Novel Hydrolases from Thermophilic Filamentous Fungi for Enantiomerically and Enantiotopically Selective Biotransformations

Abstract

Fourteen thermophilic filamentous fungi were cultivated on two shake flask media and the supernatants were assayed for lipase/carboxylesterase activities using olive-oil, p-nitrophenyl palmitate and p-nitrophenyl butyrate as substrates. The crude enzyme powders (acetone precipitated supernatants) were tested as biocatalysts in organic solvents. Kinetic resolution of racemic 1-phenylethanol (rac-1) and desymmetrisation of 2-acyloxypropan-1,3-diols (3a, b) by acetylation with vinyl acetate were chosen for testing the biocatalytic abilities of these preparations. The tested biocatalysts proved to be comparable to the commercially available enzymes with respect to the degree of enantiomer selectivity, whereas they exhibited a wider range of enantiotopic selectivity than the most common commercial enzymes.

Lipase-catalyzed kinetic resolution of 4-aryl- and 4-heteroarylbut-3-en-2-ols

“…These data support the former observations that many preparations of filamentous fungi exhibiting lipase/esterase activity produced by submerged (SmF) 6 or solid state fermentation (SSF) 7 are useful biocatalysts in stereoselective organic reactions. In the kinetic resolution of the allylic alcohol rac-3a, two SSF preparations exhibited better "anti-Kazlauskas" selectivities (E ~ 7, ).…”

“…From our previous screens of thermophilic (SmF) 6 and mesophilic filamentous fungi (SSF), 7 several biocatalysts having comparable lipase activities and enantiomer selectivities to the widely used commercially available lipases were available for further screening.Within the strains of the SSF screen, 7 a preparation (Mucor hiemalis) with the less usual anti-Kazlauskas selectivity was also found. Therefore we could study the kinetic resolution of several less characterized racemic allylic alcohols by a range of commercial and in-house prepared enzymes.…”

“…All further chemicals and solvents were of analytical grade or higher and purchased from Sigma-Aldrich, Hungary Ltd. 1-Benzyl-1H-indole-3-carbaldehyde (1c) was prepared as described previously. BUTE and SSF enzymes were obtained from thermophilic and mesophilic fungi cultivated under submerged 6 and solid state fermentation, 7 respectively. BUTE-3b: Malbranchea pulchella var.…”

“…5 The commercial availability of a range of lipase preparations at low cost has also widely expanded their use as biocatalysts in organic chemistry. Several studies on screening some thermophilic filamentous fungi in submerged fermentation (SmF) conditions, 6 and some poorly studied mesophilic fungi in solid state fermentation (SSF) 7 conditions for lipase/esterase activity resulted in biocatalysts exhibiting high enantiomer selectivity in synthetic biotransformations. The recent study of fungal SSF preparations acting on several typical secondary alcohols − such as 1-phenylethanol, 1-cyclohexylethanol and 1-(napth-2-yl)ethanol − as model substrates indicated that SSF biocatalysts with lipase activity are applicable in kinetic resolutions of racemic secondary alcohols.…”

Lipase-catalyzed kinetic resolution of 2-methylene-substituted cycloalkanols in batch and continuous-flow modes

“…Lipase from porcine pancreas Type II, a-Chymotrypsin from bovine pancreas Type II, and Papain from Carica papaya were obtained from Sigma-Aldrich. Pig liver esterase (PLE), as an acetone powder, and lipase BUTE 3b [28] were prepared in our laboratory. Sol-gel Lipase AK (sol-gel LAK) was prepared from Lipase AK by established methods [29].…”