@article{28f7bbc97e05448f84b75df24cdaae92,
title = "Hexyl Gallate Loaded Microgels Enable Efficient Protection Against Citrus Canker",
abstract = "The development of efficient and environmentally friendly plant protection systems is one of the major challenges for a sustainable agriculture of the future. Citrus canker caused by the pathogen Xanthomonas citri subsp. citri (X. citri) affects all cultivated citrus species worldwide and is responsible for enormous economic losses and restrictions in international trade. Currently used commercial copper-based formulations are the origin of contamination for soil and groundwater, affecting local ecosystems and human health. A copper-free sustainable microgel-based plant protection system able to efficiently combat X. citri is developed. Microgels decorated with anchor peptides exhibit strong non-covalent attachment to the surface of orange leaves and have the ability to release hexyl gallate, which inhibits the growth and spreading of pathogens. The tailored design of the microgel network allows high loadings of hexyl gallate (up to 40 wt.%) and a controlled release of gallates from microgels that provide long-term protection. The antibacterial activity of the hexyl gallate-loaded microgels is demonstrated by various in vitro assays as well as on orange plants in greenhouse settings. The experimental results suggest that the developed sustainable microgel-based plant protection system for citrus trees allows efficient abatement of X. citri and reduces environmental pollution caused by copper formulations.",
keywords = "alkyl gallates, anchor peptides, citrus canker, drug delivery, microgels, plant protection, tannic acid",
author = "Susanne Braun and Guilherme Dilarri and {de Lencastre Novaes}, {Leticia C.} and Philipp Huth and Alexander T{\"o}pel and Larissa Hussmann and Alexander Boes and {da Rocha}, {Miguel Divino} and Felix Jakob and Regasini, {Luis Octavio} and Ulrich Schwaneberg and Henrique Ferreira and Andrij Pich",
note = "Funding Information: S.B., G.D., and L.C.d.L.N. contributed equally to this work. S.B. would like to express her gratitude toward Yannick J. Nu{\ss}baum and Sven Pudleiner for their help as research students as well as Jan Grotel{\"u}schen for his assistance as a student helper and Jan Luca Clemens and Jan Niklas Zinn for their support as trainees. The authors wish to thank Silke Boinski and Stefan Hauk for the microscopy measurements of our microgel samples. The authors acknowledge the measurements of Raman spectroscopy and thank Bea Becker. Further the authors appreciate the extraction of wax from orange tree leaves by Christin Wittmann as well as the help and advice of Kevin Broi with the setup to investigate UV stability of G6. G.D. received a Ph.D. scholarship from Funda{\c c}{\~a}o de amparo {\`a} pesquisa do estado de S{\~a}o Paulo (FAPESP 2017/07306-9 and FAPESP 2018/23306-1). A.P. thanks the Deutsche Forschungsgemeinschaft (DFG) for financial support within the Collaborative Research Center SFB 985 (grant no. 191948804). Parts of the analytical investigations were performed at the Center for Chemical Polymer Technology CPT, which was supported by the European Commission and the federal state of North Rhine-Westphalia (grant no. 300088302). Financial support is acknowledged from BMBF (grant no. 031B0384), FAPESP (grant no. 2015/50162-2), INCT Citros (FAPESP: grant no. 2014/50880-0 and CNPq: grant no. 465 440/2014-2), NWO (grant no. 21.401) and Leibniz Competition - Leibniz Transfer (grant no. T130/2022). Publisher Copyright: {\textcopyright} 2023 The Authors. Advanced Functional Materials published by Wiley-VCH GmbH.",
year = "2024",
month = feb,
day = "19",
doi = "10.1002/adfm.202305646",
language = "English",
volume = "34",
journal = "Advanced Functional Materials",
issn = "1616-301X",
publisher = "Wiley-VCH Verlag",
number = "8",
}