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Abstract The present study describes the development of a polymeric matrix based on bacterial cellulose (BC) additivated with grape skin residue extract by in situ and ex situ methods, to [...]

The biosynthesis of bacterial cellulose (BC) is significantly influenced by the type of carbon source available in the growth medium, which in turn dictates the material's final properties. This study systematically investigates the effects of five carbon sources—raffinose (C18H32O16), sucrose (C12H22O11), glucose (C6H12O6), arabinose (C5H10O5), and glycerol (C3H8O3)—on BC production by Komagataeibacter hansenii. The varying molecular weights and structural characteristics of these carbon sources provide a framework for examining their influence on BC yield, fiber morphology, and network properties. BC production was monitored through daily measurements of optical density and pH levels in the fermentation media from day 1 to day 14, providing valuable insights into bacterial growth kinetics and cellulose synthesis rates. Scanning electron microscopy (SEM) was used to elucidate fibril diameter and pore size distribution. Wide-angle X-ray scattering (WAXS) provided a detailed assessment of crystallinity. Selected BC pellicles were further processed via freeze-drying to produce a foam-like material that maximally preserves the natural three-dimensional structure of BC, facilitating the incorporation and release of lidocaine hydrochloride (5%), a widely used local anesthetic. The lidocaine-loaded BC foams exhibited a sustained and controlled release profile over 14 days in simulated body fluid, highlighting the importance of the role of carbon source selection in shaping the BC network architecture and its impact on drug release profile. These results highlight the versatility and sustainability of BC as a platform for wound healing and drug delivery applications. The tunable properties of BC networks provide opportunities for optimizing therapeutic delivery and improving wound care outcomes, positioning BC as an effective material for enhanced wound management strategies. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a versatile material produced by microorganisms in the form of a hydrogel film with high water retention capacity, porosity, and mechanical strength. BC can incorporate and release substances, making it an interesting polymer for use in the cosmetic and biomedical industries. The aim of the present study was to evaluate the use of a bacterium for the production of cellulose films in which propolis extract was added in situ and ex situ (during and after membrane production, respectively) with promising use as a skincare product. The bacterium Gluconacetobacter hansenii was grown in standard Hestrin-Schramm (HS) medium as well as HS medium with propolis extract for 7 days. A radiolytic process with [sub.60]Co was investigated as a safe sterilization method. The average yield was 120.55 [+ or -] 2.40 g of cellulose/L. The polymeric system exhibited antioxidant activity (15.16% inhibition of oxidant activity) and high water-retention capacity (98.01 [+ or -] 0.17%). In conclusion, natural additives can provide the antioxidant characteristics of BC. Moreover, gamma irradiation proved to be an effective sterilization method, while maintaining the properties of the material. KEYWORDS biopolymer, cosmeceutical, cosmetics, Gluconacetobacter hansenii, polymer, 1 | INTRODUCTION The cosmetic industry makes wide use of chemicals synthesized from materials originating from the petrochemical industry. However, petroleum products are responsible for soil contamination, water pollution, and [...]

The high consumption of packaging has led to a massive production of waste, especially in the form of nonbiodegradable polymers that are difficult to recycle. Microbial cellulose is considered a biodegradable, low-cost, useful, ecologically correct polymer that may be joined with other biomaterials to obtain novel characteristics and can, therefore, be used as a raw material to produce packaging. Bagasse, a waste rich in plant cellulose, can be reprocessed and used to produce and reinforce other materials. Based on these concepts, the aim of the current research was to design sustainable packaging material composed of bacterial cellulose (BC) and sugarcane bagasse (SCB), employing an innovative shredding and reconstitution method able to avoid biomass waste. This method enabled creating a uniform structure with a 0.10-cm constant thickness, classified as having high grammage. The developed materials, particularly the 0.7 BC/0.3 SCB [70% (w/w) BC plus 30% (w/w) SCB] composite, had considerable tensile strength (up to 46.22 MPa), which was nearly thrice that of SCB alone (17.43 MPa). Additionally, the sorption index of the 0.7 BC/0.3 SCB composite (235.85 ± 31.29 s) was approximately 300-times higher than that of SCB (0.78 ± 0.09 s). The packaging material was also submitted to other analytical tests to determine its physical and chemical characteristics, which indicated that it has excellent flexibility and can be folded 100 times without tearing. Its surface was explored via scanning electron microscopy, which revealed the presence of fibers measuring 83.18 nm in diameter (BC). Greater adherence after the reconstitution process and even a uniform distribution of SCB fibers in the BC matrix were observed, resulting in greater tear resistance than SCB in its pure form. The results demonstrated that the composite formed by BC and SCB is promising as a raw material for sustainable packaging, due to its resistance and uniformity. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) can be chemically modified and combined with other materials to create composites with enhanced properties. In the medical field, biomaterials offer advantages, such as biocompatibility and sustainability, enabling improved therapeutic strategies and patient outcomes. Incorporating lidocaine into wound dressings offers significant potential benefits. In this study, transparent BC films were produced in situ with an undefined minimal culture medium with a yeast and bacteria co-culture system on black tea (Camellia sinensis) and white sugar medium for three days. Lidocaine was incorporated ex situ into the BC matrix, and the composite film was sterilized using gamma radiation. Drug-release studies showed a two-stage release profile, with an initial fast release (24.6%) followed by a slower secondary release (27.2% cumulative release). The results confirmed the incorporation of lidocaine into the BC, producing highly transparent films with excellent thermal stability, essential for the storage and transportation of wound dressings. This study highlighted BC properties and drug incorporation and release behavior. The findings contribute towards optimizing wound dressings with controlled drug release, showcasing the potential of transparent BC films as an effective platform for wound care and drug-delivery applications. [ABSTRACT FROM AUTHOR]

The textile industry is one of the largest in the world, being of a great economical impact in many countries. The high water consumption and large effluents production with high concentrations of chemical products and residual dyes are amongst the industry’s biggest environmental impacts. The application of biosurfactants (BS) in many processes in this industry is already established. However, its exploration in the effluent treatment stages can still be improved. Natural surfactants have diverse structure, are biodegradable, biocompatible, selective, and have good stability. They can be greatly explored in filtering processes. Bacterial cellulose (BC), a high purity biopolymer, is formed by a three-dimensional (3D) nanofibrillar network, with high water absorption capacity and high tensile strength. The present study aimed to evaluate, individually and in combination, the use of BS and BC both produced in media supplemented with industrial waste, aiming for its application in the treatment of textile effluents. The tests were carried out with synthetic effluents with navy blue dye at concentrations between 7.5 – 30.0 mg/L. BS was added to the effluent in the critical micelle concentration (CMC) of 1x CMC, 3 x CMC and 10 x CMC, to observe the agglutinating action. The BC pellicle with approximate thickness of 3 mm was evaluated as a filtering element. The color removal index of the treated effluent was determined through spectrometry as the parameter of effectiveness. The results showed an efficiency in color removal of up to 45 % solely with BC as a filtering agent and of 65 % when treated with BS before filtration with BC. The results demonstrate the potential of reducing the color parameter with the BS/BC association for a lowcost and sustainable filtration system to be applied in textile effluent treatment. [ABSTRACT FROM AUTHOR]

Bacterial cellulose (BC) is a natural polymer synthesized in a pure manner by different kinds of microorganisms. It is a material with a three-dimensional (3D) nanofibrillary network that has interesting chemical and mechanical properties. Due to its high polymeric degree and its characteristics, it can be applied in several technological fields, such as filtration membranes, packages, cosmetics, textile, and other industries. The usage possibility of agro-industrial residues as alternative nutrients source is a great economic advantage to not only lower BC production costs but also to improve its yield and diminish the disposal of such residues. This work used the bacteria Komagataeibacter hansenii UCP1619, which was cultivated on alternative cultivation media, which were modified based on the standard media Hestrim-Schramm (HS). The best media was selected according to its cost benefit and BC’s growth yield. The pellicles were obtained after 14 days incubation time. Flexibility and water holding capacity were calculated. It can be concluded that the production media modification with tomato extract resulted in a cost reduction of 76% on the used liquid media, with a great biocellulose production. This modification is ideal for its use in applications that require a denser fiber distribution, such as in emulsified effluent filtrations. [ABSTRACT FROM AUTHOR]

Fashion is considered to be one of the branches of world industry that most polluted and destroys the environment. Most of the damage caused by this segment comes from the production, manufacture, and synthetic dyeing of the fabrics. Regarding this concern, the usage of natural textiles, such as cotton, wool, and linen, has been growing in an attempt to reduce these impacts. However, even though these textiles are often considered ecologically sustainable, there is still great damage regarding their extensive land utilization, with effects that are often irreversible. Among the possibility of new textile biomaterials aiming at greater sustainability of the production chain, bacterial cellulose (BC) stands out, as a biotechnological polymer that has aroused industrial interest, due to its attractive properties for the sector. BC is a biodegradable polymer produced by microorganisms; therefore, it does not pollute the environment. Thus, the present study aimed to evaluate the use of BC as a bio textile, combined with natural dyes based on Eucalyptus (Eucalyptus globulus L.) and Onion (Allium cepa L.). The obtained BC membrane had high-water retention of 98.48 %. The behavior of dyed BC was compared to that of raw cotton and linen, which were also dyed with the same methods and dyes. Post-dyeing fabrics were evaluated for fixation and X-ray diffractometry (XRD). The pure matrices obtained a higher crystallinity index than after the dyeing process, demonstrating that the dye rearranged the matrices organization, resulting in better color fixation. Through the fixation tests, it was observed that the BC can be dyed effectively, like other natural textiles. Demonstrating that microbial biocellulose can also play the role of an attractive textile for the current industry with the importance of socioenvironmental awareness. [ABSTRACT FROM AUTHOR]

The biomaterial entitled BioMask presents itself as an ideal film to be used in skin that present inflammations in their hair follicles, which can affect various body regions. Intrinsic characteristics of bacterial cellulose (BC) are important and can aid with the aesthetic treatment in the dermocosmetic area. BC's film is hypoallergenic, nontoxic, has high water retention, high purity, flexibility, biocompatibility and biodegradability. When BC is produced in a sustainable way, it can become a fundamental rich raw material for cosmeceuticals. The BioMask is enriched with bioactive compounds of high efficacy to help the healing process of the skin. Natural extracts are incorporated into dermo cosmetic products for the purpose of moisturizing, perfuming, and aggregating medicinal properties. Propolis extract is a natural waxy substance, produced by bees from the resin of several plants. Chemically, it has the presence of polyphenols and many flavonoids and innumerable biological activities. Thus, medicinal products containing propolis in the composition are used in medical treatments, and satisfactory results can be observed in the healing process and the reduction of symptoms of inflammation. The BC film was produced in Hestrin-Schramm (HS) medium and then a 2 % propolis extract was incorporated in the obtained film. The film was characterized by XRD and TGA spectroscopy. The pellicles were sterilized and a prototype of the BioMask was done. The objective of this study was to develop a BioMask that helps in the healing of inflammations caused by acne. Due to BC's high-water content, its usage as an occlusive mask can also aid in skin hydration and enable the improvement of the texture of the treated skin. BioMask is considered a dermatological and cosmetic product for immediate consumption and disposal. Being used as a possibility of treatment for acne patients, it is expected a minimization of pain, improved skin hydration and acceleration in the healing process of the skin without much aesthetic damages and improving the self-esteem and quality of life of people who have acne. [ABSTRACT FROM AUTHOR]

The term cosmeceutical comes from the combination of cosmetics and pharmaceuticals, which has been emerged due to the CPC's market's (Cosmetics and Personal Care) necessity of combining body and skin care with products that has the usage of bioactive ingredients, ensuring a more sustainable development with a new kind of biotechnology. Regarding this idea, this project consisted on studying the usage of a bacterial cellulose (BC) producing bacteria, Glucanacetobacter hansenii, which has been cultivated in a media made out of juice from tropical fruit residue, used as a plant alternative for the production of a BC with beneficial characteristics for the skincare. The tropical fruit, with its enzymatic and non-enzymatic sites and its high nutrient and minerals content, contributes for the prevention of free radicals of the skin. Besides from serving as a support for incorporation of the active principles of tropical fruit, BC has high water activity when applied to the skin, helping to retain its natural moisture. For the experiments, the microorganism was cultivated on eleven different cultivation media, which were modified from the standard media HS (Hestrim-Schramm). The working media was selected according to its cost benefit and BC's growth yield. The experiments were performed after 10 days of the bacteria's cultivation on the media cited previously. With the obtained BC pellicle, both its water activity and ascorbic acid were quantified, and its mechanical properties were determined. A BC face mask was also constructed. It can be concluded that the addition of tropical fruit residue in the bacteria's cultivation media, grants ideal skin hydration characteristics to the BC pellicle, enabling the development of a new biotechnological product for the pharmaceutical and cosmetics industries. [ABSTRACT FROM AUTHOR]

Cellulose is the most abundant biopolymer on the planet and has a wide range of applications in different industrial sectors. Environmental preservation policies, on the other hand, promote the development of research to replace vegetable cellulose (VC), due to the fact that its production causes several damages to the environment. In this way, bacterial cellulose (BC) appears as a promising alternative to VC, since it differs from its vegetal similar mainly because it presents fibers of a nanometric character against the micrometric of the vegetable, which gives it excellent mechanical properties like greater purity, higher index of crystallinity, higher water absorption power and higher tensile strength. Thus, the present study was carried out for the development of a filter base on the use of BC membrane for the treatment of oily waters. BC membranes were initially produced in an alternative medium based on corn steep liquor (industrial waste) due to the fact that the standard production medium (HS) represents a high cost for the production of BC on an industrial scale, since is formulated with synthetic compounds. Then, wet BC membrane samples were purified and tested as filters for the separation of oily waters with oil concentrations of 10 ppm, 150 ppm and 230 ppm. The experiments were performed in triplicate and showed 100% removal of the oil present in all samples. Variables such as flow rate, filter diameter (25 mm, 50 mm, 110 mm) and production time of the membranes (6 and 10 days) were evaluated in a filtration system constructed in PVC. By showing that the filtration rate increases proportionally to the filter diameter, it decreases from the 6-day membrane to the 10-day membrane. The mean water mass present in both 6 and 10-day BC membranes exceeded 98%. The wet BC membranes presented satisfactory results in the mechanical assays, however the 10-day membrane supported 100% more in strength (N) than the 6-day film. The results obtained in this study showed the potential of this new nontoxic and efficient biodegradable material in the separation of water/oil mixtures generated in industrial environments. [ABSTRACT FROM AUTHOR]