Effect of Glucose Concentrations on the Growth and Metabolism of <i>Brettanomyces bruxellensis</i> under Aerobic Conditions

Abstract

Acetic acid can be directly produced from glucose in one-step fermentation by using yeasts of the genus Brettanomyces bruxellensis, hence increasing the industrial application to manufacture products with simplified bioprocesses. Thereby, this work evaluates the influence of initial glucose concentration on the growth and acetic acid production by B. bruxellensis. The results obtained confirmed the presence of Crabtree effect on B. bruxellensis under low glucose concentrations. The maximum acetic acid concentration reached was 15.4 g•L −1 starting with 100 g•L −1 leading to a product yield of 0.154 g•g −1 and a specific acetic acid production rate of 0.05 g•g −1 •h −1. The results also indicate that after reaching the acetic acid critic threshold of 4 g•L −1 the metabolism can induce the growth second phase even residual glucose was present on the culture media at high starting glucose concentrations. Additionally, it was observed a lineal relationship between cell viability and acetic acid production.