Monitoring the Antibacterial Effect of Rosin Acids in an Austrian Beet Sugar Plant by Amplicon-Based Sequencing and Flow Cytometry

• Main Authors: Cordula K. Moser, Christina Ukowitz, Ulrike Zitz, Florian Emerstorfer, Walter Hein, Wolfgang Kneifel, Konrad J. Domig
• Format: Article
• Language: English
• Published: MDPI AG 2021-01-01
• Series: Applied Sciences
• Subjects: beet sugar factory; bacterial communities; antimicrobial; rosin acids; flow cytometer
• Online Access: https://www.mdpi.com/2076-3417/11/2/737

For decades, microorganisms in beet sugar production have been studied using culture-based methods. However, these methods are not sufficient to describe such a complex bacterial community. In this study, therefore, an amplicon-based sequencing technique (Illumina MiSeq platform) was applied to characterize the bacterial community and its dynamics in the extraction area and juice purification station of an Austrian beet sugar plant. Depending on the process conditions thermophilic bacteria, such as <i>Geobacillus</i> spp., <i>Caenibacillus</i> spp., and <i>Thermus</i> spp., and mesophilic bacteria, such as <i>Leuconostoc</i> spp. and <i>Bacillus</i> spp., were found. Besides these microbiological characteristics, the antimicrobial effect of a rosin acid-based product (Defostab 220) on the bacterial communities was investigated in industrial and laboratory trials. The antimicrobial effect of a given concentration of rosin acid varies from bacteriostatic to bactericidal effects on different occurring groups of bacteria.