[Show abstract][Hide abstract] ABSTRACT: Two δ-iodo-γ-lactones and two γ-iodo-δ-lactones substituted at the β-position with phenyl or 4-methylphenyl ring have been synthesized in both enantiomeric forms. The starting materials were enantiomerically enriched allyl alcohols with an (E)-4-phenylbut-3-en-2-ol system (ee in the range 88–99 %), which were obtained by lipase-catalyzed transesterification. Alcohols were subjected to orthoacetate modification of the Claisen rearrangement. The high stereoselectivity of this reaction led to retention of (E)-configuration of the double bond and complete transfer of chirality from the allyl alcohol to the benzylic position C-3. As a result, chiral γ,δ-unsaturated esters with retained configuration of the stereogenic center were produced. Their hydrolysis and iodolactonization afforded new enantiomers of iodolactones with high or excellent ee (97–99 %). Their configuration at C-4 was a direct result of the configuration at C-3 of the acid subjected to iodolactonization, whereas stereocenters at C-5 and C-6 were formed as a consequence of the reaction mechanism. For most of the synthesized isomers, the predicted configurations were established by X-ray analysis. The presented chemoenzymatic pathway represents a useful strategy that can be applied in the asymmetric synthesis of variety of lactones from 4-arylbut-3-en-2-ols.
Annalen der Chemie und Pharmacie 12/2014; · 3.15 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Środki słodzące są nieodłącznym składnikiem żywności, począwszy od octanu ołowiu poprzez sacharozę, a skończywszy na szeregu nowych związków
o właściwościach słodzących. Spośród nich na szczególną uwagę zasługuje dihydrochalkon neohesperydyny, związek charakteryzujący się m.in. dużą intensywnością słodyczy, niską kalorycznością oraz niepowodujący próchnicy zębów.
Wplyw Młodych Naukowców na Osiągnięcia Polskiej Nauki; 01/2014
[Show abstract][Hide abstract] ABSTRACT: Biotransformations of two substrates: chalcone (1) and 2′-hydroxychalcone (4) were carried out using four yeast strains and five filamentous fungi cultures. Substrate 1 was effectively hydrogenated in all of tested yeast cultures (80–99% of substrate conversion after 1 h of biotransformation) affording dihydrochalcone 2. In the cultures of filamentous fungi the reaction was much slower, however, Chaetomium sp. gave product 2 in 97% yield. After 12 h of incubation a reduction of dihydrochalcone 2 to alcohol 3 was additionally observed. After 3 days of biotransformation in the culture of Rhodotorula rubra product (S)-3 was obtained with 75% ee (enantiomeric excess) and 99% of conversion. Also after a 3-day biotransformation using the strain Fusarium culmorum product (R)-3 was obtained with 98% ee and 97% of conversion. In most of the tested strains a change in enantiomeric excess of compound 3 during the biotransformation process was noticed. In the culture of Rhodotorula glutinis after 3 h of transformation alcohol (R)-3 was formed with 47% ee and 31% of substrate conversion, whereas after 6 days the (S)-3 enantiomer was obtained with 99% ee and 91% of conversion. In the case of 2′-hydroxychalcone (4), the hydrogenation proceeded much slower and led to 2′-hydroxydihydrochalcone (5) – in the culture of Yarrowia lipolytica 97% of conversion was observed after 3 days. In all cultures of the tested strains no products of 2′-hydroxydihydrochalcone reduction were detected.
Journal of Molecular Catalysis B Enzymatic 12/2013; 98:55–61. · 2.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A convenient pathway for the synthesis of new of β-aryl-δ-iodo-γ-lactones is described. The synthetic route led to both cis and trans isomers which were separated by column chromatography or crystallization. The structures of synthesized compounds were confirmed by spectroscopic methods: IR, NMR and HR-MS. For lactones with naphthyl ring (6e and 7e) the crystal structures were also obtained. The lactones were screened for biological evaluation against cancer line HL-60 (human promyelocytic leukemia). The tests showed that the presence of substituent at the benzene ring does not significantly affect the antiproliferative activity of the compound.
Journal of Molecular Structure 09/2013; 1047:160–168. · 1.60 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: In our previous studies bicyclic γ-lactones with cyclohexane ring exhibited high antifeedant activity against storage pests. The activity was correlated with to the type and number of substituents in the cyclohexane ring. One of the most potent group of antifeedant agents was δ-iodo-γ-lactones. RESULTS: We present the synthesis of new bicyclic γ-lactones with the cyclohexane ring containing different halogen atoms. To determine the impact of halogen type on biological activity the lactone without halogen atom was also synthesized. The lactones were tested for their antifeedant activity toward the granary weevil beetle (Sitophilus granarius L.), the khapra beetle (Trogoderma granarium Everts) and the confused flour beetle (Tribolium confusum Du Val.). The results of the tests proved that the highest activity was observed for chlorolactone (7) towards larvae and adults of Tribolium confusum. Antibacterial activity of new lactones was also evaluated. Lactone without halogen atom (8) was active against Staphylococcus aureus and Listeria monocytogenes. CONCLUSIONS: Studies on the biological activity of synthesized lactones revealed high selectivity towards insect pests as well as bacterial strains. Only the halolactones exhibited significant antifeedant activity. In contrary the antibacterial activity was shown only by the lactone (8) without halogen.
Pest Management Science 05/2013; · 2.74 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Simple and fast method of positional analysis of fatty acid composition of phosphatidylcholine (PC) from egg-yolk and soy has been elaborated. The key step of the procedure was complete ethanolysis of PC catalyzed by sn-1,3 specific lipase from Mucor miehei (Lipozyme). 2-Acyl-lysophosphatidylcholine (2-acyl LPC), fatty acids ethyl esters (FAEEs) and free fatty acids (FAs) were formed in this process. No acyl migration was observed during the reaction. The products were entirely separated from the products mixture by simple extraction in water:hexane (2:3v/v) system. The hexane fraction containing free FAs and FAEEs was treated with BF(3)/Et(2)O in ethanol to obtain only FAEEs. The analysis of FAEEs by GC gave the composition of the FAs in the sn-1 position of the PC. 2-Acyl LPC from water fraction after precipitation in cold (-20°C) acetone was converted into FAEEs and analyzed by gas chromatography (GC) to determine FAs composition in the sn-2 position of the PC.
[Show abstract][Hide abstract] ABSTRACT: Glycerol is a by-product generated in large amounts during the production of biofuels. This study presents an alternative means of crude glycerol valorization through the production of erythritol and mannitol. In a shake-flasks experiment in a buffered medium, nine Yarrowia lipolytica strains were examined for polyols production. Three strains (A UV'1, A-15 and Wratislavia K1) were selected as promising producers of erythritol or/and mannitol and used in bioreactor batch cultures and fed-batch mode. Pure and biodiesel-derived crude glycerol media both supplemented (to 2.5 and 3.25 %) and not-supplemented with NaCl were applied. The best results for erythritol biosynthesis were achieved in medium with crude glycerol supplemented with 2.5 % NaCl. Wratislavia K1 strain produced up to 80.0 g l⁻¹ erythritol with 0.49 g g⁻¹ yield and productivity of 1.0 g l⁻¹ h⁻¹. Erythritol biosynthesis by A UV'1 and A-15 strains was accompanied by the simultaneous production of mannitol (up to 27.6 g l⁻¹). Extracellular as well as intracellular erythritol and mannitol ratios depended on the glycerol used and the presence of NaCl in the medium. The results from this study indicate that NaCl addition to the medium improves erythritol biosynthesis, and simultaneously inhibits mannitol formation.
Journal of Industrial Microbiology 05/2012; 39(9):1333-43. · 1.80 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: An assay for quantitative analysis of phosphatidylcholine (1,2-dipalmitoyl-sn-glycero-3-phosphocholine) and its hydrolysis products: 1-hydroxy-2-palmitoyl-sn-glycero-3-phosphocholine and 1-palmitoyl-2-hydroxy-sn-glycero-3-phosphocholine, sn-glycero-3-phosphocholine and palmitic acid using high-performance liquid chromatography with charge aerosol detector (CAD) was developed. The separation of the compounds of interest was achieved on a reversed-phase/hydrophilic interaction stationary phase with a mobile phase consisting of acetonitrile:methanol:10mM ammonium acetate solution. The method was applied to control the acyl migration process of LPC regioisomers in the most common solvents used in the synthesis or modification of PC.
[Show abstract][Hide abstract] ABSTRACT: The phospholipid (PL) fraction from egg yolk was isolated and purified. In the procedure applied (method 2) the egg yolk was
extracted with ethanol, precipitated using acetone chilled to −20 °C and washed using acetone. The purity of the samples was
checked by HPLC analysis using a Charged Aerosol Detector (CAD). The results were compared with those obtained for the phospholipid
fraction isolated and purified by deoiling yolk before extraction and the precipitation of PL with acetone chilled to 4 °C
(method 1). The use of acetone chilled to −20 °C to precipitate and wash the phospholipids yielded the phospholipid fraction
with 100% purity (78.7 ± 0.2 of phosphatidylcholine and 21.3 ± 0.2 of phosphatidylethanolamine). When deoiling and the 4 °C
purification process was used (method 1) 0.4 ± 0.1% cholesterol and some traces of triacylglycerols remained in the PL fraction.
[Show abstract][Hide abstract] ABSTRACT: The effect of feed supplementation with humic-fat preparations on the fatty acid composition of egg yolk phospholipid fractions was studied. The Lohmann Brown was the experimental hen strain and two feeding mixtures were applied – the standard feed and the mixture supplemented with humic-fat preparations. The fatty acid profile of yolk lipids was significantly affected (P = .05) by the supplementation of feed and total increase of n-3 polyunsaturated fatty acids (PUFA) was established. A different distribution of n-3 PUFA in egg yolk lipid fractions was observed: α-linolenic acid (18:3) was found in the triacylglycerol fraction, whereas docosahexaenoic acid (22:6) was detected in the phospholipid fractions. Supplementation of the hen’s diet with humic-fat preparations resulted in the production of n-3 enriched eggs with decreased n-6/n-3 ratio in all phospholipid fractions in comparison to the eggs from the control group.Research highlights► Supplementation of feeds with humic-fat preparations results in the enrichment of eggs with n-3 PUFA. ► The n-6/n-3 ratio can be decreased to the range of 2.3–3.1. ► α-Linolenic acid is deposited in TAG whereas DHA in pure PL fractions (PC and PE). ► PUFA are incorporated in the sn-2 position of glycerol backbone.
[Show abstract][Hide abstract] ABSTRACT: The metabolism of δ-iodo-γ-lactones containing cyclohexane ring with an increasing number of methyl substituents in Absidia cylindrospora was studied and seven metabolites were isolated as the products of biotransformations of these substrates. They were formed as the result of various dehalogenation pathways and four of them (hydroxylactones and epoxylactone) turned out to be new compounds. The conversion of substrates ranged from 60% to 90% and the highest conversion was observed for the iodolactone with an unsubstituted cyclohexane ring. The products were fully characterized by the spectroscopic methods and for the hydroxylactone with gem-dimethyl group at C-5 and hydroxylactone with trimethylcyclohexane system the crystal structures were obtained. The main products formed in the process of hydrolytic dehalogenation were δ-hydroxy-γ-lactones with the hydroxy group located cis in relation to lactone moiety. In case of lactone with 4,4,6-trimethylcyclohexane system the dehydrohalogenation followed by the epoxidation of double bond was also observed. One of the metabolites 4,5-epoxy-2,2,6-trimethyl-9-oxabicyclo[4.3.0]nonan-8-one was formed in the sequence of three reactions: hydroxylation at C-5, translactonization and intramolecular nucleophilic substitution of the iodine by the hydroxy group. Some of the isolated products of transformation of the iodolactone with trimethylcyclohexane system were obtained as the single enantiomers. The application of fungi studied to the dehalogenation of iodolactones could be a useful method in the production of new metabolites with oxygen-containing functional groups with antifeedant activity.
Enzyme and microbial technology. 04/2011; 48(4-5):326-33.
[Show abstract][Hide abstract] ABSTRACT: Teoretyczne wprowadzenie do tematyki kinetycznego i dynamicznego kinetycznego rozdziału oraz przykłady praktycznego zastosowania tego typu procesów do otrzymywania związków o właściwościach zapachowych, antyfidantnych oraz syntonów w produkcji leków.
Wplyw Młodych Naukowców na Osiągnięcia Polskiej Nauki; 01/2011
[Show abstract][Hide abstract] ABSTRACT: Wild strains Fusarium oxysporum and Fusarium avenaceum were chosen among six to the Baeyer–Villiger oxidation of alkylsubstituted cyclohexanones (1a–e) to the corresponding highly enantiomerically enriched ɛ-lactones. Besides the oxidation activity, the biocatalysts were also able to the reduction of carbonyl group. Only cis-methylcyclohexanols turned out to be further transformed to lactones. Biotransformations of optically enriched ketones and alcohols were also studied to give an overall view of stereoselectivity of the enzymes involved in biocatalytic pathway.
Enzyme and Microbial Technology 08/2009; 45(2):156–163. · 2.97 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: alpha-Linolenic acid (ALA) was incorporated at 28% into the sn-1 position of egg-yolk phospatidylcholine using Novozyme 435 in one-step transesterification process. Using phospholipase A(2) in a two-step process gave 25% incorporation of ALA into the sn-2 position.
[Show abstract][Hide abstract] ABSTRACT: This study shows a possible microbial process for utilization of crude glycerol generated by the biodiesel industry for citric
acid and erythritol production. Simultaneous production of citric acid and erythritol under nitrogen-limited conditions with
glycerol as the carbon source was achieved with an acetate negative mutant of Y. lipolytica Wratislavia K1 in fed-batch cultivations. The effect of the initial glycerol concentration (from 30–180 g dm−3) on the citrate and erythritol production was investigated. As a result of the experiments, maximum citric acid production
(110 g dm−3) and a very high amount of erythritol (81 g dm−3) were determined after 168 h of fed-batch cultivation with the initial glycerol concentration of 150 g dm−3 and the total glycerol concentration of 250 g dm−3. In addition, the citric acid to isocitric acid ratio of the products from this strain was 35.5:1.
Chemical Papers- Slovak Academy of Sciences 06/2008; 62(3):239-246. · 1.19 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The strain Absidia cylindrospora was chosen among eight fungal strains for the biotransformation of unsaturated lactones 1a–c. The processes were carried out by means of shaken cultures. The compounds 1a and 1b were efficiently converted into the corresponding trans-epoxylactones (2a and 2b), whereas the transformation of 1c gave the unsaturated hydroxylactone 3, with the tertiary hydroxy group introduced in the allylic position. The compound 2b was obtained with 100% ee. The structures of compounds 2a and 2b were fully confirmed by the X-ray analysis, which showed the half boat and half chair conformation of cyclohexane ring in these molecules, respectively. All the products were not reported previously in the literature.
Journal of Molecular Catalysis B Enzymatic 11/2007; · 2.75 Impact Factor