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MeSH: kyseliny mandlové-metabolismus

8 záznamů v PubMed Filtry

Článek

Biocatalytic production of mandelic acid and analogues: a review and comparison with chemical processes

Martínková, Ludmila
Autor Martínková, Ludmila ORCID Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, CZ-142 20, Prague, Czech Republic. martinko@biomed.cas.cz
Křen, Vladimír
Autor Křen, Vladimír Laboratory of Biotransformation, Institute of Microbiology of the Czech Academy of Sciences, Vídeňská 1083, CZ-142 20, Prague, Czech Republic

Applied microbiology and biotechnology. 2018 May ; 102 (9) : 3893-3900. [epub] 20180310

Appl Microbiol Biotechnol
ISSN 1432-0614 | 0175-7598
Zdroj

The aim of this study is to summarize the current progress in the design of biocatalytic processes applicable for the production of optically pure mandelic acids and their analogues. These compounds are used as building blocks for pharmaceutical chemistry and as chiral resolving agents. Their enzymatic syntheses mainly employed nitrile hydrolysis with nitrilases, ester hydrolysis, ammonolysis or esterification with lipases or esterases, and ketone reduction or alcohol oxidation with dehydrogenases. Each of these methods will be characterized in terms of its product concentrations, enantioselectivities, and the types of catalysts used. This review will focus on the dynamic kinetic resolution of mandelonitrile and analogues by nitrilases resulting in the production of high concentrations of (R)-mandelic acid or (R)-2-chloromandelic acid with excellent e.e. Currently, there is no comparable process for (S)-mandelic acids. However, the coupling of the S-selective cyanation of benzaldehyde with the enantioretentive hydrolysis of (S)-mandelonitrile thus obtained is a promising strategy. The major product can be changed from (S)-acid to (S)-amide using nitrilase mutants. The competitiveness of the biocatalytic and chemical processes will be assessed. This review covers the literature published within 2003-2017.

Klíčová slova
Dehydrogenase, Enantioselectivity, Esterase, Lipase, Mandelic acid, Nitrilase,
MeSH
aminohydrolasy genetika metabolismus MeSH
biokatalýza MeSH
kinetika MeSH
kyseliny mandlové metabolismus MeSH
průmyslová mikrobiologie * trendy MeSH
stereoizomerie MeSH
Publikační typ
časopisecké články MeSH
přehledy MeSH
Názvy látek
aminohydrolasy MeSH
kyseliny mandlové MeSH

Článek

Exploring the potential of fungal arylacetonitrilases in mandelic acid synthesis

Molecular biotechnology. 2015 May ; 57 (5) : 466-74.

Mol Biotechnol
ISSN 1559-0305 | 1073-6085
Zdroj

The application of arylacetonitrilases from filamentous fungi to the hydrolysis of high concentrations of (R,S)-mandelonitrile (100-500 mM) was demonstrated for the first time. Escherichia coli strains expressing the corresponding genes were used as whole-cell catalysts. Nitrilases from Aspergillus niger, Neurospora crassa, Nectria haematococca, and Arthroderma benhamiae (enzymes NitAn, NitNc, NitNh, and NitAb, respectively) exhibited different degrees of enantio- and chemoselectivity (amide formation). Their enantio- and chemoselectivity was increased by increasing pH (from 8 to 9-10) and adding 4-10% (v/v) toluene as the cosolvent. NitAn and NitNc were able to convert an up to 500 mM substrate in batch mode. NitAn formed a very low amount of the by-product, amide (<1% of the total product). This enzyme produced up to >70 g/L of (R)-mandelic acid (e.e. 94.5-95.6%) in batch or fed-batch mode. Its volumetric productivities were the highest in batch mode [571 ± 32 g/(L d)] and its catalyst productivities in fed-batch mode (39.9 ± 2.5 g/g of dcw). NitAb hydrolyzed both enantiomers of 100 mM (R,S)-mandelonitrile at pH 5.0 and is therefore promising for the enantioretentive transformation of (S)-mandelonitrile. Sequence analysis suggested that fungal arylacetonitrilases with similar properties (enantioselectivity, chemoselectivity) were clustered together.

MeSH
aminohydrolasy chemie genetika metabolismus MeSH
Arthrodermataceae enzymologie MeSH
Aspergillus niger enzymologie MeSH
druhová specificita MeSH
fungální proteiny chemie genetika metabolismus MeSH
fylogeneze MeSH
koncentrace vodíkových iontů MeSH
kyseliny mandlové metabolismus MeSH
Nectria enzymologie MeSH
Neurospora crassa enzymologie MeSH
Publikační typ
časopisecké články MeSH
práce podpořená grantem MeSH
Názvy látek
aminohydrolasy MeSH
fungální proteiny MeSH
kyseliny mandlové MeSH
mandelic acid MeSH Prohlížeč

Článek

The evidence for conjugated mandelic and phenylglyoxylic acids in the urine of rats dosed with styrene

Toxicology letters. 1997 Feb 07 ; 90 (2-3) : 199-205.

Toxicol Lett
ISSN 0378-4274
Zdroj

Male Wistar rats were dosed intraperitoneally with styrene (400 mg/kg). Urine samples were collected over phosphate buffer, pH 6.5 for 24 h. Excretion of mandelic (MA) and phenylglyoxylic acid (PGA) amounted to 1.66 +/- 0.62 and 5.21 +/- 2.44% of dose, respectively, as determined by ion-pair HPLC. After acidic hydrolysis, the amount of MA and PGA found in urine increased to 2.10 +/- 0.84 and 6.81 +/- 3.20% (mean +/- S.D.; n = 7), respectively. A similar increase was observed after alkaline hydrolysis of urine samples. Differences between hydrolysed and non-hydrolysed samples were significant in the paired t-test (P < 0.05). Further, urine samples were fractionated by HPLC. Fractions were subjected to acidic hydrolysis and analysed by HPLC and GC/MS. Both MA and PGA were detected in the fraction which did not contain any of these metabolites before hydrolytic treatment. Thus, MA and PGA, which are used as biomarkers of exposure to styrene, form hydrolysable conjugates in the rat. At least a minor part of the total urinary MA and PGA is bound in these conjugates.

MeSH
biopolymery moč MeSH
glyoxyláty chemie metabolismus moč MeSH
injekce intraperitoneální MeSH
krysa rodu Rattus MeSH
kyseliny mandlové chemie metabolismus moč MeSH
plynová chromatografie s hmotnostně spektrometrickou detekcí MeSH
potkani Wistar MeSH
proteinurie moč MeSH
styren MeSH
styreny farmakokinetika toxicita MeSH
zvířata MeSH
Check Tag
krysa rodu Rattus MeSH
mužské pohlaví MeSH
zvířata MeSH
Publikační typ
časopisecké články MeSH
práce podpořená grantem MeSH
Názvy látek
biopolymery MeSH
glyoxyláty MeSH
kyseliny mandlové MeSH
mandelic acid MeSH Prohlížeč
phenylglyoxylic acid MeSH Prohlížeč
styren MeSH
styreny MeSH

Článek

Penicillinamidohydrolase in Escherichia coli. I. Substrate specificity

Folia microbiologica. 1975 ; 20 (3) : 224-30.

Folia Microbiol (Praha)
ISSN 0015-5632
Zdroj

Substrate specificity of the bacterial penicillinamidohydrolase (penicillinacylase, EC 3.5.1.11) from Escherichia coli was determined by measuring initial rates of enzyme hydrolysis of different substrates within zero order kinetics. Some N-phenylacetyl derivatives of amino acids and amides of phenylacetic acid and phenoxyacetic acid of different substituted amides of these acids or amides, structurally and chemically similar to these compounds, served as substrates. Significant differences in ratios of initial rates of the enzyme hydrolysis of different substrates were found using a toluenized suspension of bacterial cells or a crude enzyme preparation, in spite of the fact that the enzyme is localized between the cell wall and cytoplasmic membrane, in the so-called periplasmic space. N-phenylacetyl derivatives are the most rapidly hydrolyzed substrates. Beta-phenylpropionamide and 4-phenylbutyramide were not utilized as substrates. The substrate specificity of the enzyme is discussed with respect to a possible use of certain colourless compounds as substrates, hydrolysis of which yields chromophor products suitable for a simple and rapid assay of the enzyme activity.