Development of technology for biosynthesis new polysaccharide by the bacteria

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Several sugars were elucidated for the carbon source of Acetobacter xylinum. Three carbon sugars such as glycerol and glyceraldehyde were mainly examined. Improvement of yield and long tena cultivation were aacomplished by the use of glycerol as a carbon source instead of glucuse in the SH medium. Carbon thirteen NMR examination of the obtained polysacaharide was carried out to clarify the biosynthesis path way of the metabolism using carbon thirteen labeled glycerol as a carbon source. As a result, it was found that glycerol derivatives was digested and recunstnictedto glucese molecule again.In addition, medium cumposition was changed from the cunventional SH medium cuntaining glucase. It was found that amino hydrolysate was effective instead for bactopeptone and yeste extract, which lead the elimination of production cast of bacterial cellulose. Ammonium nitrate and sodium nitrate were added in the medium as a nitrogen source of the medium. In the former experiment, ammonium salt suc … More h as ammonium chloride was effective for the introduction of N-acetylglucosamine in the cellulose backbone. The use of nitrate was also effective for the introduction of N-acetylglucusamineinthe cellulose backbone. However enzyme digestive and molecular weight measurements revealed that the structure of the nitrate induced polysacaharide was different from that induced from ammonium salts. It was found that N-acetylglucusamine residue existed in the side chain of the cellulose backbone not in the cellulose backbone.In order to improve the yield of the bacterial cellulose, shallow pan cultivator was newly designedfor the biosynthesis of bacterial cellulose. This is a completely new ideabased on the fact thatAcetobacter xylinum is an arcobic bacteria Using this tethnology, bacterial cellulose is fabricated in several shapes, such as fiber, thin film. The film can be fabricated into elongated one and non-elongated one. Since bio synthesized bacterial cellulose thin film was removed slowly bacterial cellulose was continuously formed in the newly formed surface of the medium. Therefore, medium was effectively used for the bio synthesis of bacterial cellulose. Less