Journal of Molecular Catalysis B: Enzymatic 14 (2001) 125–129 Enantioselective hydrolysis of epoxides: the employment of the soluble fraction from Vicia sativa seedlings Cinzia Chiappe ∗ , Antonietta De Rubertis, Franco Marioni, Filippo Pelagotti Dipartimento di Chimica Bioorganica e Biofarmacia, via Bonanno 33, 56126 Pisa, Italy Received 20 July 2000; accepted 24 November 2000 Abstract Biocatalytic hydrolysis of meso and racemic aryl- and alkyl-oxiranes was accomplished by employing the epoxide hydrolase activity of the soluble fraction of Vicia sativa seedlings. Whereas meso epoxides were not hydrolyzed by this fraction, racemic compounds were transformed into the corresponding diols by formal anti-stereoselective water attack. Both substrate and product enantioselectivity were strongly influenced by the chains length and the presence of a hydroxyl group. © 2001 Elsevier Science B.V. All rights reserved. Keywords: Epoxide hydrolase; Plant; Asymmetric hydrolysis 1. Introduction Enantiomerically pure epoxides and chiral diols are important building blocks in organic synthesis and can be used as key intermediates in the synthesis of more complex enantiopure compounds. Several chemical and biological production methods have been reported [1–3]. Among several types of enzymes employed, epoxide hydrolases (EHs) are particularly attractive being very efficient biocatalysts for achieving the resolution of racemic epoxides. Chiral epoxides and vicinal diols can be obtained by formal water addition onto the epoxide ring with good to excellent enan- tiomeric purity. Since these enzymes are essentially involved in human detoxification processes, EHs of mammalians origin have been mostly studied up to the recent years [4–6]. In the last years, however, EH activities have been found in organism as diverse as bacteria [7], fungi [8], yeasts [9], insects [10], and ∗ Corresponding author. Tel.: +39-50-44074; fax: +39-50-43321. E-mail address: cinziac@farm.unipi.it (C. Chiappe). plants [11] showing that these enzymes are probably ubiquitous in nature. The possibility to have EHs from different sources, which may be characterized by a different substrate and/or product enantioselectivity have much increased the interest in this kind of biocat- alyst. Thus, the study of the properties of the different EHs, i.e. their molecular mechanism, catalytic behav- ior, substrate and product stereoselectivity is now a topic of relevant importance. EHs exist predominantly in two different forms: a microsomal (mEH) and a cytosolic or soluble (sEH). Both forms hydrolyze a large number of different substrates, in agreement with the detoxifying function. A large number of stud- ies have been carried to characterize these enzymes in mammals, but only few data have been reported on plant EHs. A soluble EH from soybean has been purified and characterized using 9,10-epoxystearic acid as a substrate [12], more recently, soluble EHs were cloned from potato (Solanum tuberosus) [13] and Arabidopsis thaliana [14] and epoxide hydro- lase activity has been found in the microsomal and soluble fraction from Vicia sativa seedlings using 1381-1177/01/$ – see front matter © 2001 Elsevier Science B.V. All rights reserved. PII:S1381-1177(00)00245-9