Exploring the impact of antimicrobials on synthetic microbial communities relevant to bioethanol production from sugarcane

• Grant number: 25/02887-0
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2025
• End date: July 31, 2029
• Field of knowledge: Engineering - Chemical Engineering - Chemical Process Industries
• Principal Investigator: Andreas Karoly Gombert
• Grantee: Carolina Teixeira Martins
• Host Institution: Faculdade de Engenharia de Alimentos (FEA). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Brazil is the second-largest producer of bioethanol in the world, with sugarcane biorefineries playing a crucial role in driving economic growth and sustainability. Despite their efficiency, these biorefineries face significant challenges, particularly microbial contamination by lactic acid bacteria (LAB), which reduces ethanol yields, increases production costs, and raises environmental concerns due to the extensive use of sulfuric acid, antibiotics, and other antimicrobial compounds. The present PhD research aims to investigate the microbial dynamics in the fermentation processes of Brazilian biorefineries. We will use collected samples from three biorefineries over two harvest seasons. Samples will be analyzed using culturomics to isolate microorganisms, followed by high-throughput screening of these isolates to assess their metabolic profiles, evaluate biofilm formation, and determine antibiotic susceptibility. We will also design synthetic microbiome combinations to further investigate the influence of each species and antimicrobial compounds on the microbial population. Additionally, experiments in mini-biorefinery systems will simulate industrial conditions to test the resilience of microbial communities and the effect of antibiotics on their structure and function. Finally, bioinformatics analysis will be conducted from metagenomic and metatranscriptomic data to evaluate taxonomic composition, functional profiles, and microbial interactions. We expect that this comprehensive approach will provide critical insights into the microbial ecology of Brazilian alcoholic fermentations, reduce dependence on traditional antimicrobials, and optimize fermentation efficiency, ultimately contributing to a more sustainable bioethanol industry in Brazil. (AU)