at α -position by etherification and γ -position by esterification of aliphatic chains, subsequently affecting lignin oxidation by TEMPO in the LCNF production processes, LCNF properties and LCNF dispersion in different solvents. This study provided fundamental information in the design and tailored production of LCNF for various applications, such as manufacturing polymer composites and Pickering emulsions. [Display omitted] [ABSTRACT FROM AUTHOR]

Lignin-containing cellulose nanofibrils (LCNFs) with tunable lignin contents from sugarcane bagasse were directly prepared by low-temperature soda‑oxygen pulping combined with simple mechanical treatment. The residual lignin structure, morphology and physical dimensions of LCNFs, and properties of the relevant cellulose nanopapers (CNPs) were investigated. In situ 2D Heteronuclear Single Quantum Coherence (HSQC) NMR spectra showed β–O–4 linkages, ferulate, and para-coumarate were well preserved in the LCNFs. Compared with the cellulose nanofibrils (CNFs), LCNFs displayed a more uniform size and narrow diameter distribution. The corresponding CNPs exhibited outstanding mechanical properties (tensile strength reached 152.9 MPa), and excellent combined optical properties both in the UV blocking and visible light transparency. Moreover, the water contact angles (50.0–80.2°) of LCNFs were much higher than that of CNFs (21.7°). Direct preparation of LCNFs under mild condition would unlock the full potential of cellulosic materials and provide enhanced opportunities for cellulose to fabricate multi-functional and high-value materials. [Display omitted] • LCNFs with tunable lignin contents were prepared by mild soda-oxygen pulping. • Residual lignins in LCNFs were structurally much close to that of native lignin. • LCNFs exhibited more uniform sizes and narrower diameter distributions than CNFs. • CNPs produced from LCNFs showed improved multi-functional properties. [ABSTRACT FROM AUTHOR]

This study designed and synthesized a novel cellulose-based heavy metal adsorption material. One kind of bagasse pulp cellulose was pretreated under microwave 200 W for 3 min before the epoxidation, amination and ultrasonic enhancement sulfonation reaction. Heavy metal adsorption groups N and S were grafted onto the bagasse pulp cellulose. Furthermore, the effects of solution pH, adsorption temperature, adsorbent dosage, Cu 2+ concentration, and adsorbent recycling on adsorption capacity were investigated. Under the optimum condition, the adsorption amount of Cu 2+ was 35.2 mg/g adsorbent. Compared with other cellulose-based adsorbents, this kind of adsorbent could be easily prepared and effectively recycled. Except for the normal fitting of adsorption process with the Langmuir isotherm adsorption model, Freundlich isotherm adsorption model and secondary adsorption kinetics model, the solid–liquid phase adsorption mechanism was also introduced to explain the Cu 2+ adsorption process. Three consecutive stages were deeply discussed and verified, where the surface diffusion and particle internal diffusion process were the primary along with a quick adsorption of the adsorbate onto the in-hole surface of the cellulose-based adsorbent. [ABSTRACT FROM AUTHOR]

The aim of this research was to enhance the survivability of Lactobacillus rhamnosus NRRL 442 against heat exposure via a combination of immobilization and microencapsulation processes using sugarcane bagasse (SB) and sodium alginate (NaA), respectively. The microcapsules were synthesized using different alginate concentration of 1, 2 and 3% and NaA:SB ratio of 1:0, 1:1 and 1:1.5. This beneficial step of probiotic immobilization before microencapsulation significantly enhanced microencapsulation efficiency and cell survivability after heat exposure of 90 °C for 30 s. Interestingly, the microcapsule of SB-immobilized probiotic could obtain protection from heat using microencapsulation of NaA concentration as low as 1%. SEM images illustrated the incorporation of immobilized L. rhamnosus within alginate matrices and its changes after heat exposure. FTIR spectra confirmed the change in functional bonding in the presence of sugarcane bagasse, probiotic and alginate. The results demonstrated a great potential in the synthesis of heat resistant microcapsules for probiotic. [ABSTRACT FROM AUTHOR]

Sugarcane bagasse (SCB) was grafted with acrylamide (AAm) and glycidyl methacrylate (GMA) by chemical oxidation method. The effect of monomer/initiator molar ratio, reaction time, reaction temperature and material to liquor ratio on the degree of grafting was investigated. The optimum conditions for grafting were: monomer/initiator molar ratio 1 for AAm and 2 for GMA, reaction time 4 h, reaction temperature 80 °C and materials to liquor ratio 1:20. Silver nanoparticles (AgNPs) were prepared and characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). Ungrafted SCB, SCB-g-AAm and SCB-g-GMA were impregnated into silver (Ag) nanoparticles colloidal solution. The ungrafted SCB, grafted SCB and their nanocomposites with Ag nanoparticles were characterized by FT-IR spectroscopy, X-ray diffraction (XRD) and scanning electron microscopy (SEM). The grafted SCB/Ag nanoparticles exhibit better antimicrobial activity against Escherichia coli as the model Gram-negative bacteria, Staphylococcus aureus as the model Gram-positive bacteria and Aspergillus flavus and Candida albicans (yeasts) than ungrafted SCB/AgNPs. [ABSTRACT FROM AUTHOR]

Two fractions of sugarcane, namely bagasse and straw (or trash), were characterized in relation to their chemical composition. Bagasse presented values of glucans, hemicelluloses, lignin and ash of 37.74, 27.23, 20.57 and 6.53%, respectively, while straw had 33.77, 27.38, 21.28 and 6.23% of these same components. Ash content was relatively high in both cane biomass fractions. Bagasse showed higher levels of contaminating oxides while straw had a higher content of alkaline and alkaline-earth oxides. A comparison between the polysaccharide chemical compositions of these lignocellulosic materials suggests that similar amounts of fermentable sugars are expected to arise from their optimal pretreatment and enzymatic hydrolysis. Details about the chemical properties of cane biomass holocellulose, hemicelluloses A and B and α-cellulose are provided, and these may offer a good opportunity for designing more efficient enzyme cocktails for substrate saccharification. [ABSTRACT FROM AUTHOR]

Nanocelluloses were prepared from sugarcane bagasse celluloses by dynamic high pressure microfluidization (DHPM), aiming at achieving a homogeneous isolation through the controlling of shearing force and pressure within a microenvironment. In the DHPM process, the homogeneous cellulose solution passed through chambers at a higher pressure in fewer cycles, compared with the high pressure homogenization (HPH) process. X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) demonstrated that entangled network structures of celluloses were well dispersed in the microenvironment, which provided proper shearing forces and pressure to fracture the hydrogen bonds. Gel permeation chromatography (GPC), CP/MAS 13 C NMR and Fourier transform infrared spectroscopy (FT-IR) measurements suggested that intra-molecular hydrogen bonds were maintained. These nanocelluloses of smaller particle size, good dispersion and lower thermal stability will have great potential to be applied in electronics devices, electrochemistry, medicine, and package and printing industry. [ABSTRACT FROM AUTHOR]

The enzymatic hydrolysis of native starch lacks efficiency because starch is mostly confined in semi-crystalline granules. To address the challenges associated with gelatinization and render native cassava starch (CS) amenable to enzymatic hydrolysis (enzyme cocktail from Aspergillus awamori and Trichoderma reesei), dry-extrusion pretreatment of CS mixed with sugarcane bagasse (SB) was studied. Results showed that among the CS:SB mass ratios studied (1:1; 1:0.5 and 1:0.25), extruded CS:SB (1:0.25) gave the highest 3-hour glucose yield (71.5%) after enzymatic hydrolysis. Extrusion reduced CS:SB (1:0.25) crystallinity by 78% and increased the intensity of all major FTIR absorption bands by 67–202%. The optimum 3-hour glucose yield from extruded CS:SB (1:0.25) hydrolysis was 74.1%, which was 330% higher than from untreated CS. The water absorption and solubility indices of the treated biomass increased by 145% and 12,640%, respectively under the optimum conditions, aiding the hydrolysis process. The dry extrudates were easy to manipulate and store. [Display omitted] [ABSTRACT FROM AUTHOR]

Arabinoxylan is one of the main components of xylan-rich hemicellulose of sugarcane bagasse. The study on the dissolution behavior of arabinoxylan from sugarcane bagasse (AXSB) is beneficial to its efficient utilization. The dissolution behavior of AXSB in a 50% TBAH aqueous solution was investigated by small angle X-ray scattering and rheological methods. SAXS analysis showed that the radius of gyration (R g) of AXSB is between 8.5 nm and 21.6 nm, and R g has a larger value with the rising AXSB concentration. Rheological measurements showed that AXSB is completely dissolved in TBAH aqueous solution at low concentration, aggregating after reaching a certain concentration. The estimated critical concentration is approximately 0.033 g mL−1. The rheological curves at the high concentration indicated shear thinning behavior, causing the failure of the Cox-Merz rule. The storage modulus grows gradually with the increasing AXSB concentration, inferring the probable formation of AXSB aggregation in TBAH aqueous solution. [Display omitted] [ABSTRACT FROM AUTHOR]

Highlights: [•] Cellulose nanocrystals (CNC) were obtained from sugarcane bagasse. [•] Starch films and starch/CNC were formulated and their water barrier properties were tested. [•] CNC addition increases the surface hydrophobicity of starch films. [•] CNC incorporation improves water barrier properties of starch films. [•] The effect on permeation process was studied through phenomenological analyses. [Copyright &y& Elsevier]

Highlights: [•] Cellulose nanofiber was satisfactorily produced by grinding process from bagasse. [•] All-cellulose nanocomposite was suitably produced by partial dissolution method. [•] All-cellulose nanocomposite film displayed a maximum tensile strength of 140MPa. [•] Thermal stability of ACNC decreased according to the partial dissolution process. [•] Water vapor permeability increased with an increased duration of dissolution time. [Copyright &y& Elsevier]

Highlights: [•] Hot compressed water extraction of high hemicellulose yields in short reaction times. [•] Minimal hemicellulose degradation products and lignin in the extraction liquor. [•] Successful application of membranes for concentration of high purity hemicelluloses. [ABSTRACT FROM AUTHOR]