The Enantioselectivity of the biohydrolysis of sec-alkyl sulfate esters using a bacterial alkylsulfatase from Rhodococcus ruber DSM 44541 was dramatically enhanced in presence of additives ('enhancers') such as carbohydrates, polyethylene glycol, detergents, metal ions and through enzyme immobilization. In presence of iron, the E value for the kinetic resolution of (+/-)-3- and (+/-)-4-octyl sulfate was improved from E=3.9 to =<200 and E=1.1 to 10, respectively.