Goldenseal (Hydrastis canadensisL.) Extracts Synergistically Enhance the Antibacterial Activity of Berberine via Efflux Pump Inhibition

Abstract

Goldenseal (Hydrastis canadensis L.) is used to combat inflammation and infection. Its antibacterial activity in vitro has been attributed to its alkaloids, the most abundant of which is berberine. The goal of these studies was to compare the composition, antibacterial activity, and efflux pump inhibitory activity of ethanolic extracts prepared from roots and aerial portions of H. canadensis. Ethanolic extracts were prepared separately from roots and aerial portions of six H. canadensis plants. Extracts were analyzed for alkaloid concentration using LC-MS and tested for antimicrobial activity against Staphylococcus aureus (NCTC 8325-4) and for inhibition of ethidium bromide efflux. Synergistic antibacterial activity was observed between the aerial extract (FIC 0.375) and to a lesser extent the root extract (FIC 0.750) and berberine. The aerial extract inhibited ethidium bromide efflux from wild-type S. aureus, but had no effect on the expulsion of this compound from an isogenic derivative deleted for norA. Our studies indicate that the roots of H. canadensis contain higher levels of alkaloids than the aerial portions, but the aerial portions synergize with berberine more significantly than the roots. Furthermore, extracts from the aerial portions of H. canadensis contain efflux pump inhibitors, while efflux pump inhibitory activity was not observed for the root extract. The three most abundant H. canadensis alkaloids, berberine, hydrastine and canadine, are not responsible for the efflux pump inhibitory activity of the extracts from H. canadensis aerial portions.

Berberine inhibits the MexXY‑OprM efflux pump to reverse imipenem resistance in a clinical carbapenem‑resistant Pseudomonas aeruginosa isolate in a planktonic state

“…The present study did not assess all efflux pump systems, so that the possible participation of efflux pumps other than MexXY-OprM cannot be ruled out. Several studies indicated that the weak antibacterial effect of BBR was mainly due to the low accumulation of intracellular BBR, and drugs that increased the intracellular BBR concentration were able to promote the antibacterial effect of BBR (25)(26)(27)(28). The present study observed that IMP significantly increased the intracellular BBR fluorescence.…”

Fluconazole Assists Berberine To Kill Fluconazole-Resistant Candida albicans

“…BBR has been reported as an isoquinoline alkaloid with poor bioavailability (43). Some studies have demonstrated that the weak antibacterial effect of BBR was mainly due to the low concentration of intracellular BBR, and agents which could promote the ingression of BBR were able to enhance the antibacterial effect of BBR (29,(44)(45)(46). In this study, we postulated that FLC could promote the ingression of BBR.…”

Medicinal plants in the treatment ofHelicobacter pyloriinfections

“…There is some justification in the scientific literature for the effectiveness of Hydrastis canadensis L. (Ranunculaceae) and its constituents as antidiarrheal and antimicrobial agents (Cybulska et al, 2011;Ettefagh et al, 2011;Junio et al, 2011). Traditionally, H. canadensis was used by the Iroquois for gastrointestinal issues .…”