• Food Science and Biotechnology
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• v.18 no.2
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• pp.574-577
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• 2009

To reduce the content of undesirable erucic acid in mustard oil (MO), it was enzymatically modified with capric acid using immobilized lipase TL IM to produce structured lipid (SL). After reaction, the content of erucic acid was reduced up to 21.7% under the performed reactions in this study. Meanwhile, unsaturated fatty acids existing at sn-2 position (oleic acid, linoleic acid, and linolenic acid) in MO were not much changed.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.142.1-142
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• 2003

Mono-, diacylglycerol were synthesized by glycerolysis of bran oil and glycerol using IM60 (an immobilized lipase) in a stirred batch reactor for 72 hours. After glycerolysis, the composition TAG, DAG, MAG in product was 41.7%, 44.7%, and 11.1%, respectively. Glycerol was separated, then this mixture product was undergone fractionation for winterization followed. The fractionation was performed using hexane and acetone solvent to reduce palmitic acid at the low temperature for overnight individually. Temperature was set -40$^{\circ}C$, -14$^{\circ}C$, -8$^{\circ}C$ and 0$^{\circ}C$, respectively. By considering results from this experiments, fractionation with hexane at -8$^{\circ}C$ was most efficient regarding to yield without crystallization.

• Journal of Life Science
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• v.25 no.3
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• pp.345-348
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• 2015

An organic solvent stable lipase from solvent-tolerant Pseudomonas sp. BCNU 171 had an optimal pH of 8 and an optimal temperature of 37℃. This crude extracellular lipase from BCNU 171 exhibited increased stability in the presence of various types of solvents at high concentrations (25%, v/v). The lipase stability was found to be highest in the presence of xylene (137%), followed by toluene (131%), octane (130%), and butanol (104%). Overall, BCNU 171 lipase tended to be more stable than immobilized commercial lipase (Novozyme435) in the presence of organic solvents. Furthermore, BCNU 171 lipase maintained about 90% of its enzyme original activity in the presence of NH₄⁺, Na⁺, Ba²⁺, Hg²⁺, Ni²⁺, Cu²⁺, and Ca²⁺ion and significantly increased its enzyme activity in the presence of various emulsifying agents. Thus, the organic solvent stable lipase from Pseudomonas sp. BCNU 171 could be usable as a potential whole cell biocatalyst and for synthetic applications of enzymes for industrial chemical processes in organic solvents without using immobilization.

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2408-2412
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• 2013

We demonstrate herein the synthesis and modification of magnetic nanoparticles and its use in the immobilization of the lipase. Magnetic $Fe_3O_4$ nanoparticles (MNPs) were prepared by simple co-precipitation method in aqueous medium and then subsequently modified with tetraethyl orthosilicate (TEOS) and 3-aminopropyl triethylenesilane (APTES). Silanization magnetic nanoparticles (SMNP) and amino magnetic nanomicrosphere (AMNP) were synthesized successfully. The morphology, structure, magnetic property and chemical composition of the synthetic MNP and its derivatives were characterized using transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-IR) analysis, X-ray diffraction, superconducting quantum interference device (SQUID) and thermogravimetric analyses (TGA). All of these three nanoparticles exhibited good crystallization performance, apparent superparamagnetism, and the saturation magnetization of MNP, SMNP, AMNP were 47.9 emu/g, 33.0 emu/g and 19.5 emu/g, respectively. The amino content was 5.66%. The AMNP was used to immobilize lipase, and the maximum adsorption capacity of the protein was 26.3 mg/g. The maximum maintained activity (88 percent) was achieved while the amount of immobilized lipase was 23.7 mg $g^{-1}$. Immobilization of enzyme on the magnetic nanoparticles can facilitate the isolation of reaction products from reaction mixture and thus lowers the cost of enzyme application.

• Journal of Sensor Science and Technology
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• v.2 no.1
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• pp.35-40
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• 1993

A FET(field effect transistor) type lipid sensor was fabricated uy immobilizing lipase enzyme on the gate of pH-ISFET($SiO_{2}/Si_{3}N_{4}$). A water soluble polymer, polyvinyl alcohol(PVA) was modified with 1-methyl-4-(formyl-styryl) pyridinium methosulfate(SbQ) to give a photosensitive membrane(PVA-SbQ) in which lipase was immobilized. The optimum photolithographic conditions were ; spin coating speed $5,000{\sim}6,000$ rpm. UV exposure time $20{\sim}30$ seconds, developing time in water $30{\sim}40$ seconds, and vacuum drying time 45 min. at room temperature with the suspension containing PVA-SbQ aqueous solution(SbQ 1mol%, 10 wt %) $200{\mu}L$, bovine serum albumin (BSA) 7.5 mg, and lipase 10 mg. The lipid sensor showed good linear calibration curve in the range of $10{\sim}100$ mM triacetin as a lipid sample.

• Safe Food
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• v.6 no.3
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• pp.3-10
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• 2011

• BMB Reports
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• v.44 no.2
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• pp.87-95
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• 2011

Enzymatic catalysis has been pursued extensively in a wide range of important chemical processes for their unparalleled selectivity and mild reaction conditions. However, enzymes are usually costly and easy to inactivate in their free forms. Immobilization is the key to optimizing the in-service performance of an enzyme in industrial processes, particularly in the field of non-aqueous phase catalysis. Since the immobilization process for enzymes will inevitably result in some loss of activity, improving the activity retention of the immobilized enzyme is critical. To some extent, the performance of an immobilized enzyme is mainly governed by the supports used for immobilization, thus it is important to fully understand the properties of supporting materials and immobilization processes. In recent years, there has been growing concern in using polymeric materials as supports for their good mechanical and easily adjustable properties. Furthermore, a great many work has been done in order to improve the activity retention and stabilities of immobilized enzymes. Some introduce a spacer arm onto the support surface to improve the enzyme mobility. The support surface is also modified towards biocompatibility to reduce non-biospecific interactions between the enzyme and support. Besides, natural materials can be used directly as supporting materials owning to their inert and biocompatible properties. This review is focused on recent advances in using polymeric materials as hosts for lipase immobilization by two different methods, surface attachment and encapsulation. Polymeric materials of different forms, such as particles, membranes and nanofibers, are discussed in detail. The prospective applications of immobilized enzymes, especially the enzyme-immobilized membrane bioreactors (EMBR) are also discussed.

• Biotechnology and Bioprocess Engineering:BBE
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• v.11 no.3
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• pp.211-214
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• 2006

Immobilized Candida antarctica lipase was used to catalyze the separation of ketoprofen into its components by means of esterification followed by the enzymatic hydrolysis of the ester product. In this study, ketoprofen underwent esterification to ethanol in the presence of isooctane. When the reaction was complete, 58.3% of the ketoprofen had been transformed into an ester. The ketoprofen remaining in solution after the reaction was complete consisted primarily of its S-enantiomer (83.0%), while the 59.4% of the ketoprofen component of the ester consisted of its R-enantiomer. We then subjected the ester product to enzymatic hydrolysis in the presence of the same enzyme and produced a ketoprofen product rich in the R-enantiomer; 77% of this product consisted of the R-enantiomer when 50% of the ester had been hydrolyzed, and 90% of it consisted of the R-enantiomer when 30% of the ester had been hydrolyzed. By contrast, the R-enantiomer levels only reached approximately 42 and 65%, respectively, when 50 and 30% of the racemic ester was hydrolyzed under the same conditions.

• KSBB Journal
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• v.27 no.1
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• pp.61-66
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• 2012

In the screening process of organic solvent tolerant bacteria showing good growth in media containing several kinds of organic solvents, one strain was isolated and identified as Bacillus sp. BCNU 5006. The strain was able to tolerate many organic solvents including benzene, toluene, xylene, octane, dodecane, butanol and ethylbenzene. Likewise, it could also utilize these solvents as the sole source of carbon with significant enzyme production. The lipolytic enzyme stability of Bacillus sp. BCNU 5006 was studied in the presence of several kinds of solvents at a 25% (v/v) concentration. The highest enzyme stability was observed in the presence of octane (107%), followed by ethylbenzene (88%), decane (86%), and chloroform (85%). Especially, BCNU 5006 lipase was determined to be more stable than immobilized enzyme (Novozyme 435) in the presence of octane, chloroform and xylene. This organic solvent tolerant Bacillus sp. BCNU 5006 could be expected as a potential bioremediation agent and biocatalyst for biodegradation and provide on organic-solvent-based enzymatic synthetic method in industrial chemical processes.

• Journal of Microbiology and Biotechnology
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• v.31 no.2
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• pp.317-326
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• 2021

Vanillyl alcohol (VA), which is abundant in Vanilla bean, has strong antioxidant activity. However, the use of VA in the food and cosmetics industries is limited, due to its low solubility in emulsion or organic solvents. Meanwhile, medium chain fatty acids and medium chain monoglycerides have antibacterial activity. We synthesized butyric acid vanillyl ester (BAVE) or caprylic acid vanillyl ester (CAVE) from VA with tributyrin or tricaprylin through transesterification reaction using immobilized lipases. BAVE and CAVE scavenged 2,2-diphenyl-1-picrylhydrazyl radicals in organic solvents. In addition, BAVE and CAVE decreased the production rate of conjugated diene and triene in the menhaden oil-in-water emulsion system. While BAVE showed no antibacterial activity, CAVE showed antibacterial activity against food spoilage bacteria, including Bacillus coagulans. In this study, the antibacterial activity of vanillyl ester with medium chain fatty acid was first revealed. Zeta potential measurements confirmed that BAVE and CAVE were inserted into B. coagulans membrane. In addition, the propidium iodide uptake assay and fluorescent microscopy showed that CAVE increased B. coagulans membrane permeability. Therefore, CAVE is expected to play an important role in the food and cosmetics industries as a bi-functional material with both antioxidant and antibacterial activities.