en Related Fields Related Fields مقاله کامل Full Length/Original Article <p><strong>Background</strong>: A glycolipopeptide biosurfactant produced by <em>Pseudomonas aeruginosa</em> strain IKW1 reduced the surface tension of fermentation broth from 71.31 to 24.62 dynes/cm at a critical micelle concentration of 20.80 mg/L. The compound proved suitable for applications in emulsion stabilization in food, as well as in cosmetic and pharmaceutical formulations. <strong>Methods</strong>: In the present study, Plackett-Burman design (PBD) and response surface method (RSM) were employed to screen and optimize concentrations of trace nutrients in the fermentation medium, to increase surfactant yield. <strong>Results</strong>: The PBD selected 5 out of the 12 screened significant trace nutrients. The RSM, on the other hand, resulted in the production of 84.44 g glycolipopeptide/L in the optimized medium containing 1.25 mg/L nickel, 0.125 mg/L zinc, 0.075 mg/L iron, 0.0104 mg/L boron, and 0.025 mg/L copper. <strong>Conclusion</strong>: Significant second-order quadratic models for biomass (<em>P</em><0.05; adjusted <em>R</em>²=94.29%) and biosurfactant (<em>R</em>²=99.44%) responses suggest excellent goodness-of-fit of the models. However, their respective non-significant lack-of-fit (Biomass: <em>F</em>=1.28; <em>P</em>=0.418; Biosurfactant: <em>F</em>=1.20; <em>P</em>=0.446) test results indicate their adequacy to explain data variations in the experimental region. The glycolipopeptide is recommended for the formulation of inexpensive pharmaceutical products that require surface-active compounds</p> Pseudomonas aeruginosa, Surface-active agents, Fermentation, Nickel, Copper 249 260 http://ibj.pasteur.ac.ir/browse.php?a_code=A-10-1-656&slc_lang=en&sid=1 Maurice George Ekpenyong maurygg2002@unical.edu.ng Yes Environmental Microbiology and Biotechnology Unit, Department of Microbiology, Faculty of Biological Sciences, University of Calabar, P.M.B.1115 Calabar, Nigeria Sylvester Peter Antai No Environmental Microbiology and Biotechnology Unit, Department of Microbiology, Faculty of Biological Sciences, University of Calabar, P.M.B.1115 Calabar, Nigeria Atim David Asitok No Environmental Microbiology and Biotechnology Unit, Department of Microbiology, Faculty of Biological Sciences, University of Calabar, P.M.B.1115 Calabar, Nigeria Bassey Offiong Ekpo No Exploration, Research and Services Section, Research and Development (R&D) Division, Nigerian National Petroleum Corporation (NNPC), Port-Harcourt, Nigeria