• KSBB Journal
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• v.15 no.3
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• pp.313-317
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• 2000

In this paper enantioselective production of levofloxacin by porcine liver esterase was investigated, To enhance the produc0-tivity various factors which affect the enzyme activity and the enantioselectivity were optimized, In terms of temperature and pH 45$^{\circ}C$ and 4.8 were found to be the best conditions for enzyme reaction. Addition of ofloxacin butyl ester the substrate at the concentration of 5 g/L was desirable to avoid the product inhibition and the activity of porcine liver esterase was maintained up to 72 hours.In addition to enhance the availability of substrate effect of solvent was also examined. It was found that the application of 5% (v/v) of acetone acetonitrile and dimethylsulfoxide did not increase the conversion of substrate and the presence of 5%(v/v) butanol inhibited the enzyme activity significantly.

• Biomolecules & Therapeutics
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• v.18 no.4
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• pp.433-441
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• 2010

Chenopodium album Linne (CAL) is a fast-growing weedy annual plant. The leaves and young shoots may be eaten as a leafy vegetable. In oriental medicine, CAL has been used for treatment of skin disease, fever, stomach ache, toothache, and paralysis. After a preliminary screening of CAL ethanol extract and its fractions obtained from CAL leaves for anti-gastritic and anti-Helicobacter pylori (H. pylori) activity, the butanol (BuOH) fraction was found to have the most significant effect. We also examined antioxidative properties of the total CAL extract and its fractions, and also betaine as an ingredient of the BuOH fraction. To investigate the antioxidant effects of CAL on gastritis, the reducing power, free radical scavenging activity using 1,1-diphenyl-2-picrylhydrazyl (DPPH), and lipid peroxidation effects were determined. Additionally, the BuOH fraction reduced cell viability in a concentration dependent manner in human gastric cancer cell lines. The results of this study revealed that CAL has excellent antioxidant activity, and may be useful in treating gastritis and gastric cancer.

• Microbiology and Biotechnology Letters
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• v.27 no.3
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• pp.197-202
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• 1999

To confirm the effects of binlang(Areca catechu L.) and tansen(Salvia miltriorrhiza bung) on the mutagenicity induced by hydrogen peroxide, SOS Chromotest with Escherichia coli PQ37 and Ames test with Salmonella typhimurium TA104 were perlormed. Methanol-soluble parts of their water extracts showed high inhibitory effect against the mutagenicity of hydrogen peroxide in two bacterial mutation assays. Step-wise fractionation of methanol-soluble part from tansen was done using ethyl acetate, butanol and water. Among these fraction was further partitioned by Sephadex LH-20 column chromtography, and 6 subfractions were obtained. The fraction III showed the strongest inhibitory effects against the mutagenic activities induced by hydrogen peroxide. The inhibition rates of fraction III at concentration of 500$\mu\textrm{g}$/assay were 28%, 30% and 15% against 4-NQO, MNNG and B(a)P, respectively. But the mutagenic potency of AFB1 was increased.

• Microbiology and Biotechnology Letters
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• v.24 no.6
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• pp.687-692
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• 1996

Xylanase (EC 3.2.1.8) was purified approximately 4.3 fold from Aspergillus niger SFN-416 by ammonium sulfate fractionation, Sephadex G-100 gel filtration and DEAE-Sephacel ion exchange chromatography. Molecular weight of the enzyme was approximately 42,000 daltons. The optimum pH and temperature of the enzyme activity were 5.5 and 50$\circ$C, respectively. The enzyme activity was enhanced by Fe$^{2+}$, and inhibited by Hg$^{2+}$. The activity was decreased by addition of methanol, ethanol, isopropanol and 1-butanol at a concentration of 10%(v/v).

• Journal of the Korean Applied Science and Technology
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• v.21 no.1
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• pp.37-44
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• 2004

Glycosyl acrylate and methacrylate were synthesized by lipase-catalyzed esterification of vinyl acrylate and vinyl methacrylate with ${\beta}$-methyl glucoside in t-butanol as a reaction medium. At the optimum conditions of initial concentration of 150g/l ${\beta}$-methyl glucoside, molar ratio of 1 : 3, 5%(w/v) lipase(Novozym 435) and $50^{\circ}C$, we attained up to 100% conversion for enzymatic glycosylation of vinyl acrylate and vinyl methacrylate by supersaturated solvent process. The polymerizable glycosyl acrylates and methacrylate are expected to have biomedical application as hydrophilic monomers and hydration modifiers to be used for biocdmpatible hydrogel.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.602-608
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• 1995

The aim of the present research program was to construct an optimum fermentation system and to characterize the properties of cathepsin B inhibitor from Streptomyces chromofuscus SMF28. Glucose and casitone were proved to be good carbon source and nitrogen source, respectively. The production of inhibitor was high at lower concentration than 10 mM of inorganic phosphate. The optimum temperature and pH for the production of inhibitor were 30$\circ$C and pH 7, respectively. The production of inhibitor was related to mycelial growth and was affected by medium composition. The inhibitor in culture filtrate of S. chromofuscus SMF28 was purified by butanol extraction, silica gel chromatography, Amberlite IRC-50 (H$^{+}$ form) chromatography, preparative TLC, and preparative HPLC. From amino acid analysis and UV, IR, $^{1}$H-NMR spectroscopic analysis, the inhibitor was identified as a peptide containing valine and phenylalanine derivative.

• Proceedings of the Korean Society of Applied Pharmacology
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• 2003.11a
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• pp.97-97
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• 2003

This study is investigated the effect of Rubus coreanus MIQ. against nephrotoxicity induced by cisplatin in rat. We examined the potency of the extract of R. coreanus fruits by the activity-guided fractionation. The EtOAc- and BuOH fraction, niga-ichigoside F$_1$and 23-hydroxytormentic acid showed significant protective effects as lipid peroxidation in renal tissue and was was not affect the activity of xanthine oxidase and aldehyde oxidase by cisplatin-induced nephrotoxicity. The concentration of glutathione in renal tissue was decreased by cisplatin-induced nephrotoxicity, but was improved by pretreatment of R. coreanus compounds especially in butanol, ethylacetate fraction and 23-hydroxytormentic acid.

• Journal of Korean society of Dental Hygiene
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• v.7 no.1
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• pp.53-59
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• 2007

Yam was stepwise extracted with hexane, chloroform, ethyl acetate, butanol, and water. Antibacterial activity of each extract was investigated. 1. Methanol extract of Yam was examed against to antibacterial effects on S. mutans KCTC 5316, P. gingivalis KCTC 5352, S. aureus KCTC 1927 by means of agar diffusion method. 2. The methanol extract of Yam was showed very powerfull antibacterial activity on S. mutans, but not showed on P. gingivalis, and S. aureus. 3. The MIC of Yam hexane fraction was 0.25 mg/ml for S. mutans KCTC 5316. 4. The Yam hexane fraction strong inhibited the growth of S. mutans, in the culture medium at concentration of 0.25 mg/ml.

• Korean Journal of Pharmacognosy
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• v.26 no.4
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• pp.377-384
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• 1995

We studied the effects of the methanolic extracts and fractions from leaves, fruits, stems and roots of Curadrania tricuspidata on the formation of lipid peroxide. The methanol extracts of leaves, fructus and stem of this plants decreased the formation of lipid peroxide in the isolated rat liver. The ethyl acetate fraction of leaves and n-butanol fraction of stems reduced the lipid peroxide formation. It showed that arthocarpesin, one of the constituents isolated from this plant, lowered the formation of lipic peroxide by 13%, 21%, 22% and 25% at the concentration of $10^{-8},\;10^{-6},\;10^{-4}\;and\;10^{-2}mg/ml$, respectively.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.317-320
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• 2002

To search for antioxidant compounds from plant resources, ethanol extracts of 10 plants species were investigated using DPPH method and SOD activity by NBT method. The highest activity was shown in the ethanol extracts of Schizandra Chinesis Baillon. And than, antioxidant effects and total polyphenol concentration were investigated in solvent fraction of ethanol extracts from Schizandra Chinesis Baillon. The DPPH inhibitory activity and SOD activity of ethyl acetate fraction (DPPH 51.6%, SOD 66.2%) and butanol fraction(DPPH 60.7%, SOD 67.4%) showed strong biological activities.