• Applied Chemistry for Engineering
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• v.16 no.3
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• pp.456-459
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• 2005

UV spectrometric assay for measurement of epoxide hydrolase activity was tested for efficient screening of whole cell activity of epoxide hydrolase. Epoxide hydrolase activities were determined by measuring the amount of p-nitrostyrene diol (pNSD), which was the hydrolysis product of p-nitrostyrene oxide (pNSO). Enantioselective hydrolysis of racemic pNSO using epoxide hydrolase activity of Rhodosporidium toruloides was monitored by UV spectrometric assay, and the relevant $K_m$ and $V_m$ for R. toruloides were determined as $2.457nmol/min{\cdot}mg$ and 1.078 mM, respectively.

• Journal of Life Science
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• v.15 no.1 s.68
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• pp.136-140
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• 2005

Microbial cell-based UV spectrometric assay for the quantitative measurement of epoxide hydrolase activity was evaluated and optimized for the efficient screening of whole cell activity of novel epoxide hydrolase. Epoxide hydrolase activity was determined by measuring the increase of the oxidized product, benzaldehyde. The effects of the concentrations of phenyl-1,2-ethanediol, sodium metaperiodate and cells were optimized for epoxide hydrolase-catalyzed hydrolysis of styrene oxide. The relevant kinetic parameters of Km and $V_{max}$ for the hydrolysis of (R)-styrene oxide by Rhodotorula glutinis were determined from Lineweaver-Burk plot as 41.2 nmol/min$\cdot$mg dcw and 7.5 mM respectively, and coincided well with those from GC analysis.

• Fisheries and Aquatic Sciences
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• v.16 no.4
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• pp.237-242
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• 2013

We investigated the antioxidant and angiotensin I converting enzyme (ACE) inhibitory activities of red snow crab Chionoecetes japonicas shell (RSCS) hydrolysate by enzymatic hydrolysis and its molecular weight cut-off fractions. The RSCS hydrolysate was fractionated through two ultrafiltration membranes of 3 and 10 kDa cut-offs. Three fractions (<3 kDa, 3-10 kDa, and >10 kDa) were evaluated for total amino acid composition, antioxidant activities using 2'-azino-bis[3-ethylbenzthiazoline-6-sulfonic acid] ($ABTS^+$) radical scavenging and superoxide dismutase (SOD)-like activities and reducing power assays, and ACE inhibitory activity using Hou's method. Although all fractions showed activity, the <3 kDa fraction of RSCS hydrolysate exhibited the greatest $ABTS^+$ radical scavenging, SOD-like and ACE inhibitory activities. However, these fractions exhibited low reducing power. These results suggest that the low-molecular-weight enzymatic hydrolysate of RSCS could be used as a functional ingredient to control oxidative stress and ACE activity.

• Journal of Powder Materials
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• v.12 no.1
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• pp.51-55
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• 2005

$Cu_2O$ nano cubes with high catalase activity were synthesized by reduction of freshly prepared Cu in distilled water at $40^{\circC}$ and their catalase activities of $H_2O_2$ were studied. Transmission electron microscopy (TEM) observation showed that most of these nanocubes were uniform in size, with the average edge length of 30 nm. Selected area electron diffraction of TEM revealed that the nanocube consisted of single crystalline $Cu_2O$, but it changed to CuO phase. The catalase activity depends on the amount of both cuprite phase and surface area.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.49 no.3
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• pp.259-267
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• 2023

This study was conducted to evaluate physiological activity of flower extract of peony (Paeonia lactiflora Pall.) by hydrolysis and to use it as a valuable cosmetic ingredients. Four cultivar of peony flowers were extracted, and the highest active ingredient contents was selected, and that cultivar was used for hydrolyzing. The results showed that high concentration of hydrochloric acid (HCl) hydrolyzed, and biological hydrolysis using enzymes had no activity. The deglycosylation of peonidin 3,5-diglucoside occurred by hydrolysis. The hydrolysate contains 63.3 ppm of peonidin, a red-colored anthocyanin compound. The antioxidant activity of hydrolysate was compared with extract. The results showed the strong antioxidant activity in hydrolysate (96%) than extract (82%). In addition, hydrolysate of peony flower showed higher inhibitory activity of NO release than extract. UVA assay using fibroblast cell (CCD-986Sk) showed that hydrolysate increased cell viability than extract under UVA exposure. Based on these results, we anticipate that hydrolysate of peony flower can be used a valuable cosmetic ingredient.

• Journal of Microbiology
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• v.38 no.4
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• pp.224-229
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• 2000

Chitin-degrading marine bacterial strain 98CJ11027 was isolated from bryozoa from the coastal area of Cheju Island, Korea, and identified as a member of the genus Vibrio. The molecular mass of the main extracellular chitinase (chitinase I), purified from strain 98CJ11027, was estimated to be 98 kDa. The optimal condition for chitinase I activity is pH 6.0 and 45$^{\circ}C$. The activity was inhibited by Fe$\^$+2/ and Cu$\^$+2/. Chitinase I displayed the hydrolysis type of chitobiosidase and catalyzed reversed hydrolysis leading to the synthesis of tetraacetylchitotetraose.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.6
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• pp.670-677
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• 2011

This study is to optimize the enzymatic processing conditions of Polylactic Acid (PLA) fiber using lipase from Porcine pancreas as an environmental technology. Hydrolytic activity dependent on pH, temperature, enzyme concentration, and treatment time, and structural change of PLA fiber were evaluated. The PLA fiber hydrolysis by lipase was maximized at 50% (o.w.f) lipase concentration $50^{\circ}C$ for 120 minutes under pH 8.5. There was a change of the protein absorbance in the treatment solution before and after the lipase treatment. In addition, there was no substantial change in the molecular and crystalline structures of PLA by lipase treatment as confirmed by DSC, XRD, and FT-IR.

• Journal of Microbiology and Biotechnology
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• v.16 no.12
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• pp.1897-1903
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• 2006

In order to investigate the functions of the C-terminal region of chitinase ChiCW of Bacillus cereus 28-9, a C-terminal truncated enzyme, ChiCW$\Delta$FC, was expressed in Escherichia coli and purified to homogeneity for biochemical characterization. Compared with ChiCW, ChiCW$\Delta$FC exhibited higher chitinase activity at high temperature and pH, but expressed lower hydrolytic and binding activities toward insoluble substrates. In addition, kinetic properties indicated that ChiCW$\Delta$MC hydrolyzed oligomeric and polymeric substrates less efficiently than ChiCW. These results suggest that the C-terminal region of ChiCW plays important roles in substrate binding and hydrolysis of chitin. In addition, the biological meaning of C-terminal proteolytic modification of ChiCW is discussed.

• Microbiology and Biotechnology Letters
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• v.25 no.2
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• pp.115-120
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• 1997

Penicillium sp.-L4, a causative fungus of rot in citrus fruits, was isolated and its mode of hydrolytic enzyme production was investigated. Carboxymethylcellulase (CMCase), polygalacturonase(PGase), extra- & intra-cellular $\beta$-glucosidase and cellobiase were produced drastically by addition of substrates in minimal media. Production of the hydrolytic enzymes were induced efficiently by cellobiose and cellooligosaccharides which were the products of cellulose hydrolysis, but repressed by addition of mono-saccharide such as glucose, raffinose, galacturonic acid. The relative activity of p-nitrophenyl-$\beta$-D-glucopyranoside(PNPG) hydrolysis was higher than that of cellobiose hydrolysis in extracellular enzymes, and reverse is true in intracellular enzymes. Intact enzyme production of P. sp.-L4 on lemon peel lesion was sequential. $\beta$-Glucosidase and CMCase were produced first and followed by PGase. The enzyme productivities and pH in lesions were coincident with optimal pH of each enzyme activities.

• KSBB Journal
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• v.13 no.1
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• pp.20-25
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• 1998

Optimum conditions of the cellulose-hydrolysis reaction with mixed enzymes(cellulase extracted from Penicellium funiculosum mixed with $\beta$-glucosidase extracted from Almod) were investigated to increase the production of glucose from cellulose. Experimental result showed that optimum conditions fro pH, activity ratio of $\beta$-glucosidase to cellulase, concentration of mixed enzymes, concentration of cellulose as a substrate, and temperature range were 4.2, 0.4, 0.8, U/mL, 40 g/L, and 37$\pm$3$^\circ C$, respectively. In these conditions, quantities of glucose productions by using mixed enzymes were larger than those by using cellulase at optimum conditions.