• Toxicological Research
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• v.14 no.3
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• pp.301-306
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• 1998

This experiment was carrid out to know the effects of heating and serum on hydroxyl radicals in embryonic mouse forebrain (cerebrum) culture. The heating to mouse embryonic cerebrum cells in culture was done in a water bath at 43${\circ}C$ for 60min. After that, two supernatants were prepared at 20 hrs and 48 hrs respectively after heat treatment to the brain cells. To find out the heating effects on neuron cells, mouse cerebrum cells (13 embryonic day) were cultured in hydroxyl radical generation system composed of 20mU/ml glucose oxidase (GO system), using condition of normal culture media (MEM, 5% serum, 5% $CO_2$or supernatant prepared after heating at 43${\circ}C$ for 60 min in a water bath. Supernatant prepared at 20 hrs after heat treatment had a greater protective effects against hydroxyl radical than supernatant prepared at 48 hrs after heat treatment . Otherwise, the protective effect of serum against hydroxyl radicals in the cultured brain cells is higher than that in the heat treatment. These results indicated that serum in culture media reduced cytotoxicity of hydroxyl radicals in mouse forebrain culture, also that heat treatment showed the protective effects against hydroxyl radicals generated with 20mU/ml GO system in mouse forebrain culture.

• Nutrition Research and Practice
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• v.3 no.4
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• pp.279-285
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• 2009

This study was conducted to investigate the effect of dietary grape skin on lipid peroxidation and antioxidant defense system in rats fed high fat diet. The Sprague-Dawley rats were fed either control (5% fat) diet or high fat (25% fat) diet which was based on AIN-93 diet for 2 weeks, and then they were grouped as control group (C), control + 5% grape skin group (CS), high-fat group (HF), high fat + 5% grape skin group (HFS) with 10 rats each and fed corresponding diets for 4 weeks. The hepatic thiobarbituric acid reacting substances (TBARS) were increased in high fat group as compared with control group, but reduced by grape skin. The serum total antioxidant status, and activities of hepatic catalase and superoxide dismutase, xanthine oxidase and glucose-6-phosphatase were increased by supplementation of grape skin. Glutathione peroxidase activity was significantly higher in CS group than in C group. Grape skin feeding tended to increase the concentration of total glutathione, especially in control group. The ratio of reduced glutathione to oxidized glutathione was lower in high fat groups than in control groups. The ratio was increased by dietary supplementation of grape skin in control group. These results suggest that dietary supplementation of grape skin would be effective on protection of oxidative damage by lipid peroxidation through improvement of antioxidant defense system in rats fed high fat diet as well as rats with low fat diet.

• Mycobiology
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• v.43 no.1
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• pp.37-42
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• 2015

A mutant library of Cordyceps militaris was constructed by improved Agrobacterium tumefaciens-mediated transformation and screened for degradation features. Six mutants with altered characters in in vitro and in vivo fruiting body production, and cordycepin formation were found to contain a single copy T-DNA. T-DNA flanking sequences of these mutants were identified by thermal asymmetric interlaced-PCR approach. ATP-dependent helicase, cytochrome oxidase subunit I and ubiquitin-like activating enzyme were involved in in vitro fruiting body production, serine/threonine phosphatase involved in in vivo fruiting body production, while glucose-methanol-choline oxidoreductase and telomerase reverse transcriptase involved in cordycepin formation. These genes were analyzed by bioinformatics methods, and their molecular function and biology process were speculated by Gene Ontology (GO) analysis. The results provided useful information for the control of culture degeneration in commercial production of C. militaris.

• Macromolecular Research
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• v.10 no.2
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• pp.67-74
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• 2002

New immunoprotecting membranes were prepared by spin coating the amphiphilic random multiblock copolymers of poly(ethylene glycol) (PEG) and poly(tetramethylene ether glycol) (PTMEG) or poly(dimethyl siloxane) (PDMS) on porous Durapore(R) membrane. The copolymer coating was intended to make a biocompatible, immunoprotecting diffusional barrier and the supporting porous substrate was for mechanical stability and processability. By filling Durapore(R) membrane pores with water, the penetration of coating solution into the pores was minimized during the spin coating process. A single coating process produced a completely covered thin surface layer (~1 ${\mu}{\textrm}{m}$ in thickness) on the porous substrate membrane. The permselectivity of the coated layer was influenced by PEG block length, polymer composition, and thickness of the coating layer. A composite membrane with the coating layer prepared with PEG 2 K/PTMEG 2 K block copolymer showed that its molecular weight cut-of fat any 40 based on dextran was close to the molecular size of IgG (Mw = 150 kDa). However, IgG permeation was detected from protein permeation test, while glucose oxidase (Mw = 186 kDa) was not permeable through the coated membrane.

• Pediatric Infection and Vaccine
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• v.5 no.2
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• pp.296-301
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• 1998

Flavobacterium species are nonfastidious, oxidase-positive gram-negative rods that do not ferment glucose. These organism are widely distributed in nature and in hospital environments. In past, one of flavobacteria, Flavobacterium indologenes, was treated with non-pathogenic organism. Recently, several investigators have demonstrated the infection of this organism in human. Nowadays, the growth of F. indologenes in specimen should be considered a potential pathogen in infectious patients including neonate, especially in the setting of malignancy and with use of invasive procedures. The resistance of this organism to multiple antibiotics and the high incidence of polymicrobial bacteremia make it difficult to determine optimal therapeutic options. We experienced a case of neonatal bacterial meningitis causing by F. indologenes. So we report this case to evoke more concerns about the infections of this organism in human.

• Korean Journal of Microbiology
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• v.38 no.4
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• pp.209-209
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• 2002

Mycobacterium sp. strain JCl DSM 3803 grown in methanol showed no methanol dehydrogenase or oxidase activities found in mast methylotrophic bacteria and yeasts, respectively. Even though the methanol-grown cells exhibited a little methanol-dependent oxidation by cytochrome c-dependent methanol dehydrogenase and alcohol dehydrogenase, they were not the key enzymes responsible for the methanol oxidation of the cells, in that the cells contained no c-type cytochrome and the methanol oxidizing activity from the partially purified alcohol dehydrogenase was too low, respectively. In substrate switching experiments, we found that only a catalase-peroxidase among the three types of catalase found in glucose-grown cells was highly expressed, in the methanol-grown cells and that its activity was relatively high during the exponential growth phase in Mycobacterium sp. JCl. Therefore, we propose that catalase-peroxidase is an essential enzyme responsible for the methanol metabolism directly Of indirectly in Mycobacterium sp. JCl.

• KSBB Journal
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• v.11 no.5
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• pp.593-599
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• 1996

The strain which produces agar degrading enzyme was isolated from chiton(Liolophura japonica). The strain was identified as Cytophaga sp. through its morphological, physiological, and biological characteristics. For the production of agar degrading enzyme, 0.3% nutrient broth, 0.2% yeast extract and 0.5% agar was used as nitrogen and carbon source, respectively. The optimal initial pH, NaCl and temperature for the agar degrading activity of Cytophaga sp. were 7.0, 2.0% and $30{\pm}2^{\circ}C$, respectively. Agar degrading activity of enzyme obtained from Cytophaga sp. was increased until the incubation of 96hrs, but after 96hrs, the activity was decreased.

• Journal of Physiology & Pathology in Korean Medicine
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• v.17 no.2
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• pp.499-502
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• 2003

Neurotoxicity of reactive oxygen species(ROS) and neuroprotective effect of Aconiti Radix(AR) against ROS-induced cytotoxicity were determined on cultured mouse cerebral neurons by MTT assay after cerebral neurons were cultured for 5 hours in various concentrations of GO. GO was toxic in a dose-dependent manner on cultured cerebral neurons after cerebral neurons were incubated for 5 hours in media containing 5～40mU/ml GO. While, cultures were pretreated with 180 μg/ml AR for 2 hours increased remarkably cell viability. From these results, it is suggested that GO has toxic effect on cultured mouse cerebral neurons by the decrease of cell viability. And also, herb extract such as AKR is very effective in the protection pf neurotoxicity induced by GO.

• Fisheries and Aquatic Sciences
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• v.15 no.1
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• pp.83-89
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• 2012

Flavobacterium johnsoniae was isolated from farmed rainbow trout Oncorhynchus mykiss in Korea, and its biochemical and molecular characterization was determined. Yellow-pigmented bacterial colonies were isolated from 18 of 64 fish samples (28.1%) on trypticase soy agar plates, and their biochemical profiles were characterized by API 20E and API 20NE test kits. F. johnsoniae was identified by biochemical phenotyping of factors including rapid gliding motility, Gram-negative condition, oxidase- and catalase-positive status, Congo red absorption, nitrate reduction, ${\beta}$-galactosidase production, acid production from glucose, and gelatin and casein hydrolysis. PCR and subsequent sequencing of 16S rRNA confirmed that the yellow-pigmented colonies were most similar to F. johnsoniae. The alignment analysis of 16S rRNA sequences also showed that all 18 rainbow trout isolates had highly similar homologies (97-99% identity). One isolate was selected and named FjRt09. This isolate showed 98% homology with previously reported F. johnsoniae isolates, and in phylogenetic analysis was more closely grouped with F. johnsoniae than with F. psychrophilum, F. columnare, or F. branchiophilum. This is the first report on the occurrence and biochemical characterization of F. johnsoniae isolated from rainbow trout in Korea.

• Archives of Pharmacal Research
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• v.23 no.5
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• pp.461-466
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• 2000

Tectorigenin and kaikasaponin III from the flowers of Pueraria thunbergiana showed potent hypoglycemic and hypolipidemic effects in the streptozotocin-induced diabetic rats. Intraperitoneal administration of these two compounds with 5 and 10 mg/kg, respectively, for seven days to streptozotocin-induced rats significantly reduced the blood glucose, total cholesterol, LDL- and VLDI-cholesterol and triglyceride levels when compared with those of control group. Glycitein in which 5-OH is unlinked and tectoridin (7-O-glycoside of tectorigenin) isolated from the flowers of P. thunbergiana did not improve hyperglycemia and hyperlipidemia. In addition, tectorigenin showed in vitro antioxidant effects on 1,1-diphenyl-B-pirylhydrazyl (DPPH) radical, xanthine-xanthine oxidase superoxide anion radical, and lipid peroxidation in rat microsomes induced by enzymatic and non-enzymatic methods. We further found that tectorigenin and kaikasaponin III protected the Vero cell line(normal monkey kidney) from injury by hydrogen peroxide. From these findings, it seems likely that the antioxidant action of tectorigenin and kaikasaponin III may alleviate the streptozotocin-induced toxicity and contribute to hypoglycemic and hypolipidemic effects.