Bacterial Cellulose Nanocrystals Research Articles

Bacterial cellulose nanocrystals obtained through enzymatic and acidic routes: A comparative study of their main properties and in vitro biological responses

Cellulose nanocrystals (CNCs) are crystalline domains isolated from cellulosic fibers. They have been utilized in a wide range of applications, such as reinforcing fillers, antibacterial agents and manufacturing of biosensors. Whitin this context, the aim of this work was to obtain and analyze CNCs extracted from bacterial nanocellulose (BNC) using two distinct methods combined with milling pre-treatment: an acidic hydrolysis using 64 % sulfuric acid and an enzymatic hydrolysis using a commercial cellulase enzyme mixture. The CNCs obtained from the enzymatic route (e-CNCs) were observed to be spherical nanoparticles with diameter of 56 ± 11 nm. In contrast, the CNCs from the acid hydrolysis (a-CNCs) appeared as needle-shaped nanoparticles with a high aspect ratio with lengths/widths of 158 ± 64 nm/11 ± 2 nm. The surface zeta potential (ZP) of the a-CNCs was −30,8 mV, whereas the e-CNCs has a potential of +2.70 ± 3.32 mV, indicating that a-CNCs consisted of negatively charged particles with higher stability in solution. Although the acidic route resulted in nanocrystals with a slightly higher crystallinity index compared to the enzymatic route, e-CNCs was found to be more thermally stable than BNC and a-CNCs. Here, we also confirmed the safety of a-CNCs and e-CNCs using L929 cell line. Lastly, this article describes two different CNCs synthesis approaches that leads to the formation of nanoparticles with different dimensions, morphology and unique physicochemical properties. To the best of our knowledge, this is the first study to yield spherical nanoparticles as a result of BNC enzymatic treatment.

Nanocellulose-Enhanced, Easily Processable Cellulose-Based Flexible Pressure Sensor for Wearable Epidermal Sensing.

Flexible pressure sensors (FPSs) based on biomass materials have gained considerable attention for their potential in wearable electronics, human-machine interaction, and environmental protection. Herein, flexible silver nanowire-dual-cellulose paper (SNdCP) containing common cellulose fibers, cellulose nanofibers (CNFs), and silver nanowires (AgNWs) for FPSs was assembled by a facile papermaking strategy. Compared with bacterial cellulose (BC) and cellulose nanocrystals (CNCs), CNFs possess better dimensions and reinforcement, which enables the composite paper to exhibit better mechanical properties (tensile stress of 164.65 MPa) and electrical conductivity (11600 S·m-1), providing more possibilities for FPSs. Benefiting from these advantages, we construct an easily processable and sensitive human-interactive FPS based on a composite paper with high sensitivity (0.050 kPa-1), fast response/recovery time (158/95 ms), and exceptional stability (>1000 bending cycles), capable of responding to finger motions, voice recognition, and human pulses; through further employment as the array unit and a control circuit, the observed highly adaptive mechano-electric transformability and functions are well maintained. Overall, a facile and versatile strategy with the potential to provide clues for the fabrication of cellulose-based FPSs with outstanding performance was introduced.

Fabrication of novel antimicrobial nanocomposite films based on polyvinyl alcohol, bacterial cellulose nanocrystals, and boric acid for food packaging

Fabrication of novel antimicrobial nanocomposite films based on polyvinyl alcohol, bacterial cellulose nanocrystals, and boric acid for food packaging

Development of Bacterial Cellulose Herbal Wound Dressing

Wound dressings play an essential role in wound care and healing, but the price is expensive for patients who have to treat for a long time such as patients from burns, scalds, etc. The objective of the research is to develop a wound dressing made with bacterial cellulose and local herb that has antibacterial properties, is cheap, and can be created by yourself. The bacterial cellulose (BC) produced from Acetobactor xylinum using coconut water waste to reduce costs. Its structure was changed to bacterial cellulose nanocrystals (BCNC) by acid hydrolysis, dried in 2 methods: Oven dried at 50 °C (dy) or freeze dried (fd). Then, herbal dressings were produced as a composite BC with herbs in 2 forms: A solution, i.e. C. Odorata leaf extract solution and a colloid, i.e. C. hystrix essential oil nanocapsule. The results for the production of a wound dressing showed that fd-BCNC had good quality, good fiber dispersion, high porosity and no antibacterial activity. It is suitable as a primary or secondary wound dressing, that does not help in wound healing. When fd-BCNC was loaded with herbs in 2 forms, it was found to be stable at room temperature, water adsorption, water vapor permeability and inhibit Staphylococcus aureus and Escherichia coli. Especially fd-BCNC of nanocapsule of C. hystrix peel essential oil has the best antibacterial effect. Therefore, you can apply this developed wound dressing to herbs used specifically for healing wounds. Moreover, we believe that this research will be a database that can be expanded to commercial production. HIGHLIGHTS Bacterial cellulose is produced using coconut water waste as culture medium Freeze-dried Bacterial cellulose nanocrystals is a promising for non antibacterial wound dressing Freeze-dried Bacterial cellulose nanocrystals composite with herbs are a promising for anti-bacterial wound dressing GRAPHICAL ABSTRACT

Determination of thiram in fruit juices using a bacterial cellulose nanocrystal-based SERS substrate

Pesticide residues in agri-foods have risk to human health and one solution is to develop simple and accurate methods for rapid detection. We developed a SERS sensor composed of gold nanoparticles (AuNPs) and bacterial cellulose nanocrystal (BCNC) to detect thiram in fruit juice. BCNC-SO3H was used as a stabilizer to support AuNPs via electrostatic repulsion, fabricating a BCNC-AuNPs SERS substrate with uniformly distributed AuNPs. This BCNC-AuNPs SERS substrate was applied to determine thiram residues in peach juice, apple juice, and grape juice with the limits of detection of 0.036 ppm, 0.044 ppm, and 0.044 ppm, respectively. The whole test took 12 min including sample preparation and analysis. The detection limits meet the maximum residue levels of thiram in fruit juices required by China, Europe and North America, indicating that this BCNC-based substrate could serve as a satisfactory SERS sensor for pesticide residue monitoring in the food supply chain.

Bacterial cellulose nanocrystal as drug delivery system for overcoming the biological barrier of cyano-phycocyanin: a biomedical application of microbial product

ABSTRACTPhycocyanin, produced by Spirulina platensis, has been reported as an anti-inflammatory, anti-hyperalgesia, antioxidant, anti-tumor, and anti-cancer agent. However, the ingestion of phycocyanin in the body is often hindered by its instability against gastric pH conditions. The nano-drug delivery system has developed as a promising platform for efficient drug delivery and improvement as well as drug efficacy. Bacterial cellulose nanocrystal (BCNC) has it superiority as DDS due to its inherent properties such as nanoscale dimension, large surface area, - biocompatibility, and non-toxic. To improve its mechanical properties, BCNC was crosslinked with glutaraldehyde and was analyzed as a potential candidate for DDS. The Fourier transform infrared analysis of the BCNC suggested that hydrolysis did not alter the chemical composition. The index of crystallinity of the BCNC was 18.31% higher than that of the original BC, suggesting that crystalline BC has been successfully isolated. The BCNC particle also showed a needle-like morphology which is 25 ± 10 nm in diameter and a mean length of 626 ± 172 nm. Crosslinked BCNC also had larger pores than the original BCNC along with higher thermal stability. Optimum phycocyanin adsorption on crosslinked BCNC reached 65.3% in 3 h. The release study shows that the crosslinked BCNC can protect the phycocyanin retardation by gastric fluid until phycocyanin reaches the targeted sites. This study provides an alternative potential DDS derived from natural bioresources with less expenses and better properties to promote the application of BCNC as functional nanomaterials in biomedical science.

A green versatile packaging based on alginate and anthocyanin via incorporating bacterial cellulose nanocrystal-stabilized camellia oil Pickering emulsions

This study aims to develop a versatile intelligent packaging based on alginate (Alg) and anthocyanin (Ant) by incorporating bacterial cellulose nanocrystal-stabilized camellia oil Pickering emulsions. Firstly, bacterial cellulose nanocrystals (BCNs) matrix produced from kombucha was incorporated with camellia oil into via ultrasonic triggering, forming a stable and multifunctional camellia oil-bacterial cellulose nanocrystal Pickering nanoemulsions (CBPE). The microstructure and rheology results of the emulsion confirmed the stabilized preparation of CBPE. Subsequently, the CBPE was integrated into the three-dimensional network structure composed of alginate/anthocyanin. The composite film (Alg-Ant-CBPE) was designed through Ca2+ crosslinking, intermolecular hydrogen bonding and dehydration condensation. The fabricated color indicator films with different concentrations of CBPE (0.1 %–0.4 %), showed varying degree of improvement in hydrophobicity, UV shielding, mechanical strength, thermal stability, water vapor barrier properties and antioxidant capacities. When applied to yogurt, the Alg-Ant-CBPE4 exhibited more pronounced color changes compared to Alg-Ant, enabling visual detection of food freshness. In conclusion, the incorporation of Pickering nanoemulsion provides an effective and promising approach to enhance the performance of polysaccharide-based intelligent packaging.

Cinnamon Essential-Oil-Loaded Fish Gelatin–Cellulose Nanocrystal Films Prepared under Acidic Conditions

The aim of this study was to characterize films obtained from fish gelatin (GelA, 3% w/w), encapsulated with cinnamon essential oil (CEO, 0.03–0.48% v/w), and loaded with bacterial cellulose nanocrystals (BCNCs, 0.06% w/w) at pH = 3.5. CEO-GelA/BCNC films were prepared by casting, and thickness, light transmittance (TT) and haze (H), surface hydrophobicity, tensile properties, chemical composition, and water solubility (WS) thereof were assessed. All films displayed outstanding optical properties (TT > 89.4%), with haze slightly exceeding a 3% value only at the highest CEO loading within the nanoemulsion formulation. The CEO plasticizing effect increased the elongation at break (EAB, from 0.84% up to 3.79%) and decreased the tensile strength (TS, from 8.98 MPa down to 1.93 MPa). The FT-IR spectra of films revealed good interaction among nanoemulsion components via hydrogen bonding. The CEO hydrophobic nature negatively impacted the WS (from 52.08% down to 8.48%) of the films. The results of this work confirmed the possibility of producing packaging systems from renewable sources to be potentially used in the form of edible films/coatings for the preservation of water-sensitive food products, both vegan-based (fruits/vegetables) and animal-based (meat/seafood).

Bacterial cellulose vs. bacterial cellulose nanocrystals as stabilizer agents for O/W pickering emulsions

The growing interest in Pickering emulsions in functional food systems resulted in the need to find suitable stabilizers for them. The work considers the use of bacterial cellulose for this purpose, and its aim was to compare the properties of disintegrated bacterial cellulose, before and after freeze-drying, and its nanocrystals obtained using H2SO4 under variable of time and concentration conditions. The structure of nanocrystals obtained with 30% acid was found to be still similar to that of parent cellulose, while the structure of nanocrystals obtained with 65% acid showed allomorphic transformation and the cellulose sulfates formation, regardless of the acid treatment time. Unlike nanocrystals obtained with 65% acid, those obtained with 30% acid as well as native bacterial cellulose ensured the high stability of O/W emulsion containing up to 20% olive oil. Effective stabilization of emulsions with the addition of nanocrystals obtained with the use of 30% acid was ensured by their strong surface charge density due to the presence of negatively charged sulfate groups.

Multifunctional sustainable films of bacterial cellulose nanocrystal-based, three-phase pickering nanoemulsions: A promising active food packaging for cheese

Owing to increasing plastic pollution and concerns about food safety, extensive research attention has been paid to biodegradable active packaging. Herein, we developed bacterial cellulose nanocrystal (BCN)-based three-phase Pickering nanoemulsion gelatin (GL) films. In detail, bacterial cellulose was obtained using Acetobacter xylinum, which was then hydrolyzed using sulfuric acid to prepare BCNs. Carnosic acid (CA) and ε-polylysine (εPL) were incorporated into the BCN matrix through electrostatic complexation and the matrix was ultrasonically triggered as an emulsification self-assembly strategy, forming the multifunctional BCN-based three-phase O/W Pickering nanoemulsions (CA-εPL PEs). Furthermore, a novel active packaging film (GL-CA-εPL PEs) was designed via intermolecular hydrogen bonding and dehydration condensation by introducing CA-εPL PEs into the 3D network structures of a GL matrix; both phases showed good interaction and compatibility, along with excellent antioxidant, antibacterial, UV-shielding, good mechanical, heat-sealing, sustainable release, and biodegradable properties. Additionally, fresh (acid-coagulated) and mozzarella cheese were packed in the GL-CA-εPL100 PE film, and their shelf life was extended due to delayed lipid peroxidation and inhibition of the growth of spoilage microorganisms. Sensorial and flavored (GC-IMS) analyses showed no significant differences between the samples packed in the GL-CA-εPL100 PE active film and the unpacked samples. This study provides scientific insights for designing BCN-based O/W multifunctional three-phase Pickering nanoemulsion delivery systems for active food packaging; the proposed method can be promising for reducing the environmental impact of plastic pollution.

Bacterial cellulose nanocrystals with a great difference in aspect ratios: A comparison study of their reinforcing effects on properties of the sodium alginate film

Cellulose nanocrystal (CNC) incorporation is a practical way to improve the properties of polysaccharide films, and the aspect ratio (L/D) of CNC is a crucial morphological factor affecting its reinforcing effects. In this study, the changes in properties of sodium alginate (SA) films with bacterial CNCs (BCNCs) of great L/D differences were tested and the Young's modulus (E) results of films were compared with predictions from the Halpin–Kardos and Ouali models. At BCNC concentrations ≤0.5 wt%, BCNCs with L/D of 91.45 (BCNC91) and 130.31 (BCNC130) were more effective in reinforcing E than BCNC with L/D of 41.04 (BCNC41). Because AFM and FTIR results confirmed that at this stage, all three BCNCs were well-dispersed, but BCNC91 and BCNC130 formed more new hydrogen bonds with SA than BCNC41. Further increasing BCNC concentrations to 1 wt%–3 wt% continued to enhance E but all BCNCs' reinforcing efficiencies decreased in sync with the formation of BCNC percolation networks and aggregations until efficiency disparities of three BCNCs diminished with all SA-BCNC films' E at around 1800 MPa. The fact that the Halpin–Kardos model described E better than the filler-network-based Ouali model, but still seriously underestimated E at BCNC concentrations ≤3 wt%, was attributed to the greater interfacial area effect produced by nanosized BCNCs than that of the macro-fibers used to develop the Halpin–Kardos model and emphasized the importance of SA-BCNC interactions. Moreover, BCNCs with higher L/D required lower concentrations to significantly reduce films' water vapor permeabilities, and nanocomposites with BCNC130 were more transparent but less UV-light resistant than others.

Acid-derived bacterial cellulose nanocrystals as organic filler for the generation of high-oxygen barrier bio-nanocomposite coatings

This study investigates the effect of the hydrolysis process on bacterial cellulose (BC) to obtain bacterial cellulose nanocrystals (BCNCs) used to create high oxygen barrier nanocomposite coatings for food packaging applications.

Development of asphalt cements for road pavement using sustainable nanomaterials: A review

AbstractIn today's world, transportation infrastructure plays a vital role in global competitiveness and quality of life in societies. The pavement industry deals with tremendous amounts of construction materials. Thus, even a small improvement in the technology can lead to significant environmental benefits and a reduction in the life‐cycle cost of road networks. Asphalt cement is an integral part of road pavement construction, and despite favorable properties at the processing temperature, some challenges need to be addressed to reduce cost and improve performance. This review discusses the nanocellulose modification of asphalt cement for pavement application. Three primary cellulose‐based nanoparticles were studied, including bacterial cellulose, cellulose nanofibers, and cellulose nanocrystals, and their applications in asphalt cement modification. Various research results show significant improvement in pavement's rheological and performance properties with the help of cellulose‐based nanoparticles. However, this review provides the reader with an objective evaluation of the benefits and practical challenges ahead of the industrial‐scale application of nanocellulose in the pavement industry.

Alginate films as carriers of probiotic bacteria and Pickering emulsion

Bioactive edible films have been proposed from a calcium-crosslinked alginate matrix added with probiotic bacteria (Bacillus coagulans, as the bioactive component) and/or bacterial cellulose nanocrystal (BCNC)-stabilized palm olein Pickering emulsion (as a hydrophobizing component). The emulsion, however, instead of increasing the surface hydrophobicity and the barrier to water vapor, decreased both, due to discontinuities on the film structure and possibly the BCNC layer around the droplets minimizing the surface exposure of the hydrophobic phase (and its effects on film hydrophobicity). The probiotic bacteria, on the other hand, besides increasing the elastic modulus (which was ascribed to electrostatic interactions between teichoic acid and calcium), also enhanced both surface hydrophobicity and barrier to water vapor, probably due to the hydrophobicity of Bacillus spores. The probiotics exhibited high viability (> 8 log cfu.g−1, on a dry film basis) during film drying, storage, and digestion in a simulated gastrointestinal tract.

Nano-cellulose Reinforced Glass Ionomer Restorations: An In Vitro study

ObjectiveVarious modifications in formulation of glass ionomer cements (GICs) have been made in order to improve the clinical performance of these restorations. The aim of this work was to evaluate the microleakage and microshear bond strength (μSBS) of bacterial cellulose nanocrystal (BCNC)–modified glass ionomer cement (GIC) restorations in primary dentition. MethodsA total number of 60 freshly extracted primary molar teeth were selected. Half of the samples were used for μSBS testing (in 2 groups, n = 15). In group 1, conventional GIC (CGIC) of Fuji IX (GC) was placed in cylindrical molds on dentinal surfaces. In group 2, CGIC of Fuji IX containing 1% wt of BCNCs was used. μSBS was evaluated using a universal testing machine. In another part of the study, microleakage of class V restorations was assessed according to the mentioned groups (n = 15). The sectioned samples were observed under stereomicroscope, and microleakage scores were recorded. SPSS version 16.0 (SPSS), independent samples t test, and Mann–Whitney U test were used for statistical analysis at a significance level of P < .05. ResultsResults showed statistically significant differences between the μSBS of CGIC and modified GIC groups (P < .0001). The BCNC-modified GIC group recorded significantly higher bond strength values (3.51 ± 0.033 vs 1.38 ± 0.034 MPa). Also, microleakage scores of CGIC and BCNC-modified GIC restorations were not significantly different (P = .57). ConclusionsBased on our findings, it was concluded that incorporating BCNCs (1% wt) into the CGIC of Fuji IX significantly increased the μSBS to the dentin structure of the primary teeth.

Tracking Bacterial Nanocellulose in Animal Tissues by Fluorescence Microscopy.

The potential of nanomaterials in food technology is nowadays well-established. However, their commercial use requires a careful risk assessment, in particular concerning the fate of nanomaterials in the human body. Bacterial nanocellulose (BNC), a nanofibrillar polysaccharide, has been used as a food product for many years in Asia. However, given its nano-character, several toxicological studies must be performed, according to the European Food Safety Agency’s guidance. Those should especially answer the question of whether nanoparticulate cellulose is absorbed in the gastrointestinal tract. This raises the need to develop a screening technique capable of detecting isolated nanosized particles in biological tissues. Herein, the potential of a cellulose-binding module fused to a green fluorescent protein (GFP–CBM) to detect single bacterial cellulose nanocrystals (BCNC) obtained by acid hydrolysis was assessed. Adsorption studies were performed to characterize the interaction of GFP–CBM with BNC and BCNC. Correlative electron light microscopy was used to demonstrate that isolated BCNC may be detected by fluorescence microscopy. The uptake of BCNC by macrophages was also assessed. Finally, an exploratory 21-day repeated-dose study was performed, wherein Wistar rats were fed daily with BNC. The presence of BNC or BCNC throughout the GIT was observed only in the intestinal lumen, suggesting that cellulose particles were not absorbed. While a more comprehensive toxicological study is necessary, these results strengthen the idea that BNC can be considered a safe food additive.

Production of Innovative Essential Oil-Based Emulsion Coatings for Fungal Growth Control on Postharvest Fruits.

This work assessed the antimicrobial potential of natural essential oils (EOs) from cinnamon (CEO), zataria (ZEO), and satureja (SEO), applied natively or as coatings against Penicillium expansum and Botrytis cinerea during both in vitro and in vivo (on apple fruits) experiments. The induced inhibitory effect towards fungal growth, as a function of both EO type and concentration (75–1200 μL/L), was preliminarily investigated to select the most suitable EO for producing bacterial cellulose nanocrystals (BCNCs)/fish gelatin (GelA)-based emulsions. CEO and ZEO exhibited the best performances against P. expansum and B. cinerea, respectively. None of the pristine EOs completely inhibited the fungal growth and “disease severity”, properly quantified via size measurements of lesions formed on fruit surfaces. As compared to pristine CEO, coating emulsions with variable CEO concentration (75–2400 µL/L) curbed lesion spreading on apples, owing to the controlled CEO release during a 21-day temporal window. The strongest effect was displayed by BCNCs/GelA-CEO emulsions at the highest CEO concentration, upon which lesions on fruit skins were barely detectable. This work demonstrated the capability of EOs embedded in BCNCs/GelA-based nanocapsules to efficiently slow down microbial spoilage on postharvest fruits, thus offering viable opportunities for developing innovative antimicrobial packaging systems.

Impact of Bacterial Cellulose Nanocrystals-Gelatin/Cinnamon Essential Oil Emulsion Coatings on the Quality Attributes of ‘Red Delicious’ Apples

This study aimed to assess the effectiveness of bacterial cellulose nanocrystals (BCNCs)-gelatin (GelA)/cinnamon essential oil (CEO) emulsion coatings containing various CEO concentrations (1200, 1800, and 2400 μL/L) in retarding ripening and senescence of ‘Red Delicious’ apples during cold storage (60 days at 4 °C). Coatings decreased the weight loss (WL) (~3.6%), as compared to uncoated fruit (~4.8%). A direct relationship between CEO concentration and respiration rate/ethylene production was also disclosed. Flesh firmness was higher for coated samples, with better results detected especially when the highest amount of CEO was applied (36.48 N for the 2400 μL/L delivered dose vs. 32.60 N for the 1200 μL/L one). These findings were corroborated by additional tests on the surface color, total acidity, soluble solids content, pH, ascorbic acid, and activities of polyphenol oxidase (PPO) and peroxidase (POD). This study demonstrated the capability of BCNCs-GelA/CEO systems to dramatically enhance the storability and quality of apples during refrigerated storage, thus avoiding undesired losses and increasing the economic performance of fresh fruit industries.

Fabrication of Noncytotoxic Functional Siloxane-Coated Bacterial Cellulose Nanocrystals

Bacterial cellulose nanocrystals (BCNC) stand out as versatile biocolloidal building blocks for materials that are high-performance, owing to their inherently high crystallinity and specific modulus and surface area, and sustainable, as BCNC are both biobased and biodegradable. BCNC materials are also promising for their multifunctionality because of their huge potential to undergo physical and/or chemical surface modification. This is particularly appealing for biomedical applications thanks to the biocompatibility, high purity, and low toxicity of BCNC. We report on films based on surface-modified BCNC with varying contents of 3-glycidyloxypropyltrimethoxysilane (GPTMS) or 3-aminopropyltriethoxysilane (APTS). Importantly, these highly pure and crystalline needle-shaped BCNC were isolated from scraps generated at industrial operations when shaping bacterial cellulose membranes into wound dressings. The films were extensively characterized as far as their structural characteristics, with emphasis on the major features targeting at biological applications. Compared with pristine BCNC, the films performed better from the thermal stability standpoint and maintained the noncytotoxicity against nontransforming fibroblasts. The latter claim was independent of GPTMS content, but dose-dependent for APTS and valid for films containing up to 30% of this coupling agent. Altogether, this contribution expands the wingspan of nanocellulose-based materials in biomedical applications while mitigating the waste of natural resources by upcycling an industrial byproduct, falling within the circular bioeconomy framework.

Evaluation of the water-holding and anti-spoilage effect of a bacterial cellulose nanocrystal coating for the storage of vacuum-packaged beef

The preservative effect of applying bacterial cellulose nanocrystals (BCNs) and nisin-loaded BCNs (NBCNs) as spray coatings for vacuum-packaged beef was investigated and compared to uncoated beef for up to 4 weeks. The impact of nanocoatings on water-holding properties was investigated using purge loss, drip loss and LF NMR analysis. Physicochemical, microbiological and sensory properties were also performed to analyse the anti-spoilage effect of the coatings. The electrochemical interaction between nanocrystals and the meat structure was evaluated by Kelvin probe force microscopy and zeta-potential analysis. BCNs alone significantly increased the microbial growth while treating beef with NBCNs reduced bacterial growth. No significant impact of nanocrystals on physicochemical and sensorial properties was observed. Nanocrystals were not effective in controlling purge loss. This study suggests that weak electrochemical interaction between nanocrystals and purge may relate to poor water-holding properties and this could aid in the design of new preservative coatings using nanocrystals.