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BACKGROUND: Bacterial cellulose (BC) is a fiber substance produced by microbial fermentation. It is widely used in the food preservation industry because of its extremely pure texture, high crystallinity and high biocompatibility. In the present study, bacterial cellulose/thyme essential oil (BC/TEO‐E) with antibacterial and fresh‐keeping functions was prepared by ultrasonic treatment of modified bacterial cellulose for encapsulation of thyme essential oil, which effectively inhibited the spoilage of chilled chicken. RESULTS: The purified BC, produced by Acetobacter xylinum ATCC 53524, was ultrasonically treated wih different times (0, 30, 60 and 90 min). Transmission electron microscopy, scanning electron microscopy, Fourier transformed infrared spectroscopy, X‐ray diffraction, differential scanning calorimetry and zeta potential were used to characterize the structure of BC after ultrasound, showing that BC, treated for 30 min, had the optimal fiber structure, crystallinity (85.8%), thermal stability (347.77 °C) and solution stability (−26.63 ± 1.96 mV). BC/TEO‐E was prepared by a homogenizer for the preservation of chilled chicken. Optical microscopy indicated that the BC/TEO‐E prepared by 0.5% BC had optimal dispersion and stability, and even no delamination was observed in the emulsion. Compared with other groups (control, 0.5% BC and Tween‐E), the total number of colonies and coliforms in chilled chicken treated with 0.5% BC/TEO‐E was the lowest during the whole storage period (12 days), indicating that it can effectively inhibit bacterial growth. In addition, total volatile base nitrogen (TVB‐N), thiobarbituric acid reactive substances, pH and drip loss results showed that 0.5% BC/TEO‐E could effectively inhibit the spoilage of chilled chicken compared to the other treatment groups. CONCLUSION: All of the results acquired in the present study indicate that BC/TEO‐E has a potential application in chilled chicken preservation. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

In this study, a cost‐effective complex culture media containing molasses and corn steep liquor (CSL) was developed for the high production of bacterial cellulose (BC) by investigating the effect of four effective factors on BC production at three levels using Taguchi and combined methods. The predicted and actual values of BC production in optimal conditions by Taguchi and combined methods were 8.41 and 14.52 g/L, respectively. These results showed that the combined method was more suitable for predicting the optimal conditions in the optimization of BC production, the cost of developed culture medium was around 94% cost of HS medium preparation, molasses was the most effective factor in both experimental design methods, and initial pH adjustment had little impact on BC production. Then, the effect of inoculation conditions containing three factors of inoculation age, ethanol addition time, and agitation rate on the increase of BC production at three levels was investigated using the response surface methodology with the Box–Behnken design algorithm. Under the optimal conditions including inoculum age of 3 days, ethanol addition time of 10 days, and stirring speed of 100 rpm, the predicted and experimental results of BC production were 21.61 and 20.21 g/L, respectively. This is among the highest ever reported for BC production, which was achieved with a more cost‐effective culture medium containing molasses and CSL. [ABSTRACT FROM AUTHOR]

In the industrial application of bacterial cellulose (BC), the yield becomes a crucial factor because it drives the selling price of BC. A Box–Behnken experimental design with three components and three levels was employed to create seventeen samples. A response surface method was then used to optimize the BC yield from the most relevant parameters, including incubation temperature, medium shaking intensity, and nitrogen supply pH. Fourier transform infrared (FTIR) analysis proved that BC was pure. By analyzing BC morphology using scanning electron microscopy (SEM), rod-like microfibrils with an average diameter of 6.5 were revealed. X-ray diffraction (XRD) tested the crystalline size and crystallinity and found 4.7 nm and 69%, respectively. Thermal transition and stability were assessed using a differential scanning calorimeter (DSC) and a thermogravimetric analyzer (TGA). For the manufacture of BC composite hydrogel, a chemical test method was used to determine the solubility of BC. This study aimed to identify the ideal circumstances for using leftover sweet lime pulp for biomedical applications to produce reasonably priced and effective BC. At 28.87 °C, 125.91 rpm shaking frequency, and 5.65 pH, a sweet lime pulp waste medium produced the highest yield of BC, three times greater than the yield in a Hestrin–Schramm medium under static circumstances. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) stands out as a prominent biopolymer of global importance, distinguished by its unique advantages over plant-derived cellulose. Strains such as Acetobacter xylinum, renowned for their proficient BC production, draw considerable attention in both commercial and biomedical areas. This research aimed to selectively isolate cellulose-producing bacteria with enhanced efficiency from a variety of fruit samples utilizing a cost-effective methodology. A total of 60 fruit samples were selected, and the assessment focused on 17 strains derived from rotten banana, red apple, green apple, and pineapple samples. The evaluation encompassed an examination of bacteriological traits and cellulose synthesis, with subsequent identification of strains achieved through DNA extraction and 16S rRNA PCR analysis. The experimental findings reveal cellulose-producing strains, including model A. xylinum (KCCM 40407) obtained from the Pharmacy lab of COMSATS University Islamabad Abbottabad Campus, Pakistan, designated as number 2, serving as a control. Notably, strains isolated from deteriorated fruits (samples 1, 4, 8, 11, 12, and 15) demonstrated the capacity to produce soluble cellulose. A. xylinum (model strain 2) was cultured under static conditions in HS media, demonstrating remarkable efficacy for cellulose sheet production. Subsequent characterization employing scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) unveiled a nano-fiber mat featuring multi-layered fibers. This eco-friendly approach has the potential for large-scale, high-quality cellulose production, applicable in biomedical and industrial fields. The research highlights an environmentally sustainable and economically viable method for cellulose production, presenting potential applicability across biomedical and industrial arenas on a significant scale.

ABSTRACTBacterial cellulose is a natural polymer, usually produced through synthetic (chemically defined) or natural media. However, the current methods of bacterial cellulose production are not ideal because of their low productivity and large number of byproducts. In order to improve the yield of bacterial cellulose, the influence of medium composition, culture time, culture temperature and culture pH on the production of bacterial cellulose by Acetobacter xylinum ATCC 23,767 was studied by single factor method. The optimal medium composition for Acetobacter xylinum can be analyzed by Thermal field emission scanning electron microscopy (TF-SEM) as glucose (20 g/L), yeast extract (5 g/L), peptone (5 g/L), citric acid (2 g/L). Using the logarithmic calculation method, we can determine that the optimal culture conditions are controlled by initial pH of the culture medium of 6 and constant static culture at 28°C for 9 days. Using TF-SEM, Fourier transform infrared (FT-IR) spectroscopy and water contact angle test, the best post-treatment solution can be selected as sodium hydroxide (1%). The results showed that the yield of bacterial cellulose could reach up to 8.5 g/L under the above conditions, and the obtained product exhibited a dense three-dimensional network structure.

Bacterial cellulose (BC) stands out as a prominent biopolymer of global importance, distinguished by its unique advantages over plant-derived cellulose. Strains such as Acetobacter xylinum, renowned for their proficient BC production, draw considerable attention in both commercial and biomedical areas. This research aimed to selectively isolate cellulose-producing bacteria with enhanced efficiency from a variety of fruit samples utilizing a cost-effective methodology. A total of 60 fruit samples were selected, and the assessment focused on 17 strains derived from rotten banana, red apple, green apple, and pineapple samples. The evaluation encompassed an examination of bacteriological traits and cellulose synthesis, with subsequent identification of strains achieved through DNA extraction and 16S rRNA PCR analysis. The experimental findings reveal cellulose-producing strains, including model A. xylinum (KCCM 40407) obtained from the Pharmacy lab of COMSATS University Islamabad Abbottabad Campus, Pakistan, designated as number 2, serving as a control. Notably, strains isolated from deteriorated fruits (samples 1, 4, 8, 11, 12, and 15) demonstrated the capacity to produce soluble cellulose. A. xylinum (model strain 2) was cultured under static conditions in HS media, demonstrating remarkable efficacy for cellulose sheet production. Subsequent characterization employing scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) unveiled a nano-fiber mat featuring -layered fibers. This eco-friendly approach has the potential for large-scale, high-quality cellulose production, applicable in biomedical and industrial fields. The research highlights an environmentally sustainable and economically viable method for cellulose production, presenting potential applicability across biomedical and industrial arenas on a significant scale. [ABSTRACT FROM AUTHOR]

This study investigates the synthesis and the antibacterial properties of bacterial cellulose (BC) incorporated zinc phosphate nanocomposite-mediated dragon fruit extract (BC-ZP-DF). The composite was prepared by a three-step process that involved bacterial cellulose (BC), zinc phosphate (ZP), and nanocomposite BC-ZP synthesis. BC was prepared by fermenting coconut water with the components of ammonium sulfate, acetic acid, and Acetobacter xylinum culture. Zinc phosphate was made through the green synthesis method by reacting zinc nitrate and diammonium hydrogen phosphate using a sensitizer agent from red dragon fruit peel extract (DF) with volume variations of 5, 10, 20, 30, 40, and 50 mL. The composite was prepared by immersing BC with zinc phosphate. Phase crystallinity, functional group, and morphology of the samples were characterized using XRD, FTIR, and SEM. It was found that the nanocomposite was constructed by the nano green of zinc phosphate in the form of a hopeite structure with antibacterial PO43- and OH functional groups. Morphological analysis using SEM revealed that the nanocomposites contained various small powder grains. Based on the FTIR spectrum, XRD pattern, and surface morphology of composite film, the incorporation of zinc phosphate in the BC framework was confirmed. The antibacterial activity tests of nanocomposite films using Staphylococcus aureus and Pseudomonas aeruginosa bacteria revealed that the nanocomposite was highly effective in inhibiting both bacteria, and the nanocomposite BC-ZP-DF10 film had the strongest inhibition. The results of the air filter test exhibited that the composition was efficient on all films with the highest percent of efficiency (%E) of 90.10%. [ABSTRACT FROM AUTHOR]

Extensive work on bacterial cellulose (BC) cultivation is crucial in optimizing BC performance and versatility in application. Herein, this study aims to investigate the lignin content in oil palm frond (OPF) juice medium that could affect the BC production by Acetobacter xylinum 0416 in static culture. The effects of lignin content were observed by the performances of BC production from the raw and pre-treated OPF juice medium fermentation with Hestrin-Schramm (HS) medium as a point of comparison. The TAPPI methods analysis outlined up to 3.719 g/L of total lignin content in raw OPF juice and FTIR analysis depicted the functional group of a typical lignin compound, thus confirming its presence as a component inhibitor. The raw OPF juice was further pre-treated using an alkaline precipitation method resulting in acid-insoluble lignin removal up to 75.47% of the total lignin content. The results revealed that the BC yield from the raw OPF juice fermentation was lower compared to the HS medium with dried BC content of 0.152 g/L and 2.52 g/L, respectively. The BC cultivation using the pre-treated OPF juice medium was improved as the BC yield significantly increased to 1.91 g/L. Therefore, a proper pre-treatment strategy on OPF juice medium for lignin content removal could improve the medium capability in BC cultivation for higher-scale production. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) microstructured biomaterials are favorable in tissue engineering due to their superior guidance to cellular activities. Herein, we developed a 3D microstructured bacterial cellulose (BC) with arranged fibers by controlling Acetobacter xylinum through an electric field (EF) application. The real-time video analysis showed that EF directed the migration of A. xylinum and increased its migration speed with the increased EF. The bacteria quickly changed direction with high motility in response to the switch on/off of the EF. In the long-term electrical stimulation (ES), the growth of A. xylinum was influenced. Likewise, bacterial cells were oriented along the direction of EF while bacteria simultaneously produced nanocellulose, resulting in 3D networks with aligned fibers. The prepared 5 mA-BC hydrogels presented the ordered 3D microstructure with higher fiber alignment, diameter and flexibility than that of NO EF-BC hydrogels. The in vitro biological evaluation demonstrated that the 5 mA-BC hydrogels were biocompatible whereon NIH3T3 cells proliferated along the direction of fiber alignment. These findings demonstrate that ES provides a promising strategy for the natural fabrication of aligned 3D microstructured BC to guide cellular activities for tissue regeneration. [ABSTRACT FROM AUTHOR]

Acetobacter spp. that are commonly found on fruits, can perform oxidation processes, resulting in acetic acid production in vinegar. Besides that, Acetobacter spp. able to produce bacterial cellulose (BC), which is an essential by-product. This present study was carried out to isolate Acetobacter spp. from selected local fruits. Species verification of the bacterial isolates was performed using molecular and bioinformatic approaches. A total of six local fruits (starfruit, jackfruit, watermelon, pineapple, honeydew & banana) were subjected to seven days of fermentation in a brown sugar solution. Acetobacter spp. were isolated from the fermented medium using bromocresol green ethanol agar as the selective medium. Thirteen bacterial isolates were obtained and subjected to molecular works, including DNA extraction and PCR amplification using universal primers, targeting the 16S rRNA genes. PCRamplified products were selected for single-pass sequencing. BLASTn analysis of the sequencing results showed three isolates (23.1%) belonging to Acetobacter tropicalis and one isolate (7.7%) representing Gluconobacter oxydans might have potential in BC production. However, the remaining nine isolates (69.2%) hit the Lactobacillus genus. Morphological observation using FESEM showed that the BC produced by all the positive bacterial isolates is similar to dried nata de coco and BC produced by Acetobacter xylinum. In addition, four similar regions of -OH stretch (3400 - 3300 cm-1), -CH stretch (2970 to 2800 cm-1), -OH bending (1620 cm-1), and -COC stretch (1100 to 1073 cm-1) are identified in the BC samples. In the future, the isolated Acetobacter and Gluconobacter strains could be further utilized for large-scale BC production in a suitable fermentation medium. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a potential eco-friendly biopolymer. BC has higher crystallinity and purity compared to plant cellulose. Scientific studies on the production of BC from lactic acid bacteria (LAB) are minimal compared to other common bacteria such as Acetobacter xylinum. LAB was screened and isolated from different tissues of Mimosa pudica (medicinal plant) using MRS broth and agar as the selective medium. LAB isolates were subjected to 16S rRNA gene sequencing of all the bacterial isolates. BC was produced from all LAB isolates by incubating at 30 °C for 14 days in herbal tea medium (Strobilanthes crispus) and HS medium (control) with 130 rpm agitation. BC produced by two selected bacterial isolates was characterized using FESEM, FTIR, XRD, and TGA. Molecular analysis of the 16S rRNA gene of all the potential LAB isolates shows 99.86 - 100% identity to 16S rRNA sequences of other Lactobacillus plantarum strains. Two selected L. plantarum strains (LBM001 & LBM004) produce BC in sphere-like particles with a 1.4 to 2.2 µm diameter range of microfiber. FTIR analysis shows that BC produced by LBM001 and LBM004 have four similar cellulose regions identified in cellulose from other sources, which are O-H stretch (3400-330 cm-1), C-H stretch (2970-2800 cm-1), O-H bending (1620cm-1) and C-O-C stretch (1100-1073 cm-1). XRD analysis shows BC produced by the L. plantarum strains consists of two different XRD peaks at the 2? angle of 21.53° and 21.85° instead of a single peak (22.76°) identified in the BC produced by A. xylinum and plant cellulose. A similar TG and DTG curved pattern was detected in the BC produced by the L. plantarum strains with the BC produced by A. xylinum and plant cellulose. The LAB isolates from M. pudica have potential in BC production based on the multiple characterization studies. [ABSTRACT FROM AUTHOR]

Nata adalah selulosa dari bakteri yang diperoleh dari fermentasi Acetobacter xylinum. Nata sering ditemukan dalam makanan penutup sebagai suplemen kesehatan karena kandungan seratnya yang tinggi. Nata tidak hanya dihasilkan dari air kelapa yang dikenal dengan nata-de-coco, tetapi juga dapat dihasilkan dari sumber lain seperti air limbah cucian beras yang disebut dengan nata-de-leri. Penelitian ini bertujuan untuk mengoptimalkan parameter dalam fermentasi nata-de-leri dengan metode statistik dalam rangka meningkatkan produksi nata. Hal yang dilakukan yaitu, pertama melakukan desain untuk menyeleksi parameter yang berpegaruh menggunakan respon yield menggunakan Design Placket-Burman. Ada delapan factor yang kaji untuk kemudian didapatkan faktor yang paling berpengaduh agar mudah dalam optimasi nantinya. Hal kedua yang dilakukan adalah optimasi empat parameter yang paling berpengaruh menggunakan Central Composite Design (CCD) dengan respon hasil yield. Hasil dari penelitian menunjukkan bahwa konsentrasi gula, konsentrasi CO(NH2)2, konsentrasi starter inokulum dan waktu fermentasi merupakan faktor yang penting dalam produksi nata de leri. Hasil parameter untuk menghasilkan yield optimal dalam produksi nata de leri ketika menggunakan 500 ml substrat limbah cucian beras adalah menggunakan gula sebanyak 17,5 g; CO(NH2)2 sebanyak 12 g; volume starter sebanyak 60 mL dan waktu fermentasi selama 12 hari. Dari parameter tersebut menghasilkan rendemen sebesar 97,20%. Dari optimasi dalam penelitian ini menghasilkan peningkatan produksi nata de leri sebesar 20% dari kondisi awal sebelum dioptimasi.

The fashion industry is well known for its highly polluting production processes. Researchers around the world still are looking for alternative sustainable raw materials. Bacterial cellulose is one such biomaterial, sustainable, and environmental friendly and has a lot of potential in the fashion industry. In this review, the application possibility of bacterial cellulose in the fashion industry is taken as a major concern. The review mainly focuses on the previous researches in the area to evaluate the various production methods and raw materials used in bacterial cellulose manufacturing using Acetobacter xylinum. In addition to that, the review also consolidates the carbon source materials utilized for the bacterial cellulose production by various researchers. In specific, the fashion application-related research works were analyzed. It was found that production cost and lower yield are the major issues in the bulk production of bacterial cellulose and hence, the search continues for cost-effective raw materials with better cellulose yield. The tea medium is so far successfully used for bacterial cellulose fabric production. However, the inherent properties like higher water-holding capacity, loss of flexibility, and structural disorientation on drying are addressed as major issues concerning the fashion industry.

The competitiveness of bacterial cellulose (BC) production with plant cellulose can be achieved by production on cost-effective media. It was found that the bacterial cell number ratio of BC to culture medium increases over time so that from the fourth day, the entrapped cell number in the cellulose network exceeds the suspended cells. Optimization based on 23-full factorial showed that inoculum development at 50 rpm and the main culture process under static conditions significantly increases BC production. A cost-effective culture medium containing molasses (ML) and corn steep liquor (CSL) was developed based on the same C/N ratio to HS medium, with 7.24 g/l cellulose at C/N ratio 12.6 is competitive with maximum production 8.7 g/L in HS medium. The BC production cost was reduced about 94% using the proposed cheap and locally available medium containing ML and CSL, while BC mechanical properties increased by about 50%. [ABSTRACT FROM AUTHOR]

The development of alternative food packaging films using bio-based residues is in great demand for replacing petroleum-based packaging materials. However, large-scale application is severely limited by costly production and poor performance. This study investigates the ex-situ modification of bacterial cellulose (BC) produced by Acetobacter xylinum in oil palm fronds juice to obtain BC-Chitosan (BCC) films. FTIR revealed the structure of amide I and II bands, confirming the presence of chitosan in BCC films. The FE-SEM images of BCC films showed the formation of a thick chitosan layer with increasing chitosan incorporated into the BC surface structure. The coated chitosan layer observed improved mechanical properties in BCC films due to the disappearance of empty pores between BC fibers. Increments in chitosan concentration slightly decreased the thermal behavior of BCC. The antimicrobial effects of BCC films were effective against Gram-positive bacteria (Staphylococcus aureus) when the concentration of chitosan incorporated was above 0.6 %w/v. This study reveals the potential of extending the application of BC derived from oil palm frond juice (OPFJ) for developing food packaging materials. [ABSTRACT FROM AUTHOR]

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Renewable fermentation feedstock from a freshly cut oil palm frond (OPF) is a promising medium for bacterial cellulose (BC) production. Herein, this study assessed its suitability as a solitary medium for the production of BC using Acetobacter xylinum 0416 in a static culture. The proximate composition and components analysis revealed up to 36.2 g/L of fermentable sugars and vital nutrients were available in OPF juice. Meanwhile, the effect of OPF juice concentration and initial pH arrangement shows that the maximum yield of BC (2.33 g/L) was obtained using 60% v/v of OPF juice concentration at initial pH 3.5 and incubated at 30℃ for 14 days. Besides, pure OPF juice showed a minimum in BC production due to the presence of inhibitory component suspected to be the lignin content. The kinetic study was elucidated for BC produced from OPF juice and compared with coconut water medium. The FT-IR and XRD spectra, and FE-SEM micrograph analysis for the BC showed the typical peaks represent in cellulose with a crystallinity index of 82.4% and threadlike microfibrils structure ranging from 35.6.5 nm to 77.5 nm. Thus, OPF juice is a solely sufficient medium that offers a positive alternative to BC production. [ABSTRACT FROM AUTHOR]

This work aimed at conversion of worthless indurtial wastes to valuable product. Herein, bioactive composites based on bacterial cellulose (BC) and eggshell or eggshell-derived hydroxyapatite (HAp) were prepared by a green method using Gluconacetobacter xylinum bacteria. The effect of addition of eggshell (BC/Eg) and eggshell-derived HAp (BC/HAp-Eg) on the bacterial cellulose yield, biodegradation and biocompatibility was studied. For comparison, HAp derived from chemical precursors was synthesized (BC/HAp-ch). The resultant composites were characterized by XRD, FTIR, and SEM/EDX. Furthermore, the biodegradation and bioactivity were assessed in SBF, and the cell viability was studied against oral normal cells. The results showed that the productivity of BC applied HAp-derived eggshell (1.83 g/L) was higher than that of using (1.37 g/L). Interestingly, the eggshell was converted to Ca3(PO4)2 during incubation in the bacterial culture medium, while Ca3(PO4)2 was formed as a secondary phase when using either eggshell-derived HAp or chemically-derived. The in vitro bioactivity test in SBF showed that all composites were induced the formation of a bone-like apatite layer on their surface with Ca/P ratio, 1.49, 1.35, and 1.41 for BC/Eg, BC/HAp-ch, and BC/HAp-Eg, respectively, near to the ratio in the natural HAp. Finally, the in vitro cell viability test was confirmed good biocompatibility against the composites. However, at high sample concentration (250 µg/mL), BC/HA-Eg showed the higher cell viability (95.2%) than that of BC/Eg (80.5%) and BC/HA-ch (86.2%). In conclusion, eggshell waste could be used directly with bacterial cellulose to produce bioactive composites without the need to convert it to HAp which reduced the cost of production and thus has a higher economic return. Obiviously, eggshell waste can act as calcium, organic matter source, pH preservation, nuterilizing agent along with potential instead of costly buffering agent in the BC culture medium and further for increased the BC production. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) producing bacterial strains were isolated from bio-extract (BE). Nine isolates that can produce BC in Hestrin–Schramm medium (HS medium) were identified. The BC production of these isolates was then investigated using agricultural waste as a raw material. The agricultural waste (banana, papaya, dragon fruit, and mango peels) was used as a carbon source for BC production. After incubation, the highest dry weight of BC reached 0.93±0.27 g/L, and 4.07±0.27 g/L was obtained from isolate BE073 in a medium containing mango and dragon fruit peels because the raw materials state is appropriate for bacterial growth. In a medium with papaya peel, the highest dry weight of BC was obtained from isolate BE052 at about 1.08±0.05 g/L. None of the strains was able to grow with the banana medium. However, all the isolate strains could grow and produce BC in the HS medium. The maximum dry weights of BC of 4.31±0.45 g/L, 4.23±0.13 g/L, and 4.21±0.25 g/L were obtained from isolates BE123, BE052, and BE073, respectively, and Acetobacter xylinum produced BC at 2.39±0.11 g/L. The structure and physical properties of BC produced from bacterial isolates using agricultural waste were characterized. It was similar to BC produced from HS medium and production from the reference strain A. xylinum. This study demonstrates the ability for BC production of bacterial strains isolated from bio-extract. It is also demonstrated that agricultural waste is a suitable and alternative carbon source for raw material in BC production. [ABSTRACT FROM AUTHOR]

The liquid waste from the production of fruit preserves was used as an alternative carbon source to replace sugar in the traditional Hestrin-Schramm (HS) and coconut water media (CM) and reduce the cost of bacterial cellulose (BC) production. The sugar components of liquid wastes from preserved tamarind (LWT) and preserved mango (LWM) were characterized, and the total sugars were between 237.50 g/L and 231.90 g/L. The effects of the nutrients in the media with LWT and LWM on the production of BC by Acetobacter xylinum were determined. The result showed that A. xylinum could grow and produce BC in the media with liquid waste. The highest concentration of BC, 6.60±0.04 g/L, was obtained from the medium containing 25% (v/v) LWM. In a medium containing LWT, A. xylinum produced a maximum BC of 5.50±0.30 g/L when 12.5% (v/v) LWM was added. However, when the structure and physical properties of the BC from the liquid waste were characterized, it was similar to BC from the HS medium and CM medium without liquid waste. [ABSTRACT FROM AUTHOR]

The fashion industry is well known for its highly polluting production processes. Researchers around the world still are looking for alternative sustainable raw materials. Bacterial cellulose is one such biomaterial, sustainable, and environmental friendly and has a lot of potential in the fashion industry. In this review, the application possibility of bacterial cellulose in the fashion industry is taken as a major concern. The review mainly focuses on the previous researches in the area to evaluate the various production methods and raw materials used in bacterial cellulose manufacturing using Acetobacter xylinum. In addition to that, the review also consolidates the carbon source materials utilized for the bacterial cellulose production by various researchers. In specific, the fashion application-related research works were analyzed. It was found that production cost and lower yield are the major issues in the bulk production of bacterial cellulose and hence, the search continues for cost-effective raw materials with better cellulose yield. The tea medium is so far successfully used for bacterial cellulose fabric production. However, the inherent properties like higher water-holding capacity, loss of flexibility, and structural disorientation on drying are addressed as major issues concerning the fashion industry. [ABSTRACT FROM AUTHOR]

This paper describes the interaction and properties of bacterial cellulose (BC)–ciprofloxacin composites synthesized by in situ incorporation method. Ciprofloxacin's susceptibility to BC's producer, Acetobacter xylinum 0416, was first tested to determine its inhibitory activity against the bacteria. In situ incorporation method was performed by introducing 0.2% (w/v) ciprofloxacin into Hestrin–Schramm medium at the onset of exponential phase of A. xylinum 0416 growth. Following a 10-day incubation at 28 °C, BC–ciprofloxacin composites were harvested and further characterised, while another BC–ciprofloxacin composite was harvested and purified prior to characterisation. The interaction between ciprofloxacin and BC was proven by the presence of quinolines and fluorine groups of ciprofloxacin on unpurified BC–ciprofloxacin composite and the reduction of crystallinity index as compared to the native BC. Moreover, deposited ciprofloxacin crystals on BC film and its composition were exhibited via SEM-Energy-dispersive X-ray analysis. Unpurified BC–ciprofloxacin film was determined to have strongly inhibited the following selected diabetic foot ulcer bacteria: E. coli, K. pneumoniae and P. aeruginosa. BC has the potential to be used as a wound dressing and a carrier for ciprofloxacin.

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Cheese whey (CW) constitutes a dairy industry by-product, with considerable polluting impact, related mostly with lactose. Numerous bioprocessing approaches have been suggested for lactose utilization, however, full exploitation is hindered by strain specificity for lactose consumption, entailing a confined range of end-products. Thus, we developed a CW valorization process generating high added-value products (crude enzymes, nutrient supplements, biopolymers). First, the ability of Aspergillus awamori to secrete β-galactosidase was studied under several conditions during solid-state fermentation (SSF). Maximum enzyme activity (148 U/g) was obtained at 70% initial moisture content after three days. Crude enzymatic extracts were further implemented to hydrolyze CW lactose, assessing the effect of hydrolysis time, temperature and initial enzymatic activity. Complete lactose hydrolysis was obtained after 36 h, using 15 U/mL initial enzymatic activity. Subsequently, submerged fermentations were performed with the produced hydrolysates as onset feedstocks to produce bacterial cellulose (5.6–7 g/L). Our findings indicate a novel approach to valorize CW via the production of crude enzymes and lactose hydrolysis, aiming to unfold the output potential of intermediate product formation and end-product applications. Likewise, this study generated a bio-based material to be further introduced in novel food formulations, elaborating and conforming with the basic pillars of circular economy. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) produced by Acetobacter xylinum has great advantages in wound dressing. However, the structural limitation under static culture, and lack of antibacterial properties restrict its application, especially for infectious wound healing. The present study reported an original wound dressing, which was composed of a Janus BC membrane with antibacterial nano-sized copper oxide (CuO) through polydopamine (PDA) conjugation to promote wound healing under infectious condition. The finished product (CuO/PDA/BC membrane) exhibited favorable air permeability, high hydrophilicity and good mechanical properties, as well as strong antibacterial effects by the sustained release of CuO and photothermal effect of CuO/PDA. Furthermore, CuO/PDA/BC membrane inhibited inflammatory response and promoted wound healing in an infectious wound model in vivo. These results suggested that our CuO/PDA/BC membrane had great potential as wound dressing for infectious wound healing. [Display omitted] [ABSTRACT FROM AUTHOR]

The study presents the preparation and characterization of new scaffolds based on bacterial cellulose and keratin hydrogel which were seeded with adipose stem cells. The bacterial cellulose was obtained by developing an Acetobacter xylinum culture and was visualized using SEM (scanning electron microscopy) and elementally determined through EDAX (dispersive X-ray analysis) tests. Keratin species (β–keratose and γ-keratose) was extracted by hydrolytic degradation from non-dyed human hair. SEM, EDAX and conductometric titration tests were performed for physical–chemical and morphological evaluation. Cytocompatibility tests performed in vitro confirmed the material non-toxic effect on cells. The scaffolds, with and without stem cells, were grafted on the burned wounds on the rabbit's dorsal region and the grafts were monitored for 21 days after the application on the wounds. The clinical monitoring of the grafts and the histopathological examination demonstrated the regenerative potential of the bacterial cellulose–keratin scaffolds, under the test conditions. [ABSTRACT FROM AUTHOR]

Bacterial Cellulose is relatively pure, hydrophilic, has crystallinity index and tensile strength higher. Therefore Bacterial Cellulose has been widely used for biomaterial as woun healing, artificial blood vessel, drug delivery etc. Bacterial cellulose supplemented Centella Asiatica L. Urban had been produced from acetobacter xylinum using the saturating method. The aim is to enhance the characterization of Bacterial Cellulose by adding Centella Asiatica L. Urban extract. Bacterial cellulose (BC) and Bacterial cellulose supplemented Centella Asiatica L. Urban (BCCA) were characterized by FTIR test, SEM test, Mechanical Test, and XRD test. The result showed that adding Centella Asiatica L. Urban extract enhances the characterization of Bacterial Cellulose. Mechanical Test showed decrease mechanical properties of BC, and XRD showed Supplemented Centella Asiatic L. Urban extract did not disturb the regularity of BC chains and increased the crystallinity index. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) was synthesized by Acetobacter xylinum using a carbon source of coconut shell hydrolysate, which was treated with an ultra-low concentration of sulfuric acid. The coconut shell was found to contain 57.13% holocellulose and 27.42% lignin. The effect of sulfuric acid concentration, reaction temperature, and reaction time on hydrolysis of coconut shell were evaluated by response surface methodology. The reducing sugar concentration was 8.39 g/L under the predicted optimum treatment at 200 °C for 32 min with a solution of 0.07% sulfuric acid. The holocellulose conversion rate was 56.1% at this condition. In a detoxification process using calcium hydroxide and activated carbon, furfural and hydroxymethylfurfural in the hydrolysate were almost completely removed, whereas formic acid and acetic acid levels decreased by 30%. After cultivation for 7 days at the reducing sugar status of 5 g/L, the BC production in medium with the detoxified hydrolysate could reach 1.66 g/L. After fermentation for 21 days, BC yield in medium using composited carbon source (20 g/L) of glucose and hydrolysate was 5.30 g/L. Structural analysis showed that BC obtained from medium of control and detoxified hydrolysate exhibited similar properties. This work provided a potential method for BC production. [ABSTRACT FROM AUTHOR]

The bacterial cellulose production (BCP) process, using cellulose microfibrils (CM) of Acetobacter xylinum enmeshed on luffa sponge matrices (LSM) as LSM-CM starter, has been successfully developed where the LSM-CM production process can be recycled through consecutive cycles in limited dissolved oxygen (DO) under continuous aeration. In this study, incremental aeration rates impacted the consecutive cycles. Gluconic acid production, during the process, resulting in the reduction of BCP, was increasingly generated at high aeration from 0.28 to 0.34% at 3 L/min to 0.83–0.97% and 1.52–1.99% at 6 and 9 L/min after 7 d culture at 30 ± 2 °C. To compensate for the negative impact of aeration, 0.10 and 0.15% (w/v) carboxymethyl cellulose (CMC) was found to create a microenvironment for recycled LSM-CM at both high aeration (6 and 9 L/min, respectively). Under nine consecutive BCP cycles, acceptable BC yields (from 5.54 ± 0.5 to 5.89 ± 0.5 g/L) were associated with high biomass at 6 L/min aeration. These results confirm that LSM-CM, combined with CMC called as LSM-CM-CMC, created microenvironments low in DO under high aeration rates and that the recycled LSM-CM-CMC with aeration is an alternative, sustainable, economic process that could be applied for mass BCP. [ABSTRACT FROM AUTHOR]

Cheese whey (CW) constitutes a dairy industry by-product, with considerable polluting impact, related mostly with lactose. Numerous bioprocessing approaches have been suggested for lactose utilization, however, full exploitation is hindered by strain specificity for lactose consumption, entailing a confined range of end-products. Thus, we developed a CW valorization process generating high added-value products (crude enzymes, nutrient supplements, biopolymers). First, the ability of Aspergillus awamori to secrete β-galactosidase was studied under several conditions during solid-state fermentation (SSF). Maximum enzyme activity (148 U/g) was obtained at 70% initial moisture content after three days. Crude enzymatic extracts were further implemented to hydrolyze CW lactose, assessing the effect of hydrolysis time, temperature and initial enzymatic activity. Complete lactose hydrolysis was obtained after 36 h, using 15 U/mL initial enzymatic activity. Subsequently, submerged fermentations were performed with the produced hydrolysates as onset feedstocks to produce bacterial cellulose (5.6–7 g/L). Our findings indicate a novel approach to valorize CW via the production of crude enzymes and lactose hydrolysis, aiming to unfold the output potential of intermediate product formation and end-product applications. Likewise, this study generated a bio-based material to be further introduced in novel food formulations, elaborating and conforming with the basic pillars of circular economy.

Bacterial cellulose (BC) is a promising and renewable nanomaterial due to its unique structural features and appealing properties. Intensive study on BC preparation has been mainly focused on biosynthesis by certain bacteria, while the high economic costs of fermentation, especially the carbon sources, remain challenges to its application. In this study, bacterial cellulose was synthesized by Acetobacter xylinum with the acetic acid hydrolysate of bagasse used as carbon source. After the bagasse was pretreated by acetic acid, the components in hydrolysate and the removal rate was investigated, and the pretreatment conditions were optimized as follows: temperature of 160 °C, heating time of 60 min, addition of acetic acid of 2.0% (m/m), and solid-to-liquid ratio of 1/5. Prior to Acetobacter xylinum cultivation, the hydrolysate was detoxified by activated carbon. The detoxification process was very efficient for BC production, with a yield up to 2.13 g/L when the dosage of activated carbon was 5% (m/V). Furthermore, the obtained BC was characterized by scanning electron microscopy (SEM), which showed that the ribbons width of BC was between 30 and 80 nm. X-ray patterns showed the crystallinity value was 74.6 % and the crystallinity index (CI%) was 66.5 %, which also evidenced the presence of peaks characteristic of Cellulose I polymorph. In conclusion, it is feasible to produce BC from bagasse hydrolysate. This model of waste recycling could aid in the development of sustainable strategies.

Summary: This paper reports on the treatment of Acetobacter xylinum (CGMCC No. 7431) by ultraviolet (UV) to investigate the role of mutagenesis on the production of cellulose. When Acetobacter xylinum was treated at intervals of UV mutagenesis, the treatment times of 3 and 4 min formed more compact bacterial cellulose. The activation conditions, including the medium nutrients that affected the yield of bacterial cellulose, were investigated including the use of coconut milk. The optimal yield of bacterial cellulose was 43.91 ± 3.89 g L−1, which was 1.22 times higher than that obtained from the wild type without any treatment. The experimental results suggested that different UV factors could significantly affect the yield of bacterial cellulose. The resulting bacterial cellulose has a potential as a novel functional food material. [ABSTRACT FROM AUTHOR]

The recent study aimed to isolates Acetobacter xylinum from local home vinegar samples processed of apple, dates and grape. From the total fifty; Twenty-one isolates observed on the surface of HS-agar medium, only four isolates showed transparent zone around the colony on GYC agar plates. The isolates (B1, B2, B3 and B4) were examined for bacterial cellulose production in HS broth medium. The dry weight of crude cellulose produced by each isolates was measured and ranged from 0.36 - 0.42 gm. The pH value of bacterial cellulose were (6.2 - 6.9), approximately equal and nearly to the neutral values with comparison with plant cellulose. The thickness of bacterial cellulose membrane is a key parameter in preparing film, the initial thickness of the wet BC membrane was measured as 32 micrometers and after drying the computed thickness of BC membrane decreased to 0.4 micrometers. The average tensile strength value and the average elongation at break value of the dried BC films were 34.5 MPa and 5.2% respectively. The micrograph of BC shows three dimensional porous network structure formed by ribbon fibrils, randomness of fiber distribution without any specific orientation. The SEM micrograph obtained for the purified Bacterial Cellulose (BC) shown a very similar structure with the commercial Plant Cellulose (PC). Furthermore, the fibrils were densely packed ; the aggregated BC showed flat and were smoother surface compared to the PC. X-ray diffraction analysis is used to study the physical properties of both BC and PC samples such as morphology, the degree of crystallinity, crystal size and to categorize cellulose as type Ior I. 2 range 5o to 40o is usually adequate to cover the most important area of the XRD pattern. The pattern for BC revealed four main peaks were at 2 = 14.53, 16.78, 22.79 and 34.67, corresponding to the crystallographic peak plane of (110), (110) (200) and (004), respectively. The X-ray diffractograms of purified BC sample showed their amorphous nature. The distinguishing broad peaks at 3452.58 cm-1 for BC and 3356.14 cm-1 for PC indicates OH is stretching intra molecular H-bond for cellulose1. Sharp peaks appeared CH stretching at 2924.09 cm-1 in BC and 2900.94 cm- 1 in The pattern for BC revealed four main peaks were at 2 = 14.53, 16.78, 22.79 and 34.67, corresponding to the crystallographic peak plane of (110), (110) (200) and (004), respectively. The X-ray diffracts grams of purified BC sample showed their amorphous nature. The FTIR spectrum shown the distinguishing broad peaks at 3452.58 cm-1 for BC and 3356.14 cm-1 for PC indicate OH is stretching intermolecular H-bond for cellulose 1. Sharp peaks appeared CH stretching at 2924.09 cm-1 in BC and 2900.94 cm-1 in PC. Overall, these data suggested that the BC and PC samples were the typical profile of the cellulose I crystalline structure and is typical of cellulose isolated from other fiber sources. The present results proved that BC and PC have a similar chemical bond and functional groups. [ABSTRACT FROM AUTHOR]

• A novel porogen was used for constructing porous bacterial cellulose. • The size of Ca-alginate microparticles was flexibly variable through electrostatic spinning and pulverization. • The porous bacterial cellulose exhibited a well uniform and spherical macropore cellulose network. In an attempt to obtain bacterial cellulose (BC) with controllable pores, Ca-alginate particles were introduced into BC fermentation medium. Ca-alginate particles with different diameters were prepared through electrostatic spinning and pulverization. After removing the particles, a continuous and homogeneous network of pores with diameters around 5 μm, 20 μm, and 400 μm were presented inside BC hydrogel. Compared to native BC, the crystallinity, the surface area and water holding capacity (WHC) were all increased when the pore sizes around 5 μm, 20 μm. However, the porous BC with diameters around 400 μm showed poor performance in WHC and mechanical strength. This novel approach described in this paper introduced a new approach for creating controllable porous BC with user-defined control over the physical dimensions of the network, and slightly changed its structure. [ABSTRACT FROM AUTHOR]

In this study, effective microorganism (EM) was added into fermentation medium in static culture to enhance bacterial cellulose (BC) production by Acetobacter xylinum 23769 strain. According to SEM micrographs, BC pellicles from BC-Baikal EM1 show a smaller diameter and a relatively narrow diameter distribution compared to BC pellicles from Hestrin–Schramm (HS) medium. The BC-HS absorbed 90.5 times its dry weight of water. The water holding capacity increased to 132.5 for BC-Baikal EM1 medium compared to BC-HS. From the FT-IR spectra, BC samples exhibited a similar pattern. The crystalline indices of Baikal EM1-altered BC (66%) were lower than Baikal EM1-free BC (71%). [ABSTRACT FROM AUTHOR]

The aim of this study was to assess whether modified bacterial cellulose can be used for an artificial auricle skeleton. Introduction: The auricle is a part of the external ear. It consists of skin, cartilage, muscles and adipose tissue. The cartilage gives shape to the structure. There are several indications for reconstruction, such as congenital anomalies, mechanical injuries and burns, and a range of methods have been proposed for complete reconstruction of the auricle. Material and methods: A bacterial cellulose membrane, at least 25 mm in thickness, was produced in vitro by Acetobacter xylinum culture. The entire artificial human auricle skeleton was made to scale to allow its implantation into an animal model - Wistar rats. Forty rats were divided into four groups of 10 animals. Each group was assigned a different resection time: 14 days, 30 days, 90 days or 720 days. After each resection, an examination of the artificial skeleton and the tissues surrounding it was conducted. The surgical procedure was based on the Nagata technique. Results: Resection after 14, 30, 90 and 720 days shows progression of the healing process and integration of the artificial skeleton into the animal body. There are no signs of change in the shape or structure of the skeleton. Discussion: Several surgical techniques and biotechnological methods have been developed over the past few years to improve the results of facial reconstruction. Other approaches can be used to create auricle cartilage, based on scaffolds and chondrocytes. Conclusion: My findings indicate that modified bacterial cellulose can be used to form an effective artificial auricle which appears to maintain its shape and elasticity, with no signs of degradation. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Acetobacter xylinum synthesized BC using tobacco waste extract. • Nicotine was found to be inhibitory for the synthesis of BC. • BC production increased after nicotine removal by steam distillation at pH 9.0. • BC production reached 5.2 g/L using two-stage fermentation by adjusting pH. • BC obtained from TWE medium has similar properties to that from HS medium. Abstract In this study, bacterial cellulose (BC) was synthesized by Acetobacter xylinum ATCC 23767 using tobacco waste extract (TWE) as a carbon source. Nicotine was found to be an inhibitory factor for BC synthesis, but it can be removed at pH 9.0 by steam distillation. After removing nicotine, the BC production was 2.27 g/L in TWE prepared with solid-liquid (S-L) ratio at 1:10. To further enhance the BC production, two fermentation stages were performed over 16 days by re-adjusting the pH to 6.5 at 7 days, after the first fermentation stage was completed. Using this two-stage fermentation, the BC production could reach 5.2 g/L. Structural and thermal analysis by FE-SEM, FT-IR, XRD and TGA showed the properties of BC obtained from TWE were similar to that from Hestrin-Schramm (HS) medium. Considering the huge disposal tobacco waste in China, the present study provides an alternative methodology to synthesize BC. [ABSTRACT FROM AUTHOR]

Introduction: There is an increasing need for vascular prosthesis in dialysis medicine for the construction of arteriovenous (AV)-fistulas for dialysis access. The aims of this study were; a) to develop and validate a new experimental AV-fistula model for larger animals using grafts of bacterial cellulose (BC) between the common carotid artery and the external jugular vein; b) to observe the immediate and intermediate properties (macroscopic and angiographic patency and the macro- and micro thrombogenicity) of the grafts. Materials and Methods: As graftmaterial bacterial cellulose was used, produced around a preformed scaffold. Bacterial cellulose (BC) is a material produced by the bacteria acetobacter xylinum. A pilotstudy was conducted on 6 pigs to validate the animalmodel and the new graftmaterial. In the following survival study a BC-graft AV-fistula was constructed in 15 pigs. Results: In the pilot study, 5 out of 6 animals had a patent AV-fistula 4 hours after implantation. In the survival study, after 4 (n3) and 8 (n10) weeks an angiography was performed prior to explantation of the BC-graft. All grafts were occluded with a presumed platelet plug. We conducted an additional acute patch-test comparing the BC and expanded PolyTetraFluoro- Ethylene. A patch of BC and ePTFE was applied to the right and left common femoral artery respectively. At explantation three hours later, all BC-patches showed a thin gel like layer, most likely consisting of platelets, throughout the whole sur- face while the ePTFE-patch showed no, or minimal, signs of platelet adhesions. Conclusion: Theoretically the cellulose might be similar to autologous veins considering risk of infections and thrombo- genicity. The animal model and the graft material showed good potential in the pilot study. The survival study was discour- aging with the reason for occlusion still to be explained. Bacterial cellulose has a good potential but further development and studies need to be performed. [Arch Clin Exp Surg 2016; 5(2.000): 70-77]

Abstract: Cellulose nanofibrils are attractive as building blocks for advanced photonic, optoelectronic, microfluidic, and bio‐based devices ranging from transistors and solar cells to fluidic and biocompatible injectable devices. For the first time, an ultrastrong and ultratough cellulose film, which is composed of densely packed bacterial cellulose (BC) nanofibrils with hierarchical fibril alignments, is successfully demonstrated. The molecular level alignment stems from the intrinsic parallel orientation of crystalline cellulose molecules produced by Acetobacter xylinum. These aligned long‐chain cellulose molecules form subfibrils with a diameter of 2–4 nm, which are further aligned to form nanofibril bundles. The BC film yields a record‐high tensile strength (≈1.0 GPa) and toughness (≈25 MJ m−3). Being ultrastrong and ultratough, yet the BC film is also highly flexible and can be folded into desirable shapes. The BC film exhibits a controllable manner of alignment and is highly transparent with modulated optical properties, paving the way to enabling new functionalities in mechanical, electrical, fluidic, photonics, and biocompatible applications. [ABSTRACT FROM AUTHOR]

Abstract: To improve bacterial cellulose (BC) applications, researchers have expanded their efforts with BC productivity and its properties. The objectives of this study are to evaluate the possibility and efficacy of using extracted date syrup as a carbon source for Acetobacter xylinum 0416 in BC production in a static culture. The sugar content of extracted date syrup was identified by HPLC. Different concentrations of dates and different culturing times were tested. The produced BCs were characterized and their respective properties were compared with a BC produced from Hestrin and Schramm (HS) medium. The most effective BC amount was attained with 3% (w/v) date in the medium on day 8. The modified HS medium (DHS) increased production by 68% (P < 0.05). Morphological analysis by scanning electron microscopy revealed more disorganized arrangements in BC fiber obtained from DHS medium (BC‐DHS) than that from HS medium (BC‐HS). Thermogravimetric analysis revealed no significant changes in BC‐DHS thermostability compared to BC‐HS. However, the crystallinity of BC‐DHS improved (P < 0.05). The results of Fourier transform infrared spectroscopy demonstrated that the carbonyl group in BC‐DHS is more active than that of BC‐HS. Furthermore, the properties of BC‐DHS showed excellent potential for use in many applications. [ABSTRACT FROM AUTHOR]

Durian is one important tropical fruit with high nutritional value, but its shell is usually useless and considered as waste. To explore the efficient and high-value utilization of this agricultural and food waste, in this study, durian shell was simply hydrolyzed by dilute sulfuric acid, and the durian shell hydrolysate after detoxification was used for bacterial cellulose (BC) production by Gluconacetobacter xylinus for the first time. BC was synthesized in static culture for 10 days and the highest BC yield (2.67 g/L) was obtained at the 8th day. The typical carbon sources in the substrate including glucose, xylose, formic acid, acetic acid, etc. can be utilized by G. xylinus. The highest chemical oxygen demand (COD) removal (16.40%) was obtained at the 8th day. The highest BC yield on COD consumption and the highest BC yield on sugar consumption were 93.51% and 22.98% (w/w), respectively, suggesting this is one efficient bioconversion for BC production. Durian shell hydrolysate showed small influence on the BC structure by comparison with the structure of BC generated in traditional Hestrin-Schramm medium detected by FE-SEM, FTIR, and XRD. Overall, this technology can both solve the issue of waste durian shell and produce valuable bio-polymer (BC). [ABSTRACT FROM AUTHOR]

The gram-negative bacterium of Gluconacetobacter xylinum is widely used to produce high-quality cellulose in the form of complex strips in microfiber bundles on a commercial scale. In this study, the film-forming potential of bacterial cellulose in combination with polyvinyl alcohol (PVA, 5 % w / v) and Barhang seed gum (BSG, 0.5 % w/v) loaded with summer savory (Satureja hortensis L.) essential oil (SSEO) to prepare a new wound dressing was investigated. The X-ray diffraction (XRD), Fourier transform-infrared spectroscopy (FTIR), field emission-scanning electron microscopy (FE-SEM), and thermogravimetric analysis (TGA), and Brunauer-Emmett-Teller (BET) surface area, in-vitro antibacterial, and in-vivo wound healing activities were performed to assess the structure, morphology, stability, and bioactivity of biocomposite films. Results showed that the SSEO incorporation into the polymeric matrix yielded smooth and transparent composite film with excellent thermal resistance. A significantly robust antibacterial activity against gram-negative bacteria by the bio-film was found. The healing process on mice models revealed that the SSEO-loaded composite film had a promising potential for wound healing associated with improved collagen deposition and reduced inflammatory response. [ABSTRACT FROM AUTHOR]