Antibacterial activity of Butia odorata extracts against pathogenic bacteria

Currently, synthetic preservatives are added to foods to increase their microbiological safety, but the demand for foods free of these agents is on the rise. Butia odorata Barb. Rodr. is a tree native to southern South America, with fruits rich in bioactive compounds. In this investigation, hexane (BHE) and methanol (BME) extracts of B. odorata fruit were evaluated for their antibacterial activity against three Gram-positive (Listeria monocytogenes, Staphylococcus aureus, and Bacillus cereus) and three Gram-negative bacteria (Salmonella Typhimurium, Escherichia coli O157:H7, and Pseudomonas aeruginosa) by the agar diffusion method. Antibacterial activity of both B. odorata extracts was confirmed, with BHE showing inhibition zones significantly higher than BME, and with higher activity against Gram-negative bacteria. E. coli O157:H7 was the most sensitive microorganism, being inhibited at a minimum bactericidal concentration (MBC) of 3 mg.mL-1. Of the Gram-positive bacteria, S. aureus was the most susceptible (MBC 11 mg.mL-1). γ-sitosterol was the major compound, constituting 22% of the total composition.