Resumo (PT):
Abstract (EN):
In recent decades, the escalating trend of multidrug-resistant bacteria has posed a severe threat
to global public health by limiting therapeutic options and increasing mortality rates [1, 2].
Consequently, novel treatment strategies have been under exploitation, being plant-derived
compounds, i.e., phytochemicals, an emerging promise to face this challenging issue as they offer
a panoply of advantages - from structural diversity and multiple modes of action to safety [3, 4].
In this study, five phytochemicals (linalool, verbenone, chrysin, crocin, and papaverine) were used
to assess their antimicrobial activity and then their potentiation effect on ten antibiotics from
different classes (ciprofloxacin, methicillin, oxacillin, amoxicillin, erythromycin, gentamicin
sulfate, tobramycin, tetracycline, fusidic acid, and mupirocin). The minimum inhibitory
concentrations (MIC) and minimum bactericidal concentrations (MBC) of all phytochemicals were
determined against Escherichia coli CECT 102 and Staphylococcus epidermidis ATCC 35984 using
the microdilution assay. Linalool exhibited promising results, with MIC and MBC values of 800
μg/mL for E. coli and a MIC of 400 μg/mL for S. epidermidis. Similarly, verbenone showed
significant potential with a MIC of 2000 μg/mL for both bacteria. The remaining compounds
showed MIC and MBC values exceeding 2000 μg/mL. Moreover, to initially appraise the
synergistic effects between the phytochemicals and antibiotics, the disc diffusion method was
used, and results revealed a clear potentiation effect for verbenone, linalool, crocin and chrysin
when combined with erythromycin. These molecules when combined as natural deep eutectic
solvents further demonstrated promising effects against the bacteria in planktonic state and
biofilms. To date, this study has revealed promising results, supporting phytochemicals as agents
capable of modifying resistance and their great prospect in combating this pressing global
predicament.
Language:
English
Type (Professor's evaluation):
Scientific