• 한국미생물학회:학술대회논문집
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• 한국미생물학회 2003년도 International Meeting of the Microbiological Society of Korea
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• pp.13-15
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• 2003

Studies on marine microbial diversity using direct analysis of rRNA sequences have revealed previously unrecognized microbes and novel phylogenetic lineages that represent major components of global microbial assemblages. This diversity in the marine biosphere offers opportunities for research and application in the field of biotechnology; global gas exchange, nutrient and element cycling, biomass md food production, marine bioproducts, and bioprocesses. Especially, deep-sea encompasses the extremes of virtually at] environmental parameters found on Earth and provides extreme microorganisms. In this study several extreme microorganisms were successfully isolated from the deep-sea sediment samples obtained by joining ocean cruises for last 2 years and some of them will be introduced.

• 식품과학과 산업
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• 제54권4호
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• pp.278-292
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• 2021

Fermented milk including yogurt, which has a long tradition of thousands of years, was first established in Korea in 1919, and the current market size has grown to over 90 billion dollars. Fermented milk, which began in the early days of liquid yogurt, appeared on the market as spoonable and drinking yogurt. Fermented milk began with research on intestinal health functions and lactobacilli, and gradually developed into various disease prevention studies such as gastrointestinal health, immunity improvement, skin beauty, and prevention of dementia. As a simple meal, it has a nutrient function element, which serves as a meal replacement, and is expanding its range from general foods to special-purpose foods and dietary supplements. Fierce market competition is taking place, and as a result, the domestic fermented milk market is developing through the development of various products for differentiation.

• 한국작물학회지
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• 제48권
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• pp.13-23
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• 2003

The trace mineral, selenium (Se), is an essential nutrient of fundamental importance to human health. It is also very toxic and can cause Se poisoning (selenosis) in human and animals when its intake exceeds a suitable amount. Se functions within mammalian systems primarily in the form of solenoprotein. About 35 selenoproteins have been identified, though many have not yet been fully elucidated. Selenoproteins contain Se as selenocyseine (Sec) and perform variety of structural and enzymic roles; the enzymic roles are best-known as the antioxidants for hydrogen peroxides and lipid peroxides, and the catalysts for production of activity thyroid hormone. Glutathione peroxidases ($\textrm{GP}_X$) among the selenoproteins prevent the generation of free radicals and decrease the risk of oxidative damage to tissues, as does thioredoxin reductase (TR). TR also provides reducing power for several biochemical processes. Selenoproteins P and W are involved with oxidant defense in plasma and muscle, respectively, A selenoprotein is also required for sperm motility and may reduce the risk of miscarriage. Some epidemiological studies have revealed an inverse correlation between Se status and cardiovascular disease, and there is considerable evidence 1mm population com-parison data and animal studies that Se is anticarcinogenic. It is also suggested that Se should be needed for the proper functioning of the immune system, and appear to be a key nutrient in counteracting the development of virulence and inhibiting HIV progression to AIDS. As research continues, the role of selenium in the etiology of chronic diseases like appropriate medical nutrition therapy can be delivered and its effectiveness assessed. Se status in individuals is affected by diet and the availability of the Se. The Se content of plants is affected by the content and availability of the element in the soil in which they are grown, and so greatly varies from country to country, while the Se composition of meat reflects the feeding patterns of livestock. This paper provides an overview on Se as an essential trace mineral for human.

• 환경생물
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• 제24권4호
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• pp.408-415
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• 2006

Serpentines soil have high values of magnesium and low values of calcium, and are usually deficient in N and P, but rich in iron, Ni, silicates. We investigated serpentine soil properties and measured the content of nutrient elements and heavy metals in shoots and root of plant species which were in common at serpentine and non-serpentine areas in Andong, Korea. The soils showed higher pH value above 6.9. The contents of Ni, Cr, Fe and Mg of serpentine soils exhibited 77, 27, 5.5 and 12.5 times more than in non-serpentine soils, respectively. The content of Na was almost same but K was two times higher in non-serpentine soil, compared with serpentine soil. The contents of nutrient element such as K, Ca, Na and P in serpentine plants did not show conspicuous differences with non-serpentine plants. On the other hand, the concentrations of Ni, Cr, Fe, Mg and Mg/Ca were very high in plant on serpentine area. The all plant species collected at the serpentine site were bodenvag plants, which are not restricted to a specific type of substrate. By the plant species and parts of plant tissues, the absorption levels and patterns showed high variation and were species-specific. Carex lanceolata, Lysimachia clethroides and Cynanchum paniculatum contained much chromium and Eupatorium chinense and C. paniculatum exhibited high contents of Ni. In leaf tissue, C. lanceolata, Rubus parvifolius, Festuca ovina, Quercus serrata, and L. clethroides took comparatively large amount of Cr in serpentine area. E. chinense contained large amount of Ni, Cr and Fe in a leaf tissue. The stem of Galium verum, Juniperus rigida included high amount of Cr, Ni and Fe. And C. paniculatum absorbed large amount of Ni and Cr in the stem.

• 한국환경농학회지
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• 제16권3호
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• pp.216-219
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• 1997

작물의 방사선 감수성에 대한 영양결핍 효과를 구명하고자 몇 가지 양분이 결핍된 영양액으로 사경 재배한 수도 유식물체에 ${\gamma}$선을 조사하고 30일간 재배하여 그 생육상태를 조사한 결과는 다음과 같다. 양분 결핍으로 재배된 수도 유식물체는 양분 전량 첨가된 대조구에 비해 초장과 생체중이 크게 감소되어 방사선 감수성이 증가됨을 보였다. 그 효과는 영양소와 수도 품종에 따라 다르게 나타났는데 일품벼에서는 철결핍이, 태백벼에서는 인산 결핍이 유의성 있는 방사선 감수성 증가효과를 보였다. 방사선 조사량에 따른 효과는 저선량인 20Gy 조사구의 경우 일품벼는 철과 아연 결핍구가, 태백벼에서는 인산과 아연결핍구가 생장 저해가 높았으나, 80Gy 조사구에서는 일품벼와 태백벼 모두 인산과 칼슘결핍구가 방사선 감수성이 높았다.

• Journal of Nutrition and Health
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• 제55권4호
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• pp.441-449
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• 2022

This review is focused on analyzing the limits and shortage of zinc (Zn) for the 2020 Dietary Reference Intakes for Koreans (KDRIs), and provides suggestions for the future establishment of the 2025 KDRIs for Zn. The 2020 KDRIs for Zn have been established to estimate the adequate requirement (EAR), recommended nutrient intakes (RNI), adequate intake (for only 0-5 mon) and tolerable upper intake level (UL). EAR was estimated in 2-stages: the first stage was to construct of the frame of analysis for Zn requirement and the second stage involved a factorial approach by considering the various factors which affect Zn requirement, such as intestinal and urine Zn loss, Zn requirement for growth and development, and Zn absorption rate. For a more precise and accurate establishment of the Zn requirement, we suggest for the following to be considered: 1) considering that Zn is present in minuscule amounts as a trace element in our body, the present values for Zn EAR (as 6-9 mg/d) should be expressed as a decimal point for more accurate DRIs; 2) the frame of analysis for Zn requirement has to be more specifically and should includes the factors which affect Zn requirement; 3) both, the factorial approach and extrapolation method need to be well reviewed and thoroughly understood for establishing precise Zn requirement; 4) currently, human clinical study and balance study (Zn intake, excretion and absorption rate) are limited and more human Zn subject studies are required. All these suggestions are provided to better establish the Zn requirement in the 2025 KDRIs.

• 생물환경조절학회지
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• 제28권1호
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• pp.38-45
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• 2019

순환식 수경재배 시스템을 이용한 배액의 재활용은 수자원 및 생산비 절감, 환경오염 방지를 위하여 중요하다. 따라서 일반 토마토인 'Bonus'를 110일간 반촉성 수경재배하면서 생육 단계별 식물체, 공급액 및 배액의 무기원소 농도 분석을 통하여 순환식 수경재배 시스템 개발을 위한 기초 자료를 확보하고자 본 연구를 수행하였다. 착과절위에 따른 엽의 T-N 함량은 생육 초기에 약 4.1%로 높았으나 생육 후기로 갈수록 낮아져 8화방 개화기에는 3.9%로 낮아졌다. P 함량은 초기에 높았으며, 3-7화방까지는 비슷하였고, 8화방에서 낮았다. Ca, Mg 및 Na은 생육초기보다 후기로 갈수록 함량이 높아져 8화방 개화기에 가장 높았다. 토마토 생육 기간이 경과할수록 공급 양액과 배액의 $NO_3-N$, P, K, Ca 및 Mg 농도는 정식 5주 후까지의 생육 초기에는 비슷하였으나 생육 후기로 갈수록 공급액보다 배액에서 농도가 높아지는 경향이었다. B, Fe 및 Na의 경우 생육 초기에는 배액의 농도가 약간 높았으며 중기 이후부터 공급액보다 배액의 농도가 높았다. 이상의 결과는 토마토 순환식 반촉성 수경재배 시 배액의 무기원소 농도를 교정하기 위한 기초 자료로 활용될 수 있을 것이다.

• Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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• 제2권2호
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• pp.169-179
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• 1998

This paper was performed to estimate interrelations between humus level of sediments and nutrient release from sediments in Dae-cheong reservoir. For investigations, sediments were sampled in June and October, in 1997 at fish farms, embayment, and the main stream of Dae-cheong reservoir. Items for investigation are as follows; water content, weight loss on ignition(IG), porosities of sediments, contents of element such as hydrogen, nitrogen, carbon, and nutrient release rates. Water contents and porosities were measured to conjecture the physical trait and grain size trait. Weight loss on ignition was measured to determine the contents of organic substance. For determination of the humus level of sediments, carbon and nitrogen contents were measured by elemental analyzer. As a result of elemental analysis, C/N ratio was determined in the range of $3.0\~13.1$. From the elemental analysis, humus level of Dae-cheong reservoir sediment was estimated from mesohumic state to oligotrophic state. For the determination of nutrient release rate, $PO_4-P$ and $NH_4-N$ concentrations of interstitial water and overlying water were measured. By using the concentration difference between interstitial water and overlying water and using the Fick's diffusion law, the release rates of phosphorus and nitrogen from the sediment samples were calculated. Release rates of nutrients which directly influence to the water quality were $0.05\~8.63mgP/m^2day$ and $4.99\~36.56mgP/m^2day$. It was found that release rate was measured higher in the 1st sampling period than in the 2nd sampling period. For the determination of phosphorus content in sediment, TPs were measured in 807\~1542{\mu}g/g$ in the 1st samling period and $677\~5238{\mu}g/g$ in the End samling period. Phosphorus release rate and phosphorus content were not interrelated each other.

• 한국식물병리학회지
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• 제11권4호
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• pp.304-311
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• 1995

To determine whether chitinolytic enzymes from Chromobacterium violaceum C-61 play an important role in the suppression of Rhizoctonia damping-off, Tn5 insertion mutants deficient in chitinolytic activity (Chi a- mutants) were selected and their chitinolytic and disease suppression were compared with those of the parental strain. Four Chi a- mutants selected from about 2,000 transconjugants did not inhibit mycelial growth of Rhizoctonia solani on nutrient agar-potato dextrose agar (BA-PDA) and their abilities to suppress Rhizoctonia damping-off were much lower than the parental strain. However, population density in the eggplant rhizosphere did not differ significantly between the parental strain and four Chi a- mutants. The crude enzyme of the parental strain inhibited growth of R. solani on NA-PDA and its chitinase activity was much higher than that of Chi a- mutants. But the N,N' -diacetylchitobiase activity between these isolates were not significantly different. The chitinase of Chi a- mutants was defective in 2 isoforms of 52- and 37-kDa among four isoforms of 54-, 52-, 50- and 37-kDa. A Tn5 element was inserted into one site of 10 kb EcoRI fragment of chromosomal DNA in three Chi- mutants, C61-C1, -C2, and -C3. In C61-C4 mutant, a Tn5 element was inserted into two sites of 10 kb and 4.4 kb EcoRI fragments. These results suggest that the chitinase of C. violaceum C-61 play an important role in the suppression of Rhizoctonia damping-off of cucumber and eggplant.

• The Plant Pathology Journal
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• 제36권5호
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• pp.398-405
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• 2020

Nutrient manipulation is a promising strategy for controlling plant diseases in sustainable agriculture. Although many studies have investigated the relationships between certain elements and plant diseases, few have comprehensively explored how differing mineral nutrition levels might affect plant-fungal pathogen interactions, namely plant susceptibility and resistance. Here, we systematically explored the effects of the seven mineral elements that plants require in the greatest amounts for normal development on the susceptibility of soybean plants (Glycine max) to Fusarium oxysporum infection in controlled greenhouse conditions. Nitrogen (N) negligibly affected plant susceptibility to infection in the range 4 to 24 mM for both tested soybean cultivars. At relatively high concentrations, phosphorus (P) increased plant susceptibility to infection, which led to severely reduced shoot and root dry weights. Potassium (K), calcium (Ca), magnesium (Mg), sulfur (S), and iron (Fe) induced plant resistance to infection as their concentrations were increased. For K and Ca, moderate concentrations had a positive effect on plant resistance to the pathogen, whereas relatively high doses of either element adversely affected plant growth and promoted disease symptoms. Further experiments were conducted, assessing disease suppression by selected combinations of macro-elements and Fe at screened concentrations, i.e., K (9 mM) plus Fe (0.2 mM), and S (4 mM) plus Fe (0.2 mM). The disease index was significantly reduced by the combination of K plus Fe. In conclusion, this systematic investigation of soybean plant responses to F. oxysporum infection provides a solid basis for future environmentally-friendly choices for application in soybean disease control programs.