Antibacterial activity and mechanism of the ethanol extracts from Sonchus brachyotus DC.

作者:Li, Xiu-Mei*; Liu, Jing; Du, Yong-Kai; Wen, Zhi-Guo; Wang, Ji-Tong; Yang, Pei-Long*
来源:International Journal of Food Properties, 2017, 20(12): 2923-2931.
DOI:10.1080/10942912.2016.1261152

摘要

Sonchus brachyotus DC. (S. brachyotus) is considered a vegetable, and rarely considered to be medicinal. However, S. brachyotus is used as a kind of traditional folk herb in Europe. Pharmacological studies are necessary in order to provide a scientific basis to substantiate their use. This study investigated the antimicrobial effect and mechanism of action of the ethanol extract from S. brachyotus. Ethanol extract from S. brachyotus exhibited antimicrobial activity against Escherichia coli, Enterobacter cloacae, Klebsiella pneumonia, Salmonella enteric, Staphylococcus aureus, and Micrococcus luteus; this is especially so in the case of E. coli. This study investigated the novel antibacterial mechanism of ethanol extract from S. brachyotus that shows an apoptosis-like response in E. coli. At all the tested concentration, it was found that ethanol extract from S. brachyotus-treated E. coli cells displayed various apoptotic markers, such as membrane damage, reactive oxygen species accumulation, and membrane depolarization. Expression of caspases protein, which mediates a bacterial apoptosis-like response, was also increased by ethanol extract from S. brachyotus. In order to evaluate the influence of caspases on the appearance of other apoptotic markers, phosphatidylserine exposure and DNA fragmentation were detected and compared with untreated and with ethanol extract from S. brachyotus. These characteristics were detected in E. coli cells, but not in untreated, with ethanol extract from S. brachyotus. In conclusion, the data obtained demonstrated that ethanol extract from S. brachyotus induces an apoptosis-like response in E. coli that associates with caspase-like protein.

  • 出版日期2017
  • 单位中国农业科学院