@article{Motwali_Aly_Qari_Alhazmi_2021, title={Effect of nutritional factors and growth conditions on biosurfactant production by Pseudomonas mendocina and Pseudomonas oleovorans isolated from oil contaminated soil in Jeddah city}, volume={7}, url={https://jocms.org/index.php/jcms/article/view/1133}, DOI={10.22317/jcms.v7i6.1133}, abstractNote={<p><strong>Objectives:</strong> The current study aimed to investigate the impact of different nutritional factors and growth conditions on biosurfactant production by bacterial isolates (EMB16 and EMB21) isolated from oil-contaminated soil samples.</p> <p><strong>Methods:</strong> Based on the used quantitative and qualitative screening method in current study, the selected bacterial isolates showed a high potential to produce biosurfactant. <strong>Results:</strong> By using 16S rRNA sequence analysis, the bacterial isolates EMB16 and EMB21 were found to be closely related to <em>Pseudomonas mendocina</em> and <em>Pseudomonas oleovorans</em>, respectively. The ultimate yields of biosurfactant (8.06±0.06 mg/ml) by <em>Ps. mendocina</em> EMB16 was with corn oil as a carbon source, urea as a nitrogen source, C/N ratio of 30, pH value of 7, and 2% inoculum size. For <em>Ps. oleovorans</em> EMB21, the maximum biosurfactant production (4.68±0.14mg/ml) was achieved by diesel oil as a carbon source, urea as a nitrogen source, C/N ratio of 30, pH of 7, and 5% size of inoculum. The best incubation period and temperature for the examined strains was 168 hrs. at 37℃.</p> <p><strong>C</strong><strong>onclusion:</strong> The results proved that <em>Ps. mendocina</em> EMB16 was the most efficient biosurfactant producer as it showed the greatest amount of biosurfactant concentration and lowestvalue of surface tension measurement with an emulsification index of 67±6%.</p>}, number={6}, journal={Journal of Contemporary Medical Sciences}, author={Motwali, Ebtihal A. and Aly, Magda M. and Qari, Huda A. and Alhazmi, Nuha M.}, year={2021}, month={Dec.} }