Bacterial cellulose has many unique properties that include its prepn. in high purity, absorption of large amts. of water, and a microfibril structure. The ability of cellulose producing bacteria to in vivo incorporate non-natural sugar units in the polymer was studied. Culturing Gluconacetobacter hansenii on glucose and corn-steep liquor (CSL) gave microbial cellulose. However, when the organism was grown on different ratios of glucose and N-acetyl glucoseamine (NAG), microfibrous polymers were obtained that had both glucose and NAG repeat units in different proportions. Studies of sugar utilization and polymer formation as a function of culture time were performed. Sequential enzymic degrdn. of the polymers using cellulases, cellobiase and chitinase liberated sugars that were analyzed by HPLC. By this method NAG contents in the copolymer up to 35 mol-% were found. Studies of the NAG/glucose copolymers by X-ray spectroscopy showed new X-ray bands and decreases in crystallinity relative to microbial cellulose.
Engineering of aminated microbial cellulose / Shah V.; Durrani-Tariq S.; Felse A.P.; Gao W.; Focarete M.L.; Scandola M.; Gross R.A.. - ELETTRONICO. - (2004), p. CARB-084. (Intervento presentato al convegno 228th ACS National Meeting tenutosi a Philadelphia, PA, United States nel August 22-26, 2004).
Engineering of aminated microbial cellulose
FOCARETE, MARIA LETIZIA;SCANDOLA, MARIASTELLA;
2004
Abstract
Bacterial cellulose has many unique properties that include its prepn. in high purity, absorption of large amts. of water, and a microfibril structure. The ability of cellulose producing bacteria to in vivo incorporate non-natural sugar units in the polymer was studied. Culturing Gluconacetobacter hansenii on glucose and corn-steep liquor (CSL) gave microbial cellulose. However, when the organism was grown on different ratios of glucose and N-acetyl glucoseamine (NAG), microfibrous polymers were obtained that had both glucose and NAG repeat units in different proportions. Studies of sugar utilization and polymer formation as a function of culture time were performed. Sequential enzymic degrdn. of the polymers using cellulases, cellobiase and chitinase liberated sugars that were analyzed by HPLC. By this method NAG contents in the copolymer up to 35 mol-% were found. Studies of the NAG/glucose copolymers by X-ray spectroscopy showed new X-ray bands and decreases in crystallinity relative to microbial cellulose.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
