There is an alternative approach to control the infectious diseases caused by pathogenic bacteria, especially resistant bacteria. This study was designed to determine the antimicrobial activities of Kalanchoe blossfeldiana and Paederia foetida plants’ extracts against some selected bacterial strains. K. blossfeldiana and P. foetida leaves were extracted in methanol. In vitro antibacterial activities were evaluated against 12 bacterial strains including, Staphylococcus gallinarum, Staphylococcus sciuri, Streptococcus constellatus, Streptococcus iniae, Aeromonas diversa, Xanthomonas campestris, Xanthomonas axonopodis, Siccibacter colletis, Edwardsiella anguillarum, Aeromonas cavernicola, Enterobacter xiangfangensis, and Vibrio rotiferianus. Antimicrobial activities were screened by disk diffusion method. In addition, minimum inhibitory concentration (MIC) was determined using broth dilution method. Data were analyzed using SPSS 16 statistical software. In antimicrobial screening, both the plant extracts showed highest inhibition (15 mm zone diameter) against S. gallinarum at the concentration of 20 μg/disk and 15 μg/disk, respectively. In the MIC test, both K. blossfeldiana and P. foetida leaves’ extracts showed the lowest MIC value of 100 μg/ml on V. rotiferianus and S. iniae, respectively. From the above findings, it can be concluded that the extracts may be used as natural antibacterial agent for the treatment of some bacterial diseases. Further investigations on the chemical composition and possible isolation of active ingredients are warranted.
