Title
Effect of semi-continuous operation mode parameters on bacterial cellulose and biomass production
Authors
TUGÇE BAYRAKDAR DENIZ DILAN DEMIRBAG ÖZLEM AYTEKIN and ALI ÖZHAN AYTEKIN

Received April 27, 2016
Published Volume 51 Issue 7-8 July-August
Keywords bacterial cellulose (BC), semi-continuous process, volume changing ratio, incubation time period, glucose concentration, surface area/volume ratio

Abstract
Bacterial cellulose (BC) has advanced properties, such as high crystallinity, high molecular weight and high purity. Therefore, it can be used extensively in the cosmetic and pharmaceutical industries. Because of the importance of BC, an economical production process is needed. In this study, BC production in a static culture was investigated with varied semi-continuous process parameters, including the volume changing ratio (%; ml/ml), the initial glucose concentration (%; g/100 ml) and the surface area/volume ratio (cm-1). BC and cell dry weight (CDW) were measured, and BC was characterized by tensile strength, SEM and FT-IR. BC productivity reached 0.36 g/L/day after 6 days of incubation. Semi-continuous process parameters were investigated by changing the medium every 6 days. The optimal parameter values for BC production were a volume changing ratio of 60%, an initial glucose concentration of 30% and a surface area/volume ratio of 0.85 cm-1. BC production reached 15.6 g/L in this semi-continuous process, which was 7.5-fold greater than in the batch process. This semi-continuous process is a good candidate for industrial-scale BC production.