Australian Journal of Basic and Applied Sciences, 4(8): 3484-3498, 2010 ISSN 1991-8178 Structural Analysis and Characteristics of Biosurfactants Produced by Some Crude Oil Utilizing Bacterial Strains Bayoumi, R.A., Haroun, B.M.,Ghazal, E.A. and Maher, Y.A. Botany and Microbiology Dept., Faculty of Science (Boys), Al-Azhar Univ. Cairo, Egypt, P.N.11884 Abstract: Biosurfactants or surface active compounds (SACs) are produced by certain microorganisms. Twenty seven bacterial isolates were isolated from twenty four crude oil contaminated soils located in repairing cars stations and petroleum refining companies. Three bacterial isolates were selected and displayed highest reduction of surface tension. Three selected bacterial isolates were identified as Paenibacillus illinoisensis-21, Bacillus subtilis-27 and Bordetella hinizi-DAFI. Maximum SACs biosynthesis by Paenibacillus illinoisensis-21, Bacillus subtilis-27 and Bordetella hinizi-DAFI strains were investigated. Two SACs could be biosynthesized from B. subtilis-27 and Bordetella hinizi-DAFI, which could be extracted by chloroform: ethanol (2:1v/v) solvent and purified by using TLC and Silica gel chromatography. The SACs were identified as Iturin which biosynthesized by B. subtilis-27 and Trehalose-2,3,4,2'-tetraester which biosynthesized by Bordetella hinizi-DAFI based on UV, IR and HPLC analysis techniques. Detection the qualitative and quantitative of amino acids were performed by amino acids analyzer, -1 H-Nuclear Magnetic Resonance (NMR) analysis, fatty acid analysis and sugar pattern. Key words: Biosurfactants, Paenibacillus, Bacillus subtilis and Bordetella, Iturin,Surfactin. INTRODUCTION One of the important properties of hydrocarbon degrading bacteria is the production of surface active agents (biosurfactants) can be applied to soils contaminated with petroleum hydrocarbons to enhance bioremediation (Banat, I.M., 1995; Banat, I.M., 1991;Batista, S.B., 2006; Bodour, A.A., 2003). Surface active compounds produced by microorganisms are divided into two main types. These that reduce surface tension at air-water interface (biosurfactants) and those that reduce the interficial tension between immiscible liquids, or at the solid-liquid interfaces (bioemulsifires). Biosurfactants are amphipathic compounds excreted by microorganisms that exhibit surface activity (Nitschke, M. and G.M. Pastore, 2006). There are many complex molecules included in biosurfactants, e.g. glycolipids, lipopeptides, fatty acids, polysaccharide- protein complexes, peptides, phospholipids and neutral lipids. Biosurfactants have advantages over their chemical counterparts in biodegradability, low toxicity, higher biodegradability, better environmental compatability, high selectivity, specific activity at extreme temperature, pH, salinity and the ability to be synthesized from renewable feedstock (Thanomsub, B., 2006). Because of these properties ,biosurfactants have a variety of potential applications, including in pharmaceutical, cosmetic, detergent and food industry. In addition, biosurfactants also play an important role in the bioremediation of organic pollutants. Therefore, biosurfactants have received more and more attention in recent years. During the process of crude petroleum biodegradation , petroleum –degrading strains utilize petroleum hydrocarbons as sole source of carbon and energy. Many environmental factors , such as pH, temperature, salinity, type of nutrients, etc., cab influence the physicochemical properties of a microbial biosurfactants (Banat, I.M., 1991;Batista, S.B., 2006; Bodour, A.A., 2003). The aim of the present study was to optimize conditions for three biosurfactants production by three most potent crude oil utilizing bacterial isolates. Extraction, purification and characterization of the two biosurfactants also discussed. Corresponding Author: Bayoumi, R.A., Botany and Microbiology Dept., Faculty of Science (Boys), Al-Azhar Univ. Cairo, Egypt, P.N.11884 3484