Preparation, Characterization, and In Vitro Testing of Nanoclay Antimicrobial Activities and Elicitor Capacity

DANILA MERINO; YAMILA MANSILLA; CLAUDIA CASALONGUÉ; VERA A. ALVAREZ

Mar del Plata

Simposio; XVI Simposio Latinoamericano de Polímeros (SLAP 2018) y el XIV Congreso Iberoamericano de Polímeros (CIP 2018); 2018

Currently, the agriculture is going through a period of significant challenges marked by climate change, urbanization and environmental issues such as, the accumulation of pesticides and fertilizers. In parallel, the great growth of the world population that is expected to exceed the 9 billion by 2050 makes evident the need to carry out new innovative developments committed to the care of the environment and sustainable solutions. Clay based nanocomposites (nanoclays) are interesting systems to hold a wide type of active substances with a wide field of industrial applications. In this work, Bentonite-chitosan nanoclay was obtained via cationic exchange of natural bentonite (Bent) with an aqueous solution of chitosan (CS). CS is a linear chain cationic polymer derived from chitin, the second most abundant polymer in nature. It has been shown that chitosan causes cell death in a large variety of pathogenic fungi and inhibits the growth of pathogenic bacteria. It has been well demonstrated that CS induces numerous biological responses in plants and improves defense responses to biotic and abiotic stresses.Bent-CS nanoclay physicochemical and morphological properties were discussed under the light of Fourier Transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), transmission (TEM) and scanning electron microscopy (SEM)1. The antimicrobial action of Bent-CS nano-clay was assayed onto phytopathogens, the bacterium model Pseudomonas syringe p.v. tomato DC3000 (Psy) and the necrotrophic fungus Fusarium solani f. sp. eumartii (F. eumartii). In addition, the induction of defence mechanisms was assayed onto tomato plantlets.