Oil release with amino acid-based compounds having a long chain N-acyl group

A method for improving oil recovery from an oil-coated surface comprising:

• a) providing an aqueous composition comprising at least one compound of the structure:
• where:
• R1 is H, CH3, or is part of a heterocyclic ring (—CH2—)n, where n=3, 4, or 5 and the ring is directly connected to the rest of the structure at R4;
• R2 is an alkyl group (—CH2—)n where n=0 or 1;
• or (—CHCH3—)n, where n=1;
• R3 and R4 are independently H, a straight chain alkyl or branched-chain alkyl group with 1 to 5 carbons, —CH2OH, —CH2CH2SCH3, a cycloalkyl group, a substituted cycloalkyl group, an aryl group, an alkylaryl group;
• a substituted aryl group;
• a phenyl group, —CH2Ph (Ph is phenyl), —CH(Ph)Ph;
• a heterocycle;
• a substituted heterocycle;
• or is part of a heterocyclic ring (—CH2—)n, where n=3, 4, or 5 and is directly connected to the rest of the structure at R1;
• R5 is a monovalent cation or H;
• and
• R6 is a saturated alkyl chain —(CH2)nCH3, where n is equal to or between the integers of 11 and 22, or R6 is a monounsaturated alkyl chain or polyunsaturated alkyl chain containing the number of carbons equal to or between the integers of 11 and 23 and containing 1, 2 or 3 units of unsaturation;
• and
• b) providing one or more microorganisms which grow in the presence of oil and an electron acceptor;
• c) providing a minimal growth medium comprising a carbon source and an electron acceptor;
• d) contacting an oil-coated surface with the composition of (c);
• e) releasing the oil from said oil-coated surface to provide a released oil;
• and
• f) recovering the released oil.