title: Antibacterial effects of theaflavin and synergy with epicatechin against clinical isolates of Acinetobacter baumannii and Stenotrophomonas maltophilia.
abstract: Stenotrophomonas maltophilia and Acinetobacter baumannii are recognised as important nosocomial pathogens; however, due to their intrinsic resistance to multiple antibiotics, treatment options are limited. Polyphenols from black tea have been shown to possess antibacterial action. In this study, the antibacterial effects of various concentrations of theaflavin as well as combinations of theaflavin and epicatechin were determined using the disk diffusion assay. The results showed strong antibacterial activity of theaflavin against eight clinical isolates of S. maltophilia and A. baumannii. Significant synergy (P≤0.05) was also observed between theaflavin and epicatechin against all isolates. Although the mechanisms for this activity and synergy are not well understood, the clinical potential is clear and further research is recommended to determine the modes of action.
authors: Department of Chemistry, University of Hull, Hull HU6 7RX, UK.
authors: J W
authors: JW
authors: Betts
authors: S M
authors: SM
authors: Kelly
authors: S J
authors: SJ
authors: Haswell
mesh_terms: D000151:Acinetobacter Infections / Q000188:drug therapy / Q000382:microbiology; D040981:Acinetobacter baumannii / Q000187:drug effects* / Q000302:isolation & purification; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D044946:Biflavonoids / Q000494:pharmacology*; D002392:Catechin / Q000494:pharmacology*; D004357:Drug Synergism; D016905:Gram-Negative Bacterial Infections / Q000188:drug therapy / Q000382:microbiology; D006801:Humans; D008826:Microbial Sensitivity Tests; D020615:Stenotrophomonas maltophilia / Q000187:drug effects* / Q000302:isolation & purification
chemical_list: D000900:Anti-Bacterial Agents; D000975:Antioxidants; D044946:Biflavonoids; C056068:theaflavin; D002392:Catechin