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Wound dressings are used in order to expedite wound healing process and prevent infection. An ideal dressing has unique characteristics such as retaining moisture in the wound bed, proper absorption of wound secretion, heat retaining, appropriate exchange of air and water vapor, and prevents secondary infection and activation of process improvement. Traditional dressings made of cotton have some weak points, including drying the wound, sticking to it and sensitivity in some people as well. In addition, these are the adverse effects on the healing process, causing bad feeling in the wound and remove the dressing damage to the wound.
Although cellulose is frequently derived from plant, but also can be synthesized by a variety of microorganisms such as bacteria, algae and fungi (Wen-Chun, Chun-Chieh, Hsiu-Jen, Chao-Ming, & Shan-hui, 2013). Biocellulose is a purified form of extracellular polysaccharide composed of long non-aggregated nanofibrils that is produced by several of Gram-negative bacteria using glucose (Kwak et al., 2015). Many strains of bacteria possess the ability to produce cellulose at the surface of a medium containing carbon and nitrogen as food source. These include Agrobacterium, Sarcina, Rhizobium and Acetobacter (Gea et al., 2011). Some of the bacteria used for production of cellulose include -proteobacteria, -proteobacteria, -proteobacteria (Gram-negative) and Gram-positive bacteria (Rehm, 2010). In the case of Gram-negative bacteria, cellulose is mainly produced by bacteria of the Gluconoasetobacter genus. These bacteria are strictly aerobic bacteria and capable of producing cellulose in the form of extracellular, in terms of static media (at the air-environment interface) at a temperature between 25 and 30 OC and the pH between 4 and 7 (Castro et al., 2012). During the biosynthesis of cellulose, the bacteria uses different combinations in the Hestrin-Schramm (HS) environment (Schramm and Hestrin, 1954). Probably Gluconacetobacter xylinus (formerly Acetobacter xylinum) is one of the most prevalentlyused sorces of bacterial cellulose; however, recently we have reported that Gluconacetobacter sacchari produces bacterial cellulose in very high yields (Trovatti, Serafim, Freire, Silvestre, & Neto, 2011).
Bacterial cellulose can be manufactured in the laboratory, and is also produced in the preparation of foods, such as nata de coco, an indigenous sweet confectionary found in East Asia (Abeer, Amin, & Martin, 2014).
Cellulose is composed of glucose monomers linked by (1–4) glycosidic linkages, and (C6H10O5) n is its chemical formula (Sheykhnazari, Tabarsa, Ashori, Shakeri, & Golalipour, 2011). However bacterial cellulose and plant cellulose have the same chemical formula, but plant cellulose includes many impurities such as hemicelluloses and lignin which are difficult to eliminate, while bacterial cellulose is free from these impurities (Jung, Park, & Chang, 2005). For this reason, bacterial cellulose is very much pure and has excellent degree of polymerization and great crystalinity (Kamarudin et al., 2013). With the ultra-fine network structure, bacterial cellulose displays unique phisico chemical properties such as high tensile strength, and water absorption capacity (Keshk & Sameshima, 2006).