• Journal of Food Hygiene and Safety
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• v.11 no.4
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• pp.315-321
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• 1996

Various antimicrobial drug screen tests have been used in order to ensure food safety. However, the conventional screen tests, the Swab Test on Premises(STOP, USA), the Calf Antibiotic and Sulfa Test(CAST, USA) and the European Economic Community 4-plate Test(FPT, EU) are not sufficiently rapid or sensitive enough to detect low levels of sulfa drugs in meat. We developed a new screen test kit for the determination of the antimicrobial residues in meat called the Bacillus megaterium Disk Assay(BmDA). A comparison of BmDA with the older screen tests showed BmDA was as good as the older ones with several advantages. The new test kit is faster-it can be read in 4∼6 hours instead of 16∼18 hours. Moreover, BmDA can discriminate sulfa drugs from other antimicrobial drugs because p-aminobenzoic acid countacts the inhibiting action of sulfa drugs. Minimum detectable levels of sulfa drugs were significantly improved at the lever of 0.025*0.1 pp, compared with the level of 1.0 ppm in FPT. A comparison of BmDA with the older screen tests in HPLC confirmed meat samples exceeded the Korean tolerance value of 0.1 ppm showed BmDA was the most sensitive in the microbiological screen tests. As the microbiological screen tests have already known, a person familiar with simple laboratory techniques should have no difficulty in using it to detect antimicrobial residues in meat. This would be a simple, economic method of antimicrobial residues detection which might be succesfully used by many laboratories.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.9
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• pp.5489-5494
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• 2013

In the current study we aimed to show the common YMDD motif mutations in viral polymerase gene in chronic hepatitis B patients during lamivudine and adefovir therapy. Forty-one serum samples obtained from chronic hepatitis B patients (24 male, 17 female; age range: 34-68 years) were included in the study. HBV-DNA was extracted from the peripheral blood of the patients using an extraction kit (Invisorb, Instant Spin DNA/RNA Virus Mini Kit, Germany). A line probe assay and direct sequencing analyses (INNO-LIPA HBV DR v2; INNOGENETICS N.V, Ghent, Belgium) were applied to determine target mutations of the viral polymerase gene in positive HBV-DNA samples. A total of 41 mutations located in 21 different codons were detected in the current results. In 17 (41.5%) patients various point mutations were detected leading to lamivudin, adefovir and/or combined drug resistance. Wild polymerase gene profiles were detected in 24 (58.5%) HBV positive patients of the current cohort. Eight of the 17 samples (19.5%) having rtM204V/I/A missense transition and/or transversion point mutations and resistance to lamivudin. Six of the the mutated samples (14.6%) having rtL180M missense transversion mutation and resistance to combined adefovir and lamivudin. Three of the mutated samples (7.5%) having rtG215H by the double base substituation and resistance to adefovir. Three of the mutated samples (7.5%) having codon rtL181W due to the missense transversion point mutations and showed resistance to combined adefovir and lamivudin. Unreported novel point mutations were detected in the different codons of polymerase gene region in the current HBV positive cohort fromTurkish population. The current results provide evidence that rtL180M and rtM204V/I/A mutations of HBV-DNA may be associated with a poor antiviral response and HBV chronicity during conventional therapy in Turkish patients.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.4
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• pp.1005-1009
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• 2013

Using DNA sequencing method, we analyzed mutations of rpoB (RNA polymerase beta subunit) rifampin-resistant Mycobaterium tuberculosis strains which were identified by conventional test at Masan National Hospital and The Korean Institute of Tuberculosis. Though it has been reported different mutations of rpoB region of rifampin-resistant M. tuberculosis strains in the south of Korea, it is not confirmed whether these mutations of rpoB region actually express rifampin resistance through experiment. We confirmed experimentally these mutations of rpoB region of M. tuberculosis strains induced rifampin-resistance through ampified rpoB by polymerase chain reaction (PCR) and cloning of mutant rpoB into rifampin sensitive-M. tuberculosis strain.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.39 no.2
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• pp.78-84
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• 2006

A high performance liquid chromatography assay method for spiramycin in fish muscle was developed. The developed method was evaluated and validated by monitoring spiramycin in olive flounder (Paralichthys olivaceus), black rock fish (Sebastes schlegeli) and in live conger eel (Anguilla japonica) in fish farms and distribution centers. Using the developed method, the recovery rate was up to 82.4-88.8%, which was higher than that of conventional methods (77.6-87.1%). In particular, the proposed sample treatment protocol was suitable for use with fish samples to remove low molecular weight materials and pigments that could interfere an accurate analysis. The prepared stock solution was very stable, and it remained chemically stable for 5 weeks at $4^{\circ}C$. The performance limit of the developed method for spiramycin acid in fish muscle was 0.05 ppm. One hundred thirty-four fish samples including olive flounder, black rock fish and live conger eel were analyzed to evaluate the overall efficiency of the modified method and to monitor the actual condition of spiramycin usage in fish farms. Olive flounder and black rock fish were collected from fish farms in coastal areas of Korea, and live conger eels were purchased from a fish market in the Busan area from September 2001 to March 2002. According to the overall performance of the developed method, it was considered suitable for the monitoring of spiramycin in fish muscle. The suggested method of analysis for spiramycin in fish muscle is registered in the Korean Official Methods of Food Analysis and is currently tieing utilized for fishery products inspection by the Korea Food and Drug Administration and the National Fisheries Products Quality Inspection Service.

• Natural Product Sciences
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• v.21 no.3
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• pp.162-169
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• 2015

Hamamelis japonica (Hamamelidaceae), widely known as Japanese witch hazel, is a deciduous flowering shrub that produces compact clumps of yellow or orange-red flowers with long and thin petals. As a part of our ongoing search for phenolic constituents from this plant, eleven phenolic constituents including six flavonol glycosides, a chalcone glycoside, two coumaroyl flavonol glycosides and two galloylated compounds were isolated from the flowers. Their structures were elucidated as methyl gallate (1), myricitrin (2), hyperoside (3), isoquercitrin (4), quercitrin (5), spiraeoside (6), kaempferol 4'-O-β-glucopyranoside (7), chalcononaringenin 2'-O-β-glucopyranoside (8), trans-tiliroside (9), cis-tiliroside (10), and pentagalloyl-O-β-D-glucose (11), respectively. These structures of the compounds were identified on the basis of spectroscopic studies including the on-line LCNMR-MS and conventional NMR techniques. Particularly, directly coupled LC-NMR-MS afforded sufficient structural information rapidly to identify three flavonol glycosides (2 - 4) with the same molecular weight in an extract of Hamamelis japonica flowers without laborious fractionation and purification step. Cytotoxic effects of all the isolated phenolic compounds were evaluated on HCT116 human colon cancer cells, and pentagalloyl-O-β-D-glucose (11) was found to be significantly potent in inhibiting cancer cell growth.

• Korean Journal of Veterinary Research
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• v.47 no.1
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• pp.33-41
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• 2007

Streptococcus spp. comprising Streptococcus (S.) uberis S. dysgalactiae strains is major causeof bovine mastitis from particularly well-managed or low somatic cell count herds that have successfullycontrolled contagious pathogens. In this study, antimicrobial susceptibility and genetic characteristics of S.uberis isolated from clinical or subclinical mastitis milk at 2003 were investigated. Eighty seven isolatesof Streptococus spp. were identified by the conventional biochemical methods. The antimicrobialsusceptibility by disk diffusion method was determined for 46 S. uberis, 11 S. bovis, 10 S. oralis, 6 S.uberis and 14 other Streptococcus spp.. Overall, the tested strains were susceptible to tetracycline (11.5%),amikacin (14.9%), streptomycin (16.1%), neomycin (26.4%), kanamycin (35.6%), gentamicin (65.2%),oxacillin (70.1%), ampicillin (75.9%), chloramphenicol (78.2%), and cephalothin (97.7%). Additionally, S.uberis strains were susceptible to pencillin G (97.8%), but resistant to erythromycin (76.0%) by minimalinhibitory concentration test. The multiple-drug resistance rate of isolated bacteria to 4 more thanamplification fingerprinting patterns amplifed with primer 8.6d showed that 3 to 8 number of distinguishableDNA fragments ranged from 180 bp to 1,20 bp. Thirty seven isolates of S. uberis strains were subtypedinto 8 distinct patterns. Each subtype revealed a typical pattern of antimicrobial susceptibilities. Thesefindings demonstrate that S. uberis isolates were mastitis pathogens of diverse serotypes, and oftenencountered the diverse resistant patterns.

• Journal of Food Hygiene and Safety
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• v.8 no.4
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• pp.215-223
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• 1993

Chloramphenicol (CAP) is a very effective broad-spectrum antibiotic which had been widely used in animal production. However, the drug is not approved in many countries for use in food-producing animals because of its potential toxicity and the possibility of residues in food products. In this study, a modified microbiological assay was developed for the sensitive detection of CAP residues in meat and milk. The method was characterized by the extraction of CAP with ethyl acetate, addition of $0.15\;\mu\textrm{g}$ oxytetracycline/ml in the phosphate buffer diluent (pH 6.0), a luteus ATCC 9341. The lowest levels of CAP detected in muscle tissues and milk were $0.025\;\mu\textrm{g}/ml\;and\;0.05\;\mu\textrm{g}/g$, respectively. Recovery rates free CAP from milk were 68.5%, from bovine muscle 65.1%, from swine muscle 63.8%, and from chicken muscle 59.4%, respectively, and the coefficients of variation were 1.8~15.1%. The results showed that the detection limits of CAP residues in animal products could significantly be improved by the modified microbiological assay than the conventional ones.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.38 no.6
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• pp.379-384
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• 2005

A high-performance liquid chromatography assay method for oxolinic acid in fish products was developed, evaluated and validated through the monitoring of oxolinic acid based on farming and distribution. The recovery rate of the developed method was $102.3-106.7\%$ as compared to conventional methods. The stock solution was stable for 3 weeks under refrigerated condition at $4^{\circ}C$ The performance limit was evaluated as 0.01ppm of oxolinic acid in fish muscle. 478 fish samples such as olive flounder, genuine porgy, common sea bass and black rock fish collected from fish farms in the coastal area from September 2001 to October 2004 were analyzed to evaluate overall efficiency of the modified method and to monitor the actual condition of oxolinic acid usage in fish farm. According to the monitoring results, the modified method was suitable for analysis of oxolinic acid in fish muscle and oxolinic acid might be used in a small portion of fish farms. The suggested analysis method of oxolinic acid was registered in the Korean Official Methods of Food Analysis and is being utilized for fishery products by the Korea Food and Drug Adminstration and the National Fisheries Products Quality Inspection Service.

• 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.

• The Korea Journal of Herbology
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• v.31 no.5
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• pp.79-84
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• 2016

Objective : Nypa fruticans Wurmb. Fruit (NF) has been used as a conventional medicine to treat inflammatory peridontal diseases in Myanmar and Eastern Asia. However, the anti-inflammatory effect of NF aqueous extract on lipopolysaccharide (LPS)-induced inflammatory responses was not well-investigated. Therefore, this study was aimed to investigate the anti-inflammatory effect of NF on LPS-induced inflammatory responses on RAW 264.7 cells.Methods : To induce inflammation on the macrophage cell line, RAW 264.7 cells were treated with 500 ng/mL of LPS. Water extracts of NF was treated 1 h prior to treatment of LPS. Cell viability was measured by MTT assay. Production of nitrite was measured with Griess assay and pro-inflammatory cytokines such as interleukine (IL)-1β and IL-6, and tumor necrosis factor (TNF)-α was measured by enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (PCR). In addition, we examined the inhibitory mechanisms of NF by western blot and immunocytochemistry.Result : Water Extract from NF itself did not have any cytotoxic effect at the concentration of 200 ㎍/ml in RAW 264.7 cells. Treatment of NF inhibited the production of nitrite, and pro-inflammatory cytokines inlcuding IL-1β, IL-6 and TNF-α in a dose dependant. In addition, NF treatment inhibited the LPS-induced activation and translocation of nuclear factor (NF)-κB.Conclusion : In summary, our result suggest that treatment of NF could reduce the LPS-induced inflammatory responses via deactivation of NF-κB. This study could suggest that NF could be a beneficial drug or agent to prevent inflammation.