Phenolic Compounds in Antimicrobial Therapy

Long-term treatment with several conventional antibiotics can cause harmful side effects that can be alleviated by antioxidant therapy. Phenolic compounds (PCs) are the best source of antioxidants, and to identify the most suitable polyphenols for use as a supportive supplement during antibiotic therapy, this study screened a series of PCs to establish their antibacterial potential, including their biofilm and β-lactamase inhibition activity. Several PCs were tested for antibacterial activity against Staphylococcus epidermidis and Pseudomonas aeruginosa. Among them, tannic acid, epigallocatechin gallate, rutin, and eugenol showed the highest antibacterial activity. Epigallocatechin gallate, tannic acid, quercetin, and epicatechin inhibited a significant level of β-lactamase activity. Tannic acid and epigallocatechin gallate presented the highest β-lactamase inhibition potential in both in vitro and in silico analysis. In the present work, these two PCs were the most active agents, presenting both antibacterial activity and β-lactamase and biofilm inhibition ability.