We evaluated the chemical composition, toxicity, and antibacterial activity of Schinus terebinthifolia (SCH), Eugenia uniflora (EUG), Persicaria hydropiperoides (PER), Equisetum hyemale (EQU), Solidago chilensis (SOL), and Baccharis trimera (BRA). These plants were tested (7.5-0.01 mg/mL) against Gram-positive (G+; n = 32) and Gram-negative (G-; n = 26) isolates from animals (M07-A9, CLSI). Antibiogram (disk diffusion), chromatographic analysis (UPLC), and toxicity assay (HET-CAM) were also performed. A high incidence of resistance was noted, in which 18.4% (07/38) of G+ (Staphylococcus intermedius/Enterococcus faecium) and 17.7% (06/34) of G- (Pseudomonas aeruginosa/Escherichia coli/Proteus mirabilis) were multidrug-resistant. All bacteria were sensitive (MIC50) to SCH (both 3.75 mg/mL), EUG (3.75 mg/mL and 7.5 mg/mL, respectively) and PER (both 7.5 mg/mL). SCH/EUG/PER highlighted as antibacterial, probably due to the major compounds (ethyl gallate, quinic acid, quercetin). These extracts showed normal embryonic development (SCH/EUG: 7.5-0.94 mg/mL). These findings highlighted the promising use of native plants for therapeutic purposes.
Keywords: Antimicrobial resistance; Eugenia uniflora; Schinus terebinthifolia; chromatography; medicinal plants; toxicity.