RASHID ABDALLA AHMED HASSOUNA2018-08-022018-08-022005http://hdl.handle.net/123456789/12391A thesis submitted to Al Neelain University Faculty of Medical Laboratory Sciences Department ofMicrobiology .Abstract This thesis investigates the antimicrobial activity of some Sudanese plants used in folk-medicine against Mtuberculosis. Preliminary screening was carried out using twenty plants, which grow in Sudan and used in folk~medicine for their effects on some microbial infections. The screening revealed that the petroleum ether extracts (non-polar extracts) possess no activity at the concentrations screened, while the methanolic extracts (polar-extracts) of these plants have a weak activity against M tuberculosis. An experiment was designed to compare the in-vitro activity of two drugs of choice used for treatment of tuberculosis (Streptomycin and Rifampcin) with the activity of the plants’ extracts. A series of in-vitro sensitivity tests were conducted to evaluate the effect of combined therapy, consisting of the methanolic extract of each plant plus Streptomycin on Mtuberculosis. The results revealed that thirteen methanolic extracts have a positive effect on M tuberculosis when mixed with Streptomycin. The minimum inhibitory concentration (MIC) of each extract was determined. The results indicated that the most effective plants’ extracts are Asphodelus tenuzfolius (Burwag), Nigella sativa L (Black Kamoon) and Kigelia afiicana (Um-Shotour).enANTIMICROBIAL ACTIVITYThesis