Abstract: This research was aimed to investigate four kinds of Holly bark extracts combined with antimicrobial drugs to induce bacteria in vitro antibacterial activity. Four kinds of Holly bark extracts were prepared, the bacterial passage of drug-resistant Escherichia coli induced by Holly bark extracts combined with antimicrobial drugs were tested by 96-well reaction plate twice micro-dilution method. Four kinds of Holly bark extracts combined with antimicrobial drugs to induce bacteria passage for drug-resistant Escherichia coli had different antibacterial activities, in which extractsⅠ,Ⅲ combination with antimicrobial drugs had the best effect. Holly bark extracts Ⅰ,Ⅲ combined with antimicrobial drugs to induce bacterial passage had anti-drug-resistant bacteria effect in vitro.

Key words: Holly bark; extract; combined induction; bacterial passage; antimicrobial activity