Coptidis Rhizoma: a comprehensive review of its traditional uses, botany, phytochemistry, pharmacology and toxicology

Wang, Jin; Wang, Lin; Lou, Guan-Hua; Zeng, Hai-Rong; Hu, Ju; Huang, Qin-Wan; Peng, Wei; Yang, Xiang-Bo

Berberine can inhibit Gram-positive (G þ ) bacteria such as Streptococcus agalactiae, Staphylococcus aureus, S. mutans, Bacillus anthracis, S. suis, and Enterococcus faecium (Choi et al. 2007; Fan et al. 2008; Wang et al. 2014; Peng et al. 2015) ; and Gram-negative (G -) bacteria such as Actinobacillus pleuropneumoniae , Shigella dysenteriae (Kong et al. 2010) , and Escherichia coli (Boberek et al. 2010) . Interestingly, alkaloids isolated from CR, especially epiberberine, can act as urease inhibitors to treat Helicobacter pylori infection . In 2014, Chen et al. reported that CR extracts (CRE) significantly inhibited Salmonella typhimurium with a minimum bactericidal concentration (MBC) of 12.5 mg/mL. Another study reported that although CRE had no effect on bacteria such as Pseudomonas aeruginosa, Proteus mirabilis, and Proteus vulgaris, after processing with ginger, it showed a marked inhibitory effect against these bacteria, especially P. aeruginosa (Li 2015) . Previous studies revealed that the antibacterial effects of CR and its active constituents were attributed to damaging the cell membrane, inhibiting protein and DNA synthesis, blocking bacterial division and development, and disturbing the formation of the Z-rings to inhibit the cell division protein FtsZ Xue D et al. 2015; Ming et al. 2016) . The antibacterial effect of CR alkaloids against G þ bacteria was stronger than that against Gbacteria, which could be explained by different the cell membrane structures of the pathogens (Yong et al. 2007 ). performed a comprehensive analysis including the growth rate constant k, maximum power output of the log phase P m,log , total heat output of the log phase Q t,log , generation time t g , growth inhibitory ratio I, and half-inhibitory concentration of the drugs (IC 50 ), and revealed that the antibacterial activities against E. coli of the four alkaloids from CR were in the order of berberine > coptisine > palmatine) jatrorrhizine.