Abstract: The aim of this study was to investigate the antibacterial and inhibitory activities of the different extracts of Zanthoxylum dissitum Hemsl Stem on the proliferation of MCF-7 cells.All the extracts were evaluated for their antibacterial activities against three gram-negative bacteria: Escherichia coli,Pseudomonas aeruginosa, Helicobacter pylori and four gram-positive bacteria: Staphylococcus epidermidis, Bacillus subtilis, Micrococcus luteus,Staphylococcus aureus using microporous turbidimetry method.In addition,their cytotoxic activities were measured against breast cancer cells MCF-7 by MTT assay. The results showed that all the extracts displayed great inhibition effects on the tested bacteria,especially those gram-positive bacterial,the chloroform part showed the highest activity,notably;All of the parts showed significant inhibitory effects on the proliferation of MCF-7 cells,among which,the chloroform part exhibited highese antineoplastic activities with IC₅₀ of 2.35±0.97×10^-1 mg/mL.Moreover,the IC₅₀ of n-butanol part was 3.19±0.54×10^-1 mg/mL.However,the ethyl acetate extract was weakest with IC₅₀ of 6.47±0.94×10^-1 mg/mL.These results suggested that the chloroform and n-butanol extract possibly contained compounds with significantly antibacterial and antitumor activities.This research provided a scientific basis for the development of Z.dissitum.

Key words: Zanthoxylum dissitum Hemsl., extracts, antibacterial, breast cancer