Estudo da produção de metabólitos por Pseudomonas aeruginosa: Ramnolipídios e Polihidroxialcanoatos (PHAs))

Abstract

This work evaluated the rhamnolipid and PHAs production by Pseudomonas sp. in alternative low-cost substrates from food processing, determining the properties, applications and chemistry composition of compounds obtained. Were isolated 21 strains, being that 2 isolates were able to growth and produce rhamnolipids and PHAs in the substrates. These bacteria were identified as Pseudomonas aeruginosa. The polymers and surfactants produced were characterized by gas-chromatography mass spectrophotometry (GC-MS) and by high performance liquid chromatography-MS (HPLC-MS), and their composition was found to vary with the carbon source and the strain used in the fermentation. The best overall production of rhamnolipids and PHAs was obtained with cassava wastewater added with waste cooking oil (CWO) as the carbon source, with PHA production corresponding to 39% of the cell dry weight and rhamnolipids production being 660 mg/L. It would appear that CWO has the highest potential as alternative substrate, and its use may contribute to a reduction in the overall environmental impact generated by discarding such residues. The rhamnolipid produced by P. aeruginosa L2-1 in CWO showed excellent tension-active properties (low values of critic micellar concentration and superficial and interfacial tensions) and potential to use in remediation of contaminated environmental, removing 89% of petroleum after washing process in sand, with characteristics similar or better than commercial rhamnolipid JBR599 (Jeneil Biosurfactant Co.)