Schinus areira Essential Oil: from antibacterial characterization to the development of nanoformulations.

ANDREA C. CUTRÓ; ANIKE P.V., FERRERYRA MILLAR; BORDÓN, ANAHÍ; MARIA SUMAMPA, CORIA; RODRIGUEZ, SERGIO A.; HOLLMANN, AXEL

Rosario

Congreso; LIX Reunion Annual de la Sociedad argentina de Invetsigaciones en Bioquímica y Biología Molecular (SAIB 2023).; 2023

Sociedad de Bioquimica y Biología Molecular SAIB

Essential oil (EO) obtained from Schinus areira leaves has been shown to have antibacterial activity against S. aureus in our previous research. This activity was accompanied by significant changes in the electrical potential of the cell surface and bacterial membrane model. The main goal of the present research is to get a deeper understanding of the mechanisms underlying the antibacterial effects previously observed. In this sense, through fluorescence microscopy, the integrity of S. aureus cells was evaluated as a function of EO concentration and incubation time. It could be noticed a significant increase in cell permeability, which showed dose and time dependance. Additionally, by fluorescence spectroscopy and dynamic light scattering studies using DMPC:DMPG (5:1) liposomes, it was possible to evaluate the alterations that EO induces in the lipid membranes. According to these studies, the EO caused changes in the lipid membrane packing, improving fluidity, reducing cohesive interactions between phospholipids, and making it easier for water to access the interior of the lipid bilayer. All these alterations result in an increase on the permeability of the liposomes in good agreement with S. aureus experiments. Afterwards, potential intracellular targets for the EO, as genomic DNA and oxidative metabolism were investigated. These experiments showed that S. areira EO partially degraded DNA and brought on oxidative stress. Finally, in order to achieve practical applications such as hydrosoluble nanoformulations, green silver nanoparticles were synthesized by using the EO as a biocomposite for reduction and stabilization. The nanoparticles obtained showed antimicrobial activity. All these findings highlight the multifaceted antibacterial action of this EO and its potential applications as an antimicrobial obtained from a locally significant natural resource.Key words: Schinus areira, antibacterial, mechanisms, nanoformulations.