• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2000년도 춘계수산관련학회 공동학술대회발표요지집
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• pp.71-73
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• 2000

Campylobacter jejuni is most frequently identified cause of cause of acute diarrhoeal infections in developeed countries, exceeding rates of illness caused by both salmonella and shigilla(Skirrow, 1990 ; Lior 1994). Previous studies on campylobacter jejuni contamination of commercial broiler carcasses in u.s.(Stern, 1992). Most cases of the disease result from indirect transmission of Campylobactor from animals via milk, water and meat. In addition to Campylobactor jejuni. the closely relates species Campylobactor coli and Campylobactor lari have also been implicated as agents of gastroenteritis in humans. Campylobactor coli represented only approximately 3% of the Campylobactor isolates from patients with Campylobactor enteritis(Griffiths and Park, 1990) whereas Campylobactor coli is mainly isolated from pork(Lmmerding et al., 1988). Campylobactor jejuni has also been isolated from cases of bacteremia, appendicitis and, recently, has been associated with Guillai-Barre syndrome(Allos and Blaser, 1994; von Wulffen et al., 1994; Phillips, 1995). Studies in volunteers indicated that the infectious dose for Campylobactor jejuni is low(about 500 organisms)(Robinson, 1981). The methods traditionally used to detect Campylobactor ssp. in food require at least two days of incubation in an enrichment broth followed by plating and two days of incubation on complex culture media containing many antibiotics(Goossens and Butzler, 1992). Finnaly, several biochemical tests must be done to confirm the indentification at the species level. Therfore, sensitive and specific methods for the detection of small numbers of Campylobactor cells in food are needed. Polymerase chain reaction(PCR) assays targeting specific DNA sequences have been developed for the detection of Campylobactor(Giesendorf and Quint, 1995; Hemandex et al., 1995; Winter and Slavidk, 1995). In most cases, a short enrichment step is needed to enhance the sensitivity of the assay prior to detection by PCR as the number of bacteria in the food products is low in comparison with those found in dinical samples, and because the complex composition of food matrices can hinder the PCR and lower its sensitivity. However, these PCR systems are technically demanding to carry out and cumbersome when processing a large number of samples simutaneously. In this paper, an immunomagnetic method to concentrate Campylobactor cells present in food or clinical samples after an enrichment step is described. To detect specifically the thermophilic Campylobactor. a monoclonal antibody was adsorbed on the surface of the magnetic beads which react against a major porin of 45kDa present on the surface of the cells(Huyer et al., 1986). After this partial purification and concentration step, detection of bound cells was achieved using a simple, inexpensive microtitre plate-based hybridization system. We examined two alternative detection systems, one specific for thermophilic Campylobactor based on the detection of 23S rRNA using an immobilized DNA probe. The second system is less specific but more sensitive because of the high copy number of the rRNA present in bacterial cell($10^3-10^4$). By using specific immunomagnetic beads against thermophilic Campylobactor, it was possible to concentrate these cells from a heterogeneous media and obtain highly specific hybridization reactions with good sensitivity. There are several advantages in using microtitre plates instead of filter membranes or other matrices for hybridization techniques. Microtitre plates are much easier to handle than filter membranes during the adsorption, washing, hybridization and detection steps, and their use faciilitates the simultanuous analysis of multiple sample. Here we report on the use of a very simple detection procedure based on a monoclonal anti-RNA-DNA hybrid antibody(Fliss et al., 1999) for detection of the RNA-DNA hybrids formed in the wells.

• 한국어류학회지
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• 제17권1호
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• pp.8-18
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• 2005

진동만 명주리 잘피밭에 서식하는 어류의 종조성 및 계절변동을 조사하기 위해서 2001년 8월 부터 2003년 7월까지 소형 비임트롤을 이용하여 어류를 매월 채집하였다. 조사기간 동안 어류는 총 33종이 채집되었다. 쥐노래미, 흰베도라치, 실양태, 가시망둑, 베도라치, 그물코쥐치, 실고기, 그리고 조피볼락이 많이 채집되었는데, 이들은 채집된 총 개체수의 79.5%를 차지하였다. 본 조사해역에서 채집된 어류는 대부분이 평균 15 cm 이하의 소형 어종이거나 대형 어종의 유어들로 구성되어 있었다. 잘피밭 어류군집은 뚜렷한 계절변동을 보였는데, 채집 개체수는 2002년 4월에서 6월 사이에 아주 높았으나, 생체량은 2001년과 2002년 9월에 각각 가장 높은 수치를 나타내었다. 대체적으로 겨울철에서는 채집 개체수 및 생체량이 모두 낮았다. 어류 군집의 계절변동은 잘피의현존량 및 먹이생물의 양적변동과 관계가 있었다.

• Journal of Microbiology and Biotechnology
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• 제26권1호
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• pp.130-138
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• 2016

The use of antibiotics in aquaculture raises environmental and food safety concerns because chronic exposure of an aquatic ecosystem to antibiotics can result in the spread of antibiotic resistance, bioaccumulation of antibiotics in the organisms, and transfer of antibiotics to humans. In an attempt to overcome these problems, high-concentration red clay was applied as an alternative antibiotic against the following common fish pathogens: Aeromonas salmonicida, Vibrio alginolyticus, and Streptococcus equinus. The growth of A. salmonicida and V. alginolyticus was retarded by red clay, whereas that of S. equinus was promoted. Phase contrast and scanning electron microscopy analyses confirmed the attachment of red clay on cell surfaces, resulting in rapid gravitational removal and cell surface damage in both A. salmonicida and V. alginolyticus, but not in S. equinus. Different cell wall properties of grampositive species may explain the unharmed cell surface of S. equinus. Significant levels of oxidative stress were generated in only the former two species, whereas significant changes in membrane permeability were found only in S. equinus, probably because of its physiological adaptation. The bacterial communities in water samples from Oncorhynchus mykiss aquacultures supplemented with red clay showed similar structure and diversity as those from oxytetracycline-treated water. Taken together, the antibiotic effects of high concentrations of red clay in aquaculture can be attributed to gravitational removal, cell surface damage, and oxidative stress production, and suggest that red clay may be used as an alternative for antibiotics in aquaculture.

• 한국균학회소식:학술대회논문집
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• 한국균학회 2015년도 춘계학술대회 및 임시총회
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• pp.19-19
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• 2015

The term of Mushrooms means to spread like the April showers. After 18th century, the mycelium and spores of mushrooms were observed by microscope and then was denominated as fungi. About one hundred thousand species of mushrooms in appearance were worldly reported, and in Korea about four thousand species of mushrooms are estimated. In Korea, total of one thousand nine hundred one species of mushrooms have been recorded. Mushrooms belonging to the group of organisms called fungi, which must obtain their food from living plants or animals or from their remains after death. A large number of mushrooms grow in association with the roots of trees and other woody plants, called mycorrhizal fungi, both mushrooms and plants require this relationship for growth and development. And also many Mushrooms are saprobic, living on decayed various fallen leaves, twigs, trees and vegetable remains and etc. some of these million of spores settles on the proper habitat, these spores germinates and grows into a mass of threads, then a mycelium. This is the vegetable part of the mushrooms, what we call mushrooms are the carpophores, all the characteristics of the morphological features are appropriately used to identify species of mushrooms. Recently, identification and classification of mushrooms are newly confirmed by molecular analysis. In 2013, One thousand nine hundred one species of mushrooms in "List of Mushrooms in Korea" which published by the Korean Society of Mycology were recorded. Total of 238species, 107genera, 40families, 13orders, 6Classes belong to phylum Ascomycota. Total of 1,663species, 403genera 81families, 18orders, 7classes belong to phylum Basidiomycota.

• 한국환경농학회지
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• 제38권4호
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• pp.296-306
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• 2019

온도는 곤충의 발달, 성장, 생식에 중요한 요인이며, 또한 곤충의 생존에 직접적 관련있는 물리적 요인이다. 변온동물인 곤충은 생존을 위해 기후변화에 반응을 해야 하며, 저온과 같은 취약한 환경하에서도 다양한 생존전략을 발달시켜야 한다. 본 연구는 저온에 대한 적응에 기여하는 유전자를 동정하기 위해 배추좀나방 유충의 지방체를 저온과 상온에 노출시켜 전사체 분석을 수행하였다. 저온전사체에서는 chitinase, 표피단백질, Hsp23, chytochrome, Glutathione S transferase, phospholipase 2 유전자의 발현이 증가된 반면, 에너지 대사에 관여하는 UDP-당전이효소, trehalase, trehalose transporter는 오히려 발현이 감소하였다. 저온에 곤충이 노출되었을 때, 대사중심인 지방체의 유전자 발현의 변화가 곤충의 온도 적응을 이해하는 단서를 제공할 수 있을 것으로 기대된다.

• 한국어류학회지
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• 제27권1호
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• pp.33-38
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• 2015

주둥치의 위내용물 분석에 이용된 개체는 총 350개체로 가덕도 주변해역에서 2010년 10월부터 2011년 9월까지 매월 채집하였다. 주둥치의 체장범위는 3.0~9.8 cm를 보였다. 주둥치는 주로 요각류와 게류 유생, 새우류 유생, 갯지렁이류 등을 섭식하는 육식성 어류로 확인되었다. 그 외에 난바다곤쟁이류, 단각류, 이매패류 유생, 복족류 유생 등도 발견되었지만, 그 양은 많지 않았다. 주둥치는 성장함에 따라 주요 먹이생물을 전환하였는데 3~5 cm 사이의 개체들은 요각류를, 5~7 cm 사이의 개체들은 게류 유생과 새우류 유생을, 8~10 cm의 개체들은 갯지렁이류를 주로 섭식하였다. 체장이 증가함에 따라 먹이생물의 무게는 유의하게 증가하였다.

• Molecules and Cells
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• 제39권11호
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• pp.807-813
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• 2016

Escherichia coli are important indicator organisms, used routinely for the monitoring of water and food safety. For quick, sensitive and real-time detection of E. coli we developed a 2'F modified RNA aptamer Ec3, by Cell-SELEX. The 31 nucleotide truncated Ec3 demonstrated improved binding and low nano-molar affinity to E. coli. The aptamer developed by us out-performs the commercial antibody and aptamer used for E. coli detection. Ec3(31) aptamer based E. coli detection was done using three different detection formats and the assay sensitivities were determined. Conventional Ec3(31)-biotin-streptavidin magnetic separation could detect E. coli with a limit of detection of $1.3{\times}10^6CFU/ml$. Although, optical analytic technique, biolayer interferometry, did not improve the sensitivity of detection for whole cells, a very significant improvement in the detection was seen with the E. coli cell lysate ($5{\times}10^4CFU/ml$). Finally we developed Electrochemical Impedance Spectroscopy (EIS) gap capacitance biosensor that has detection limits of $2{\times}10^4CFU/mL$ of E. coli cells, without any labeling and signal amplification techniques. We believe that our developed method can step towards more complex and real sample application.

• Biomolecules & Therapeutics
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• 제12권4호
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• pp.242-249
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• 2004

The main aim of this study was to investigate stress related activities of Sun-ginseng extract as a candidate for anti-stress-related functional supplement by comparing its effect to those of red ginseng, which is also known to alleviate stress. Normal group was not exposed to stress while the control group was exposed to stress. Rats were orally administered once a day with 200 mg red ginseng (RG) extract, 100 or 200 mg Sun-ginseng (SG) extract/kg body weight. Mice were given water containing 400 mg red ginseng extract, 200 or 400 mg SG/100 mL potable water. Rats were given supplements for 5 days without stress, and 5 days with restraint and electroshock stress. After final stress, stress-related behavioral changes of experimental animals were recorded and levels of blood corticosterone were measured. Mice were given supplements for 5 days through drinking water, and then fatigue related motor activity were recorded. SG-supplementation partially blocked stress effect on locomotion and elevated plus maze test in rats, and also partially blocked stress-induced behavioral changes such as freezing, burrowing, smelling, facewashing, grooming and rearing behavior in rats. SG-supplementation decreased blood corticosterone level which is increased by stress in rats. Effects of SG may not be modulated by GABAnergic nervous system. SG-supplementation prolonged swimming time and staying time on the wire and rotarod wheel in mice. These results suggest that SG partially protects living organisms from stress attack in some cases and thus has the potential to be used as a functional food to alleviate stress response.

• The Korean Journal of Ecology
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• 제27권1호
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• pp.15-20
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• 2004

With attention to different human activities around Anzali wetland and introduction of different pollutants containing heavy metals into this water ecosystem and absorption and accumulation of heavy metals in shell and muscle of Astacus leptodactylus which is native benthose of Anzali wetland and enjoys food and economic importance; Sampling of waters and sediments from 18 stations and shell and muscle of Astacus leptodactylus from 5 stations had been conducted. After biometric evaluation of Astacus leptodactylus, the chemical analysis of the samples by using international and standard methods and then their heavy metals content was determined by Atomic Absorpotion Spectrophotometer (AAS), model P.U 9400 philips. Result of the analysis stated that; 1) The mean values of Cr, Zn, Pb, Ni, V in Anzali waters were 6.4, 184.5, 28.8, 28.9, 47.1 ($\mu$ gr/lit) respectively, which comparing to the international standards, is not suitable for drinking, but it can be used for agricultural and aquacultural purposes. Even though the concentration of heavy metals in sediments were high, there are in range of acceptable limit for aquatics organisms; 2) Comparatively, the concentration of heavy metals in shell and muscle of Astacus leptodactylus in Anzali wetland (Cr, Zn, Pb, Ni, V in shell were 3.48, 109.3, 14.13, 7.17, 36.2 and in muscle were 2.98, 131.98, 3.12, 4.77, 9.05 ppm respectively) were more than what is determined for Aras dam (in shell were 1.6, 224.3, 7.8, 7.6, 10.3 and in muscle were 1.4, 60.2, 0.45, 2.7, 4.4 mg/kgr respectively); 3) For all samples, concentration of heavy metals in all Astacus leptodactylus in Anzali wetland and Aras dam, was at tolerance level for human consumption; 4) There was no association with significant difference between weight and size of Astacus leptodactylus with absorption and accumulation of heavy metals; but there was a significant association between heavy metals content in water and in sediments, and in sediments, shell and muscle of Astacus leptodactylus in Anzali wetland.

• 대한미생물학회지
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• 제11권1호
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• pp.33-48
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• 1976

The practical significance of using a selective enrichment procedure for detecion and enumeration of salmonella is well recognized. There are still various selective enrichment media has been communly used. Early years selenite broth was recomnended as an enrichment media for the isolating of salmonella. Hajna introduced a modified tetrathionate broth and demonstrated the greater efficiency to compare with the previous enrichment media. Raj also described that the new medium called dulcitol selenite enrichment and has been found to be very satisfactory, especially general implication in food poisoning. Authors tried to compare these 3 enrichment media for isolating salmonella. 1. When salmonella strains were inoculated $1{\sim}10^6$ cells per tube to these 3 enrichment media, mostly similar results were obtained between selenite broth and DS broth. In these 2 enrichment broth were showed $10^7/ml-10^8/ml$ cells of all tested salmonella strains. But in the case of TT broth it was found that the growth was $10^3/ml{\sim}10^4/ml$ cells for tested strain. 2. When E. coli, Proteus, Citrobacter were inoculate $10{\sim}10^6$ cells per tube to these 3 enrichment media. It was suggested that DS broth was showed more inhibitory action than that of selenite broth. TT broth showed high inhibition to these 3 organisms tested. 3. It was generally known that the incubation time is influenced to the frequency of salmonella detection. For this tendency, DS broth and selenite broth were showed similar results within 24 hrs to 48hrs incubation to the test. But DS broth showed more inhibitory action to E. coli and Proteus than that of selenite broth. 4. When $1{\sim}10$ cells were inoculated(per tube) to these 3 enrichment media, DS broth was found to be more sensitive than that of selenite broth.