Evaluation of the Method of Periodic Medium Renewal of Bacillus aryabhattai RAF 5 and Analysis of P(3HB) Production

The purpose of this study was to assess the ability of <i>Bacillus aryabhattai</i> RAF 5 to produce P(3HB) under conditions of periodic medium renewal (PMR). The producer was isolated and confirmed using transmission electron microscopy (TEM), which revealed the presence of more than 10 dense P(3HB) granules per cell. The purity of the isolated polymer was evaluated using Fourier transform infrared spectroscopy (FTIR). The maximum concentration of P(3HB) reached 18.70 g/L with biomass accumulation of 21.44 g/L after 120 h of incubation under PMR conditions, which is 6.61 g/L higher than the concentration of P(3HB) obtained with the standard cultivation method. The resulting polymer was later used to create a membrane, which was then tested for permeability to water vapor, oxygen, carbon dioxide, and a biofilm puncture test. The resulting P(3HB)-based membranes have promising barrier properties, indicating their suitability for various industrial applications, including biomedical devices.