Biossíntese de celulose bacteriana a partir do cultivo de cultura de kombucha em resíduo do processamento de mandioca

Abstract

Bacterial cellulose is a biopolymer obtained through the metabolic activity of microorganisms; this bioproduct has been widely used in pharmaceutical, cosmetic, food and even biomedical industries. Due to the high costs of purification and obtaining by means of culture traditionally used in the production of bacterial cellulose, alternative carbon sources, such as the use of by-products/residues of different raw materials, have been evaluated. Considering manipueira a residue from the cassava processing industry and its characteristics such as high concentrations of nitrogen, phosphorus, potassium and carbohydrates, the present work evaluated the biosynthesis of bacterial cellulose from the cultivation of kombucha culture in this residue. For this, analyzes of characterization of the liquid effluent and stabilization treatment with controlled temperature were used, in which a reduction of 75% of cyanide was observed when a stabilization time of 72 hours was used at a controlled temperature of 30±2 degrees Celsius . Regarding the Chemical Oxygen Demand (COD), it presented 1870mgO2 L-1 and the acute toxicity analysis with Vibrio fischeri showed a toxicity factor of 64, even after the stabilization procedure, which can be considered toxic. Thus, to evaluate this residue in obtaining cellulose by fermentation during kombucha cultivation, seven different proportions of manipueira and HS control medium (Hestrin Scharamm – traditionally used in cultivation) were evaluated for a period of 15 days. According to the results, a higher yield was obtained in the HS control medium (Hestrin Scharamm) (0.3057±0.0737 g .L-1 day-1), followed by the fraction of 80% HS and 20% manipueira (0.2749 ±0.0069 g L-1 day-1), resulting in only a 4,72% decrease in this value in relation to the control condition. In this way, as this work has an innovative character and because it is still about initial experiments, the potential of using this residue from cassava processing as promising in the biosynthesis of the biofilm in question is verified.