Abstract: Abstract:Objective To explore the in vitro and in vivo antibacterial activities of Impatiens Balsamina water extraction and to provide the pharmacological reference for seeking the new antibacterial drug. Methods The in vitro experiment was divided into negative control group (group A),penicillin control group (group B),streptomycin control group (group C),different doses of Impatiens Balsaminawater extraction (0.01,0.10,1.00 and 10.00 g/mL) groups(group D-G).The Impatiens Balsaminawater extraction was prepared by impregnation.The in vitro inhibitory effects of the Impatiens Balsamina water extraction on Staphylococcus aureus,Escherichia coli,Candida albicans,Proteus sp.,Pseudomonas aeruginosa,Bauman Acinetobacter，and Klebsiella pneumoniae were assayed by groove and paper disc antibacterial experiment.The in vivo experiment was divided into negative control group (group A),different doses of Impatiens Balsamina water extraction(0.5，5.0 and 50.0 g/kg) groups (group B-D).The in vivo inhibitory effects of Impatiens Balsamina water extraction were detected with Staphyloccocus aureus and Escherichia coli as index,the mice were given  Impatiens Balsamina water extraction by gavage for 7 d,then the mice were intraperitoneally injected with Staphyloccocus aureus and Escherichia coli suspension.The in vivo antibacterial activity of Impatiens Balsamina water extraction were detected by observing the mortality rate in mice.Results The in vitro assay showed that when the concentration was over 1　g/mL,the Impatiens Balsamina water extraction exhibited inhibitory effects on all the 7 kinds of pathogenic bacteria,the individual diameters of the inhibition zone were greater than that in negative control group and the difference was statistically significant (P<0.05).The in vivo assay showed that when the concentration was over 5　g?kg-1,the water extraction had antibacterial activity against Staphyloccocus aureus and Escherichia coli.The mortality rate of mice in Impatiens Balsamina water extraction group was significantly decreased (55.6%) compared with negative control group (88.9%).Conclusion Impatiens Balsamina water extraction contains the antibacterial ingredient.

Key words: water extraction, antibacterial activity, Impatiens Balsamina