• Journal of Environmental Science International
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• v.32 no.1
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• pp.57-65
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• 2023

The advanced oxidation treatment using persulfate and zero-valent iron (ZVI) has been evaluated as a very effective technology for remediation of soil and groundwater contamination. However, the high rate of the initial reaction of persulfate with ZVI causes over-consumption of an injected persulfate, and the excessively generated active species show a low transfer rate to the target pollutant. In this study, ZVI was modified using selenium with very low reactivity in the water environment with the aim of controlling the persulfate activation rate by controlling the reactivity of ZVI. Selenium-modified ZVI (Se/ZVI) was confirmed to have a selenium coating on the surface through SEM/EDS analysis, and low reductive reactivity to trichlroethylene (TCE) was observed. As a result of inducing the persulfate activation using the synthesized Se/ZVI, the persulfated consumption rate was greatly reduced, and the decomposition rate of the model contaminant, anisole, was also reduced in proportion. However, the final decomposition efficiency was rather increased, which seems to be the result of preventing persulfate over-consumption. This is because the transfer efficiency of the active species (SO4-∙) of persulfate to the target contaminant has been improved. Selenium on the surface of Se/ZVI was not significantly dissolved even under oxidation conditions by persulfate, and most of it was present in the form of Se/ZVI. It was confirmed that the persulfate activation rate could be controlled by controlling the reactivity of ZVI, which could greatly contribute to the improvement of the persulfate oxidation efficiency.

• Bulletin of the Korean Chemical Society
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• v.34 no.12
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• pp.3767-3770
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• 2013

Potassium methylselenite ($KSeO_2(OCH_3)$) was reduced to elemental selenium, Se(0), and then doped onto montmorillonite K 10 (MK10) clay to examine the interaction between elemental mercury (Hg(0)) vapor and Se(0) in an effort to understand the possible heterogeneous reaction of Hg(0) vapor and Se(0) solid. The clay was used as a cost-effective support material for uniform dispersion of Se(0). The Se(0)-doped MK10 showed an excellent reaction performance with Hg(0) under an inert nitrogen gas at 70 and $140^{\circ}C$ in our lab-scale fixed-bed system. However, the precursor, $KSeO_2(OCH_3)$-doped MK10 showed a negligible reaction performance with Hg(0), suggesting that the oxidation state of selenium plays a key role in the reaction of Hg(0) vapor and selenium compounds.

• 한국수산학회:학술대회논문집
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• 2005.05a
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• pp.47-48
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• 2005

• The Korean Journal of Soil Zoology
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• v.9 no.1_2
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• pp.32-43
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• 2004

Herein, 15 species of the ground beetles are reported from Jejudo. Of these, 4 species, Bradycellus subditus (Lewis,1879), Colpodes rubriolus Bates, 1883, Pentagonica angulosa Bates, 1873, and Porotachys recurvicollis(Andrewes, 1925) are listed for the first time from the Korean Peninsula. The Korean tachyine species are briefly discussed.

• 한국균학회소식:학술대회논문집
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• 2014.05a
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• pp.30-30
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• 2014

We isolated various yeasts from wild flowers in main islands, Jejudo, Ulleungdo and Yokjido of Korea and their yeasts were identified by comparison of their PCR-amplified D1/D2 regions of 26S rDNA using the BLAST database. Thirty two yeast strains of fourteen species were isolated from wild flowers of Jejudo. Forty eight yeast strains of twenty two species were isolated and identified from wild flowers of Ulleungdo, Korea. Sixty yeast strains belonged to twenty five species were isolated identified from wild flowers of Yokjido in Tongyeong, Korea. Only Metschnikowia reukaufii was overlapped from the three different islands areas. Two species overlapped from Jejudo and Ulleungdo: Pichia guilliermondii, Metschnikowia reukaufii. Seven species were overlapped from Ulleungdo and Yokjido: Cryptococcus albidus, Cryptococcus laurentii, Metschnikowia reukafii, Pichia scolyti, Rhodotorula glutinis, Rhodotorula graminis and Rhodotorula mucilaginosa. Four species were overlapped from Jejudo and Yokjido: Candida sp. Cryptococcus aureus, Metschnikowia reukafii and Pseudozyma sp.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.435-444
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• 2003

In 1957, Schwarz and Foltz discovered that selenium (Se) was an essential trace mineral and nutritionists then started extensive studies to figure out the metabolic function of this element which has been called as toxic mineral. The discovery that glutathione peroxidase (GSH-Px) contained Se demonstrated a biochemical role for Se as an essential trace element. The major physiological function of Se containing GSH-Px is thought to maintain low levels of $H_2O_2$ and other hydroperoxides in the cell to prevent tissues from peroxidation damages. It is known that the GSH-Px activity is increased when animals were fed high dietary levels of Se. Chemical properties of Se have much in common with sulfur (S) therefore Se would follow the sulfur pathways in its metabolism in animal body. Two sources of Se are available for supplementation of Se in animal feed. Inorganic Se can also exist in selenide (-2), elemental (0), selenite (+4) and selenate (+6) oxidation state with other minerals. When sulfur in S containing amino acids is replaced by Se, organic Se can be made and named "eleno"prior to the name of S containing amino acid, i.e. selenomethionine. Selenium deficiency affects humans as well as animals and dysfunctions such as exudative diathesis, retained placenta, mastitis, liver necrosis, Keshan disease, numerous diseases and cancer. From several centuries ago, Se toxicity was recognized in various animal species and much of the current toxic Se levels has been established largely based upon the controlled toxicity studies used inorganic Se. Toxic effects of Se in animal result in reduced feed intake, growth retardation, ataxia, diarrhea, alopecia and sloughing of hooves. However, several experiments demonstrated that Se deficiencies or toxicities were varied by dietary Se levels and sources. Recent studies demonstrated that the incidence of colorectal and prostate cancer was reduced by approximately 50% when humans consumed 200 ${\mu}g$ of Se daily.

• Journal of Applied Biological Chemistry
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• v.66
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• pp.250-257
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• 2023

Glutamate is an excitatory neurotransmitter distributed in the central nervous system of mammals. However, high concentrations of glutamate are known to cause neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and stroke by causing nerve cell death. In this study, the antioxidant activity and neuroprotective effect of subtropical natural products were analyzed. Among 11 subtropical plant extracts mainly tested, Sallacca wallichiana extract (SE) showed the greatest free radical scavenging activity. Then, we confirmed through WST-1 assay that SE protected HT22 cells against glutamate-induced cell death in a concentration-dependent manner. The protective effects of SE against glutamate-induced apoptosis in HT22 cells were also confirmed by flow cytometry analysis using Annexin V/PI double staining. We also confirmed using H₂DCF-DA single staining that SE inhibits glutamate-induced intracellular reactive oxygen species. And we were confirmed through that SE inhibited glutamate-induced phosphorylation of Mitogen-activated Protein kinases. Consequently, our results propose that SE may contribute to the development of therapeutics to prevent neurodegenerative diseases.

• Journal of Ecology and Environment
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• v.31 no.3
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• pp.225-232
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• 2008

To find out the status and characteristics of exotic plants in the Gwangreung Forest, a representative forest ecosystem in central Korea, we surveyed the species composition, coverage, and habitat illuminance of exotic plant species in a set of quadrats established along roads and trails in and around the Gwangreung Forest and buffer zone areas, In 1932, only five species of exotic plants were found along paths and roads in the Gwangreung Forest. However, the number of species in the forest has dramatically increased since 2000, when Ambrosia artemisiifolia L. and A. trifida L. were first recorded, and in 2007, 38 species of exotic plants were recorded. Among the 11 families, 23 genera and 25 species of exotic plants recorded in the quadrats, Compositae was the most common family (11 species), and perennial herbs, 42%, were the most frequently occurring life type, followed by annual herbs (31%) and biennial herbs (19%). Plants of North American origin comprised 48% of exotic species identified in our surveys. Exotics were found most frequently in quadrats along roads in the forest, followed by the buffer zones and hiking trails. The number of species and individuals of exotic plants decreased as we moved deeper into the forest, but Aster pilosus Willd. and Erigeron annuus (L.) Pers. were identified along hiking trails in the interior, and appeared to be capable of spreading further and more rapidly into the forest than other species.

• Journal of Korean Society on Water Environment
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• v.29 no.1
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• pp.114-126
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• 2013

The purpose of this study was to develop a Korean thermality index (KTI) based on the distribution patterns of benthic macroinvertebrates according to altitude and latitude. Analyzing seasonal data (4,853 sampling units) surveyed and collected during 2007 ~ 2011 at 846 sites in South Korea, we estimated thermal valency, thermal value and indicator weight value of 208 species. Among them, 40 species in 6 orders (Decapoda 1 species, Collembola 1 species, Ephemeroptera 5 species, Plecoptera 17 species, Diptera 3 species, Trichoptera 13 species) were selected as the candidate indicator species sensitive and vulnerable to warmth along with climate change. KTI and Benthic macroinvertebrate index (BMI) were tested at three clean streams (Hangye stream, Buk stream and Bangtae stream). KTI showed significant differences according to altitude and water temperature whereas the saprobity index BMI showed little differences. This result means that KTI can be applicable to assess the impact of water temperature independently of organic pollutants.

• Animal Systematics, Evolution and Diversity
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• v.39 no.1
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• pp.47-52
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• 2023

Thermopolynoe Miura, 1994 is a monotypic genus in Lepidonotopodinae that comprises species endemic to chemosynthesis-based ecosystems. Here, we examined T. branchiata collected from the hydrothermal vents in the North Fiji Basin. For the first time in Thermopolynoe, we report sexual dimorphism detecting nephridial papillae on segments 11-13 in males, additionally describe the morphology on elytra with round to conical microtubercles on the surface, and distinguish presence of small neuropodial lobes on segments 3-26. We also revised couple of errors and ambiguities in the original description: incongruence between the description and figure and existence of individual variation in ratio of tentacular cirri and palps. In addition, three COI sequences of T. branchiata specimens from the North Fiji Basin were newly obtained and sequences divergence with other Lepidonotopodinae species were determined. These results would contribute to the taxonomy of polynoids in a chemosynthesis-based ecosystem.