Resolution of racemic ketoprofen in organic solvents by lipase from Burkholderia cepacia G63

Immobilized Lipase in Resolution of Ketoprofen Enantiomers: Examination of Biocatalysts Properties and Process Characterization

In this study, lipase from Aspergillus niger immobilized by physical immobilization by the adsorption interactions and partially interfacial activation and mixed physical immobilization via interfacial activation and ion exchange was used in the kinetic resolution of the ketoprofen racemic mixture. The FTIR spectra of samples after immobilization of enzyme-characteristic signals can be seen, and an increase in particle size diameters upon immobilization is observed, indicating efficient immobilization. The immobilization yield was on the level of 93% and 86% for immobilization unmodified and modified support, respectively, whereas activity recovery reached around 90% for both systems. The highest activity of immobilized biocatalysts was observed at pH 7 and temperature 40 °C and pH 8 and 20 °C for lipase immobilized by physical immobilization by the adsorption interactions and partially interfacial activation and mixed physical immobilization via interfacial activation and ion exchange, respectively. It was also shown that over a wide range of pH (from 7 to 10) and temperature (from 20 to 60 °C) both immobilized lipases retained over 80% of their relative activity, indicating improvement of enzyme stability. The best solvent during kinetic resolution of enantiomers was found to be phosphate buffer at pH 7, which obtained the highest efficiency of racemic ketoprofen methyl ester resolution at the level of over 51%, followed by enantiomeric excess 99.85% in the presence of biocatalyst obtained by physical immobilization by the adsorption interactions and partially interfacial activation.

Co-Expression of a Thermally Stable and Methanol-Resistant Lipase and Its Chaperone from Burkholderia cepacia G63 in Escherichia coli

Biodiesel biosynthesis with enzymatic transesterification is considered green, sustainable, and environmentally friendly method. Lipase from Burkholderia cepacia G63 has excellent catalytic properties in biodiesel production. Lipase chaperones promote secretion and folding of enzymes, thereby enhancing enzymatic activity. In the current study, heterologous co-expression of lipase (lipA) and chaperone (lipB) was achieved in Escherichia coli through codon optimization. The enzymatic activity of purified and renatured lipAB was 2080.23 ± 19.18 U/g at 50 °C and pH 8.0. Moreover, lipAB showed increased resistance to pH and temperature changes, and lipAB retained stable catalytic properties after treatment with metal ions, organic solvents, and surfactants, namely Mg²⁺, methanol, and Triton-100X. Besides, using recombinant lipase lipAB as catalysts, biodiesel was synthesized using rapeseed oil under 50 °C for 72 h with a yield of 90.23%. Thus, the current study confirmed that co-expression of lipase and its chaperone is an effective strategy to enhance enzyme activity and improve the biochemical profile, meanwhile, showing that lipAB is a promising biocatalyst for biodiesel production.

Amano Lipase PS from Burkholderia cepacia- Evaluation of the Effect of Substrates and Reaction Media on the Catalytic Activity

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Lipases in the native or immobilized form have commonly been used as catalysts in the chemical and pharmaceutical industry. One of the widely available enzyme catalysts on the market is lipase from Burkholderia cepacia (BCLs), previously called Pseudomonas cepacia (PCLs). This enzyme is applied, among others, in the stereoselective acylation of molecules to achieve chiral pure enantiomers of drugs or their building blocks. In this study, Amano lipase PS (APS-BCL), which is a commercial lipase from Burkholderia cepacia (BC) was tested. The lipolytic activity of APS-BCL by hydrolysis of vegetable oils and enantioselective activity of APS-BCL by the kinetic resolution of (R,S)-1-phenylethanol with using isopropenyl acetate as an acyl donor were evaluated. An effect of reaction media with different logP values (t-butyl methyl ether, dichloromethane, diisopropyl ether, toluene, cyclohexane, n-hexane, isooctane and n-heptane) on the enantioselective activity of lipase was also studied. The high value of the enantiomeric ratio (E =308.5) with the utilization of isopropenyl acetate was achieved. Whereas, the best reaction medium turned out to be diisopropyl ether, C =47.9%, eep =98%, ees =90%, after 24 h of incubation. Moreover, the influence of ω6/ω9 polyunsaturated fatty acids (PUFAs) ratio in commercial (peanut, camelina, rape, pumpkin seed, walnut, sesame, avocado, rice, corn, black cumin, hemp, safflower, grape seed) oils was investigated for the lipase activity. For the first time, the cut-off limit of ω6/ω9 ratio was proposed. The ratio equal to or higher than 2.3 allows achieving higher lipolytic activity.

Novel Sanger's Reagent-like Styrene Polymer for the Immobilization of Burkholderia cepacia Lipase

Sanger's reaction, which was originally developed for amino acid detection, was utilized for enzyme immobilization. The newly synthesized polymer support, which was called polymer NO₂-4-fluorostyrene-divinylbenzene (pNFD), was embedded with a Sanger's reagent-like functional group for immobilizing enzymes covalently under mild reaction conditions. Using Burkholderia cepacia lipase (BCL) as the target enzyme, the immobilization efficiency and activity of pNFD-BCL reached as high as 1.2 mg·g^-1 and 33.21 U·g^-1 (a specific activity of 27 675 U·g^-1), respectively, realizing 90% activity recovery. It also improved the optimal reaction temperature of BCL from 40 to 65 °C, under which its full activity could be retained for 4 h. The new carrier also widened the pH-adaptive range of BCL as 6.5-10.0, allowing the lipase to operate normally in weak acid environment. Reusability of pNFD-BCL was significantly improved as almost no activity and/or enantioselectivity loss was observed in 200 h of triglyceride hydrolysis reaction and 17 batches of ( R, S)-1-phenylethanol resolution reaction.

Relevance and bio-catalytic strategies for the kinetic resolution of ketoprofen towards dexketoprofen

This review presents the most relevant investigations concerning the biocatalytic kinetic resolution of racemic ketoprofen to dexketoprofen for the last 22 years. The advantages related to the administration of the dex-enantiomer in terms of human health, the so called "chiral switch" in the pharmaceutical industry and the sustainability of biotransformations have been the driving forces to develop innovative technology to obtain dexketoprofen. In particular, the kinetic resolution of racemic ketoprofen through enantiomeric esterification and hydrolysis using lipases as biocatalysts are thoroughly revised and commented upon. In this context, the biocatalysts, acyl-acceptors (alcohols), reaction conditions, conversion, enantiomeric excess, and enantiomeric ratio among others are discussed. Moreover, the investigations concerning scaling up processes in order to obtain an optically pure enantiomer of the profen are presented. Finally, some guidelines about perspectives of the technology and research opportunities are given.

Molecular recognition of an acyl–enzyme intermediate on the lipase B from Candida antarctica

Ketoprofen and serine form an acyl–enzyme intermediate species that vibrates at 1756 cm⁻¹ in the infrared spectra.

Improved activity of lipase immobilized in microemulsion-based organogels for (R, S)-ketoprofen ester resolution: Long-term stability and reusability

Microemulsion-based organogels (MBGs) were effectively employed for the immobilization of four commonly used lipases. During the asymmetric hydrolysis of ketoprofen vinyl ester at 30 °C for 24 h, lipase from Rhizomucor miehei and Mucor javanicus immobilized in microemulsion-based organogels (RML MBGs and MJL MBGs) maintained good enantioselectivities (ee_p were 86.2% and 99.2%, respectively), and their activities increased 12.8-fold and 7.8-fold, respectively, compared with their free forms. They gave higher yields compared with other lipase MBGs and exhibited better enantioselectivity than commercial immobilized lipases. Immobilization considerably increased the tolerance to organic solvents and high temperature. Both MJL MBGs and RML MBGs showed excellent reusability during 30 cycles of repeated 24 h reactions at 30 °C (over 40 days). The system maintained yields of greater than 50%, while the ee_s values of RML MBGs and MJL MBGs remained nearly constant at 95% and 88%, respectively.

Conformation and catalytic properties studies of Candida rugosa Lip7 via enantioselective esterification of ibuprofen in organic solvents and ionic liquids

Enantioselective esterification of ibuprofen was conducted to evaluate the enzyme activity and ees of lipase from Candida rugosa (CRL7) in ten conventional organic solvents and three ionic liquids. Different alcohols were tested for selecting the most suitable acyl acceptor due to the fact that the structure of alcohols (branch and length of carbon chains; location of -OH functional group) could affect the enzyme activity and ees. The results of alcohol and solvent selection revealed that 1-isooctanol and isooctane were the best substrate and reaction medium, respectively, because of the highest enzyme activity and ees. Compared with the control, conformational studies via FT-IR indicate that the variations of CRL7's secondary structure elements are probably responsible for the differences of enzyme activity and ees in the organic solvents and ionic liquids. Moreover, the effects of reaction parameters, such as molar ratio, water content, temperature, and reaction time, in the selected reaction medium, were also examined.