• Food Science and Biotechnology
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• v.16 no.2
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• pp.243-248
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• 2007

A biochemical characterization of the tannases from Paecilomyces variotii (produced at Unicamp), Aspergillus niger (purchased from Industrial Kerry Bio-Science) and A. niger cnpat 001 (purchased from Embrapa Agroindustrial Tropical-Brazil) was carried out. P variotii is a new strain obtained from the screening of 500 fungi that were tested for their production of tannase. The biochemical properties of this new tannase from P variotii were determined and compared with those of two other tannase preparations. The tannase produced from P. variotii showed optimum activity at pH 6.5. The functional temperature range of the tannases was from $20-70^{\circ}C$, with optima at $70^{\circ}C$ for P. variotii and at $60^{\circ}C$ for the commercially obtained tannase, whereas A. niger cnpat 001 showed optimum activity at $40^{\circ}C$. The effects of 1 mM preparations of cations and anions, inhibitors, surfactants, and chelators on the tannase activity from P. variotii were also studied.

• Korean Journal of Veterinary Service
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• v.30 no.3
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• pp.363-374
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• 2007

A biochemical characterization and antimicrobial drugs susceptibility study was conducted in four breeding kennel which was canine abortion caused by Brucella canis in Gyeongbuk province in 2003-2006. Total of 267 dogs domesticated in the four kennel were examination. Among them, 143 (53.6%) dogs were sero-positive and 25 of blood samples were isolated to Brucella canis. At amplification of 35KDa-BCSP gene using PCR, 711 bp DNA fragment was same visible in 25 isolates and B canis RM6/66. Biochemical characterization of B canis isolated was non-hemolytic, no production of $H_2S$, no fermentation of carbohydrates, catalase-positive, oxidase-positive, indol-negative, hydrolyzation of urea, reduction of nitrate and development of thionin dye medium. Using disk-diffusion method, all of 25 strains tested were found to be highly susceptible to tetracycline, aminoglycoside, quinolone, macrolide antibiotics, rifampin and ampicillin in vitro. Using PFGE with restriction enzyme Smi I, 25 isolates tested were typed to 2 pattern, S1 and S2.

• 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.

• Journal of Microbiology and Biotechnology
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• v.19 no.11
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• pp.1342-1347
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• 2009

We have isolated endophytic fungi from the Indian yew tree, Taxus baccata, and then screened for taxol production. Out of the 40 fungal cultures screened, one fungus Gliocladium sp. was found to produce taxol and 10-DABIII (10-deacetyl baccatin III). These compounds were purified by TLC and HPLC and characterized using UV-spectroscopy, ESI-MS, MS/MS, and proton NMR. One liter of Gliocladium sp. culture yielded $10\;{\mu}g$ of taxol and $65\;{\mu}g$ of 10-DABIII. The purified taxol from the fungus showed cytotoxicity towards cancer lines HL-60 (leukemia), A431 (epidermal carcinoma), and MCF-7 (breast cancer).

• Journal of Microbiology
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• v.44 no.1
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• pp.113-120
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• 2006

Candida tropicalis was treated with ultraviolet (UV) rays, and the mutants obtained were screened for xylitol production. One of the mutants, the UV1 produced 0.81g of xylitol per gram of xylose. This was further mutated with N-methyl-N'-nitro-N-nitrosoguanidine (MNNG), and the mutants obtained were screened for xylitol production. One of the mutants (CT-OMV5) produced 0.85g/g of xylitol from xylose. Xylitol production improved to 0.87 g/g of xylose with this strain when the production medium was supplemented with urea. The CT-OMV5 mutant strain differs by 12 tests when compared to the wild-type Candida tropicalis strain. The XR activity was higher in mutant CT-OMV5. The distinct difference between the mutant and wild-type strain is the presence of numerous chlamvdospores in the mutant. In this investigation, we have demonstrated that mutagenesis was successful in generating a superior xylitol-producing strain, CT-OMV5, and uncovered distinctive biochemical and physiological characteristics of the wild-type and mutant strain, CT-OMV5.

• Korean Journal of Veterinary Research
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• v.37 no.4
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• pp.773-777
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• 1997

A retrospective study of 132 cases of natural Escherichia coli infection in preweaning piglets with diarrhea submitted to the Department of Veterinary Pathology in Seoul National University from 1995 to 1996 was performed to determine the biochemical characteristics and antibiotics susceptibility. Most field isolates were lysine decarboxylase-positive (99.2%), phenylalanine decarboxylase-negative (100%), and fermented sorbitol (91.7%). Antibiotic susceptibilities will be determined by agar diffusion method. A large percentage of isolates were resistant to many antibiotics in common usage. Most isolates were susceptible to colistin (98.8%), gentamycin (64.3%), amikacin (100%), and ceftiour sodium (64.2%), whereas most isolates were notably resistant to ampicillin (86.9%), neomycin (66.7%), streptomycin (84.5%), tetracycline (98.8%), penicillin (98.8%), and amoxacillin (58.3%).

• Korean Journal of Veterinary Service
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• v.32 no.2
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• pp.139-146
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• 2009

Bovine brucellosis is a zoonosis, long incubation period and chronic infectious disease, usually caused by Brucella abortus. This study was carried out to investigate the biotyping and biochemical characterization of B. abortus isolated from 208 farm 871 korean cattle and holstein diagnosed brucellosis by serological positive in Gyeongbuk province during the period from 2002 to 2006. B. abortus was isolated from 124 (14.2%) of 871 cattle, and isolated 110 (13.4%) of 820 Korean cattle and 14 (27.5%) of 51 holstein in breed. The uterus of korean cattle was isolated in 8 (17.8%) of 45 cattle and supramammary lymph none of holstein was isolated 11 (68.8%) of 16 cattle. 101 (12.5%) of 810 serological positive blood samples were isolated B. abortus. The isolation rate of B. abortus was correlated with antibody titers. The biochemical characterization of isolates was non-hemolytic, production of H$_2$S, oxidase-positive, catalase-positive, hydrolyzation of urea and growth of basic fuchsin dye medium. As a result, all of isolates was identified B. abortus bv 1. 124 isolates were susceptible to ampicillin, lincospectin, amikacin, gentamicin, kanamycin, neomycin, streptomycin, tetracycline, ciprofloxacin, norfloxacin and enrofloxacin.

• Bulletin of the Korean Chemical Society
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• v.30 no.1
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• pp.172-176
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• 2009

The nature and morphology of titanium dioxide films play a significant role in determining the overall efficiency of dye-sensitized solar cell (DSSCs). In this work, the preparation of nanostructured titania particles by sol-gel method (SG-$TiO_2$) and its characterization were investigated for the application of DSSCs. The samples were characterized by XRD, XPS, FE-SEM, BET and FT-IR analysis. The energy conversion efficiency of SG-$TiO_2$ was approximately 8.3 % under illumination with AM 1.5 (100 mW/$cm^2$) simulated sunlight. DSSCs made of SG-$TiO_2$ nanocrystalline films as photoanodes achieved better energy conversion efficiency compared to those prepared using commercially available Degussa P25.

• 한국생물공학회:학술대회논문집
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• 2005.04a
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• pp.350-350
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• 2005

• The Zoological Society Korea : Newsletter
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• v.12 no.2
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• pp.115.2-115
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• 1995

No Abstract, See Full Text