In Vitro Activity of Epigallocatechin Gallate and Quercetin Alone and in Combination versus Clinical Isolates of Methicillin-Resistant Staphylococcus aureus.

Topical infections can become life threatening in immunocompromised patients. However, fewer treatments are available as multi-drug-resistant bacteria become more common. The natural compounds epigallocatechin gallate (1) and quercetin (2) alone and in combination were tested as potential antimicrobial clinical therapies. Strong antimicrobial activity was produced by 1 alone against methicillin-resistant Staphylococcus aureus, and activity was significantly increased in the presence of 2. A synergistic interaction was observed between the two compounds. Kill kinetics indicate the combination is bactericidal over 24 h.