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Melaleuca alternifolia essential oil (MaEO) is a green antimicrobial agent suitable for confection eco-friendly disinfectants to substitute conventional chemical disinfectants commonly formulated with toxic substances that cause dangerous environmental impacts. In this contribution, MaEO-in-water Pickering emulsions were successfully stabilized with cellulose nanofibrils (CNFs) by a simple mixing procedure. MaEO and the emulsions presented antimicrobial activities against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Moreover, MaEO deactivated the SARS-CoV-2 virions immediately. FT-Raman and FTIR spectroscopies indicate that the CNF stabilizes the MaEO droplets in water by the dipole-induced-dipole interactions and hydrogen bonds. The factorial design of experiments (DoE) indicates that CNF content and mixing time have significant effects on preventing the MaEO droplets' coalescence during 30-day shelf life. The bacteria inhibition zone assays show that the most stable emulsions showed antimicrobial activity comparable to commercial disinfectant agents such as hypochlorite. The MaEO/water stabilized-CNF emulsion is a promissory natural disinfectant with antibacterial activity against these bacteria strains, including the capability to damage the spike proteins at the SARS-CoV-2 particle surface after 15 min of direct contact when the MaEO concentration is 30 % v/v., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier B.V.)

Chitosan is a cationic polysaccharide with intrinsic antimicrobial properties that can be used as an ecological alternative to develop functional materials to inhibit the proliferation of microorganisms. This work evaluates chitosan nanocapsules (CNs) as a self-disinfecting agent to provide bactericidal activity on cotton fabrics (CF), using polyacrylate to bind the CNs on the CF surface. The fabrics were characterized by Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), contact angle (CA), moisture retention, and antimicrobial tests against Escherichia coli and Bacillus subtilis . The FTIR results showed new peaks related to chitosan structure, indicating the adequate fixation of the CNs on the cotton fibers. SEM images corroborated the polyacrylate binder's efficient adhesion, connecting the CNs and the cotton fiber surface. The CF surface properties were considerably modified, while CN/polyacrylate coating promoted antibacterial activity against the B. subtilis (gram-positive bacteria) for the developed wipe, but they do not display bactericidal effects against E. coli (gram-negative bacteria)., Supplementary Information: The online version contains supplementary material available at 10.1007/s11998-023-00761-y., (© American Coatings Association 2023, Springer Nature or its licensor (e.g. a society or other partner) holds exclusive rights to this article under a publishing agreement with the author(s) or other rightsholder(s); author self-archiving of the accepted manuscript version of this article is solely governed by the terms of such publishing agreement and applicable law.)