Bacterial cellulose medical applications

The kind of polysaccharides that are isolated from different bacteria are as follows Alginate, a linear copolymer with (l-4)-linked p-D-mannuronate and its a-L-guluronate residues that is produced by two bacterial genera Pseudomonas species and Azotobacter vinelandii [4]. Bacterial alginates are useful for the production of micro- or nanostructures suitable for medical applications. Cellulose, a p (1—>4) linked D-glucose unit obtained from Acetobacter xylinum. Cellulose of plant origin is usually impure as it contains... 

Currently cellulose (exopolysaccharide) and polyhydroxyalkonates are the most important bacterial polymers which can be profitably used as polymeric material for industrial and medical applications. But it seems to be particularly difficult to achieve a quantitative upgrading of the corresponding extraction, biotechnology and tailor-made synthesis for substantial production at lower prices. Hence, the exploitation of these polymers in various applications will be very difficult until this situation is resolved. Indeed, much awaited is the development of methodologies to increase production of these polymers at affordable prices for more utility. 

Nanocellulose, such as that produced by the bacteria Gluconacetobacter xylinus (bacterial cellulose, BC), is an emerging biomaterial with great potential in several applications. The performance of bacterial cellulose stems from its high purity, ultra-fine network structure and high mechanical properties in the dry state [114]. These features allow its applications in scaffold for tissue regeneration, medical applications and nanocomposites. A few researchers have used bacterial cellulose mats to reinforce polymeric matrices and scaffolds with wound healing properties [115-121]. BC is pure cellulose made by bacterial fabrication via biochemical... 

Cienchanska, D. Multifunctional bacterial cellulose/chitosan composite materials for medical applications. Fibres Text. East Eur. 12, 69-72 (2004)... 

Medical Application of Bacterial Cellulose 10.5.1 Human Medicine... 

However, in the last decade the main application of bacterial cellulose has been in the biomedical materials field [13,46,55-57], Due to its unique nanostructure and properties, microbial cellulose is a nattnal candidate for numerous medical and tissue-engineered apphcations. In fact, much work has already been focused on designing ideal biomedical devices from BNC, such as artificial skin, blood vessels, cornea, urethra, bone, cartilage, porcine knee menisci, and heart valve prosthesis as well as deliveries of drug, hormone and protein [58-62], Figure 2,5 illustrates some of the prospects for the various biomedical applications of BNC-based materials. 

The results presented here refer specifically to membranes synthesized by Bionext s strain. Bionext is a Brazilian company that produces bacterial cellulose for medical applications. At this company, bactaial cellulose wet membranes are dried by compression and heating, a process that confers unique texture charactaistics. 

The use of bacterial cellulose in medical prosthesis is exciting, considering the perspectives of applications in cardiac bypass surgery and self-transplanted derivation vessels [23]. 

The properties of PVA-C summarized and reviewed thus far demonstrate many of the desirable properties that make it the material of choice for a broad range of biomedical applications. Using the fi eeze-thaw cycling procedure, PVA-C can be prepared with both tunable mechanical properties and diffusion properties. With the addition of biocompatible nanofillers such as bacterial cellulose and chitosan, the range of these properties can be further broadened. The diffusion properties and some applications of PVA-C for controlled release and delivery have already been covered (see Sect. 3.2). The focus of this section will be on the use of PVA-C as a material for medical devices. 

The main aim of this contribution is to present various approaches to the preparation of nanocellulosic materials from plant sources. The focus is on the extraction and investigation of microfibrillated cellulose (MFC) in particular however, to put this topic in context, cellulose whiskers and bacterial cellulose are also discussed in particular sections of the text and applications of nanocellu-losics in the animal body for the development of medical devices such as artificial blood vessels, and the application of bacterial nanocellulose as animal woimd dressings and cosmetic tissues. Therefore, this chapter has brought together a variety of areas from chemistry, medicine, and biotechnology. 

Differing from wood pulp cellulose, cellulose produced by acetic acid bacteria is devoid of contaminating polysaccharides such as hemicellulose and lignocellulose. The isolation and purificadmi of bacterial cellulose are therefore relatively simple processes. Because of its high purity, hydrophiUcity, structure-forming potential, chirahty, and biocompatibility, bacterial cellulose offers many possible applications in medical use. 

Referring to microbial cellulose applications, bacterial nanocellulose has proven to be a remarkably versatile biomaterial with use in paper products, electronics, acoustic membranes, reinforcement of composite materials, membrane filters, hydraulic fracturing fluids, edible food packaging films, and due to its unique nanostructure and properties, in numerous medical and tissue-engineered applications (tissue-engineered constructs, wound healing devices, etc). 

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