Investigation of the possibility of culturing aerobic yeast with oxygen nanobubble addition and evaluation of the results of batch and semi-batch cultures of Saccharomyces cerevisiae

Authors:

• Paweł Sobieszuk,
• Alicja Strzyżewska,
• Karol Ulatowski

Abstract

Nanobubble dispersions have been intensively studied in recent years. Their expanding applications include a wide range of industrial and biochemical processes. Nanobubble-saturated water intensifies the growth of bacteria, animal cell lines, plants, and animals. However, their influence on yeast growth has not been investigated. Yeast is an important microorganism in the biotechnology and food industries. Intensified growth of yeasts would be beneficial for basic and industrial purposes. In this study, the possibility of culturing Saccharomyces cerevisiae with oxygen nanobubbles as the sole source of oxygen was investigated. Batch, sequential batch, and semi-batch cultures were grown with the addition of oxygen nanobubbles, along with classical aeration of the bioreactor. The results were compared to batch cultures without nanobubble addition. Biomass, substrate, and oxygen profiles were determined throughout the time of culture. The Monod and Tsao–Hanson models were used to describe yeast growth. The balance of the bioreactor culture was determined using MATLAB software. The comparison of balance and kinetic parameters demonstrated a higher maximum specific growth rate of yeast in nanobubble cultures than in cultures without nanobubble addition.