Anti-biofilm potential of phenolic acids: the influence of environmental pH and intrinsic physico-chemical properties

• Published in: Biofouling (Chur, Switzerland) Vol. 32; no. 8; pp. 853 - 860
• Main Authors: Silva, Sara, Costa, Eduardo M., Horta, Bruno, Calhau, Conceição, Morais, Rui M., Pintado, M. Manuela
• Format: Journal Article
• Language: English
• Published: England Taylor & Francis 13.09.2016
• Subjects: Anti-Bacterial Agents - chemistry; Anti-Bacterial Agents - pharmacology; anti-biofilm activity; Biofilms - drug effects; Biomass; Escherichia coli; Escherichia coli - drug effects; Escherichia coli - metabolism; Escherichia coli - physiology; Hydrogen-Ion Concentration; Hydroxybenzoates - chemistry; Hydroxybenzoates - pharmacology; Inhibition; Links; Methicillin-Resistant Staphylococcus aureus - drug effects; Methicillin-Resistant Staphylococcus aureus - metabolism; Methicillin-Resistant Staphylococcus aureus - physiology; Microbial Sensitivity Tests; Molecular Weight; MRSA; MRSE; Phenolic acids; Polarity; Staphylococcus aureus; Staphylococcus epidermidis; Staphylococcus epidermidis - drug effects; Staphylococcus epidermidis - metabolism; Staphylococcus epidermidis - physiology; MRSE; Escherichia coli; Phenolic acids; anti-biofilm activity; MRSA
• ISSN: 0892-7014; 1029-2454; 1029-2454
• DOI: 10.1080/08927014.2016.1208183

Phenolic acids are a particular group of small phenolic compounds which have exhibited some anti-biofilm activity, although the link between their activity and their intrinsic pH is not clear. Therefore, the present work examined the anti-biofilm activity (inhibition of biomass and metabolic activity) of phenolic acids in relation to the environmental pH, as well as other physico-chemical properties. The results indicate that, while Escherichia coli was not inhibited by the phenolic acids, both methicillin resistant Staphylococcus aureus and methicillin resistant Staphylococcus epidermidis were susceptible to the action of all phenolic acids, with the pH playing a relevant role in the activity: a neutral pH favored MRSE inhibition, while acidic conditions favored MRSA inhibition. Some links between molecular polarity and size were associated only with their potential as metabolic inhibitors, with the overall interactions hinting at a membrane-based mechanism for MRSA and a cytoplasmic effect for MRSE.