structures a fifth class of msls include those modified at the sophorose 6 u2032 or 6 u2033 positions by inter alia an activated acyl molecule such as the vinyl ester or alkyl ester of propionic acid catalyzed by an enzyme catalyst such as a lipase in conjunction with one or more of the modifications described herein in one exemplary reaction bisht et al 1999 the unsubstituted open chain acidic sophorolipid is acetylated at the sophorose 6 u2032 hydroxyl position it is contemplated that carbonyl compounds of varying chain lengths and degrees of branching can be incorporated and that a variety of carbonyl containing functional groups can be incorporated including succinate malate and citrate additionally it is contemplated that esters of amino acids and oligopeptides can be incorporated at the 6 u2032 and or 6 u2033 positions of the sophorose ring finally it is contemplated that the 6 u2032 and or 6 u2033 positions of the sophorose ring may be alkylated fig1 by ethylene oxide or a substituted alkylene oxide such as 2 3 epoxypropyl 1 1 1 trimethylammonium chloride quab151 or related electrophiles as described by solarek 1989 such substitutions will likely occur at the primary 1 u00b0 6 u2032 and or 6 u2033 positions but may also occur at the secondary 2 u00b0 sophorose ring hydroxyl groups to generate mixtures of sophorolipid derivatives.