• Microbiology and Biotechnology Letters
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• v.33 no.1
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• pp.1-8
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• 2005

Since Anton van Leeuwen­hoek first observed a surface-associated multicellular structure of bacterial cells in the 17th century, it has been shown to exhibit an ability to form a biofilm by numerous bacterial species. The biofilm formation is composed of distinct developmental stages, which include an attachment/adhesion of a single cell, a proliferation toward monolayered coverage, a propagation to aggregated microcolony, a maturation to 3-dimensional structure, and subsequently a local degradation. Investigation to identify the essential factors for bacterial biofilm formation has been performed via classical genetic approaches as well as recently developed technologies. The initial stage requires bacterial motility provided by a flagellum, and outermembrane components for surface signal interaction. Type IV-pilus and autoaggregation factors, e.g., type I-fimbriae or Ag43, are necessary to reach the stages of monolayer and micro colony. The mature biofilm is equipped with extracellular polymeric matrix and internal water-filled channels. This complex architecture can be achieved by differential expressions of several hundred genes, among which the most studied are the genes encoding exopolysaccharide biosyntheses and quorum-sensing regulatory components. The status of our knowledge for the biofilms found in humans and natural ecosystems is discussed in this minireview.

• Proceedings of the KSAR Conference
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• 2003.06a
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• pp.18-18
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• 2003

In human, sudden infant death syndrome(SIDS) is synonyms for the sudden, unexpected and unexplained death of an infant. The incidence of SIDS has been estimated to be from 1 to 3%. Cloning has a relatively high rate of late abortion and early postnatal death, particularly when somatic cells are used as donors of nuclei and rates as high as 40 to 70% have been reported. However, the mechanisms for SIDS in cloned animals are not known yet. To date, few reports provide detailed information regarding phenotypic abnormality of cloned pigs. In this study, most of the cloned piglets were alive at term and readily recovered respiration. However, approximately 82% of male cloned piglets (81/22) died within a week after birth. Significant findings from histological examinations showed that 42% of somatic cloned male piglets died earlier than somatic cloned female piglets, most probably due to severe congestion of lung and liver or neutrophilic inflammation in brain, which indicates that unexpected phenotypes can appear as a result of somatic cell cloning. No anatomical defects in cloned female piglets were detected, but three of the piglets had died by diarrhea due to bacterial infection within 15 days after birth. Although most of male cloned piglets can be born normal in terms of gross anatomy, they develop phenotypic anomalies that include leydig cell hypoplasia and growth retardation post-delivery under adverse fetal environment and depigmentation of hair- and skin-color form puberty onset. This may provide a mechanism for development of multiple organ system failure in some cloned piglets. Th birth weights of male cloned pig in comparison with those of female cloned piglets are significantly reduced(0.8 vs 1.4kg) and showed longer gestational day(120 vs 114). In conclusion, brain meningitis and hepatopneumonic congestion are a major risk factor for SIDS and such pregnancy in cloned animals requires close and intensive antenatal monitoring.

• Journal of Microbiology and Biotechnology
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• v.18 no.8
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• pp.1393-1400
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• 2008

Recent study has demonstrated an increasing prevalence of food allergy in Korean children. Specific probiotic bacteria may promote potentially anti-allergenic processes through induction of Th1-type immunity and enhance the regulatory lymphocyte. This study investigated whether orally administrated probiotics could suppress allergic responses in an ovalbumin (OVA)-induced allergy mouse model. Thus, female C3H/HeJ mice were orally sensitized with OVA and cholera toxin for 4 weeks. Lactobacillus acidophilus AD031, Bifidobacterium lactis AD011, and L. acidophilus AD031 plus B. lactis AD011 were fed to mice from 2 weeks before the sensitization. The OVA-induced mice that were not treated with probiotics had significantly increased serum levels of OVA-specific IgE and IgG1, and OVA-specific IgA in feces. However, the mice treated with probiotics suppressed production of the OVA-specific IgE, IgG1, and IgA. The level of IL-4 was significantly lower, and the levels of INF-$\gamma$ and IL-10 were significantly higher in the mice treated with probiotics than that in the non-treated mice. The groups treated with probiotics had decreased levels of degranulated mast cells, eosinophil granules, and tail scabs. These results indicate that L. acidophilus AD031 and B. lactis AD011 might be useful for the prevention of allergy.

• Microbiology and Biotechnology Letters
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• v.14 no.6
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• pp.455-460
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• 1986

Dane particle was prepared from the plasma of chronic HBsAg carrier with high levels of HBsAg activity. DNA extracted front Dane particle core after a DNA polymerase reaction with $\alpha$-($^{32}$P) dNTP, was identified as HBV DNA by liquid scintillation counter and agarose gel electrophoresis-G.M. counting. To produce Hepatitis B surface antigen for use as a vaccine against Hepatitis B virus infection, yeast strains harboring recombinant plasmid with Apase promoter was used. Recombinant plasmid was construced from pHBV 130 and pAN 82, transformed into E coli, and then transferred into yeast strains. HBsAg was produced by derepression in Burkholder minimal medium with controlled inorganic phosphate concentration. The kinetics of HBsAg production was also investigated. Total HBsAg activity increased rapidly between 3 and 6 hours after transfer to phosphate-free medium and reached a maximum at around 9th hour. The transfer into phosphate-free medium after 6 hours in high phosphate cell growth medium gave maximum activity.

• Archives of Pharmacal Research
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• v.20 no.1
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• pp.17-23
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• 1997

A saline suspension of Lumbricus rubellus earthworm powder (EWP) was administered to rats (1 g/kg/day) orally for 15 days to evaluate an oral effectiveness for thrombotic disorders. Blood was drawn at 2-day interval after the administration. Several parameters for antithrombotic, anticoagulant and fibrinolytic activities were measured, including platelet aggregation, clotting time, plasmin activity and the levels of FDP (fibrin/fibrinogen degradation products), D-dimer, and t-PA antigen. It did not affect platelet aggregation induced by ADP and collagen but anticoagulant activity (aPTT and TT) was gradually increased to two-folds for the first 5 days of administration and back to normal. Fibrinolytic activity of euglobulin fraction was highest on the 11 th day after the administration. The level of FDP was elevated to be comparable to the positve control$ (5-10 {\mu}g/ml)$ after 9-day treatment. Oral administration of the EWP could also reduce the formation of venous thrombus induced with viper venom. Complete blood count (CBC) profiles were within normal ranges except for a slight increase in white blood cells after the oral administration for 15 days. These results suggested that the EWP may be valuable for the prevention and/or treatment of thrombotic diseases.

• Food Science and Preservation
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• v.16 no.2
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• pp.253-258
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• 2009

This study investigated the effects of mycelium and culture supernatant of Cordyceps ochraceostromat(Co) on air way hyper-responsiveness, pulmonary immune cell infiltration, and Th2 cytokine expression in animal models of atopy and asthma. After ConA(+/-) activation of mouse primary spleen cells, decreased IL-4 and IL-13 cytokine production were seen in the presence of Co mycelium extracts and culture supernatant. The asthma model involved mice sensitized to ovalbumin by i.p. injection treatment; Co mycelium extract was also injected. The atopy model was the dinitrofenylbenzene-treated mouse ear. Ear thicken ing induced by DNFB was decreased by Co mycelium extract, and the extract also inhibited lung cell infiltration in ovalbumin-induced asthmatic mice. The results thus indicated that the Co mycelial extract reduced the undesirable immune responses seen in asthma and atopy.

• Journal of Periodontal and Implant Science
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• v.34 no.2
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• pp.317-332
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• 2004

Osteoblasts from alveolar bone may have an important role in the bone regeneration for periodontium, but their culture and characterization are not determined yet. The purpose of this study was to investigate the biological characteristics of primary explant cultured osteoblasts(PECO) from alveolar bone. Osteoblasts were isolated and cultured from alveolar socket of extracted tooth in children. To compare the characteristics, osteoblasts and gingival fibroblasts were cultured with DMEM at $37^{\circ}C$, 5% $CO_2$, l00% humidity incubator, and human fetal osteoblasts cell line(hFOB1) were cultured with DMEM at $34^{\circ}C$, 5%, $CO_2$ 100% humidity incubator. To characterize the isolated bone cells, morphologic change, cell proliferation and differentiation were measured. Morphology of PECO was small round body or cuboidal shape on inverted microscope and was similar with hFOB1. PECO became polygonal shape with stellate and had an amorphous shape at 9th passage in culture. PECO had significantly higher activity than that of gingival fibroblasts and hFOB1 in alkaline phosphatase activity. The expression of osteocalcin and bone sialoprotein in PECO was notably increased when compared with hFOB1 and gingival fibroblasts. These result indicated that PECO from alveolar bone in children has an obvious characteristics of osteoblast, maybe applied for the regeneration of bone.

• Journal of Periodontal and Implant Science
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• v.25 no.2
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• pp.357-371
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• 1995

The purpose of this study was to observe the effect of $TGF-{\beta}1$ on the regeneration of bone in guided bone regeneration. Four adult dogs aged 12 to 24 months were used in this study. Experimental bone defects were created surgically with surgical bur and chisel on the 3th. premolars. In experimental group, bone defect were grafted with DFDB and $TGF-{\beta}1$. In control groups, bone defects were grafted with only DFDB. At 1,2,3 and 4 weeks, dogs were serially sacrificed and specimens were prepared with Hematoxylin-Eosin stain and Goldner's stain for light microsopic evaluation. The results of this study were as follows: 1. The infiltration of inflammatory cells was prominent in control groups at 1, 2 and 3 weeks. 2. The lining of osteoblast was observed at 2 weeks in control group, but at 1 week in experimental group. 3. In both groups, osteoid was formed at 2 weeks. In control groups, osteoid was fromed on only bone surface. but in experimental groups, osteoid were formed on both bone & DFDB surfaces. 4. In only experimental groups, The fusion of new bone & DFDB was only observed at 3 weeks. and the fusion of new bone & DFDG was more prominent at 4 weeks. But in control groups, No fusion of new bone& DFDB was oberved at 3 and 4weeks. From the above result, the $TGF-{\beta}1$ was effective in bone formation and increased inductive effect of DFDB in guided bone regeneration technique. Inductive effect of DFDB was increased with $TGF-{\beta}1$.

• Molecules and Cells
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• v.37 no.2
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• pp.172-177
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• 2014

A glycosyltransferase, YjiC, from Bacillus licheniformis has been used for the modification of the commercially available isoflavonoids genistein, daidzein, biochanin A and formononetin. The in vitro glycosylation reaction, using UDP-${\alpha}$-D-glucose as a donor for the glucose moiety and aforementioned four acceptor molecules, showed the prominent glycosylation at 4' and 7 hydroxyl groups, but not at the $5^{th}$ hydroxyl group of the A-ring, resulting in the production of genistein 4'-O-${\beta}$-D-glucoside, genistein 7-O-${\beta}$-D-glucoside (genistin), genistein 4',7-O-${\beta}$-D-diglucoside, biochanin A-7-O-${\beta}$-D-glucoside (sissotrin), daidzein 4'-O-${\beta}$-D-glucoside, daidzein 7-O-${\beta}$-D-glucoside (daidzin), daidzein 4', 7-O-${\beta}$-D-diglucoside, and formononetin 7-O-${\beta}$-D-glucoside (ononin). The structures of all the products were elucidated using high performance liquid chromatography-photo diode array and high resolution quadrupole time-of-flight electrospray ionization mass spectrometry (HR QTOF-ESI/MS) analysis, and were compared with commercially available standard compounds. Significantly higher bioconversion rates of all four isoflavonoids was observed in both in vitro as well as in vivo bioconversion reactions. The in vivo fermentation of the isoflavonoids by applying engineered E. coli $BL21(DE3)/{\Delta}pgi{\Delta}zwf{\Delta}ushA$ overexpressing phosphoglucomutase (pgm) and glucose 1-phosphate uridyltransferase (galU), along with YjiC, found more than 60% average conversion of $200{\mu}M$ of supplemented isoflavonoids, without any additional UDP-${\alpha}$-D-glucose added in fermentation medium, which could be very beneficial to large scale industrial production of isoflavonoid glucosides.

• ALGAE
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• v.27 no.3
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• pp.205-213
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• 2012

The thermostability of antioxidant activity of dieckol, a phlorotannin isolated from brown seaweed Ecklonia cava was investigated. The thermostable antioxidant properties of dieckol were evaluated at 30, 60, and $90^{\circ}C$ for 7 days using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and hydroxyl radical scavenging activities, and comparing its performance to that of ascorbic acid. The intracellular reactive oxygen species (ROS) scavenging activity and apoptotic body formation were investigated using DCF-DA assay and nuclear staining with Hoechst 33342, propidium iodide and flow cytometry. Dieckol treated at different temperatures during 7 days showed stable scavenging activities on towards DPPH and hydroxyl radicals. In addition, dieckol showed a stable protective effect against $H_2O_2$-induced apoptotic body formation in Vero cells. On the other hand, the radical scavenging activities and intracellular ROS scavenging activities of ascorbic acid, used as a positive control, were significantly decreased at $60^{\circ}C$ and $90^{\circ}C$ from on the 4th day and 3rd days, respectively. In conclusion, the results indicated that food grade antioxidant extracts containing dieckol derived from E. cava remain a stable during the temperatures encountered during the processing of food and cosmetics.