Antimicrobial Activity of Kalanchoe blossfeldiana and Paederia foetida Plant Leaves’ Extracts Against Some Selected Bacterial Strains

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