Evaluation of antibacterial activity and synergistic effect of emulsions formed by rhamnolipids and essential oils against Xanthomonas citri subsp. citri.

• Grant number: 23/13083-3
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): May 01, 2024
• Effective date (End): July 31, 2025
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Daiane Cristina Sass
• Grantee: Maria Olimpia Pereira Sereia
• Host Institution: Instituto de Biociências (IB). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil

Abstract

The bacterium Xanthomonas Citri subsp. Citri known to cause citrus cancer in a wide variety of citrus of commercial importance is classified as a quarantine pest in Brazil. The control of this bacterium is usually performed by the use of synthetic chemical compounds (mostly copper-based), among other practices, which cause negative impacts on health and the environment, making the search for sustainable alternatives to combat these bacteria increasingly important. A possible alternative to synthetic chemicals that has aroused great interest is the use of essential oils, in general, the active components of essential oils show low toxicity to mammals and a reduced persistence in the environment. These characteristics, associated with antifungal and antibacterial activities, place essential oils as viable candidates to be explored in the development of natural agricultural pesticides. Rhamnolipids are biosurfactants glycolipids produced mainly by Pseudomonas aeruginosa, these compounds have been reported as potential metabolites for the control of phytopathogenic bacteria, in addition, they have physical propertieschemicals that promote the formation of emulsions, which allows these biosurfactants to be mixed with other compounds, such as essential oils, promoting the formation of emulsions, that besides presenting a better applicability in the industry can increase antimicrobial activity (synergistic effect) and stability. In this sense, this project aims to evaluate the antibacterial action in vitro, plant and fruit, as well as the synergistic effect of emulsions formed by rhamnolipids and essential oils against Xanthomonas Citri, which causes citrus cancer in Citrus.