Process for the production of microbial cellulose

Claim 1

A process for the production of extra-cellular microbial cellulose in which a bacterial strain capable of producing extra-cellular microbial cellulose is aerobically cultivated in a culture medium containing a carbon source wherein the process comprises the steps: (a) a growth step in which the bacterial strain is cultivated at a temperature within the range 15° C. to 35° C. and an initial pH within the range 4 to 6.5 in stirred batch culture until substantially all the carbon source present has been utilized and the culture is carbon limited; (b) an accumulation step carried out at a temperature within the range 15° C. to 35° C. and an initial pH within the range 4 to 6.5 in which the carbon source is supplied continuously to the carbon limited culture at a rate sufficient to maintain it in the supernatant at a level not greater than 0.5 g/l and to maintain the culture in carbon limitation thereby enabling microbial cellulose to accumulate during stirred cultivation; (c) a removal step in which bacterial cells and accumulated microbial cellulose are removed from the culture at the end of the accumulation step; and (d) a separation step in which microbial cellulose is separated from the cells.