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With approximately 250 000 marine species, the ocean is a vast reservoir of biodiversity and an abundant biological resource of natural polymers and microorganisms producing biopolymer-degrading enzymes.

Our regard to the use of chitin as a material has drastically changed since its discovery.

[EN] The extraction of nanochitin from marine waste has attracted great industrial interest due to its unique properties, namely biodegradability, biocompatibility and as a functional reinforcing agent. Conventional acid hydrolysis isolation of nanochitin requires high temperatures and acid concentration, time and energy. Herein, for the first time, microwave irradiation method was used as an eco-friendly approach to isolate nanochitin from different sources. The isolation conditions were optimized through an experimental Box-Behnken design using surface response methodology. The data showed optimal conditions of 1 M HCl, 10.00 min and 124.75 W to obtain lobster nanocrystals; 1 M HCl, 14.34 min and 50.21 W to obtain shrimp nanocrystals; and 1 M HCl, 29.08 min and 54.08 W to obtain squid pen nanofibres, reducing time and HCl concentration. The obtained isolation yields where of 85.30, 79.92 and 80.59 % for lobster, shrimp and squid, respectively. The morphology of the nanochitins was dependent of the chitin origin, and the lengths of the nanochitins were of 314.74, 386.12 and > 900 nm for lobster, shrimp and squid pen, respectively. The thermal stability of the ensuing nanochitins was maintained after treatment. The results showed that nanochitin could be obtained by using an eco-friendly approach like microwave irradiation. The authors would like to thank the Basque Government (scholarship of young researchers training and project IT1008-16) for supporting financially this research and their gratitude for technical and human support provided by SGIker (UPV/EHU/ERDF, EU). S.C.M.F. is the recipient of an E2S UPPA Research Partnership Chair (MANTA: Marine Materials) supported by the “Investissements d’Avenir” French program managed by ANR (ANR-16-IDEX-0002), the R ́egion Nouvelle-Aquitaine and the Communaut ́e d’Agglom ́eration du Pays Basque, France.

Curcuma longa L. essential oil and anthocyanin extracts contain bioactive compounds such as antioxidant properties and their pigments are able to change color when exposed to different pH or ammonium gas. In this context, the objective of the present work was to develop pH-sensitive intelligent films by adding curcuma oil (composed of essential oils and pigments) and anthocyanin extracts to a chitosan matrix reinforced with alphachitin nanocrystals. The incorporation of curcuma oil, anthocyanins and nanocrystals enhanced the mechanical properties and hydrophobicity; and, decreased water solubility and moisture content. In addition, the films also showed almost total blocking against UV/Vis light at wavelengths below 550 nm. Interestingly, the films were at the same time antioxidant, and sensitive to color change when exposed to ammonia gas and different pH solutions, with greater variations observed when higher concentrations of curcuma oil were added. Hence, these results revealed the potential of these films as intelligent food packaging applications. The authors would like to thank the funding from the Basque Country Government (IT 1008-16). R. F. -M. acknowledge the financial support of the Basque Country Government (scholarship of young researchers training). S.C.M.F. is a recipient of an E2S UPPA MANTA E2S Partnership Chair (Marine Materials) sponsored by the French programme "Investissements d'Avenir" administered by the French National Research Agency (ANR-16-IDEX-IDEX). The authors wish to acknowledge the technical and human assistance received from SGIker (UPV/EHU/ERDF, EU), Spain.

In the present study, chitosan-N-vinyl imidazole was first synthesized and characterized and then its capacity for removal of mercury (II) ions from water was assessed. The graft copolymerization o...

Herein, the effect of three deterpenated fractions from Origanum majorana L. essential oil on the physicochemical, mechanical and biological properties of chitosan/β-chitin nanofibers-based nanocomposite films were investigated. In general, the incorporation of Origanum majorana L. original essential oil or its deterpenated fractions increases the opacity of the nanocomposite films and gives them a yellowish color. The water solubility decreases from 58% for chitosan/β-chitin nanofibers nanocomposite film to around 32% for the nanocomposite films modified with original essential oil or its deterpenated fractions. Regarding the thermal stability, no major changes were observed, and the mechanical properties decreased. Interestingly, data show differences on the biological properties of the materials depending on the incorporated deterpenated fraction of Origanum majorana L. essential oil. The nanocomposite films prepared with the deterpenated fractions with a high concentration of oxygenated terpene derivatives show the best antifungal activity against Aspergillus niger, with fungal growth inhibition of around 85.90%. Nonetheless, the only nanocomposite film that does not present cytotoxicity on the viability of L929 fibroblast cells after 48 and 72 h is the one prepared with the fraction presenting the higher terpenic hydrocarbon content (87.92%). These results suggest that the composition of the deterpenated fraction plays an important role in determining the biological properties of the nanocomposite films. This research was funded by the Basque Country Government (IT 1008-16).

Herein, the effect of three deterpenated fractions from Origanum majorana L. essential oil on the physicochemical, mechanical and biological properties of chitosan/β-chitin nanofibers-based nanocomposite films were investigated. In general, the incorporation of Origanum majorana L. original essential oil or its deterpenated fractions increases the opacity of the nanocomposite films and gives them a yellowish color. The water solubility decreases from 58% for chitosan/β-chitin nanofibers nanocomposite film to around 32% for the nanocomposite films modified with original essential oil or its deterpenated fractions. Regarding the thermal stability, no major changes were observed, and the mechanical properties decreased. Interestingly, data show differences on the biological properties of the materials depending on the incorporated deterpenated fraction of Origanum majorana L. essential oil. The nanocomposite films prepared with the deterpenated fractions with a high concentration of oxygenated terpene derivatives show the best antifungal activity against Aspergillus niger, with fungal growth inhibition of around 85.90%. Nonetheless, the only nanocomposite film that does not present cytotoxicity on the viability of L929 fibroblast cells after 48 and 72 h is the one prepared with the fraction presenting the higher terpenic hydrocarbon content (87.92%). These results suggest that the composition of the deterpenated fraction plays an important role in determining the biological properties of the nanocomposite films.

Mycosporines and mycosporine-like amino acids have been described as natural sunscreens and antioxidant compounds presenting a great potential for health and cosmetic applications. Herein, an untargeted screening approach for mycosporines and mycosporine-like amino acids (MAAs) was developed by the coupling of zwitterionic hydrophilic interaction liquid chromatography (HILIC) with multistage electrospray mass spectrometry MS2/MS3 using an Orbitrap analyzer and fragment ion search (FISh). This method was applied to study the mycosporine and MAA contents of five algae extracted using a 50% methanol solution and sonication. Candidate-MAAs were detected by mining eight characteristic fragment ions in their HILIC data-dependent MS2 mass spectrum. Their exact masses were measured with 3 ppm mass accuracy and their structures were elucidated on the basis of the MS3/MS4 mass spectra. The method developed was validated with a targeted analysis using an extract of Gymnogongrus devoniensis which confirmed the detection of 14 MAAs reported in the literature. In addition, 23 previously unreported MAAs were detected and the structures could be assigned for seven of them. The developed method was applied to the analysis of four algae: Gelidium sesquipedale, Halopithys incurva, Porphyra rosengurtii and Cystoseira tamariscifolia allowing the detection of MAAs, including some reported here for the first time.

International audience; -In the present work, nanocomposite films based on poly(vinyl alcohol) (PVA) containing different amounts of Origanum vulgare essential oil (OEO, 0, 0.5, 1, 1.5 and 2% v/v) were reinforced with 0.5% (w/v) of alphachitin nanocrystals (α-CHNC, from shrimp and from lobster) and prepared by solvent casting. Another set of films was prepared without α –CHNC to assess the effect of the nanocrystals on the final properties of the films. The obtained nanocomposite films were homogeneous and showed better thermal stability and mechanical properties. After exposure the nanocomposite films to ultraviolet radiation, the obtained data revealed that the presence of α-CHNC into the materials has a retarding effect on their loss of mechanical properties. It was also shown that the antioxidant activity and the total phenolic content of the materials increased with the augmentation of OEO and with the antioxidant release time. Interestingly, the nanocomposite films made of chitin nanocrystals from shrimp showed better total phenolic content than the unfilled films and the nanocomposite films made of chitin nanocrystals from lobster over the first 48 h. Henceforward, this study demonstrated the potential of the nanocomposite films based on PVA, OEO and reinforced with α-CHNC for active food-packaging applications.

International audience; The review covers recent literature on the ocean as both a source of biotechnological tools and as a source of bio-inspired materials. The emphasis is on marine biomacromolecules namely hyaluronic acid, chitin and chitosan, peptides, collagen, enzymes, polysaccharides from algae, and secondary metabolites like mycosporines. Their specific biological, physicochemical and structural properties together with relevant applications in biocomposite materials have been included. Additionally, it refers to the marine organisms as source of inspiration for the design and development of sustainable and functional (bio)materials. Marine biological functions that mimic reef fish mucus, marine adhesives and structural colouration are explained.

In this paper, gas permeability studies were performed on materials based on natural rubber/acrylonitrile butadiene rubber blends and nanoclay incorporated blend systems. The properties of natural rubber (NR)/nitrile rubber (NBR)/nanoclay nanocomposites, with a particular focus on gas permeability, are presented. The measurements of the barrier properties were assessed using two different gases—O2 and CO2—by taking in account the blend composition, the filler loading and the nature of the gas molecules. The obtained data showed that the permeability of gas transport was strongly affected by: (i) the blend composition—it was observed that the increase in acrylonitrile butadiene rubber component considerably decreased the permeability; (ii) the nature of the gas—the permeation of CO2 was higher than O2; (iii) the nanoclay loading—it was found that the permeability decreased with the incorporation of nanoclay. The localization of nanoclay in the blend system also played a major role in determining the gas permeability. The permeability of the systems was correlated with blend morphology and dispersion of the nanoclay platelets in the polymer blend.

International audience; Industrial sea food residues, mainly crab and shrimp shells, are considered to be the most promising and abundant source of chitin. In-depth understanding of the biological properties of chitin and scientific advancements in the field of nanotechnology have enabled the development of high-performance chitin nanomaterials. Nanoscale chitin is of great economic value as an efficient functional and reinforcement material for a wide range of applications ranging from water purification to tissue engineering. The use of polymers and nanochitin to produce (bio) nanocomposites offers a good opportunity to prepare bioplastic materials with enhanced functional and structural properties. Most processes for nanochitin isolation rely on the use of chemical, physical or mechanical methods. Chitin-based nanocomposites are fabricated by various methods, involving electrospinning, freeze drying, etc. This review discusses the progress and new developments in the isolation and physico-chemical characterization of chitin; it also highlights the processing of nanochitin in various composite and functional materials.

Copper (Cu (II)) is one of the most toxic heavy metals usually found in the environment. Thus its removal from aqueous waste streams is an important issue in nowadays. The present work focuses on the comparison of the copper adsorption on chitin-based adsorbents, i.e. chitin (CH), chitosan (CS) and chitosan- ethylenediaminetetra-acetic acid (CS-EDTA). Chitin derivatives are carbohydrate materials well known to remove heavy metal ions from aqueous solutions. The effects of contact time, initial concentration, the temperature, pH, and mass of the adsorbent in the adsorption process were studied. The adsorption isotherms were well simulated by Langmuir and Freundlich models. The maximum adsorption capacity of CH, CS and CS-EDTA at 25 °C, pH 7.0 was found to be 58, 67 and 110 mg g−1, respectively. Thermodynamic parameters of adsorption processes such as Gibb's free energy (ΔG0), standard enthalpy (ΔH°) and entropy (ΔS0) were also calculated. The results showed that the studied materials could be used as effective adsorbents for removal of copper from water.

Bionanocomposite films prepared with melt compounding and film blowing were evaluated for packaging applications. The nanocomposite masterbatch with 75 wt.% polylactic acid (PLA), 5 wt.% chitin nanocrystals (ChNCs) and 20 wt.% glycerol triacetate plasticizer (GTA) was melt compounded and then diluted to 1 wt.% ChNCs with PLA and polybutylene adipate-co-terephthalate (PBAT) prior to film blowing. The morphological, mechanical, optical, thermal and barrier properties of the blown nanocomposite films were studied and compared with the reference material without ChNCs. The addition of 1 wt.% ChNCs increased the tear strength by 175% and the puncture strength by 300%. Additionally, the small amount of chitin nanocrystals affected the glass transition temperature (Tg), which increased 4 °C compared with the reference material and slightly enhanced the films degree of crystallinity. The chitin nanocomposite also had lower fungal activity and lower electrostatic attraction between the film surfaces; leading to easy opening of the plastic bags. The barrier and optical properties as well as the thermal degradation of the films were not significantly influenced by the addition of chitin nanocrystals. Keywords: Nanocomposite, Extrusion, Nanocrystals, Mechanical properties, Thermal properties, Film blowing

Articular cartilage degeneration is one of the most common causes of pain and disability in middle-aged and older people. Tissue engineering (TE) has shown great therapeutic promise for this condition. The design of cartilage regeneration constructs must take into account the specific characteristics of the cartilaginous matrix, as well as the avascular nature of cartilage and its cells&rsquo, peculiar arrangement in isogenic groups. Keeping these factors in mind, we have designed a 3D porous scaffold based on genipin-crosslinked chitosan/chitin nanocrystals for spheroid chondral differentiation of human adipose tissue-derived mesenchymal stem cells (hASCs) induced in hypoxic conditions. First, we demonstrated that, under low oxygen conditions, the chondrospheroids obtained express cartilage-specific markers including collagen type II (COL2A1) and aggrecan, lacking expression of osteogenic differentiation marker collagen type I (COL1A2). These results were associated with an increased expression of hypoxia-inducible factor 1&alpha, which positively directs COL2A1 and aggrecan expression. Finally, we determined the most suitable chondrogenic differentiation pattern when hASC spheroids were seeded in the 3D porous scaffold under hypoxia and obtained a chondral extracellular matrix with a high sulphated glycosaminoglycan content, which is characteristic of articular cartilage. These findings highlight the potential use of such templates in cartilage tissue engineering.

[EN] A series of bionanocomposite films based on chitosan, reinforced with chitin nanocrystals, were developed, and assessed in terms of dielectric behaviour and conductivity by using an experimental methodology that allows avoiding the conductivity contribution and the exclusion of contact and interfacial polarization effects. The dielectric relaxations at low and high frequency and temperatures were modeled by Havriliak-Negami functions. Below the glass transition temperature (Tg), the gamma and beta relaxations were observed, which were related to intramolecular and non-cooperative segmental movements. At higher temperatures, an intermolecular and cooperative macromolecular movement, related to the glass transition, gave rise to alpha-relaxation. In addition, two over-Tg p(I) and p(II) relaxations were found, which were related to the displacement of dipoles in the disordered structure of bionanocomposites. The addition of chitin nanocrystals did not affect the apparent activation energy Ea of the gamma-relaxation. However, it decreased the Ea of the beta-relaxation and increased the free volume at temperatures in the vicinities of the alpha-relaxation. Finally, the electric conductivity of the bionanocomposites was lower than that of neat chitosan and chitin due to the interaction between the-OH and-NH2 groups that reduced the ionic mobility, along with the increase of free volume, with the subsequent separation of phases., The European Regional Development Funds and the Spanish Ministry of Science and Innovation for the concession of Research Projects ENE2014-53734-C2-1-R, UPOV13-3E-1947 and ENE2017-86711-C3-1-R are appreciated. Generalitat Valenciana is acknowledged for the project APOSTD14/041 for JD Badia and GRISOLIA/2002/003 for R. Teruel-Juanes. The authors are thankful for the financial support from the Department of Education of the Basque Government (IT1008-18).

International audience; The precise role and value of incorporating nanoforms in biologically active matrices for medical applications is not known. In our current work, we incorporate two chitin nanoforms (i.e., nanocrystals or nanofibers) into Genipin-chitosan crosslinked matrices. These materials were studied as 2D films and 3D porous scaffolds to assess their potential as primary support and guidance for stem cells in tissue engineering and regenerative medicine applications. The incorporation of either nanoforms in these 2D and 3D materials reveals significantly better swelling properties and robust mechanical performance in contrast to nanoform-free chitosan matrices. Furthermore, our data shows that these materials, in particular, incorporation of low concentration chitin nanoforms provide specific topological cues to guide the survival, adhesion, and proliferation of human adipose-derived stem cells. These findings demonstrate the potential of Genipin-chitosan crosslinked matrices impregnated with chitin nanoforms as value added materials for stem cell-based biomedical applications.

Due to its intractable structure and inherent insoluble nature, chitin was for a long time an underutilized resource. The increasing interest in the use of chitin as a source of nanostructured mate ...

Added-value bionanocomposite films were obtained using exclusively oceanic biomass, i.e. chitin nanofillers (nanocrystals- CHNC and nanofibers- CHNF) and chitosan (CS) isolated from Cervimunida johni (yellow lobster) wastes. From these raw materials two sets of bionanocomposite films (CS/CHNC and CS/CHNF) using CS as matrix and CHNC or CHNF as functional agents were prepared by solvent evaporation-casting approach. The bionanocomposite films’ chemistry, structure, mechanical and thermal properties and fungal growth inhibition toward A. niger were analyzed, and the effect of the CHNC and CHNF on the final properties of CS-based bionanocomposite films was evaluated and compared. The data demonstrated that the final properties were dependent of the content and nano nature (size and shape) of chitin nanofillers incorporated in the CS matrix. The CS-based bionanocomposite films reinforced with CHNF showed superior mechanical properties than those prepared with CHNC. Moreover, antifungal assessment demonstrated that CS/CHNF bionanocomposite films presented an inhibitory effect (FGI >80%) against A. Niger . Unquestionably, these bionanocomposite films show a great potential to be used in packaging applications and medical devices.

The main goal of this work was the development of photoactive multilayer films. Taking into account that chitosan is a biodegradable, biocompatible, nontoxic, and antibacterial biopolymer, the fabrication of chitosanbased multilayer films can be an interesting pathway to obtain biopolymer-based films in which properties can be combined with a light-responsive material, such as an azobenzene-containing polymer. In particular, the layer-by-layer technique was used for the fabrication of the optically active films consisting of alternating layers of chitosan and an azopolymer. The influence of the pH and the number of bilayers on the structure and properties of the films was investigated by different experimental techniques and it was found that the roughness and elastic modulus of the multilayer films increased with the decrease in chitosan solution pH. Besides, induced birefringence measurements revealed that a higher level of photoorientation was attained with the decrease in pH and the increase in bilayer number of the developed films. © 2015 Scrivener Publishing LLC.

As, in the market, poly (lactic acid) (PLA) is the most used polymer as an alternative to conventional plastics, and as functionalized chitin nanocrystals (CHNC) can provide structural and bioactive properties, their combination sounds promising in the preparation of functional nanocomposite films for sustainable packaging. Chitin nanocrystals were successfully modified via acylation using anhydride acetic and dodecanoyl chloride acid to improve their compatibility with the matrix, PLA. The nanocomposite films were prepared by extrusion/compression approach using different concentrations of both sets of functionalized CHNC. This investigation brings forward that both sets of modified CHNC act as functional agents, i.e., they slightly improved the hydrophobic character of the PLA nanocomposite films, and, very importantly, they also enhanced their antifungal activity. Nonetheless, the nanocomposite films prepared with the CHNC modified with dodecanoyl chloride acid presented the best properties. The authors are thankful for the financial support from the European Commission through the European Project ECLIPSE (NMP-280786); the Department of Education of the Basque Government through project IT1008-16; and scholarship of young researchers training and project. The authors also acknowledge the technical and human support of General Research Services (SGIker) from the UPV/EHU for water vapor transmission and oxygen transmission analyses.

cited By 20; International audience; Chitin nano-size fillers, i.e. nanocrystals (CHNC) and nanofibers (CHNF), were incorporated in thermoplastic starch matrix via melt-mixing. The two types of thermoplastic starch-based nano-biocomposites (S/CHNC and S/CHNF) were characterized and compared in terms of morphology, chemical and crystal structure, thermal and mechanical properties, and water resistance. In general, all thermoplastic starch-based nano-biocomposites showed better thermal stability, mechanical properties, and storage modulus than thermoplastic starch matrix without chitin nano-size fillers. This can be linked to the good dispersion of the nano-size fillers in the matrix, resulting from their chemical similarity, and also to the strong nano-size fillers-matrix adhesion by hydrogen bonding interactions. The results showed that the final properties of the nano-biocomposites were dependent of the concentration and type of chitin nano-size filler introduced in the thermoplastic starch matrix. In general, the thermoplastic starch-based nano-biocomposites prepared with chitin nanofibers showed better thermal and mechanical properties and storage modulus than those prepared with chitin nanocrystals. © 2014 Elsevier B.V.

cited By 31; International audience; In order to obtain cellulose nanoentities like nanofibres (CNF) and nanocrystals (CNC) from sisal (S), hemp (He) and flax (F) fibres, a new succession of specific chemical treatments including extractives (E), prealkalization (PA), alkalization (A), acetylation (Ac) and acid hydrolysis (H) treatments have been developed. Cellulose nanoentities obtained have been characterized by different techniques. FTIR spectra confirmed the removal of non-cellulosic components after chemical treatments. XRD results showed that all samples exhibited cellulose I crystalline structure and the crystallinity index of cellulose nanoentities was increased about 30% relative to raw fibres owing to removal of non-cellulosic components. The thermal stability of samples decreased after using an acid medium. AFM images confirmed that cellulose nanofibres and nanocrystals were obtained. © 2014 Elsevier B.V.

cited By 13; International audience; In the present work, we propose a simple and straightforward procedure to prepare antibacterial transparent pullulan films by functionalization of pullulan powder with 3-aminopropyltrimethoxysilane. The introduction of active aminopropyl groups into the pullulan polymeric backbone imparts antimicrobial activity against Gram-positive ( Staphylococcus aureus) and Gram-negative bacteria ( Escherichia coli). In addition, the antimicrobial pullulan maintains its filmogenic ability and the films showed reasonable mechanical properties (Young modulus of 1.8GPa and tensile strength of 21MPa) and improved thermal stability (increment of 10°C on the maximum degradation temperature), opening the possibility for application in functional food packaging films and coatings. © 2013 Elsevier Ltd.

The hybrid inorganic/organic nanopapers based on bacterial cellulose and different type of sol–gel synthesized nanoparticles are fabricated. A simple, rapid, low-cost pathway based on a diffusion step of sol–gel nanoparticles into swollen bacterial cellulose membrane via orbital incubator is developed. This alternative pathway allows to keeping intact the 3D network of the bacterial cellulose membrane while sol–gel nanoparticles are formed in situ and anchored on the nanofibers surface. Titanium, vanadium oxide nanoparticles and a mixture of both are used to functionalize bacterial cellulose membrane. Fabricated hybrid inorganic/organic nanopapers are characterized by thermogravimetric analysis, X-ray diffraction spectroscopy, scanning electron microscopy, energy dispersive X-ray spectroscopy, MTS mechanical testing, UV–vis spectroscopy, colorimeter and semiconductor analyzer. Synthesized photochromic hybrid nanopapers modified with vanadium and titanium oxide nanoparticles can find potential application as sensitive displays, biosensors and other optical devices.

An active protective coating based on chitosan (CTS) polymer with corrosion inhibitor 2-mercaptobenzothiazole (MBT) is reported. Structural and morphological analysis indicated that MBT is present in large amounts within the CTS matrix without affecting detrimentally the properties of CTS. More relevant, the release of MBT is dependent upon pH, resulting from the contribution of two factors: the chemistry of CTS (low pH) and the solubility of MBT (high pH). The performance of CTS-MBT was assessed using electrochemical impedance spectroscopy (EIS) and found to be promising as a temporary coating for active corrosion protection. (C) 2013 The Electrochemical Society. [DOI: 10.1149/2.002306eel] All rights reserved.

cited By 25; International audience; Bionanocomposites with improved properties based on two microbial polysaccharides, pullulan and bacterial cellulose, were prepared and characterized. The novel materials were obtained through a simple green approach by casting water-based suspensions of pullulan and bacterial cellulose and characterized by TGA, RDX, tensile assays, SEM and AFM. The effect of the addition of glycerol, as a plasticizer, on the properties of the materials was also evaluated. All bionanocomposites showed considerable improvement in thermal stability and mechanical properties, compared to the unfilled pullulan films, evidenced by the significant increase in the degradation temperature (up to 40 °C) and on both Young's modulus and tensile strength (increments of up to 100 and 50%, for films without glycerol and up to 8,000 and 7,000% for those plasticized with glycerol). Moreover, these bionanocomposite films are highly translucent and could be labelled as sustainable materials since they were prepared entirely from renewable resources and could find applications in areas as organic electronics, dry food packaging and in the biomedical field. © 2012 Springer Science+Business Media B.V.

This review provides a brief overview of the recent research efforts carried out at the CICECO laboratory of the University of Aveiro on novel materials based on chitosan within the background of previous investigations of similar counterparts. Most of this work is devoted to different modes of combining chitosans of various molecular weights and degrees of deacetylation (including appropriately modified chitosans providing either fluorescent properties or water solubility) with cellulose fibres of various sizes (standard to nanosize), morphologies (conventional papers, nanofibrillated or bacterial strands) and assemblies (composites or paper coating and impregnation). Additionally, the radical transformation of chitin and chitosan low-quality residues into viscous polyols by a straightforward oxypropylation is also discussed. The results of these investigations show the remarkable potential of chitosan as a source of promising blends and composites, among other novel materials.