Monitoring initial glucose concentration for optimum ph control during fermentation of microbial cellulose in rotary discs reactor

The study aimed to investigate the effect of initial glucose concentration on the microbial cellulose production using Acetobacter xylinum in a Rotary Discs Reactor (RDR- 2 liter volume). The fermentations were carried out for four days at temperature 28°C, initial pH 6.5, and 9 rpm of rotation speed; meanwhile, the initial glucose concentration was manipulated in the range of 0.5-5.0 % (w/v). The cell growth was stimulated using 1.4% (v/v) ethanol in the fermentation medium. The result indicated that 1% (w/v) of initial glucose concentration provided the highest microbial cellulose yield with total wet weight of 296.1657g/l. The increase of initial glucose concentration resulted to the decrease of microbial cellulose yield and greater pH drop after fermentation. It can be conclude that production of microbial cellulose using RDR could produce relatively much higher microbial cellulose with less amounts of glucose in a shorter fermentation period compared to static fermentation due to more efficient oxygen uptake during rotary movements and homogenous environment for microbial growth. Copyright © 2014 Trans Tech Publications Ltd, Switzerland.