Ecological Studies on Microorganisms Producing Antimicrobial Agents from Different Soil Types

In the present study, a trial was done to find out the distribution of antimicrobial agent producing bacteria from different soil types collected from different regions of Egypt governorates. Physical and chemical properties of soil samples were determined and isolation of different bacterial colonies from different soil types was also carried out. All the isolated bacterial colonies were then screened for their antimicrobial activity against the human pathogenic bacteria (Gram negative and positive), plant pathogen bacteria and fungi. The highest number was from Tanta, Sheben El-Kom and El-Mansora (33.33%) and El-Tahrir and Ismailia (27.78%) followed by Sedi-Salem and Kafr-El-Sheikh (16.67%), EL-Tall El Kebeer (16.67%) and the least isolates active from Borg El-Arab and El-America (5.56). According to the spectrum of 18 active bacteria, it was found that only three bacterial isolates SOF12, SMF4 and AMF11 showed the highest antimicrobial activity against all the tested microorganisms with high potential inhibitory activity against both filamentous fungi. This study indicates that microorganisms isolated from Salt affected soil from Kafr-El-Sheikh, sandy loam soil from Ismailia and alkaline soil from EL-Tall El Kebeer, respectively could be an interesting source of antimicrobial bioactive substances.