A Comparative Study on Chemical Characterization and Properties of Surface Active Compounds From Gram-positive Bacillus and Gram-negative Ochrobactrum Strains Utilizing Pure Hydrocarbons and Waste Mineral Lubricating Oils

Abstract

Mineral lubricating oils are widely used in various industrial sectors for their applications in maintenance and functioning of machineries. However, indiscriminate dumping of these used oils has resulted in polluting the natural reservoirs which subsequently destroys ecological balance. Bacteria can emulsify or lower surface tension between phases of immiscible substrates and can acquire them as their carbon and energy sources. Such a phenomenon is mediated by synthesis of extracellular polymeric substances which can function as eminent surface active compounds based on their surfactant or emulsifying nature. The comparison between bacterial strains (Gram-positive Bacillus stratosphericus A15 and Gram-negative Ochrobactrum pseudintermedium C1) on utilisation of pure straight chain hydrocarbons, waste mineral lubricating oils as sole carbon source and chemical characterization of the synthesized surface active compounds is studied. Characterization analysis by Ultraviolet Visible spectrophotometry, Fourier-transform infrared spectroscopy, Nuclear Magnetic Resonance spectroscopy, Carbon-Hydrogen-Nitrogen analysis has given detailed structural elucidation of surface active compounds. The contrasting nature of bacterial strains in utilisation of different hydrocarbons of spindle oil was observed in Gas Chromatography-Mass Spectroscopy. The variation between both strains in utilisation of hydrocarbons can be manifested in a difference in chemical structure and properties of the synthesized surface active compounds. Scanning Electron Microscopy gives detailed insight into the difference in morphological nature of the compounds. The utilisation of these lubricating oils can address waste disposal problem and offer an economical feasible approach for bacterial synthesis of surface active compounds. Additionally, their distinctive nature and properties can maneuver applications in bioremediation of toxic environmental pollutants and as biomaterials in pharmaceutics.