• Korean Journal of Microbiology
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• v.34 no.3
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• pp.120-125
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• 1998

A plasmid pNPG contains a genomic DNA complementing npgA1 which is located on the left arm of linkage group I. It transformed Aspergillus nidulans at a high frequency. No abortive transformants were observed and the $Trp^+$ transformants were all $Npg^+$. The 10.4 kb Psti fragment of the genomic DNA was subcloned into pILJ16, which increased the transformation efficiency by more than 200-folds. The transformants were mitotically unstable and yielded $Arg^-$ conidia at the frequency of more than 80%. An additional gene cloned into the plasmid containing the fragment was always lost with $argB^+$ marker. These characteristics strongly indicate the possibility that the plasmids autonomously replicate. The full activity of enhanced transformation was retained on the 4.9 kb EcoRI-HaeIII fragment. The DNA segment was similar to AMA1 rather than ANS1 in function and designated AMA2.

• Korean Journal of Microbiology
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• v.47 no.1
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• pp.74-80
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• 2011

Bacteriocin-producing lactic acid bacterium having antagonistic activity against Bacillus cereus, was isolated from Kimchi. The selected strain was identified as Lactococcus lactis by the Bergey's manual and 16S rDNA analysis, and named as L. lactis ET45. The bacteriocin was stable in the pH range 3.0-11.0. The bacteriocin was active over a wide temperature range from $40^{\circ}C$ to $121^{\circ}C$. Optimal culture condition for producing bacteriocin was obtained by growing the cells on MRS medium at pH 7.5 and $30^{\circ}C$ for 18 h. Antibacterial activity of the bacteriocin was completely disappeared by proteinase K, and this means that bacteriocin is a proteinous substance. The molecular weight of bacteriocin was estimated to be about 4.5 kDa by tricine sodium dodecyl sulfate polyacryamide gel electrophoresis (TSDS-PAGE).

• The Korean Journal of Mycology
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• v.47 no.4
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• pp.393-406
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• 2019

In August 2017, anthracnose symptoms were observed on the petioles and leaf veins of Korean radish (Rhaphanus sativus) in Hongcheon, Jeongseon, and Pyeongchang of the Gangwon province, Korea. Many grayish to dark-brown spots of 1-2 mm in diameter, appeared on the lower surface and leaf veins of the radish leaves. The spots gradually enlarged and coalesced to form dark-brown irregular lesions. Ten Colletotrichum isolates were obtained from the affected tissues of the Korean radish. Out of them, eight isolates were identified as C. higginsianum and two isolates were identified as C. truncatum based on morphological characteristics and multi-locus molecular phylogenetic analysis using the internal transcribed spacers and intervening 5.8S rDNA (ITS), partial beta-tubulin gene (TUB2), partial actin gene (ACT), and partial chitin synthase-1 gene (CHS1). The pathogenicity test was carried out on wounded and unwounded Korean radish (cv. Siraegimu and Osarimu), and Chinese cabbage (cv. Chuno and Smart) by inoculating with a spore suspension. All isolates except one C. truncatum isolate developed typical symptoms on both wounded and unwounded Korean radish. In Chinese cabbage, only the plants inoculated with C. higginsianum isolates developed symptoms regardless of the wound. This is the first report of anthracnose caused by C. truncatum on Korean radish in Korea.

• Journal of Life Science
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• v.17 no.9 s.89
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• pp.1224-1231
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• 2007

Insulin-like growth factor-I (IGF-I) and IGF-II have structure like insulin. In contrast to insulin, however, the bioavaility of IGFs is modulated by the IGF-binding protein (IGFBPs). Each of IGFBPs was different with molecular masses, biological characteristics, and immunological properties.. Human fibroblasts secrete IGFBPs that can modify IGF-I action. In diabetes mellitus, the most study of IGF systems have been investigated in insulin-dependent diabetes mellitus, non-insulin-dependent diabetes mellitus, and streptozotocin-in-duced animals in vivo. Recently, a little research regarding the IGFs system has been proposed in por-tion of cell in vitro. In this study, effects of low or high glucose condition on IGFBP-5 in GM10 was investigated. By western blotting analysis, IGFBP-5 level decreased in cells cultured at high glucose, but IGFBP-5 level of mRNA didn't change. IGFBP-5 protease that cleaves IGFBP-5 in conditioned me-dium had was inhibited by EDTA and heparin, like serine protease and metalloprotease. Furthermore, the protease activity was increased in high glucose cultivated condition. In results of gelatin zymog-raphy, molecular weight of proteolytic metalloenzymes was indentified 69-kDa and protease activity was increased in time-dependent manner. Although the mechanism has yet to be determined, IGFBP-5 proteolysis in GM10 cells cultured with high glucose may increase effects of IGFs to decrease the glu-cose level through dissociation of IGFs from IGFBPs. Therefore, we suggest that IGF- I and IGFBPs could be potential models in study of pathophysiology such as diabetes mellitus.

• Korean journal of food and cookery science
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• v.9 no.4
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• pp.261-265
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• 1993

For the purpose of supplying the information to improve the acceptability of soy paste as the condi-ment, the changes of peptide were determined. The results were as follows; Average peptide length were decreased. It was 102 at 0 day, 15 at 10 day and 4.1 at 180 day. Peptide fraction were the same as in 60 day and 180 day. Low molecular weight peptide were not changed greatly during fermention. Peptide identified in 180 day fermentation were Ala-Ser, Gly-Glu, Glu-Ser, Asp-Glu, Asp- Tyr, Asp-Ala-Ser, Ala-Ser-Glu, Glu-Ser-Ala, and Ala-Lys-Met. In the characteristics of bitter peptide in 180 day fermentation, soy paste itself didn't show bitter taste', solvent extration fraction I'showed bitter taste. After gel chromatography, fraction I, fraction II and fraction III were obtained and fraction II were bitter peptide of low molecular weight. After gel chromatography', solvent extration fraction 2'(water extration) were divided into fraction IV, V, VI,VII and VIII. Fraction IV, V and VI showed bitter taste. Amino acids composition of the fractions showing bitter taste were like that; fr. 1: Glu- (Asp, Pro, Val, lie or Leu)-Met fr. II Pro-(Glu, Val, Phe)-lle or Leu fr. IV: Glu-(Asp, Ala, Tyr, Leu of lie)-Phe fr. V: Ala-(Met, Glu, Pro)-lle or Leu fr. VI: Asp-(Phe, Ser, fly)-Val.

• Journal of the Korean Society of Food Science and Nutrition
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• v.25 no.4
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• pp.659-664
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• 1996

The amount and characteristics of pectin in the albedo and flavedo layers of the citrus peels, and those of the pulp were investigated. Alcohol insoluble solid(AIS) content was the highest in albedo layer(18.1%), and the lowest in pulp(5.7%). The pulp and the albedo layer showed a potential pectin sources as containing pectins of 40.5% and 35.2% of the total polysaccharides of the pulp and the albedo layer, respectively. Total pectin contents were about 30% of the AIS and showed comparatively constant values among the byproducts. Hydrochloric acid soluble pectin contents were the hightest in the flavedo layer, 14.0%, and the lowest in the pulp, 4.4%. Over 90% of the total pectin could be extracted after 60min with 0.05N HCI at $85^{\circ}C.$ Microwave treatment reduced the extraction time significantly ; a comparable extraction yield was acquired after 10min with microwave treatment. The degree of esterification of the extracted pectin also increased with microwave treatment. Neutral sugars in the hydrolysate of the pectin were rhamnose, arabinose, galactose, glucose and xylose. No differences in molecular weight distribution of the pectin were found between the albedo and flavedo layers. Pectin of the pulp showed different molecular weight distribution from that of the peels.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.11
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• pp.537-543
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• 2019

Alumina(Al₂O₃) is a ceramic material used in industry with a range of particle sizes and characteristics. In this study, a boehmite sol was prepared by a hydrolysis and peptizing process using the Sol-Gel method from aluminum isopropoxide (AIP). γ-Al₂O₃ was prepared by drying and calcining. To prevent particle agglomeration during the manufacturing process, four kinds of polyvinyl alcohol (PVA) with molecular weights of 9,000~10,000, 31,000~50,000, 89,000~98,000, and 130,000 were added and three concentrations of HNO₃ (0.1, 0.3, 0.5 molar ratio) were added to determine their effects on the particles. The crystal structure, composition, particle size and shape of the prepared γ-Al₂O₃ were confirmed through x-ray diffraction (XRD), x-ray fluorescence analyzer (XRF), particle size analyzer (PSA), and field emission scanning electron microscopy (FE-SEM). As a result, γ-Al₂O₃ with a purity of approximately 98.2% was synthesized, and the particle size decreased and the uniformity increased with increasing ratio of HNO₃ addition and PVA molecular weight. From these results, the particle size can be controlled during the manufacturing process of γ-Al₂O₃ by controlling the addition ratio of PVA and HNO₃.

• International Journal of Highway Engineering
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• v.6 no.2 s.20
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• pp.15-24
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• 2004

Oxidation causes increment of the quantity of large molecular size or LMS in asphalt and is a major reason for hardening of asphalt binder. An extended service life of pavement on a road is expected by reducing oxidation of binder. Oxidation of binder occurs during hot mixing with aggregates before placement on road and then during in-service after the asphalt pavement is constructed. Quantitative increase of LMS as result of aging after RTFO and PAV was analyzed based on the data from high-pressure gel-permeation chromatography (HP-GPC). Polymer modified asphalt (PMA) after RTFO procedure showed 20-30% increment in LMS and then after PAV procedure more than twice, although the percentage of increment was different according to asphalt brand and grade. The PMAs containing LDPE or SBS, which showed a great mechanical property improvement in previous studies, were selected for characterizing PMA aging In this study. Considerably reduced increment of LMS was observed from the PMA containing LDPE after RTFO and PAV procedures. The GPC result showing the binder with less LMS increment means that the asphalt while being mixed with LDPE was aged less during the aging treatment. The dispersed particle of LDPE in asphalt cement seems to disturb oxidative aging reaction and evaporation.

• Journal of Sericultural and Entomological Science
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• v.31 no.1
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• pp.37-44
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• 1989

The parasporal crystals of Bacillus thuringinsis subspecies kurstaki, dendrolimus, finitimus, aizawai and israelensis were compared by polyacrylamide electrophoresis, amino acid composition and immunological analysis. In the subspecies of kurstaki, dendrolimus, finitimus and aizawai, the molecular weights of main subusnits of crystal solubilized by alkaline solution were 1.3${\times}$105 and 6.5${\times}$104 while those of subsp. israelensis were 4${\times}$104 and 1,4${\times}$104. The degradation of lepidopteran toxic subspecies crystals by silkworm midgut protease showed 6.0-6.4${\times}$104 molecular weight and the pattern of degradation of subsp. israelensis crystals was similar to that of alkaline solution treatment. In the amino acid composition, aspartic acid in subsp. israelensis and glutiamic acid in the other four subspecies were the most abundant. The immunological characteristics of the crystals revealed that the antibody produced against the alkali-solubilized crystal protein of subsp. israelensis reacted with only its antigen, but the crystal antigens from the other four lepidopteran toxic subspecies did cross-react with each other as well as with their own homologous antisera.

• The Korean Journal of Cytopathology
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• v.7 no.1
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• pp.1-11
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• 1996

From the concepts of cellular pathology and of exfoliative cytology, as elucidated by Virchow and Papanicolaou respectively in the late 19th and early 20th century, have evolved the primary methods for the diagnosis of cancer today. From Papanicolaou's concept of exfoliative cytology developed fine needle aspiration biopsy in the early 1960's, this has become a major diagnostic procedure and has contributed to a significant reduction in open biopsies and, therefore, to medical cost-effectiveness immunobiochemical techniques provided us with a supplement to cancer diagnosis in the 1980's. The immunoperoxidase method, using monoclonal antibodies, is applied primarily as an ancillary measure to elucidate the nature of cancers The availability of specific monoclonal antibodies has greatly facilitated the identification of cell products or surface markers. For example, antibodies directed against intermediate filaments have proved to be of value in determining the histogenesis oi poorly differentiated neoplasms. Tumor markers may serve as biochemical indicators of the presence of a neoplasm. They can be detected In plasma and other body fluids. Their concentration can be applied as a diagnostic test, for monitoring the clinical course of known cancer, and as a screening measure to detect certain cancers in a population at risk. Flow cytometry is a useful tool for distinguishing several cell characteristics, such as the immunophenotype of leukemia-lymphoma cells, the DNA content of neoplastic cells, and cell proliferation rate. Molecular biologic techniques provided a giant step for the management of cancer patients encompassing diagnosis, prognostic evaluation, and therapy. Nucleic acid hybridization techniques are utilized as Southern, Northern, and dot blots and in situ hybridization. Molecular biology and its techniques may bring a blight new horizon for understanding cancer biology and in designing therapy on the basis of gene manipulation.