Immobilization of Lecitase® Ultra onto a Novel Polystyrene DA-201 Resin: Characterization and Biochemical Properties

Enantioselective resolution of (R,S)-DMPM to prepare (R)-DMPM by an adsorbed-covalent crosslinked esterase PAE07 from Pseudochrobactrum asaccharolyticum WZZ003

(R)-N-(2,6-dimethylphenyl) aminopropionic acid methyl ester ((R)-DMPM) is an important chiral intermediate of the fungicide N-(2,6-Dimethylphenyl)-N-(methoxyacetyl)-alanine methyl ester ((R)-Metalaxyl). In this study, (1) D3520 (macroporous acrylic anion resin), selected from the ten resins, was used to immobilize the esterase from Pseudochrobactrum asaccharolyticum WZZ003 (PAE07) for resoluting the (R,S)-DMPM to obtain (R)-DMPM. (2) Up to 20 g/L PAE07 could be immobilized onto D3520 with a high enzymatic activity of 32.4 U/g. Moreover, the Km and Vmax values of 19.1 mM and 2.8 mM/min for D3520-immobilized PAE07 indicated its high activity and stereoselectivity. (3) The optimal temperature and pH for the immobilized PAE07 were 40 ℃ and 8.0, and substrate concentration was up to 0.35 M. After 15 h reaction, the conversion rate from (R,S)-DMPM to (R)-DMPM was 48.0% and the e.e.p and E values were 99.5% and 1393.0, respectively. In scale-up resolution, 200 g/L substrate and 12.5 g immobilized esterase PAE07 condition, a conversion rate from substrate to product of 48.1% and a product e.e.p of 98% were obtained within 12 h, with the activity of immobilized PAE07 retained 80.2% after 5 cycles of reactions. These results indicated that the D3520-immobilized esterase PAE07 had great potential for enzymatic resolution of (R,S)-DMPM to prepare (R)-Metalaxyl.

Immobilization of Candida antarctica Lipase A onto Macroporous Resin NKA-9: Esterification and Glycerolysis Performance Study

In this study, lipase A from Candida antarctica (CALA) was immobilized onto the macroporous resin NKA-9. Immobilization conditions (pH, time and CALA concentration) were studied, enzymatic activity and immobilization efficiency (IE) up to 968.89 U/g and 53.19% were respectively obtained under optimal conditions (immobilization pH 5.0, time 5 h and CALA concentration at 30 mg/mL). Then, the NKA-9 supported CALA (CALA@NKA-9) samples were used to catalyze glycerolysis in solvent-free system. With 0.25 g of the present CALA@NKA-9 (soybean oil 3.52 g and glycerol 0.184 g) and after 12 h reaction at 50 °C, diacylglycerols (DAG) content up to 64.37% and triacylglycerols (TAG) conversion at 83.33% were obtained. The relationship between temperature and TAG conversion was LnV ₀ = 13.9310-6.4212/T for CALA@NKA-9. Meanwhile, the activation energy (Ea) of CALA@NKA-9 was calculated to be 53.39 kJ/mol. In addition, reusability in the glycerolysis reaction was also evaluated, and 57.82% of the initial glycerolysis activity was retained after 9 consecutive applications. Furthermore, the CALA@NKA-9 was also used to catalyze the esterification (esterification of fatty acids with glycerol), however, the present CALA@NKA-9 cannot initiate the esterification. Therefore, the present CALA@NKA-9 is shown to be potential for DAG production through glycerolysis reaction.

Enantioselective Transesterification of Allyl Alcohols with (E)-4-Arylbut-3-en-2-ol Motif by Immobilized Lecitase™ Ultra

Lecitase™ Ultra was immobilized on four different supports and tested for the first time as the biocatalyst in the kinetic resolution of racemic allyl alcohols with the (E)-4-arylbut-3-en-2-ol system in the process of transesterification. The most effective biocatalyst turned out to be the enzyme immobilized on agarose activated with cyanogen bromide (LU-CNBr). The best results (E > 200, ees and eep = 95–99%) were obtained for (E)-4-phenylbut-3-en-2-ol and its analog with a 2,5-dimethylphenyl ring whereas the lowest ee of kinetic resolution products (90%) was achieved for the substrate with a 4-methoxyphenyl substituent. For all substrates, (R)-enantiomers were esterified faster than their (S)-antipodes. The results showed that LU-CNBr is a versatile biocatalyst, showing high activity and enantioselectivity in a wide range of organic solvents in the presence of commonly used acyl donors. High operational stability of LU-CNBr allows it to be reused in three subsequent reaction cycles without negative effects on the efficiency and enantioselectivity of transesterification. This biocatalyst can become attractive to the commercial lipases in the process of the kinetic resolution of allyl alcohols.

Free and Immobilized Lecitase™ Ultra as the Biocatalyst in the Kinetic Resolution of (E)-4-Arylbut-3-en-2-yl Esters

The influence of buffer type, co-solvent type, and acyl chain length was investigated for the enantioselective hydrolysis of racemic 4-arylbut-3-en-2-yl esters using Lecitase™ Ultra (LU). Immobilized preparations of the Lecitase™ Ultra enzyme had significantly higher activity and enantioselectivity than the free enzyme, particularly for 4-phenylbut-3-en-2-yl butyrate as the substrate. Moreover, the kinetic resolution with the immobilized enzyme was achieved in a much shorter time (24–48 h). Lecitase™ Ultra, immobilized on cyanogen bromide-activated agarose, was particularly effective, producing, after 24 h of reaction time in phosphate buffer (pH 7.2) with acetone as co-solvent, both (R)-alcohols and unreacted (S)-esters with good to excellent enantiomeric excesses (ee 90–99%). These conditions and enzyme were also suitable for the kinetic separation of racemic (E)-4-phenylbut-3-en-2-yl butyrate analogs containing methyl substituents on the benzene ring (4b,4c), but they did not show any enantioselectivity toward (E)-4-(4’-methoxyphenyl)but-3-en-2-yl butyrate (4d).

Immobilization of Aspergillus niger lipase onto a novel macroporous acrylic resin: Stable and recyclable biocatalysis for deacidification of high-acid soy sauce residue oil

Deacidification of high-acid soy sauce residue (SSR) oil is crucial to utilization of SSR oil. Aspergillus niger lipase (ANL) has been widely applied for such purpose while its immobilization still has large room for improvement. ANL was immobilized onto six different macroporous acrylic resins, accounting the effect of the different textural properties of resins on stability and their potential for application in enzymatic deacidification. The resin MARE with lower porosity, higher bulk density, and medium hydrophobicity, was chosen as the best carrier for the best thermostability and reusability. ANL-MARE is a promising catalyst than Novozym 40086, which not only exhibited higher deacidification activity and good thermostability, but also was continuously reused for 15 cycles and efficiently catalyzed from high-acid SSR oil into diacylglycerol-enriched oil. Therefore, immobilized ANL was a novel, low-cost and recyclable biocatalyst that could be used as a good alternative to higher-cost commercial lipases in industrial applications.

Production of D-allose from D-fructose using immobilized L-rhamnose isomerase and D-psicose 3-epimerase

D-Allose is a rare sugar, can be used as an ingredient in a range of foods and dietary supplements, has alimentary activities, especially excellent anti-cancer effects and used in assisting cancer chemotherapy and radiotherapy, etc. To develop a simple and low-cost process for D-allose production, a one-pot enzymatic process using the substrate of D-fructose, and the recombinant enzymes of D-psicose 3-epimerase (DPE) and L-rhamnose isomerase (L-RhI) was developed. These enzymes were cloned from Ruminococcus sp. and B. subtilis, respectively, successfully expressed in E. coli, extracted and immobilized using anion exchange resin and amino resin, respectively. The mass ratio of D-fructose, D-psicose and D-allose was 6.6:2.4:1.0 when the reaction reached equilibrium after 5 h of reaction. Using the low-cost substrate of D-fructose, the reusable immobilized enzymes and the one-pot reaction, the production process is simplified and the production cost is decreased. In addition, to simplify the enzyme extraction and immobilization processes, new methods for enzyme capture and immobilization were developed especially for DPE immobilization. This is the first report for one-pot D-allose production using immobilized L-RhI and DPE.

Functionalized Magnetic Bacterial Cellulose Beads as Carrier for Lecitase® Ultra Immobilization

Bacterial cellulose spheres subjected to amination and inlaid modification with superparamagnetic molecules were analyzed with regard to possibility of their application as an immobilization carrier of Lecitase® Ultra (LU) enzyme. The starting point to obtain the carrier was synthesis of bacterial cellulose spheres performed in shaking cultures of Komagataeibacter xylinus. These spheres were subsequently subjected to a multi-stage modification to increase the efficiency of the immobilization process and to separate product from the reaction medium. Maximal yield of Lecitase® Ultra immobilization equaled 70%. It was also found that immobilization process did not affect the pH and LU temperature optimum. Moreover, immobilized enzyme exhibited similar temperature stability profile as its native form. The immobilization process did not significantly affect the enzyme K_M value. The immobilized enzyme retained over 70% of its initial activity after 8 cycles of use. The immobilized enzyme displayed good storage stability and retained 80% of its initial activity after 4 weeks at 4 °C. The potential application of such modified cellulose-based carrier may be correlated with lower costs of process thanks to higher enzyme’s reusability in comparison to unbound enzyme. Moreover, data presented in the current study may serve as proof of a concept of cellulose-based carrier utilization for immobilization of enzymes other than LU and of high industrial importance.

Green Synthesis of Conjugated Linoleic Acids from Plant Oils Using a Novel Synergistic Catalytic System

A novel and efficient method has been developed for converting plant oil into a specific conjugated linoleic acid (CLA) using a synergistic biocatalytic system based on immobilized Propionibacterium acnes isomerase (PAI) and Rhizopus oryzae lipase (ROL). PAI exhibited the greatest catalytic activity when immobilized on D301R anion-exchange resin under optimal conditions (PAI dosage of 12 410 U of PAI/g of D301R, glutaraldehyde concentration of 0.4%, and reaction conditions of pH 7.0, 25 °C, and 60 min). Up to 109 g/L trans-10,cis-12-CLA was obtained after incubation of 200 g/L sunflower oil with PAI (1659 U/g of oil) and ROL (625 mU/g of oil) at pH 7.0 and 35 °C for 36 h; the corresponding conversion ratio of linoleic acid (LA) to CLA was 90.5%. This method exhibited the highest proportion of trans-10,cis-12-CLA yet reported and is a promising method for large-scale production.

Improved performance of Yarrowia lipolytica lipase-catalyzed kinetic resolution of (R,S)-2-octanol by an integrated strategy of interfacial activation, bioimprinting and immobilization

Yarrowia lipolytica lipase (YLL) demonstrated an (R)-enantiopreference for efficient resolution of (R,S)-2-octanol. The activity, enantioselectivity, the ratio of substrate to enzyme, acetaldehyde tolerance, and operational stability of YLL were improved by an integrated strategy of interfacial activation, bioimprinting, and immobilization. In comparison with the control, both the enzymatic activity and enantioselectivity increased by a factor of 8.85 and 2.75 by the integrated strategy, respectively. Fifty-one percentage of conversion with 220 of enantioselectivity was obtained using the immobilized YLL prepared by the integrated strategy at a ratio of 104 of substrate to enzyme loaded. The immobilized YLL retained 97% of its initial activity without a decrease in enantioselectivity after 10 successive reuse cycles. Together these results will result in a promising strategy with the YYL for efficient resolution of (R,S)-2-octanol in practice.