Author/Authors :
Al-mofraji, Talib K. Al-Muslansirya University, Basic Science Branch - Dentistry College, Iraq , al-kubaisi, sanaa, s.k. University of Baghdad - College of Science - Department of Biology, Iraq
Abstract :
The effects of some chemicals (50 ppm of aniline, phenol, benzoic acid,different concentrations of NaCl, and different pH-values) on growth of two Azotobacter chroococcum strains, wild-type-3, and it s Mutant-44 were studied. The results indicated that the presence of phenol and aniline caused significant increase of growth of the Mutant-44 compared with that in the control. Increase of growth of this mutant in the presence of benzoic acid was observed, whereas, growth of the Wild-type-3 has increase only in the presence of phenol but lower than the control. The Wild-type-3 tolerated NaCl concentrations up to 1.5%, while, growth of the Mutant-44 was inhibited at all NaCl concentrations. Maximum growth of the Wild-type-3 and the Mutant-44 was observed at pH 7 and 9 respectively. Growth of these two tested strains was completely inhibited at highly-acidic and basic conditions
