B.S. HUNGUND AND S.G. GUPTA
Abstract
Some Gluconacetobacter strains produce cellulose called bacterial cellulose (BC). BC is expected to be a commodity material in various fields of industry. Cellulose production by Gluconacetobacter xylinus NCIM 2526 was affected by the type and concentration of carbon source, nitrogen source, pH and temperature. Among the carbon sources fructose, mannitol and inositol were found to be suitable for optimum levels of cellulose production. Cellulose yield was maximum at 4% (w/v) of inositol (6.0 g/l). The organism was able to utilize a wide range of nitrogen sources such as peptone, casein hydrolyzate, beef extract, and malt extract for cellulose production. Also the effect of pH, temperature and supplementary effect of metal ions & solvents on BC production had been evaluated. pH of 6.5 and 30oC temperature were found to be suitable for cellulose production. Addition of metal ions like zinc, magnesium, calcium, and nickel at a level of 100 ppm and solvents like methanol and ethanol were found to be stimulatory for cellulose production. Using G. xylinus NCIM 2526 in the modified medium, the amount of cellulose produced was almost double (6.6 g/l) as compared to that in standard medium.