Methicillin-resistant S. aureus (MRSA) are a threat to public health as they frequently reveal
a multidrug-resistant pattern. Researchers all over the world are on an urgent hunt for new treatments
to help fight infections before antibiotics become obsolete, and some natural alternatives, such as
polyphenols, have already exhibited therapeutic properties. Therefore, this study aimed to determine
the phenolic profile, antioxidant capacity, and antimicrobial activity against MRSA of the leaf, fruit,
and stem bark extracts of Platanus hybrida. The polyphenols were extracted with a water/ethanol
(20:80) mixture and the methodology included HPLC-DAD, DPPH, FRAP, and CuPRAC. To address
this issue from a One Health perspective, the Kirby–Bauer disc diffusion method was performed
against nine MRSA strains from three different sources (livestock, wild animals, and humans).
Fourteen phenolics were identified and the leaf extract showed the highest phenolic content, followed
by the fruit extract. The leaf extract also showed the highest antioxidant capacity while the fruit
extract had the lowest antioxidant capacity. Both leaf and fruit extracts inhibited the growth of strains
from all sources, while the stem bark extract did not inhibit the growth of human strains. This work
highlights the complex chemical composition and the antioxidative and antimicrobial potential of
extracts derived from P. hydrida.
This work was supported by the projects UIDB/CVT/00772/2020 and LA/P/0059/2020
funded by the Portuguese Foundation for Science and Technology (FCT). This work was also supported
by the Associate Laboratory for Green Chemistry-LAQV, which is financed by national funds from
FCT/MCTES (UIDB/50006/2020 and UIDP/50006/2020) funded by FCT. The authors acknowledge
the financial support of FCT by national funds under the project UIDB/04033/2020. Vanessa Silva is
grateful to FCT for financial support through PhD grant SFRH/BD/137947/2018. To FCT, Portugal for
financial support through national funds FCT/MCTES to CIMO (UIDB/00690/2020) and the contract of
L. Barros through the institutional scientific employment program-contract. This work was supported.
