Bacterial cellulose production by Gluconacetobacter hansenii in an agitated culture without living non-cellulose producing cells

Abstract

Bacterial cellulose (BC) was produced by Gluconacetobacter hansenii PJK in ajar fermenter equipped with a 6 flat-blade turbine impeller and the relationship between the populations of non-cellulose producing cells (Cel(-) mutants) and BC production was investigated. The population of Cel(-) mutants converted from cellulose producing cells (Cel(+) cells) decreased as the impeller speed increased. Cel(+) cells seemed to be protected from the strong shear stress generated by the impeller rotating at a high speed by the BC net produced by the cells. There was an optimum impeller speed in maximizing the population of Cel(+) cells and BC production. The optimum impeller speed increased with ethanol supplementation to a basal medium. The by-product, water-soluble polysaccharide (WSPS), was a hornopolysaccharide of glucuronic acid. WSPS production was related to the population ratio of Cel(+) cells to the total cells. (c) 2005 Elsevier Inc. All rights reserved.