Production of bacterial cellulose tubes for biomedical applications: Analysis of the effect of fermentation time on selected properties

Biofabrication with microbial cellulose: from bioadaptive designs to living materials

Nanocellulose is not only a renewable material but also brings functions that are opening new technological opportunities. Here we discuss a special subset of this material, in its fibrillated form, which is produced by aerobic microorganisms, namely, bacterial nanocellulose (BNC). BNC offers distinct advantages over plant-derived counterparts, including high purity and high degree of polymerization as well as crystallinity, strength, and water-holding capacity, among others. More remarkably, beyond classical fermentative protocols, it is possible to grow BNC on non-planar interfaces, opening new possibilities in the assembly of advanced bottom-up structures. In this review, we discuss the recent advances in the area of BNC-based biofabrication of three-dimensional (3D) designs by following solid- and soft-material templating. These methods are shown as suitable platforms to achieve bioadaptive constructs comprising highly interlocked biofilms that can be tailored with precise control over nanoscale morphological features. BNC-based biofabrication opens applications that are not possible by using traditional manufacturing routes, including direct ink writing of hydrogels. This review emphasizes the critical contributions of microbiology, colloid and surface science, as well as additive manufacturing in achieving bioadaptive designs from living matter. The future impact of BNC biofabrication is expected to take advantage of material and energy integration, residue utilization, circularity and social latitudes. Leveraging existing infrastructure, the scaleup of biofabrication routes will contribute to a new generation of advanced materials rooted in exciting synergies that combine biology, chemistry, engineering and material sciences.

Recent advancements in development and application of microbial cellulose in food and non-food systems

Microbial cellulose is a fermented form of very pure cellulose with a fibrous structure. The media rich in glucose or other carbon sources are fermented by bacteria to produce microbial cellulose. The bacteria use the carbon to produce cellulose, which grows as a dense, gel-like mat on the surface of the medium. The product was then collected, cleaned, and reused in various ways. The properties of microbial cellulose, such as water holding capacity, gas permeability, and ability to form a flexible, transparent film make it intriguing for food applications. Non-digestible microbial cellulose has been shown to improve digestive health and may have further advantages. It is also very absorbent, making it a great option for use in wound dressings. The review discusses the generation of microbial cellulose and several potential applications of microbial cellulose in fields including pharmacy, biology, materials research, and the food industry.

Recent advances and biomedical application of 3D printed nanocellulose-based adhesive hydrogels: A review

Nanocellulose-based tissue adhesives show promise for achieving rapid hemostasis and effective wound healing. Conventional methods, such as sutures and staples, have limitations, prompting the exploration of bioadhesives for direct wound adhesion and minimal tissue damage. Nanocellulose, a hydrolysis product of cellulose, exhibits superior biocompatibility and multifunctional properties, gaining interest as a base material for bioadhesive development. This study explores the potential of nanocellulose-based adhesives for hemostasis and wound healing using 3D printing techniques. Nanocellulose enables the creation of biodegradable adhesives with minimal adverse effects and opens avenues for advanced wound healing and complex tissue regeneration, such as skin, blood vessels, lungs, cartilage, and muscle. This study reviews recent trends in various nanocellulose-based 3D printed hydrogel patches for tissue engineering applications. The review also introduces various types of nanocellulose and their synthesis, surface modification, and bioadhesive fabrication techniques via 3D printing for smart wound healing.

Bacterial Cellulose Applied in Wound Dressing Materials: Production and Functional Modification - A Review

In recent years, the development of new type wound dressings has gradually attracted more attention. Bacterial cellulose (BC) is a natural polymer material with various unique properties, such as ultrafine 3D nanonetwork structure, high water retention capacity, and biocompatibility. These properties allow BC to be used independently or in combination with different components (such as biopolymers and nanoparticles) to achieve diverse effects. This means that BC has great potential as a wound dressing. However, systematic summaries for the production and commercial application of BC-based wound dressings are still lacking. Therefore, this review provides a detailed introduction to the production fermentation process of BC, including various production strains and their biosynthetic mechanisms. Subsequently, with regard to the functional deficiencies of bacterial cellulose as a wound dressing, recent research progress in this area is enumerated. Finally, prospects are discussed for the low-cost production and high-value-added product development of BC-based wound dressings.

Bacterial Nanocellulose Hydrogel: A Promising Alternative Material for the Fabrication of Engineered Vascular Grafts

Blood vessels are crucial in the human body, providing essential nutrients to all tissues while facilitating waste removal. As the incidence of cardiovascular disease rises, the demand for efficient treatments increases concurrently. Currently, the predominant interventions for cardiovascular disease are autografts and allografts. Although effective, they present limitations including high costs and inconsistent success rates. Recently, synthetic vascular grafts, made from artificial materials, have emerged as promising alternatives to traditional methods. Among these materials, bacterial cellulose hydrogel exhibits significant potential for tissue engineering applications, particularly in developing nanoscale platforms that regulate cell behavior and promote tissue regeneration, attributed to its notable physicochemical and biocompatible properties. This study reviews recent progress in fabricating engineered vascular grafts using bacterial nanocellulose, demonstrating the efficacy of bacterial cellulose hydrogel as a biomaterial for synthetic vascular grafts, specifically for stimulating angiogenesis and neovascularization.

Bacterial-Nanocellulose-Based Biointerfaces and Biomimetic Constructs for Blood-Contacting Medical Applications

Understanding the interaction between biomaterials and blood is critical in the design of novel biomaterials for use in biomedical applications. Depending on the application, biomaterials can be designed to promote hemostasis, slow or stop bleeding in an internal or external wound, or prevent thrombosis for use in permanent or temporary medical implants. Bacterial nanocellulose (BNC) is a natural, biocompatible biopolymer that has recently gained interest for its potential use in blood-contacting biomedical applications (e.g., artificial vascular grafts), due to its high porosity, shapeability, and tissue-like properties. To promote hemostasis, BNC has been modified through oxidation or functionalization with various peptides, proteins, polysaccharides, and minerals that interact with the coagulation cascade. For use as an artificial vascular graft or to promote vascularization, BNC has been extensively researched, with studies investigating different modification techniques to enhance endothelialization such as functionalizing with adhesion peptides or extracellular matrix (ECM) proteins as well as tuning the structural properties of BNC such as surface roughness, pore size, and fiber size. While BNC inherently exhibits comparable mechanical characteristics to endogenous blood vessels, these mechanical properties can be enhanced through chemical functionalization or through altering the fabrication method. In this review, we provide a comprehensive overview of the various modification techniques that have been implemented to enhance the suitability of BNC for blood-contacting biomedical applications and different testing techniques that can be applied to evaluate their performance. Initially, we focused on the modification techniques that have been applied to BNC for hemostatic applications. Subsequently, we outline the different methods used for the production of BNC-based artificial vascular grafts and to generate vasculature in tissue engineered constructs. This sequential organization enables a clear and concise discussion of the various modifications of BNC for different blood-contacting biomedical applications and highlights the diverse and versatile nature of BNC as a natural biomaterial.

Bacterial cellulose-based composites for nerve tissue engineering

Nerve injuries and neurodegenerative disorders are very serious and costly medical challenges. Damaged nerve tissue may not be able to heal and regain its function, and scar tissue may restrict nerve cell regeneration. In recent years, new electroactive biomaterials have attracted widespread attention in the neural tissue engineering field. Bacterial cellulose (BC) due to its unique properties such as good mechanical properties, high water retention, biocompatibility, high crystallinity, large surface area, high purity, very fine network, and inability to absorb in the human body due to cellulase deficiency, can be considered a promising treatment for neurological injuries and disorders that require long-term support. However, BC lacks electrical activity, but can significantly improve the nerve regeneration rate by combining with conductive structures. Electrical stimulation has been shown to be an effective means of increasing the rate and accuracy of nerve regeneration. Many factors, such as the intensity and pattern of electrical current, have positive effects on cellular activity, including cell adhesion, proliferation, migration and differentiation, and cell-cell/tissue/molecule/drug interaction. This study discusses the importance and essential role of BC-based biomaterials in neural tissue regeneration and the effects of electrical stimulation on cellular behaviors.

Preparation, Characterization, and Biological Features of Cactus Coated Bacterial Cellulose Hydrogels

The current study was aimed at developing BC-Cactus (BCC) composite hydrogels with impressive mechanical features for their potential applications in medical and environmental sectors. BCC composites hydrogels were developed through cactus gel coating on a never dried BC matrix. The FE-SEM micrographs confirmed the saturation of BC fibrils with cactus gel. Additionally, the presence of various functional groups and alteration in crystalline behavior was confirmed through FTIR and XRD analysis. Mechanical testing illustrated a three-times increase in the strain failure and an increase of 1.6 times in the tensile strength of BCC composite. Absorption capabilities of BCC were much higher than pure BC and it retained water for a longer period of time. Additionally, the rewetting and absorption potentials of composites were also higher than pure BC. The composite efficiently adsorbed Pb, Zn, Cu, and Co metals. Biocompatibility studies against human HaCat cell line indicated much better cell adhesion and proliferation of BCC compared to BC. These findings advocate that the BCC composite could find applications in medical, pharmaceutical and environmental fields.