• Food Science and Preservation
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• v.20 no.5
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• pp.684-690
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• 2013

The antioxidant and photoprotective effects of various extracts from the roots of Rumex crispus L. were evaluated. The concentrations ($IC_{50}$) of various extracts required to exert a 50% reducing effect on a DPPH radical were found to be 0.005~0.093 mg/mL. The ethyl acetate extract showed a more remarkable effect than the positive control ascorbic acid. The concentrations ($QC_{50}$) of the butanol and ethyl acetate extracts required to exert a 50% reducing effect on the singlet oxygen $^1O_2$ were found to be 0.464 and 0.365 mg/mL, respectively. Both extracts were also found to protect the in vitro biological system from the detrimental effect of a singlet oxygen $^1O_2$ on type II photosensitization in E. coli and genomic DNA. Among all the tested extracts, the ethyl acetate and butanol extracts contained higher amounts of total phenolic contents. The results suggest that our study may contribute to the development of new bioactive products with potential applications to the reduction of photo-produced oxidative stress involving reactive oxygen species in living organisms.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.1
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• pp.32-37
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• 2009

This study was carried out to gather basic data on the restoration and extent of Don tea (a coin-shaped tea), the traditional tea of Korea. We examined the physicochemical components and anti-microbial activity of Don tea extracts at 0, 5 and 10 months. The Hunter value $L^*$, of Don tea extracts which were matured for 10 months decreased from 7.01 to 4.97 compared to that when the extracts were first manufactured. However, the $b^*$ value increased from 0.09 to 2.67. There were higher contents of inorganic matter in Don tea extracts following manufacture in the order of K (14.12 mg/100 mL), Mg (0.94 mg/100 mL), P (0.88 mg/100 mL), Ca (0.16 mg/100 mL) and Mn (0.16 mg/100 mL). Classified catechins contents were found in the order of C (19.97 mg/100 mL), EGC (9.30 mg/100 mL), ECG (9.02 mg/100 mL), GCG (8.50 mg/100 mL), GC (7.61 mg/100 mL) and CG (5.63 mg/100 mL). The longer the maturation period of the Don tea extracts, the lower the contents of inorganic matter and catechins. However, this did not apply to the total phenol contents, particularly in the phenol contents of Don tea extracts matured for 10 months which increased by 93.82 mg/l00 mL. Don tea extracts which were matured for longer periods showed higher anti-microbial activities against Bacillus subtilis and Streptococcus mutans. However, there were lower activities against Staphylococcus aureus, Escherichia coli and Salmonella enteritidis. Consequently, it was concluded that a shorter maturation period was required for the effective utilization of the inorganic matter, the catechins and the gram-negative bacteria in the Don tea extracts. However, a longer maturation period of 10 months was found to effectively utilize the total phenol compound contents and the gram-positive bacteria.

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.62-72
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• 2002

This study has investigated the biosynthesis and function of the heavy metal binding peptides, the phytochelatins, in plants. PCs are synthesised enzymatically from glutathione by the enzyme PC synthase in the presence of heavy metal ions. Using Arabidopsis thaliana as a model organism cadmium-sensitive, phytochelatin-deficient mutants have been isolated and characterised in previous studies. The cadl mutants have wildtype levels of glutathione, are PC deficient and lack PC synthase activity. Thus, the CADl gene has been proposed to encode PC synthase. The CADl gene was isolated by a positional cloning strategy The gene was mapped and a candidate identified. Each of four cadl mutants had a single base pair change in the candidate gene and the cadmium-sensitive, cadl phenotype was complemented by the candidate gene. This demonstrated the CADl gene had been cloned. A homologous gene in the fission yeast, Schizosaccharomyces pombe was identified through database searches. A targeted-deletion mutation of this gene was constructed and the mutant, like cadl mutants of Arabidopsis, was cadmium-sensitive and PC-deficient. A comparison of the redicted amino acid sequences reveals a highly conserved N-terminal region Presumed to be the catalytic domain and a variable C-terminal region containing multiple Cys residues proposed to be involved in activation of the enzyme by metal ions. Similar genes were also identified in animal species. The Arabidopsis CADl/AtPCSl and S. pombe SpbPCS genes were expressed in E. coli and were shown to be sufficient for glutathione-dependent, heavy metal activate PC synthesis in vitro, thus demonstrating these genes encode PC synthase enzymes. Using RT-PCR, AtPCSl expression appeared to be independent of Cd exposure. However, at higher levels of Cd exposure a AtPCSl-CUS reporter gene construct appeared to be more highly expressed. Using the reporter gene construct, AtPCSl was expressed most tissues. Expression appeared to be greater in younger tissues and same higher levels of expression was observed in some regions, including carpels and the base of siliques. AtPCS2 was a functional gene encoding an active PC synthase. However, its Pattern of expression and the phenotype of a mutant (or antisense line) have not been determined. Assuming the gene is functional then it has clearly been maintained through evolution and must provide some selective advantage. This implies that, at least in some cells or tissue, it is likely to be the dominant PC synthase expressed. This remains to be determined

• Food Science and Preservation
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• v.11 no.4
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• pp.565-568
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• 2004

To investigate the effect of soy protein film packaging on the quality of beef, the rate of weight loss, pH, 2-thiobarbituric acid reactive substance (TBARS), and microbial (total bacterial count) Salmonella spp., E. coli changes were determined during storage. Beef samples were packaged with soy protein film containing rosemary extract and then stored at $4^{\circ}C$. Soy protein film was effective on prevention of weight loss, compared with the control, regardless of addition of rosemary extract. Change in pH of soy protein films containing the rosemary extract (RPF) was less during storage, compared with the control. Packaging of beef products with RPF inhibited lipid oxidation by $86\%$ at day 8 of storage, compared to the control. RPF packaging also affected the microbial growth, resulting in retardation of total bacteria by more than 1 log cycle. These results indicate that storage of beef packaged with RPF should be appropriate in terms of quality as well as shelf-life.

• Food Science and Preservation
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• v.15 no.4
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• pp.568-575
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• 2008

The antimicrobial activities of raw garlic and garlic juice heated for 30 min at $65^{\circ}C,\;80^{\circ}C,\;and\;95^{\circ}C$ were investigated. Activities against food poisoning bacteria were measured. Raw garlic and garlic juice heated at $65^{\circ}C$ showed strong antimicrobial activities, but the antimicrobial activity of garlic juice heated at $80^{\circ}C$ was much less, and no antimicrobial activity was seen in garlic juice heated at $95^{\circ}C$. Raw garlic and garlic juice heated at $65^{\circ}C$ completely inhibited the growth of Bacillus subtilis, Bacillus cereus, Staphylococcus aureus, Salmonella typhymurium, and Salmonella enteritidis at levels below 0.2%(w/v) of garlic solids. The inhibitory effects of garlic juice heated at $80^{\circ}C$ were much lower, against all bacteria tested.

• Proceedings of the Korea Crystallographic Association Conference
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• 2003.05a
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• pp.18-18
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• 2003

Thioredoxin (Trx) is a small redox protein that is ubiquitously distributed from achaes to human. In diverse organisms, the protein is involved in various physiological roles by acting as electron donor and regulators of transcription and apoptosis as well as antioxidants. Sequences of Trx within various species are 27～69% identical to that of E. coli and all Trx proteins have the same overall fold, which consists of central five β strands surrounded by four α helices. The N-terminal cysteine in WCGPC motif of Trx is redox sensitive and the motif is highly conserved. Compared with general cysteine, the N-terminal cysteine has low pKa value. The result leads to increased reduction activity of protein. Recently, novel thio.edoxin-related protein (TRP14) was found from rat brain. TRP14 acts as disulfide reductase like Trx1, and its redox potential and pKa are similar to those of Trx1. However, TRP14 takes up electrons from cytosolic thioredoxin reductase (TrxR1), not from the mitochondrial thioredoxin reductase (TrxR2). Biological roles of TES14 were reported to be involved in regulating TNF-α induced signaling pathways in different manner with Trx1. In depletion experiments, depletion of TRP14 increased TNF-α induced phosphorylation and degradation of IκBα more than the depletion Trx1 did. It also facilitated activation of JNK and p38 MAP kinase induced by TNF-α. Unlike Trx1, TRP14 shows neither interaction nor interference with ASK1. Here, we determined three-dimensional crystal structure of TRP14 by MAD method at 1.8Å. The structure reveals that the conserved cis-Pro (Pro90) and active site-W-C-X-X-C motif, which may be involved in substrate recognition similar to Trx1 , are located at the beginning position of strand β4 and helix α2, respectively. The TRP14 structure also shows that surface of TRP14 in the vicinity of the active site, which is surrounded by an extended flexible loop and an additional short a helix, is different from that of Trx1. In addition, the structure exhibits that TRP14 interact with a distinct target proteins compared with Trx1 and the binding may depend mainly on hydrophobic and charge interactions. Consequently, the structure supports biological data that the TRP14 is involved in regulating TNF-α induced signaling pathways in different manner with Trx1.

• Korean Journal of Microbiology
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• v.46 no.2
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• pp.127-133
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• 2010

The purpose of this work was to investigate the antibacterial activity derived from a lactic acid bacterium, Lactococcus lactis HK-9, isolated from the feces of a 2-day newborn infant. We characterized the physiological and biochemical properties of this strain. Both the BIOLOG system and phylogenetic analysis using 16S rRNA sequencing were utilized for identification, and the strain was assigned to the Lactococcus lactis species, designated as L. lactis HK-9, and registered in GenBank as [GU936712]. We monitored growth rate, production of lactic acid and acetic acid as metabolites, and pH during growth. The maximum concentrations of lactic acid and acetic acid reached 495.6 mM and 104.3 mM, respectively, and the initial pH of the cultures decreased from 7.0 to 4.1 after incubating for 60 h. HPLC was used to confirm the production of lactic acid and acetic acid. Significant antibacterial activity of the concentrated supernatant was demonstrated against Gram-positive (e.g., Staphylococcus aureus, Enterococcus faecalis, Listeria monocytogenes, MRSA) and Gram-negative (e.g., Escherichia coli, Salmonella enteritidis, Pseudomonas aeruginosa, Klebsiella pneumoniae, Shigella sonnei) bacteria by the plate diffusion method. The antibacterial activity was sensitive to protease, and the molecular weight of the presumed bacteriocin molecule was estimated to be about 4 kDa by tricine-SDS-PAGE.

• Korean Journal of Veterinary Service
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• v.37 no.2
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• pp.85-96
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• 2014

Total 99 strains of Campylobacter spp. were isolated from 117 cases of duck's fecal samples. Among 99 strains of Campylobacter spp. isolates, 93 strains (93.9%) were C. jejuni and 6 strains (6.1%) were C. coli. Prevalence of virulence and GBS associated genes of 72 C. jejuni isolates was determined by m-PCR. Among the 10 kinds of virulence associated genes, cadF, dnaJ, flaA and ceuE genes were detected in all of C. jejuni isolates from ducks, racR, pldA, iamA, ciaB, virB11 and docC genes were 87.5%, 84.7%, 77.8%, 48.6%, 13.9% and 11.1%, respectively. Antimicrobial susceptibility test was performed on 72 C. jejuni isolates. The rate of resistance were 62.5% for oxytetracycline, 55.6% for kanamycin, 54.2% for enrofloxacin, 50% for ciprofloxacin, 37.5% for tetracycline and nalidixic acid, 18.1% for ampicillin, 15.3% for streptomycin, and 6.9% for ofloxacin. All isolates were susceptible to erythromycin. The adherence (intracellular and extracellular bacteria) abilities of the 20 isolates to INT-407 cells were between $4.21{\pm}1.27{\times}10^4$ CFU/well and $1.053{\pm}0.451{\times}10^6$ CFU/well from the isolates of cj-55 and cj-52, respectively, and that can be expressed as 0.1033% to 5.2655% to the infecting inoculum. The invasion (intracellular bacteria) abilities of the 20 isolates to INT-407 were between $1.00{\pm}1.73{\times}10^3$ CFU/well and $8.47{\pm}5.16{\times}10^4$ CFU/well from the isolates of cj-13 and cj-47, respectively, and that can be expressed as 0.0050% to 0.4235% to the infecting inoculums. The average CFU/well of 20 campylobacters isolated from ducks for adherence to and invasion were $2.646{\pm}2.886{\times}10^5$ and $3.03{\pm}2.7{\times}10^4$ respectively, and that was $1.3230{\pm}1.2139%$ and $0.1516{\pm}0.1343%$ of the starting viable inoculum. There was considerable correlation ($R^2$=0.627) between the adherence and invasion ability of C. jejuni isolates for INT-407 cell.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.523-530
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• 1999

Sal enteritidis thin fimbriae, SEF14, were found to be restricted to the predominantly poultry-associated members of the Salmonella serogroup D1 that are considered as the important pathogens in poultry industry. SefA together with sefB and sefC encode the proteins involved in SEF14 biosynthesis. In order to develop the rapid and specific detection methods for Salmonella serogroup D1, a PCR technique for the amplification of sefA gene was established, and its specificity and sensitivity were investigated with various microorganisms. The bacterial genomic DNA was extracted by colony-picking and rapid boiled-lysate technique. In comparison of Sef I and Sef II primers used in the PCR, Sef I primer for sefA gene of 513bp showed higher specificity than that of Sef II. The established PCR was as sensitive as to detect 1pg of Sal enteritidis DNA. When 73 strains in 28 genera including the reference strains and the field isolates of various Salmonella serotypes, Bacillus subtilis, Bordetella bronchisepdca, E coli, Listeria spp., Micrococcus luteus, Rhodococcus equi, Staphylococcus spp., Streptococcus spp., Vibrio parahemolyticus, Yersinia spp. were studied, the established PCR yielded specifically positive results with only Salmonella serogroup D1. The results suggested that the PCR for sefA gene could be a potential candidate among the specific detection methods for Salmonella serogroup D1.

• Korean Journal of Veterinary Research
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• v.40 no.2
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• pp.345-360
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• 2000

The effects on CTC (T1) and CTC, Sulfathiazole and Penicillin Combination (T2) medication in feed through one life cycle of pigs, namely, weaning, mating, farrowing, lactation, growing, finishing and slaughter, were tested under local condition. In sow phase, productivity and the number of microflora in urine before and after medication of CTC were studied and average daily gain and feed conversion rate were checked during growing and finishing period. All pigs reached at 155 days old were slaughtered for pathological examination. 1. Litter size, farrowing rate and survival rate at birth were improved by CTC medication from weaning to 21th day after mating and mortality of piglet at weaning, 25 days after farrowing, was reduced in the CTC medication group, but no siginificant. 2. The number of microflora in the sow urine was changed with the medication at 200ppm of CTC in feed. In particular, the number of E coli, Samonella and Staphylococci were reduced by CTC medication. 3. The average daily gain and feed conversion rate of grower and finisher pigs was improved significantly in both treated groups, most in the high level CTC (T1) medicated group and was lowest in the control group. 4. The number of infected lungs was reduced not significant by both treatments (as % pneumonic lesions Co 66.7%, T1 47.1%, T2 31.4%) and the severity of lung lesions was significantly reduced by both high level of CTC and CTC combination medication in feed. 5. Although there were no statistical differences in atrophic rhinitis based on turbinate scores among the 3 groups, the number of mild and moderate (Grade 2 and 3) infections was higher in the control group (9/36) than in the treated groups (T1 2/34 & T2 4/35).