Development and antimicrobial activity of new biomaterial of Hevea brasiliensis latex and zinc oxide nanoparticles

• Grant number: 23/14723-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: February 01, 2024
• End date: January 31, 2025
• Field of knowledge: Biological Sciences - Biophysics - Biophysics of Processes and Systems
• Principal Investigator: Angela Mitie Otta Kinoshita
• Grantee: Joaquim Ferreira Brito
• Host Institution: Faculdade de Medicina Dr Domingos Leonardo Ceravolo. Universidade do Oeste Paulista (UNOESTE). Campus de Presidente Prudente. Presidente Prudente , SP, Brazil

Abstract

The acronym ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and species of Enterobacter, such as Escherichia coli) brings together the 6 most prevalent and worrying bacteria responsible for the majority of healthcare-associated infections (HAIs). These have several mechanisms to evade the biocidal effects of available antibiotics and generate thousands of hospitalizations and very high hospital costs throughout the world annually. Some strains of these bacteria are listed by the World Health Organization (WHO) as a top priority for the development of new antibiotics. The strains Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii and Pseudomonas aeruginosa are present on the skin, according to studies carried out with stethoscopes. The introduction of metal oxide nanoparticles, especially zinc oxide (ZnO), emerges as a promising strategy to address these challenges. Its antibiotic properties and the ability to be applied in different structural forms expand its potential in the biomedical field. Natural latex from the rubber tree Hevea brasiliensis, known for its ability to release controlled substances, joins the scene as a promising matrix for biomaterials. Its proven ability in tissue regeneration contributes to the proposal to develop functional dressings that combine the angiogenic and re-epithelialization activity with the antimicrobial activity of ZnO nanoparticles. Therefore, this work aims to develop a new biomaterial composed of latex from the rubber tree Hevea brasiliensis, associated with zinc oxide nanoparticles and analyze the antimicrobial potential against Staphylococcus aureus, Acinetobacter baumannii, Pseudomonas aeruginosa. The bacteria will be reactivated and subjected to the Broth Microdilution test, to determine the Minimum Inhibitory Concentration (MIC) of ZnO-NP against the mentioned bacteria. MIC values will be statistically compared using the non-parametric Kruskal Wallis test followed by the Student Newman-Keuls test and will be considered statistically different when p<0.05. The development of the natural latex biomembrane with ZnO nanoparticles (ZnO-NPs) will be carried out using the method of adding ZnO-NPs to the latex in suspension in two quantities greater than the MIC results. The suspension will be placed in Petri dishes and polymerized in an oven at 40ºC. The antimicrobial potential of the new Biomembrane will be evaluated through the S. aureus bacterial biofilm formation experiment, where the reduction of biofilm biomass, reduction of metabolic activity and inhibition of biofilm growth will be evaluated. The results of biomembranes without nanoparticles and in the 2 concentrations will be compared, using the same statistical procedures described previously.