Caracterização de celulose bacteriana

Abstract

Bacterial cellulose obtained from kombucha fermentation presents itself as a biomaterial with high potential, whose relevance is justified by its purity, crystallinity, and superior structural properties compared to plant cellulose, enabling applications in biomedicine, food, and materials engineering. The general objective of this work was to produce and characterize bacterial cellulose membranes, encompassing their production, purification, and morphological and functional evaluation. The methodology involved the aerobic fermentation of sweetened black tea using a commercial SCOBY, followed by membrane purification with an alkaline solution, oven drying, and subsequent characterization by scanning electron microscopy, texture analysis, rehydration capacity, and solubility. The results indicated that thermal drying caused structural deformations and reduced mechanical integrity, evidenced by micrographs and the smaller rupture distance of the dehydrated membranes compared to the wet ones. The rehydration capacity remained stable at around 64%, lower than values found in studies with lyophilization, suggesting that high-temperature drying caused partial collapse of the porous structure. Solubility remained low and practically constant at all temperatures evaluated, confirming the insoluble nature of cellulose. It is concluded that the process used was efficient for obtaining the material, allowing the characterization of its properties and the identification of limitations associated with the drying method. It is recommended to explore alternative dehydration techniques and improved cultivation conditions, in order to preserve the nanofibrillar structure and enhance future technological applications.