Production of biosurfactants from agro-industrial wastes

Biosurfactants are surface active compounds produced by microorganisms by growth on various substrates, including renewable resources such as vegetable oil, distillery and dairy wastes. Biosurfactants are attracting attention in recent years because they offer several advantages over chemical surfactants such as low toxicity, inherent good biodegradability and ecological acceptability. The majority of known biosurfactants are synthesized by microorganisms grown on water immiscible hydrocarbons, but some have been produced on such water- soluble substrates as glucose, glycerol and ethanol. Chemically-synthesized surfactants have been used in the oil industry to aid clean up of oil spills, as well as to enhance oil recovery from oil reservoirs. They are extensively used in industry as antifoaming agents. Challenges for production of biosurfactant production is the economic feasibility due to high production cost. This has been a limiting factor in the utility of several prospective biosurfactants. Material selection of raw materials particularly when working with bulk product market, greatly influences production cost. The amount to be used, form (solid or liquid), packaging, transportation purity all affect cost. Specifically, the carbon source is a major constituent of medium .A wide variety has been used, including, hydrocarbons, carbohydrates, and vegetable oil sources. Microorganisms use several substrates, together or independently. This review puts together materials like agro-industrial wastes that have successfully been used for biosurfactant production so as to facilitate technology development in this field.