Rhamnolipid biosurfactant production by Pseudomonas aeruginosa MR01 using vegetable oil refinery wastes

Aim and Biosurfactants are a group of secondary metabolites with surface active properties like reducing superficial and interfacial tensions that are synthesized by a variety of micro-organisms. Interest in their potential applications by various industries has significantly increased recently, particularly because of their advantages such as lower toxicity, biodegradability and effectiveness at a wide range of pH and temperature values. Use of expensive substrates is among several economic limitations for large scale production of biosurfactants. A suggested strategy to solve this cost problem is the use of inexpensive substrates such as lipidic wastes. This research aimed to evaluate the vegetable oil refinery wastes as inducing substrates for rhamnolipid biosynthesis by Pseudomonas aeruginosa MR01, and their transformation to high value-added materials. In this research, fatty acids present in vegetable oil refinery wastes and total organic materials were measured using Gas-Chromatography and COD, respectively. Biosurfactant emulsification was determined through the emulsification index (E24). COD for oil wastes showed high values around 2,000,000 and emulsification was obtained on average about 40%. A dramatic emulsification activity of rhamnolipid biosurfactants produced by high COD oil wastes represented a promising green material to reduce the problems regarding the wastes and hydrophobic pollutants accumulation.