Optimization and characterization of bacterial cellulose produced by Komagatacibacter xylinus PTCC 1734 using vinasse as a cheap cultivation medium

Abstract

In the present study, vinasse was used to produce bacterial cellulose (BC) by Komagatacibacter xylinus PTCC 1734. Central composite design (CCD) was utilized to evaluate the effects of vinasse concentration (%) and incubation time (Day) on different responses such as thickness as well as wet and dry weights of the produced BC membrane. The increase of vinasse concentration and incubation time caused an increase in the wet weight of BC; however, thickness decreased by increasing incubation time. The BC produced at the optimized conditions (40% vinasse and 10 days) was characterized and compared with the BC produced in Hestrin-Schramm medium as a control medium. Scanning electron microscopy (SEM) confirmed 3D network structure of BC. The average diameter of fibrils was in the range of 30–120 nm. In addition, the Fourier transform infrared spectroscopy (FT-IR) showed completely similar spectrum for both optimal and control samples. The X-ray diffraction (XRD) analysis approved the crystalline structure of the produced BC. Furthermore, the thermogravimetric analysis (TGA) test revealed no difference in the thermal stability of the optimum and control sample. According to the results, the vinasse, as a by-product, could be used as a cheap and suitable carbon source for the production of BC.