• 대한수의학회지
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• 제31권4호
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• pp.491-500
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• 1991

This study was conducted to detect the serum antibodies in the experimentally toxoplasma infected dogs and street dogs by use the of an enzyme-linked immunosorbent assay (ELISA). And this test was performed on the polystylene microplate by coating with the tachyzoites soluble antigen of T gondii (RH strain), incubated with sera diluted then, added with HPO-conjugated rabbit anti-dog IgG and o-phenylenediamine used as a substrate. Tachyzoites of T gondii harvested from mouse peritoneal cavity were purified by 30, 40 and 50% Percoll density gradient centrifugation and used as the source of antigen. The results obtained were summarized as follows; 1. The highest ratio of positive to negative (P/N ratio) was obtained at the level of $l{\mu}g/ml$ protein concentration of antigen with the 1/4000 dilution of the conjugate measured by checker-board titration. It was regarded as the optimum concentration of the antigen and conjugate. 2. Cut-off value in this IgG ELISA was 0.375 that was determined by mean absorbance (at 492nm) of IFA negative serum added with the dauble value of the standard deviation $(mean{\pm}2S.D.)$. 3. Serum ELISA IgG antibodies to T gondii in the exyerimentally infected dogs were detected firstly at the Week 3 after inoculation and the highest titer was recognized at the Week 4, 5 and 6 after inoculation. 4. Stability of the antigen absorbed in the microplates that were preserved at $4^{\circ}C$ and $-25^{\circ}C$ separately were prolonged up to 3 weeks and 10 weeks at $4^{\circ}C$ and $-25^{\circ}C$, respectively. However the reproducibility was not reliable after the preservation of 4 weeks and longer. 5. Positive rate of the specific antibodies in 312 test sera was 28.5% and there was no significant differences between the male (27.8%) and female (29.5%), respectively. 6. The IgG ELISA was proved to be a specific procedure for the detection of antibodies to canine toxoplasma infection and also evaluated as a screening test for the large scale of test samples in laboratory.

• 한국식품위생안전성학회지
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• 제25권3호
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• pp.215-219
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• 2010

본 연구는 섬오갈피 뿌리 추출물을 이용하여 돌연변이 유발을 관찰하기 위해 S. typhimurium TA100, TA98, TA1535, TA1537과 E. coli WP2 uvr A를 이용해 Ames test을 하였고 또한 S. typhimurium TA100, TA98을 이용한 항돌연변이원 억제 시험을 시행하였다. Ames test에 필요한 시험물질들은 최고농도 결정을 통해 $5000\;{\mu}g$/plate, $2500\;{\mu}g$/plate, $600\;{\mu}g$/plate의 시험물질을 양성대조군, 실험군, 음성대조군을 비대사활성계와 대사활성계로 나누어 시험을 시행하였다. 시험 결과 모든 농도에서는 집락군의 일관성 있는 증가는 보이지 않았고 이 점으로 미루어 보아 복귀돌연변이는 일어나지 않았고 음성으로 판정하였다. 항돌연변이원 시험에서는 양성물질의 농도결정과 시험물질의 최고농도 결을 통해 양성대조군, 실험군, 음성대조군을 비대사활성계와 대사활성계로 시험을 하였고 시험결과 S. typhimurium TA100, TA98 두 균주 돌연변이 억제를 보였으며 TA98에서 더 높은 억제율을 보였다. 시험결과로 섬오갈피의 뿌리는 항돌연변이 억제효과에 탁월한 효과가 있음을 시사하였다.

• 한국환경성돌연변이발암원학회지
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• 제8권1호
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• pp.13-21
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• 1988

Mutagenic actions of aflatoxin B$_1$ (AFB$_1$) in the presence of various concentrations of L-ascorbIc acid (AA) in Salmonella typhimurium strains TA 100 and TA98 were studied. Spontaneous revertants per plate of the tester strains TA100 and TA98 were 121-125 and 25-30 with or without S9 mix, respectively. The negative controls used in the study did not show any mutagenesis in the tester strains. AFB$_1$ revealed strong mutagenicity at the dose levels of 0.05, 0.1 and 0.25 ${\mu}$g/plate with metabolic activation system in both strains. However, it showed a toxic effect when the levels were more than 0.5 ${\mu}$g/plate. When lower concentrations of AA (5-20 ${\mu}$g/plate) were added to AFB$_1$ in the Ames assay system with S9 mix the mutagenic action of AFB$_1$ decreased in both strains. About 70-90% of mutagenicity of AFB$_1$ disappeared in strain TA100 when 20${\mu}$g of AA was added to 0.05 ${\mu}$g of AFB$_1$. The inhibitory effect was greatly increased by the addition of higher concentrations of AA to AFB$_1$ in TA100 strain. The mutagenicity of AFB$_1$ was completely inhibited when 100 ${\mu}$g and 500 ${\mu}$g of AA were added to 0.05 ${\mu}$g and 0.1 ${\mu}$g of AFB$_1$, respectively, However, this protective effect of AA on AFB$_1$ mediated mutagenesis was less effective in TA98 strain than that in TA100.

• 대한지역사회영양학회지
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• 제5권2호
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• pp.152-160
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• 2000

The purpose of this study was to investigate zinc and copper metabolism and risk factors of chronic diseases in 20 normal adults women. The daily intake, excretions in urine and feces, and serum levels of zinc and copper were determined by 24-hr food records and chemical analysis. The results were summarized as follows. mean age, body weight and BMI were 22.88 years, 54.65kg and 21.28kg/$m^2$ respectively. Mean daily intakes of energy and protein were 1578.84㎉(79% of RDA) and 52.05g (87% of RDA). The zinc and copper intake, excrestion in urine and feces were 7093.23$\mu\textrm{g}$(59% of RDA/2093.87$\mu\textrm{g}$, 203.50$\mu\textrm{g}$/39.87$\mu\textrm{g}$ and 3416.41$\mu\textrm{g}$/857.62$\mu\textrm{g}$, respectively. The serum levels of fasting glucose, insulin, total cholesterol, HDL-cholesterol, LDL-cholesterol, triglyceride, zinc and copper were 76.60mg/㎗, 15.66IU/㎗, 160.30mg/㎗, 50.95mg/㎗, 89.80mg/㎗, 89.79mg/㎗, 95.65$\mu\textrm{g}$/㎗ and 73.28$\mu\textrm{g}$/㎗ respectively. Dietary ratio of Zn to Cu was shown to have significant positive correlations with serum insulin, total cholesterol, LDL-cholesterol. The urinary ratio of Zn to Cu was shown to have significant positive correlations with triglyceride. The serum copper level was shown to have significant negative correlations with serum total cholesterol and LDL-cholesterol. In summary, Zn consumption of adult women in their normal diet does not meet the Zn requirement for Koreans. Also, intakes of Zn and Cu may effect the glucose metabolism and cardiovascular diseases. Therefore, to increase the Zn intake and to maintain an appropriate intake ratio of Zn to Cu, nutrition education needs to be implemented.

• Annals of Laboratory Medicine
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• 제39권1호
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• pp.50-57
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• 2019

Background: The Automated Fluorescent Immunoassay System (AFIAS) rotavirus assay (Boditech Med Inc., Chuncheon, Korea) is a new rapid antigen test for rotavirus detection. We evaluated the performance of this assay for detecting rotaviruses and their specific genotypes in clinical stool samples. Methods: AFIAS rotavirus assay was performed in 103 rotavirus-positive and 103 rotavirus-negative stool samples (confirmed by both PCR and ELISA), and its results were compared with those of PCR, ELISA, and immunochromatographic assay (ICA). We evaluated diagnostic sensitivity/specificity, the detectability of rotavirus subtypes, lower limit of detection (LLOD), reproducibility, cross-reactivity, and interference of AFIAS rotavirus assay. Results: Based on PCR and ELISA results, diagnostic sensitivity and specificity of the AFIAS rotavirus assay were both 99.0%. LLOD results showed that the AFIAS assay had sensitivity similar to or greater than ICA and ELISA. High reproducibility was confirmed, and no cross-reactivity or interference was detected. This assay could detect genotypes G1P[8], G2P[4], G3P[8], G4P[6], G4P[8], G8P[4], G8P[8], G9P[4], and G9P[8]. Conclusions: The AFIAS rotavirus assay showed high reproducibility, sensitivity, and specificity as well as excellent agreement with ELISA, PCR, and ICA. It detected the most common as well as unusual genotypes of rotavirus prevalent in Korea. It could be a useful onsite assay for rapid, convenient, and cost-effective detection of rotavirus infection.

• Journal of Microbiology and Biotechnology
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• 제18권3호
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• pp.545-551
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• 2008

When cultivated aerobically, Aspergillus niger hyphae produced extracellular glucoamylase, which catalyzes the saccharification of unliquified potato starch into glucose, but not when grown under anaerobic conditions. The $K_m\;and\;V_{max}$ of the extracellular glucoamylase were 652.3 mg/l of starch and 253.3 mg/l/min of glucose, respectively. In mixed culture of A. niger and Saccharomyces cerevisiae, oxygen had a negative influence on the alcohol fermentation of yeast, but activated fungal growth. Therefore, oxygen is a critical factor for ethanol production in the mixed culture, and its generation through electrolysis of water in an electrochemical bioreactor needs to be optimized for ethanol production from starch by coculture of fungal hyphae and yeast cells. By applying pulsed electric fields (PEF) into the electrochemical bioreactor, ethanol production from starch improved significantly: Ethanol produced from 50 g/l potato starch by a mixed culture of A. niger and S. cerevisiae was about 5 g/l in a conventional bioreactor, but was 9 g/l in 5 volts of PEF and about 19 g/l in 4 volts of PEF for 5 days.

• 한국식품위생안전성학회지
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• 제10권2호
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• pp.103-109
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• 1995

Microbiological and organoleptic qualities of boiled anchovies were evaluated during storage for 8 months at different temperatures and packaging methods. Microbial populations of marketing samples were 106~107 CFU/g in aerobic bacteria, 103~106 CFU/g in yeasts/molds and 103~105 CFU/g in coliforms, respectively, which were the highest in retail sample, followed by in military goods and wholesale sample. Moreover, anchovies supplied for retail sale and military goods were contaminated with sanitary indicative microbes. The samples stored at ambient condition(15~33$^{\circ}C$, RH 5$0^{\circ}C$95%) lost their marketable quaity mainly due to microbial propagation prior to 6 months, irrespective of packaging methods, corrugated-cardboard box and laminated-film(nylon 15${\mu}{\textrm}{m}$/PE 100${\mu}{\textrm}{m}$). However, cooling(5~1$0^{\circ}C$) as well as well as freezing temperatures($\leq$-18$^{\circ}C$) following laminated-film packaging were effective for keeping the organoleptic qualities of stored anchovies up to 8 months. The population of yeasts and molds was shown the quality-indicative criteria for stored anchovies and their critical levels were 5.00 log counts/g, showing a higher negative-correlationship(r=-0.901) with changes in organoleptic quality.

• Journal of Nutrition and Health
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• 제36권9호
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• pp.942-949
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• 2003

This study was longitudinally conducted to evaluate the intakes of protein, Ca, Mg and P of exclusively breast-fed infants compared with the Recommended Dietary Allowances (RDA) for Korean infants. Twenty Korean lactating women and their infants during the first 3 months of lactation in Incheon area were participated. Protein, Ca and Mg, and P contents in the milk were determined using semimicro Kjeldahl (N ${\times}$ 6.38) , atomic absorption spectrophotometer and colorimeter, respectively, and also the milk consumption of the infants was measured by the test-weighing method. Protein contents of the milk were 1.96, 1.63, 1.51, 1.25 and 1.16 g/100 ml, and protein intakes of the breast-fed infants were 9.00, 9.85, 9.17, 8.97 and 7.76 g/day at 7, 15, 30, 60 and 90 days postpartum. The average protein intake per body weight of the breast-fed infants was 1.84 g/kg/day. The average intakes of Ca, Mg, P were 172.1 mg/day, 15.2 mg/day and 91.4 mg/day, respectively, and the average Ca/P ratio was 1.91. There was positive correlation between protein and Ca, protein and p, and Ca and P contents while negative correlation between Mg and P, The body weight of breast-fed infants increased normally from 3.6 $\pm$ 0.41 g at birth to three month during lactation. It is suggested that the breast-fed infants in Incheon area consume almost adequately protein, Ca and P from the milk compared with RDA for Korean infants.

• 한국미생물·생명공학회지
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• 제10권3호
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• pp.171-175
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• 1982

항균 활성이 대체로 상승되었으나 Sarcina maginata의 경우는 약간 감소되었다. $\beta$-lactam 항생 물질인 penicillin G.Na와 ampicillin.Na도 인삼 saponin의 첨가로 항균 활성이 상승되었으나 Serratia 속 세균은 penicillin G.Na의 항균활성에 일정한 효과를 나타내지 않았다. 인삼 saponin 의 첨가에 의한 항생 물질들의 항균 활성의 변화는 Gram양성 세균 및 Gram음성 세균에 대해 일정하지 않은 상승 작용 혹은 길항작용과 같은 비특이성을 나타내었다. 세균의 약제 내성 현상도 인삼 saponin자 항생물질의 투여로 배제될 수 있을 것으로 사료되었다.

• 상하수도학회지
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• 제23권1호
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• pp.113-119
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• 2009

The feasibility of using cork oak bark for phosphorus removal from wastewater was evaluated in this study. Recently, development of more cost-effective media while maintaining high efficiency in pollutants removal has received concern. Barks have a negative surface charge and, hence, tend to show a high affinity to bind cations, and they need to undergo chemical modification to increase their adsorption capacity of anions. Bark was hydrolyzed by HCl solution and it received modification using an aqueous solution of high molecular weight polyethylenimine(PEI). Surface modification with HCl and PEI resulted in a decrease of specific surface area of the bark from $1.932 m^2/g$ to $1.094 m^2/g$. The adsorption experiments were carried out in batch tests and the data were fitted to the Langmuir isotherm and Freundlich isotherm equations. Phosphate removal rate was higher at the lower solution pH possibly due to the form of phosphate ion in solution. For the initial phosphate concentration of 10 mg/L, maximum adsorption was 20.88 mg P/g at pH 3 and 12.02 mg P/g at pH 5. Mechanism of phosphorus sorption onto the HCl-PEI bark was examined through FT-IR spectrometer. Ion exchange between $NH^+$ and $H_2PO_4{^-}$ appeared to be a key mechanism of phosphate adsorption onto the HCl-PEI bark surface.