Ocotea odorifera extract: antimicrobial and antibiofilm activities, phytochemical aspects, cytotoxicity and anti-inflammatory potential of an endangered plant species.

Abstract

Exploring natural products in drug discovery can provide new options for effective treatments for infectious diseases. Biofilms are frequently not considered in most studies of antimicrobial activity, despite their relevance in microbial pathogenicity and resistance to antimicrobials. Here we investigated the antimicrobial and antibiofilm potentials of Ocotea odorifera, a Brazilian endangered species, against clinical isolates of Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. We assessed the activity of the extract using minimal inhibitory concentration (MIC), minimal bactericidal concentration (MBC) and minimal biofilm eradication concentration (MBEC) assays, and a skin infection model. We evaluated the cytotoxicity of the extract in BGM cells and assessed its anti-inflammatory potential. Phytochemical profiling was conducted using classical methods and UHPLC-HRMS/MS. The extract was active against the planktonic cells of all species (MIC = 8 µg/mL, variable MBC values), and eradicated biofilms of S. aureus (MBEC = 256 µg/mL). Phytochemical analysis indicated that erucamide was the most abundant compound in the sample, which is being described for this species for the first time along with other phytomolecules. The extract did not show cytotoxicity and presented anti-inflammatory activity comparable to meloxicam. Our data provides evidence on the antimicrobial activity of O. odorifera, especially its antibiofilm potential, and highlights the need of preservation of endangered species as a valuable source of bioactive metabolites of clinical interest. More studies are necessary to investigate these pharmacological properties in vivo.