Continental-scale insights into the sugarbeet diffusion juice microbiomes

Area of Science:

• Microbiology
• Food Science
• Biotechnology

Background:

• Raw diffusion juice from sugar beets is susceptible to bacterial contamination, complicating sugar extraction.
• Microbial activity in juice can lead to significant sugar loss during processing.

Purpose of the Study:

• To profile bacterial communities in raw diffusion juice from North American sugar factories.
• To investigate the relationship between bacterial abundance, carbohydrate concentrations, and processing campaigns.
• To understand the role of specific bacteria, like Leuconostoc, in sugar degradation.

Main Methods:

• Full-length 16S rRNA amplicon sequencing for bacterial community profiling.
• Quantification of carbohydrate concentrations in juice samples.
• In vitro growth assays of Leuconostoc mesenteroides.

Main Results:

• Firmicutes was the dominant phylum (85.5%), with lactic acid bacteria (Leuconostoc, Lactobacillus) as core genera.
• A significant decrease in differentially abundant bacterial genera was observed between the 2021 and 2022 processing campaigns.
• Raffinose concentration positively correlated with Leuconostoc abundance, which rapidly consumed both sucrose and raffinose in vitro.

Conclusions:

• Bacterial communities in raw diffusion juice are dominated by Firmicutes, particularly lactic acid bacteria.
• Leuconostoc plays a key role in carbohydrate consumption, potentially causing sugar loss.
• Findings provide baseline data for developing strategies to mitigate microbial contamination in sugar processing.