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The major accruing market for biosurfactants is currently the petroleum industry, which offers different applications for them (Santos et al. 2016).

Petroleum, also known as crude oil is a natural energy source found beneath the earth´s surface. It is a resource that is in great demand, and has become the leading raw material for development and the economy in the past century. It basically consists of two to three phases (liquid/solid and gas), the industry uses several mechanisms to separate these (Almeida et al. 2016). Biosurfactants have shown promising applications in this industry, such as extraction, transportation or petrochemical manufacturing (Makkar et al. 2011).

Approximately 50–65% of oil residues are found in porous rocks, caused by high forces of capillarity, interfacial tension between the aqueous and the hydrocarbon phases and the high viscosity of the crude oil. These residues can often not be recovered by conventional oil recovery methods (Almeida et al. 2016; Santos et al. 2016). Biosurfactants can lower the interfacial tension between oil/rock and oil/water interfaces, in that way the oil-recovery can be enhanced. A mixture containing the producing microorganism can be injected into the porous rock, which will be sealed for a certain time to allow microbial growth. Therefore, the production of biosurfactants allows the breakdown of the oil film in the rocks and oil flow can be re-established. Experiments have shown that the use of indigenous microorganisms Arthobacter sp, Pseudomonas sp and Bacillus sp resulted in a reduction of paraffin from 29.8 to 25.5 % in 9 months (Bachmann et al. 2014).

Because of their amphipilic structure, biosurfactants have highly emulsifying properties which are important for the extraction of oil, to form stable water–oil emulsions (Bachmann et al. 2014).