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Assessment of the anti-virulence potential of extracts from four plants used in traditional Chinese medicine against multidrug-resistant pathogens

Authors Pu, Zhonghui; Tang, Huaqiao; Long, Nana; Qiu, Min; Gao, Mingxiang; Sun, Fenghui; Dai, Min

Journal BMC COMPLEMENTARY MEDICINE AND THERAPIES , OCT 19 2020,1:20

DOI 10.1186/s12906-020-03114-z PubMed 33076882

Abstract Background Multidrug-resistant pathogens are resistant to many antibiotics and associated with serious infections.Amomum tsaokoCrevost et Lemaire, Sanguisorba officinalis, Terminalia chebulaRetz andSalvia miltiorrhiza Bge, are all used in Traditional Chinese Medicine (TCM) against multidrug-resistant pathogens, and the purpose of this study was to evaluate the antibacterial and anti-virulence activity of extracts derived from them. Methods The antibacterial activity of ethanol and aqueous extracts from these four plants was examined against several multi-drug resistant bacterial strains, and their anti-virulence potential (including quorum quenching activity, biofilm inhibition, and blocking production of virulence factor delta-toxin) was assessed against differentS. aureusstrains. The chemical composition of the most effective extract was determined by LC-FTMS. Results Only extracts fromS. officinalisandA. tsaokowere shown to exhibit limited growth inhibition activity at a dose of 256 mu g center dot mL-1. TheS. officinalisethanol extract, the ethanol and aqueous extract ofA. tsaoko, and the aqueous extract ofS. miltiorrhizaall demonstrated quorum quenching activity, but didn''t significantly inhibit bacterial growth. The ethanol extract ofS. officinalisinhibited bacterial toxin production and biofilm formation at low concentrations. Chemical composition analysis of the most effective extract ofS. officinalisshowed that it mainly contained saponins. Conclusions The most active extract tested in this study was the ethanol root extract ofS. officinalis. It inhibited delta-toxin production and biofilm formation at low concentrations and saponins may be its key active components. While the four plants showed no direct antibacterial effects, their anti-virulence properties may be key to fighting bacterial infections.

Species covered 丹参 Salvia miltiorrhiza 地榆 Sanguisorba officinalis 诃子 Terminalia chebula 草果 Amomum tsaoko