• Journal of fish pathology
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• v.3 no.1
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• pp.11-19
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• 1990

Yellow tail (Seriola quinqueradiata) infected by Pasteurella piscicida have been occurred to mass mortality without showing apparent surface lesions in cage culture farms. In this case, it is necessary to consider countermeasure by rapid diagnosis of infected fish. The purpose of the present study was to investigate usefulness of the direct fluorescent antibody technique(FAT) for rapid diagnosis of pseudotuberclosis of cultured yellowtail caused by P. piscicida. Antibody produced by inoculating rabbit with formalin killed pseudotuberclosis bacteria antigen(strain KNP-2). Immunoglobulin-G(IgG) was purified from antisera by DEAE-cellulose column chromatography and conjugate with fluorescein isothiocyanate. Fluorescein-labeled antisera was purified by sephadex G-25 gel column chromatography. The fluorescein/protein molar ratio of labeled antisera was determined as 8.8-9.5. Diagnosis of cultured yellowtail was examined in cage culture farms which located in Tongyung, kyungnam from July to October 1990. The causative bacteria of pseudotuberclosis could be detected within two hours after the specimens were transferred to the laboratory for FAT, and it showed that FAT could be adapted as a rapid and accurate diagnostic method of pseudotuberclosis in yellowtail.

• Analytical Science and Technology
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• v.8 no.3
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• pp.221-227
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• 1995

The fiber optic fluorosensor that shows a specific selectivity for calcium ion is studied. This sensor employs protein Calmodulin(CaM) which forms a fluorescent chelate with $Ca^{2+}$. A dialysis membrane is used to entrap a fluorescein isothiocyanate-labeled CaM solution at the common end of a bifurcated fiber optic bundle. The sensing mechanism of this sensor is based on the shifts in the fluorescence spectrum of metal-calmodulin complexes which FCaM forms a chelate with $Ca^{2+}$. Upon binding with $Ca^{2+}$, CaM undergoes a conformational change which induces a change in the fluorescence of FCaM. This change in fluorescence signal which is measured by photomultiflier tube is related to the concentration of $Ca^{2+}$ for calibration curve. Detection limit for $Ca^{2+}$ and the interference effects by $Mg^{2+}$, $Eu^{3+}$ and $La^{3+}$ for this sensor are studied. Response time and life time for this fluorosensor are also investigated.

• KSBB Journal
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• v.22 no.4
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• pp.260-264
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• 2007

Peptides are frequently studied as candidates for new drug development. Recently, synthesized peptide library is screened for a certain functionality on a microarray biochip format. In this study, in order to replace the conventional cellulose membrane with glass for a microarray chip substrate for peptide library screening, we modified the glass surface from amines to thiols and covalently immobilized the peptides. Using trypsin-FITC (fluorescein isothiocyanate) conjugate that could specifically bind to a trypsin binding domain consisting of a 7-amino acid peptide, we checked the degree of surface modification. Because of the relatively lower hydrophilicity and reduced surface roughness, the conjugation reaction to the glass required a longer reaction time and a higher temperature. It took approximately 12 hr for the reaction to be completed. From the fluorescence signal intensity, we could differentiate between the target and the control peptides. This difference was confirmed by a separate experiment using QCM. Furthermore, a smaller volume and higher concentration of a spot showed a higher fluorescence intensity. These data would provide the basic conditions for the development of microarray peptide biochips.

• Animal cells and systems
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• v.15 no.3
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• pp.211-218
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• 2011

Fragmentation in human pre-implantation embryos has been suggested as the process of apoptosis. We have previously demonstrated a direct relationship between the increased reactive oxygen species (ROS) and apoptosis in human pre-implantation embryos. ROS is known to suppress the function of mitochondria in which steroidogenic acute regulatory protein (StAR) and peripheral-type benzodiazepine receptor (PBR) are presented. Therefore, the purpose of this study was to examine the expression of StAR and PBR in human pre-implantation embryos and to evaluate whether reduction of these proteins is associated with apoptosis. Apoptosis was detected by annexin V-fluorescein isothiocyanate (FITC) and mitochondrial membrane potential was measured by 5,5',6,6'-tetrachloro-1,1',3,3'-tetraethyl-benzimidazolyl-carbocyanine iodide (JC-1). Immunofluorescence staining and Western blotting were applied to examine the expression of StAR and PBR in the embryos. Lipid droplets in the embryos were stained with Oil Red O. The fragmented pre-implantation embryos were stained with annexin V-FITC, but not the normal ones. The mitochondria with active membrane potential were present less in the fragmented embryos compared with the non-fragmented embryos. We also confirmed that both StAR and PBR were expressed in the embryos and their expression levels were lower in the fragmented ones. In addition, the number and size of lipid droplets were increased in the fragmented embryos. The present study provides evidence that reduction of StAR and PBR in human pre-implantation embryos is associated with an increase in the lipid droplets leading to apoptosis.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.999-1005
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• 1997

The consistant appearance of coliforms in fermenting kimchi was examined and measures of removing coliforms early in the fermentation were investigated. Allyl isothiocyanate $({\geq}50\;ppm)$, horseradish powder $({\geq}0.4%)$, and garlic juice $({\geq}2.0%)$ were effective in removal of coliforms early in kimchi fermentation. However, mustard powder and methyl methanethiosulfonate were not effective. Nisin, known as a promising agent for the prevention of kimchi over-acidification, allowed coliforms to survive in kimchi longer with only marginal extention of edible period. Individual kimchi ingredients such as Chinese cabbage, garlic, red pepper powder, ginger and green onion were all found to contain coliforms. Coliforms were not detected from garlics sold unpeeled and commercially prepared red pepper powder.

• Journal of Microbiology and Biotechnology
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• v.16 no.9
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• pp.1369-1376
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• 2006

Self-organized nanogels were prepared from pullulan/biotin conjugates (PU/Bio) for the development of an effective anticancer drug delivery system. The degree of biotin substitution was 11, 19, and 24 biotin groups per 100 anhydroglucose units of pullulan. The physicochemical properties of the nanogels (PU/Bio1, 2 and 3) in aqueous media were characterized by dynamic light scattering, transmission electron microscopy, and fluorescence spectroscopy. The mean diameter of all the samples was less than 300 nm with a unimodal size distribution. The critical aggregation concentrations (CACs) of the nanoparticles in distilled water were $2.8{\times}10^{-2},\;1.6{\times}10^{-2}$, and $0.7{\times}10^{-2}mg/ml$ for the PU/Bio1, 2, and 3, respectively. The aggregation behavior of the nanogels indicated that biotin can perform as a hydrophobic moiety. To observe the specific interaction with a hepatic carcinoma cell line (HepG2), the conjugates were labeled with rhodamine B isothiocyanate (RITC) and their intensities measured using a fluorescence microplate reader. The HepG2 cells treated with the fluorescence-labeled PU/Bio nanoparticles were strongly luminated compared with the control (pullulan). Confocal laser microscopy also confirmed internalization of the PU/Bio nanogels into the cancer cells. Such results demonstrated that the biotin in the conjugate acted as both a hydrophobic moiety for self-assembly and a tumor-targeting moiety for specific interaction with tumor cells. Consequently, PU/Bio nanogels would appear to be a useful drug carrier for the treatment of liver cancer.

• Clean Technology
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• v.20 no.2
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• pp.141-145
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• 2014

In this study, we studied optical properties on the layer-by-layer (LbL) assemblies consisting of Au nanorods and organic dyes. For this purpose, poly (allylamine hydrochloride), PAH and poly (styrene sulfonate), PSS were selected as ionic polymers and rhodamine B isothiocyanate (RB) was utilized as an organic dye based on its spectral overlap with plasmon band of Au nanorods. In the view point of assembling methods, RB was covalently attached to PAH, then, LbL structure of Au [PSS/PAH]2/PSS/PAH-RB was prepared by sequential coating of PAH, PSS, PAH-RB on Au nanorods. Since the prepared LbL assembly exhibits both plasmonic and fluorescent properties, we studied the mutual nanorod-dye properties by dissolving Au nanorods.

• The Journal of Advanced Prosthodontics
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• v.5 no.2
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• pp.84-91
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• 2013

PURPOSE. The aim of this study was to evaluate the stability of arginine-glycine-aspartic acid (RGD) peptide coatings on implants by measuring the amount of peptide remaining after installation. MATERIALS AND METHODS. Fluorescent isothiocyanate (FITC)-fixed RGD peptide was coated onto anodized titanium implants (width 4 mm, length 10 mm) using a physical adsorption method (P) or a chemical grafting method (C). Solid Rigid Polyurethane Foam (SRPF) was classified as either hard bone (H) or soft bone (S) according to its density. Two pieces of artificial bone were fixed in a customized jig, and coated implants were installed at the center of the boundary between two pieces of artificial bone. The test groups were classified as: P-H, P-S, C-H, or C-S. After each installation, implants were removed from the SRPF, and the residual amounts and rates of RGD peptide in implants were measured by fluorescence spectrometry. The Kruskal-Wallis test was used for the statistical analysis (${\alpha}$=0.05). RESULTS. Peptide-coating was identified by fluorescence microscopy and XPS. Total coating amount was higher for physical adsorption than chemical grafting. The residual rate of peptide was significantly larger in the P-S group than in the other three groups (P<.05). CONCLUSION. The result of this study suggests that coating doses depend on coating method. Residual amounts of RGD peptide were greater for the physical adsorption method than the chemical grafting method.

• Korean Journal of Food Science and Technology
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• v.20 no.2
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• pp.194-199
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• 1988

The objective of this study was to investigate the technical feasibility of producing toxicant-free rapeseed by germination. To this end, rapeseed(Brassica napus L.)was germinated at $25^{\circ}C$ for 120 hours, and the chemical compositions-glucosinolates and free sugers-were determinated in every 24 hours during germination. The amount of glucosinolates in rapeseed measured by UV method was very close to that measured by GLC method. The glucosinolates were considerably abundant in rapeseed before germination, and the total content was found to be 13.6 mg/g. Rapeseed showed the lowest glucosinolate content in 72 hours during germination, and it gradually increased glucosinolate content from 96 hours. Free suger content in rapeseed before germination was as follows : 3.03 mg/g of fructose, 2.97 mg/g of glucose and 5.63 mg/g of sucrose. Raffinose and stachyose were not detected, and in general free sugars were gradually decreased during germination. However, sucrose was increased in the early period of gremination and decreased in the later period.

• Korean Chemical Engineering Research
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• v.48 no.2
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• pp.178-184
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• 2010

The aim of this work is the fabrication of polyelectrolyte microcapsules composed of biocompatible polymers such as chitosan, heparin and alginate, to encapsulate the fluorescein isothiocyanate(FITC)-albumin, and to investigate the protein release behavior therefrom. Polyelectrolyte capsules with 4-layer structures could be prepared with biocompatible materials by oppositely charged adsorption using melamin-foramide as a template. Transmission electron microscope(TEM), scanning electron microscope(SEM) and optical microscope confirmed hollow capsule structures. Protein release before and after encapsulation was monitored with a UV-Vis spectrometer. Microcapsules have different behaviors depending on the kind of polyelectrolyte polymers, chitosan-heparin capsules or chitosan-alginate capsules. In conclusion, the polyelectrolyte multilayer shells can be switched between an open and closed state by means of tuning the pH value.