Abstract
The ability of 35 isolates from soil which belong to the endo-spore forming bacteria Thermoactinomyces vulgaris , Thermoactinomyces intermedius , Bacillus mycoides and Paenibacillus spp. to produce antibiotics against some gram positive bacteria Corynebacterium spp. , Staphylococcus aureus subsp.aureus , Bacillus cereus and gram negative bacteria Pseudomonas aeruginosa , Proteus mirabilis , Klebsiella oxytoca , Klebsiella spp. were card out , The antibiotics separated from three strains which gave highest activity against bacteria under study, two strains from Paenibacillus spp. and one strain form B.mycoides, by using thin-layer Chromatographic technique , the spots distinguished by UV and Running factor (Rf) compared with standard antibiotics , The extracted antibiotics from spots were measured by UV spectrophotometry The maximum absorbance of antibiotic extracted from Paenibacillus spp. was 200 nm and Rf = 0.42 which belong to Tetracycline group , while the extracted antibiotic from the second strain which belong to the species and gave Rf = 0.87 and maximum absorbance at 200nm so ,which indicate this antibiotic belong to the β-Lactams also the antibiotic extracted from the strain belong to Bacillus mycoides developed Rf = 0.63 and 200nm which appearance this antibiotic belong to β-Lactams group. The presence more than one spots on TLC plate may indicate that the bacteria had produced other secondary metabolites or the antibiotic is broad spectrum and produced more than one antibiotic. Strains which belong to species Thermoactinomyces intermedius and Thermoactinomyces vulgaris had a weak effect against the bacteria under the study.
