Complex coacervates and nanoemulsions using functionalized polymers as advanced strategies for the delivery of bioactive compounds to control phytopathogens in agriculture.

• Grant number: 25/03567-9
• Support Opportunities: Scholarships abroad - Research Internship - Post-doctor
• Start date: June 01, 2025
• End date: May 31, 2026
• Field of knowledge: Agronomical Sciences - Agronomy - Plant Health
• Principal Investigator: Michel Brienzo
• Grantee: Jaiber Humberto Rodriguez Llanos
• Supervisor: Andrij Pich
• Host Institution: Instituto de Pesquisa em Bioenergia (IPBEN). Universidade Estadual Paulista (UNESP). Campus de Rio Claro. Rio Claro , SP, Brazil
• Institution abroad: RWTH Aachen University, Germany
• Associated to the scholarship: 23/06702-9 - Development of a Chitosan Biogel for Carrying Eugenol in Combating Citrus Canker: Scale Production and Field Evaluation, BP.PD

Abstract

Citrus farming in Brazil is a highly relevant economic activity, positioning Brazil as the world's largest exporter of sweet orange juice. However, the sector faces significant challenges, especially with citrus canker, a disease that compromises crops by causing the leaves and fruits to fall. Copper has been used intensively to control the disease, leading to the accumulation of heavy metals in the soil and generating adverse environmental and health impacts. In this study, it is proposed an innovative and sustainable approach to mitigate the effects of this disease using natural essential oils such as eugenol and thymol, which are known for their antimicrobial action. However, to enable their use and persistence in plants, this project aims to develop a controlled release system through the chemical and enzymatic modification of chitosan and cassava starch, promoting the inclusion of hydrophobic groups and soft crosslinks that enhance the affinity and encapsulation of the oils by high-energy techniques. Subsequently, the nanoemulsions are integrated through microfluidization, promoting a complex coacervation process that results in a multilayer structure, where the electrostatic and hydrophobic interactions between the polymers ensure sequential and controlled release of the bioactive compounds. Thus, this project not only seeks to mitigate the impacts of citrus canker but also contributes to the strengthening of Brazilian citrus farming, promoting more versatile, innovative, and environmentally responsible agricultural practices.