Optical resolution of racemic pantoic acid through microbial stereoselective lactonization in an organic solvent/water two-phase system
1996; Elsevier BV; Volume: 19; Issue: 4 Linguagem: Inglês
10.1016/0141-0229(95)00250-2
ISSN1879-0909
AutoresMichihiko Kataoka, Masao Hirakata, Keiji Sakamoto, Hideaki Yamada, Sakayu Shimizu,
Tópico(s)Microbial Metabolic Engineering and Bioproduction
ResumoThe lactonohydrolase-catalyzed stereospecific lactonization of d-pantoic acid (d-PA) to d-pantoyl lactone (d-PL) was shown to be a promising reaction for the optical resolution of racemic PA. When 385 mm dl-PA was incubated with washed cells of Fusarium oxysporum AKU 3702 showing high lactonohydrolase activity at 30°C for 14 h at pH 4.5–5, 40% of the PA was lactonized with an enantioselectivity of 83% ee for the d-isomer. In an organic solvent-water two-phase system in which an aqueous solution of 1,540 mm dl-PA (200 mg ml−1 as dl-PL) containing 50 mm CaCl2 and cells was incubated with ethyl acetate at 30°C for 20 h at pH 4.5–5, d-PA in the racemic mixture was almost stoichiometrically lactonized to d-PL (90% ee). This improvement was suggested to be due to a shift of the reaction equilibrium during the lactonization on extraction of the reaction product, i.e., d-PL into the organic phase.
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