Abstract: In order to explore the optimal extraction conditions and the antibacterial activity of total alkaloids from Bozhou Peony Paeonia lactiflora, single factor experiments followed by orthogonal tests were applied based on our preview study,and then preliminary in vitro antibacterial activities were evaluated by disc diffusion assay. The results showed that the optimal extraction conditions were as follows:methanol concentration of 60%,extraction time of 3 h,extraction temperature of 60 ℃,and the ratio of solid-liquid of 1:20.In addition,the total alkaloid extract showed inhibitory activities against all the 4 investigated bacteria Excherichia coli,Staphylococcus aureus, Saccharomyces cerevisiae and Aspergillus niger with the following sequence:S.aureus >S.cerevisiae>A.niger>E.coli.

Key words: Bozhou Peony Paeonia lactiflora, alkaloids, antibacterial activity