Antibacterial Activities and Antibacterial Mechanism of Polygonum cuspidatum Extracts against Nosocomial Drug-Resistant Pathogens

Molecules

Pai-Wei Su¹  Cheng-Hong Yang²  Jyh-Ferng Yang¹  Pei-Yu Su¹  Li-Yeh Chuang¹ 

[1] Institute of Biotechnology and Chemical Engineering, I-Shou University, Kaohsiung 840, Taiwan; E-Mails:;Department of Electronic Engineering, National Kaohsiung University of Applied Sciences, Kaohsiung 807, Taiwan; E-Mail:

关键词: Polygonum cuspidatum;    antibacterial activity;    clinical drug-resistant bacteria;   

DOI  :  10.3390/molecules200611119

来源: mdpi

【 摘 要 】

Recently, drug resistance due to the extensive abuse and over-use of antibiotics has become an increasingly serious problem, making the development of alternative antibiotics a very urgent issue. In this study, the Chinese herbal medicine, Polygonum cuspidatum, was extracted with 95% ethanol and the crude extracts were further purified by partition based on solvent polarity. The antimicrobial activities of the extracts and fractions were determined by the disk diffusion and minimum inhibitory concentration (MIC) methods. The results showed that the ethyl ether fraction (EE) of the ethanol extracts possesses a broader antimicrobial spectrum and greater antimicrobial activity against all of the tested clinical drug-resistant isolates, with a range of MIC values between 0.1–3.5 mg/mL. The active extract showed complete inhibition of pathogen growth and did not induce resistance to the active components. In addition, according to scanning electron microscope observations, EE resulted in greater cell morphological changes by degrading and disrupting the cell wall and cytoplasmic membrane, whereby ultimately this cell membrane integrity damage led to cell death. In conclusion, the EE extracts from Polygonum cuspidatum may provide a promising antimicrobial agent for therapeutic applications against nosocomial drug-resistant bacteria.

【 授权许可】

CC BY   
© 2015 by the authors; licensee MDPI, Basel, Switzerland.