Bacterial Nanocellulose Films Research Articles

Modulating the Release Kinetics of Natural Product Actinomycin from Bacterial Nanocellulose Films and Their Antimicrobial Activity.

The present study aimed to create a more sustainable and controlled delivery system based on natural biopolymer bacterial nanocellulose (BNC) and bacterial natural product actinomycin (Act), with the applicative potential in the biomedical field. In order to provide improved interaction between BNC and the active compound, and thus to modulate the release kinetics, the TEMPO oxidation of BNC support was carried out. A mix of actinomycins from bacterial fermentation (ActX) were used as natural antimicrobial agents with an established bioactivity profile and clinical use. BNC and TEMPO-oxidized BNC films with incorporated active compounds were obtained and analyzed by FTIR, SEM, XPS, and XRD. The ActX release profiles were determined in phosphate-buffer solution, PBS, at 37 °C over time. FTIR analysis confirmed the improved incorporation and efficiency of ActX adsorption on oxidized BNC due to the availability of more active sites provided by oxidation. SEM analysis indicated the incorporation of ActX into the less-dense morphology of the TEMPO-oxidized BNC in comparison to pure BNC. The release kinetics of ActX were significantly affected by the BNC structure, and the activated BNC sample indicated the sustained release of active compounds over time, corresponding to the Fickian diffusion mechanism. Antimicrobial tests using Staphylococcus aureus NCTC 6571 confirmed the potency of this BNC-based system for biomedical applications, taking advantage of the capacity of modified BNC to control and modulate the release of bioactive compounds.

Bacterial valorization of agricultural-waste into a nano-sized cellulosic matrix for mitigating emerging pharmaceutical pollutants: An eco-benign approach

For Bacterial Nanocellulose (BNC) production, standard methods are well-established, but there is a pressing need to explore cost-effective alternatives for BNC commercialization. This study investigates the feasibility of using syrup prepared from maize stalk as a valuable nutrient and sustainable carbon source for BNC production. Our study achieved a remarkable BNC production yield of 19.457 g L−1 by utilizing Komagataeibacter saccharivorans NUWB1 in combination with components from the Hestrin-Schramm (HS) medium. Physicochemical properties revealed that the obtained BNC exhibited a crystallinity index of 60.5 %, tensile strength of 43.5 MPa along with enhanced thermostability reaching up to 360 °C. N2 adsorption-desorption isotherm of the BNC displayed characteristics of type IV, indicating the presence of a mesoporous structure. The produced BNC underwent thorough investigation, focusing on its efficacy in addressing environmental concerns, particularly in removing emerging pharmaceutical pollutants like Metformin and Paracetamol. Remarkably, the BNC exhibited strong adsorption capabilities, aligning with the Langmuir isotherm and pseudo-second-order model. Thermodynamic analysis confirmed a spontaneous and endothermic adsorption process. Furthermore, the BNC showed potential for regeneration, enabling up to five recycling cycles. Cytotoxicity and oxidative stress assays validated the biocompatibility of BNC. Lastly, the BNC films displayed an impressive 88.73 % biodegradation within 21 days.

Bacterial nanocellulose production using cost-effective, environmentally friendly, acid whey based approach

This study investigates the production of bacterial nanocellulose (BNC) film using a symbiotic culture of bacteria and yeasts (SCOBY) in acid whey medium. The yields were 59.58 g/L for wet and 2.75 g/L for freeze-dried BNC films in four days. The film contained cellulose nanofibrils with diameters ranging from 20 nm to 100 nm with a 34.3 % crystallinity index as confirmed by X-ray diffraction. Incorporating glycerol as a plasticizer modified the mechanical and thermal properties of the BNC film, reduced brittleness, and enhanced strain from 0.75 % to above 16 %. Fourier Transform Infrared Spectroscopy analysis identified intermolecular hydrogen bonding between the BNC film and glycerol. The glass transition temperature increased from roughly 158 °C to above 166 °C. The study validates the potential of acid whey as a viable alternative substrate for the production of BNC. The production method providing environmental benefits, cost-efficiency, and scalability, it also delivers an effective circular economy solution.

Green in situ immobilization of gold and silver nanoparticles on bacterial nanocellulose film using Punica granatum peels extract and their application as reusable catalysts.

In this study, Punica granatum peels extract induced in situ deposition was applied to prepare Au and Ag nanoparticles on bacterial nanocellulose film. Bacterial nanocellulose provided as an eco-friendly and excellent support for the interaction of P. granatum peel biomolecules and further reduction of Au and Ag ions. Meanwhile, a possible in situ growth mechanism of Au and Ag on bacterial cellulose by P. granatum peel extract biomolecules was presented. Further, the metal nanoparticles incorporated bacterial cellulose films were used to catalyze the reduction of 4-nitrophenol. The results of the present study indicated excellent catalytic reduction properties of Au and Ag nanocellulose films for 4 consecutive cycles. In addition, Au and Ag incorporated cellulose nanofiber films exhibited superior antioxidant activity and improved mechanical properties compared to pristine cellulose nanofiber film. The findings of this study may provide new insights and broad application of bacterial cellulose and green synthesis method for the development of various metal-cellulose composites.

Effect of addition polyethylene glycol on morphology and functional groups of composite films bacterial nanocellulose - graphite nanoplatelets

Polyethylene Glycol (PEG) existence on the composite film bacterial nanocellulose (BNC) reinforced with graphite nanoplatelets (GNP) has been analyzed in this research. Pineapple peel waste extract was used to synthesis the bacterial cellulose (BC) pellicle. A 1% NaOH solution was used to remove impurities from the BC pellicle. Mechanical disintegration and a high-pressure homogenization method were used to synthesize BNC. The high-pressure homogenizer (HPH) runs for five cycles at 150 bar before being filtered with a vacuum filter. The composite films are synthesized using a mixture of BNC, PEG 1%, and GNP 2.5%. Then the mixed slurry was dried using an oven for 14 hours at a temperature of 80 degrees Celsius. The morphology of composite BNC film was observed by using SEM. The addition of PEG causes the BC structure to become more porous. GNP is not well distributed in the BNC matrix but still acts as a dispersed filler. FTIR analysis is conducted to see its functional groups. The addition of GNP caused the hydroxyl group to be significantly reduced.

Fabrication of anti-Listeria film based on bacterial cellulose and Lactobacillus sakei-derived bioactive metabolites; application in meat packaging

More recently, probiotics-derived bioactive metabolites (so-called postbiotics; P) have gained more attention for antimicrobial food packaging. In this study, anti-Listeria active packaging films containing bacterial nanocellulose (BNC) and postbiotics of Lactobacillus sakei were fabricated, and their antibacterial performance was examined in in vitro condition and patty of buffalo meat. To facilitate postbiotics incorporation, ultrasound-assisted coating (UC, 40-kHz) and common coating (CC) were applied. The concentration of postbiotics and coating time were optimized by response surface methodology (RSM) and central composite design, and the antimicrobial activity of films was assessed by the disk diffusion method. The FTIR, mechanical, and surface morphologies of BNC-CC-P and BNC-UC-P films in optimized conditions (17 and 30% of postbiotics and 10 min coating time) were investigated. Based on the FTIR and SEM data, UC facilitated postbiotics incorporation into BNC, while tensile strength and elongation at break of BNC-CC-P and BNC-UC-P films were decreased and increased, respectively. Even though Listeria counts in patties with BNC film followed a similar trend with control samples without film and passed 107 CFU/g, samples wrapped with BNC-CC-P and BNC-UC-P films represented a 2.3 and 2.6 log CFU/g reduction in the bacterial count during storage (9 days at 8 °C), respectively. The findings of this work have provided worthwhile insights into the use of postbiotics in antimicrobial meat packaging for the control of foodborne pathogens. Ultrasound-assisted coating facilitated the rapid release of postbiotics from BNC into the meat matrix, signifying the importance of such a film for the packaging of foods having a short shelf life.

Optimizacija parametara sinteze nanokompozita na bazi bakterijske nanoceluloze/Fe3O4

Development in many areas of engineering and technology are closely linked to the development of new or improvement of existing materials. Having in mind wide use of bacterial nanocellulose (BNC) in various areas of everyday life, from biomedicine, ecology to electronics, BNC-based composites are becoming widely used and attracting the attention of the scientific community. It is especially important to examine in detail the synthesis parameters that affect the changes in the crystal structure and morphology of the obtained composites, having in mind that these changes have a crucial influence on their final functional properties. In this paper, a composite material based on bacterial nanocellulose BNC (as the matrix) and ferromagnetic Fe3O4 was studied. BNC was obtained by the activity of acetic fermentation bacteria after 7 days of growth in a suitable medium. The research is aimed to optimization of the Fe3O4 precipitation conditions. It's especially considering the time interval of BNC films spend in the iron salt solution. The influence of the performed synthesis conditions was considered by the SEMEDS, FTIR and XRD methods.

Development of Polyvinyl Alcohol/Chitosan/Modified Bacterial Nanocellulose Films Incorporated with 4-Hexylresorcinol for Food Packaging Applications

Development of Polyvinyl Alcohol/Chitosan/Modified Bacterial Nanocellulose Films Incorporated with 4-Hexylresorcinol for Food Packaging Applications

Surface Interactions between Bacterial Nanocellulose and B-Complex Vitamins.

The interactions between films of bacterial nanocellulose (BNC) and B complex vitamins were studied using a Quartz Crystal Microbalance with Dissipation monitoring (QCM-D). Thin films of BNC were generated in situ by QCM-D, followed by real-time measurements of the vitamin adsorption. The desorption of vitamins was induced by rinsing the system using phosphate buffers at a pH of 2 and 6.5, emulating gastric conditions. Changes in frequency (which are proportional to changes in adsorbed mass, ∆m) detected by QCM-D were used to determine the amounts of vitamin adsorbed and released from the BNC film. Additionally, changes in dissipation (∆D) were proven to be useful in identifying the effects of the pH in both pristine cellulose films and films with vitamin pre-adsorbed, following its changes during release. The effects of pH on the morphology of the vitamin-BNC surfaces were also monitored by changes in rugosity from images obtained by atomic force microscopy (AFM). Based on this data, we propose a model for the binding phenomena, with the contraction on the relaxation of the cellulose film depending on pH, resulting in an efficient vitamin delivery process.

Static intermittent fed-batch production of bacterial nanocellulose from black tea and its modification using chitosan to develop antibacterial green packaging material

Bio-based active packaging using biodegradable polymers is in great demand in the market due to its environment-friendly perspective but having the issues of high production cost, processing and performance. This study offers an industrially significant approach for the development of low-cost and eco-friendly bacterial nanocellulose (BNC) films using static intermittent fed-batch (SIFB) technology from low-cost medium i.e., fermented black tea. These BNC films were modified with a biopolymer–chitosan by simple immersion technique and analyzed for its usage as green and improved sustainable packaging material. After fermentation, the BNC was harvested, purified and oven-dried to obtain dry films. The results indicated a commendable BNC production of 29.2 gL-1 with the 63.2% substrate conversion to the BNC which was almost double than that obtained with a conventional static method (32%). The films were characterized using field emission scanning electron microscopy, attenuated total reflectance Fourier transform infrared spectroscopy, X-ray diffraction and thermogravimetric analysis. The antibiotic susceptibility test showed an inhibition zone of 40 ± 1 mm and 37 ± 3 mm for Escherichia coli and Aerococcus viridans, respectively for BNC-chitosan nano-biocomposite films showing their potential as an active packaging material. The presence of chitosan in the film is responsible for its antibacterial nature that might have caused cell wall lysis or inhibited protein synthesis in bacteria. Besides this, it’s good mechanical strength, crystalline nature, resistance to air and shelf life assessment of tomatoes showed the great potential of BNC-chitosan films to be used for low-cost active packaging, which is incalculably demanded by the packaging industry.

Bacterial nanocellulose from agro-industrial wastes: low-cost and enhanced production by Komagataeibacter saccharivorans MD1

Bacterial nanocellulose (BNC) has been drawing enormous attention because of its versatile properties. Herein, we shed light on the BNC production by a novel bacterial isolate (MD1) utilizing various agro-industrial wastes. Using 16S rRNA nucleotide sequences, the isolate was identified as Komagataeibacter saccharivorans MD1. For the first time, BNC synthesis by K. saccharivorans MD1 was investigated utilizing wastes of palm date, fig, and sugarcane molasses along with glucose on the Hestrin-Schramm (HS) medium as a control. After incubation for 168 h, the highest BNC yield was perceived on the molasses medium recording 3.9 g/L with an initial concentration of (v/v) 10%. The physicochemical characteristics of the BNC sheets were inspected adopting field-emission scanning electron microscope (FESEM), atomic force microscopy (AFM), X-ray diffraction (XRD), and Fourier transform infrared (FTIR) analysis. The FESEM characterization revealed no impact of the wastes on either fiber diameter or the branching scheme, whereas the AFM depicted a BNC film with minimal roughness was generated using date wastes. Furthermore, a high crystallinity index was estimated by XRD up to 94% for the date wastes-derived BNC, while the FTIR analyses exhibited very similar profiles for all BNC films. Additionally, mechanical characteristics and water holding capacity of the produced BNCs were studied. Our findings substantiated that expensive substrates could be exchanged by agro-industrial wastes for BNC production conserving its remarkable physical and microstructural properties.

Fabrication of natural-origin antibacterial nanocellulose films using bio-extracts for potential use in biomedical industry

This study explores the modification of bacterial nanocellulose (BNC), produced in fermented tea medium with bio-extracts from herbal plants, to produce entirely natural antibacterial nanocellulose films. The antibacterial property was imparted by impregnating the synthesized BNC into bio-extracts of Terminalia arjuna (arjuna), Azadirachta indica (neem), Withania somnifera (ashwagandha), Tinospora cordifolia (giloy), and Murraya koenigii (curry leaves). FE-SEM analysis of modified BNC films revealed the presence of cloudy layer of bio-extracts over the BNC nanofibrous network. The modified BNC production was confirmed by ATR-FTIR. The modified BNC showed tremendous antibacterial activity against Escherichia coli (E. coli) and Aerococcus viridians (A. viridans). T. arjuna modified BNC showed the highest antibacterial activity against E. coli and A. viridans with inhibition zone of 27.08 mm and 26.34 mm, respectively, while M. koeniggi modified BNC showed the lowest antibacterial activity for both E. coli and A. viridans with inhibition zone of 14 mm and 14.2 mm, respectively. The water retention, moisture content and porosity values reflect highly hydrophilic nature of BNC films and their well suitability for varied biomedical applications like antibacterial wound dressings, herbal biomasks, scaffoldings, etc. The modification of BNC films with the bio-extracts used in this study has not been reported previously.

Properties and antimicrobial activity of polyvinyl alcohol-modified bacterial nanocellulose packaging films incorporated with silver nanoparticles

An environmentally friendly antimicrobial film was developed by incorporating silver nanoparticles (AgNPs) into bacterial nanocellulose (BNC) via reduction (R) and UV-assisted (UV) methods. By mixing with 3 wt% polyvinyl alcohol (PVA) solution, the elongation at break of the films was improved 20 times that of pure BNC film. The films exhibited higher oxygen barrier capacity with slightly improved water vapor permeability. Antimicrobial activities against Escherichia coli O157:H7 were observed from both R and UV films with up to 7 and 3 log CFU/mL of reductions in liquid medium and on raw beef, respectively. A raw beef shelf-life study suggested that the films were able to inhibit the growth of naturally present bacteria for at least 10 days at 4 °C. The findings of this research indicate the potential of the AgNP/PVA/BNC films for applications in food packaging.

Biosynthesis of metallic nanoparticles using mulberry fruit (Morus alba L.) extract for the preparation of antimicrobial nanocellulose film

Aqueous extract of mulberry (Morus alba L.) fruit was used as a bio-functional reducing material for green synthesis of silver (Ag), copper (Cu) and palladium (Pd) metallic nanoparticles (NPs). The formation of NPs was monitored visually and characterized by UV–Vis spectroscopy and the morphology and size of the as-prepared NP were evaluated with TEM and dynamic light scattering, respectively. The synthesized Ag, Cu, and PdNPs were found to be spherical and non-regular in shape with average particle sizes ranging from 80 to150 nm (AgNPs), 50 to 200 nm (CuNPs) and 50 to 100 nm (PdNPs). The results represented that CuNP had a superior antibacterial activity against Escherichia coli O157:H7 and Listeria monocytogenes as compared to AgNPs and PdNPs. Furthermore, ex situ incorporation of NPs into bacterial nanocellulose (BNC) film made BNC with elevated antimicrobial capability on both tested microorganisms. NP–BNC films revealed different NP release pattern into food simulants depending on the type of NPs and simulants. The order of NP release rate from BNC in all food simulants (10, 50, and 95% ethanol) was as follows: CuNP > PdNP > AgNP. Accordingly, the fabricated BNC/NP nanocomposite film might be useful as a novel biomaterial to combat pathogens on food commodity.

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.

Evaluation of bacterial nanocellulose-based uniform wound dressing for large area skin transplantation

Bacterial nanocellulose (BNC) was biosynthesized by Gluconacetobacter xylinus. The surface area, physicochemical structure and morphology of the materials were characterized. Here provides a method for an efficient production of uniform BNC, which is beneficial for the fast characterization and evaluation of BNC. In vitro cytotoxicity of the materials was evaluated by the proliferation, the adhesion, the viability and the morphology of NIH/3T3 cells. Low cytotoxicity of the BNC was observed, and micrographs demonstrate a good proliferation and adhesion of NIH/3T3 cells on BNC. Large area full-thickness skin defects were made on the back of C57BL/6 mice in animal surgery. The wounds were transplanted with BNC films and the results compared to those in a control group. The rehabilitation of the wound surfaces and the pathological sections of mice were investigated and are discussed. Histological examinations demonstrated faster and better healing effect and lower inflammatory response in the BNC group than those in the control group. Preliminary results on wound dressings from BNC show a curative effect promoting the healing of epithelial tissue. BNC is a promising natural polymer with medical applications in wound dressings.