Study of the Molecular Weight of Pullulan Produced by Aureobasidium pullulans from Industrial Waste

The objective of this research was the sustainable development of pullulan and its structural and rheological characterization. In addition, the cultivation of the A. pullulans Y2092 strain by submerged fermentation on a laboratory scale was evaluated, valuing the use of industrial waste (residual brewery's yeast), RBY, and a low-cost renewable raw material VHP (very high polarization sugar). A 22 factorial statistical design of experiments was used to analyze the molecular weight of the pullulans produced. The maximum value of 1955 kDa was determined for the pullulan recovered after 96 h of fermentation in the mineral medium added with 70 g/L of VHP and 50 g/L of RBY. The FTIR analysis for the pullulan obtained was similar to the commercial pullulan. The rheological behavior of pullulan solutions is shown, evidencing the relationship between this property and Mw. The results from all analyses indicate that the pullulan obtained is suitable for the future production of biopolymeric films.

Automated summary

The goal of this study was to investigate the sustainable development and characterization of pullulan, including its structure and rheological properties. The cultivation of A. pullulans strain and the utilization of industrial waste and low-cost renewable raw material were evaluated. The results showed that the pullulan obtained under specific fermentation conditions is suitable for the production of biopolymeric films in the future.