الفهرس 
Literature reviewOnly 14 pages are availabe for public view
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Abstract
Cellulose is considered as the most abundant and cheap carbohydrate polymer in the world traditionally which extracted normaly from plants. It is consists of a linear polysaccharide homo-polymer of D-glucose with a disaccharide repeat unit consisting of two glucose residues joined by a β (1–4) glycosidic bond. Its chemical formula is (C6H10O5)n. Plant cellulose contain hemicellulose and lignin which considered as impurities with cellulose and it has to undergo unhealthy chemical treatments to obtain the pure product.
Many bacterial strains were able to produce bacterial cellulose but Acetobacter xylinum was founded to be the most efficient BC producer. Bacterial cellulose exhibits numerous great properties than plant cellulose as unique nanostructure, oxygen permeability, biocompatibility, water-binding capability, adaptability to the living body, high degree of crystallinity, degree of polymerization and biodegradability. Bacterial cellulose used for different application as tissue engineering of cartilage and synthetic blood vessels and different biomedical applications.
Different studies were done to stimulate BC productivity and our study focused on isolation of potent cellulose-producing bacteria; optimization of culture conditions for bacterial cellulose production and trails to growth of cellulose- producing bacteria on low cost raw materials.
Twenty seven samples of rotten fruits, rotten vegetables and soil samples were used for isolation of cellulose- producing bacteria. Only one isolate MH1 (isolated from local apple) showed the ability to produce cellulose pellicle on H.S medium as the pellicle withstand NaOH treatment. This isolate was selected for further identification and optimization for cellulose production.
Different morphological, biochemical and 16S rRNA testes were done for identification of an isolate MH1 and the results showed that the bacterial isolate MH1 was identified as Komagataeibacter hansenii and coded it as Komagataeibacter hansenii (MH1).
Five media were tested for BC production by Komagataeibacter hansenii (MH1) strain and the results showed that, GAM was the best medium with 1.29 g/l BC dry weight production.
The results of carbon source optimization showed that, sucrose was the best carbon source with 1.33 g/l BC dry weight production. Also different sucrose concentration were tested to select the best concentration for BC production and the results indicated that, 2% sucrose was the best concentration on modified GAM medium for BC production with 1.81 g/l dry BC production.
Different organic and inorganic nitrogen sources were tested to select the best nitrogen source for BC production. The results indicated that, peptone was the best nitrogen source for bacterial cellulose production by Komagataeibacter hansenii (MH1) with 1.96 g/l dry BC. Also different peptone concentrations were tested but 1% peptone was the best concentration for BC production on modified GAM medium by komagataeibacter hansenii (MH1) with 2.62 g/l dry BC production.
Five concentrations of acetic acid were tested to select the optimum acetic acid concentration for BC production by Komagataeibacter hansenii (MH1). 4 ml/l acetic acid was found to be the best concentration on modified GAM medium with 3.45 g/l dry BC production.
The results of optimization of ethanol concentration showed that, 7ml/l ethanol was the best concentration for BC production by Komagataeibacter hansenii (MH1) on modified GAM medium with 3.69 g/l dry BC production.
Different initial pH values were tested and the results showed that, initial pH 3.46 was the best pH value for bacterial cellulose production on modified GAM medium by Komagataeibacter hansenii (MH1) with 3.68 g/l dry BC production. Also the strain Komagataeibacter hansenii (MH1) showed the ability to growth and cellulose production at 4-6 pH values but the amount of BC produced were lower than that produced at 3.46 pH value.
Different incubation temperatures were also tested to select the optimum temperature for BC production by Komagataeibacter hansenii (MH1) on modified GAM medium and the results indicated that the optimum temperature for BC production by an isolated strain was 30˚C with 3.69 g/l dry BC production.
The results of shaking and static incubation sowed that, isolated strain Komagataeibacter hansenii (MH1)was able to produce bacterial cellulose under shaking and static incubation but the amount that produced under shaking incubation (1.7 g/l dry BC) was lower than that produced under static incubation (3.66 g/l dry BC ).
During 18 days of incubation the results showed that, bacterial cellulose production by Komagataeibacter hansenii (MH1) on modified GAM medium was increased with time till it reaches its maximum value at 15 days with 5.86 g/l dry BC production and the amount of BC produced returned to decrease after 15 days.
The ability of isolated strain Komagataeibacter hansenii (MH1) to produce cellulose on low coast raw materials as a carbon source on modified GAM medium was tested and the results showed that, isolated strain Komagataeibacter hansenii (MH1) was able to use raw materials as a carbon source and produce bacterial cellulose on it but begasse showed the best one of the tested raw materials with 1.71 g/l dry BC production.
Also the ability of isolated strain Komagataeibacter hansenii (MH1) to produce cellulose on low coast raw materials as a carbon+ nitrogen source on modified GAM medium was tested and the results showed that, isolated strain Komagataeibacter hansenii (MH1) was able to use raw materials as a carbon source and produce bacterial cellulose on it but begasse showed the best one of the tested raw materials with 1.14 g/l dry BC production.
The results of ATR-FTIR spectroscopy analysis on dried pellicle produced by Komagataeibacter hansenii (MH1) was identified as cellulose.