Clinical Microbiology: Open Access

Screening methods for detection of biosurfactants produced by bacterial strains with biodegradative capacity

3^rd International Conference on Clinical Microbiology & Microbial Genomics

September 24-26, 2014 Valencia Convention Centre, Spain

Robertina Ionescu, Ana-Maria Tanase, Iulia Chiciudean, Diana Pelinescu, Ionela Sarbu, Ortansa Csutak, Tatiana Vassu and Ileana Stoica

Posters: Clin Microbial

Abstract:

Due to the many advantages of biosurfactants compared with synthetic surfactants, like biodegradability, lower toxicity, higher stability at different pH and temperature, this type of compounds have drawn considerable attention in recent years, especially for their efficiency in bioremediation processes. The main goal of our study was to test and select biodegrading bacterial strains with high ability to produce biosurfactants. Our studies included 45 bacterial strains isolated from various polluted sites (soil samples contaminated with petroleum, kerosene, quinoline) and previously identified as belonging to the genera Pseudomonas, Burkholderia, Acinetobacter, Rhodococcus and, respectively, Flavobacterium. Several optimized screening methods, like methylene blue agar test, emulsifying activities assay (E24), hemolysis test, drop-collapse method and oil spreading test, were used to analyse biosynthesis of biosurfactants. Further on, eleven selected Pseudomonas aeruginosa strains producing biosurfactants were tested to quantify rhamnolipids production on various carbon and nitrogen sources growth media. Production of rhamnolipids in bacterial strains selected was confirmed at molecular level, based on the analysis of rhlB gene, involved in the biosynthesis of such biosurfactants. Finally, a P. aeruginosa strain proved to be most valuable for future biotechnological and environmental applications.

Biography :

Robertina Ionescu is Postdoc Researcher in the Department of Genetics, Faculty of Biology University of Bucharest, Romania. Her main research interests have focused on microbial biodiversity studies in various ecosystems, biochemical and genetic analyses of microorganisms with biotechnological capabilities, and biologically active compounds biosynthesis (biosurfactants) in microorganisms with biodegradative abilities. She has published more than 15 papers published in well known international journals.