CULTURES POTENTIALITY OF PSEUDOMONAS AERUGINOSA FOR THE BIOSURFACTANT PRODUCTION

Abstract

This work has as main objective to investigate the production of biosurfactant by strain of Pseudomonas aeruginosa, an originating from culture collection (ATCC 9027) and another isolated from a hydrocarbon contamined soil (PALC). To evaluate the results of the experiments a factorial experimental design was used, studying as variables the concentrations of residual soybean oil from several foods frying, nitrate of ammonium and brewery residual yeast. The experiments were performed in 500-mL Erlenmeyer flasks containing 50 mL of production medium, maintained in the rotary shaker, at 170 rpm and 30 ± 1°C, for a 48-h fermentation period. Biosurfactant production has been monitored by measurements of rhamnose concentration, surface tension and emulsifying activity. The strain Pseudomonas aeruginosa ATCC 9027 and Pseudomonas aeruginosa isolated were capable to reduce the superficial tension of the initial medium of 61± 1 dynes/cm for 26,0 dynes/cm and 28,0 dynes/cm, to produce rhamnose in the concentration of 1,39 and 0,59 g/L with emulsification index of 100%, respectively. After recuperation and purification of the biosurfactant the rhamnose concentration increased in 80% in the final product. Keywords: Pseudomonas aeruginosa, biosurfactant, soybean oil, surface tension.