Optimization of the asymmetric synthesis of (S)-1-phenylethanol using Ispir bean as whole-cell biocatalyst

Abstract

In this study, enantiomerically pure (S)-1-phenylethanol was produced via asymmetric bioreduction of acetophenone. Ispir bean (Phaseolus vulgaris) was used as an alcohol dehydrogenase (ADH) source since whole cells are cheaper than isolated enzymes. Acetone powder methodology was applied for biocatalyst. Glucose was used as a cosubstrate in-order to regenerate cofactor (NADPH). The reactions were carried out in an orbital shaker whose temperature and agitation rate can be controlled. (S)-1-phenylethanol concentration was analyzed by HPLC using a Chiralcel OB column. Effects of the reaction time, substrate concentration, cosubstrate concentration and biocatalyst concentration on the (S)-1-phenylethanol production were investigated using Response Surface Methodology (RSM). 36 h bioreduction time, 6 mM acetophenone concentration, 25.15 mM glucose concentration, and 175 mg/mL biocatalyst concentration were determined as optimum values. In these conditions, 2.4 mM (S)-1-phenylethanol was obtained in phosphate buffer (pH=7.0) at 30°C with >99% enantiomeric excess.

A functionalized Hf(iv)–organic framework introducing an efficient, recyclable, and size-selective heterogeneous catalyst for MPV reduction

“…Chiral alcohols are essential preliminary resources for the synthesis of several modern pharmaceuticals and agrochemicals. 1 In particular, ( R )- and ( S )-phenyl ethanol are useful building blocks for the synthesis of complex molecules and are stunning compounds for a widespread series of potential applications in the drug industry. 2 These compounds can be produced by the catalytic transfer hydrogenation (CTH) of carbonyls.…”

Lipase Immobilized on MCFs as Biocatalysts for Kinetic and Dynamic Kinetic Resolution of sec-Alcohols

“…One of the important group of compounds are chiral sec-alcohols, and, in particular, chiral 1-phenylethanol, which is used as an ophthalmic preservative, a solvatochromic dye, an inhibitor of cholesterol absorption, as a mild floral fragrance and as precursor material for the synthesis of enantiomerically pure active pharmaceutical ingredients [2][3][4]. Consequently, various methods for its preparation have been developed: chromatographic separation using porous coordination polymers, asymmetric bioconversion of acetophenone using whole cells, direct hydrogenation of acetophenone using Ru based Noyori catalyst, chemo-and biocatalytic stereoselective reduction from pro-chiral ketones, or enantioselective resolution of racemates [5][6][7][8][9][10][11][12]. Among several production routes, kinetic resolution (KR), and more recently, its dynamic kinetic mode (DKR) appears to be the most effective, and, thus, widely studied method.…”