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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., (© 2024 International Union of Biochemistry and Molecular Biology, Inc.)

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 2 3 -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%., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Microcapsules made of synthetic polymers are used for the release of cargo in agriculture, food, and cosmetics but are often difficult to be degraded in the environment. To diminish the environmental impact of microcapsules, we use the biofilm-forming ability of bacteria to grow cellulose-based biodegradable microcapsules. The present work focuses on the design and optimization of self-grown bacterial cellulose capsules. In contrast to their conventionally attributed pathogenic role, bacteria and their self-secreted biofilms represent a multifunctional class of biomaterials. The bacterial strain used in this work, Gluconacetobacter xylinus , is able to survive and proliferate in various environmental conditions by forming biofilms as part of its lifecycle. Cellulose is one of the main components present in these self-secreted protective layers and is known for its outstanding mechanical properties. Provided enough nutrients and oxygen, these bacteria and the produced cellulose are able to self-assemble at the interface of any given three-dimensional template and could be used as a novel stabilization concept for water-in-oil emulsions. Using a microfluidic setup for controlled emulsification, we demonstrate that bacterial cellulose capsules can be produced with tunable size and monodispersity. Furthermore, we show that successful droplet stabilization and bacterial cellulose formation are functions of the bacteria concentration, droplet size, and surfactant type. The obtained results represent the first milestone in the production of self-assembled biodegradable cellulose capsules to be used in a vast range of applications such as flavor, fragrance, agrochemicals, nutrients, and drug encapsulation.

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., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Aims: To offset the negative effects of aeration on bacterial cellulose (BC) production by acetic acid bacteria using enmeshed cellulose microfibrils (CM) on luffa sponge matrices (LSM)., Methods and Results: The CM were enmeshed on LSM (LSM-CM). The optimal amount of LSM-CM was determined for BC production under aerated conditions. Without LSM-CM, no BC was produced in seven out of nine production cycles at the highest aeration rate (9 l min -1 ). However, with 0·5% LSM-CM and an aeration rate of 3 l min -1 , a satisfactory oxygen transfer coefficient was achieved, and also a good yield of BC (5·24 g l -1 ). Moreover, the LSM-CM was able to be recycled through nine consecutive BC production cycles. The highest BC yields (from 5·8 ± 0·4 to 6·6 ± 0·4 g l -1 ) were associated with high bacterial biomass and this was confirmed by scanning electron microscopy., Conclusions: We confirm that LSM-CM works well as a starter. Microenvironments low in dissolved oxygen within the matrices of LSM-CM are important for BC production under aeration conditions., Significance and Impact of the Study: The LSM-CM provides a microenvironment which offsets the negative effects of aeration on BC production. A sustainable, economic process for mass BC production is described using recycled LSM-CM with aeration., (© 2016 The Society for Applied Microbiology.)

Repeated photolithographic and etching processes allow the production of multileveled polymer microstructures that can be used as templates to produce bacterial cellulose with defined surfaces on demand. By applying this approach, the bacterial cellulose surface obtains new properties and its use for culturing neural stem cells cellulose substrate topography influences the cell growth in a defined manner., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The work is aimed to investigate the suitability of waste water of candied jujube-processing industry for the production of bacterial cellulose (BC) by Gluconacetobacter xylinum CGMCC No.2955 and to study the structure properties of bacterial cellulose membranes. After acid pretreatment, the glucose of hydrolysate was higher than that of waste water of candied jujube. The volumetric yield of bacterial cellulose in hydrolysate was 2.25 g/L, which was 1.5-folds of that in waste water of candied jujube. The structures indicated that the fiber size distribution was 3-14 nm in those media with an average diameter being around 5.9 nm. The crystallinity index of BC from pretreatment medium was lower than that of without pretreatment medium and BCs from various media had similar chemical binding. Ammonium citrate was a key factor for improving production yield and the crystallinity index of BC., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Bacterial cellulose (BC) is a biocompatible hydrogel with a three-dimensional (3-D) structure formed by a dense network of cellulose nanofibers. A limitation of using BC for applications in tissue engineering is that the pore size of the material (∼0.02-10μm) is smaller than the dimensions of mammalian cells and prevents cells from penetrating into the material and growing into 3-D structures that mimic tissues. This paper describes a new route to porous bacterial cellulose (pBC) scaffolds by cultivating Acetobacter xylinum in the presence of agarose microparticles deposited on the surface of a growing BC pellicle. Monodisperse agarose microparticles with a diameter of 300-500μm were created using a microfluidic technique, layered on growing BC pellicles and incorporated into the polymer as A. xylinum cells moved upward through the growing pellicle. Removing the agarose microparticles by autoclaving produced BC gels containing a continuous, interconnected network of pores with diameters ranging from 300 to 500μm. Human P1 chondrocytes seeded on the scaffolds, replicated, invaded the 3-D porous network and distributed evenly throughout the substrate. Chondrocytes grown on pBC substrates displayed a higher viability compared to growth on the surface of unmodified BC substrates. The approach described in this paper introduces a new method for creating pBC substrates with user-defined control over the physical dimensions of the pore network, and demonstrates the application of these materials for tissue engineering., (Copyright © 2014 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)

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]

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]

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]

Durian seeds are a waste product from durian fruit. Durian seeds are often used by people as the main ingredient in making bread and cakes. However, the use of durian seeds as the main ingredient in making nata has never been done. Nata is extracellular cellulose obtained from the activity of the bacteria Acetobacter xylinum. The nata that is often found is nata de coco made from coconut water as the main ingredient. This research aims to look at the formation of nata de durio from durian seeds. The results showed that different dry weights of durian seeds did not affect the thickness of the Nata De Durio formed. The thickness of Nata De Durio on days 7 and 14 was highest at a dry weight of 250 grams of durian seeds with an average of 0.4 and 0.5 cm and the lowest was at a dry weight of 100 grams of durian seeds with an average of 0. 3 and 04 cm. Conclusion: The difference in dry weight of durian seeds does not affect the thickness of Nata De Durio. However, the dry weight of 250 gram durian seeds has a better Nata De Durio thickness compared to the dry weight of 100 grams and 200 grams of durian seeds. [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]

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]

Cellulose produced by fermentation of acetic acid bacteria has high tensile strength. Meanwhile, cellulose derived from wood, which is abundant in nature, has a limit in strength. In this work, delignified wood veneer was immersed in Acetobacter xylinum culture medium to self-assemble bacterial cellulose into wood pores. Then the process was continued with a heating press. It makes the material denser and causes hydrogen bonds to form between the cellulose fibers. This study observed the densified hybrid veneer for the period of bacterial fermentation and impregnation of resin stabilization in tensile strength and dynamic mechanical analysis (DMA). The densified hybrid veneer of bacterial cellulose with resin impregnation had the maximum tensile strength after 7 days of fermentation. The DMA test showed that a densified hybrid veneer of bacterial cellulose stabilized with resin has a good ability to store cyclic energy and a damping factor that increases with temperature. [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]

Copyright of China Brewing is the property of China Brewing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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]

Copyright of Polimery is the property of Industrial Chemistry Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Bacterial cellulose (BC), a biopolymer, is synthesized by BC-producing bacteria. Almost all producing strains are classified in the family Acetobacteraceae. In this study, bacterial strain P285 was isolated from contaminated honey wine in a honey factory in northern Thailand. Based on 16S rRNA gene sequence identification, the strain P285 revealed 99.8% identity with Komagataeibacter maltaceti LMG 1529 T. K. maltaceti P285 produced the maximum BC production at 20–30 °C and an initial media pH of 9.0. The highest BC production in modified mineral salt medium (MSM) was exhibited when glucose (16%, w/v) and yeast extract (3.2%, w/v) were applied as carbon and nitrogen sources, respectively. When sugarcane (8–16%, w/v) or honey (ratio of honey to water = 1: 4) supplemented with yeast extract was used, the BC production was greater. The characterization of BC synthesized by K. maltaceti P285 was undertaken using scanning electron microscopy (SEM) and Fourier transform infrared (FTIR) spectrometry. Meanwhile, X-ray diffraction results confirmed the presence of crystalline cellulose (2θ = 18.330, 21.390 and 22.640°). The maximum temperature of BC degradation was observed at 314 °C. Tensile properties analysis of hydrated and dried BC showed breaking strength of 1.49 and 0.66 MPa, respectively. These results demonstrated that K. maltaceti P285 has a high potential for BC production especially when grown in high initial media pH. Therefore, the strain would be suitable as an agent to make BC, the value-added product in the related factories. [ABSTRACT FROM AUTHOR]

The current study focuses on the fabrication of a mixed chemical colorimetric pH dye‐based indicator to monitor the freshness of ready‐to‐cook (RTC) idli batter stored under ambient conditions. The base of the indicator label was created using Acetobacter xylinum culture for the fabrication of a bacterial cellulose (BC) membrane film, and the characteristics of the developed film were analysed. Scanning electron microscopy identified the presence of a cellulose fibrils network and Fourier Transform–infrared spectroscopy indicated the presence of an amine group at wavenumber 1642 cm−1 on the developed BC film. Differential scanning calorimetry analysis identified the glass transition, onset, melting and end set melt temperatures as −30.3, 42.2, 85.6 and 105.9°C, respectively, and enthalpy as 209.2 Jg−1. The tensile strength of the developed base layer was found to be low at 27.11 ± 0.05 MPa. The developed base layer was coated with mixed colorimetric pH dyes of bromothymol blue and methyl red in a ratio of 2:3. The fabricated mixed colorimetric indicator label reacted as the carbon dioxide concentrations in the headspace increased from 0.15% ± 0.05% to 17.64% ± 0.11% (v/v) for up to 24 hours, and displayed a colour change of yellow for fresh to reddish orange for spoiled RTC idli batter stored under ambient conditions. [ABSTRACT FROM AUTHOR]

Bacterial cellulose is one of the widely discussed biomaterials due to its unique physical, mechanical and chemical characteristics. In this research, bacterial cellulosic film (BCF) was developed using Acetobacter xylinum strain in green tea as a source of carbon under static culture conditions. The developed BCF was evaluated for their morphological properties using a scanning electron microscope and the approximate fiber diameter noted as 38–40 nm. The purity of the cellulose evaluated through an X-ray diffraction method identified that the developed cellulose is Iα rich – triclinic type with 89.61% of crystallinity. The thermal behavior of the BCF was evaluated using TGA and DSC. The results indicated that the major weight loss occurred from 250 to 500°C. The glass transition temperature (Tg) of the developed BCF was very high and it was 165°C. Concerning the mechanical properties, the BCF had lower tensile strength (13.82 Kgf/Cm2), Elongation (10.13 mm) and air (19.72 cm3/cm2/sec) and water vapor permeability value (151 g/m2/day) than the woven cotton fabric. However, the water absorbency (0.7 s) and water holding capacity (320%) are superior to the cotton fabric. The contact angle of the BCF was noted around 28.53°, which is an indication of the higher hydrophilic nature of the BCF. These results provide an insight into the potential applications of bacterial cellulosic material in the apparel and textile sector. [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. [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]

This study was designed to evaluate the effects of cellulose membranes produced by Acetobacter xylinum bacteria, after enrichment of the growth media with Alzahdy palm dates syrup to enhance cellulose production for reducing the contamination of locally-produced white cheese with pathogenic bacteria. Cellulose was vitally activated by incubation with both probiotics Lactobacillus acidophilus and Lactobacillus plantarum and the effectiveness of the produced cellulose membranes was measured by studying six characteristics: elongation, tensile strength, membrane rupture, permeability to oxygen, permeability to water vapor, and thickness (mm). The produced membranes showed remarkable functionality and characteristics for all studied tests. The results indicate that the cellulose membranes showed high antibacterial activity after incubation with Lactobacillus acidophilus and Lactobacillus plantarum for 24 and 48 hours against five different pathogenic bacteria, namely E. coli, S. aureus, Pseudomonas sp., B. cereus and S. typhymurim. Moreover, a positive result was obtained by reducing the number of these pathogenic bacteria after treating the white cheese with the produced cellulose membranes. [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]

In this study, an innovative in situ green strategy was applied to prepare bacterial cellulose/silver nanocomposites using green tea as a substrate for the fermentation of Acetobacter xylinum bacteria and a reducing agent for the in situ synthesis of silver nanoparticles. The samples were analyzed by different characterization tests including field emission scanning electron microscopy (FESEM), X‐ray diffraction analysis (XRD), UV–vis spectroscopy, atomic absorption spectroscopy, and ATR. The results indicated the excellent antibacterial activities with 100% bacterial reduction percentage and inhibition zones of 2.6 and 2.8 cm against S. aureus and E. coli, respectively. Moreover, water absorption percentage and vertical wicking measurements supported the hydrogel properties of the prepared bio‐cellulose/silver nanocomposites. Finding of this research suggested the potential of the proposed green route for preparing antibacterial BC which can be regarded as a candidate for future wound healing applications. [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]

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]

Eco-friendly materials production from industrial wastes and renewable raw materials is being promoted for green construction applications. Therefore, considerable value can be added by combining green chemistry with microbial biotechnology to construct improved and far better, biologically stable, and compatible materials. For this purpose, herein, Schizophyllum commune IBL-06 was exploited for the production of ligninolytic enzymes (MnP, LiP, and Lac). This in-house extracted enzymatic consortium was used for the delignification of pristine rice husk. The enhanced level of delignification (40.35%) was achieved with maximum cellulose exposure (from 32 to 72%). The delignified rice husk was further reinforced with bacterial cellulose from Acetobacter xylinum. Subsequently, biocomposites were prepared from both pristine and bacterially treated rice husk using compression molding technique. Glycerol/maleic anhydride combination was used as a plasticizer/compatibilizer and chitosan (10 wt.%) as a filler for newly developed biocomposite specimens. The newly synthesized biocomposite specimens were characterized using different imaging and analytical techniques including scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. The characterization studies of newly developed biocomposites revealed significant improvement in morphological and mechanical properties of biocomposites. In addition, moderate increase in water uptake capacity was also observed due to the presence of hygroscopic filler among polymer matrix. In conclusion, the improved characteristics of newly developed biocomposites based on bacterial cellulose-reinforced delignified rice husk-PVA using chitosan filler suggest high throughput of enzymatic treatment for several industrial and biotechnological sectors. [ABSTRACT FROM AUTHOR]

To reduce the incidence of infection after craniocerebral operation, a type of bacterial cellulose, which can be used as a promising vehicle for the sustained release of vancomycin bacterial cellulose, was implanted in the rabbit with a dural defect. We manufactured artificial dura mater using bacterial cellulose that was fermented and incubated in Acetobacter xylinum. After bacterial cellulose membrane and vancomycin were heated to boiling in anhydrous ethanol, the decompressive, antimicrobial nature, physical properties, drug release in vitro and bacteriostasis of sustained release of vancomycin were tested. Then, the inflammatory effects and histocompatibility of both materials were examined by immunohistochemistry, real-time polymerase chain reaction, and Western blot. It shows that the sustained release of vancomycin bacterial cellulose has good elasticity and pressure compliance. Sustained release of vancomycin bacterial cellulose can release vancomycin smoothly and slowly in normal saline from 12 to 203 h. The concentration increases at first for 131 h and then remains unchanged with another 72 h. Sustained release of vancomycin bacterial cellulose can inhibit the colon formation of Staphylococcus aureus for about 120 h. The antibacterial tests showed that sustained release of vancomycin bacterial cellulose can inhibit the colon formation of S. aureus for about 120 h, while control standard paper can inhibit the colon formation of S. aureus for only 72 h. The levels of inflammatory cytokines such as IL-6, IL-1β, and tumor necrosis factor-α along with cyclooxygenase-2 and inducible nitric oxide synthase were higher in the normal bacterial cellulose group than the sustained release of vancomycin bacterial cellulose group seven days after implantation. These data indicated that the sustained release of vancomycin bacterial cellulose can improve the central system infection after implantation effectively. [ABSTRACT FROM AUTHOR]

Bacterial cellulose or Nata is produced using pineapple waste as substrate for the fermentation process by Acetobacter xylinum. This study was aimed to optimize the production of bacterial cellulose in static and agitated condition. Production of bacterial cellulose in agitated condition has been performed at different rpm, with and without adding micro particles. The fermentation conditions were set at pH 5.0 and 28 °C. The highest bacterial cellulose formation is obtained from agitated condition with additional micro particles at 120 rpm whereas the bacterial cellulose weight is increased by 70.23 % compared to the static condition. The addition of microparticles helped in increasing the bacterial cellulose formation by 15.19 %. From the optimization using Design Expert®, yeast extracts and potassium dihydrogen phosphate (KH2PO4) are the most significant factors affecting the bacterial cellulose production. From the results, the optimum formulation for bacterial cellulose production from pineapple waste as medium were yeast extract 6 g, sucrose 20 g, bactopepton 1.49 g and KH2PO4 1.08 g for 176.47 g (wet weight) of bacterial cellulose production. [ABSTRACT FROM AUTHOR]

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]

We discuss microbial cellulose (MC) produced by Acetobacter Xylinum and its metabolism related to the bacterium body structure on a basis of knowledges obtained by the small-angle scattering method with combining different spectrometers. MC is a supra-molecule system impregnated with a huge amount of water about 99% by weigh. In the previous literature [ Eur. Phys. J. E , 2008 and Macromol. Symp. 2009], we elucidated that 90% of total water is accumulated in non-crystalline bundle causing concentration fluctuations. In this paper, we develop our arguments by newly adding the knowledges on (i) the hierarchy in a bacterium body studied by SANS & USANS and (ii) the non-crystalline local structure in as-produced MC in a culture solution, confirmed by neutron diffraction with polarization analyses. As a control to emphasize the peculiarity of MC, we compare MC to a synthetic polymer gel of poly(N -isopropylacrylamide) (PNIPAAm) in a swollen state. Consequently, we conclude that a mechanism of excellent water absorption found for MC is attributed to capillarity related to hierarchically preserved non-crystalline domains, whereas tight hydration onto a monomer unit via a hydrogen bond is crucial to result in high water absorption for the PNIPAAm gel. Image 1 • In the previous literatures [ Eur. Phys. J. E , 2008 and Macromol. Symp. 2009], we elucidated that 90% of total water is accumulated in non-crystalline bundle in microbial cellulose (MC) produced by Acetobacter Xylinum. • In this paper, we developed our arguments by newly adding the knowledges on (i) the hierarchy in a bacterium body studied by SANS & USANS and (ii) the non-crystalline local structure in as-produced MC in a culture solution, confirmed by neutron diffraction with polarization analyses. • As a control, we studied a synthetic polymer gel of poly(N -isopropylacrylamide) (PNIPAAm) in a swollen state. • A mechanism of excellent water absorption of MC is attributed to capillarity related to hierarchically preserved non-crystalline domains, whereas tight hydration onto a monomer unit via a hydrogen bond is crucial for high water absorption for the PNIPAAm gel. [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]

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]