Optimization and characterization of bacterial nanocellulose produced by Komagataeibacter rhaeticus K3
Paulina Jacek, Francisco A.G. Soares Silva, Fernando Dourado, Stanisław Bielecki, Miguel Gama
Abstract
In this work, a novel Bacterial NanoCellulose (BNC) producing strain, from Kombucha tea , was isolated and characterized. Based on 16S rRNA analysis the strain was identified as Komagataeibacter rhaeticus . Under static culture, K. rhaeticus K3 produces membranes with a relaxed structure, as observed by Scanning Electron Microscopy (SEM). The addition of 2% (v/v) ethanol to the culture media enhanced by more than 3-fold of the BNC yield. Response surface methodology (RSM) was performed with K. rhaeticus K3 , using a new low cost Eucalyptus Biomass Hydrolysate (EBH). The maximum experimental BNC yield was of 5.46 g/L, obtained with the following composition: 31.4 g/L of EBH; 2.89% (v/v) of ethanol and 10.8 g/L of Yeast extract/peptone. Texture Profile Analysis (TPA) of BNC membranes obtained using Hestrin-Schramm culture (HS) medium and optimized medium from EBH showed that membranes from EBH had higher resistance to compression, higher cohesiveness and resilience.