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Complete utilization of different agricultural wastes is a great challenge before human society. The present study reports the valorization of rice straw for simultaneous production of reducing sugars and paper. The rice straw was first pre-extracted with water under different reaction conditions sequentially followed by papermaking. A maximum total reducing sugars (TRS) upto 12.38 % was extracted through aqueous pre-treatment. The pulped biomass was assessed for paper properties viz., tensile index, tear index, burst index, Kappa no. and brightness. For untreated rice straw tensile index, tear index and burst index were recorded within a range of 30.9–35.8 N m/g; 2.25–2.62 mN m2/g and 1.91–2.35 kN/g respectively where as it were ranged from 31.1 to 33.7 N m/g, 2.02–2.51 mN m2/g and 1.78–2.08 kN/g respectively for pretreated rice straw. Moreover, for untreated rice straw, kappa number and brightness were recorded in a range from 20.7 to 26.6 and 32.4 to 36.7 % ISO respectively, whereas for pre-treated rice straw it ranged from 19.1 to 26.3 and 31.6 to 35.5 % ISO respectively. High performance liquid chromatography (HPLC) analysis and field emission gun scanning electron microscopy (FESEM) were further employed during the study. In overall, extraction of underutilized sugars prior to pulping may prove as an efficient route for apt utilization of sugars followed by papermaking in near future. [ABSTRACT FROM AUTHOR]

The purpose of this study was to clarify whether the wood grinding model -- based on an energy balance for the grinding zone -- would improve understanding of wood grinding for pulp. This study relied on previously obtained data by the Finnish Pulp and Paper Research Institute. The frictional coefficient (Pc/Pt) computed and the power-specific groundwood production (Ġw/Pt) were important x- and y- variables, respectively. Fresh spruce wood samples were ground by application of a laboratory grinder, where the stone surface speeds were 30, 15 and 7 m/s, respectively. The power-specific productivities of high- and medium-speed grindings followed one and the same mechanism, since both speeds led to a productivity of 0.99 [(kg/h)/kW]; the low-speed grinding, however, led to a level of 0.66 [(kg/h)/kW] at frictional coefficients closest to 100 mW/kW. The rate of formation of coarse rejects was -- at the same frictional coefficient as before -- 15.0, 4.3 and 2.3 mg/s for high-, medium- and low-speed grindings, respectively. However, the rate of fines formation determined by McNett apparatus was about ten times higher than that of formation of coarse rejects: 123.0, 42.2 and 23.7 mg/s, respectively. The fines-to-shives ratio (determined by a Somerville shive analyser) was assumed to indicate fiberisation for high-, medium- and low-speed grindings, and the true data, most close to 100 mW/kW, were 56.0, 55.9 and 36.1 units of fines-to-shives, respectively. The curves followed the same trend, but on slightly different levels. As for the important sheet properties, the tensile strengths of high-, medium- and low-speed grindings were low, medium and high, respectively: 37.1, 46.9 and 56.2 Nm/g. The light scattering coefficients of high-, medium- and lowspeed grindings were low, medium and high, respectively, or as data being most close to 100 mW/kW: 59.2, 66.0 and 67.5 m2/kg, respectively. Some general conclusions may be drawn from these results. To achieve the best groundwood productivity, the frictional coefficient should be kept on a level close to 100 mW/kW. Generally speaking, it seems that high- and medium-speed grindings appeared to act as following the same mechanism as far as the productivity was concerned, but the rates of shives and fines formation did not follow such a pattern. The groundwood sheets showed lower tensile strength in high-speed grinding than in medium-speed grinding, while the light scattering coefficient was much lower for the high-speed grinding than for the medium-speed grinding. Because of its low productivity, the low-speed grinding does not seem to be useful, although high tensile strength and high light scattering of the sheets would plead for it. [ABSTRACT FROM AUTHOR]

[Display omitted] The presence of ions in a solution is anticipated to induce distinct effects on macromolecules. Consequently, the tuning of adsorption and mass transfer of lignin molecules can be achieved by incorporating ions with chaotropic or kosmotropic characteristics. This study examines the adsorption and mass transfer behavior of lignin molecules across model cellulose membranes in presence of ions from the Hofmeister series. Experimental investigations encompassed the use of diffusion cells to quantify lignin's mass transfer through the membranes, and quartz crystal microbalance with dissipation (QCM-D) monitoring was used for adsorption studies. Notably, at high ion concentrations, the mass transport rate of lignin was observed to be lower in the presence of highly hydrated (kosmotropic) sulfate ions, conforming to the Hofmeister series. Intriguingly, this relationship was not apparent at lower ion concentrations. Furthermore, QCM-D experiments indicated that lignin displayed higher adsorption onto the cellulose surface when exposed to less hydrated (chaotropic) nitrate anions. This behavior can be rationalized by considering the system's increased entropy gain, facilitated by the release of adsorbed ions and water molecules from the cellulose surface upon lignin adsorption. This study highlights the complexity of ion-specific effects on mass transfer and adsorption processes and their dependency on ion concentrations. [ABSTRACT FROM AUTHOR]

European paper mills are currently facing the question of whether recovered paper, their main raw material, will be available in sufficient quantities and an acceptable quality in the future. An alternative to recovered paper or wood fiber is the use of agricultural residues such as wheat straw. Sodium carbonate-based straw pulping processes have the advantage of not requiring recausticizing for chemical recovery, which reduces investment and operating costs. With the addition of oxygen, delignification can be significantly improved to provide pulps suitable for bleaching. This study compares the pulping of wheat straw using sodium carbonate, sodium carbonate + oxygen, and sodium carbonate + sodium hydroxide + oxygen. Pulping parameters such as temperature, retention time, and chemical charge were varied, and their influence on pulp properties was studied. The use of sodium carbonate alone produced pulps with high yields of up to 72% and comparably high burst and compressive strength. The addition of oxygen and small amounts of sodium hydroxide produced pulps with a high initial brightness of 42 %ISO and a low kappa number (18), still at high pulp yields of 62%. These pulps were two-stage bleached to achieve brightness levels of up to 73 %ISO. [ABSTRACT FROM AUTHOR]

Low-cost production of nanocellulose from diverse lignocellulosic feedstocks has become an important topic for developing sustainable nanomaterials. The available feedstocks include both woody and nonwoody plants, where the latter are relatively underutilized. Interestingly, the porous structure and low lignin content in most non-woody plants, such as agricultural residues and natural fibers, also makes them ideal sources for lower energy nanocellulose production using simpler methods than those required to process woody plants. To enhance the goal of circularity, this review first provides an overview of the nanocellulose conversion from cellulose and then comprehensively discusses the use of non-woody feedstocks for nanocellulose production. Specifically, the availability of suitable non-woody feedstocks and the use of low-cost processes for pulping and cellulose oxidation treatments, including alkaline, solvent pulping, and nitrogen-oxidation treatments, are discussed. The information in this review can lead to new opportunities to achieve greater sustainability in biobased economies. Additionally, demonstrations of nanocellulose-based water purification technologies using agricultural residues derived remediation materials are highlighted at the end of this review. [ABSTRACT FROM AUTHOR]

Background and Objectives: While the primary objective of cultivating of seed flax (Linum usititassimum L.) is to produce seeds and extract oil, the plant's significant quantities of long bast fibers also make it a favorable source for papermaking industries. The aims of this study were to assess the quantitative and qualitative characteristics of seed flax and analyze its pulping properties, while exploring the impact of planting distance on these identified characteristics. Materials and Methods: This study was conducted at the UPark farm of the University of Maine, USA, spanning from May to August 2015. The experiments followed a split-plot design within a randomized complete block layout. The primary factors consisted of four planting distances (9.0, 5.1, 2.2, and 4.4 cm), while the secondary factors included three harvest times (50, 75, and 100 days after planting). The distance between the planting rows was set at 4.25 cm, and each plot was comprised of five rows, each measuring 2 m in length. For each plot, the diameter and length of stems were measured for 30 samples extracted from the three middle rows at 50, 75, and 100 days after planting. Following the sample harvest, various plant components (core, stem bast, leaves, roots, and fruit capsules) were measured, and their respective weights and weight percentages per hectare were calculated in the laboratory. Additionally, fiber biometrics analyses were conducted on the stem bast and core. Pulping experiments were performed using the bast and the whole stem using two methods: SO2-ethanol-water (SEW) and soda. All statistical analyses were carried out utilizing the SPSS software, and the means were compared using the Duncan test at significance levels of 1% and 5%. Results: The results of the ANOVA indicated that the individual effects of different factors on the length and diameter of seed flax stems were significant at the 1% level, while their interaction was not significant. Increasing the planting distance led to higher yields of stem, root, leaf, and fruit capsules. Despite a decrease in the percentage of seed flax stem bast from 33% to 25.4% when the planting distance increased from 0.9 cm to 4.4 cm, the overall stem yield showed a significant increase. Notably, the longest bast and core fibers (4700 µm and 608 µm, respectively) were observed at a planting distance of 0.9 cm, while the shortest fibers (4080 µm and 510 µm, respectively) were at 4.4 cm. The pulping experiments conducted using the whole stem with soda and SEW methods demonstrated that the highest and lowest yields were 62.9% and 48.57%, respectively, achieved at cooking times of 30 and 90 minutes in the SEW process. The ANOVA results indicated that the independent effects of planting distance and stem components on the Kappa number of the resulting SEW pulps were significant at the 5% and 1% levels, respectively. The highest Kappa number (62.12) was associated with the pulp obtained from the core of seed flax planted at a distance of 4.4 cm, while the lowest (14.88) was associated with the bast of seed flax planted at a distance of 0.9 cm. The Duncan test revealed no significant difference in the Kappa values of the pulp obtained from the core of seed flax planted at distances of 0.9 and 4.4 cm. Conclusion: Increasing the planting distance of seed flax positively influences the yield of both bast and core of the stem. However, qualitatively, the length of bast and core fibers decreases, with the length of bast fibers consistently being approximately 8 times longer than that of core fibers. In terms of pulping, both the Kappa value and the yield of SEW pulp obtained from the bast and the core of the stem increases. [ABSTRACT FROM AUTHOR]

Cellulose nanocrystals (CNC) were prepared from delignified kenaf bast fiber by using alkaline pulping, based on soda anthraquinone, hydrogen peroxide bleaching, and acid hydrolysis treatment with H2SO4. The size and morphology of the fibers were characterized by scanning electron microscopy (SEM), and the isolated fiber from unbleached and bleached pulp had a diameter between 9 to 30 µm. Fourier transform infrared (FTIR) spectroscopy exhibited that the content of lignin decreased in the pulping process, and the lignin was almost completely removed during hydrogen peroxide bleaching. Moreover, fibers were characterized for crystallinity using X-ray diffraction (XRD). The fiber crystallinity gradually increased at each stage of the process (raw kenaf bast, unbleached pulp, bleached pulp, and acid hydrolysis). The fiber was characterized by atomic force microscopy (AFM), which showed that the isolated pulp nanofibers had diameters of approximately 30 nm. [ABSTRACT FROM AUTHOR]

Wood is an abundant and renewable feedstock for pulping and biorefining, but the aromatic polymer lignin greatly limits its efficient use. Sulis et al. recently reported a multiplex CRISPR editing strategy targeting multiple lignin biosynthetic genes to achieve combined lignin modifications, improve wood properties, and make pulping more sustainable. [ABSTRACT FROM AUTHOR]

A new method of recycling cooking with pulping wastewater was developed to save energy and reduce carbon dioxide emissions in a pulp mill, which used bio-fuel of eucalyptus instead of coal and oil, and reduced the steps of black liquor combustion and lime regeneration in the traditional pulp mill to reduce carbon dioxide emission. As results, the bio-fuel consumption and CO 2 emission are 2.04 × 104 MJ (1.2 tons of eucalyptus) and 2.2 tons for per ton of pulp. It reduces 28.23% of fuel energy consumption and 14.06% of CO 2 emission comparison with that by the traditional pulp mill. In addition, while using the generated lignin as part of bio-fuel, the product value-added is 765.88 RMB for per ton of pulp, being 23.72% lower than that of 1004.08 RMB by the traditional pulp mill. Therefore, this study demonstrates the advance and feasibility of using only bio-fuel for a new pulp mill with a new method of recycling cooking, and will promote the technological revolution of cleaner production in the pulp and paper industry. [ABSTRACT FROM AUTHOR]

Apple wood waste (AWW), mainly tree trucks, is collectible lignocellulosic biomass from orchard rotation. The biorefinery of AWW is challenging because of the hard and dense structure. In the present work, chemical composition determination and microstructure observation was performed for the first time on AWW. Alkali-preimpregnation-assisted soda cooking (APSC) was developed to separate cellulose a pulp and lignin from AWW. APSC attained pulp yield of 34.2% at 23% NaOH, showing a 13.2% improvement compared to conventional soda cooking (SC). Fiber length analysis showed APSC-AWW pulp consisted mainly of medium and short fibers, which means blending with long-fibered pulp to enhance the physical strength of pulp sheets. A blend of APSC-AWW pulp and long-fibered pulp in the proportion of 80:20 attained comparable physical strength to hardwood kraft pulp. ASPC-AWW lignin was separated from spent liquor by acidification and then purified by dialysis desalination. The purified ASPC-AWW lignin showed a weight-average molecular weight of 4462 g/mol, similar to softwood kraft lignin but more uniform. Structural analysis revealed that ASPC-AWW lignin was composed of a syringyl unit (S), guaiacyl unit(G), and p-hydroxyphenyl unit (H), and an S unit was dominant with an S/G/H ratio of 74.5:18.2:7.3. It is believed the utilization of fruit tree wood waste as the feedstock of biorefinery is attractive to countries without sufficient forestry resources. Furthermore, the developed APSC is based on conventional SC, which ensures the feasibility of an industrial application. [ABSTRACT FROM AUTHOR]

The biochemical sludge was mixed with coal-water slurry to prepare the slurry. The effect of the biochemical sludge on slurry performance and gasification performance was investigated through the analysis and research of the additive amount, slurry concentration, rheological properties, water separation rate and gasification simulation calculation. The results showed that the maximum addition amount of biochemical sludge is 10% under the condition of constant slurry concentration, and it was necessary to increase the amount of additives to maintain the slurry performance; the slurry with 10% biochemical sludge can be used for the gasification process to produce syngas, the total dry gas volume during gasification decreased by about 4.8%, the effective gas content decreased by about 1.2%,the specific oxygen consumption was basically unchanged, and the raw material consumption increased by about 6.6% . [ABSTRACT FROM AUTHOR]

Pineapple leaf fibers (PALF) were biopulped using Trametes versicolor, and the resulting biopulp was bleached with xylanase-enzymatic treatments. The biopulping was extensively described using determinations of fiber morphology, color, chemical composition, extractive content, and thermal stability using the structural characteristics determined by XRD and paper properties. The results showed that the chemical and enzymatic treatments shortened the fiber, almost to 50%, and the Kappa index decreased from 27 to 13. Cellulose and holocellulose contents increased from 65% to 74% and from 86% to 91%, respectively, but extractives, lignin (from 12% to 4%), pentosans (from 25% to 14%) and the crystallinity decreased from 58% to 67% in both chemical bleaching and further xylanase-enzymatic processing. Xylanase)enzymatic processing allowed us to obtain whiter (increased lightness color and decreased redness and yellowness tonality) and heavier paper, even though it presented decreased mechanical properties (decreased stress resistance, rupture length, tear resistance and index longitudinal tearing). The xylanase-enzymatic treatment with the best pulping and paper proper)ties is when the biopulp is treated with a xylanase enzyme concentration of 0.04% (w/w). [ABSTRACT FROM AUTHOR]

The article provides data on radioisotope device, including a radioisotope level meter – a radioisotope indicator of the level of petroleum coke and a radioisotope density meter. The article describes the methods of calibration of radioisotope density meter Gammapilot (Endress+Hauser AG, Switzerland). An ionizing radiation source of Cesium-137 GCS7.021.1 type with an activity of 3.06 × 109 Bq (82.7 mCi) was used to complete the radioisotope densitometer, and its tightness was checked using the immersion method with 8% ortophosphoric acid as the immersion liquid. To calibrate radioisotope densitometers, simulator stands and liquid simulators of various densities were made based on a mixture of tribromomethane and ethyl alcohol solutions. Radioisotope density meters were calibrated for low pulp emulsion density, medium pulp emulsion density, and high pulp emulsion density. In calibrated radioisotope density meters, upon reaching the lower limit of the pulp density in the detection unit, an output electrical signal appears at the "0–5 mA" connector, and when the upper limit of the pulp density is reached, an output electrical signal appears at the "4–20 mA" connector. [ABSTRACT FROM AUTHOR]

The feasibility of the pulping technology depends on the efficiency of by-products and solvent recovery. In this regard, the development of an environmentally friendly peracetic method of delignification should be accompanied by the development of an effective method of lignin disposal. Usually, delignification methods are characterized without a detailed study of the by-products. Herein, let's describe the structural and chemical characteristics of lignin, as well as its sorption properties. Pulping liquors after peracetic delignification of rapeseed straw were used in this work. The application of sodium tungstate and sodium molybdate as catalysts gave a significant effect on the dissolution of lignin during pulping. The composition, structure and functional groups of lignins were investigated. Application of catalysts in organosolv pulping resulted in small amounts of carbohydrates in lignins if compare to lignins after non-catalytic pulping. As catalysts, Na2WO4 and Na2MoO4 exhibited no obvious differences in carbohydrate contents and in molecular weights of organosolv lignin (Mw = 4910–5640 g/mol, Mn = 2350–2500 g/mol). The obtained lignin was successfully used for Methylene Blue adsorption due to high content of functional groups (R-OH = 1.72 mmol/g, Ph-OH = 5.72 mmol/g, R-COOH = 0.88 mmol/g) despite the poorly developed porous structure (11.03 ± 0.35 m2/g). Lignin has potential applicability as a biosorbent for wastewater treatment to solve environmental problems of water pollution. [ABSTRACT FROM AUTHOR]

Research by the paper industry into new materials to expand the raw material base for pulp is on the ascendancy due to growing demand for pulp and paper products. This study assessed the anatomical, chemical, and pulping characteristics of four varieties of Cocos nucifera husk to ascertain their suitability as raw material for pulp and paper production. The measured and calculated chemical (Klason Lignin, 1% NaOH solubility and Holocellulose contents) and anatomical (Fiber dimensions, Runkel Ratio, Slenderness Ratio, Flexibility Coefficient, Coefficient of Rigidity, Luce's Shape Factor and Solids Factor) properties of the Cocos nucifera husks mostly did not meet the standard requirements for a good pulp and paper material. However, the Local Tall Yellow variety of the Cocos nucifera husk was favorable in terms of Runkel Ratio, Slenderness Ratio, Flexibility Coefficient, and Coefficient of Rigidity and can be considered for the production of pulp for writing and printing papers. In spite of the limitations of the other three varieties for making quality paper, they could be used for fiber plate, rigid cardboard, and cardboard production. [ABSTRACT FROM AUTHOR]

The spleen is a large and highly vascularized secondary lymphatic organ. Spleen injuries are among the most frequent trauma‐related injuries in the abdominal region. The aims of the study were to assess the volume fractions of the main splenic tissue components (red pulp, white pulp, trabeculae and reticular fibres) and to determine the severity of splenic injury due to the experimental impact test. Porcine spleens (n = 17) were compressed by 6.22 kg wooden plate using a drop tower technique from three impact heights (50, 100 and 150 mm corresponding to velocities 0.79, 1.24 and 1.58 m/s). The pressure was measured via catheters placed in the splenic vein. The impact velocity was measured using lasers. The severity of induced injuries was analysed on the macroscopic level. The volume fractions of splenic components were assessed microscopically using stereology. The volume fraction of the red pulp was 76.4%, white pulp 21.3% and trabeculae 2.7% respectively. All impact tests, even with the low impact velocities, led to injuries that occurred mostly in the dorsal extremity of the spleen, and were accompanied by bleeding, capsule rupture and parenchyma crushing. Higher impact height (impact velocity and impact energy) caused more severe injury. Porcine spleen had the same volume fraction of tissue components as human spleen, therefore we concluded that the porcine spleen was a suitable organ model for mechanical experiments. Based on our observations, regions around hilum and the diaphragmatic surface of the dorsal extremity, that contained fissures and notches, were the most prone to injury and required considerable attention during splenic examination after injury. The primary mechanical data are now available for the researchers focused on the splenic trauma modelling. [ABSTRACT FROM AUTHOR]

In this study, the sulphur oxide anions profile at all stages of the Mg acid sulphite pulping process was evaluated by Ion Chromatography (IC). The concentration of bisulphite anions decreased almost two-third along the cooking, while the sulphate concentration increased progressively. Of the bisulphite consumed, only a third was converted to sulfates. Unexpectedly, the maximum thiosulphate concentration was found in the pulping acid filling step, being further decreased along the cooking. The chloride ions rise progressively during the cooking being extracted essentially from the wood, although a noticeable part of the phosphate anions belongs to pulping reagents and inlet water. The low molecular weight fraction of lignosulphonates (LS) appeared in the cooking liquor in the residual delignification step and, together with xylonic acid, contributed to an overestimation of the fluoride concentration determined by the IC due to the same retention time in the chromatographic column during the analysis. [ABSTRACT FROM AUTHOR]

A crucial step in the chemical delignification of wood is the transport of lignin fragments into free liquor; this step is believed to be the rate-limiting step. This study has investigated the diffusion of kraft lignin molecules through model cellulose membranes of various pore sizes (1–200 nm) by diffusion cells, where the lignin molecules diffuse from donor to acceptor cells through a membrane, where diffusion rate increases by pore size. UV–vis spectra of the donor solutions showed greater absorbance at higher wavelengths (~450 nm), which was probably induced by scattering due to presence of large molecules/clusters, while acceptor samples passed through small pore membranes did not. The UV–vis spectra of acceptor solutions show a characteristic peak at around 350 nm, which corresponds to ionized conjugated molecules: indicating that a chemical fractionation has occurred. Size exclusion chromatography (SEC) showed a difference in the molecular weight (Mw) distribution between lignin from the donor and acceptor chambers. The results show that small pore sizes enable the diffusion of small individual molecules and hinder the transport of large lignin molecules or possible lignin clusters. This study provides more detail in understanding the mass transfer events of pulping processes. [ABSTRACT FROM AUTHOR]

Cannabis indica stems were hydrolyzed with subcritical water at various temperatures, reaction times, and feed concentrations. The highest total yield of reducing sugars of 16.4 wt % was obtained at 190 °C in 37.5 min with a feed concentration of 3.5 wt %. Solid residues from the optimized process were treated with 0.5 M NaOH (pulping) and 0.5–3 % H2O2 (bleaching) to isolate cellulose fibers. The maximum yield of cellulose was 34.8 wt % with lowest lignin content of 0.5 wt %. With the removal of hemicellulose and lignin through the integrated hydrothermal processes, the crystallinity index and thermal stability of the cellulose fibers increased. [ABSTRACT FROM AUTHOR]

Nanofibrillated cellulose (NFC) has generated significant interest due to growing concerns about low carbon emission, environmental issues, and the guaranteed outstanding performance of applied products. Because of this trend, the importance of NFC production from an industrial angle has also been emphasized. In this study, ground pulps (at -300 μm clearance, 40 passes) were homogenized by using a pilot-scale microfluidizer (at 1,500 bar, up to 5 passes) to produce the NFC, and its characteristics were investigated. Scanning electron microscope (SEM) images showed that the size and distribution of the NFC particles gradually decreased by up to three passes on account of the microfluidizer treatment and remained constant after that mechanical pass number. The viscoelastic properties (dynamic moduli) and viscosity of the NFC suspension steadily increased with three passes of the treatment, and the same trends as in the SEM images were observed after these passes. These results demonstrated that the NFC fluid behavior inside the equipment depends on the morphological properties of the manufactured NFC particles. Additionally, a good agreement between the morphological and rheological results implied that rheological analysis can be a reasonable approach to predicting the quality (size and distribution) of manufactured NFC particles. [ABSTRACT FROM AUTHOR]

This study deals with a new methodology for the production of carboxymethyl cellulose (CMC) from olive pruning residues, agricultural by-products. Cellulose was extracted by the soda-anthraquinone pulping process, and the pulp bleaching was performed using totally chlorine free (TCF) bleaching. Then, CMC microwave-assisted synthesis was performed in a homogeneous media, using DMA/LiCl as a cellulose solvent. A Box-Behnken design was applied in order to evaluate which parameters of the carboxymethylation process (viz. reaction time, reaction temperature, and amount of monochloroacetic acid) affect the degree of substitution and the yield of the synthesis reaction of this cellulose derivative. Optimized conditions to yield CMC were determined based on the desirability function approach. The prepared materials under synthesis using the optimal conditions were characterized using several analytical tools, i.e., FTIR, TGA, DSC and SEM. This cellulose derivative was successfully fabricated by a fast and efficient microwave-assisted method and thus would provide many opportunities for diverse applications. [ABSTRACT FROM AUTHOR]

Sustainable composite foams based on rice starch and cellulosic long fibers were successfully fabricated using microwave irradiation. They were presented as a promising method to recycle some of the textile industry waste. A deep study of the processability and functionality of the composites revealed the performance improvement of starch with the addition of long cellulosic fibers, especially with 6 wt% of Arbocel®, in terms of foamability, water, and mechanical resistance features. Moreover, sodium bicarbonate, which acted as a blowing and pulping agent, led to a lower density and better fiber distribution that resulted in an improvement of the foams' functionalities. The range of the study is new in the domain of long fiber foam composites in terms of the foaming capability, and mechanical, thermal, and water resistance properties. Furthermore, all foams showed excellent biodegradability properties against a fungus commonly found in the environment; for example, values around 60 % weight loss after 33 days. Finally, the assessment of the CO 2 emission during the process underlines the environmental benefits of the method employed. [Display omitted] [ABSTRACT FROM AUTHOR]

The volumetric change that occurs in the pulp space over time represents a critical measure when it comes to determining the secondary outcomes of regenerative endodontic procedures (REPs). However, to date, only a few studies have investigated the accuracy of the available domain-specialized medical imaging tools with regard to three-dimensional (3D) volumetric assessment. This study sought to compare the accuracy of two different artificial intelligence-based medical imaging programs namely OsiriX MD (v 9.0, Pixmeo SARL, Bernex Switzerland, https://www.osirix-viewer.com) and 3D Slicer (http://www.slicer.org), in terms of estimating the volume of the pulp space following a REP. An Invitro assessment was performed to check the reliability and sensitivity of the two medical imaging programs in use. For the subsequent clinical application, pre- and post-procedure cone beam computed tomography scans of 35 immature permanent teeth with necrotic pulp and periradicular pathosis that had been treated with a cell-homing concept-based REP were processed using the two biomedical DICOM software programs (OsiriX MD and 3D Slicer). The volumetric changes in the teeth's pulp spaces were assessed using semi-automated techniques in both programs. The data were statistically analyzed using t-tests and paired t-tests (P = 0.05). The pulp space volumes measured using both programs revealed a statistically significant decrease in the pulp space volume following the REP (P < 0.05), with no significant difference being found between the two programs (P > 0.05). The mean decreases in the pulp space volumes measured using OsiriX MD and 3D Slicer were 25.06% ± 19.45% and 26.10% ± 18.90%, respectively. The open-source software (3D Slicer) was found to be as accurate as the commercially available software with regard to the volumetric assessment of the post-REP pulp space. This study was the first to demonstrate the step-by-step application of 3D Slicer, a user-friendly and easily accessible open-source multiplatform software program for the segmentation and volume estimation of the pulp spaces of teeth treated with REPs. [ABSTRACT FROM AUTHOR]

In order to study the anti-blast performance of flexible fabrics, the dynamic response and failure behavior of aramid fabric under blast impact were analyzed with the numerical simulation method. Mechanical tests of aramid fabric H I 000D-AP220 were carried out, and the constitutive model for woven fabric and the explosive numerical analysis model were established. The dynamic responses and failure modes of the fabrics under different loads were obtained by the analysis of fabrics with different thicknesses and different stacking angles. The results show that, there are 2 typical failure modes of fabrics under the explosive impact: the failure of the central hole and the tensile tear at the boundary, with obvious folds in the width direction of the fabric. The front and back layers absorb more energy than the middle ones. Better anti-explosion ability can be achieved through adjustment of the fabric stacking angle. [ABSTRACT FROM AUTHOR]

Mechanical pulp for printing paper can be produced with a process that involve much less equipment and that require much lower specific energy compared to conventional processes. Even though common evaluation methods, e.g. handsheet testing, have shown that the pulp quality is similar for the simplified and the conventional processes, it is not known how fibre properties, at the microscopic level, is developed with the simplified process. In this mill scale study, the fibre properties attained with an "intensified" mechanical pulping process, consisting of single stage high consistency double disc refining followed by two stage low consistency refining and no reject treatment was investigated. The simplified process was compared to a process with a reject system. The simplified process rendered fibres with higher degree of fibrillation, higher share of axial splits, lower fibre wall thickness but slightly lower length than the conventional process. The fibrillar fines size distribution of the two processes was different. The conventional process generated more of small fibrillar fines which probably explains the higher tensile index at given density for that process. The results show that it is possible to simplify the production process for mechanical pulp and reduce the specific energy with over 700 kWh/adt. [ABSTRACT FROM AUTHOR]

Acacia, an exotic fast-growing tree species was introduced into Southeast Asian countries on degraded soils. In Bangladesh, China, India, Vietnam, Indonesia plantations of Acacia were established for pulpwood production with people's participation. This paper reviews the current knowledge of the physical, chemical and morphological characteristics of A. auriculiformis and its pulping potential. The wood density, chemical and morphological properties of A. auriculiformis impacted positively for pulpwood selection in many countries. A. auriculiformis planted in a social forestry programme in Bangladesh and other countries showed almost similar characteristics to A. auriculiformis grown in different parts of the world. It is a promising species for pulping in Bangladesh and other Southeast Asian countries, at the same time poor people can improve their livelihood through participation in social forestry programme by planting this species. [ABSTRACT FROM AUTHOR]

Based on the loss model of pulp pump set up in the I part of this research, an efficient designing method is proposed by taking account of the influences of head reduction by small blade number, leakage loss via tip clearance, and erosion-corrosion wears in pumps separately. Further, a two-stage optimal designing approach was proposed to tackle the oversized design. The pump designing was performed by coupling with a CFD-based optimization procedure. An efficiency increase of near 10 % was achieved on the pump model validated in laboratory. It was proved that performance could be improved by increasing the impeller blade width and enlarging the impeller blade outlet angle. It was further shown that the erosion-corrosion wear in pulp pump was relatively lighter when compared to particle-impingement wear in slurry and sewage pump. Adoption of composite material showed potential in energy-saving in the pumping system. [ABSTRACT FROM AUTHOR]

With growing demand of paper products, the electric consumption in pulp and paper industry is increasing globally where a share of 30 % is attributed to the pulp pumping system. The efficient designing and running of pumping system are critical for energy efficiency. The incomplete information on pulp flows and the oversized designs are the major causes of low efficiency. In the first part of this research, the fiber level models and rheological properties covering a series of unit applications are examined. A loss model of pulp pump is set up by considering different factors influencing pumping performance. The efficiency improvement opportunities in pulp pumping are systematically investigated. The drag-reducing feature at low consistency pulp pumping is highlighted which will be further applied in energy optimized sizing and dimensioning of a pulp pump in the second part of this research. [ABSTRACT FROM AUTHOR]

High yield pulps (HYP), manufactured in mechanical and chemimechanical pulping processes, are mainly used in graphic papers and paper grades where a high bulk is preferable, like in paperboards. Moreover, packaging papers with very high demands on both dry and wet strength could be manufactured from HYP in a near future. Preferred bonds between fibre components (long fibres, shortened fibres and fines) in the various paper grades are quite different. In the review, plausible effects of mechanical interlocking, intermolecular interactions ("physical bonding"), hydrogen bonds, intermixing of polymers, additives and possible specific interactions in the formation of strong bonds in sheet structures from HYP are discussed. A required condition for high bond strength in sheets from HYP furnishes is that fibre components are forced into sufficiently close contact. This is to a great extent impeded if the fibre walls are too stiff. Consequently, the current review focuses on both how fibre fractions should preferably be developed for different end uses and how suitable bonds might be achieved in different paper grades. The ideal type of bonds is certainly different depending on the demands on the final paper quality. [ABSTRACT FROM AUTHOR]

The goal of this paper is to model the pulp properties fiber length, shives width and freeness. This will be done utilizing specific energy, flat zone inlet consistency and the internal variables, consistencies and fiber residence times estimated from refining zone soft sensors. The models are designed using more than 3600 hours of data from a RGP82CD refiner. The pulp properties are sampled using a measurement device positioned after the latency chest. Such measurements are noisy and irregularly sampled which opens for a number of challenges to overcome in modeling procedures. In this paper it is shown that the models for shives width and fiber length are capable of predicting most of the major dynamics. However, for freeness no reliable linear models can be derived. When estimating fiber length, the specific energy together with flat zone inlet consistency, fiber residence times and the consistency in the conical zone were the dominant inputs. For shives width it was found that a similar set of inputs resulted in the best models, except that the consistencies during normal process conditions did not significantly influence shives width. Furthermore, fiber residence times were shown to have considerably more pronounced impact on fiber length compared with shives width estimates.

One way to obtain high quality pulp production is to improve selectivity delignification of step, maximize yield. Brown pulp yield and chemical composition were studied, with variation of temperature and effective alkali in Kraft cooking. Considering that these variables directly affect lignin removal rate and final product quality. Industrial wood chips from Eucalyptus grandis x Eucalyptus urophylla hybrids were used in this study. The cooking was performed to obtain pulps with kappa number 13, 15 and 17 for temperatures 155 °C, 160 °C and 165 °C, using the same Factor H (695). Yields were analyzed according to: total yield, rejects content and screened pulp yield. Klason lignin content, wood and pulp sugars, levels of hexenuronic acids in pulp were also determined. Results indicate that lower cooking temperatures are beneficial in relation to cooking performance, selectivity and preservation of xylans. With a screened pulp yield of 57.1 % for KN 17 at the lowest temperature 155 ºC and 55.3 % at the same KN at 165 ºC. The lowest screened pulp yield obtained, 51 %, was for KN 13 at 165 ºC, with 54.1 % with the same KN at 155 ºC. Evidencing a decreasing linear trend of screened pulp yield with temperature increase and kappa number reduction. [ABSTRACT FROM AUTHOR]

In the last years, renewable energies have been proposed as a solution to mitigate climate change. In this sense, biomass has become a more popular alternative than other sources of renewable energy, such as solar energy and wind power. As its main advantage, biomass is obtained from organic material, which makes it consistent throughout the year. Studies on biomass as a source of energy are usually conducted at a pilot scale to determine its energetic potential. However, there is less emphasis on studying the logistic operations and key variables that enable the feasibility of biomass as a source of energy at an industrial scale. To address this gap, we study the potential of coffee pulp as a source of biomass, and consequently, as a source of energy. To this end, we use the System Dynamics methodology. First, we developed a simulation model where the results indicate that one ton of coffee pulp can produce 180 m3 of biogas, which in turn can generate 0.41 MW of net electricity. Then, we performed a 20-year sensitivity analysis to identify the key variables ensuring electricity generation from coffee pulp which include: harvested area (hectares), cherry coffee yield (ton/ha), and efficient usage of coffee pulp. • Feasibility of using coffee pulp biomass to generate renewable energy was evaluated. • It is necessary to use industrial coffee waste to generate electricity. • Key variables are: harvested area, yield per hectare and efficient use of pulp. • The energy contribution of coffee pulp to the Mexican energy matrix was assessed. • System dynamics is a powerful tool to assess the energy potential of biomass. [ABSTRACT FROM AUTHOR]

Lipases (triacylglycerol acylhydrolase, E.C. 3.1.1.3 are a class of enzymes that catalyze several important reactions viz. hydrolysis, aminolysis, alcoholysis, and esterification. Hence, switching to lipase production using low-cost cultivation media through solid-state fermentation (SSF) of agro-industry biomass may prove beneficial in lowering the production cost. In this study, mold isolated from fermented soybean was selected for producing lipase through SSF using coconut pulp as the substrate. Results revealed that a 4-day incubation was optimum for the SSF of coconut pulp to produce the highest lipase activity and protein content, which are 12.0 U ml-1 and 0.75 mg ml-1, respectively. Specific activity of the lipase reached its maximum at 15.9 U mg-1 with incubation at 35°C and pH 7.5. Moreover, it catalyzed the hydrolysis of olive oil with an activation energy of 43.46 kJ mol-1. Results demonstrated that the strategy adopted in this study to produce lipase by SSF of coconut pulp appeared to be a promising approach. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the biological activities of the ultrasound‐assisted extracts obtained from pulp and seed of jujube (Ziziphus jujuba) fruits. To reach this purpose, total phenolic content (TPC), total flavonoid content (TFC), total pro‐anthocyanin, DPPH radical scavenging activity, rancimat test, as well as antimicrobial activity and cytotoxicity test of both jujube pulp and seed extracts were evaluated. Total phenolic content (TPC), total flavonoid content (TFC), and total pro‐anthocyanin in pulp extract were higher than those obtained from seed extract. In addition, DPPH radical scavenging activity of pulp extract (IC50 = 53.97 µg/ml) was higher than that of seed extract (IC50 = 88.68 µg/ml). Furthermore, the highest antimicrobial activity was observed against Escherichia coli and Staphylococcus aureus (MIC = 20 mg/ml) for both seed and pulp extracts. In vitro cytotoxicity evaluation on seven cell lines revealed that pulp and seed extracts of jujube had no cytotoxic activity. The present results suggested the promising antioxidant properties of jujube, which can be used in the fabrication of functional bioactive ingredients for different purposes. [ABSTRACT FROM AUTHOR]

• LA production from date pulp waste by indigenous microbiota was investigated. • Enzymatic hydrolysis of the date pulp waste gave high yields of LA. • Higher LA productivity (3.56 g/L.d), and yield (0.07 g/g-TS) were achieved. • ANN model was developed for optimization and to the prediction of LA production. • ANN model predicted optimal conditions well and showed good agreement between data. Biowaste valorization into lactic acid (LA) by treatment with indigenous microbiota has recently gained considerable attention. LA production from date pulp waste provides an opportunity for resource recovery, reduces environmental issues, and possibly turns biomass into wealth. This study aimed to compare the performance of batch and cyclic fermentation processes in LA production with and without enzymatic pretreatment. The fermentation studies were conducted in the absence of an external inoculum source (relying on indigenous microbiota) and without the addition of nutrients. The highest LA volumetric productivity (3.56 g/liter/day), yield (0.07 g/g-TS), and concentration (21.66 g/L) were attained with enzymatic pretreated date pulp in the cyclic-mode fermentation at the optimized conditions. The productivity rate of LA was enhanced in the cyclic-mode as compared to the batch process. Enzymatic pretreatment increased the digestibility of cellulose that led to higher LA yield. An Artificial Neural Network model was developed to optimize the process parameters and to predict the LA concentration from date pulp waste in both fermentation processes. The main advantage of the ANN approach is the ability to perform quick predictions without resource-consuming experiments. The model predicted optimal conditions well and demonstrated good agreement between experimental and predicted data. [ABSTRACT FROM AUTHOR]

The Bayesian approach is being a fundamental tool in forensic and legal field where inferences and decisions are made. In this study, a full Bayesian calibration model was developed to make probabilistic inferences about age estimation in a reference sample of 891 periapical X-rays of upper and lower canines. These teeth belonged to both deceased and living adult subjects, aged between 20 and 86 years, coming from five different countries (Turkey, Italy, Portugal, Japan and Mexico). For this purpose, the narrowing of pulp chamber due to the apposition of secondary dentine was analysed by means of the pulp/tooth area ratio. To determine the agreement of the method, intra- and inter-observer differences for measuring process were calculated by means of the intraclass correlation coefficient (ICC) analysis. Observer error tests showed excellent agreement between observers and between repeated assessments. According to the results of the ANCOVA, neither nationality nor sex was associated to the secondary dentine apposition while it is associated with individual's age. The results of the present study indicated that the concept of probability is intrinsically linked to the assessment of age in a forensic context, and the Bayesian approach could be considered a robust tool to overtake the bias generated by traditional regression models, thus helping the decision-making process in a legal framework. [ABSTRACT FROM AUTHOR]

The properties of gold nanoparticles, such as conductivity, half-life, catalytic nature, improved solubility efficiency, chemical stability, and its mechanism in binding with bacterial cell wall to induce cell death, have increased its medicinal applications. This study investigated the antibacterial property of gold nanoparticles (AuNPs) synthesized from Garcinia kola pulp extract. The ripe fruits of Garcinia kola were obtained, and the pulps were removed, air dried, pulverized, extracted, and mixed with gold chloride solution following standard procedure. The synthesized AuNPs were characterized using ultraviolet visible spectrophotometer (UV-visible), Fourier transform infrared (FTIR) spectrophotometer, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and energy-dispersive X-ray (EDX). The antibacterial examination was carried out on four clinical isolate bacteria using agar diffusion technique. The UV-visible analysis confirmed the formation of stable AuNPs at pH 7 in the wavelength region of 564 nm. The FTIR analysis confirmed that the secondary metabolites with –OH functional groups serve as the reducing agent for the synthesis of AuNPs. The morphological assessment of the synthesized AuNPs revealed spherical-shaped particles. The zones of inhibition of the synthesized AuNPs against test bacteria ranges from 3 to 13 mm while that of the control was in the range of 14 to 22 mm. This study provided an environmentally friendly approach in the synthesis of AuNPs from Garcinia kola pulps and also ascertained the medicinal application of the synthesized AuNPs as an antibacterial agent. [ABSTRACT FROM AUTHOR]

In Brazil, orally acquired T. cruzi infection has become the most relevant transmission mechanisms from public health perspective. Around 70% of new Chagas disease cases have been associated with consumption of contaminated food or beverages. Açai (Euterpe oleracea and Euterpe precatoria) is currently one of the most commercialized Amazonian fruits in the Brazilian and international markets. Therefore, it has become important to incorporate in the production process some procedures to measure out effective hygiene and product quality control required by global market. Molecular methods have been developed for rapid detection and quantification of T. cruzi DNA in several biological samples, including food matrices, for epidemiological investigation of Chagas disease and food quality control. However, a high-performance molecular methodology since DNA extraction until detection and quantification of T. cruzi DNA in açai berry pulp is still needed. Herein, a simple DNA extraction methodology was standardized from the supernatant of açai berry pulp stabilized in a 6M Guanidine-HCl/0.2M EDTA buffer. In addition, a multiplex real time qPCR assay, targeting T. cruzi DNA and an Exogenous Internal Positive Control was developed and validated, using reference from all T. cruzi DTUs and commercial samples of açai pulp, from an endemic municipality with previous history of oral Chagas disease outbreak. Thus, a high-sensitivity qPCR assay, that could detect up to 0.01 parasite equivalents/mL in açai, was reached. As of the 45 commercial samples analyzed, 9 (20%) were positive for T. cruzi. This high-sensitive, fast, and easy-to-use molecular assay is compatible with most of the laboratories involved in the investigations of oral Chagas disease outbreaks, representing an important tool to the epidemiology, control, and surveillance of Chagas disease. [ABSTRACT FROM AUTHOR]

This study involves the debittering of Citrus reticulata (kinnow) pulp residue and its value addition through incorporation for the preparation of vermicelli. The optimization of debittering has been monitored through conversion of naringin (bitterness causing compound) to naringenin (nonbitter compound) through enzymatic method. The enzyme (naringinase) concentration has been varied from 0.5 to 2.5 U/mg with temperature range of 25–65°C at pH 4.5 with incubation period of 2–6 hr. The maximum reduction (~66.19%) naringin was observed in the kinnow pulp residue, with increase in the naringenin concentration (nonbitter) of 52.38% under optimized conditions, that is, enzyme concentration (1 U/mg), temperature (50°C), and treatment time (4 hr) at natural pH (4.5). The debittered kinnow pulp residue was characterized for compositional analysis and morphological studies using SEM and FTIR. The obtained debittered kinnow pulp residue was further successfully utilized in the preparation of nutrient and antioxidant‐rich vermicelli. Practical applications: Food waste has been generated in abundance by fruits processing industries which are rich in mineral, antioxidants, and polyphenols. The bitterness in citrus waste (kinnow pulp, peel, and seeds), has posed a major issue for their utilization in different food products due to the problem of consumer acceptability. In present investigation, reduction in the content of naringin below the threshold limit resulted in debittering of kinnow pulp residue. Furthermore, this debittered pulp residue has been explored for its utilization for the preparation of antioxidant rich vermicelli. Results of this work depicted that such technology can be used for debittering of kinnow industry by‐products and can be subsequently utilized by the food industry in the preparation of antioxidant rich food products. This process is not only an effective utilization of agro‐industrial by‐products/wastes but also solution for environmental waste caused by kinnow juice industry. [ABSTRACT FROM AUTHOR]

The current work had two objectives: to compare the total phenolic content (TPC) and antioxidant activity via two different extraction methods ultrasound‐assisted extraction (UAE) and conventional orbital shaker (COS) extraction. Second, parameters (solvent concentration, acidity, and sample‐to‐solvent ratio) influence the extraction of phenolic compounds. For each respective solvent, the sample‐to‐solvent ratio compared were 1:5, 1:10, and 1:20. The TPC of the pulp was extracted most effectively by UAE (38.69 mg). Total mean of extraction yield across all parameters showed that UAE (561.7 mg) was statistically more effective in DPPH radical scavenging activity than the COS extraction (499.8 mg). However, the COS results from FRAP and ABTS yielded higher antioxidant activity. For all the tested assays, it was observed that the absolute methanol solvent and solvent‐to‐sample ratio of 1:20 were the most effective for extracting bioactive compounds from watermelon while solvent acidity had negligible effect. Novelty Impact Statement: Current work demonstrated how individual extraction characteristics (concentration, acidity, sample‐to‐solvent ratio, and method used for extraction) of watermelon "New Dragon A‐117" variety is located in the phenolics and antioxidant characteristic map. Thus, providing information that can practically assist future product developers for their product formulation as a nutraceutical in a more sustainable and environment friendly manner. [ABSTRACT FROM AUTHOR]

Background: Unresolved inflammation and tissue destruction are considered to underlie the failure of dental pulp repair. As key mediators of the injury response, dental pulp stem cells (DPSCs) play a critical role in pulp tissue repair and regeneration. Resolvin E1 (RvE1), a major dietary omega-3 polyunsaturated fatty-acid metabolite, is effective in resolving inflammation and activating wound healing. However, whether RvE1 facilitates injured pulp-tissue repair and regeneration through timely resolution of inflammation and rapid mobilization of DPSCs is unknown. Therefore, we established a pulp injury model and investigated the effects of RvE1 on DPSC-mediated inflammation resolution and injured pulp repair. Methods: A pulp injury model was established using 8-week-old Sprague-Dawley rats. Animals were sacrificed on days 1, 3, 7, 14, 21, and 28 after pulp capping with a collagen sponge immersed in PBS with RvE1 or PBS. Hematoxylin-eosin and Masson's trichrome staining, immunohistochemistry, and immunohistofluorescence were used to evaluate the prohealing properties of RvE1. hDPSCs were incubated with lipopolysaccharide (LPS) to induce an inflammatory response, and the expression of inflammatory factors after RvE1 application was measured. Effects of RvE1 on hDPSC proliferation, chemotaxis, and odontogenic differentiation were evaluated by CCK-8 assay, transwell assay, alkaline phosphatase (ALP) staining, alizarin red staining, and quantitative PCR, and possible signaling pathways were explored using western blotting. Results: In vivo, RvE1 reduced the necrosis rate of damaged pulp and preserved more vital pulps, and promoted injured pulp repair and reparative dentin formation. Further, it enhanced dentin matrix protein 1 and dentin sialoprotein expression and accelerated pulp inflammation resolution by suppressing TNF-α and IL-1β expression. RvE1 enhanced the recruitment of CD146+ and CD105+ DPSCs to the damaged molar pulp mesenchyme. Isolated primary cells exhibited the mesenchymal stem cell immunophenotype and differentiation. RvE1 promoted hDPSC proliferation and chemotaxis. RvE1 significantly attenuated pro-inflammatory cytokine (TNF-α, IL-1β, and IL-6) release and enhanced ALP activity, nodule mineralization, and especially, expression of the odontogenesis-related genes DMP1, DSPP, and BSP in LPS-stimulated DPSCs. RvE1 regulated AKT, ERK, and rS6 phosphorylation in LPS-stimulated DPSCs. Conclusions: RvE1 promotes pulp inflammation resolution and dentin regeneration and positively influences the proliferation, chemotaxis, and differentiation of LPS-stimulated hDPSCs. This response is, at least partially, dependent on AKT, ERK, and rS6-associated signaling in the inflammatory microenvironment. RvE1 has promising application potential in regenerative endodontics. [ABSTRACT FROM AUTHOR]

Xylanases are widely used enzymes in the food, textile, and paper industries. Most efficient xylanases have been identified from lignocellulose-degrading microbiota, such as the microbiota of the cow rumen and the termite hindgut. Xylanase genes from efficient pulp and paper wastewater treatment (PPWT) microbiota have been previously recovered by metagenomics, assigning most of the xylanase genes to the GH10 family. In this study, a total of 40 GH10 family xylanase genes derived from a certain PPWT microbiota were cloned and expressed in Escherichia coli BL21 (DE3). Among these xylanase genes, 14 showed xylanase activity on beechwood substrate. Two of these, PW-xyl9 and PW-xyl37, showed high activities, and were purified to evaluate their xylanase properties. Values of optimal pH and temperature for PW-xyl9 were pH 7 and 60 ℃, respectively, while those for PW-xyl37 were pH 7 and 55 ℃, respectively; their specific xylanase activities under optimal conditions were 470.1 U/mg protein and 113.7 U/mg protein, respectively. Furthermore, the Km values of PW-xyl9 and PW-xyl37 were determined as 8.02 and 18.8 g/L, respectively. The characterization of these two xylanases paves the way for potential application in future pulp and paper production and other industries, indicating that PPWT microbiota has been an undiscovered reservoir of efficient lignocellulase genes. This study demonstrates that a metagenomic approach has the potential to screen efficient xylanases of uncultured microorganisms from lignocellulose-degrading microbiota. In a similar way, other efficient lignocellulase genes might be identified from PPWT treatment microbiota in the future. [ABSTRACT FROM AUTHOR]

• Fermentations with SSL resulted in the upregulation of pepck and mdh that participate in the reductive TCA cycle. • Fumarate reductase that participates in oxidative phosphorylation and TCA cycle was significantly upregulated in SSL fermentations compared to pure substrates. • SSL and xylose resulted in similar and significant downregulation of ATP synthase compared to glucose. The fermentative production of biobased chemicals and polymers using crude lignocellulose hydrolysates is challenging due to the presence of various inhibitory compounds and multiple sugars. This study evaluates the metabolic response of Actinobacillus succinogenes for the production of succinic acid using spent sulphite liquor (SSL) as feedstock derived from industrial acidic sulphite pulping of Eucalyptus globulus hardwood. A transcriptomic approach led to significant insights on gene regulation of the major metabolic pathways (glycolysis, pentose phosphate pathway, TCA cycle, pyruvate metabolism and oxidative phosphorylation) in batch cultures carried out on SSL and compared with glucose and xylose. Significantly overexpressed genes in SSL compared to glucose and xylose were fructose biphosphate aldolase (> 1.18-fold change) in the catabolism, phosphoenolpyruvate carboxykinase (> 1.59-fold change) and malate dehydrogenase (> 1.49-fold change) in the TCA cycle, citrate lyase (> 1.7-fold change), dihydrolipoamide dehydrogenase (> 0.88-fold change), pyruvate dehydrogenase E2 (> 1.63-fold change) and pyruvate formate lyase (> 0.61-fold change), involved in acetyl-CoA pathways. Finally, C4 tricarboxylic transporters were overexpressed (DCU (> 1.61-fold change) and 0079 (> 4.19-fold change). SSL was responsible for the upregulation of genes involved in the TCA cycle and oxidative phosphorylation, while xylose showed similar results with SSL in the oxidative phosphorylation. [ABSTRACT FROM AUTHOR]