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ABSTRACT: Soil is the major sink for majority of pesticides applied on agricultural crops and its fate depends on variety of factors. There is little research on fate of pesticide in field soil under different climatic conditions and there is a need of study on the influence of climate on pesticide degradation and persistence in soil. In the present study, the persistence and distribution of tricyclazole was investigated in rice field soil under the influence of cold winter condition. Field experiment was carried at 35 different field sites from 6 provinces in Republic of Korea. Limit of detection and limit of quantification of tricyclazole were found to be 0.005 and 0.0165 mg/kg, respectively. The concentrations of tricyclazole in soil samples ranged from 0.387 mg/kg in sites in Gyeongsangbuk-do areas and lowest 0.021 mg/kg in sites from Chuncheongnam-do areas. In natural environmental conditions, tricyclazole persisted longer than 11 months post application in agricultural field soils. Our result indicates the influence of cold climatic condition on the persistence of tricyclazole.
Bulletin of Environmental Contamination and Toxicology 09/2012; · 1.02 Impact Factor
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ABSTRACT: A total of 223 produce samples and environmental swabs collected from various packaging sheds were examined by enumerating total aerobic plate count, total coliform, Escherichia coli and select bacterial pathogens; Bacillus cereus, E. coli, Listeria monocytogenes, Salmonella spp., and Staphylococcus aureus. B. cereus isolates were further screened for carbohydrate utilization, antibiotics susceptibility, and presence of pathogenic gene. Total aerobic plate, total coliform, and E. coli counts of fresh produce ranged from 4.6 to 6.6, 1 to 3.0, and less than 1 to 2 log CFU/g, respectively. The prevalence of pathogens for all samples was 21.5%, and 0.89% for B. cereus and S. aureus, respectively. However, no pathogenic E. coli, L. monocytogenes, and Salmonella spp. were detected. Most of the B. cereus isolates identified were susceptible to penicillin, polymyxin B, ampicillin, oxacillin, and cefotaxime, whereas none of the isolates were positive for emetic toxin, an indication that cleansing procedure at the packaging sheds was not effective. Thorough sanitation and aseptic handling of fresh produce through out the packaging facilities is accentuated. Fresh fruits and vegetables, essential component of the regular human diet with health and nutritional benefits, are in great demand in Korea, and its consumption and production has been increasing during the past decades [http://faostat.fao.org/site/339/default.aspx]. Accordingly, the number of foodborne illness outbreaks caused by consumption of bacterial contaminated fruits and vegetables has increased. In the past, food poisoning incidences mainly occurred between the months of May and September. However, recently food poisoning has occurred year-round due to environmental changes such as global warming and the elevation of room temperature. Agricultural products have been linked to various pathogens that plague humans. The most common outbreaks have been caused by pathogens namely, pathogenic Escherichia coli, Listeria monocytogenes, Salmonella spp., Bacillus cereus, and Staphylococcus aureus [Heisick et al., 1989; Beuchat, 1996; Fang et al., 1999], the last three being the major food poisoning bacteria in Korea for a long time [Park et al., 2001]. Pathogens contaminate agricultural products at all stages from farm to table during production, harvest, processing, and transporting, as well as in packaging, retail, and food service establishments [Ruiz et al.,]. Soil, fecal matter of both domestic and wild animals, contaminated water used for irrigation, floodwater, and water used for washing have been identified as sources of contamination [Beuchat, 1996]. The processing steps typically involve human contact, immersion in water, and cutting or slicing steps. These steps have the potential for contaminating fresh produce, as well increasing the growth of these contaminants [Brackett, 1994]. Fresh produce could pose food safety risk, because they are consumed raw and thus are susceptible to contamination by different sources.
Journal of the Korean Society for Applied Biological Chemistry 01/2011; 54:243--253. · 0.37 Impact Factor
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ABSTRACT: Kalopanax pictus is a deciduous tree used in traditional medicine; its leaves are also consumed as a vegetable. In this study, the ethyl acetate fraction of K. pictus leaves (EFK) was tested in vitro for anticancer activity against four cell lines: human colon cancer (HT-29) cells, human stomach cancer (NCI-N87) cells, human breast cancer (MDA-MB231) cells, and mouse melanoma (B16F1) cells. Results indicated that EFK showed the most potent tumor selective growth inhibitory activity against HT-29 cells with less cytotoxic effect on normal cell lines. Cytotoxicity of EFK on HT-29 cells was associated mainly with cell chromatin condensation, DNA fragmentation, and loss of membrane phospholipid asymmetry with appearance of G2/M phase arrest. Cell death induced by EFK displayed features characteristic of apoptosis, and was associated with generation of reactive oxygen species (ROS) and increase of Bax/Bcl-2 ratio. These findings suggest that K. pictus leaves have anticancer properties and may be valuable for application in pharmaceutical industry.
Bioresource technology 12/2010; 101(23):9366-72. · 4.25 Impact Factor
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ABSTRACT: The Japanese Erwinia strain Ejp617 is a plant pathogen that causes bacterial shoot blight of pear in Japan. Here, we report the complete genome sequence of strain Ejp617 isolated from Nashi pears in Japan to provide further valuable insight among related Erwinia species.
Journal of bacteriology 11/2010; 193(2):586-7. · 3.94 Impact Factor
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ABSTRACT: A rapid high-throughput, specific and sensitive (polymerase chain reaction) PCR-based assay coupled with DNA hybridization technique for the detection of deep bark canker (DBC) pathogen Brenneria rubrifaciens directly from mixed bacterial cells and in planta was developed. These result shows that the specific genetic markers have a powerful potential to detect B. rubrifaciens directly from crude samples at field conditions.
African journal of microbiology research 09/2010; 4:1754--1757. · 0.54 Impact Factor
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ABSTRACT: We designed a sensitive and specific PCR-based method
with enterobacterial repetitive intergenic consensus
(ERIC) primer to detect Erwinia pyrifoliae, which cause
shoot blight in Asian pear, from a mixed culture and
infected plant materials. The primers specifically detected
only E. pyrifoliae and showed no cross-reactivity with
other bacterial phytopathogens.
The plant pathology journal 08/2010; 26(3):267-270. · 0.53 Impact Factor
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Byung Ryong Lee,
Yeom Pyo Lee,
Dae Won Kim,
Ha Yong Song,
Ki-Yeon Yoo,
Moo Ho Won,
Tae-Cheon Kang,
Kwang Jae Lee,
Kyung Hee Kim,
Jin Ho Joo,
Hun Ju Ham, Jang Hyun Hur,
Sung-Woo Cho,
Kyu Hyung Han,
Kil Soo Lee,
Jinseu Park,
Won Sik Eum,
Soo Young Choi
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ABSTRACT: The aim of this study was to investigate the preventive effect of Agrocybe chaxingu polysaccharide on streptozocin (STZ)-induced pancreatic beta-cells destruction. Agrocybe chaxingu polysaccharide markedly reduced nitric oxide (NO) production and iNOS expression levels in RINm5F cells in a dose-dependent manner. In addition, Agrocybe chaxingu polysaccharide significantly inhibited iNOS expression and blood glucose levels in STZ-induced diabetic mice. Moreover, immunohistochemical analysis revealed that it enhanced pancreatic beta-cells resistance to destruction by STZ. These results suggest that Agrocybe chaxingu polysaccharide may have value as a therapeutic agent against diabetes mellitus.
Molecules and Cells 03/2010; 29(4):349-54. · 2.18 Impact Factor
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Byung Ryong Lee,
So Young Kim,
Dae Won Kim,
Jae Jin An,
Ha Yong Song,
Ki Yeon Yoo,
Tae Cheon Kang,
Moo Ho Won,
Kwang Jae Lee,
Kwang Hee Kim,
Jin Ho Joo,
Hun Ju Ham, Jang Hyun Hur,
Sung Woo Cho,
Kyu Hyung Han,
Kil Soo Lee,
Jinseu Park,
Soo Young Choi,
Won Sik Eum
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ABSTRACT: The inhibition of nitric oxide (NO) and cyclooxygenase-2 (COX-2) production is considered to be a promising approach to the treatment of various diseases, including inflammation and cancer. In this study, we examined the effects of the Agrocybe chaxingu beta-glucan (polysaccharide) on lipopolysaccaride (LPS)-induced nitric oxide (NO) and cyclooxygenase-2 (COX-2) expression in murine macrophage Raw 264.7 cells as well as 12-O-tetradecanoylphorbol 13-acetate (TPA)-induced ear edema in mice. The polysaccharide significantly inhibited (P 0.01) LPS-induced iNOS and COX-2 expression levels in the cells. Furthermore, topical application of polysaccharide resulted in markedly inhibited (P 0.01) TPA-induced ear edema in mice. These results suggest that this polysaccharide may be used for NO- and COX-2-related disorders such as inflammation and cancer.
BMB reports 12/2009; 42(12):794-9. · 1.72 Impact Factor
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ABSTRACT: The potential antiviral effects of the culture filtrates
(CF) from Serratia marcescens strain Gsm01 against
yellow strain of Cucumber mosaic virus (CMV-Y) were
investigated. The culture filtrate of S. marcescens strain
Gsm01 applied on Chenopodium amaranticolor showed
high inhibitory activity, likewise no necrosis appeared
when applied on the tobacco plants 2 days before CMVY
inoculation. When plants were challenge inoculated
with CMV-Y for eighteen days, the disease incidence in
plants with culture filtrate of S. marcescens Gsm01 did
not exceed 59%, whereas 100% of control plants were
severely infected. The results of double antibody sandwich-
enzyme linked immunosorbent assay (DAS-ELISA),
reverse transcriptase polymerase chain reaction (RTPCR),
dot blotting, and western blotting showed that
culture filtrate treatment highly affected the accumulation
of CMV-Y or its CP protein gene in the treated plant
leaves. It was also observed that the culture filtrate had
no RNase activity on genomic RNAs of CMV-Y, suggesting
that culture filtrate may not contain ribosome
inactivating proteins (RIPs) or proteins with RNase
activity. These data shows that culture filtrate of S.
marcescens strain Gsm01 seems to be a promising
source of antiviral substance for the practical use.
The plant pathology journal 10/2009; 25(4):369-375. · 0.53 Impact Factor
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ABSTRACT: Three beneficial bacterial agents, Lactobacillus strain KLF01, Lactococcus strain KLC02 and Paenibacillus strain KPB3 were showed clear zone against plated Pectobacterium carotovorum subsp. carotovorum (Pcc) soft rot pathogen. In greenhouse test, bio-control efficacy was more significantly effective in the treatments by KLC02 and KPB3 as 64%, 50%, 56% and 66%, 57%, 58% according to date of evaluation, respectively. In case of KLF01 control effect was relatively lower than treatments of KLC02 and KPB3 but its efficacy was still significantly observed when compared to control (only water treatment). Furthermore, KLF01, KLC02 and KPB3 showed 55%, 60% and 62% bio-control efficacy, respectively in field test from early March to late July of 2009. Thus, we suggest that these strains can be useful as bio-control agents against soft rot caused by Pcc. Abstract *연락저자 : Tel.
The Korean Journal of Pesticide Science. 09/2009;
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ABSTRACT: Abstract A new putative transposon was identified in the tobacco budworm, Heliothis virescens. This transposon was characterized as a full length CORE-SINE (65 bp of “CORE” core specific nucleotide short interspersed elements) that resembled sequences from three other lepidopterans and humans. In particular, the A-box and B-box regions of this sequence most closely conformed to the signature of CORE-SINEs from widely divergent species. This CORE-SINE was present as a polymorphism in a hypervariable region of the gene hscp, which is the target of pyrethroid insecticides and other xenobiotics in the nerve axon. We described this new putative transposon as Noct-1 due to its presence in a noctuid moth. This is the first description of a full-length CORE-SINE with the A-box, B-box, target site duplication, and candidate core domain from an insect.
Insect Science 05/2009; 16(3):219 - 226. · 1.10 Impact Factor
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Plant pathology journal. 01/2009; 2(5):7-7.
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ABSTRACT: The disease-specific (dsp) region and the hypersensitive response and pathogenicity (hrp) genes, including the hrpW, hrpNEp, and hrpC operons have previously been sequenced in Erwinia pyrifoliae WT3 [Shrestha et al. (2005a)]. In this study, the remaining hrp genes, including the hrpC, hrpA, hrpS, hrpXY, hrpL and hrpJ operons, were determined. The hrp genes cluster (ca. 38 kb) was comprised of eight transcriptional units and contained nine hrc (hrp conserved) genes. The genetic organization of the hrp/hrc genes and their orientation for the transcriptions were also similar to and collinear with those of E. amylovora, showing > or = 80% homologies. However, ORFU1 and ORFU2 of unknown functions, present between the hrpA and hrpS operons of E. amylovora, were absent in E. pyrifoliae. To determine the HR active domains, several proteins were prepared from truncated fragments of the N-terminal and the C-terminal regions of HrpN(Ep) protein of E. pyrifoliae. The proteins prepared from the N-terminal region elicited HR, but not from those of the C-terminal region indicating that HR active domains are located in only N-terminal region of the HrpN(Ep) protein. Two synthetic oligopeptides produced HR on tobacco confirming presence of two HR active domains in the HrpN(Ep). The HR positive N-terminal fragment (HN delta C187) was further narrowed down by deleting C-terminal amino acids and internal amino acids to investigate whether amino acid insertion region have role in faster and stronger HR activity in HrpN(Ep) than HrpN(Ea). The HrpN(Ep) mutant proteins HN delta C187 (D1AIR), HN delta C187 (D2AIR) and HN delta C187 (DM41) retained similar HR activation to that of wild-type HrpN(Ep). However, the HrpN(Ep) mutant protein HN delta C187 (D3AIR) lacking third amino acid insertion region (102 to 113 aa) reduced HR when compared to that of wild-type HrpN(Ep). Reduction in HR elicitation could not be observed when single amino acids at different positions were substituted at third amino acids insertion region. But, substitution of amino acids at L103R, L106K and L110R showed reduction in HR activity on tobacco suggesting their importance in activation of HR faster in the HrpN(Ep) although it requires further detailed analysis.
Molecules and Cells 02/2008; 25(1):30-42. · 2.18 Impact Factor
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ABSTRACT: The potential of the exopolysaccharide (EPS) from a Serratia sp. strain Gsm01 as an antiviral agent against a yellow strain of Cucumber mosaic virus (CMV-Y) was evaluated in tobacco plants (Nicotiana tabacum cv. Xanthi-nc). The spray treatment of plants using an EPS preparation, 72 before CMV-Y inoculation, protected them against symptom appearance. Fifteen days after challenge inoculation with CMVY, 33.33% of plants showed mosaic symptoms in EPS-treated plants compared with 100% in the control plants. The EPS-treated plants, which showed mosaic symptoms, appeared three days later than the controls. The enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR) analyses of the leaves of the protected plants revealed that the EPS treatment affected virus accumulation in those plants. Analysis of phenylalanine ammonia lyase, peroxidase, and phenols in protected plants revealed enhanced accumulation of these substances. The pathogenesis-related (PR) genes expression represented by PR-1b was increased in EPS-treated plants. This is the first report of a systemic induction of protection triggered by EPS produced by Serratia sp. against CMV-Y.
Journal of Microbiology and Biotechnology 02/2008; 18(1):67-73. · 1.38 Impact Factor
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ABSTRACT: AtNDPK2 is involved in transcriptional regulation in response to pathogen and abiotic stresses. AtNDPK2-expressing transgenic rice plants showed regulation of the marker genes for chilling and oxidative stresses. In the present study, we produced AtNDPK2-overexpressing transgenic rice lines using the co-transformation method. Morphologically, the transgenic plants, compared with the control plants, were growth retarded. We investigated how AtNDPK2 overexpression influences the response of rice plants to marker genes related to chilling and ROS stress. The accumulation of transcripts of pBC442 and pBC601, related to chilling stress, was induced in AtNDPK2-overexpressed rice plants. On further investigation, we found that OsAPX1-, OsAPX2-, and OsSodB-scavenging free-oxygen radicals, such as superoxide (O2-) and hydrogen peroxide (H(2)O(2)), could be induced in AtNDPK2-overexpressed rice plants. In particular, transcripts encoding pathogenesis-related (PR) proteins OsPR2 and OsPR4, as well as oxidative stress response proteins, were confirmed to change the gene expression in the transgenic rice plants. Together, these results suggest that AtNDPK2 plays a regulatory role in chilling and antioxidant signaling in plants.
Biochemical and Biophysical Research Communications 12/2007; 363(1):126-32. · 2.48 Impact Factor
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ABSTRACT: CaKR1 from pepper leaves encodes an ankyrin repeat domain zinc finger that is thought to be involved in transcriptional regulation in response to pathogens and abiotic stresses. Transgenic tomato plants expressing CaKR1 show enhanced resistance to Phytophthora infestans. In this study, we further characterized this CaKR1-overexpressing transgenic tomato line. Morphologically, the leaves of the transgenic plants were thicker than those of control plants. Overexpressed transgenic plants also produced lower levels of free oxygen radicals, such as superoxide (O2-) and hydrogen peroxide (H2O2), and showed enhanced resistance to salinity and oxidative stress. In particular, transgenic plants produced higher levels of transcripts encoding the pathogenesis-related (PR) proteins LePR1, LePR2, and LePR3, as well as oxidative stress response proteins, such as superoxide dismutase (LeSOD2) and ascorbate peroxidase (LeAPX2 and LeAPX3). These results suggest that CaKR1 is a key signaling molecule regulating plant antioxidant metabolism and defense responses.
Biochemical and Biophysical Research Communications 12/2007; 363(4):983-8. · 2.48 Impact Factor
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ABSTRACT: This article has been withdrawn at the request of the author. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
Biochemical and Biophysical Research Communications 12/2007; · 2.48 Impact Factor
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ABSTRACT: HrpN(EP), from the gram-negative pathogen, Erwinia pyrifoliae, is a member of the harpin group of proteins, inducing pathogen resistance and hypersensitive cell death in plants. When the hrpN(EP) gene driven by the OsCc1 promoter was introduced into tobacco plants via Agrobacterium-mediated transformation, their resistance to the necrotrophic fungal pathogen, Botrytis cinerea, increased. Resistance to B. cinerea was correlated with enhanced induction of SA-dependent genes such as PR-1a, PR2, PR3 and Chia5, of JA-dependent genes such as PR-1b, and of genes related to ethylene production, such as NT-EFE26, NT-1A1C, DS321, NT-ACS1 and NT-ACS2. However the expression of NPR1, which is thought to be essential for multiple-resistance, did not increase. Since the pattern of expression of defense-related genes in hrpN(EP)-expressing tobacco differed from that in plants expressing hpaG(Xoo) from Xanthomonas oryzae pv. Oryzae, these results suggest that different harpins can affect the expression of different defense-related genes, as well as resistance to different plant pathogens.
Molecules and Cells 11/2007; 24(2):232-9. · 2.18 Impact Factor
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Nagesh S Ipper,
Seon Hwa Lee,
Ki Jung,
Anupama Suk,
Shrestha,
Uk Dong,
Duck Hwan Seo,
Jun Mo Park,
Cho,
Dong Sik Park, Jang Hyun Hur,
Chun Keun Lim
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ABSTRACT: An Antiviral producing bacterial strain was isolated from ginseng root environment in Hongcheon, Kangwon province of Republic of Korea. Identification of this bacterial strain was performed by physiological and biochemical tests along with 16S rRNA analyses. The results revealed that the bacterium was closer to genus Serratia, which was named as Gsm01. The strain was grown in Mannitol-Glutamate-Yeast (MGY) broth for 48 h. The culture was centrifuged and the filtrate obtained was tested for its ability to control Cucumber mosaic virus strain Y (CMV-Y) in greenhouse and field experiments. In the green house experiments, CF was evaluated for its ability to protect local host, Chenopodium amaranticolor and systemic host of CMV, Nicotiana tabacum cv. Xanthi-nc. It was found that, CF treatment reduced viral infection by 98% in local host; C. amaranticolor. The N. tabacum cv. Xanthi-nc plants treated with CF did not show visible viral symptoms 15 days post inoculation (dpi) and remained symptomless throughout the periods of the study. To evaluate effectiveness of CF under field conditions, experiment was carried out in a polyvinyl house. It was observed that, 52% plants were protected from viral diseases compared to non-treated plants, increasing the crop yield. This is the first report showing antiviral activity of a Serratia spp. against CMV.
The Korean Journal of Pesticide Science. 01/2006; 10:344-350.
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ABSTRACT: Two hundred bacterial strains were isolated from the soil around healthy tomato plants in a polyvinyl house, where most of the other plants showed bacterial wilt symptoms. The strains were screened in vitro for their antibacterial activity. Among them, a strain, KPB3 showed strong bactericidal activity against bacterial wilt pathogen, Ralstonia solanacearum. The strain KPB3 was identified using physiological and biochemical tests, and 16S rRNA analyses. Based on these tests, the strain was found to be closer to genus Paenibacillus. To control the bacterial wilt caused by R. solanacearum, greenhouse experiments were conducted to determine the effectiveness of the Paenibacillus strain KPB3. Drench application of this strain (4×10 8 CFU mL -1) into the pots containing tomato plants, post-inoculated with the pathogen, R. solanacearum could drastically reduce the disease severity, compared to the non-treated plants. To evaluate effectiveness of this strain under field conditions, experiments were carried out in polyvinyl houses infested with R. solanacearum, during spring and autumn of the year 2006. It was observed that, during spring, bacterial wilt was more prevalent compared to the autumn. During spring, 50.9% disease incidences occurred in non-treated controls, while, Paenibacillus strain KPB3 treated plants showed 24.6% disease incidences. Similarly, during autumn, around 17.2% plants were infected with bacterial wilt in non-treated polyvinyl houses, compared to the Paenibacillus strain KPB3 treated plants, which showed 7.0% disease incidences. These results demonstrated that, Paenibacillus strain KPB3 is a potential biological control agent against bacterial wilt caused by R. solanacearum, effective under greenhouse as well as field conditions. This is the first report showing biocontrol of R. solanacearum using a Paenibacillus spp. under field conditions.
The Korean Journal of Pesticide Science. 01/2006; 10:313-319.
