Cellulose Pellicles Research Articles

TEMPO-Oxidized Bacterial Cellulose Pellicle with Silver Nanoparticles for Wound Dressing.

Biocompatible bacterial cellulose pellicle (BCP) is a candidate for biomedical material such as wound dressing. However, due to lack of antibacterial activity, to grant BCP with the property is crucial for its biomedical application. In the present study, BCP was modified by 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-mediated oxidation using TEMPO/NaClO/NaBr system at pH 10 to form TEMPO-oxidized BCP (TOBCP) with anionic C6 carboxylate groups. The TOBCP was subsequently ion-exchanged in AgNO3 solution and silver nanoparticles (AgNP) with diameter of ∼16.5 nm were in situ synthesized on TOBC nanofiber surfaces by thermal reduction without using a reducing agent. Field emission scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectra, Fourier transform infrared spectroscopy, and thermogravimetric analysis were carried out to confirm morphology and structure of the pellicles with AgNP. The AgNP continuously released Ag+ with a rate of 12.2%/day at 37 °C in 3 days. The TOBCP/AgNP exhibited high biocompatibility according to the result of in vitro cytotoxicity test (cell viability >95% after 48 h of incubation) and showed significant antibacterial activities of 100% and 99.2% against E. coli and S. aureus, respectively. Hence, the highly biocompatible and highly antibacterial TOBCP/AgNP prepared in the present study is a promising candidate for wound dressing.

Enhanced bacterial cellulose production from Gluconobacter xylinus using super optimal broth

The bacterial cellulose (BC) produced by Gluconobacter xylinus due to its versatile properties, is used in healthcare and industrial applications. However, its use is restricted owing to the limited yield from the existing culture protocols. In the current study, BC production is studied in the presence of Super Optimal Broth with catabolite repression (SOC) medium which is used to revive Escherichia coli cells after electroporation or chemoporation. In SOC medium, Gluconobacter xylinus produces cellulose pellicles within 5 days of incubation with an enhanced conversion of the carbon source to cellulose compared to traditional Hestrin–Schramm (HS) medium. SOC medium also maintains the pH close to 7.0 in static cultures unlike in HS medium where the pH is acidic. The physico-chemical and morphological characteristics of the BC produced in SOC are determined using powder X-ray diffraction (pXRD), thermo gravimetric analysis (TGA), Brunauer–Emmett–Teller (BET) and Barrett–Joyner–Halenda (BJH), and scanning electron microscopy (SEM) analyses. Our results indicate that SOC enhance the yield of bacterial cellulose and allows conversion of 50% of the carbon source to bacterial cellulose, compared to only 7% conversion in the case of traditional HS medium after 7 days of interaction. We also observe an increase in hydration capacity of BC produced using SOC as compared to HS media.

Effects of Collagen Concentration Variation toward Characteristics of Bacterial Cellulose-Collagen Biocomposites as Candidate of Artificial Dura Mater

Traffic accident is the highest cause of head injury. In the field of neurosurgery, it is closely related to the defect of duramater (outer layer of the brain). This study aims to perform artificial duramater synthesis from bacteria cellulose that is composited with collagen in order to find the precise composition. Bacteria cellulose was synthesized by fertilizing Acetobacter xylinum bacteria into coconut water. In addition, bacteria cellulose pellicle membrane immersed into collagen solution with various concentration such as 0.4% w/v, 0.5% w/v, 0.6% w/v and 0.7% w/v. The dried sample was characterized by Fourier Transform Infra Red (FTIR), tensile tester, Scanning Electron Microscope (SEM) and swelling test procedure. Result showed that the best sample was ‘Sample A’ (bacteria cellulose-collagen 0.4% w/v) that obtained 8% elongation and 185 μm for the average thickness. Based on the entire result, the biocomposite of bacteria celluose-collagen has a high potential as a candidate of artificial duramater.

Nanocelluloses obtained by ammonium persulfate (APS) oxidation of bleached kraft pulp (BKP) and bacterial cellulose (BC) and their application in biocomposite films together with chitosan

Abstract Bleached birch kraft pulp (BKP, Södra Cell AB, Sweden) and unmodified bacterial cellulose (BC) pellicles, biosynthesized by the bacterium Komagataeibacter rhaeticus, were converted to cellulose nanofibers via ammonium persulfate (APS) oxidation. Fiber dimensions were investigated in an atomic force microscope, and the crystallite size was calculated by Rietveld analysis. Saos-2 osteosarcoma cell line served to assess the in vitro cytocompatibility of the biocomposite films. Results showed that individual cellulose nanofibers with an average width of 80±15 nm and a length between 600 and 1200 nm are formed by APS oxidation. The obtained BC nanofibers can be promising constituents in nanocellulose films and in chitosan-matrix films with improved physical-mechanical and biological properties. Good cellular biocompatibility was found for chitosan/oxidized cellulose films; the viability of Saos-2 osteosarcoma cells was higher on chitosan/oxidized BC films compared to chitosan/oxidized BKP films.

Bacterial Nano‐Cellulose Triboelectric Nanogenerator

Motivated by a desire to resolve the needs of sustainable energy resources, remote sensing electronics, wireless autonomous devices, mobile internet of things (IoT) and portable self-power generators, triboelectric nanogenerators have recently been suggested. However, more specialized target applications to biomedical and wearable devices will require biocompatible and eco-friendly triboelectric materials in power generators. Herein, we report for the first time a bio-triboelectric nanogenerator based on an eco-friendly and naturally abundant biomaterial, bacterial nanocellulose. Initially, bacterial cellulose pellicles were produced in a gel state by Acetobacter xylinum KJ1 in the Glu-Fruc medium and then a bacterial nanocellulose film having transparent and flexible functionalities was regenerated on a current collector via a solubilization process. The bacterial nanocellulose triboelectric nanogenerator was investigated with various input conditions and structural aspects. The working mechanism was also considered by measuring the contact angle and the surface potential of the friction materials. We believe that this study provides new insights to advancing the biocompatible and eco-friendly triboelectric power generator and optimization strategies to achieve high performance of triboelectric nanogenerators.

Synthesis and Characterization of Bacterial Cellulose - <i>Garcinia mangostana</i> Extract as Anti Breast Cancer Biofilm Candidate

In Indonesia, breast cancer is noted as the most common cancer in women. Accordingly, this research was conducted to synthesize biofilm from bacterial cellulose by adding ethanol extract of mangosteen peel. The pellicle of bacterial cellulose was soaked in a 100 mL ethanol solution of mangosteen peel extract varied by 0.5%, 1%, 1.5%, and 2% v/v. The samples were characterized using the SEM, FTIR, and MTT Assay using the T47D breast cancer cells. The results using the SEM showed the thickness of the bacterial cellulose biofilm samples was 5.63 μm, while the 2% v/v thickness of the bacterial cellulose of the extract of mangosteen peel biofilm samples was 12.2 μm. The FTIR results showed a weak interaction between the O-H groups of the microbial cellulose and the C=C functional group in the phenolic compounds of the mangosteen peel extract. Based on the MTT Assay test results using the T47D breast cancer cells, the highest percentage of cell death result was 25.47% on the 2% v/v bacterial cellulose of the mangosteen peel extract samples. The Garcinia mangostana extracts added in the bacterial cellulose biofilms still required optimal concentrations in order to become potential killing mechanism for the T47D breast cancer cells.

Nanocellulose based asymmetric composite membrane for the multiple functions in cell encapsulation

We describe the nanocomposite membrane for cell encapsulation using nanocelluose hydrogels. One of the surfaces of bacterial cellulose (BC) pellicles was coated with collagen to enhance cell adhesion and the opposite side of the BC pellicles was coated with alginate to protect transplanted cells from immune rejection by the reduced pore size of the composite membrane. The morphology of nanocomposite membrane was observed by scanning electron microscopy and the permeability of the membrane was estimated by the release test using different molecular weights of polymer solution. The nanocomposite membrane was permeable to small molecules but impermeable to large molecules such as IgG antibodies inferring the potential use in cell implantation. In addition, the BC-based nanocomposite membrane showed a superior mechanical property due to the incorporation of compared with alginate membranes. The cells attached efficiently to the surface of BC composite membranes with a high level of cell viability as well as bioactivity. Cells grown on the BC composite membrane kit released dopamine freely to the medium through the membrane, which showed that the BC composite membrane would be a promising cell encapsulation material in implantation.

Utilizing the Ethylene-releasing Compound, 2-Chloroethylphosphonic Acid, as a Tool to Study Ethylene Response in Bacteria.

Ethylene (C2H4) is a gaseous phytohormone that is involved in numerous aspects of plant development, playing a dominant role in senescence and fruit ripening. Exogenous ethylene applied during early plant development triggers the triple response phenotype; a shorter and thicker hypocotyl with an exaggerated apical hook. Despite the intimate relationship between plants and bacteria, the effect of exogenous ethylene on bacteria has been greatly overlooked. This is partly due to the difficulty of controlling gaseous ethylene within the laboratory without specialized equipment. 2-Chloroethylphosphonic acid (CEPA) is a compound that decomposes into ethylene, chlorine, and phosphate in a 1:1:1:1 molar ratio when dissolved in an aqueous medium of pH 3.5 or greater. Here we describe the use of CEPA to produce in situ ethylene for the investigation of ethylene response in bacteria using the fruit-associated, cellulose-producing bacterium Komagataeibacter xylinus as a model organism. The protocols described herein include both the verification of ethylene production from CEPA via the Arabidopsis thaliana triple response assay and the effects of exogenous ethylene on K. xylinus cellulose production, pellicle properties and colonial morphology. These protocols can be adapted to examine the effect of ethylene on other microbes using appropriate growth media and phenotype analyses. The use of CEPA provides researchers with a simple and efficient alternative to pure ethylene gas for the routine determination of bacterial ethylene response.

Preparation of bacterial cellulose/carbon nanotube nanocomposite for biological fuel cell

In this study, electrically conducting composite membranes were prepared by incorporating carboxylic multi-walled carbon nanotubes (c-MWCNTs) into Bacterial Cellulose (BC) pellicles. The biocathode and bioanode were prepared by a simple method of adsorption. An enzyme biological fuel cell (EBFC) composed of a biocathode and an enzymatic bioanode were developed and tested. The materials was characterised by field emission scanning electron microscope (FESEM), Fourier Transform Infrared (FTIR) Spectroscopy and Thermogravimetric analysis (TGA). The results showed that the presence of c-MWCNTs on BC was certified, on which c-MWCNTs loading was calculated as 30.02/100 g. The BC/c-MWCNTs/Lac composite membranes was characterized by cyclic voltammetry (CV). An EBFC was characterized by linear sweep voltammetry (LSV). The results showed EBFC exhibited excellent performance with the largest open circuit voltage (0.76 V) and a maximum power density value (55 uW/cm3). Additionally, the cell also exhibited acceptable stability over the recording of 30 days. BC was considered to be suitable for advanced applications such as an enzymatic carrier of biological fuel cells.

Direct Synthesis of Bacteria-Derived Carbonaceous Nanofibers as a Highly Efficient Material for Radionuclides Elimination

Bacteria-derived carbonaceous nanofibers (CNFs) can be directly synthesized by the pyrolysis of bacterial cellulose pellicles under N2 atmosphere. The batch adsorption experiments showed that the bacteria-derived CNFs displayed the excellent adsorption performance for radionuclides. The maximum adsorption capacities of the CNFs calculated from the Langmuir model at pH 4.5 and 293 K were 67.11 mg/g for Sr(II) and 57.47 mg/g for Cs(I). The adsorption of Cs(I) and Sr(II) on the CNFs decreased with increasing ionic strength at pH 6.0, indicating that the outer-sphere surface complexation dominated the radionuclide adsorption at pH 6.0. The further evidence of surface complexation modeling indicated that Sr(II) and Cs(I) adsorption on the CNFs can be satisfactorily fitted by a double diffuse layer model with an outer-sphere (SOHSr2+/SOHCs+) and an inner-sphere...

Natural Self-grown Fashion From Bacterial Cellulose: A Paradigm Shift Design Approach In Fashion Creation

The fashion industry is regarded as responsible for causing soil erosion, water pollution, and large-scale carbon dioxide emissions and waste because of the many production processes it involves. This paper reports on a study that explored the concept of future fashion, which uses materials that grow directly from natural and renewable sources (i.e. biofashion from bacterial cellulose). In this study, various types of bacterial cellulose were studied and evaluated. Green tea cellulose was identified as the most desirable for fashion creation. The cellulosic pellicles of green tea grown in various culture solution concentrations and incubation times were compared for an optimal result. A theoretical and practical framework was established to explore bacterial cellulose for use in fashion creation. Successful realization of natural self-grown fashion (SGF) has tremendous creative and practical potential, as well as a profound ecological effect on the fashion industry and the environment.

Fabrication of bacterial cellulose-ZnO composite via solution plasma process for antibacterial applications

Zinc oxide (ZnO) was successfully synthesized by applying a solution plasma, a plasma discharge in a liquid phase, without the addition of a reducing agent and simultaneously deposited into a bacterial cellulose pellicle that functioned as a template. By the reasons of its nano-sized structure as well as favorable porous configuration, the BC pellicle has been proved to be a splendid upholding template for the coordination of ZnO. In addition, the ZnO-deposited BC composites demonstrated strong antibacterial activity without a photocatalytic reaction against both Staphylococcus aureus and Escherichia coli. Hence, the ZnO-deposited BC composites can be used as an antibacterial material in wound dressing and water disinfection applications.

Rice Straw Cellulose Nanofibrils via Aqueous Counter Collision and Differential Centrifugation and Their Self-Assembled Structures

Rice straw cellulose was completely defibrillated via aqueous counter collision (ACC) at a low energy input of 15 kWh/kg, then fractionated by differential centrifugation into four increasing weight fractions of progressively thinner cellulose nanofibrils (CNFs): 6.9% in 80–200 nm, 14.4% in 20–80 nm, 20.3% in 5–20 nm, and 58.4% in less than 5 nm thickness. The 93.1% less than 80 nm or 78.7% less than 20 nm thick CNFs yields were more than double those from wood pulp by other mechanical means but at a lower energy input. The smallest (3.7 nm thick and 5.5 nm wide) CNFs were only a third or less in lateral dimensions than those obatined through ACC processed from wood pulp, bamboo, and microbial cellulose pellicle. The less than 20 nm thick CNFs could self-assemble into continuous submicron (136 nm) wide fibers by freezing and freeze-drying or semitransparent (13–42% optical transmittance) film by ultrafiltration and air-drying with excellent mechanical properties (164 MPa tensile strength, 4 GPa Young’s mo...

Bio-based nanomaterials–versatile materials for industrial and biomedical applications

In this work, unmodified bacterial cellulose pellicles, biosynthesized by the bacterium Komagataeibacter rhaeticus, bleached birch Kraft pulp (Södra Cell AB, Sweden) and birch bark supplied by the plywood industry (JSC Latvijas Finieris, Latvia), were used to obtain the nanoparticles. The results showed that cellulose nanoparticles fabricated by the ammonium persulfate oxidation method, an alternative method developed at the Latvian State Institute of Wood Chemistry, are promising constituents for producing nanopaper. Cellulose and birch bark nanofillers show the potential to improve the physical-mechanical and biological properties of chitosan-matrix films.

Analysis of Bacterial Cellulose/Ionic Liquid MWCNTs via Cyclic Voltammetry

Cyclic voltammetry based on an electrochemical technique is one of the current methods that measure the developments of the electrochemical properties in biomaterial samples under conditions. Biomaterial structure was changed by conductive material while these materials caused a connective network in whole of them and was able to transfer electrons inside of biomaterials. These changes in physical and chemical properties are investigated by analysis tools such as cyclic voltammetry (CV), X-radiation (XRF) and Ultraviolet-visible spectroscopy (UV-Vis). Bacterial cellulose is biodegradable, biosynthesis of A. xylinum which is a three-dimensional nano-network structure with a distinct tunnel and pore structure. In this study, the composite process produced electrically conducting bacterial cellulose pellicles containing well-dispersed and embedded multi-walled carbon nanotubes (MWCNTs) Ionic liquids (ILs), as observed in cyclic voltammetry (CV). For this purpose, we used a special tool, called OriginLab which is an industry-leading scientific graphing and data analysis software. The cyclic voltammetry graph presents the behavior of this composite which consists of a relationship between CNT dispersion, conductivity rate and changes in bacterial cellulose structure. The electrical conductivity of the cellulose/MWCNT composite was found different with respect to CNT dispersion. It was found that the incorporation process was a useful method not only for dispersing MWCNTs-ILs in an ultrafine fibrous network structure, but also for enhancing the electrical conductivity of the polymeric membranes.

A Study of the Receptivity to Bacterial Cellulosic Pellicle for Fashion

Over the past few decades, there have been an increasing number of attempts to produce materials for fashion creation aiming at cost effectiveness, low environmental impact, labour friendliness and biodegradability. Among them, biotechnology is believed to be one of the finest substitutes for future fashion creation. A study has been carried out to explore the future development of fashion design and the possible applications of materials which can be grown from natural renewable and degradable resources. A pilot test with five design professionals on the comfort of bacterial cellulosic pellicles produced in varied incubation times and broth concentrations was conducted. This paper reports a further investigation of the receptivity to these bacterial cellulosic pellicles as material for future fashion through comparing and evaluating three comfort factors, namely hand comfort, flexibility comfort and breathability comfort, and two appearance factors, namely colour and texture, with 150 subjects using the random sampling method. The optimal favourable pellicle for fashion creation was identified and presented.

In Vivo Curdlan/Cellulose Bionanocomposite Synthesis by Genetically Modified Gluconacetobacter xylinus.

Bacterial cellulose pellicle produced by Gluconacetobacter xylinus (G. xylinus) is one of the best biobased materials having a unique supernetwork structure with remarkable physiochemical properties for a wide range of medical and tissue-engineering applications. It is still necessary to modify them to obtain materials suitable for biomedical use with satisfactory mechanical strength, biodegradability, and bioactivity. The aim of this research was to develop a gene-transformation route for the production of bacterial cellulose/Curdlan (β-1,3-glucan) nanocomposites by separate but simultaneous in vivo synthesis of cellulose and Curdlan. Modification of the cellulose-nanofiber-producing system of G. xylinus enabled Curdlan to be synthesized simultaneously with cellulose nanofibers in vivo, resulting in biopreparation of nanocomposites. The obtained Curdlan/cellulose composites were characterized, and their properties were compared with those of normal bacterial cellulose pellicles, indicating that Curdlan mixed with the cellulose nanofibers at the nanoscale without disruption of the nanofiber network structure in the pellicle.

Modification of bacterial cellulose through exposure to the rotating magnetic field

The aim of the study was to assess the influence of rotating magnetic field (RMF) on production rate and quality parameters of bacterial cellulose synthetized by Glucanacetobacter xylinus. Bacterial cultures were exposed to RMF (frequency f=50Hz, magnetic induction B=34mT) for 72h at 28°C. The study revealed that cellulose obtained under RMF influence displayed higher water absorption, lower density and less interassociated microfibrils comparing to unexposed control. The application of RMF significantly increased the amount of obtained wet cellulose pellicles but decreased the weight and thickness of dry cellulose. Summarizing, the exposure of cellulose-synthesizing G. xylinus to RMF alters cellulose biogenesis and may offer a new biotechnological tool to control this process. As RMF-modified cellulose displays better absorbing properties comparing to non-modified cellulose, our finding, if developed, may find application in the production of dressings for highly exudative wounds.

Cellulose produced by Gluconacetobacter xylinus strains ATCC 53524 and ATCC 23768: Pellicle formation, post-synthesis aggregation and fiber density

The pellicle formation, crystallinity, and bundling of cellulose microfibrils produced by bacterium Gluconacetobacter xylinus were studied. Cellulose pellicles were produced by two strains (ATCC 53524 and ATCC 23769) for 1 and 7 days; pellicles were analyzed with scanning electron microscopy (SEM), X-ray diffraction (XRD), vibrational sum-frequency-generation (SFG) spectroscopy, and attenuated total reflectance infrared (ATR-IR) spectroscopy. The bacterial cell population was higher at the surface exposed to air, indicating that the newly synthesized cellulose is deposited at the top of the pellicle. XRD, ATR-IR, and SFG analyses found no significant changes in the cellulose crystallinity, crystal size or polymorphic distribution with the culture time. However, SEM and SFG analyses revealed cellulose macrofibrils produced for 7 days had a higher packing density at the top of the pellicle, compared to the bottom. These findings suggest that the physical properties of cellulose microfibrils are different locally within the bacterial pellicles.

Structural modification and characterization of bacterial cellulose–alginate composite scaffolds for tissue engineering

A novel bacterial cellulose–alginate composite scaffold (N-BCA) was fabricated by freeze drying and subsequent crosslinking with Ca2+. The N-BCA then underwent a second freeze drying step to remove water without altering the physical structure. A stable structure of N-BCA with open and highly interconnected pores in the range of 90–160μm was constructed. The N-BCA was stable in both water and PBS. The swelling ability of N-BCA in water was approximately 50 times its weight, which was about 6.5 times that of the freeze dried bacterial cellulose pellicles. N-BCA demonstrated no cytotoxicity against L929 mouse fibroblast cells. For long-term culture, N-BCA supported attachment, spreading, and proliferation of human gingival fibroblast (GF) on the surface. However, under static conditions, the cell migration and growth inside the scaffold were limited. Because of its biocompatibility and open macroporous structure, N-BCA could potentially be used as a scaffold for tissue engineering.