Xyloglucan-Cellulose Nanocrystals Mixtures: A Case Study of Nanocolloidal Hydrogels and Levers for Tuning Functional Properties.

The development of fully biobased hydrogels obtained by simple routes and in the absence of toxic or environmentally harmful reagents is a major challenge in meeting new societal demands. In this work, we discuss the development of hydrogels made from cellulose nanocrystals (CNCs) and xyloglucan (XG), two non-toxic, renewable, and biobased components. We present three strategies to fine-tune the functional properties.

Flexoelectric and piezoelectric effects in micro- and nanocellulose films.

In this work, we evaluated the flexoelectric and piezoelectric contributions to the overall macroscopic polarization in cellulose films. To this end, the flexoelectric μ and transverse effective piezoelectric e coefficients of cellulose films were determined using cantilever beam bending. The experiments were based on theoretical developments allowing to separate the flexoelectric from the piezoelectric contribution, represented by an effective flexoelectric coefficient, μ, depending on both e and μ.

Optimized Lytic Polysaccharide Monooxygenase Action Increases Fiber Accessibility and Fibrillation by Releasing Tension Stress in Cellulose Cotton Fibers.

Lytic polysaccharide monooxygenase (LPMO) enzymes have recently shaken up our knowledge of the enzymatic degradation of biopolymers and cellulose in particular. This unique class of metalloenzymes cleaves cellulose and other recalcitrant polysaccharides using an oxidative mechanism. Despite their potential in biomass saccharification and cellulose fibrillation, the detailed mode of action of LPMOs at the surface of cellulose fibers still remains poorly understood and highly challenging to investigate.

Xyloglucan-cellulose nanocrystal-chitosan double network hydrogels for soft actuators.

Hydrogels are materials consisting in a three-dimensional hydrophilic polymer network swollen by a large amount of water. An efficient strategy to elaborate hydrogels consists in establishing double polymer networks in order to achieve high strengthening effect associated with other properties such as transparency or tailored swelling capacities. In this work, we prepared cellulose nanocrystals (CNC)-based hydrogels with double network architecture.

Engineered Multilayer Microcapsules Based on Polysaccharides Nanomaterials.

The preparation of microcapsules composed by natural materials have received great attention, as they represent promising systems for the fabrication of micro-containers for controlled loading and release of active compounds, and for other applications. Using polysaccharides as the main materials is receiving increasing interest, as they constitute the main components of the plant cell wall, which represent an ideal platform to mimic for creating biocompatible systems with specific responsive properties. Several researchers have recently described methods for the preparation of microcapsules with various sizes and properties using cell wall polysaccharide nanomaterials.

Asymmetric modification of cellulose nanocrystals with PAMAM dendrimers for the preparation of pH-responsive hairy surfaces.

In this work, we present a straightforward method to attach a globular dendrimer at the reducing end of cellulose nanocrystals obtained from tunicates (t-CNC). We investigated the first four generations of poly(amidoamine) dendrimers (PAMAMs G0 to G3) to obtain hybrid t-CNCs. The aggregation behavior of hybrid t-CNCs was studied by dynamic light scattering (DLS) and scanning transmission electron microscopy (STEM); and interactions of these asymmetric nanoparticles with gold surface were elucidated using quartz crystal microbalance with dissipation (QCM-D) and surface plasmon resonance (SPR).

pH-Responsive Properties of Asymmetric Nanopapers of Nanofibrillated Cellulose.

Inspired by plant movements driven by the arrangement of cellulose, we have fabricated nanopapers of nanofibrillated cellulose (NFC) showing actuation under pH changes. Bending was achieved by a concentration gradient of charged groups along the film thickness. Hence, the resulting nanopapers contained higher concentration of charged groups on one side of the film than on the opposite side, so that pH changes resulted in charge-dependent asymmetric deprotonation of the two layers.

Meaning of xylan acetylation on xylan-cellulose interactions: A quartz crystal microbalance with dissipation (QCM-D) and molecular dynamic study.

In plant cell walls, xylan chains present various substituents including acetate groups. The influence of the acetyl substitution on the organization of xylan-cellulose complexes remains poorly understood. This work combines in vitro and in silico approaches to decipher the functional role of acetyl groups on the xylan/cellulose interaction.

Influence of the carbohydrate-binding module on the activity of a fungal AA9 lytic polysaccharide monooxygenase on cellulosic substrates.

Background: Cellulose-active lytic polysaccharide monooxygenases (LPMOs) secreted by filamentous fungi play a key role in the degradation of recalcitrant lignocellulosic biomass. They can occur as multidomain proteins fused to a carbohydrate-binding module (CBM). From a biotech perspective, LPMOs are promising innovative tools for producing nanocelluloses and biofuels, but their direct action on cellulosic substrates is not fully understood.

Star-like Supramolecular Complexes of Reducing-End-Functionalized Cellulose Nanocrystals.

In this work, we take advantage of the parallel organization of cellulose chains in cellulose I yielding an inherent chemical asymmetry of cellulose nanocrystals, i.e., reducing vs nonreducing end, to selectively modify only one end of these rigid rodlike crystals to be used as a linking point for the formation of supramolecular structures.

Lytic polysaccharide monooxygenases (LPMOs) facilitate cellulose nanofibrils production.

Background: Lytic polysaccharide monooxygenases (LPMOs) are copper-dependent enzymes that cleave polysaccharides through an oxidative mechanism. These enzymes are major contributors to the recycling of carbon in nature and are currently used in the biorefinery industry. LPMOs are commonly used in synergy with cellulases to enhance biomass deconstruction.

Isolated pulmonary interstitial glycogenosis associated with alveolar growth abnormalities: A long-term follow-up study.

Introduction: Pulmonary interstitial glycogenosis (PIG) is a rare infant interstitial lung disease characterized by an increase in the number of interstitial mesenchymal cells, presenting as enhanced cytoplasmic glycogen, and is considered to represent the expression of an underlying lung development disorder.

Methods: This study describes the clinical, radiological, and functional characteristics and long-term outcomes (median 12 years) of nine infants diagnosed with isolated PIG associated with alveolar simplification in the absence of other diseases.

Results: All patients presented with tachypnea.

The yeast encodes functional lytic polysaccharide monooxygenases.

Background: Lytic polysaccharide monooxygenases (LPMOs) are a class of powerful oxidative enzymes that have revolutionized our understanding of lignocellulose degradation. Fungal LPMOs of the AA9 family target cellulose and hemicelluloses. AA9 LPMO-coding genes have been identified across a wide range of fungal saprotrophs (Ascomycotina, Basidiomycotina, etc.

Lytic polysaccharide monooxygenases disrupt the cellulose fibers structure.

Lytic polysaccharide monooxygenases (LPMOs) are a class of powerful oxidative enzymes that breakdown recalcitrant polysaccharides such as cellulose. Here we investigate the action of LPMOs on cellulose fibers. After enzymatic treatment and dispersion, LPMO-treated fibers show intense fibrillation.

Kinetic aspects of the adsorption of xyloglucan onto cellulose nanocrystals.

In this work, the adsorption of a neutral flexible polysaccharide, xyloglucan (XG), onto thin cellulose nanocrystal (CNC) surfaces has been investigated to get more insight into the CNC-XG association. Gold-coated quartz crystals were spin-coated with one layer of CNC, and XG adsorption was monitored in situ using a quartz crystal microbalance with dissipation (QCM-D). The adsorption of XG under flow at different concentrations did not result in the same surface concentration, which evidenced a kinetically controlled process.

Exploring architecture of xyloglucan cellulose nanocrystal complexes through enzyme susceptibility at different adsorption regimes.

Xyloglucan (XG) is believed to act as a cementing material that contributes to the cross-linking and mechanical properties of the cellulose framework in plant cell walls. XG can adsorb to the cellulose nanocrystal (CNC) surface in vitro in order to simulate this in vivo relationship. The target of our work was to investigate the sorption behavior of tamarind seed XG on CNC extracted from cotton linters at different XG/CNC concentration ratios, that is, different adsorption regimes regarding the XG-CNC complex organization and the enzymatic susceptibility of XG.

In vitro anti-inflammatory activity of phenolic rich extracts from white and red common beans.

According to epidemiological evidence, diets rich in fruits and vegetables can reduce the incidence of several chronic diseases that share an inflammatory component. These protective effects are attributed, in part, to the occurrence of different antioxidant components, mainly phenolic compounds. Our aim was to characterise phenolic composition, and to determine antioxidant and anti-inflammatory activities of phenolic rich extracts obtained from two kinds of common beans, white kidney beans (WKB) and round purple beans (RPB).

Impact of ionic strength on chitin nanocrystal-xyloglucan multilayer film growth.

The impact of the ionic strength on the film growth has been studied for the architectures composed of chitin nanocrystals (ChiNC) and xyloglucan (XG) to better understand the fabrication process of multilayer films. The formation of ChiNC-XG assemblies was monitored by quartz crystal microbalance with dissipation (QCM-D) and multilayer films were fabricated by the spin-coating assisted layer-by-layer (LbL) procedure. Films were prepared from 1 g L(-1) ChiNC dispersions at pH 4 without and with the addition of NaCl (0 and 5 mM, respectively) and 0.

Chitin nanocrystal-xyloglucan multilayer thin films.

For the first time, the adsorption of xyloglucan (XG) on chitin nanocrystals (ChiNC) surface was proved using quartz crystal microbalance with dissipation (QCM-D) and by successfully building up spin-coated assisted layer-by-layer (LbL) structures on solid substrates. Several parameters in the adsorption process, such as ChiNC concentrations (0.5-3.

Isolation and characterization of a glucan-type polysaccharide from the red pine mushroom, Lactarius deliciosus (Higher Basidiomycetes).

A novel glucan-type polysaccharide has been isolated from the fruiting bodies of the edible mushroom Lactarius deliciosus. Two successive extractions (cold aqueous extraction at 25°C and hot aqueous extraction at 100°C) were performed, and the same polysaccharide was obtained in both fractions. The purity of the polysaccharide was evaluated by size exclusion chromatography.