Background: Antioxidants are multifaceted molecules playing a crucial role in several
cellular functions. There is by now a well-established knowledge about their involvement in numerous
processes associated with aging, including vascular damage, neurodegenerative diseases and
cancer. An emerging area of application has been lately identified for these compounds in relation to
the recent findings indicating their ability to affect biofilm formation by some microbial pathogens,
including Staphylococcus aureus, Streptococcus mutans, and Pseudomonas aeruginosa.
Methods: A structured search of bibliographic databases for peer-reviewed research literature was
performed using a focused review question. The quality of retrieved papers was appraised using
Results: One hundred sixty-five papers extracted from pubmed database and published in the last
fifteen years were included in this review focused on the assessment of the antimicrobial and antibiofilm
activity of antioxidant compounds, including vitamins, flavonoids, non-flavonoid polyphenols,
and antioxidant polymers. Mechanisms of action of some important antioxidant compounds,
especially for vitamin C and phenolic acids, were identified.
Conclusions: The findings of this review confirm the potential benefits of the use of natural antioxidants
as antimicrobial/antibiofilm compounds. Generally, gram-positive bacteria were found to be
more sensitive to antioxidants than gram-negatives. Antioxidant polymeric systems have also been
developed mainly derived from functionalization of polysaccharides with antioxidant molecules.
The application of such systems in clinics may permit to overcome some issues related to the systemic
delivery of antioxidants, such as poor absorption, loss of bioactivity, and limited half-life.
However, investigations focused on the study of antibiofilm activity of antioxidant polymers are still
very limited in number and therefore they are strongly encouraged in order to lay the foundations for
application of antioxidant polymers in treatment of biofilm-based infections.