• Journal of Microbiology and Biotechnology
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• v.18 no.10
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• pp.1689-1694
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• 2008

The ability to detect Salmonella spp. is essential in the prevention of foodborne illness. This study examined a Salmonella spp. detection method involving the application of immunomagnetic separation and immunoliposomes (IMS/IL) encapsulating sulforhodamine B (SRB), a fluorescent dye. A quantitative assay was conducted by measuring the fluorescence intensity of SRB that was produced from an immunomagnetic bead-Salmonella spp.-immunoliposome complex. The results indicated detection limits of $2.7{\times}10^{5}$ and $5.2{\times}10^{3}$ CFU/ml for Salmonella enterica subsp. enterica serovar Enteritidis (S. Enteritidis) and Salmonella enterka subsp. enterka serovar Typhimurium (S. Typhimurium), respectivley. The signal/noise ratio was improved by using 4% skim milk as a wash solution rather than 2% BSA. In addition, higher fluorescence intensity was obtained by increasing the liposome size. Compared with the conventional plating method, which takes 3-4 days for the isolation and identification of Salmonella spp., the total assay time of to h only including 6 h of culture enrichment was necessary for the Salmonella detection by IMS/IL. These results indicate that the IMS/ IL has great potential as an alternative rapid method for Salmonella detection.

• Mycobiology
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• v.31 no.2
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• pp.74-80
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• 2003

Isolates of Trichoderma spp. collected from Pleurotus ostreatus and P. eryngii beds, which included loosened substrate compactness and development of green colour, were grouped into three species. The occurrence of different species of Trichoderma was as T. cf. virens(70.8%), T. longibrachiatum(16.7%) and T. harzianum(12.5%). The conidia of Trichoderma spp. were ellipsoidal, obovoid and phialides were bowling pins, lageniform and the length of phialides was $3.5{\sim}10.0{\times}1.3{\sim}3.3{\mu}m$. Phialides of T. cf. virens and T. harzianum were tending clustered, but it was solitary disposition in T. longibrachiatum. T. cf. virens was characterized by predominantly effuse conidiation, sparingly branched, and fertile to the apex and it was penicillate type. RAPD analysis could detect variability amongst three different species of Trichoderma using two newly designed URP-primers. However, intra-specific variation could not be detected in all the isolates except for rDNA sequence data classified Trichoderma isolates into three distinct groups representing three species. The profiles of rDNA sequences of isolates representing a species showed high similarity in T. cf. virens and T. harzianum. However, there was a variation in rDNA sequences of isolates representing T. longibrachiatum. The results of present study reveals that molecular techniques of RAPD and rDNA sequencing can greatly aid in classification based on morphology and precise identification of fast evolving species of Trichoderma.

• Journal of Ecology and Environment
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• v.37 no.4
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• pp.225-229
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• 2014

Feeding behavior of Temora turbinata was investigated through laboratory experiments with special emphasis on its food preference and consequent clearance rate on diatom and microbial components given as common natural food assemblage of coastal area (Uchiumi, Uwa Sea, Japan). Among available prey items, T. turbinata showed the highest clearance rate for Thalassiosira spp. ($0.23{\pm}0.08L\;Temora^{-1}day^{-1}$) followed by Chaetoceros spp. ($0.11{\pm}0.03L\;Temora^{-1}day^{-1}$), but clearance rates for other diatom, Nitzschia spp. was lower (0.03 to $0.07L\;Temora^{-1}day^{-1}$). Bacterial abundances showed no response against 24-h feeding of T. turbinata. Feeding of T. turbinata on heterotrophic nanoflagellates (HNF) was apparent when clearance rates of T. turbinata on diatoms were relatively low, but T. turbinata did not consume HNF as well as ciliates with Thalassiosira spp. of which clearance rate was highest. The results suggest that HNF and ciliates are possible supplementary prey item for T. turbinata, but their contribution as food sources can be limited by the presence of other prey items such as preferable diatom species.

• Mycobiology
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• v.33 no.1
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• pp.35-40
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• 2005

Selected isolates of Pseudomonas fluorescens (Pf4-92 and PfRsC5) and P. aeruginosa (PaRsG18 and PaRsG27) were examined for growth promotion and induced systemic resistance against Fusarium wilt of chickpea. Significant increase in plant height was observed in Pseudomonas treated plants. However, plant growth was inhibited when isolates of Pseudomonas were used in combination with Fusarium oxysporum f. sp. ciceri (FocRs1). It was also observed that the Pseudomonas spp. was colonized in root of chickpea and significantly suppressed the disease in greenhouse condition. Rock wool bioassay technique was used to study the effect of iron availability on the induction of systemic resistance to Fusarium wilt of chickpea mediated by the Pseudomonas spp. All the isolates of Pseudomonas spp. showed greater disease control in the induced systemic resistance (ISR) bioassay when iron availability in the nutrient solution was low. High performance liquid chromatography (HPLC) analysis indicated that an the bacterial isolates produced more salicylic acid (SA) at low iron ($10\;{\mu}M$ EDDHA) than high iron availability ($10\;{\mu}Fe^{3+}$ EDDHA). Except PaRsG27, all the three isolates produced more pseudobactin at low iron than high iron availability.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.71.1-71
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• 2003

Most major plant pathogenic bacteria in Korea belong to Xanthomonas spp.. Xanthomonas oryzae pv. oryzae is a major pathogen in rice, X. campestris pv. vesicatoria in pepper, X. axonopodis pv. giycines in soybean, X. campestris pv. campestris in cabbage, and X. axonoposid pv. citri in tangerin. Host specificity of the bacterial pathogen depends on the avirulence gene in the pathogen and the corresponding resistance gene in host plants. Many avirulence genes in bacteiral pathogen located on the native plasmids. However, the presence of the native plasmids in Xanthomonas spp. was not investigated well. In order to study the host specificity, we isolated native plasmids from Xanthomonas spp. and compared those plasmids each other, The presence of the native plasmids and the characteristics of the plasmids depended on the bacterial strains. In the X. axonopodis pv. glycines, most strains carried native plasmids but some strains did not. Some strains carry about 60 kb native plasmids including 3 different aviurlence genes. We will discuss the characteristics of the native plasmids isolated from the Xanthomonas spp.

• Journal of Food Hygiene and Safety
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• v.21 no.3
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• pp.159-163
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• 2006

37 Bacillus spp strains(43.0%=37/86), and 18 B. cereus(20.9%=18/86) were isolated on 86 dried marine products. Each isolates were B. cereus 48.6%(18/37), B. mycoides 13.5%(5/37) B. coagulus 5.4%(2/37) B. firmus 5.4%(2/37), B. circulus 2.7%(1/37), B. stearothermophilus 2.7%(1/37), B. pumilus 2.7%(1/37) B. spp. 8.1%(3/37), and Brebacillus brevis 10.8%(4/37) etc.

• The Journal of the Korean Society for Microbiology
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• v.11 no.1
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• pp.79-85
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• 1976

There are many of anaerobic culture methods and equipments for isolation and cultivation of anaerabic bacteria, but most of these methods are used without pre-reduced media. Gas-jet method is a recommend. able method for the culture of anaerobes, resently developed. Bacteriological studies were experimented of liver abscess of cattle by the use of gas. jet method. The results were summarised as follows; 1. Gas-jet method for anaerobic culture are expedient for the making of pre-reduced media, maintaining of oxygen free condition in the culture tube, picking of bacteria from colony and colony counting etc. 2. A 121 strains of facultative anaerobic and anaerobic bacteria were isolated from liver abscess of 27 head of cattle, and the isolated anaerobic bacteria were as follows. Peptostreptococcus spp. 7 strains Acid aminococcus fermentans 1 Veillonella spp. 1 Bacterioides spp. 6 Bifidobacterium spp. 4 Arachinia propionica 2 Lactobacillus spp. 4 Propionibacterium acnes 1 3. Liver abscess were infected with many of bacteria, about $10^3-10^9$ numbers per gram of abcessed tissue. Almost of abscess were mixed infection of various bacterial species rather than simple species.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.350-357
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• 1998

A total of 12 strains of fluorescent Pseudomonas isolated from the cultivated mushrooms such as Agaricus bisporus and Pleurotus ostreatus were collected. They consisted of pathogenic Pseudomonas spp. and epiphytic Pseudomonas spp. of the cultivated mushroom. To analyze the phylogenetic relationship of these strains, ITS I region, the 16S-23S intergenic spacer region in the ribosomal RNA (rRNA) operon, was cloned and sequenced. The spacer regions of these strains were 495∼527 nucleotides in length and contained the genes encoding isoleucine-tRNA (tRNAIle) and alanine-tRNA (tRNAAla). The reciprocal homologies of each ITS I sequence among these strains were in the range of 84.2%∼98.8%. According to the analysis of ITS I sequences, the fluorescent Pseudomonas spp. were phylogenetically classified into three clusters. Cluster I consisted of Pseudomonas fluorescens, P. tolaasii, P. gingeri’, and P.‘reactans’(WLRO). Cluster II comprised Pseudomonas fluorescens biovar C and F. Cluster III composed P. agarici. Cluster I and II could be classified into P. fluorescens complex. P. agarici formed an independent taxon clearly separable from P. florescens complex.

• Journal of Microbiology and Biotechnology
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• v.26 no.9
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• pp.1551-1556
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• 2016

Broiler meat production worldwide has been plagued by lethal food-poisoning bacteria diseases, including listeriosis. A fatality rate of 15.6% was recorded in human beings in the EU in 2015. During 2013, a total of 200 poultry farm samples, including litter, chicken breast, farm feed, and drinking water, were collected to generate baseline data for the characterization of the genus Listeria in broiler poultry farms. Listeria spp. were detected in a total of 95 (47.5%) poultry farm samples. The isolates of Listeria spp. included L. innocua (28.5%), L. ivanovii (12.5%), L. welshimeri (4.5%), and L. monocytogenes and L. seeligeri (1% each). Listeria spp. contamination rates were higher in farm feed (70%), followed by litter (52.5%), chicken breasts (42.2%), and drinking water (10%). Almost all Listeria spp. isolates were resistant to more than three classes of antibiotics (multidrug resistant). Besides this, we observed a significant resistance level to penicillin and fluoroquinolone drugs. However, lower resistance levels were recorded for broad-spectrum cephalosporins. The inlA, inlC, and inlJ virulence genes were detected in almost all of the L. monocytogenes isolates. Thus, food safety management approaches and interventions at all stages of the broiler rearing cycle were needed to control cross-contamination and the zoonotic potential of listeriosis.

• Microbiology and Biotechnology Letters
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• v.11 no.1
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• pp.1-4
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• 1983

In order to determine a proper amount of sodium pyrophosphate (SPP) which protect Lactobacilli from phage attack, Lactobacillus casei YIT-9018 was grown in $Ca^{＋＋}$ free Murata medium having various concentrations of SPP after infections with phage Jl at different multiplicities of infection (MOI). it was found that the level of SPP to inhibit phage activity depended upon the level of MOIs. When the bacteria were infected by less than 10$^{-1}$ of MOI, 0.15% of SPP was sufficient, while with 10$^{0}$ of MOI, 0.175% of SPP was needed to inhibit the lytic activity completely.