Propriedades de celulose bacteriana: influência do tempo de fermentação em diferentes cepas de Komagataeibacter

Abstract

Bacterial cellulose (BC) is a biopolymer synthesized by several bacteria, which has properties superior to plant cellulose, such as high crystallinity, porosity, thermal and mechanical resistance. Due to its characteristics, BC has several applications, such as dressings, construction of artificial blood vessels, etc ... that demand specific properties, which can be obtained through functionalization or through the manipulation of the fermentation process. This study aimed to determine the effect of fermentation time and the strain of microorganisms on the properties of BC. The cultivation was static with the strains K. xylinus ATCC 53582 and K. hansenii ATCC 23769, synthetic culture medium HS and 4, 6, 8 and 10 days of fermentation. The obtained BCs were purified and characterized by infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), x-ray diffraction (XRD), stress tests, water absorption capacity, thermoporometry (TP-DSC), electron microscopy (SEM), degree of polymerization (DP), productivity and production were measured for each fermentation. The results of FTIR, porosity, mechanical resistance and water absorption were submitted to a multivariate statistical analysis. The fermentation time had a direct influence on the properties of the CBs produced, regardless of the bacteria used. Except for chemical composition and thermal stability, the strain of microorganisms also influenced the properties of the obtained CBs.