The primary aim of this work was to evaluate various methods of nanocellulose production from wheat straw soda pulp. Wheat straw was cooked in 7% NaOH (over dried material.) at a liquid/solid ratio ...of 10/1 at 100 °C for 150 min to obtain unbleached semichemical pulp. Lignocellulose nanofibers were produced by fibrillation in a high pressure homogenizer, ultrafine friction grinder or twin-screw extruder of cellulose fiber previously extracted from the pulp. Optimizing lignocellulose nanofibers production with the twin-screw extruder required using an enzymatic pretreatment. The three fibrillation methods were assessed for energy use and the resulting lignocellulose nanofibers were characterized in terms of morphology, crystallinity, thermal stability, chemical structure and mechanical properties. Adding lignocellulose nanofibers in proportions from 1.5 to 4.5% to recycled cardboard pulp was found to considerably improve the mechanical properties of recycled fluting even in relation to pulp refining. Thus, the addition of lignocellulose nanofibers doubled Young's modulus and burst index. The technical and energy feasibility of both processes was examined in order to evaluate the suitability of the different nanocellulose production methods for producing cardboard reinforcing agents as compared to conventional mechanical refining methods. This technology provides an economically more viable and competitive production process than industrial mechanical refining, presenting this technology as a candidate to improve the cardboard recycling process, at a lower cost, and increase the maximum recycling cycles that the product can support.
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•Lignocellulose nanofibers were isolated from wheat straw by different treatments.•Twin screw extruder (TSE) requires 5–10 times less energy than other treatments.•LCNFs effect on cardboard properties was similar to industrial mechanical refining.•The use of LCNFs is energy viable compared to mechanical refining.•This technology allows to increase the number of cardboard recycling cycles.
Nanocelluloses with and without residual lignin were isolated from wheat straw. In addition, the effect of TEMPO-mediated oxidation on the production of lignin-containing nanocellulose was studied. ...The different nanocelluloses were used as reinforcing agent in Poly(vinyl alcohol) films. The morphology, crystallinity, surface microstructure, barrier properties, light transmittance, mechanical and antioxidant properties were evaluated. The translucency of films was reduced by the addition of nanocellulose, however, the ability to block UV-light increased from 10% for PVA to >50% using lignin-containing nanocellulose, and 30% for lignin-free samples. The mechanical properties increased considerably, however, for loads higher than 5% a negative trend was observed presumptively due to a clustering of nanocellulose components in PVA matrix. The barrier properties of the films were improved with the use of nanocellulose, especially at small amounts (1–3%). The antioxidant capacity of films was increased up to 10% using lignin-containing nanocellulose compared to 4.7% using PVA.
Biopolymers from forestry biomass are promising for the sustainable development of new biobased materials. As such, lignin and fiber-based biocomposites are plausible renewable alternatives to ...petrochemical-based products. In this study, we have obtained lignin from Spruce biomass through a soda pulping process. The lignin was used for manufacturing biocomposite filaments containing 20% and 40% lignin and using polylactic acid (PLA) as matrix material. Dogbones for mechanical testing were 3D printed by fused deposition modelling. The lignin and the corresponding biocomposites were characterized in detail, including thermo-gravimetric analysis (TGA), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction analysis (XRD), antioxidant capacity, mechanical properties, and scanning electron microscopy (SEM). Although lignin led to a reduction of the tensile strength and modulus, the reduction could be counteracted to some extent by adjusting the 3D printing temperature. The results showed that lignin acted as a nucleating agent and thus led to further crystallization of PLA. The radical scavenging activity of the biocomposites increased to roughly 50% antioxidant potential/cm2, for the biocomposite containing 40 wt % lignin. The results demonstrate the potential of lignin as a component in biocomposite materials, which we show are adequate for 3D printing operations.
The use of lignocellulosic biomass as potential raw material for fractionation and transformation into high value-added products or energy is gathering the attention of scientists worldwide in ...seeking to achieve a green transition in our production systems ....
To uncover the microRNA (miRNA) interactome of the osteoarthritis (OA) pathophysiological process in the cartilage.
We performed RNA sequencing in 130 samples (n=35 and n=30 pairs for messenger RNA ...(mRNA) and miRNA, respectively) on macroscopically preserved and lesioned OA cartilage from the same patient and performed differential expression (DE) analysis of miRNA and mRNAs. To build an OA-specific miRNA interactome, a prioritisation scheme was applied based on inverse Pearson's correlations and inverse DE of miRNAs and mRNAs. Subsequently, these were filtered by those present in predicted (TargetScan/microT-CDS) and/or experimentally validated (miRTarBase/TarBase) public databases. Pathway enrichment analysis was applied to elucidate OA-related pathways likely mediated by miRNA regulatory mechanisms.
We found 142 miRNAs and 2387 mRNAs to be differentially expressed between lesioned and preserved OA articular cartilage. After applying prioritisation towards likely miRNA-mRNA targets, a regulatory network of 62 miRNAs targeting 238 mRNAs was created. Subsequent pathway enrichment analysis of these mRNAs (or genes) elucidated that genes within the 'nervous system development' are likely mediated by miRNA regulatory mechanisms (familywise error=8.4×10
). Herein
encodes neurotrophin-3, which controls survival and differentiation of neurons and which is closely related to the nerve growth factor.
By an integrated approach of miRNA and mRNA sequencing data of OA cartilage, an OA miRNA interactome and related pathways were elucidated. Our functional data demonstrated interacting levels at which miRNA affects expression of genes in the cartilage and exemplified the complexity of functionally validating a network of genes that may be targeted by multiple miRNAs.
Protein self-assemblies modulate protein activities over biological timescales that can exceed the lifetimes of the proteins or even the cells that harbor them. We hypothesized that these timescales ...relate to kinetic barriers inherent to the nucleation of ordered phases. To investigate nucleation barriers in living cells, we developed distributed amphifluoric FRET (DAmFRET). DAmFRET exploits a photoconvertible fluorophore, heterogeneous expression, and large cell numbers to quantify via flow cytometry the extent of a protein’s self-assembly as a function of cellular concentration. We show that kinetic barriers limit the nucleation of ordered self-assemblies and that the persistence of the barriers with respect to concentration relates to structure. Supersaturation resulting from sequence-encoded nucleation barriers gave rise to prion behavior and enabled a prion-forming protein, Sup35 PrD, to partition into dynamic intracellular condensates or to form toxic aggregates. Our results suggest that nucleation barriers govern cytoplasmic inheritance, subcellular organization, and proteotoxicity.
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•Distributed amphifluoric FRET (DAmFRET) quantifies nucleation in living cells•DAmFRET rapidly distinguishes prion-like from non-prion phase transitions•Sequence-intrinsic features determine concentration dependence of nucleation barriers•Prion cross-seeding occurs by conformational templating, not by condensation
Prion phenomena result from protein phase separations that are rate limited by nucleation. Here, Khan et al. introduce a method to quantify nucleation in living cells. By comparing diverse proteins with and without prion behavior, they show that the kinetic barrier to nucleation derives from structural order in the new phase.
As a result of human population growth, the availability of residual lignocellulosic materials from agriculture, forestry, food- and wood-processing industries, and other waste streams is ...continuously increasing ...
The vast majority of calcium carbonate biocrystals differ from inorganic crystals in that they display a patent nanoroughness consisting of lumps of crystalline material (calcite/aragonite) ...surrounded by amorphous pellicles. Scanning transmission electron microscopy coupled with electron energy loss spectroscopy (STEM-EELS) was used to map the calcite secreted by a barnacle chemically and structurally with ultrahigh resolution (down to 1 nm). The material is composed of irregular lumps of calcite (up to two hundred nm in diameter) surrounded by relatively continuous cortexes (up to 20 nm thick) of amorphous calcium carbonate (ACC) and/or nanocalcite plus biomolecules, with a surplus of calcium relative to carbonate. We develop a model by which the separation of the crystalline and amorphous phases takes place upon crystallization of the calcite from a precursor ACC. The organic biomolecules are expelled from the crystal lattice and concentrate in the form of pellicles, where they stabilize minor amounts of ACC/nanocalcite. In this way, we change the previously established conception of biomineral structure and growth.
The present research evaluates the performance of the Nile tilapia (Oreochromis niloticus) (initial weight 11.5 ± 0.07 g) with biofloc technology. For this purpose, spent grains (malted barley) from ...the brewing industry after aerobic fermentation were used, as both a carbon source (suspended solids) and partial substitute for the diets at 0, 10, 20, 30, and 40% levels (settleable solids). The partial 20% substitution of the diet did not have significant effects on the biological parameters: final body weight, weight gained, average body weight, specific growth rate, daily growth index, condition factor, feed conversion ratio, protein efficiency rate, and viscerosomatic and hepatosomatic indices. However, the dietary substitution showed a significant effect on the final biofloc chemical composition. Nitrogen compounds, NH4+, NO2−, and NO3−, were adequate for tilapia cultivation in all the treatments. No clear effect of partial dietary substitution was observed on meat quality parameters: pH, color, water holding capacity, and amino acid and fatty acid profile of fillet. The results suggest that a 20% substitution of the diet for malted barley is suitable for satisfactory biological parameters and Nile tilapia fillet quality.
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