Abstract:

Objective To study the antibacterial activities of 8 kinds of Chinese herbal medicines to clinical common resistant and non-resistant isolates in vitro. Methods Totally,8 kinds of Chinese herbal medicines,including Rhizoma coptidis,Honeysuckle,Chrysanthemum indicum,Forsythia,Rhubarb,Cordate houttuynia,Rhizoma phragmitis and Andrographis paniculata,were selected and extracted with pure water concentrated with1 g/mL. Staphylococcus aureus ATCC 29213,methicillin-sensitive Staphylococcus aureus（MSSA）,methicillin-resistant Staphylococcus aureus（MRSA）,Escherichia coli ATCC 25922,Escherichia coli ATCC 35218 which produced extended-spectrum beta-lactamase（ESBL）,ESBL（-） Escherichia coli and ESBL（+） Escherichia coli were used to determine the minimum inhibitory concentration（MIC） and minimum bactericidal concentration（MBC） in vitro by liquid dilution method. Results The MIC of Rhizoma coptidis,Honeysuckle,Chrysanthemum indicum,Forsythia and Rhubarb to Staphylococcus aureus ATCC 29213,MSSA and MRSA were 7.81-125.00 mg/mL.The MIC of Rhizoma coptidis and Honeysuckle to Escherichia coli ATCC 25922,Escherichia coli ATCC 35218 produced ESBL,ESBL（-） Escherichia coli and ESBL（+） Escherichia coli were 62.5-250.0 mg/mL. The MBC of Rhizoma coptidis to Staphylococcus aureus ATCC 29213,MSSA and MRSA were 15.62-62.50 mg/mL,and the MBC of Rhizoma coptidis to Escherichia coli ATCC 25922 and Escherichia coli ATCC 35218 produced ESBL,ESBL（-） Escherichia coli and ESBL（+） Escherichia coli were 250-500 mg/mL. The bacteriostatic action of the same kind of Chinese herbal medicine to resistant and non-resistant isolates had no statistical significance. Conclusions Rhizoma coptidis,Honeysuckle,Chrysanthemum indicum,Forsythia and Rhubarb have strong bacteriostatic action to Staphylococcus aureus ATCC 29213,MSSA and MRSA. Rhizoma coptidis and Honeysuckle also have certain bacteriostatic action to Escherichia coli ATCC 25922,Escherichia coli ATCC 35218 produced ESBL,ESBL（-）Escherichia coli and ESBL（+） Escherichia coli.

Key words: Chinese herbal medicine, Drug resistant isolate, Non-drug resistant isolate, Antibacterial activity