OVERVIEW: USE OF ANTIMICROBIALS IN FERMENTATION PROCESSES IN THE FUEL-ETHANOL INDUSTRY IN BRAZIL
Authors: Patrícia Regina Kitaka, Cláudia Steckelberg and Valéria Maia Merzel
Patrícia Regina Kitaka: Bioprocess Division, CPQBA, University of Campinas, Campinas/São Paulo State/Brazil. Zipcode: 13.141-026
Cláudia Steckelberg: Bioprocess Division, CPQBA, University of Campinas, Brazil.
Valéria Maia Merzel: Microbial Resources Division, CPQBA, University of Campinas, Brazil.
ABSTRACT
Bacterial contamination in fermentation processes for bioethanol production is one of the most important problems, resulting in significant fermentation losses in this industry. The main strategy to overcome this challenge in the industry is the use of a variety of antimicrobials, including antibiotics for human and animal use. This indiscriminate practice may intensify antimicrobial resistance (AMR) and result in multidrug-resistant (MDR) microorganisms. This study aimed to outline a current overview of antimicrobial use in sugarcane fuel ethanol fermentation in Brazil, addressing some industrial aspects and the environmental and human health consequences. Interviews with 10 Brazilian industrial units (2019/2020 harvest) revealed that all units monitor and control contamination, with the use of antibiotics being the most prevalent and frequent strategy. The most common antibiotics include monensin sodium, virginiamycin, penicillin, quinolones, and aminoglycosides. The frequency of use varies, with 50% of units using antibiotics continuously. Ninety percent of the units had never used alternative strategies to traditional antibiotics, and the only one that did reported low effectiveness. Therefore, considering what is already known: the continuous and unrestricted use of antibiotics increases the selective pressure for resistant or multidrug-resistant microorganisms, with worrying implications for human health (transfer of resistance genes) and the environment. Overall, these findings present a worrying scenario about contamination control in the bioethanol industry and emphasize the ecological and socioeconomic importance of further research into alternatives to antibiotics in bioethanol production processes, highlighting the imminent need for new technological solutions.
Keywords: Antimicrobial use, Fuel ethanol fermentation, Bacterial contamination, Antibiotic resistance, Bioethanol industry, Multidrug-resistant bacteria